Re: [biofuels-biz] Re: hi ffa feed stocks
Why not just drain off the small amount of glycerine (will also contain some water) from the bottom of the esterification reaction and decant the excess alcohol off the top (which will be slightly glycerin stained and also contain some water)? After doing so, you'll find that the transesterification can take place with as little as 1-1.5 grams of sodium or potassium catalyst if given enough alcohol and time. No need to boil between acid and base stages. Todd Swearingen - Original Message - From: David Teal [EMAIL PROTECTED] To: biofuels-biz@yahoogroups.com Sent: Friday, September 06, 2002 4:44 PM Subject: Re: [biofuels-biz] Re: hi ffa feed stocks One fact in common to all the recent contributors to this thread has been the bad effects of water produced in the acid esterification of FFAs; including saponification in the subsequent base transestrification stage. Most of us like to keep things simple, so I contemplate a boiling operation between acid and basic stages to evaporate the unwanted water. This would apply to our Scottish lard chip fat supply. The energy burden need not be too onerous using heat exchangers to recover some of the sensible heat (latent heat can't be easily recovered), and by using glycerol as heating fuel. I am a little worried about what boiling sulphuric acid (albeit dilute at this stage) will do to ordinary piping and vessel materials. David T. Yahoo! Groups Sponsor -~-- 4 DVDs Free +sp Join Now http://us.click.yahoo.com/pt6YBB/NXiEAA/MVfIAA/9bTolB/TM --- --~- Biofuels at Journey to Forever http://journeytoforever.org/biofuel.html Biofuel at WebConX http://www.webconx.dns2go.com/2000/biofuel/biofuel.htm List messages are archived at the Info-Archive at NNYTech: http://archive.nnytech.net/ To unsubscribe from this group, send an email to: [EMAIL PROTECTED] Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/ Yahoo! Groups Sponsor -~-- 4 DVDs Free +sp Join Now http://us.click.yahoo.com/pt6YBB/NXiEAA/MVfIAA/9bTolB/TM -~- Biofuels at Journey to Forever http://journeytoforever.org/biofuel.html Biofuel at WebConX http://www.webconx.dns2go.com/2000/biofuel/biofuel.htm List messages are archived at the Info-Archive at NNYTech: http://archive.nnytech.net/ To unsubscribe from this group, send an email to: [EMAIL PROTECTED] Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
Re: [biofuels-biz] Re: hi ffa feed stocks
One fact in common to all the recent contributors to this thread has been the bad effects of water produced in the acid esterification of FFAs; including saponification in the subsequent base transestrification stage. Most of us like to keep things simple, so I contemplate a boiling operation between acid and basic stages to evaporate the unwanted water. This would apply to our Scottish lard chip fat supply. The energy burden need not be too onerous using heat exchangers to recover some of the sensible heat (latent heat can't be easily recovered), and by using glycerol as heating fuel. I am a little worried about what boiling sulphuric acid (albeit dilute at this stage) will do to ordinary piping and vessel materials. David T. Yahoo! Groups Sponsor -~-- 4 DVDs Free +sp Join Now http://us.click.yahoo.com/pt6YBB/NXiEAA/MVfIAA/9bTolB/TM -~- Biofuels at Journey to Forever http://journeytoforever.org/biofuel.html Biofuel at WebConX http://www.webconx.dns2go.com/2000/biofuel/biofuel.htm List messages are archived at the Info-Archive at NNYTech: http://archive.nnytech.net/ To unsubscribe from this group, send an email to: [EMAIL PROTECTED] Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
Re: [biofuels-biz] Re: hi ffa feed stocks
Dear Keith, Actually I did understand this, having checked it out a bit and discussed it with a few people, but I understand it even better now - thanks! What puzzled me and mainly why I asked was what you said about methanol excesses. For the whole process, Aleks uses rather less methanol than you'd probably have to use for high-ffa feedstock by most other methods, especially single-stage base. Overall methanol use, not just for the esterification first stage, is about 67% excess, depending on the oil; your 9 to 12 times applies to the first stage only. Well, that's all clear now. Sorry if I mislead you in any way. By the way, there are tables showing the stoichiometric ratios for different oils here: http://journeytoforever.org/biodiesel_meth.html How much methanol? Re the condenser, that's one way, but it's hard to separate the glycerine/FFAs/catalyst in the glycerine layer with the methanol already removed. Maybe a better way is to drain off the glycerine layer first, then evaporate off the excess methanol in the biodiesel (it's about half-half in the biodiesel and the glycerine layer). We do indeed drain the glycerol from the biodiesel in the reactor and we have even tried doing this while the reaction is proceeeding as suggested by Aleks. Theoretically, the removal of a product should push the reaction to produce more product (Le Chatelier's Principle) but we have not yet measured any benefits. After separating the glycerine layer (http://journeytoforever.org/biodiesel_glycsep.html), the rest of the excess methanol can be recovered from the purified glycerine (somewhat purified glycerine). At present, we are setting the glycerol in trays and using it as a soap and general grease remover around the workshop. However . . . . one day . . . I'd appreciate a picture and diagrams, if that's not too much trouble, thanks. Our Internet link is really running slowly at present with many disconnections. I will try over the weekend when traffic is less. So you are using the acid-base process as your main method, with both the 100-l and the 1-tonne reactors? No. The 1 tonne reactor continues to use the base-catalysed transesterification of molten stearine/palmitin. The FFA of this feedstock is quite low (less than 1%). We are exploring the acid-base process with HiFFA feedstocks in the smaller reactor and in the laboratory. We know that the process of refining the crude palm oil reduces the FFA to 0.5% by a process of saponification using an almost stoichiometric amount of sodium hydroxide dissolved in water. But the resultant soap is largely a waste material. Some of our crude palm oil comes in at 10%FFA and the saponification process produces rather a lot of greasy soap from such a feedstock. Even the palm-oil refiners don't like this stuff (which is, of course, why it easily procurable!) By adjusting the temperature, we can remove this soap from the bottom of the saponification reactor rather than skimming