Re: [Biofuel] Glycerine Settling Time
Thanks Joe. Hi Keith; Most often the process comes to 95% or more complete and that is good enough for me ( personal choice) and doesn't give me wash problems either. Maybe 20% of the time it only gets to somewhere around 90% and this is a problem. It tends to be most likely to happen when the feedstock titrates with a result of higher than 5 (this is titrating with KOH soln rather than NaOH) which is what I consider borderline for going acid-base. Settling time is not less than 12 hours for me. Sorry about snipping the remainder of your post, was trying to save bandwidth. Off for the weekend now will check messages on Monday. Hope you are having a good weekend. And also to those about to start the weekend. Tirah Joe Keith Addison wrote: Hi Joe Hi Keith; See my answers below. Keith Addison wrote: Well, settling time is free. Acid-base aside, there's the two-stage base-base process, which quite a lot of people use and like, but otherwise why do more than one stage? Do you mean two separate stages, with a methanol test in between? So you process it twice? Plus extra methanol. No,- more like aiming for a single stage and then using the methanol test right after the settling period (after draining the glycerol of course) it gives you a chance to hit the reactor with another small dose of methoxide if it wasn't quite a complete reaction. The test also tells you how much to use. There is no standardising the process here since the feed is never the same twice. I don't think anybody's feedstock is ever the same twice, unless they're getting it from a food factory with a standardised operation. No restaurant cooks exactly the same food in the same way two days running. Anyway, why should that mean changing anything but the amount of catalyst needed? That's what titration is for, no? Certainly you can standardise the other variables. Rod decided to try a methanol test before washing, just for giggles and it turned out to be a heluva good idea. You know right away if you got a good reaction without having to waste all the time energy and water washing and drying before doing a quality test and then potenially having to reprocess. Before you started using this extra stage, how often did you have to reprocess? In your previous message it sounded like it happened regularly, and it still sounds that way. It turns out this looks just like a two step base -base type deal. but more like 90% of it in one step and then a polishing step. Sometimes if your process was good you don't need to do it, but if it turns out you were not near enough to completion it's nice to know right away. There's still methanol in the esters at that point (before washing) so it's advantageous to push the process further at that point if it is necessary. Joe This seems to raise more questions than provide answers. There were also some other points in my reply to Tom, eg, how long do you let the glycerin settle before draining it and embarking on the second stage/polishing step or whatever? I'll put the rest of my message back, below. Please see my reply to Tom: http://tinyurl.com/3ccqhwhttp://tinyurl.com/3ccqhw [Biofuel] Glycerine Settling Time Best Keith Hi Joe Tom; It makes sense. Glycerin is an emulsifier. Have you ever tried dosing the batch again with a little methoxide? After you remove the glycerin it doesn't take much to get the last bit of the reaction to go and settle out the remaining glycerin. Of course this is well known already. Kenji and many others do straight base catalysis as a two stage deal. You can do a methanol test of sorts and the unreacted oil will settle out. Then you can use the measured amount of unreacted oil in the methanol test vial to estimate the percentage unreacted oil in your batch and dose accordingly with the stoichiometric amount of methoxide. Assume neutral oil for this calculation. Rod and I do this regularly if the batch fails the QT and it works like a charm. Will save you settling time in the long run. Well, settling time is free. Acid-base aside, there's the two-stage base-base process, which quite a lot of people use and like, but otherwise why do more than one stage? Do you mean two separate stages, with a methanol test in between? So you process it twice? Plus extra methanol. Why not do it in a single phase? Todd Swearingen once suggested this here (discussing mixing pump sizes): To judge an appropriate reaction time, pull an exact amount of fluid (200 ml would suffice) out of the reaction stream every half-hour or hour after an arbitrary initial ~1 hour reaction period. Presuming that the contents of the reactor are kept homogenous from the pump flow, the volume of the glycerol cocktail that settles out of each sample will give you a fair gauge as to when your reaction completed. The suggestion would be to continue the reaction for ~1/2 hour beyond the point where your glyc cocktail volume stabilized. That works.
Re: [Biofuel] Glycerine Settling Time
Hello to All, This is an attempt to get things in focus for myself at least. I think this topic started with Re:Biodiesel Quality Test On 8/7/07 Mike W. stated that he allows his batches to settle for a week before washing; No problems with wash. On 8/7/07 I agreed, stated an observation and asked question: I have been wondering about something. When I started making BD it would never pass the methanol quality test. I inevitably got emulsions in the wash. Now, when I make BD for my oil-fired boiler, I use only about 16-17% (vol/vol) of methanol. The BD does not pass the quality test, but I don't have the same emulsion problems. Is it because I let it settle longer (24+ hours vs 6 - 8 hrs)? Does the presence of a small amount of glycerine/soaps make that much of a difference when trying to wash BD from an incomplete reaction? On 8/7/07 Joe Street wrote: Rod believes that glycerin settles slower in a poorly completed reaction. I believe he is right. And yes it only takes a little glycerin to emulsify your wash. Question: If Mono- and Di- Glycerides are such effective emulsifiers, and they don't settle out with the glycerin mix, why don't they emulsify my poor quality (heating system) BD? It seems that something in the glycerine cocktail (that does settle out) is the culpret. Tom ___ Biofuel mailing list Biofuel@sustainablelists.org http://sustainablelists.org/mailman/listinfo/biofuel_sustainablelists.org Biofuel at Journey to Forever: http://journeytoforever.org/biofuel.html Search the combined Biofuel and Biofuels-biz list archives (50,000 messages): http://www.mail-archive.com/biofuel@sustainablelists.org/
Re: [Biofuel] Glycerine Settling Time
Joe, he took washed esters that passed the methanol test and added water and (of course) no emulsion when agitate I used veg oil and water. (No emulsion) Added Glycerin (split) . failed to separate (emulsion?) I'll go back and test BD . will actually do measurements and everything. Tom - Original Message - From: Joe Street To: biofuel@sustainablelists.org Sent: Friday, August 10, 2007 9:45 AM Subject: Re: [Biofuel] Glycerine Settling Time Hi Jan; Ok your post agrees with what Andres said. So how do we explain Tom's experiment then? To recap (Tom correct me if I miss something here) he took washed esters that passed the methanol test and added water and (of course) no emulsion when agitated. Whatever mono and diglycerides were in the esters were small but present I assume, but yet no emusion. Then added some small quantity of glycerol ( which had been separated from the soaps, FFA and salts) and agitated again and did get an emulsion. I have had the feeling glycerin has usually been the cause of emulsion problems when I have had them. No doubt a poorly reacted batch is much more likely to have the problem but is that really due to the glycerides or is it glycerin which hasn't settled. Remember we started this discussion that the glycerin settles much slower in a poorly completed run. BTW as an addition to this discussion look what someone just posted on my yahoo group! Using glycerin cocktail to BREAK an emulsion. Now that's radical!!?? http://www.biodieselcommunity.org/breakingemulsions/ Joe Jan Warnqvist wrote: Hi evereybody. I feel obliged to enter this discussion. Pure glycerine is not a good emulsifier due to the fact that there are three OH-groups and that the carbon s in the first and third positions are surronded by two hydrogene atoms. This makes the glycerine hydrophilic in five places alltogether. However, the mono- and diglycerides are excellent emulsifiers. Only small amounts of these are sufficient to create stable emulsions. Would somebody agree with me on that ? Jan Warnqvist - Original Message - From: Keith Addison [EMAIL PROTECTED] To: biofuel@sustainablelists.org Sent: Friday, August 10, 2007 9:53 AM Subject: Re: [Biofuel] Glycerine Settling Time Hi Tom Hi Keith, Then if you do one-litre test batches first, especially with iffy batches of oil, Ops. I took Joe's point to be: If you have to re-process it is possible to use info from the QT to determine how much (how little) methanol you'll need to use. I also took that point, there were others though. It's a useful method, cheaper reprocessing, but I think we all agree that reprocessing itself is to be avoided if at all possible. Or I thought we did anyway. I think that both Joe and myself have standardize(d) the process so that passing the QT is the rule, not the exception. That's not what Joe said: It makes sense. Glycerin is an emulsifier. Have you ever tried dosing the batch again with a little methoxide? After you remove the glycerin it doesn't take much to get the last bit of the reaction to go and settle out the remaining glycerin. Of course this is well known already. Kenji and many others do straight base catalysis as a two stage deal. You can do a methanol test of sorts and the unreacted oil will settle out. Then you can use the measured amount of unreacted oil in the methanol test vial to estimate the percentage unreacted oil in your batch and dose accordingly with the stoichiometric amount of methoxide. Assume neutral oil for this calculation. Rod and I do this regularly if the batch fails the QT and it works like a charm. Will save you settling time in the long run. Rod and I do this regularly if the batch fails the QT and it works like a charm. That if makes it a little ambiguous, but the regularly bit puts a question-mark on what's the rule and what's the exception. Kenji and many others do straight base catalysis as a two stage deal. Less methanol notwithstanding, my question remains - why reprocess, as a standard procedure, instead of avoiding the problem in the first place? Could be wrong, but it sounds like Kenji and others might be doing this rather than doing a titration - you know the old line: There's no need for titration, just use 6.25 g. And then using the methanol test to try to fix the regularly ensuing disaster. A different version of that here in Japan is to put the stuff through a centrifuge, though the product still doesn't pass any quality test or standards test. What you describe is much the same as what I described, doing (whatever) tests during the processing, adjusting accordingly and conducting the whole thing as a single stage. From Joe's replies so far I can't tell if he (and Rod, and Kenji and many others) are doing it that way or not, but it seems not: Your
Re: [Biofuel] Glycerine Settling Time
Jan Warnqvist wrote: Hello Joe. There were probably small amounts of mono- and diglycerides left in the biodiesel, and/or possibly soaps which together are excellent emulsifiers. So then one would expect that the water added and shaken would emulsify due to those mono and di-glycerides, but it didn't happen. What's up with that? A strong acid will divide the glycerides into fatty acids and glycerine ,and the soaps into salts and fatty acids, which then goes into a fat phanse and an aquaeus phase, possibly with the salts in the bottom.' Best regards Jan - Original Message - *From:* Joe Street mailto:[EMAIL PROTECTED] *To:* biofuel@sustainablelists.org mailto:biofuel@sustainablelists.org *Sent:* Friday, August 10, 2007 3:45 PM *Subject:* Re: [Biofuel] Glycerine Settling Time Hi Jan; Ok your post agrees with what Andres said. So how do we explain Tom's experiment then? To recap (Tom correct me if I miss something here) he took washed esters that passed the methanol test and added water and (of course) no emulsion when agitated. Whatever mono and diglycerides were in the esters were small but present I assume, but yet no emusion. Then added some small quantity of glycerol ( which had been separated from the soaps, FFA and salts) and agitated again and did get an emulsion. I have had the feeling glycerin has usually been the cause of emulsion problems when I have had them. No doubt a poorly reacted batch is much more likely to have the problem but is that really due to the glycerides or is it glycerin which hasn't settled. Remember we started this discussion that the glycerin settles much slower in a poorly completed run. BTW as an addition to this discussion look what someone just posted on my yahoo group! Using glycerin cocktail to BREAK an emulsion. Now that's radical!!?? http://www.biodieselcommunity.org/breakingemulsions/ Joe Jan Warnqvist wrote: Hi evereybody. I feel obliged to enter this discussion. Pure glycerine is not a good emulsifier due to the fact that there are three OH-groups and that the carbon s in the first and third positions are surronded by two hydrogene atoms. This makes the glycerine hydrophilic in five places alltogether. However, the mono- and diglycerides are excellent emulsifiers. Only small amounts of these are sufficient to create stable emulsions. Would somebody agree with me on that ? Jan Warnqvist - Original Message - From: Keith Addison [EMAIL PROTECTED] To: biofuel@sustainablelists.org Sent: Friday, August 10, 2007 9:53 AM Subject: Re: [Biofuel] Glycerine Settling Time Hi Tom Hi Keith, Then if you do one-litre test batches first, especially with iffy batches of oil, Ops. I took Joe's point to be: If you have to re-process it is possible to use info from the QT to determine how much (how little) methanol you'll need to use. I also took that point, there were others though. It's a useful method, cheaper reprocessing, but I think we all agree that reprocessing itself is to be avoided if at all possible. Or I thought we did anyway. I think that both Joe and myself have standardize(d) the process so that passing the QT is the rule, not the exception. That's not what Joe said: It makes sense. Glycerin is an emulsifier. Have you ever tried dosing the batch again with a little methoxide? After you remove the glycerin it doesn't take much to get the last bit of the reaction to go and settle out the remaining glycerin. Of course this is well known already. Kenji and many others do straight base catalysis as a two stage deal. You can do a methanol test of sorts and the unreacted oil will settle out. Then you can use the measured amount of unreacted oil in the methanol test vial to estimate the percentage unreacted oil in your batch and dose accordingly with the stoichiometric amount of methoxide. Assume neutral oil for this calculation. Rod and I do this regularly if the batch fails the QT and it works like a charm. Will save you settling time in the long run. Rod and I do this regularly if the batch fails the QT and it works like a charm. That if makes it a little ambiguous, but the regularly bit puts a question-mark on what's the rule and what's the exception. Kenji and many others do straight base catalysis as a two stage deal. Less methanol notwithstanding, my question remains - why reprocess, as a standard procedure, instead of avoiding the problem in the first place? Could be wrong, but it sounds like Kenji and others might be doing this rather than doing a titration - you know the old line: There's no need for titration, just use 6.25 g. And then using the methanol test to try to fix the regularly ensuing disaster. A different version of that here in Japan is to put the stuff through a centrifuge, though the product
