Re: [Biofuel] OFM Tube
Hello Andrew, John Quoting john owens [EMAIL PROTECTED]: hi I just finished designing and building a batch processor based on the journey to forever 90 ltr processor I now want to design an ofm flow tube. Is there any other sites other than cambridge That would be usefull. John I've thought about this, but think that the OFM technology might not be the best for yields. I know that the Cambridge site mentions biodiesel production but posts to this list make me think that the agitation may actually harm yield. I base this on a post I made and the subsequent replies I got when Mike Allen was designing Deep Throat, Aarghhh! Deep Thort! LOL! http://www.journeytoforever.org/biodiesel_processor8.html - I think it was during then, but anyway, someone was designing a reactor... The designer had mentioned that they where using a motor with a gear box so that the mixing blades rotate at a relatively slow speed hence not churning everything up. That's Michael's view, yes. There are 10 big paddles on that mixer though, slow speed's all that's needed, 100 rpm. I like that way of doing it with a mixer rather than high speeds with a couple of small paddles. I decided to use a pump instead with the JtF 90-litre processor, and Michael tut-tutted, all that agitation in the pump chamber, but it works very well anyway. Maybe it's different, slow agitation of the whole volume inside a tank or fast agitation of just a small part of the volume outside the tank with very little agitation inside the tank. I asked the question that wouldn't it be better to flog the crap out of it so that there was rapid and complete contact between all of the component chemicals. The reply was that due to the equilibrium (reaction kinematics???) of the oil/methoxide - biodiesel/glycerine reaction, it was better to do things slowly and allow the glycerine to drop out of the reation, down to the bottom of the reation, hence a tall slender reator is better that a low squat one. It appears that the presence of the glycerine will hinder the conversion from oil to BioD. We hadn't discussed it, but we both ended up with processors that drop out a lot of the glycerine during the process, both intentionally, but doing it in different ways. We have the idea that the level of the mixing tank outlet to the pump relative to the bottom of the tank is quite important. With our processor the mixing outlet is set somewhat higher than the level the glycerine by-product will settle at. That level will vary according to the oil (and process) you use. Especially with the rose at the inlet in the lid, there's not much agitation in the tank, mainly just circulation. The necessary agitation takes place inside the pump. The pump pulls the oil in from the tank outlet, but that's not very violent. As a result, a lot of the glycerine by-product settles out during the processing, which is a Good Thing. We think almost half of it settles out before the processing's finished. This does also remove some of the excess methanol, which is dissolved in the by-product. Aleks Kac's Foolproof two-stage acid-base process has an optional step of draining off some of the glycerine during the base stage. (The process runs fine without this step, he says. It's just a twitch to get higher yield if your processor has a bottom drain.) He said this about it: The process is running on the smallest sensible volume of alcohol. While removing a small portion of it with the by-product would seem to slow the reaction down, the rather large mass of removed by-product will tip the scale toward ester production. We find that's the case -- the settled out glycerine by-product more than offsets any methanol removed, with very satisfactory results. CAPTION: The sample on the left was taken from the top of the processor a couple of minutes before switching the pump off at the end of the process. Immediately after processing the whole batch is pumped into the holding tank via the processor's bottom drain. What comes out first is already-settled glycerine by-product. Pumped into the holding tank at the lid, it all gets mixed up again before settling. The sample on the right is of the same batch, taken from the top of the holding tank immediately after transfer -- twice as much glycerine by-product. -- Journey to Forever 90-litre processor http://journeytoforever.org/biodiesel_processor10.html The photograph is interesting. Best wishes Keith How is this relevant to OFM? With the OFM technology, all of the components are in the tube, hence the glycerine does not get a chance to drop out, in fact it is mixed up in the agitating components thus will probably hinder the reaction. I could see OFM being good for commercial situations where you could break the reaction down into, say, 3 parts/stages, the first part is run with the source oil but only a 1/3 of the required methoxide - and some glycerine is produced, but not enough to