it off the top but we still lose too much oil to make it an attractive option. Using Alek's acid-base process on such a feedstock has the potential to replace this useless soap with methyl ester. But it appears that any ester actually formed with the acid catalyst is subsequently broken down and saponified along with the palm oil in the base-catalysed second reaction. The result is a spongy mass of soap which is hard to separate from any methyl ester which may have been formed. The main culprit is, I believe, the water which was formed in the saponification process. (But I could be wrong) We haven't given up entirely on the 10% FFA feedstock but we are going to concentrate our immediate research on the more usual and widely available 5% FFA crude palm oil. Some people have been having trouble using it with crude palm oil (high FFA and high percentage of stearin), but not with olein palm oil. We are some people!! But we find that olein goes like a dream! We have even put together a simple powered-roller reactor which mixes the methoxide with the olein at ambient temperature (30 degC) and takes less than 15 minutes to form the ester. You can even shake them together manually. But we haven't tried olein with HiFFA (yet). Any ideas would be welcome Regards Michael Allen __ Do You Yahoo!? Yahoo! Finance - Get real-time stock quotes http://finance.yahoo.com Yahoo! Groups Sponsor -~-- 4 DVDs Free +sp Join Now http://us.click.yahoo.com/pt6YBB/NXiEAA/MVfIAA/9bTolB/TM -~- Biofuels at Journey to Forever http://journeytoforever.org/biofuel.html Biofuel at WebConX http://www.webconx.dns2go.com/2000/biofuel/biofuel.htm List messages are archived at the Info-Archive at NNYTech: http://archive.nnytech.net/ To unsubscribe from this group, send an email to: [EMAIL
Re: [biofuels-biz] Re: hi ffa feed stocks
Dear Keith, Actually I did understand this, having checked it out a bit and discussed it with a few people, but I understand it even better now - thanks! What puzzled me and mainly why I asked was what you said about methanol excesses. For the whole process, Aleks uses rather less methanol than you'd probably have to use for high-ffa feedstock by most other methods, especially single-stage base. Overall methanol use, not just for the esterification first stage, is about 67% excess, depending on the oil; your 9 to 12 times applies to the first stage only. Well, that's all clear now. Sorry if I mislead you in any way. By the way, there are tables showing the stoichiometric ratios for different oils here: http://journeytoforever.org/biodiesel_meth.html How much methanol? Re the condenser, that's one way, but it's hard to separate the glycerine/FFAs/catalyst in the glycerine layer with the methanol already removed. Maybe a better way is to drain off the glycerine layer first, then evaporate off the excess methanol in the biodiesel (it's about half-half in the biodiesel and the glycerine layer). We do indeed drain the glycerol from the biodiesel in the reactor and we have even tried doing this while the reaction is proceeeding as suggested by Aleks. Theoretically, the removal of a product should push the reaction to produce more product (Le Chatelier's Principle) but we have not yet measured any benefits. After separating the glycerine layer (http://journeytoforever.org/biodiesel_glycsep.html), the rest of the excess methanol can be recovered from the purified glycerine (somewhat purified glycerine). At present, we are setting the glycerol in trays and using it as a soap and general grease remover around the workshop. However . . . . one day . . . I'd appreciate a picture and diagrams, if that's not too much trouble, thanks. Our Internet link is really running slowly at present with many disconnections. I will try over the weekend when traffic is less. So you are using the acid-base process as your main method, with both the 100-l and the 1-tonne reactors? No. The 1 tonne reactor continues to use the base-catalysed transesterification of molten stearine/palmitin. The FFA of this feedstock is quite low (less than 1%). We are exploring the acid-base process with HiFFA feedstocks in the smaller reactor and in the laboratory. We know that the process of refining the crude palm oil reduces the FFA to 0.5% by a process of saponification using an almost stoichiometric amount of sodium hydroxide dissolved in water. But the resultant soap is largely a waste material. Some of our crude palm oil comes in at 10%FFA and the saponification process produces rather a lot of greasy soap from such a feedstock. Even the palm-oil refiners don't like this stuff (which is, of course, why it easily procurable!) By adjusting the temperature, we can remove this soap from the bottom of the saponification reactor rather than skimming it off the top but we still lose too much oil to make it an attractive option. Using Alek's acid-base process on such a feedstock has the potential to replace this useless soap with methyl ester. But it appears that any ester actually formed with the acid catalyst is subsequently broken down and saponified along with the palm oil in the base-catalysed second reaction. The result is a spongy mass of soap which is hard to separate from any methyl ester which may have been formed. The main culprit is, I believe, the water which was formed in the saponification process. (But I could be wrong) We haven't given up entirely on the 10% FFA feedstock but we are going to concentrate our immediate research on the more usual and widely available 5% FFA crude palm oil. Some people have been having trouble using it with crude palm oil (high FFA and high percentage of stearin), but not with olein palm oil. We are some people!! But we find that olein goes like a dream! We have even put together a simple powered-roller reactor which mixes the methoxide with the olein at ambient temperature (30 degC) and takes less than 15 minutes to form the ester. But we haven't tried olein with HiFFA (yet). Any ideas would be welcome Regards Michael Allen __ Do You Yahoo!? Yahoo! Finance - Get real-time stock quotes http://finance.yahoo.com Yahoo! Groups Sponsor -~-- 4 DVDs Free +sp Join Now http://us.click.yahoo.com/pt6YBB/NXiEAA/MVfIAA/9bTolB/TM -~- Biofuels at Journey to Forever http://journeytoforever.org/biofuel.html Biofuel at WebConX http://www.webconx.dns2go.com/2000/biofuel/biofuel.htm List messages are archived at the Info-Archive at NNYTech: http://archive.nnytech.net/ To unsubscribe from this group, send an email to: [EMAIL PROTECTED] Your use of Yahoo! Groups is
Re: [biofuels-biz] Re: hi ffa feed stocks