Re: [Biofuel] Glycerine Settling Time
Keith, You wrote: I think this is a misunderstanding. I didn't say what you say below, standardized; can't fail, and I didn't mean that standardising the process means there's no need for tests, I apologize for a poor choice of wording suggesting a misunderstanding. You are unquestionably a proponent of quality testing. -Tweak the process to get consistently good BD. -How do you know you have succeeded in tweaking just right? QT -QT each batch Who did I learn this from? Re: Big lunch You and Robert inspired me last summer to grow more edibles. I had moved towards flowers. Now I grow more of what I eat, and I'm eating pretty good. A short while back there was discussion of growing fruits/veggies on lawns, side yards, etc. I mention what I had for lunch or dinner just to keep the thought alive. You can grow good food even on a little patch of land. The experience is priceless. poached Muscovy egg and stir-fried Swiss chard in the offing... M Mm Mm I'm getting hungry Tom - Original Message - From: Keith Addison [EMAIL PROTECTED] To: biofuel@sustainablelists.org Sent: Friday, August 10, 2007 3:53 AM Subject: Re: [Biofuel] Glycerine Settling Time Hi Tom Hi Keith, Then if you do one-litre test batches first, especially with iffy batches of oil, Ops. I took Joe's point to be: If you have to re-process it is possible to use info from the QT to determine how much (how little) methanol you'll need to use. I also took that point, there were others though. It's a useful method, cheaper reprocessing, but I think we all agree that reprocessing itself is to be avoided if at all possible. Or I thought we did anyway. I think that both Joe and myself have standardize(d) the process so that passing the QT is the rule, not the exception. That's not what Joe said: It makes sense. Glycerin is an emulsifier. Have you ever tried dosing the batch again with a little methoxide? After you remove the glycerin it doesn't take much to get the last bit of the reaction to go and settle out the remaining glycerin. Of course this is well known already. Kenji and many others do straight base catalysis as a two stage deal. You can do a methanol test of sorts and the unreacted oil will settle out. Then you can use the measured amount of unreacted oil in the methanol test vial to estimate the percentage unreacted oil in your batch and dose accordingly with the stoichiometric amount of methoxide. Assume neutral oil for this calculation. Rod and I do this regularly if the batch fails the QT and it works like a charm. Will save you settling time in the long run. Rod and I do this regularly if the batch fails the QT and it works like a charm. That if makes it a little ambiguous, but the regularly bit puts a question-mark on what's the rule and what's the exception. Kenji and many others do straight base catalysis as a two stage deal. Less methanol notwithstanding, my question remains - why reprocess, as a standard procedure, instead of avoiding the problem in the first place? Could be wrong, but it sounds like Kenji and others might be doing this rather than doing a titration - you know the old line: There's no need for titration, just use 6.25 g. And then using the methanol test to try to fix the regularly ensuing disaster. A different version of that here in Japan is to put the stuff through a centrifuge, though the product still doesn't pass any quality test or standards test. What you describe is much the same as what I described, doing (whatever) tests during the processing, adjusting accordingly and conducting the whole thing as a single stage. From Joe's replies so far I can't tell if he (and Rod, and Kenji and many others) are doing it that way or not, but it seems not: Your question (and mine): Don't you have to heat up the whole batch again? (Time and energy) Joe's reply: This is all done right after draining the glycerin. I leave the heater on during this period. Do the rough QT right away before wash test. Rough QT? Anyway, how long is it settling before he drains the glyc? I run a QT towards the end of the reaction because I do not want to re-process. Indeed not. It takes me a few minutes and I like the certainty of knowing the BD is good before I pump it into my settling tank. If the test should fail when I'm making a batch for my car, I could use Joe's suggestion to help me better approximate the amount of methanol to add. If the process has been standardized, why bother? I think this is a misunderstanding. I didn't say what you say below, standardized; can't fail, and I didn't mean that standardising the process means there's no need for tests, whether in-process tests or 1-litre test batches or whatever. Anything can
Re: [Biofuel] Glycerine Settling Time
Hi Joe Hi Keith; See my answers below. Keith Addison wrote: Well, settling time is free. Acid-base aside, there's the two-stage base-base process, which quite a lot of people use and like, but otherwise why do more than one stage? Do you mean two separate stages, with a methanol test in between? So you process it twice? Plus extra methanol. No,- more like aiming for a single stage and then using the methanol test right after the settling period (after draining the glycerol of course) it gives you a chance to hit the reactor with another small dose of methoxide if it wasn't quite a complete reaction. The test also tells you how much to use. There is no standardising the process here since the feed is never the same twice. I don't think anybody's feedstock is ever the same twice, unless they're getting it from a food factory with a standardised operation. No restaurant cooks exactly the same food in the same way two days running. Anyway, why should that mean changing anything but the amount of catalyst needed? That's what titration is for, no? Certainly you can standardise the other variables. Rod decided to try a methanol test before washing, just for giggles and it turned out to be a heluva good idea. You know right away if you got a good reaction without having to waste all the time energy and water washing and drying before doing a quality test and then potenially having to reprocess. Before you started using this extra stage, how often did you have to reprocess? In your previous message it sounded like it happened regularly, and it still sounds that way. It turns out this looks just like a two step base -base type deal. but more like 90% of it in one step and then a polishing step. Sometimes if your process was good you don't need to do it, but if it turns out you were not near enough to completion it's nice to know right away. There's still methanol in the esters at that point (before washing) so it's advantageous to push the process further at that point if it is necessary. Joe This seems to raise more questions than provide answers. There were also some other points in my reply to Tom, eg, how long do you let the glycerin settle before draining it and embarking on the second stage/polishing step or whatever? I'll put the rest of my message back, below. Please see my reply to Tom: http://tinyurl.com/3ccqhw [Biofuel] Glycerine Settling Time Best Keith Hi Joe Tom; It makes sense. Glycerin is an emulsifier. Have you ever tried dosing the batch again with a little methoxide? After you remove the glycerin it doesn't take much to get the last bit of the reaction to go and settle out the remaining glycerin. Of course this is well known already. Kenji and many others do straight base catalysis as a two stage deal. You can do a methanol test of sorts and the unreacted oil will settle out. Then you can use the measured amount of unreacted oil in the methanol test vial to estimate the percentage unreacted oil in your batch and dose accordingly with the stoichiometric amount of methoxide. Assume neutral oil for this calculation. Rod and I do this regularly if the batch fails the QT and it works like a charm. Will save you settling time in the long run. Well, settling time is free. Acid-base aside, there's the two-stage base-base process, which quite a lot of people use and like, but otherwise why do more than one stage? Do you mean two separate stages, with a methanol test in between? So you process it twice? Plus extra methanol. Why not do it in a single phase? Todd Swearingen once suggested this here (discussing mixing pump sizes): To judge an appropriate reaction time, pull an exact amount of fluid (200 ml would suffice) out of the reaction stream every half-hour or hour after an arbitrary initial ~1 hour reaction period. Presuming that the contents of the reactor are kept homogenous from the pump flow, the volume of the glycerol cocktail that settles out of each sample will give you a fair gauge as to when your reaction completed. The suggestion would be to continue the reaction for ~1/2 hour beyond the point where your glyc cocktail volume stabilized. That works. Then, surely, you can standardise the process, with the only variable the amount of lye according to the titration level. Then if you do one-litre test batches first, especially with iffy batches of oil, and you have a clear idea of how your test-batch processing relates to your full-scale processing, life should be easier and there shouldn't be any batches failing the QT. What did I miss? ___ Biofuel mailing list Biofuel@sustainablelists.org http://sustainablelists.org/mailman/listinfo/biofuel_sustainablelists.org Biofuel at Journey to Forever: http://journeytoforever.org/biofuel.html Search the combined Biofuel and Biofuels-biz list archives (50,000 messages):
Re: [Biofuel] Glycerine Settling Time
it comes to broad horizons. But quite often it's quicker just to amble on out and eat a bit of garden in the meantime, and pin one's hopes on a big dinner. On the other hand, I think there just might be some poached Muscovy egg and stir-fried Swiss chard in the offing... Man, it's going to be hard ever to go back to the city life. All best Keith Tom - Original Message - From: Keith Addison [EMAIL PROTECTED] To: biofuel@sustainablelists.org Sent: Thursday, August 09, 2007 3:36 PM Subject: Re: [Biofuel] Glycerine Settling Time Hi Joe Tom; It makes sense. Glycerin is an emulsifier. Have you ever tried dosing the batch again with a little methoxide? After you remove the glycerin it doesn't take much to get the last bit of the reaction to go and settle out the remaining glycerin. Of course this is well known already. Kenji and many others do straight base catalysis as a two stage deal. You can do a methanol test of sorts and the unreacted oil will settle out. Then you can use the measured amount of unreacted oil in the methanol test vial to estimate the percentage unreacted oil in your batch and dose accordingly with the stoichiometric amount of methoxide. Assume neutral oil for this calculation. Rod and I do this regularly if the batch fails the QT and it works like a charm. Will save you settling time in the long run. Well, settling time is free. Acid-base aside, there's the two-stage base-base process, which quite a lot of people use and like, but otherwise why do more than one stage? Do you mean two separate stages, with a methanol test in between? So you process it twice? Plus extra methanol. Why not do it in a single phase? Todd Swearingen once suggested this here (discussing mixing pump sizes): To judge an appropriate reaction time, pull an exact amount of fluid (200 ml would suffice) out of the reaction stream every half-hour or hour after an arbitrary initial ~1 hour reaction period. Presuming that the contents of the reactor are kept homogenous from the pump flow, the volume of the glycerol cocktail that settles out of each sample will give you a fair gauge as to when your reaction completed. The suggestion would be to continue the reaction for ~1/2 hour beyond the point where your glyc cocktail volume stabilized. That works. Then, surely, you can standardise the process, with the only variable the amount of lye according to the titration level. Then if you do one-litre test batches first, especially with iffy batches of oil, and you have a clear idea of how your test-batch processing relates to your full-scale processing, life should be easier and there shouldn't be any batches failing the QT. What did I miss? Big skies :-) And broad horizons. Keith Joe Thomas Kelly wrote: Joe, I took a sample from my latest batch of BD destined for my boiler (failed QT; but very little residue dropped out). It had settled for almost 10 hrs. That was yesterday morning. Today there is a small, but noticable, bit of glycerine on the bottom. More settled out after the initial 10 hrs of settling. I don't have any results with good BD to compare it with. If it turns out that glycerine settles out slower from incomplete vs complete reactions, it would answer the question I asked about getting emulsions when I washed low quality BD after letting it settle overnight, but not getting emulsions when it settled for a few days to a week. It would also help with a friendly disagreement I have with a friend. He seems to think that unreacted glycerides will settle out of the BD given time. He has taken to going with about 16% (vol/vol) of methanol in his batches. His logic: Unreacted oil causes emulsions, right? The emulsions I get in the first wash after settling the BD overnight are due to the unreacted oil? When I let it settle for a week or more I don't get emulsions, therefore the unreacted oil must have settled out. More likely: Some unreacted glycerides are still there, but after a week of settling more of the glycerine has settled out. Even a small amount of glycerine compound the emulsifying effects of the unreacted glycerides . Yes? By the way, I always ask him Did you do a quality test? His answer: Oops, I forgot. Thanks Joe and Rod . for bringing this to my attention A push to make a lot of BD for heat is just around the corner. It might be best to include more settling time in the schedule. Tom - Original Message - From: mailto:[EMAIL PROTECTED]Joe Street To: mailto:biofuel@sustainablelists.orgbiofuel@sustainablelists.org Sent: Tuesday, August 07, 2007 3:02 PM Subject: Re: [Biofuel] Biofuel Quality Test Hey Tom; Take a sample from your fuel after settling 6-8
