Hello Paul Some comments on this from Aleks Kac:
>Stick to the recipe. To the letter. Do not change, >simplify or speed up anything. There's two years >of trial and error research in this. > >It will take care of all sorts veg fats, even heavily used. >The "solid" portion must be reduced to less than 50% >because of the much lower acid stage temperature. >Animal fats content is best at less than 25% for pork >or chicken and less than 10% for bovine. These fats >at greater concentration should be processed base/base. Acid-base: http://journeytoforever.org/biodiesel_aleksnew.html Foolproof biodiesel process Base-base: http://journeytoforever.org/biodiesel_aleks.html Two-stage biodiesel process Best wishes Keith >----- Original Message ----- >From: "Appal Energy" <[EMAIL PROTECTED]> >[snip] > > And yes, the same percs apply for new oil, although perhaps to > > lesser degrees, depending upon the FFA content of the fresh oil. > > > > Todd Swearingen > > >Todd, what would you suggests as a reasonable cut off point for the home >brewer to decide between one step/base and acid/base? Someone else has >suggested 7g/L but I would think that is a bit high. > >One aspect of the acid/base method does not seem to have been given much >attention. >After the acid stage the reaction mix is still acidic. FFAs have been >reduced but the sulphuric acid is still present. This residual acid will >react with the NaOH added in the base stage and give an incomplete reaction >unless it is accounted for. >So I would suggest a titration before the base stage, taking into account >the dilution effect of the initial dose of alcohol on the oil. >If more than the recommended ammount of conc sulphuric acid has been used >(to push the reaction by binding the water produced) compensating for the >acidity becomes very important. >My first efforts at acid/base produced an incomplete reaction, which led me >to the above. >On a batch of WVO titrating at 16ml the single stage base method gave a raw >60% volume yield. The BD solidified and had to be liquified before it could >be washed. Acid/base method of the same oil gave a raw volume yield of 105% >when the titration ammount of NaOH was used in the second stage. The BD from >the acid/base method was liquid. > >Regards, > >Paul Gobert. ------------------------ Yahoo! Groups Sponsor ---------------------~--> Free $5 Love Reading Risk Free! http://us.click.yahoo.com/3PCXaC/PfREAA/Ey.GAA/FGYolB/TM ---------------------------------------------------------------------~-> Biofuel at Journey to Forever: http://journeytoforever.org/biofuel.html Biofuels list archives: http://archive.nnytech.net/ Please do NOT send "unsubscribe" messages to the list address. To unsubscribe, send an email to: [EMAIL PROTECTED] Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