Hi Michael (Sorry to be a tad pedantic and maybe a bit long-winded but it sort of goes with the patch as a Visiting Professor here in Thailand!) Not at all, not long-winded, nice clear explanation, I'm sure a lot of people will appreciate that. Actually I did understand this, having checked it out a bit and discussed it with a few people, but I understand it even better now - thanks! What puzzled me and mainly why I asked was what you said about methanol excesses. For the whole process, Aleks uses rather less methanol than you'd probably have to use for high-ffa feedstock by most other methods, especially single-stage base. Overall methanol use, not just for the esterification first stage, is about 67% excess, depending on the oil; your 9 to 12 times applies to the first stage only. Well, that's all clear now. By the way, there are tables showing the stoichiometric ratios for different oils here: http://journeytoforever.org/biodiesel_meth.html How much methanol? Re the condenser, that's one way, but it's hard to separate the glycerine/FFAs/catalyst in the glycerine layer with the methanol already removed. Maybe a better way is to drain off the glycerine layer first, then evaporate off the excess methanol in the biodiesel (it's about half-half in the biodiesel and the glycerine layer). After separating the glycerine layer (http://journeytoforever.org/biodiesel_glycsep.html), the rest of the excess methanol can be recovered from the purified glycerine (somewhat purified glycerine). I'd appreciate a picture and diagrams, if that's not too much trouble, thanks. So you are using the acid-base process as your main method, with both the 100-l and the 1-tonne reactors? Some people have been having trouble using it with crude palm oil (high FFA and high percentage of stearin), but not with olein palm oil. Thanks again, best wishes Keith Hi Keith, In answer to your question: Lets start with a litre of oil. Ours has a density of 910.9 grams/litre so a Free Fatty Acid content of 5% on a weight basis means that 5% of that 910.9 grams is FFA So one litre of oil with a FFA content of 5% (weight basis) contains 45.55 gms of FFA The chemical reaction of esterification is H+ R-COOH + CH3OH = CH3-OOC-R + H2O In other words, 1 molecule of acid reacts with one molecule of alcohol to give one molecule of ester plus one molecule of water . Using the molecular weights and choosing palmitic acid as the predominant fatty acid, we get that 256.42 grams of palmitic acid needs 32.04 grams of methanol to produce 18 grams of water and 270.5 grams of methyl palmitate. so 45.55 grams will need 32.04 x 45.55/256.42 = 5.69 grams of methanol Taking 791 grams/litre as the density of methanol, this means that we need to have a minimum 5.69/791 litres of methanol available for the reaction to go to completion. This is only 0.007 litres! So why do we add 0.08 litres of methanol per litre of oil as set out in First stage para 4 of Aleksander Kac's http://journeytoforever.org/biodiesel_aleksnew.html? Well the = sign in the above equation is to show that it is reversible. That is, if we take the ester and add some water in the presence of a strong acid, we get some free fatty acid formed and some alcohol. (This method is actually used in the analysis of unknown fats and oils ) The main reason we add excess methanol (about ten times as much as the stoichiometric amount needed) is to force the reaction further in the direction we want it go. Removing the water has the same effect so using concentrated sulfuric acid as the catalyst also helps the reaction move over to the right because it is really great at dehydrating things like sugar and human flesh . . . . . . . . :-( But, as I suggested in my note, the excess methanol also dilutes whatever water is left at the end of the esterification reaction. (And we are going to need that methanol for the transesterification stage anyway). When we neutralise that sulfuric acid with sodium hydroxide, we make sodium sulfate which does not bond to water quite as strongly as the sulfuric acid so, as a consequence, I suspect that the water activity probably increases. Incidentally, you can make the same calculation for any fatty acid found in vegetable or animal oils and you will find that between 9 and 12 times the minimum stoichiometric amount of methanol is used in the Aleksander Kac esterification process. For similar reasons, the transesterification process also uses excess methanol: 0.2 litres of methanol/litre of oil is about 1.7 times the stoichiometric amount needed and 0.25 litres of methanol/litre of oil is about twice the minimum amount needed. (Aleksander Kac's two methods). You get slightly different results if you cover all the possible mono-glycerides, di-glycerides, tri-glycerides of all the fatty acids but the above figures are quoted for glyceryl tri-palmitate which is one of the major components in our oil feedstock. This is
Re: [biofuels-biz] Re: hi ffa feed stocks
Hi Keith, In answer to your question: Lets start with a litre of oil. Ours has a density of 910.9 grams/litre so a Free Fatty Acid content of 5% on a weight basis means that 5% of that 910.9 grams is FFA So one litre of oil with a FFA content of 5% (weight basis) contains 45.55 gms of FFA The chemical reaction of esterification is H+ R-COOH + CH3OH = CH3-OOC-R + H2O In other words, 1 molecule of acid reacts with one molecule of alcohol to give one molecule of ester plus one molecule of water . Using the molecular weights and choosing palmitic acid as the predominant fatty acid, we get that 256.42 grams of palmitic acid needs 32.04 grams of methanol to produce 18 grams of water and 270.5 grams of methyl palmitate. so 45.55 grams will need 32.04 x 45.55/256.42 = 5.69 grams of methanol Taking 791 grams/litre as the density of methanol, this means that we need to have a minimum 5.69/791 litres of methanol available for the reaction to go to completion. This is only 0.007 litres! So why do we add 0.08 litres of methanol per litre of oil as set out in First stage para 4 of Aleksander Kac's http://journeytoforever.org/biodiesel_aleksnew.html? Well the = sign in the above equation is to show that it is reversible. That is, if we take the ester and add some water in the presence of a strong acid, we get some free fatty acid formed and some alcohol. (This method is actually used in the analysis of unknown fats and oils ) The main reason we add excess methanol (about ten times as much as the stoichiometric amount needed) is to force the reaction further in the direction we want it go. Removing the water has the same effect so using concentrated sulfuric acid