Re: [Biofuel] Glycerine Settling Time
Hi Tom Keith, You wrote: I think this is a misunderstanding. I didn't say what you say below, standardized; can't fail, and I didn't mean that standardising the process means there's no need for tests, I apologize for a poor choice of wording suggesting a misunderstanding. Thankyou Tom, but mea culpa, I could have been clearer about it but it was late and I was whacked. You are unquestionably a proponent of quality testing. -Tweak the process to get consistently good BD. -How do you know you have succeeded in tweaking just right? QT -QT each batch Who did I learn this from? :-) Who did I learn it from? Partly from some really bad examples that I think you're aware of, but mostly from the collective wisdom of the Biofuel list. To which you contribute a great deal. I guess we all owe each other eh? Re: Big lunch You and Robert inspired me last summer to grow more edibles. Then Robert and I will go to heaven! (And so will you!) I had moved towards flowers. Now I grow more of what I eat, and I'm eating pretty good. A short while back there was discussion of growing fruits/veggies on lawns, side yards, etc. I mention what I had for lunch or dinner just to keep the thought alive. You can grow good food even on a little patch of land. The experience is priceless. Indeed it is. Thankyou for keeping the thought alive, please don't stop. poached Muscovy egg and stir-fried Swiss chard in the offing... M Mm Mm I'm getting hungry :-) I'm getting sleepy! Later... Best Keith Tom - Original Message - From: Keith Addison [EMAIL PROTECTED] To: biofuel@sustainablelists.org Sent: Friday, August 10, 2007 3:53 AM Subject: Re: [Biofuel] Glycerine Settling Time Hi Tom Hi Keith, Then if you do one-litre test batches first, especially with iffy batches of oil, Ops. I took Joe's point to be: If you have to re-process it is possible to use info from the QT to determine how much (how little) methanol you'll need to use. I also took that point, there were others though. It's a useful method, cheaper reprocessing, but I think we all agree that reprocessing itself is to be avoided if at all possible. Or I thought we did anyway. I think that both Joe and myself have standardize(d) the process so that passing the QT is the rule, not the exception. That's not what Joe said: It makes sense. Glycerin is an emulsifier. Have you ever tried dosing the batch again with a little methoxide? After you remove the glycerin it doesn't take much to get the last bit of the reaction to go and settle out the remaining glycerin. Of course this is well known already. Kenji and many others do straight base catalysis as a two stage deal. You can do a methanol test of sorts and the unreacted oil will settle out. Then you can use the measured amount of unreacted oil in the methanol test vial to estimate the percentage unreacted oil in your batch and dose accordingly with the stoichiometric amount of methoxide. Assume neutral oil for this calculation. Rod and I do this regularly if the batch fails the QT and it works like a charm. Will save you settling time in the long run. Rod and I do this regularly if the batch fails the QT and it works like a charm. That if makes it a little ambiguous, but the regularly bit puts a question-mark on what's the rule and what's the exception. Kenji and many others do straight base catalysis as a two stage deal. Less methanol notwithstanding, my question remains - why reprocess, as a standard procedure, instead of avoiding the problem in the first place? Could be wrong, but it sounds like Kenji and others might be doing this rather than doing a titration - you know the old line: There's no need for titration, just use 6.25 g. And then using the methanol test to try to fix the regularly ensuing disaster. A different version of that here in Japan is to put the stuff through a centrifuge, though the product still doesn't pass any quality test or standards test. What you describe is much the same as what I described, doing (whatever) tests during the processing, adjusting accordingly and conducting the whole thing as a single stage. From Joe's replies so far I can't tell if he (and Rod, and Kenji and many others) are doing it that way or not, but it seems not: Your question (and mine): Don't you have to heat up the whole batch again? (Time and energy) Joe's reply: This is all done right after draining the glycerin. I leave the heater on during this period. Do the rough QT right away before wash test. Rough QT? Anyway, how long is it settling before he drains the glyc? I run a QT towards the end of the reaction because I do not want to re-process
Re: [Biofuel] Glycerine Settling Time
Hi evereybody. I feel obliged to enter this discussion. Pure glycerine is not a good emulsifier due to the fact that there are three OH-groups and that the carbon s in the first and third positions are surronded by two hydrogene atoms. This makes the glycerine hydrophilic in five places alltogether. However, the mono- and diglycerides are excellent emulsifiers. Only small amounts of these are sufficient to create stable emulsions. Would somebody agree with me on that ? Jan Warnqvist - Original Message - From: Keith Addison [EMAIL PROTECTED] To: biofuel@sustainablelists.org Sent: Friday, August 10, 2007 9:53 AM Subject: Re: [Biofuel] Glycerine Settling Time Hi Tom Hi Keith, Then if you do one-litre test batches first, especially with iffy batches of oil, Ops. I took Joe's point to be: If you have to re-process it is possible to use info from the QT to determine how much (how little) methanol you'll need to use. I also took that point, there were others though. It's a useful method, cheaper reprocessing, but I think we all agree that reprocessing itself is to be avoided if at all possible. Or I thought we did anyway. I think that both Joe and myself have standardize(d) the process so that passing the QT is the rule, not the exception. That's not what Joe said: It makes sense. Glycerin is an emulsifier. Have you ever tried dosing the batch again with a little methoxide? After you remove the glycerin it doesn't take much to get the last bit of the reaction to go and settle out the remaining glycerin. Of course this is well known already. Kenji and many others do straight base catalysis as a two stage deal. You can do a methanol test of sorts and the unreacted oil will settle out. Then you can use the measured amount of unreacted oil in the methanol test vial to estimate the percentage unreacted oil in your batch and dose accordingly with the stoichiometric amount of methoxide. Assume neutral oil for this calculation. Rod and I do this regularly if the batch fails the QT and it works like a charm. Will save you settling time in the long run. Rod and I do this regularly if the batch fails the QT and it works like a charm. That if makes it a little ambiguous, but the regularly bit puts a question-mark on what's the rule and what's the exception. Kenji and many others do straight base catalysis as a two stage deal. Less methanol notwithstanding, my question remains - why reprocess, as a standard procedure, instead of avoiding the problem in the first place? Could be wrong, but it sounds like Kenji and others might be doing this rather than doing a titration - you know the old line: There's no need for titration, just use 6.25 g. And then using the methanol test to try to fix the regularly ensuing disaster. A different version of that here in Japan is to put the stuff through a centrifuge, though the product still doesn't pass any quality test or standards test. What you describe is much the same as what I described, doing (whatever) tests during the processing, adjusting accordingly and conducting the whole thing as a single stage. From Joe's replies so far I can't tell if he (and Rod, and Kenji and many others) are doing it that way or not, but it seems not: Your question (and mine): Don't you have to heat up the whole batch again? (Time and energy) Joe's reply: This is all done right after draining the glycerin. I leave the heater on during this period. Do the rough QT right away before wash test. Rough QT? Anyway, how long is it settling before he drains the glyc? I run a QT towards the end of the reaction because I do not want to re-process. Indeed not. It takes me a few minutes and I like the certainty of knowing the BD is good before I pump it into my settling tank. If the test should fail when I'm making a batch for my car, I could use Joe's suggestion to help me better approximate the amount of methanol to add. If the process has been standardized, why bother? I think this is a misunderstanding. I didn't say what you say below, standardized; can't fail, and I didn't mean that standardising the process means there's no need for tests, whether in-process tests or 1-litre test batches or whatever. Anything can fail. I'm all in favour of any tests that are helpful at any stage. So I agree with all you say here. Indeed, whatever rough might mean, using the methanol test to fine-tune the amount of extra methanol needed for reprocessing is a useful technique. But I'm not in favour of using reprocessing as a standard method, which, pending a better explanation, seems to be what's being proposed here. As you say: there shouldn't be any batches failing the QT. I've had a few failed batches in the past year. It seems to happen when I think I have it all figured out; standardized; can't fail. On one occasion the pump was making a bit of a funny noise when I
Re: [Biofuel] Glycerine Settling Time
Andres, Emulsifiers contains a clear lipofilic and hidrofilic zones in the molecule. In mono- and di- glycerides the glycerin supplies the hydrophilic zone and the fatty acid chain(s) supply the hydrophobic (lipophilic) zones. The -OH groups in the glycerin give it regions of charge making it hydrophilic. In an aquous solution wouldn't these groups rotate towards the water exposing hydrocarbons (hydrophobic) to the BD? I just tried forming an emulsion with veg oil and tap water. The oil rose to the top. I added glycerine that was split from the glycerine cocktail using Phosphoric Acid. It has no soaps, FFA's, methanol or KOH. I shook the bottle and the oil and water did not separate . an emulsion? I then added some vinegar. The emulsion broke. Glycerine seems to be an emulsifier. Am I missing something? Tom Maybe it's worth trying it again and seeing how long it stays emulsified. Best Keith - Original Message - From: mailto:[EMAIL PROTECTED]Andres Secco To: mailto:biofuel@sustainablelists.orgbiofuel@sustainablelists.org Sent: Thursday, August 09, 2007 1:55 PM Subject: Re: [Biofuel] Glycerine Settling Time Joe, For the sake of precise concepts, gliceryn is NOT an emulsifier. Emulsifiers contains a clear lipofilic and hidrofilic zones in the molecule. Which is an emulsifier is the partially reacted mono or di-glicerides, but in a crystal clear liquid there are not emulsions or dispersions. Glycerin is dissolved in the BD and separates from the liquid BD phase with time. - Original Message - From: mailto:[EMAIL PROTECTED]Joe Street To: mailto:biofuel@sustainablelists.orgbiofuel@sustainablelists.org Sent: Thursday, August 09, 2007 11:30 AM Subject: Re: [Biofuel] Glycerine Settling Time Tom; It makes sense. Glycerin is an emulsifier. Have you ever tried dosing the batch again with a little methoxide? After you remove the glycerin it doesn't take much to get the last bit of the reaction to go and settle out the remaining glycerin. Of course this is well known already. Kenji and many others do straight base catalysis as a two stage deal. You can do a methanol test of sorts and the unreacted oil will settle out. Then you can use the measured amount of unreacted oil in the methanol test vial to estimate the percentage unreacted oil in your batch and dose accordingly with the stoichiometric amount of methoxide. Assume neutral oil for this calculation. Rod and I do this regularly if the batch fails the QT and it works like a charm. Will save you settling time in the long run. Big skies Joe Thomas Kelly wrote: Joe, I took a sample from my latest batch of BD destined for my boiler (failed QT; but very little residue dropped out). It had settled for almost 10 hrs. That was yesterday morning. Today there is a small, but noticable, bit of glycerine on the bottom. More settled out after the initial 10 hrs of settling. I don't have any results with good BD to compare it with. If it turns out that glycerine settles out slower from incomplete vs complete reactions, it would answer the question I asked about getting emulsions when I washed low quality BD after letting it settle overnight, but not getting emulsions when it settled for a few days to a week. It would also help with a friendly disagreement I have with a friend. He seems to think that unreacted glycerides will settle out of the BD given time. He has taken to going with about 16% (vol/vol) of methanol in his batches. His logic: Unreacted oil causes emulsions, right? The emulsions I get in the first wash after settling the BD overnight are due to the unreacted oil? When I let it settle for a week or more I don't get emulsions, therefore the unreacted oil must have settled out. More likely: Some unreacted glycerides are still there, but after a week of settling more of the glycerine has settled out. Even a small amount of glycerine compound the emulsifying effects of the unreacted glycerides . Yes? By the way, I always ask him Did you do a quality test? His answer: Oops, I forgot. Thanks Joe and Rod . for bringing this to my attention A push to make a lot of BD for heat is just around the corner. It might be best to include more settling time in the schedule. Tom - Original Message - From: mailto:[EMAIL PROTECTED]Joe Street To: mailto:biofuel@sustainablelists.orgbiofuel@sustainablelists.org Sent: Tuesday, August 07, 2007 3:02 PM Subject: Re: [Biofuel] Biofuel Quality Test Hey Tom; Take a sample from your fuel after settling 6-8 hrs and set it asside in a mason jar for the longer period and see what settles out. Rod believes that glycerin settles slower in a poorly completed reaction. I believe he is right. And yes it only takes a little glycerin to emulsify your wash