Re: [Biofuel] OFM Tube
Quoting Keith Addison [EMAIL PROTECTED]: Hello Andrew, John Quoting john owens [EMAIL PROTECTED]: hi I just finished designing and building a batch processor based on the journey to forever 90 ltr processor I now want to design an ofm flow tube. Is there any other sites other than cambridge That would be usefull. John I've thought about this, but think that the OFM technology might not be the best for yields. I know that the Cambridge site mentions biodiesel production but posts to this list make me think that the agitation may actually harm yield. I base this on a post I made and the subsequent replies I got when Mike Allen was designing Deep Throat, Aarghhh! Deep Thort! LOL! I've just gone back to the page and had a look - I'm NOT EVEN GOING TO TRY and explain that Freudian slip!!! Andrew ___ 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] OFM Tube
Quoting Keith Addison [EMAIL PROTECTED]: Hello Andrew, John Quoting john owens [EMAIL PROTECTED]: hi I just finished designing and building a batch processor based on the journey to forever 90 ltr processor I now want to design an ofm flow tube. Is there any other sites other than cambridge That would be usefull. John I've thought about this, but think that the OFM technology might not be the best for yields. I know that the Cambridge site mentions biodiesel production but posts to this list make me think that the agitation may actually harm yield. I base this on a post I made and the subsequent replies I got when Mike Allen was designing Deep Throat, Aarghhh! Deep Thort! LOL! I've just gone back to the page and had a look - I'm NOT EVEN GOING TO TRY and explain that Freudian slip!!! Andrew ROFL!!! It would be superfluous anyway Andrew, I'm sure everyone can tell it's just that you spilled coffee on your keyboard and now it types all funny sometimes. On a respectable family-values list like this too, heavens, whatever next. Clearly it's all Michael's fault. Keith ___ 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] OFM Tube
Quoting john owens [EMAIL PROTECTED]: hi I just finished designing and building a batch processor based on the journey to forever 90 ltr processor I now want to design an ofm flow tube. Is there any other sites other than cambridge That would be usefull. John I've thought about this, but think that the OFM technology might not be the best for yields. I know that the Cambridge site mentions biodiesel production but posts to this list make me think that the agitation may actually harm yield. I base this on a post I made and the subsequent replies I got when Mike Allen was designing Deep Throat, http://www.journeytoforever.org/biodiesel_processor8.html - I think it was during then, but anyway, someone was designing a reactor... The designer had mentioned that they where using a motor with a gear box so that the mixing blades rotate at a relatively slow speed hence not churning everything up. I asked the question that wouldn't it be better to flog the crap out of it so that there was rapid and complete contact between all of the component chemicals. The reply was that due to the equilibrium (reaction kinematics???) of the oil/methoxide - biodiesel/glycerine reaction, it was better to do things slowly and allow the glycerine to drop out of the reation, down to the bottom of the reation, hence a tall slender reator is better that a low squat one. It appears that the presence of the glycerine will hinder the conversion from oil to BioD. How is this relevant to OFM? With the OFM technology, all of the components are in the tube, hence the glycerine does not get a chance to drop out, in fact it is mixed up in the agitating components thus will probably hinder the reaction. I could see OFM being good for commercial situations where you could break the reaction down into, say, 3 parts/stages, the first part is run with the source oil but only a 1/3 of the required methoxide - and some glycerine is produced, but not enough to hinder the reaction. The results of this are run through a centrifuge/settling tank with the glycerine being removed, then the oil with the next 1/3 of the methoxide added is run through the next section, more glycerine is produced, but once again not enough to hinder things, the results centrifuged and then the oil plus remaining methoxide run through the final stage, by now the original oil being fully converted and the resulting small amount of glycerine centrifuged off. This is probably a viable process for 100,000l/day plants but with centrifuges costing $10K each, probably not for the backyarder. Please bear in mind that this view of things is based on reading posts here, a bit of other research and being a Civil Engineer, not an organic chemist or Chemical Engineer. If I've misunderstood anything or got something wrong, please feel free to correct me. Regards, Andrew ___ 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/