as the catalyst also helps the reaction move over to the right because it is really great at dehydrating things like sugar and human flesh . . . . . . . . :-( But, as I suggested in my note, the excess methanol also dilutes whatever water is left at the end of the esterification reaction. (And we are going to need that methanol for the transesterification stage anyway). When we neutralise that sulfuric acid with sodium hydroxide, we make sodium sulfate which does not bond to water quite as strongly as the sulfuric acid so, as a consequence, I suspect that the water activity probably increases. Incidentally, you can make the same calculation for any fatty acid found in vegetable or animal oils and you will find that between 9 and 12 times the minimum stoichiometric amount of methanol is used in the Aleksander Kac esterification process. For similar reasons, the transesterification process also uses excess methanol: 0.2 litres of methanol/litre of oil is about 1.7 times the stoichiometric amount needed and 0.25 litres of methanol/litre of oil is about twice the minimum amount needed. (Aleksander Kac's two methods). You get slightly different results if you cover all the possible mono-glycerides, di-glycerides, tri-glycerides of all the fatty acids but the above figures are quoted for glyceryl tri-palmitate which is one of the major components in our oil feedstock. This is why I feel that a condenser on the outlet of the reactor is a useful way of saving money. And because chemical reactions go faster at higher temperatures, we can carry out the reaction at a temperature closer to the boiling point of methanol (64.6C) by refluxing all the condensed methanol back into the reactor until the reaction is finished. At present we use a simple copper-pipe heat exchanger and we totally recycle the cooling water through two x 200 litre oil drums working as an evaporative cooler by having a sprinkler over three perforated baking trays. (I'll send you a picture and some plans if you like.) We have assessed the advantages of a condenser with our 100 litre reactor and, as a result, we our currently modifying the 1 tonne reactor used for making biodiesel from stearin. (This 1 tonne unit is the reactor which produces biodiesel for the railway trials) (Sorry to be a tad pedantic and maybe a bit long-winded but it sort of goes with the patch as a Visiting Professor here in Thailand!) Best wishes Michael Allen --- Keith Addison [EMAIL PROTECTED] wrote: Hello Michael snip Incidentally, with respect to the high free fatty acid feeds, the limit to the amount of FFA possible is probably related to the formation of water in Alek's first stage esterification using sulfuric acid as the catalyst. Thus 5%FFA in the oil means that 4mls of water are produced for every litre of oil. This water increases soap formation in the second stage (which is catalysed by sodium hydroxide). I know about the water, that'd be about right. But I don't know about this: Alek Kak's method (http://journeytoforever.org/biodiesel_aleksnew.html) reduces this impact by using 95% pure sulfuric acid which has a strong affinity for water. He also recommends about 9 times the amount of methanol theoretically needed to react with the FFA. This
Re: [biofuels-biz] Re: hi ffa feed stocks
Dear Marco, I presume that you have read the http://journeytoforever.org/biodiesel_svo.html and their stuff on ethanol? It is an excellent place to start and concisely sets out all the major constraints. Our work with agricultural engines showed that there is a considerable difference between the injection ports of small agricultural diesels so it might be a bit dangerous to generalise. Essentially though, we recommend starting and stopping on petro-diesel (or biodiesel if available). The exhaust pipe for the engine is taken out through a simple one-pass heat exchanger in the palm-oil fuel tank. After about 5 mins running on petro-diesel, the 40 litres of palm oil is warm enough to have similar flow properties as petro-diesel. So we turn off one fuel supply and move to the other. We also recommend running the engine on petro-diesel for the last five minutes of operation too. That way, everything is left free of fatty-acid residues which might cause corrosion (particularly if the engine is not going to be used for a while.) Ambient temperatures here rarely fall below 27C or rise above 34C. As a consequence, SPO is always liquid. This means that with some engines, you can actually start them on palm-oil. But we don't recommend it. Where are you precisely? What sort of engines do you want to use SPO with? What operations do you want the engines to perform (electricity generation, pumping, transport, ploughing etc.). What are your ambient temperatures? I have some experience of using ethanol/methanol blends with petroleum for spark-ignition engines. We did this work in New Zealand about twenty years ago and the results are well documented. However these are highly volatile fuels with low-flash points and are nothing like palm-oil really. Regards Michael --- marcohgcardoso [EMAIL PROTECTED] wrote: Dear Michael, tks a lot for your help. So, we can use palm oil direct without transes.? WHich motor modifications do you usually do? Do you know how to do the sme process with Ethanol? Or anyone who does it? regards, Marco --- In [EMAIL PROTECTED], Michael Allen [EMAIL PROTECTED] wrote: Dear Marco, I have plent of Palm Oil. When you mentioned that you used Straight Palm Oil you hadn't transerterificate the oil? That is correct. The first stage of our program was to demonstrate that oil-palm growers could run their farm machinery on straight palm oil (SPO)by making simple engine modifications. The overall aim of the program is to stabilise oil prices for oil-palm growers. That means that we are looking at all aspects of palm-oil use. Incidentally, with respect to the high free fatty acid feeds, the limit to the amount of FFA possible is probably related to the formation of water in Alek's first stage esterification using sulfuric acid as the catalyst. Thus 5%FFA in the oil means that 4mls of water are produced for every litre of oil. This water increases soap formation in the second stage (which is catalysed by sodium hydroxide). Alek Kak's method (http://journeytoforever.org/biodiesel_aleksnew.html) reduces this impact by using 95% pure sulfuric acid which has a strong affinity for water. He also recommends about 9 times the amount of methanol theoretically needed to react with the FFA. This also has the effect of reducing the water concentration. So, for high(er) FFA, more methanol and