Re: [Biofuel] Glycerine Settling Time
Hi Keith; Most often the process comes to 95% or more complete and that is good enough for me ( personal choice) and doesn't give me wash problems either. Maybe 20% of the time it only gets to somewhere around 90% and this is a problem. It tends to be most likely to happen when the feedstock titrates with a result of higher than 5 (this is titrating with KOH soln rather than NaOH) which is what I consider borderline for going acid-base. Settling time is not less than 12 hours for me. Sorry about snipping the remainder of your post, was trying to save bandwidth. Off for the weekend now will check messages on Monday. Hope you are having a good weekend. And also to those about to start the weekend. Tirah Joe Keith Addison wrote: Hi Joe Hi Keith; See my answers below. Keith Addison wrote: Well, settling time is free. Acid-base aside, there's the two-stage base-base process, which quite a lot of people use and like, but otherwise why do more than one stage? Do you mean two separate stages, with a methanol test in between? So you process it twice? Plus extra methanol. No,- more like aiming for a single stage and then using the methanol test right after the settling period (after draining the glycerol of course) it gives you a chance to hit the reactor with another small dose of methoxide if it wasn't quite a complete reaction. The test also tells you how much to use. There is no standardising the process here since the feed is never the same twice. I don't think anybody's feedstock is ever the same twice, unless they're getting it from a food factory with a standardised operation. No restaurant cooks exactly the same food in the same way two days running. Anyway, why should that mean changing anything but the amount of catalyst needed? That's what titration is for, no? Certainly you can standardise the other variables. Rod decided to try a methanol test before washing, just for giggles and it turned out to be a heluva good idea. You know right away if you got a good reaction without having to waste all the time energy and water washing and drying before doing a quality test and then potenially having to reprocess. Before you started using this extra stage, how often did you have to reprocess? In your previous message it sounded like it happened regularly, and it still sounds that way. It turns out this looks just like a two step base -base type deal. but more like 90% of it in one step and then a polishing step. Sometimes if your process was good you don't need to do it, but if it turns out you were not near enough to completion it's nice to know right away. There's still methanol in the esters at that point (before washing) so it's advantageous to push the process further at that point if it is necessary. Joe This seems to raise more questions than provide answers. There were also some other points in my reply to Tom, eg, how long do you let the glycerin settle before draining it and embarking on the second stage/polishing step or whatever? I'll put the rest of my message back, below. Please see my reply to Tom: http://tinyurl.com/3ccqhw [Biofuel] Glycerine Settling Time Best Keith Hi Joe Tom; It makes sense. Glycerin is an emulsifier. Have you ever tried dosing the batch again with a little methoxide? After you remove the glycerin it doesn't take much to get the last bit of the reaction to go and settle out the remaining glycerin. Of course this is well known already. Kenji and many others do straight base catalysis as a two stage deal. You can do a methanol test of sorts and the unreacted oil will settle out. Then you can use the measured amount of unreacted oil in the methanol test vial to estimate the percentage unreacted oil in your batch and dose accordingly with the stoichiometric amount of methoxide. Assume neutral oil for this calculation. Rod and I do this regularly if the batch fails the QT and it works like a charm. Will save you settling time in the long run. Well, settling time is free. Acid-base aside, there's the two-stage base-base process, which quite a lot of people use and like, but otherwise why do more than one stage? Do you mean two separate stages, with a methanol test in between? So you process it twice? Plus extra methanol. Why not do it in a single phase? Todd Swearingen once suggested this here (discussing mixing pump sizes): To judge an appropriate reaction time, pull an exact amount of fluid (200 ml would suffice) out of the reaction stream every half-hour or hour after an arbitrary initial ~1 hour reaction period. Presuming that the contents of the reactor are kept homogenous from the pump flow, the volume of the glycerol cocktail that settles out of each sample will give you a fair gauge as to when your reaction completed. The suggestion would be to continue the reaction for ~1/2 hour beyond the point where your glyc cocktail
Re: [Biofuel] Glycerine Settling Time
Hi Keith; See my answers below. Keith Addison wrote: Well, settling time is free. Acid-base aside, there's the two-stage base-base process, which quite a lot of people use and like, but otherwise why do more than one stage? Do you mean two separate stages, with a methanol test in between? So you process it twice? Plus extra methanol. No,- more like aiming for a single stage and then using the methanol test right after the settling period (after draining the glycerol of course) it gives you a chance to hit the reactor with another small dose of methoxide if it wasn't quite a complete reaction. The test also tells you how much to use. There is no standardising the process here since the feed is never the same twice. Rod decided to try a methanol test before washing, just for giggles and it turned out to be a heluva good idea. You know right away if you got a good reaction without having to waste all the time energy and water washing and drying before doing a quality test and then potenially having to reprocess. It turns out this looks just like a two step base -base type deal. but more like 90% of it in one step and then a polishing step. Sometimes if your process was good you don't need to do it, but if it turns out you were not near enough to completion it's nice to know right away. There's still methanol in the esters at that point (before washing) so it's advantageous to push the process further at that point if it is necessary. Joe ___ Biofuel mailing list Biofuel@sustainablelists.org http://sustainablelists.org/mailman/listinfo/biofuel_sustainablelists.org Biofuel at Journey to Forever: http://journeytoforever.org/biofuel.html Search the combined Biofuel and Biofuels-biz list archives (50,000 messages): http://www.mail-archive.com/biofuel@sustainablelists.org/
Re: [Biofuel] Glycerine Settling Time
Hi all, I just saw the tom experiment results. Think the small quantity of glycerol increased the viscosity and that helps to stabilize the suspension. But I don think this is stable for a long time or if it were an stable emulsion. More likely a suspension wichis like an emulsion but not stable for long time. I did it with water and oil and some happened but nothing to say I have an emulsion here. After a few hours got separated. I agree with Jan that a poorly completed reaction releases mono and di-glicerydes wich have a strong emulsifier capacity and can trap any polar substances in the BD phase, not only glycerine but also proteins and methanol. When I saw the firs time the BD production with a friend in israel he added salt to break any emulsion trace. He left the batch for several days. Now I left for two complete days and all passes the QT test. - Original Message - From: Joe Street To: biofuel@sustainablelists.org Sent: Friday, August 10, 2007 9:45 AM Subject: Re: [Biofuel] Glycerine Settling Time Hi Jan; Ok your post agrees with what Andres said. So how do we explain Tom's experiment then? To recap (Tom correct me if I miss something here) he took washed esters that passed the methanol test and added water and (of course) no emulsion when agitated. Whatever mono and diglycerides were in the esters were small but present I assume, but yet no emusion. Then added some small quantity of glycerol ( which had been separated from the soaps, FFA and salts) and agitated again and did get an emulsion. I have had the feeling glycerin has usually been the cause of emulsion problems when I have had them. No doubt a poorly reacted batch is much more likely to have the problem but is that really due to the glycerides or is it glycerin which hasn't settled. Remember we started this discussion that the glycerin settles much slower in a poorly completed run. BTW as an addition to this discussion look what someone just posted on my yahoo group! Using glycerin cocktail to BREAK an emulsion. Now that's radical!!?? http://www.biodieselcommunity.org/breakingemulsions/ Joe Jan Warnqvist wrote: Hi evereybody. I feel obliged to enter this discussion. Pure glycerine is not a good emulsifier due to the fact that there are three OH-groups and that the carbon s in the first and third positions are surronded by two hydrogene atoms. This makes the glycerine hydrophilic in five places alltogether. However, the mono- and diglycerides are excellent emulsifiers. Only small amounts of these are sufficient to create stable emulsions. Would somebody agree with me on that ? Jan Warnqvist - Original Message - From: Keith Addison [EMAIL PROTECTED] To: biofuel@sustainablelists.org Sent: Friday, August 10, 2007 9:53 AM Subject: Re: [Biofuel] Glycerine Settling Time Hi Tom Hi Keith, Then if you do one-litre test batches first, especially with iffy batches of oil, Ops. I took Joe's point to be: If you have to re-process it is possible to use info from the QT to determine how much (how little) methanol you'll need to use. I also took that point, there were others though. It's a useful method, cheaper reprocessing, but I think we all agree that reprocessing itself is to be avoided if at all possible. Or I thought we did anyway. I think that both Joe and myself have standardize(d) the process so that passing the QT is the rule, not the exception. That's not what Joe said: It makes sense. Glycerin is an emulsifier. Have you ever tried dosing the batch again with a little methoxide? After you remove the glycerin it doesn't take much to get the last bit of the reaction to go and settle out the remaining glycerin. Of course this is well known already. Kenji and many others do straight base catalysis as a two stage deal. You can do a methanol test of sorts and the unreacted oil will settle out. Then you can use the measured amount of unreacted oil in the methanol test vial to estimate the percentage unreacted oil in your batch and dose accordingly with the stoichiometric amount of methoxide. Assume neutral oil for this calculation. Rod and I do this regularly if the batch fails the QT and it works like a charm. Will save you settling time in the long run. Rod and I do this regularly if the batch fails the QT and it works like a charm. That if makes it a little ambiguous, but the regularly bit puts a question-mark on what's the rule and what's the exception. Kenji and many others do straight base catalysis as a two stage deal. Less methanol notwithstanding, my question remains - why reprocess, as a standard procedure, instead of avoiding the problem in the first place? Could be wrong, but it sounds like Kenji and others might be doing this rather than doing a titration - you know the old line: There's no need for titration, just use 6.25 g. And then using the methanol test to try
Re: [Biofuel] Glycerine Settling Time
Hello Joe. There were probably small amounts of mono- and diglycerides left in the biodiesel, and/or possibly soaps which together are excellent emulsifiers. A strong acid will divide the glycerides into fatty acids and glycerine ,and the soaps into salts and fatty acids, which then goes into a fat phanse and an aquaeus phase, possibly with the salts in the bottom.' Best regards Jan - Original Message - From: Joe Street To: biofuel@sustainablelists.org Sent: Friday, August 10, 2007 3:45 PM Subject: Re: [Biofuel] Glycerine Settling Time Hi Jan; Ok your post agrees with what Andres said. So how do we explain Tom's experiment then? To recap (Tom correct me if I miss something here) he took washed esters that passed the methanol test and added water and (of course) no emulsion when agitated. Whatever mono and diglycerides were in the esters were small but present I assume, but yet no emusion. Then added some small quantity of glycerol ( which had been separated from the soaps, FFA and salts) and agitated again and did get an emulsion. I have had the feeling glycerin has usually been the cause of emulsion problems when I have had them. No doubt a poorly reacted batch is much more likely to have the problem but is that really due to the glycerides or is it glycerin which hasn't settled. Remember we started this discussion that the glycerin settles much slower in a poorly completed run. BTW as an addition to this discussion look what someone just posted on my yahoo group! Using glycerin cocktail to BREAK an emulsion. Now that's radical!!?? http://www.biodieselcommunity.org/breakingemulsions/ Joe Jan Warnqvist wrote: Hi evereybody. I feel obliged to enter this discussion. Pure glycerine is not a good emulsifier due to the fact that there are three OH-groups and that the carbon s in the first and third positions are surronded by two hydrogene atoms. This makes the glycerine hydrophilic in five places alltogether. However, the mono- and diglycerides are excellent emulsifiers. Only small amounts of these are sufficient to create stable emulsions. Would somebody agree with me on that ? Jan Warnqvist - Original Message - From: Keith Addison [EMAIL PROTECTED] To: biofuel@sustainablelists.org Sent: Friday, August 10, 2007 9:53 AM Subject: Re: [Biofuel] Glycerine Settling Time Hi Tom Hi Keith, Then if you do one-litre test batches first, especially with iffy batches of oil, Ops. I took Joe's point to be: If you have to re-process it is possible to use info from the QT to determine how much (how little) methanol you'll need to use. I also took that point, there were others though. It's a useful method, cheaper reprocessing, but I think we all agree that reprocessing itself is to be avoided if at all possible. Or I thought we did anyway. I think that both Joe and myself have standardize(d) the process so that passing the QT is the rule, not the exception. That's not what Joe said: It makes sense. Glycerin is an emulsifier. Have you ever tried dosing the batch again with a little methoxide? After you remove the glycerin it doesn't take much to get the last bit of the reaction to go and settle out the remaining glycerin. Of course this is well known already. Kenji and many others do straight base catalysis as a two stage deal. You can do a methanol test of sorts and the unreacted oil will settle out. Then you can use the measured amount of unreacted oil in the methanol test vial to estimate the percentage unreacted oil in your batch and dose accordingly with the stoichiometric amount of methoxide. Assume neutral oil for this calculation. Rod and I do this regularly if the batch fails the QT and it works like a charm. Will save you settling time in the long run. Rod and I do this regularly if the batch fails the QT and it works like a charm. That if makes it a little ambiguous, but the regularly bit puts a question-mark on what's the rule and what's the exception. Kenji and many others do straight base catalysis as a two stage deal. Less methanol notwithstanding, my question remains - why reprocess, as a standard procedure, instead of avoiding the problem in the first place? Could be wrong, but it sounds like Kenji and others might be doing this rather than doing a titration - you know the old line: There's no need for titration, just use 6.25 g. And then using the methanol test to try to fix the regularly ensuing disaster. A different version of that here in Japan is to put the stuff through a centrifuge, though the product still doesn't pass any quality test or standards test. What you describe is much the same as what I described, doing (whatever) tests during the processing, adjusting accordingly and conducting the whole thing as a single stage. From Joe's replies so far I can't tell if he (and Rod, and Kenji and many others) are doing it that way