more sulfuric acid should be beneficial. However, that means more sodium hydroxide to neutralise the acid and some form of methanol recovery system. We use a simple condenser connected to the reactor to grab the methanol. We can either recycle this to the next batch or operate the reactor under total reflux. This makes it possible to operate the reactor at a higher temperature and so accelerate the rate of the separate reactions. Hope this gives you some useful ideas Regards Michael Allen --- In [EMAIL PROTECTED], Michael Allen [EMAIL PROTECTED] wrote: Dear David, We did extensive work last year on heated Straight Palm Oil (SPO) in two-wheeled tractors and fishing boat motors. We had field trials by local farmers of four commercial tractors and did test-bed work with three others. Crude palm oil caused erosion of the pistons by late ignition but refined palm-oil (of the grade used for cooking oil) worked well. But we never got around to using it in a locomotive. This year we have been trying a range of reactor designs to optimise methyl ester production from refined oil. We are now moving back through various forms of oil refinement towards the crude palm oil (CPO). And yes, we are currently using the Aleks Kak two-stage process. And yes it is currently at atmospheric pressure (although the reactor was designed to handle 200 kPa mainly as a safety
Re: [biofuels-biz] Re: hi ffa feed stocks
Hello Michael snip Incidentally, with respect to the high free fatty acid feeds, the limit to the amount of FFA possible is probably related to the formation of water in Alek's first stage esterification using sulfuric acid as the catalyst. Thus 5%FFA in the oil means that 4mls of water are produced for every litre of oil. This water increases soap formation in the second stage (which is catalysed by sodium hydroxide). I know about the water, that'd be about right. But I don't know about this: Alek Kak's method (http://journeytoforever.org/biodiesel_aleksnew.html) reduces this impact by using 95% pure sulfuric acid which has a strong affinity for water. He also recommends about 9 times the amount of methanol theoretically needed to react with the FFA. This also has the effect of reducing the water concentration. It uses 8% methanol v/v oil for the acid stage, and 12% for the second stage. You're saying acid esterification of 5% FFAs needs less than 1% methanol? So, for high(er) FFA, more methanol and more sulfuric acid should be beneficial. However, that means more sodium hydroxide to neutralise the acid and some form of methanol recovery system. We use a simple condenser connected to the reactor to grab the methanol. We can either recycle this to the next batch or operate the reactor under total reflux. This makes it possible to operate the reactor at a higher temperature and so accelerate the rate of the separate reactions. You're using Aleks's acid-base method this way? Or is that the one-stage transesterification you mentioned previously, for the train's B50? Best Keith Hope this gives you some useful ideas Regards Michael Allen --- In [EMAIL PROTECTED], Michael Allen [EMAIL PROTECTED] wrote: Dear David, We did extensive work last year on heated Straight Palm Oil (SPO) in two-wheeled tractors and fishing boat motors. We had field trials by local farmers of four commercial tractors and did test-bed work with three others. Crude palm oil caused erosion of the pistons by late ignition but refined palm-oil (of the grade used for cooking oil) worked well. But we never got around to using it in a locomotive. This year we have been trying a range of reactor designs to optimise methyl ester production from refined oil. We are now moving back through various forms of oil refinement towards the crude palm oil (CPO). And yes, we are currently using the Aleks Kak two-stage process. And yes it is currently at atmospheric pressure (although the reactor was designed to handle 200 kPa mainly as a safety feature. Even so, some enthusiastic welders have overpressurised it twice now through forgetting to flood (and then drain) it with water before modifying the unit). The locomotive I mentioned is running on a B50 blend: It uses esters from a one stage trans-esterification reaction of methanol with the stearin and palmitin which has separated from the CPO. This waxy stuff is probably quite comparable with the good Scottish lard. Lots of luck! Michael Allen --- Keith Addison [EMAIL PROTECTED] wrote: Thanks for your response, prof. Allen. I'll formulate an inquiry to Mohammed Farid as you suggest. You mentioned Thai railway application. I saw somewhere that German railways are using SVO in some of their shunting engines. http://www.wired.com/news/technology/0,1282,53591,00.html Choo-Choo Trains on Energy Crunch The encouraging part of your message is you are reacting at 60C and that this is near methanol boiling point. That implies you are succeeding at atmospheric pressure. Do you use conc. sulphuric acid first stage? I agree meth recovery is so simple that using excess is not really a problem. David T. Yahoo! Groups Sponsor -~-- 4 DVDs Free +sp Join Now http://us.click.yahoo.com/pt6YBB/NXiEAA/MVfIAA/9bTolB/TM -~- Biofuels at Journey to Forever http://journeytoforever.org/biofuel.html Biofuel at WebConX http://www.webconx.dns2go.com/2000/biofuel/biofuel.htm List messages are archived at the Info-Archive at NNYTech: http://archive.nnytech.net/ To unsubscribe from this group, send an email to: [EMAIL PROTECTED] Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
Re: [biofuels-biz] Re: hi ffa feed stocks
Dear Marco, I have plent of Palm Oil. When you mentioned that you used Straight Palm Oil you hadn't transerterificate the oil? That is correct. The first stage of our program was to demonstrate that oil-palm growers could run their farm machinery on straight palm oil (SPO)by making simple engine modifications. The overall aim of the program is to stabilise oil prices for oil-palm growers. That means that we are looking at all aspects of palm-oil use. Incidentally, with respect to the high free fatty acid feeds, the limit to the amount of FFA possible is probably related to the formation of water in Alek's first stage esterification using sulfuric acid as the catalyst. Thus 5%FFA in the oil means that 4mls of water are produced for every litre of oil. This water increases soap formation in the second stage (which is catalysed by sodium hydroxide). Alek Kak's method (http://journeytoforever.org/biodiesel_aleksnew.html) reduces this impact by using 95% pure sulfuric acid which has a strong affinity for water. He also recommends about 9 times the amount of methanol theoretically needed to react with the FFA. This also has the effect of reducing the water concentration. So, for high(er) FFA, more methanol and more sulfuric acid should be beneficial. However, that means more sodium hydroxide to neutralise the acid and some form of methanol recovery system. We use a simple condenser connected to the reactor to grab the methanol. We can either recycle this to the next batch or operate the reactor under total reflux. This makes it possible to operate the reactor at a higher temperature and so accelerate the rate of the separate reactions. Hope this gives you some useful ideas Regards Michael Allen --- In [EMAIL PROTECTED], Michael Allen [EMAIL PROTECTED] wrote: Dear David, We did extensive work last year on heated Straight Palm Oil (SPO) in two-wheeled tractors and fishing boat motors. We had field trials by local farmers of four commercial tractors and did test-bed work with three others. Crude palm oil caused erosion of the pistons by late ignition but refined palm-oil (of the grade used for cooking oil) worked well. But we never got around to using it in a locomotive. This year we have been trying a range of reactor designs to optimise methyl ester production from refined oil. We are now moving back through various forms of oil refinement towards the crude palm oil (CPO). And yes, we are currently using the Aleks Kak two-stage process. And yes it is currently at atmospheric pressure (although the reactor was designed to handle 200 kPa mainly as a safety feature. Even so, some enthusiastic welders have overpressurised it twice now through forgetting to flood (and then drain) it with water before modifying the unit). The locomotive I mentioned is running on a B50 blend: It uses esters from a one stage trans-esterification reaction of methanol with the stearin and palmitin which has separated from the CPO. This waxy stuff is probably quite comparable with the good Scottish lard. Lots of luck! Michael Allen --- Keith Addison [EMAIL PROTECTED] wrote: Thanks for your response, prof. Allen. I'll formulate an inquiry to Mohammed Farid as you suggest. You mentioned Thai railway application. I saw somewhere that German railways are using SVO in some of their shunting engines. http://www.wired.com/news/technology/0,1282,53591,00.html Choo-Choo Trains on Energy Crunch The encouraging part of your message is you are reacting at 60C and that this is near methanol boiling point. That implies you are succeeding at atmospheric pressure. Do you use conc. sulphuric acid first stage? I agree meth recovery is so simple that using excess is not really a problem. David T. __ Do You Yahoo!? Yahoo! Finance - Get real-time stock quotes http://finance.yahoo.com __ Do You Yahoo!? Yahoo! Finance - Get real-time stock quotes http://finance.yahoo.com Yahoo! Groups Sponsor -~-- 4 DVDs Free +sp Join Now http://us.click.yahoo.com/pt6YBB/NXiEAA/MVfIAA/9bTolB/TM -~- Biofuels at Journey to Forever http://journeytoforever.org/biofuel.html Biofuel at WebConX http://www.webconx.dns2go.com/2000/biofuel/biofuel.htm List messages are archived at the Info-Archive at NNYTech: http://archive.nnytech.net/ To unsubscribe from this group, send an email to: [EMAIL PROTECTED] Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
Re: [biofuels-biz] Re: hi ffa feed stocks
Dear David, We did extensive work last year on heated Straight Palm Oil (SPO) in two-wheeled tractors and fishing boat motors. We had field trials by local farmers of four commercial tractors and did test-bed work with three others. Crude palm oil caused erosion of the pistons by late ignition but refined palm-oil (of the grade used for cooking oil) worked well. But we never got around to using it in a locomotive. This year we have been trying a range of reactor designs to optimise methyl ester production from refined oil. We are now moving back through various forms of oil refinement towards the crude palm oil (CPO). And yes, we are currently using the Aleks Kak two-stage process. And yes it is currently at atmospheric pressure (although the reactor was designed to handle 200 kPa mainly as a safety feature. Even so, some enthusiastic welders have overpressurised it twice now through forgetting to flood (and then drain) it with water before modifying the unit). The locomotive I mentioned is running on a B50 blend: It uses esters from a one stage trans-esterification reaction of methanol with the stearin and palmitin which has separated from the CPO. This waxy stuff is probably quite comparable with the good Scottish lard. Lots of luck! Michael Allen --- Keith Addison [EMAIL PROTECTED] wrote: Thanks for your response, prof. Allen. I'll formulate an inquiry to Mohammed Farid as you suggest. You mentioned Thai railway application. I saw somewhere that German railways are using SVO in some of their shunting engines. http://www.wired.com/news/technology/0,1282,53591,00.html Choo-Choo Trains on Energy Crunch The encouraging part of your message is you are reacting at 60C and that this is near methanol boiling point. That implies you are succeeding at atmospheric pressure. Do you use conc. sulphuric acid first stage? I agree meth recovery is so simple that using excess is not really a problem. David T. __ Do You Yahoo!? Yahoo! Finance - Get real-time stock quotes http://finance.yahoo.com Yahoo! Groups Sponsor -~-- 4 DVDs Free +sp Join Now http://us.click.yahoo.com/pt6YBB/NXiEAA/mG3HAA/9bTolB/TM -~- Biofuels at Journey to Forever http://journeytoforever.org/biofuel.html Biofuel at WebConX http://www.webconx.dns2go.com/2000/biofuel/biofuel.htm List messages are archived at the Info-Archive at NNYTech: http://archive.nnytech.net/ To unsubscribe from this group, send an email to: [EMAIL PROTECTED] Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
Re: [biofuels-biz] Re: hi ffa feed stocks