Re: [Biofuel] Glycerine Settling Time
Hi Jan; Ok your post agrees with what Andres said. So how do we explain Tom's experiment then? To recap (Tom correct me if I miss something here) he took washed esters that passed the methanol test and added water and (of course) no emulsion when agitated. Whatever mono and diglycerides were in the esters were small but present I assume, but yet no emusion. Then added some small quantity of glycerol ( which had been separated from the soaps, FFA and salts) and agitated again and did get an emulsion. I have had the feeling glycerin has usually been the cause of emulsion problems when I have had them. No doubt a poorly reacted batch is much more likely to have the problem but is that really due to the glycerides or is it glycerin which hasn't settled. Remember we started this discussion that the glycerin settles much slower in a poorly completed run. BTW as an addition to this discussion look what someone just posted on my yahoo group! Using glycerin cocktail to BREAK an emulsion. Now that's radical!!?? http://www.biodieselcommunity.org/breakingemulsions/ Joe Jan Warnqvist wrote: Hi evereybody. I feel obliged to enter this discussion. Pure glycerine is not a good emulsifier due to the fact that there are three OH-groups and that the carbon s in the first and third positions are surronded by two hydrogene atoms. This makes the glycerine hydrophilic in five places alltogether. However, the mono- and diglycerides are excellent emulsifiers. Only small amounts of these are sufficient to create stable emulsions. Would somebody agree with me on that ? Jan Warnqvist - Original Message - From: Keith Addison [EMAIL PROTECTED] To: biofuel@sustainablelists.org Sent: Friday, August 10, 2007 9:53 AM Subject: Re: [Biofuel] Glycerine Settling Time Hi Tom Hi Keith, Then if you do one-litre test batches first, especially with iffy batches of oil, Ops. I took Joe's point to be: If you have to re-process it is possible to use info from the QT to determine how much (how little) methanol you'll need to use. I also took that point, there were others though. It's a useful method, cheaper reprocessing, but I think we all agree that reprocessing itself is to be avoided if at all possible. Or I thought we did anyway. I think that both Joe and myself have standardize(d) the process so that passing the QT is the rule, not the exception. That's not what Joe said: It makes sense. Glycerin is an emulsifier. Have you ever tried dosing the batch again with a little methoxide? After you remove the glycerin it doesn't take much to get the last bit of the reaction to go and settle out the remaining glycerin. Of course this is well known already. Kenji and many others do straight base catalysis as a two stage deal. You can do a methanol test of sorts and the unreacted oil will settle out. Then you can use the measured amount of unreacted oil in the methanol test vial to estimate the percentage unreacted oil in your batch and dose accordingly with the stoichiometric amount of methoxide. Assume neutral oil for this calculation. Rod and I do this regularly if the batch fails the QT and it works like a charm. Will save you settling time in the long run. Rod and I do this regularly if the batch fails the QT and it works like a charm. That if makes it a little ambiguous, but the regularly bit puts a question-mark on what's the rule and what's the exception. Kenji and many others do straight base catalysis as a two stage deal. Less methanol notwithstanding, my question remains - why reprocess, as a standard procedure, instead of avoiding the problem in the first place? Could be wrong, but it sounds like Kenji and others might be doing this rather than doing a titration - you know the old line: There's no need for titration, just use 6.25 g. And then using the methanol test to try to fix the regularly ensuing disaster. A different version of that here in Japan is to put the stuff through a centrifuge, though the product still doesn't pass any quality test or standards test. What you describe is much the same as what I described, doing (whatever) tests during the processing, adjusting accordingly and conducting the whole thing as a single stage. From Joe's replies so far I can't tell if he (and Rod, and Kenji and many others) are doing it that way or not, but it seems not: Your question (and mine): Don't you have to heat up the whole batch again? (Time and energy) Joe's reply: This is all done right after draining the glycerin. I leave the heater on during this period. Do the rough QT right away before wash test. Rough QT? Anyway, how long is it settling before he drains the glyc? I run a QT towards the end of the reaction because I do not want to re-process. Indeed not. It takes me a few minutes and I like the certainty of knowing the BD is good before I pump it into my
Re: [Biofuel] Glycerine Settling Time
Tom; It makes sense. Glycerin is an emulsifier. Have you ever tried dosing the batch again with a little methoxide? After you remove the glycerin it doesn't take much to get the last bit of the reaction to go and settle out the remaining glycerin. Of course this is well known already. Kenji and many others do straight base catalysis as a two stage deal. You can do a methanol test of sorts and the unreacted oil will settle out. Then you can use the measured amount of unreacted oil in the methanol test vial to estimate the percentage unreacted oil in your batch and dose accordingly with the stoichiometric amount of methoxide. Assume neutral oil for this calculation. Rod and I do this regularly if the batch fails the QT and it works like a charm. Will save you settling time in the long run. Big skies Joe Thomas Kelly wrote: Joe, I took a sample from my latest batch of BD destined for my boiler (failed QT; but very little residue dropped out). It had settled for almost 10 hrs. That was yesterday morning. Today there is a small, but noticable, bit of glycerine on the bottom. More settled out after the initial 10 hrs of settling. I don't have any results with good BD to compare it with. If it turns out that glycerine settles out slower from incomplete vs complete reactions, it would answer the question I asked about getting emulsions when I washed low quality BD after letting it settle overnight, but not getting emulsions when it settled for a few days to a week. It would also help with a friendly disagreement I have with a friend. He seems to think that unreacted glycerides will settle out of the BD given time. He has taken to going with about 16% (vol/vol) of methanol in his batches. His logic: Unreacted oil causes emulsions, right? The emulsions I get in the first wash after settling the BD overnight are due to the unreacted oil? When I let it settle for a week or more I don't get emulsions, therefore the unreacted oil must have settled out. More likely: Some unreacted glycerides are still there, but after a week of settling more of the glycerine has settled out. Even a small amount of glycerine compound the emulsifying effects of the unreacted glycerides . Yes? By the way, I always ask him Did you do a quality test? His answer: Oops, I forgot. Thanks Joe and Rod . for bringing this to my attention A push to make a lot of BD for heat is just around the corner. It might be best to include more settling time in the schedule. Tom - Original Message - *From:* Joe Street mailto:[EMAIL PROTECTED] *To:* biofuel@sustainablelists.org mailto:biofuel@sustainablelists.org *Sent:* Tuesday, August 07, 2007 3:02 PM *Subject:* Re: [Biofuel] Biofuel Quality Test Hey Tom; Take a sample from your fuel after settling 6-8 hrs and set it asside in a mason jar for the longer period and see what settles out. Rod believes that glycerin settles slower in a poorly completed reaction. I believe he is right. And yes it only takes a little glycerin to emulsify your wash. Joe Thomas Kelly wrote: Mike, I let mine settle for a week when I can. It washes much easier. I doubt that it does anything for an incomplete reaction though. That is to say, I don't think the unreacted oil will settle out. But: I have been wondering about something. When I started making BD it would never pass the methanol quality test. I inevitably got emulsions in the wash. Now, when I make BD for my oil-fired boiler, I use only about 16-17% (vol/vol) of methanol. The BD does not pass the quality test, but I don't have the same emulsion problems. Is it because I let it settle longer (24+ hours vs 6 - 8 hrs)? Does the presence of a small amount of glycerine/soaps make that much of a difference when trying to wash BD from an incomplete reaction? Tom - Original Message - From: Mike Weaver [EMAIL PROTECTED] To: biofuel@sustainablelists.org Sent: Monday, August 06, 2007 2:46 PM Subject: Re: [Biofuel] Biofuel Quality Test FWIW - I let the batch settle for a week or so (the lazy man's way) and that also seems to help w/ this. Thomas Kelly wrote: Shawn, I suspect that the dense substance at the bottom of the flask was unreacted glycerides, indicating an incomplete reaction. I now drain a sample of the mix towards the end of processing. - Shut off the pump - Drain a sample and turn the pump back on - Allow the glycerin to settle for a few minutes - Perform Jan W's quality test on the top (crude BD) layer There is still glycerin in the mix, but if I have succeeded in getting a complete reaction, I do not get
Re: [Biofuel] Glycerine Settling Time
Joe, You wrote: Have you ever tried dosing the batch again with a little methoxide? After you remove the glycerin it doesn't take much to get the last bit of the reaction to go and settle out the remaining glycerin. I've been concerned about the excess methanol and the catalytic caustic that will leave with the glycerin I remove. You seem to be suggesting re-processing the BD using info from the QT. Instead of adding 10% (vol/vol) methanol, use an amount that correlates to the volume of unreacted oil (from QT). Ex QT suggests 8% unreacted oil in a 100L batch = 8 L of unreacted oil in the batch. Add 1.6L of methanol (20% vol/vol of the unreacted oil) and re-process. (Much better than the 10L normally required for re-processing). Have I got it right? Do you still have to add 3.5g of lye (or KOH equivalent)/L ? If so, is it 3.5g lye per liter of unreacted oil (calculated from QT) or per L of batch? Don't you have to heat up the whole batch again? (Time and energy) If so, I suggest my way. Towards the end of the reaction, interrupt the process and test the BD*. If it fails the QT add more methanol** and let the reaction continue for a while. * When I drain the sample to be tested, I allow some to flow before taking the sample. In case there was oil in my drain plug I won't get a false negative on the QT. ** I have simply added a liter or two based loosely on the QT. I will now quantify based on the QT and be more accurate (Thanks). Kenji and many others do straight base catalysis as a two stage deal. Two Stage Base/Base Method? I know of someone who uses it; no titration --- consistently good BD. It seems to be a bit more time-consuming and uses more energy and caustic than my simple (some would say primitive) single stage base method. Big Lunch, Tom - Original Message - From: Joe Street To: biofuel@sustainablelists.org Sent: Thursday, August 09, 2007 11:30 AM Subject: Re: [Biofuel] Glycerine Settling Time Tom; It makes sense. Glycerin is an emulsifier. Have you ever tried dosing the batch again with a little methoxide? After you remove the glycerin it doesn't take much to get the last bit of the reaction to go and settle out the remaining glycerin. Of course this is well known already. Kenji and many others do straight base catalysis as a two stage deal. You can do a methanol test of sorts and the unreacted oil will settle out. Then you can use the measured amount of unreacted oil in the methanol test vial to estimate the percentage unreacted oil in your batch and dose accordingly with the stoichiometric amount of methoxide. Assume neutral oil for this calculation. Rod and I do this regularly if the batch fails the QT and it works like a charm. Will save you settling time in the long run. Big skies Joe Thomas Kelly wrote: Joe, I took a sample from my latest batch of BD destined for my boiler (failed QT; but very little residue dropped out). It had settled for almost 10 hrs. That was yesterday morning. Today there is a small, but noticable, bit of glycerine on the bottom. More settled out after the initial 10 hrs of settling. I don't have any results with good BD to compare it with. If it turns out that glycerine settles out slower from incomplete vs complete reactions, it would answer the question I asked about getting emulsions when I washed low quality BD after letting it settle overnight, but not getting emulsions when it settled for a few days to a week. It would also help with a friendly disagreement I have with a friend. He seems to think that unreacted glycerides will settle out of the BD given time. He has taken to going with about 16% (vol/vol) of methanol in his batches. His logic: Unreacted oil causes emulsions, right? The emulsions I get in the first wash after settling the BD overnight are due to the unreacted oil? When I let it settle for a week or more I don't get emulsions, therefore the unreacted oil must have settled out. More likely: Some unreacted glycerides are still there, but after a week of settling more of the glycerine has settled out. Even a small amount of glycerine compound the emulsifying effects of the unreacted glycerides . Yes? By the way, I always ask him Did you do a quality test? His answer: Oops, I forgot. Thanks Joe and Rod . for bringing this to my attention A push to make a lot of BD for heat is just around the corner. It might be best to include more settling time in the schedule. Tom - Original Message - From: Joe Street To: biofuel@sustainablelists.org Sent: Tuesday, August 07, 2007 3:02 PM Subject