Hi David, [EMAIL PROTECTED] is running a research project on transesterification of beef tallow. I'm not sure he has heaps of results from his enzymatic process yet but he certainly has references to all the literature you need. (Mohammed is an Associate Professor of Chemical Engineering at the University of Auckland in New Zealand) We are making commercial quantities (1 tonne/day)of biodiesel by transesterifying stearin from palm oil. Indeed, one of the Thai railways routes from Hadyai to Sungei Golok is using a B50 blend of our stuff with petro diesel in their 150km run every day. At the moment I have built a 120 litre deep bed unit for working on a crude palm oil feedstock with the methoxide introduced at the bottom. We have lots of stearin and palmitin (lard!) floating in the olein liquid (and large amounts of free fatty acids) so we have to run the reactor at 60C. This temperature is close enough to the boiling point of methanol that we have to recover the excess methanol to make the process economic. I imagine you would have to do the same with lard. Lots of luck Michael Allen Visiting Professor Prince of Songkla University Thailand --- David Teal [EMAIL PROTECTED] wrote: In Scotland, chip shops use lard (animal fat). Last week I took a quantity of such material and tried (admittedly without much confidence) using the same procedure as for WVO (2 stage base). Nothing doing, as expected. I was hoping Aleks' acid/base method would be the answer, but from Todd's reply we might need HTP. Any experience with lard anyone? David T. __ Do You Yahoo!? HotJobs - Search Thousands of New Jobs http://www.hotjobs.com Yahoo! Groups Sponsor -~-- 4 DVDs Free +sp Join Now http://us.click.yahoo.com/pt6YBB/NXiEAA/mG3HAA/9bTolB/TM -~- Biofuels at Journey to Forever http://journeytoforever.org/biofuel.html Biofuel at WebConX http://www.webconx.dns2go.com/2000/biofuel/biofuel.htm List messages are archived at the Info-Archive at NNYTech: http://archive.nnytech.net/ To unsubscribe from this group, send an email to: [EMAIL PROTECTED] Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
Re: [biofuels-biz] Re: hi ffa feed stocks
Thanks for your response, prof. Allen. I'll formulate an inquiry to Mohammed Farid as you suggest. You mentioned Thai railway application. I saw somewhere that German railways are using SVO in some of their shunting engines. The encouraging part of your message is you are reacting at 60C and that this is near methanol boiling point. That implies you are succeeding at atmospheric pressure. Do you use conc. sulphuric acid first stage? I agree meth recovery is so simple that using excess is not really a problem. David T. Yahoo! Groups Sponsor -~-- 4 DVDs Free +sp Join Now http://us.click.yahoo.com/pt6YBB/NXiEAA/mG3HAA/9bTolB/TM -~- Biofuels at Journey to Forever http://journeytoforever.org/biofuel.html Biofuel at WebConX http://www.webconx.dns2go.com/2000/biofuel/biofuel.htm List messages are archived at the Info-Archive at NNYTech: http://archive.nnytech.net/ To unsubscribe from this group, send an email to: [EMAIL PROTECTED] Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
Re: [biofuels-biz] Re: hi ffa feed stocks
Thanks for your response, prof. Allen. I'll formulate an inquiry to Mohammed Farid as you suggest. You mentioned Thai railway application. I saw somewhere that German railways are using SVO in some of their shunting engines. http://www.wired.com/news/technology/0,1282,53591,00.html Choo-Choo Trains on Energy Crunch The encouraging part of your message is you are reacting at 60C and that this is near methanol boiling point. That implies you are succeeding at atmospheric pressure. Do you use conc. sulphuric acid first stage? I agree meth recovery is so simple that using excess is not really a problem. David T. Yahoo! Groups Sponsor -~-- 4 DVDs Free +sp Join Now http://us.click.yahoo.com/pt6YBB/NXiEAA/mG3HAA/9bTolB/TM -~- Biofuels at Journey to Forever http://journeytoforever.org/biofuel.html Biofuel at WebConX http://www.webconx.dns2go.com/2000/biofuel/biofuel.htm List messages are archived at the Info-Archive at NNYTech: http://archive.nnytech.net/ To unsubscribe from this group, send an email to: [EMAIL PROTECTED] Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
Re: [biofuels-biz] Re: hi ffa feed stocks
Your wastewater treatment plant ought to compensate you nicely
for taking charge of the grease trap waste. No doubt they would
be happy to pawn their grease skimmings off on you as well.
FFAs...Theoretical limit or physical limit?
I don't believe Aleks lays a claim to any exact high point of
FFAs which can be converted when following the procedure outlined
in his ambient pressure method. At ambient pressure the primary
limiting factors are reaction time and diluted catalyst.
To establish a physical limit a series of tests would have to be
conducted. Even then, the results would be dependant upon time
limit. Some would have no problem with letting the reaction
extend for a lengthy period. Others would be more inclined
towards the McDonalds' drive thru method.
Todd Swearingen
- Original Message -
From: movember [EMAIL PROTECTED]
To: biofuels-biz@yahoogroups.com
Sent: Tuesday, August 20, 2002 10:14 PM
Subject: [biofuels-biz] Re: hi ffa feed stocks
The high-ffa feedstock is from industrial food waste and grease
traps. It doesn't smell very nice either!
Out of interest, what is the upper limit of FFA that would be
suited
to standard pressure, ~60 degrees C, Aleks-style two-stage
processing?
--- In [EMAIL PROTECTED], Appal Energy [EMAIL PROTECTED] wrote:
Yes. HTP is required to obtain high esterification conversion
on
such material. I would suggest that you seek out your nearest
college's chemistry department head and/or chemical
engineering
department to determine exactly what ballpark you will be in
relative to pressure and temp. They may also be willing to
assist you with the sampling
85% FFA feedstock is not derived from your run of the mill
fish
and chips outlet. It sounds more as if it's soap stock that
has
been removed during oil processing.
Todd Swearingen
- Original Message -
From: movember [EMAIL PROTECTED]
To: [EMAIL PROTECTED]
Sent: Monday, August 19, 2002 9:03 PM
Subject: [biofuels-biz] Re: hi ffa feed stocks
I am able to source large quantities of the high ffa
feedstock
(FFA
85%), however initial miniature tests (1 litre batches
using
Aleks'
two stage Acid/Base method) have proved unsuccessful.
Would the same process, under high Temperature/Pressure, be
sufficient to convert feedstocks of this type? If this may
be
the
case, then what mini-batch experiments could be done to
test
the
feedstock?
Much apreciated.
--- In [EMAIL PROTECTED], Appal Energy [EMAIL PROTECTED]
wrote:
It's a bit difficult to say that acid/base catalysis
falls
down, whether it be the ambient procedure as presented
by
Aleks
Kac or a HTP industrial procedure.
Most of what industry achieves under high pressure and
temperature can be achieved at STP by conducting the
reaction
over prolonged periods, at moderate temperature and in
several
stages when necessary.
To date we have experienced repeated success with STP
esterification, simply by prolonging the esterification
period to
36-48 hours, generating a complete transesterification
reaction
on 3.5% FFA feedstock with but 1.5 grams of KOH per liter
of
oil
over a 36 hour period.
Whether a repeat cycle is used on the esterification side
or
not,
it is necessary to separate the feedstock from any layers
that
formed during the esterification prior to conducting the
repeat
cycle or the base stage.
Todd Swearingen
- Original Message -
From: goat industries [EMAIL PROTECTED]
To: [EMAIL PROTECTED]
Sent: Monday, August 19, 2002 4:19 PM
Subject: [biofuels-biz] hi ffa feed stocks
Check out work done by Canakci and Van Gerpen. I'm
trying
out
their ideas,
but finding it difficult to get good results. Also, an
acid
value of 1mg
KOH/g = 0.5 % FFA. They identiified water formation in
the
acid
stage as the
inhibiting part of the reaction, which is where Alek's
'foolproof' method
falls down (apparently).
Yahoo! Groups
Sponsor -~--
4 DVDs Free +sp Join Now
http://us.click.yahoo.com/pt6YBB/NXiEAA/Ey.GAA/9bTolB/TM
---
--~-
Biofuels at Journey to Forever
http://journeytoforever.org/biofuel.html
Biofuel at WebConX
http://www.webconx.dns2go.com/2000/biofuel/biofuel.htm
List messages are archived at the Info-Archive at
NNYTech:
http://archive.nnytech.net/
To unsubscribe from this group, send an email to:
[EMAIL PROTECTED]
Your use of Yahoo! Groups is subject to
http://docs.yahoo.com/info/terms/
Yahoo! Groups
Sponsor -~--
4 DVDs Free +sp Join Now
http://us.click.yahoo.com/pt6YBB/NXiEAA/Ey.GAA/9bTolB/TM
Re: [biofuels-biz] Re: hi ffa feed stocks
Yes. HTP is required to obtain high esterification conversion on
such material. I would suggest that you seek out your nearest
college's chemistry department head and/or chemical engineering
department to determine exactly what ballpark you will be in
relative to pressure and temp. They may also be willing to
assist you with the sampling
85% FFA feedstock is not derived from your run of the mill fish
and chips outlet. It sounds more as if it's soap stock that has
been removed during oil processing.
Todd Swearingen
- Original Message -
From: movember [EMAIL PROTECTED]
To: biofuels-biz@yahoogroups.com
Sent: Monday, August 19, 2002 9:03 PM
Subject: [biofuels-biz] Re: hi ffa feed stocks
I am able to source large quantities of the high ffa feedstock
(FFA
85%), however initial miniature tests (1 litre batches using
Aleks'
two stage Acid/Base method) have proved unsuccessful.
Would the same process, under high Temperature/Pressure, be
sufficient to convert feedstocks of this type? If this may be
the
case, then what mini-batch experiments could be done to test
the
feedstock?
Much apreciated.
--- In [EMAIL PROTECTED], Appal Energy [EMAIL PROTECTED] wrote:
It's a bit difficult to say that acid/base catalysis falls
down, whether it be the ambient procedure as presented by
Aleks
Kac or a HTP industrial procedure.
Most of what industry achieves under high pressure and
temperature can be achieved at STP by conducting the reaction
over prolonged periods, at moderate temperature and in
several
stages when necessary.
To date we have experienced repeated success with STP
esterification, simply by prolonging the esterification
period to
36-48 hours, generating a complete transesterification
reaction
on 3.5% FFA feedstock with but 1.5 grams of KOH per liter of
oil
over a 36 hour period.
Whether a repeat cycle is used on the esterification side or
not,
it is necessary to separate the feedstock from any layers
that
formed during the esterification prior to conducting the
repeat
cycle or the base stage.
Todd Swearingen
- Original Message -
From: goat industries [EMAIL PROTECTED]
To: [EMAIL PROTECTED]
Sent: Monday, August 19, 2002 4:19 PM
Subject: [biofuels-biz] hi ffa feed stocks
Check out work done by Canakci and Van Gerpen. I'm trying
out
their ideas,
but finding it difficult to get good results. Also, an acid
value of 1mg
KOH/g = 0.5 % FFA. They identiified water formation in the
acid
stage as the
inhibiting part of the reaction, which is where Alek's
'foolproof' method
falls down (apparently).
Yahoo! Groups
Sponsor -~--
4 DVDs Free +sp Join Now
http://us.click.yahoo.com/pt6YBB/NXiEAA/Ey.GAA/9bTolB/TM
---
--~-
Biofuels at Journey to Forever
http://journeytoforever.org/biofuel.html
Biofuel at WebConX
http://www.webconx.dns2go.com/2000/biofuel/biofuel.htm
List messages are archived at the Info-Archive at NNYTech:
http://archive.nnytech.net/
To unsubscribe from this group, send an email to:
[EMAIL PROTECTED]
Your use of Yahoo! Groups is subject to
http://docs.yahoo.com/info/terms/
Yahoo! Groups
Sponsor -~--
4 DVDs Free +sp Join Now
http://us.click.yahoo.com/pt6YBB/NXiEAA/Ey.GAA/9bTolB/TM
---
--~-
Biofuels at Journey to Forever
http://journeytoforever.org/biofuel.html
Biofuel at WebConX
http://www.webconx.dns2go.com/2000/biofuel/biofuel.htm
List messages are archived at the Info-Archive at NNYTech:
http://archive.nnytech.net/
To unsubscribe from this group, send an email to:
[EMAIL PROTECTED]
Your use of Yahoo! Groups is subject to
http://docs.yahoo.com/info/terms/
Yahoo! Groups Sponsor -~--
4 DVDs Free +sp Join Now
http://us.click.yahoo.com/pt6YBB/NXiEAA/Ey.GAA/9bTolB/TM
-~-
Biofuels at Journey to Forever
http://journeytoforever.org/biofuel.html
Biofuel at WebConX
http://www.webconx.dns2go.com/2000/biofuel/biofuel.htm
List messages are archived at the Info-Archive at NNYTech:
http://archive.nnytech.net/
To unsubscribe from this group, send an email to:
[EMAIL PROTECTED]
Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