Re: [Biofuel] Glycerine Settling Time
From the moment that I decided to left the reacted mixture to settle two days I never had a batch below standards. Is a 5,000 lt reactor and the settling tank is separated. - Original Message - From: Thomas Kelly To: biofuel@sustainablelists.org Sent: Thursday, August 09, 2007 1:10 PM Subject: Re: [Biofuel] Glycerine Settling Time Joe, You wrote: Have you ever tried dosing the batch again with a little methoxide? After you remove the glycerin it doesn't take much to get the last bit of the reaction to go and settle out the remaining glycerin. I've been concerned about the excess methanol and the catalytic caustic that will leave with the glycerin I remove. You seem to be suggesting re-processing the BD using info from the QT. Instead of adding 10% (vol/vol) methanol, use an amount that correlates to the volume of unreacted oil (from QT). Ex QT suggests 8% unreacted oil in a 100L batch = 8 L of unreacted oil in the batch. Add 1.6L of methanol (20% vol/vol of the unreacted oil) and re-process. (Much better than the 10L normally required for re-processing). Have I got it right? Do you still have to add 3.5g of lye (or KOH equivalent)/L ? If so, is it 3.5g lye per liter of unreacted oil (calculated from QT) or per L of batch? Don't you have to heat up the whole batch again? (Time and energy) If so, I suggest my way. Towards the end of the reaction, interrupt the process and test the BD*. If it fails the QT add more methanol** and let the reaction continue for a while. * When I drain the sample to be tested, I allow some to flow before taking the sample. In case there was oil in my drain plug I won't get a false negative on the QT. ** I have simply added a liter or two based loosely on the QT. I will now quantify based on the QT and be more accurate (Thanks). Kenji and many others do straight base catalysis as a two stage deal. Two Stage Base/Base Method? I know of someone who uses it; no titration --- consistently good BD. It seems to be a bit more time-consuming and uses more energy and caustic than my simple (some would say primitive) single stage base method. Big Lunch, Tom - Original Message - From: Joe Street To: biofuel@sustainablelists.org Sent: Thursday, August 09, 2007 11:30 AM Subject: Re: [Biofuel] Glycerine Settling Time Tom; It makes sense. Glycerin is an emulsifier. Have you ever tried dosing the batch again with a little methoxide? After you remove the glycerin it doesn't take much to get the last bit of the reaction to go and settle out the remaining glycerin. Of course this is well known already. Kenji and many others do straight base catalysis as a two stage deal. You can do a methanol test of sorts and the unreacted oil will settle out. Then you can use the measured amount of unreacted oil in the methanol test vial to estimate the percentage unreacted oil in your batch and dose accordingly with the stoichiometric amount of methoxide. Assume neutral oil for this calculation. Rod and I do this regularly if the batch fails the QT and it works like a charm. Will save you settling time in the long run. Big skies Joe Thomas Kelly wrote: Joe, I took a sample from my latest batch of BD destined for my boiler (failed QT; but very little residue dropped out). It had settled for almost 10 hrs. That was yesterday morning. Today there is a small, but noticable, bit of glycerine on the bottom. More settled out after the initial 10 hrs of settling. I don't have any results with good BD to compare it with. If it turns out that glycerine settles out slower from incomplete vs complete reactions, it would answer the question I asked about getting emulsions when I washed low quality BD after letting it settle overnight, but not getting emulsions when it settled for a few days to a week. It would also help with a friendly disagreement I have with a friend. He seems to think that unreacted glycerides will settle out of the BD given time. He has taken to going with about 16% (vol/vol) of methanol in his batches. His logic: Unreacted oil causes emulsions, right? The emulsions I get in the first wash after settling the BD overnight are due to the unreacted oil? When I let it settle for a week or more I don't get emulsions, therefore the unreacted oil must have settled out. More likely: Some unreacted glycerides are still there, but after a week of settling more of the glycerine has settled out. Even a small amount of glycerine compound the emulsifying effects of the unreacted glycerides . Yes? By the way, I always ask him Did you do a quality test? His answer: Oops, I forgot. Thanks
Re: [Biofuel] Glycerine Settling Time
See below Thomas Kelly wrote: Joe, You wrote: Have you ever tried dosing the batch again with a little methoxide? After you remove the glycerin it doesn't take much to get the last bit of the reaction to go and settle out the remaining glycerin. I've been concerned about the excess methanol and the catalytic caustic that will leave with the glycerin I remove. It is in the glycerin anyways, but the glycerin is stopping the reaction so removing it shifts the equilibrium point in favour of completion. You seem to be suggesting re-processing the BD using info from the QT. Yep. There will be 1-2% v/v methanol in the esters anyways and the remaining excess is disolved in the glycerin. Instead of adding 10% (vol/vol) methanol, use an amount that correlates to the volume of unreacted oil (from QT). Ex QT suggests 8% unreacted oil in a 100L batch = 8 L of unreacted oil in the batch. Add 1.6L of methanol (20% vol/vol of the unreacted oil) and re-process. (Much better than the 10L normally required for re-processing). Have I got it right? Yes Do you still have to add 3.5g of lye (or KOH equivalent)/L ? If so, is it 3.5g lye per liter of unreacted oil (calculated from QT) or per L of batch? Yes 28 g or 40 etc. Don't you have to heat up the whole batch again? (Time and energy) This is all done right after draining the glycerin. I leave the heater on during this period. Do the rough QT right away before wash test. BTW I still do the 'real' QT after all washing and drying are done. If so, I suggest my way. Towards the end of the reaction, interrupt the process and test the BD*. If it fails the QT add more methanol** and let the reaction continue for a while. Well basically yes that's what I'm doing but have drained the glycerin and doing the test with methanol shows you exactly what percentage unreacted stuff you've got so add methanol and 'X'OH for that amount of oil. You can add the remains to the reaction or next batch of course. * When I drain the sample to be tested, I allow some to flow before taking the sample. In case there was oil in my drain plug I won't get a false negative on the QT. ** I have simply added a liter or two based loosely on the QT. I will now quantify based on the QT and be more accurate (Thanks). Kenji and many others do straight base catalysis as a two stage deal. Two Stage Base/Base Method? I know of someone who uses it; no titration --- consistently good BD. I wouldn't skip the titration but rather do the base step in two stages and remove glycerin in between. It seems to be a bit more time-consuming and uses more energy and caustic than my simple (some would say primitive) single stage base method. Yes a little more time since two settling periods but it's hard to get it just perfect with one stage anyways so then some repro is called for andtime. Big Lunch, Tom LOL U funny! Cheers Joe ___ Biofuel mailing list Biofuel@sustainablelists.org http://sustainablelists.org/mailman/listinfo/biofuel_sustainablelists.org Biofuel at Journey to Forever: http://journeytoforever.org/biofuel.html Search the combined Biofuel and Biofuels-biz list archives (50,000 messages): http://www.mail-archive.com/biofuel@sustainablelists.org/
Re: [Biofuel] Glycerine Settling Time
Joe, For the sake of precise concepts, gliceryn is NOT an emulsifier. Emulsifiers contains a clear lipofilic and hidrofilic zones in the molecule. Which is an emulsifier is the partially reacted mono or di-glicerides, but in a crystal clear liquid there are not emulsions or dispersions. Glycerin is dissolved in the BD and separates from the liquid BD phase with time. - Original Message - From: Joe Street To: biofuel@sustainablelists.org Sent: Thursday, August 09, 2007 11:30 AM Subject: Re: [Biofuel] Glycerine Settling Time Tom; It makes sense. Glycerin is an emulsifier. Have you ever tried dosing the batch again with a little methoxide? After you remove the glycerin it doesn't take much to get the last bit of the reaction to go and settle out the remaining glycerin. Of course this is well known already. Kenji and many others do straight base catalysis as a two stage deal. You can do a methanol test of sorts and the unreacted oil will settle out. Then you can use the measured amount of unreacted oil in the methanol test vial to estimate the percentage unreacted oil in your batch and dose accordingly with the stoichiometric amount of methoxide. Assume neutral oil for this calculation. Rod and I do this regularly if the batch fails the QT and it works like a charm. Will save you settling time in the long run. Big skies Joe Thomas Kelly wrote: Joe, I took a sample from my latest batch of BD destined for my boiler (failed QT; but very little residue dropped out). It had settled for almost 10 hrs. That was yesterday morning. Today there is a small, but noticable, bit of glycerine on the bottom. More settled out after the initial 10 hrs of settling. I don't have any results with good BD to compare it with. If it turns out that glycerine settles out slower from incomplete vs complete reactions, it would answer the question I asked about getting emulsions when I washed low quality BD after letting it settle overnight, but not getting emulsions when it settled for a few days to a week. It would also help with a friendly disagreement I have with a friend. He seems to think that unreacted glycerides will settle out of the BD given time. He has taken to going with about 16% (vol/vol) of methanol in his batches. His logic: Unreacted oil causes emulsions, right? The emulsions I get in the first wash after settling the BD overnight are due to the unreacted oil? When I let it settle for a week or more I don't get emulsions, therefore the unreacted oil must have settled out. More likely: Some unreacted glycerides are still there, but after a week of settling more of the glycerine has settled out. Even a small amount of glycerine compound the emulsifying effects of the unreacted glycerides . Yes? By the way, I always ask him Did you do a quality test? His answer: Oops, I forgot. Thanks Joe and Rod . for bringing this to my attention A push to make a lot of BD for heat is just around the corner. It might be best to include more settling time in the schedule. Tom - Original Message - From: Joe Street To: biofuel@sustainablelists.org Sent: Tuesday, August 07, 2007 3:02 PM Subject: Re: [Biofuel] Biofuel Quality Test Hey Tom; Take a sample from your fuel after settling 6-8 hrs and set it asside in a mason jar for the longer period and see what settles out. Rod believes that glycerin settles slower in a poorly completed reaction. I believe he is right. And yes it only takes a little glycerin to emulsify your wash. Joe Thomas Kelly wrote: Mike, I let mine settle for a week when I can. It washes much easier. I doubt that it does anything for an incomplete reaction though. That is to say, I don't think the unreacted oil will settle out. But: I have been wondering about something. When I started making BD it would never pass the methanol quality test. I inevitably got emulsions in the wash. Now, when I make BD for my oil-fired boiler, I use only about 16-17% (vol/vol) of methanol. The BD does not pass the quality test, but I don't have the same emulsion problems. Is it because I let it settle longer (24+ hours vs 6 - 8 hrs)? Does the presence of a small amount of glycerine/soaps make that much of a difference when trying to wash BD from an incomplete reaction? Tom - Original Message - From: Mike Weaver [EMAIL PROTECTED] To: biofuel@sustainablelists.org Sent: Monday, August 06, 2007 2:46 PM Subject: Re: [Biofuel] Biofuel Quality Test FWIW - I let the batch settle for a week or so (the lazy man's way
Re: [Biofuel] Glycerine Settling Time
Andres, For the sake of precise concepts, gliceryn is NOT an emulsifier. I have used the glycerine cocktail to de-grease a barrel. Is it the caustic (KOH) that reacts with the grease? Also: If I do a wash test on BD from a complete reaction no mono- or di- glycerides, but with some glycerine cocktail still present, I get an emulsion. Let the glycerine settle, no emulsion. Could you explain? Tom - Original Message - From: Andres Secco To: biofuel@sustainablelists.org Sent: Thursday, August 09, 2007 1:55 PM Subject: Re: [Biofuel] Glycerine Settling Time Joe, For the sake of precise concepts, gliceryn is NOT an emulsifier. Emulsifiers contains a clear lipofilic and hidrofilic zones in the molecule. Which is an emulsifier is the partially reacted mono or di-glicerides, but in a crystal clear liquid there are not emulsions or dispersions. Glycerin is dissolved in the BD and separates from the liquid BD phase with time. - Original Message - From: Joe Street To: biofuel@sustainablelists.org Sent: Thursday, August 09, 2007 11:30 AM Subject: Re: [Biofuel] Glycerine Settling Time Tom; It makes sense. Glycerin is an emulsifier. Have you ever tried dosing the batch again with a little methoxide? After you remove the glycerin it doesn't take much to get the last bit of the reaction to go and settle out the remaining glycerin. Of course this is well known already. Kenji and many others do straight base catalysis as a two stage deal. You can do a methanol test of sorts and the unreacted oil will settle out. Then you can use the measured amount of unreacted oil in the methanol test vial to estimate the percentage unreacted oil in your batch and dose accordingly with the stoichiometric amount of methoxide. Assume neutral oil for this calculation. Rod and I do this regularly if the batch fails the QT and it works like a charm. Will save you settling time in the long run. Big skies Joe Thomas Kelly wrote: Joe, I took a sample from my latest batch of BD destined for my boiler (failed QT; but very little residue dropped out). It had settled for almost 10 hrs. That was yesterday morning. Today there is a small, but noticable, bit of glycerine on the bottom. More settled out after the initial 10 hrs of settling. I don't have any results with good BD to compare it with. If it turns out that glycerine settles out slower from incomplete vs complete reactions, it would answer the question I asked about getting emulsions when I washed low quality BD after letting it settle overnight, but not getting emulsions when it settled for a few days to a week. It would also help with a friendly disagreement I have with a friend. He seems to think that unreacted glycerides will settle out of the BD given time. He has taken to going with about 16% (vol/vol) of methanol in his batches. His logic: Unreacted oil causes emulsions, right? The emulsions I get in the first wash after settling the BD overnight are due to the unreacted oil? When I let it settle for a week or more I don't get emulsions, therefore the unreacted oil must have settled out. More likely: Some unreacted glycerides are still there, but after a week of settling more of the glycerine has settled out. Even a small amount of glycerine compound the emulsifying effects of the unreacted glycerides . Yes? By the way, I always ask him Did you do a quality test? His answer: Oops, I forgot. Thanks Joe and Rod . for bringing this to my attention A push to make a lot of BD for heat is just around the corner. It might be best to include more settling time in the schedule. Tom - Original Message - From: Joe Street To: biofuel@sustainablelists.org Sent: Tuesday, August 07, 2007 3:02 PM Subject: Re: [Biofuel] Biofuel Quality Test Hey Tom; Take a sample from your fuel after settling 6-8 hrs and set it asside in a mason jar for the longer period and see what settles out. Rod believes that glycerin settles slower in a poorly completed reaction. I believe he is right. And yes it only takes a little glycerin to emulsify your wash. Joe Thomas Kelly wrote: Mike, I let mine settle for a week when I can. It washes much easier. I doubt that it does anything for an incomplete reaction though. That is to say, I don't think the unreacted oil will settle out. But: I have been wondering about something. When I started making BD it would never pass the methanol quality test. I inevitably got
Re: [Biofuel] Glycerine Settling Time
Ooops I gues you are right technically glycerin is not an emulsifier so I shouldn't have used that term. Thanks for correcting me. It does however have a big effect on the ability of water and esters to turn into an emulsion. I said that because as you know when you get glycerin even a tiny amount on your skin and go to wash it off it has that super slippery feel which means the surface tension of the water has been reduced dramatically. I think that's why it makes emulsions, perhaps the proper term is surfactant then? Joe Andres Secco wrote: Joe, For the sake of precise concepts, gliceryn is NOT an emulsifier. Emulsifiers contains a clear lipofilic and hidrofilic zones in the molecule. Which is an emulsifier is the partially reacted mono or di-glicerides, but in a crystal clear liquid there are not emulsions or dispersions. Glycerin is dissolved in the BD and separates from the liquid BD phase with time. - Original Message - *From:* Joe Street mailto:[EMAIL PROTECTED] *To:* biofuel@sustainablelists.org mailto:biofuel@sustainablelists.org *Sent:* Thursday, August 09, 2007 11:30 AM *Subject:* Re: [Biofuel] Glycerine Settling Time Tom; It makes sense. Glycerin is an emulsifier. Have you ever tried dosing the batch again with a little methoxide? After you remove the glycerin it doesn't take much to get the last bit of the reaction to go and settle out the remaining glycerin. Of course this is well known already. Kenji and many others do straight base catalysis as a two stage deal. You can do a methanol test of sorts and the unreacted oil will settle out. Then you can use the measured amount of unreacted oil in the methanol test vial to estimate the percentage unreacted oil in your batch and dose accordingly with the stoichiometric amount of methoxide. Assume neutral oil for this calculation. Rod and I do this regularly if the batch fails the QT and it works like a charm. Will save you settling time in the long run. Big skies Joe Thomas Kelly wrote: Joe, I took a sample from my latest batch of BD destined for my boiler (failed QT; but very little residue dropped out). It had settled for almost 10 hrs. That was yesterday morning. Today there is a small, but noticable, bit of glycerine on the bottom. More settled out after the initial 10 hrs of settling. I don't have any results with good BD to compare it with. If it turns out that glycerine settles out slower from incomplete vs complete reactions, it would answer the question I asked about getting emulsions when I washed low quality BD after letting it settle overnight, but not getting emulsions when it settled for a few days to a week. It would also help with a friendly disagreement I have with a friend. He seems to think that unreacted glycerides will settle out of the BD given time. He has taken to going with about 16% (vol/vol) of methanol in his batches. His logic: Unreacted oil causes emulsions, right? The emulsions I get in the first wash after settling the BD overnight are due to the unreacted oil? When I let it settle for a week or more I don't get emulsions, therefore the unreacted oil must have settled out. More likely: Some unreacted glycerides are still there, but after a week of settling more of the glycerine has settled out. Even a small amount of glycerine compound the emulsifying effects of the unreacted glycerides . Yes? By the way, I always ask him Did you do a quality test? His answer: Oops, I forgot. Thanks Joe and Rod . for bringing this to my attention A push to make a lot of BD for heat is just around the corner. It might be best to include more settling time in the schedule. Tom - Original Message - *From:* Joe Street mailto:[EMAIL PROTECTED] *To:* biofuel@sustainablelists.org mailto:biofuel@sustainablelists.org *Sent:* Tuesday, August 07, 2007 3:02 PM *Subject:* Re: [Biofuel] Biofuel Quality Test Hey Tom; Take a sample from your fuel after settling 6-8 hrs and set it asside in a mason jar for the longer period and see what settles out. Rod believes that glycerin settles slower in a poorly completed reaction. I believe he is right. And yes it only takes a little glycerin to emulsify your wash. Joe Thomas Kelly wrote: Mike, I let mine settle for a week when I can. It washes much easier. I doubt that it does anything for an incomplete reaction though. That is to say, I don't
Re: [Biofuel] Glycerine Settling Time
Hi Joe Tom; It makes sense. Glycerin is an emulsifier. Have you ever tried dosing the batch again with a little methoxide? After you remove the glycerin it doesn't take much to get the last bit of the reaction to go and settle out the remaining glycerin. Of course this is well known already. Kenji and many others do straight base catalysis as a two stage deal. You can do a methanol test of sorts and the unreacted oil will settle out. Then you can use the measured amount of unreacted oil in the methanol test vial to estimate the percentage unreacted oil in your batch and dose accordingly with the stoichiometric amount of methoxide. Assume neutral oil for this calculation. Rod and I do this regularly if the batch fails the QT and it works like a charm. Will save you settling time in the long run. Well, settling time is free. Acid-base aside, there's the two-stage base-base process, which quite a lot of people use and like, but otherwise why do more than one stage? Do you mean two separate stages, with a methanol test in between? So you process it twice? Plus extra methanol. Why not do it in a single phase? Todd Swearingen once suggested this here (discussing mixing pump sizes): To judge an appropriate reaction time, pull an exact amount of fluid (200 ml would suffice) out of the reaction stream every half-hour or hour after an arbitrary initial ~1 hour reaction period. Presuming that the contents of the reactor are kept homogenous from the pump flow, the volume of the glycerol cocktail that settles out of each sample will give you a fair gauge as to when your reaction completed. The suggestion would be to continue the reaction for ~1/2 hour beyond the point where your glyc cocktail volume stabilized. That works. Then, surely, you can standardise the process, with the only variable the amount of lye according to the titration level. Then if you do one-litre test batches first, especially with iffy batches of oil, and you have a clear idea of how your test-batch processing relates to your full-scale processing, life should be easier and there shouldn't be any batches failing the QT. What did I miss? Big skies :-) And broad horizons. Keith Joe Thomas Kelly wrote: Joe, I took a sample from my latest batch of BD destined for my boiler (failed QT; but very little residue dropped out). It had settled for almost 10 hrs. That was yesterday morning. Today there is a small, but noticable, bit of glycerine on the bottom. More settled out after the initial 10 hrs of settling. I don't have any results with good BD to compare it with. If it turns out that glycerine settles out slower from incomplete vs complete reactions, it would answer the question I asked about getting emulsions when I washed low quality BD after letting it settle overnight, but not getting emulsions when it settled for a few days to a week. It would also help with a friendly disagreement I have with a friend. He seems to think that unreacted glycerides will settle out of the BD given time. He has taken to going with about 16% (vol/vol) of methanol in his batches. His logic: Unreacted oil causes emulsions, right? The emulsions I get in the first wash after settling the BD overnight are due to the unreacted oil? When I let it settle for a week or more I don't get emulsions, therefore the unreacted oil must have settled out. More likely: Some unreacted glycerides are still there, but after a week of settling more of the glycerine has settled out. Even a small amount of glycerine compound the emulsifying effects of the unreacted glycerides . Yes? By the way, I always ask him Did you do a quality test? His answer: Oops, I forgot. Thanks Joe and Rod . for bringing this to my attention A push to make a lot of BD for heat is just around the corner. It might be best to include more settling time in the schedule. Tom - Original Message - From: mailto:[EMAIL PROTECTED]Joe Street To: mailto:biofuel@sustainablelists.orgbiofuel@sustainablelists.org Sent: Tuesday, August 07, 2007 3:02 PM Subject: Re: [Biofuel] Biofuel Quality Test Hey Tom; Take a sample from your fuel after settling 6-8 hrs and set it asside in a mason jar for the longer period and see what settles out. Rod believes that glycerin settles slower in a poorly completed reaction. I believe he is right. And yes it only takes a little glycerin to emulsify your wash. Joe Thomas Kelly wrote: Mike, I let mine settle for a week when I can. It washes much easier. I doubt that it does anything for an incomplete reaction though. That is to say, I don't think the unreacted oil will settle out. But: I have been wondering about something. When I started making BD it would never pass the methanol quality test. I inevitably got emulsions in the wash. Now, when I make BD for my oil-fired boiler, I use
Re: [Biofuel] Glycerine Settling Time
Andres, Emulsifiers contains a clear lipofilic and hidrofilic zones in the molecule. In mono- and di- glycerides the glycerin supplies the hydrophilic zone and the fatty acid chain(s) supply the hydrophobic (lipophilic) zones. The -OH groups in the glycerin give it regions of charge making it hydrophilic. In an aquous solution wouldn't these groups rotate towards the water exposing hydrocarbons (hydrophobic) to the BD? I just tried forming an emulsion with veg oil and tap water. The oil rose to the top. I added glycerine that was split from the glycerine cocktail using Phosphoric Acid. It has no soaps, FFA's, methanol or KOH. I shook the bottle and the oil and water did not separate . an emulsion? I then added some vinegar. The emulsion broke. Glycerine seems to be an emulsifier. Am I missing something? Tom - Original Message - From: Andres Secco To: biofuel@sustainablelists.org Sent: Thursday, August 09, 2007 1:55 PM Subject: Re: [Biofuel] Glycerine Settling Time Joe, For the sake of precise concepts, gliceryn is NOT an emulsifier. Emulsifiers contains a clear lipofilic and hidrofilic zones in the molecule. Which is an emulsifier is the partially reacted mono or di-glicerides, but in a crystal clear liquid there are not emulsions or dispersions. Glycerin is dissolved in the BD and separates from the liquid BD phase with time. - Original Message - From: Joe Street To: biofuel@sustainablelists.org Sent: Thursday, August 09, 2007 11:30 AM Subject: Re: [Biofuel] Glycerine Settling Time Tom; It makes sense. Glycerin is an emulsifier. Have you ever tried dosing the batch again with a little methoxide? After you remove the glycerin it doesn't take much to get the last bit of the reaction to go and settle out the remaining glycerin. Of course this is well known already. Kenji and many others do straight base catalysis as a two stage deal. You can do a methanol test of sorts and the unreacted oil will settle out. Then you can use the measured amount of unreacted oil in the methanol test vial to estimate the percentage unreacted oil in your batch and dose accordingly with the stoichiometric amount of methoxide. Assume neutral oil for this calculation. Rod and I do this regularly if the batch fails the QT and it works like a charm. Will save you settling time in the long run. Big skies Joe Thomas Kelly wrote: Joe, I took a sample from my latest batch of BD destined for my boiler (failed QT; but very little residue dropped out). It had settled for almost 10 hrs. That was yesterday morning. Today there is a small, but noticable, bit of glycerine on the bottom. More settled out after the initial 10 hrs of settling. I don't have any results with good BD to compare it with. If it turns out that glycerine settles out slower from incomplete vs complete reactions, it would answer the question I asked about getting emulsions when I washed low quality BD after letting it settle overnight, but not getting emulsions when it settled for a few days to a week. It would also help with a friendly disagreement I have with a friend. He seems to think that unreacted glycerides will settle out of the BD given time. He has taken to going with about 16% (vol/vol) of methanol in his batches. His logic: Unreacted oil causes emulsions, right? The emulsions I get in the first wash after settling the BD overnight are due to the unreacted oil? When I let it settle for a week or more I don't get emulsions, therefore the unreacted oil must have settled out. More likely: Some unreacted glycerides are still there, but after a week of settling more of the glycerine has settled out. Even a small amount of glycerine compound the emulsifying effects of the unreacted glycerides . Yes? By the way, I always ask him Did you do a quality test? His answer: Oops, I forgot. Thanks Joe and Rod . for bringing this to my attention A push to make a lot of BD for heat is just around the corner. It might be best to include more settling time in the schedule. Tom - Original Message - From: Joe Street To: biofuel@sustainablelists.org Sent: Tuesday, August 07, 2007 3:02 PM Subject: Re: [Biofuel] Biofuel Quality Test Hey Tom; Take a sample from your fuel after settling 6-8 hrs and set it asside in a mason jar for the longer period and see what settles out. Rod believes that glycerin settles slower in a poorly completed
Re: [Biofuel] Glycerine Settling Time
Kewl Tom; You are ans experimentalist like myself. How much oil/ water and how many drops of glycerol did it take to create the emulsion? Joe Thomas Kelly wrote: Andres, Emulsifiers contains a clear lipofilic and hidrofilic zones in the molecule. In mono- and di- glycerides the glycerin supplies the hydrophilic zone and the fatty acid chain(s) supply the hydrophobic (lipophilic) zones. The -OH groups in the glycerin give it regions of charge making it hydrophilic. In an aquous solution wouldn't these groups rotate towards the water exposing hydrocarbons (hydrophobic) to the BD? I just tried forming an emulsion with veg oil and tap water. The oil rose to the top. I added glycerine that was split from the glycerine cocktail using Phosphoric Acid. It has no soaps, FFA's, methanol or KOH. I shook the bottle and the oil and water did not separate . an emulsion? I then added some vinegar. The emulsion broke. Glycerine seems to be an emulsifier. Am I missing something? Tom - Original Message - *From:* Andres Secco mailto:[EMAIL PROTECTED] *To:* biofuel@sustainablelists.org mailto:biofuel@sustainablelists.org *Sent:* Thursday, August 09, 2007 1:55 PM *Subject:* Re: [Biofuel] Glycerine Settling Time Joe, For the sake of precise concepts, gliceryn is NOT an emulsifier. Emulsifiers contains a clear lipofilic and hidrofilic zones in the molecule. Which is an emulsifier is the partially reacted mono or di-glicerides, but in a crystal clear liquid there are not emulsions or dispersions. Glycerin is dissolved in the BD and separates from the liquid BD phase with time. - Original Message - *From:* Joe Street mailto:[EMAIL PROTECTED] *To:* biofuel@sustainablelists.org mailto:biofuel@sustainablelists.org *Sent:* Thursday, August 09, 2007 11:30 AM *Subject:* Re: [Biofuel] Glycerine Settling Time Tom; It makes sense. Glycerin is an emulsifier. Have you ever tried dosing the batch again with a little methoxide? After you remove the glycerin it doesn't take much to get the last bit of the reaction to go and settle out the remaining glycerin. Of course this is well known already. Kenji and many others do straight base catalysis as a two stage deal. You can do a methanol test of sorts and the unreacted oil will settle out. Then you can use the measured amount of unreacted oil in the methanol test vial to estimate the percentage unreacted oil in your batch and dose accordingly with the stoichiometric amount of methoxide. Assume neutral oil for this calculation. Rod and I do this regularly if the batch fails the QT and it works like a charm. Will save you settling time in the long run. Big skies Joe Thomas Kelly wrote: Joe, I took a sample from my latest batch of BD destined for my boiler (failed QT; but very little residue dropped out). It had settled for almost 10 hrs. That was yesterday morning. Today there is a small, but noticable, bit of glycerine on the bottom. More settled out after the initial 10 hrs of settling. I don't have any results with good BD to compare it with. If it turns out that glycerine settles out slower from incomplete vs complete reactions, it would answer the question I asked about getting emulsions when I washed low quality BD after letting it settle overnight, but not getting emulsions when it settled for a few days to a week. It would also help with a friendly disagreement I have with a friend. He seems to think that unreacted glycerides will settle out of the BD given time. He has taken to going with about 16% (vol/vol) of methanol in his batches. His logic: Unreacted oil causes emulsions, right? The emulsions I get in the first wash after settling the BD overnight are due to the unreacted oil? When I let it settle for a week or more I don't get emulsions, therefore the unreacted oil must have settled out. More likely: Some unreacted glycerides are still there, but after a week of settling more of the glycerine has settled out. Even a small amount of glycerine compound the emulsifying effects of the unreacted glycerides . Yes? By the way, I always ask him Did you do a quality test? His answer: Oops, I forgot. Thanks Joe and Rod . for bringing this to my
Re: [Biofuel] Glycerine Settling Time
Come on Joe! You're giving me more credit than I deserve. I didn't measure . the old little of this and a little of that method. I did use a graduated pipette to draw the glycerine out of the bottle. If it's important I can do it again. I have plenty of tap water and quite a bit of veg oil. By the way, I also tried it with isopropanol (similar in size to glycerine but with only one -OH group) It seemed to work there as well. Tom - Original Message - From: Joe Street To: biofuel@sustainablelists.org Sent: Thursday, August 09, 2007 3:58 PM Subject: Re: [Biofuel] Glycerine Settling Time Kewl Tom; You are ans experimentalist like myself. How much oil/ water and how many drops of glycerol did it take to create the emulsion? Joe Thomas Kelly wrote: Andres, Emulsifiers contains a clear lipofilic and hidrofilic zones in the molecule. In mono- and di- glycerides the glycerin supplies the hydrophilic zone and the fatty acid chain(s) supply the hydrophobic (lipophilic) zones. The -OH groups in the glycerin give it regions of charge making it hydrophilic. In an aquous solution wouldn't these groups rotate towards the water exposing hydrocarbons (hydrophobic) to the BD? I just tried forming an emulsion with veg oil and tap water. The oil rose to the top. I added glycerine that was split from the glycerine cocktail using Phosphoric Acid. It has no soaps, FFA's, methanol or KOH. I shook the bottle and the oil and water did not separate . an emulsion? I then added some vinegar. The emulsion broke. Glycerine seems to be an emulsifier. Am I missing something? Tom - Original Message - From: Andres Secco To: biofuel@sustainablelists.org Sent: Thursday, August 09, 2007 1:55 PM Subject: Re: [Biofuel] Glycerine Settling Time Joe, For the sake of precise concepts, gliceryn is NOT an emulsifier. Emulsifiers contains a clear lipofilic and hidrofilic zones in the molecule. Which is an emulsifier is the partially reacted mono or di-glicerides, but in a crystal clear liquid there are not emulsions or dispersions. Glycerin is dissolved in the BD and separates from the liquid BD phase with time. - Original Message - From: Joe Street To: biofuel@sustainablelists.org Sent: Thursday, August 09, 2007 11:30 AM Subject: Re: [Biofuel] Glycerine Settling Time Tom; It makes sense. Glycerin is an emulsifier. Have you ever tried dosing the batch again with a little methoxide? After you remove the glycerin it doesn't take much to get the last bit of the reaction to go and settle out the remaining glycerin. Of course this is well known already. Kenji and many others do straight base catalysis as a two stage deal. You can do a methanol test of sorts and the unreacted oil will settle out. Then you can use the measured amount of unreacted oil in the methanol test vial to estimate the percentage unreacted oil in your batch and dose accordingly with the stoichiometric amount of methoxide. Assume neutral oil for this calculation. Rod and I do this regularly if the batch fails the QT and it works like a charm. Will save you settling time in the long run. Big skies Joe Thomas Kelly wrote: Joe, I took a sample from my latest batch of BD destined for my boiler (failed QT; but very little residue dropped out). It had settled for almost 10 hrs. That was yesterday morning. Today there is a small, but noticable, bit of glycerine on the bottom. More settled out after the initial 10 hrs of settling. I don't have any results with good BD to compare it with. If it turns out that glycerine settles out slower from incomplete vs complete reactions, it would answer the question I asked about getting emulsions when I washed low quality BD after letting it settle overnight, but not getting emulsions when it settled for a few days to a week. It would also help with a friendly disagreement I have with a friend. He seems to think that unreacted glycerides will settle out of the BD given time. He has taken to going with about 16% (vol/vol) of methanol in his batches. His logic: Unreacted oil causes emulsions, right? The emulsions I get in the first wash after settling the BD overnight are due to the unreacted oil? When I let it settle for a week or more I don't get emulsions, therefore the unreacted oil must have settled out. More likely: Some unreacted glycerides are still there, but after a week of settling more
Re: [Biofuel] Glycerine Settling Time
Hi Keith, Then if you do one-litre test batches first, especially with iffy batches of oil, Ops. I took Joe's point to be: If you have to re-process it is possible to use info from the QT to determine how much (how little) methanol you'll need to use. I think that both Joe and myself have standardize(d) the process so that passing the QT is the rule, not the exception. I run a QT towards the end of the reaction because I do not want to re-process. It takes me a few minutes and I like the certainty of knowing the BD is good before I pump it into my settling tank. If the test should fail when I'm making a batch for my car, I could use Joe's suggestion to help me better approximate the amount of methanol to add. If the process has been standardized, why bother? As you say: there shouldn't be any batches failing the QT. I've had a few failed batches in the past year. It seems to happen when I think I have it all figured out; standardized; can't fail. On one occasion the pump was making a bit of a funny noise when I came back to turn it off. Turned out a bit of paper towel or something had gotten into the impeller; inadequate agitation? Had I tested the BD before pumping it into the settling tank I could have avoided re-processing. While condensed water in bottom-of-the-barrel methanol or recovered methanol, contaminated caustic, etc may rear their ugly head in 1L test batches prior to running a batch, I think I would still run a QT prior to settling. Big skies :-) And broad horizons. Big lunch to you, I just had a garden pizza with Brocolli, zucchini, green peppers, sliced tomato, and chopped (v. mild) hot peppers. MMm Mm Tom - Original Message - From: Keith Addison [EMAIL PROTECTED] To: biofuel@sustainablelists.org Sent: Thursday, August 09, 2007 3:36 PM Subject: Re: [Biofuel] Glycerine Settling Time Hi Joe Tom; It makes sense. Glycerin is an emulsifier. Have you ever tried dosing the batch again with a little methoxide? After you remove the glycerin it doesn't take much to get the last bit of the reaction to go and settle out the remaining glycerin. Of course this is well known already. Kenji and many others do straight base catalysis as a two stage deal. You can do a methanol test of sorts and the unreacted oil will settle out. Then you can use the measured amount of unreacted oil in the methanol test vial to estimate the percentage unreacted oil in your batch and dose accordingly with the stoichiometric amount of methoxide. Assume neutral oil for this calculation. Rod and I do this regularly if the batch fails the QT and it works like a charm. Will save you settling time in the long run. Well, settling time is free. Acid-base aside, there's the two-stage base-base process, which quite a lot of people use and like, but otherwise why do more than one stage? Do you mean two separate stages, with a methanol test in between? So you process it twice? Plus extra methanol. Why not do it in a single phase? Todd Swearingen once suggested this here (discussing mixing pump sizes): To judge an appropriate reaction time, pull an exact amount of fluid (200 ml would suffice) out of the reaction stream every half-hour or hour after an arbitrary initial ~1 hour reaction period. Presuming that the contents of the reactor are kept homogenous from the pump flow, the volume of the glycerol cocktail that settles out of each sample will give you a fair gauge as to when your reaction completed. The suggestion would be to continue the reaction for ~1/2 hour beyond the point where your glyc cocktail volume stabilized. That works. Then, surely, you can standardise the process, with the only variable the amount of lye according to the titration level. Then if you do one-litre test batches first, especially with iffy batches of oil, and you have a clear idea of how your test-batch processing relates to your full-scale processing, life should be easier and there shouldn't be any batches failing the QT. What did I miss? Big skies :-) And broad horizons. Keith Joe Thomas Kelly wrote: Joe, I took a sample from my latest batch of BD destined for my boiler (failed QT; but very little residue dropped out). It had settled for almost 10 hrs. That was yesterday morning. Today there is a small, but noticable, bit of glycerine on the bottom. More settled out after the initial 10 hrs of settling. I don't have any results with good BD to compare it with. If it turns out that glycerine settles out slower from incomplete vs complete reactions, it would answer the question I asked about getting emulsions when I washed low quality BD after letting it settle overnight, but not getting emulsions when it settled for a few days to a week. It would also help with a friendly disagreement I have with a friend. He seems
