Researchers Develop New Continuous Transesterification Process for Biodiesel Production
08 March 2008
The Mcgyan process. Click to enlarge. |
Researchers at Augsburg College and SarTec Corporation have developed and are commercializing a new continuous transesterification process for the production of biodiesel. The “Mcgyan Process”—so termed based on the names of the inventors (McNeff, Gyberg and Yan)—can use a wide variety of feedstocks, does not consume the catalyst, reduces the reaction time from hours to seconds, and uses no water or dangerous chemicals.
An alcohol and a lipid (vegetable oil or tallow) are combined by high pressure pumps into a lipid stream that is passed through a continuous fixed-bed reactor filled with a sulfated metal oxide catalyst at elevated temperature and pressure. The reactor performs transesterification and esterification reactions simultaneously.
The output contains excess alcohol and biodiesel fuel. The fuel is then distilled to recover the excess alcohol and other coproducts, and the biodiesel is polished to remove residual free fatty acids, which can be recovered and put back into the input side of the system.
Benefits of the Mcgyan process, according to the inventors, are:
Flexible feedstock; animal or plant sources of lipids can be used. Current waste products can be turned into fuel.
No use of strong acids or bases in the process.
Fast reaction times (seconds).
Cheap feedstocks such as waste grease and animal tallow as well as a variety of plant oils can be converted to biodiesel.
The metal oxide based catalyst is a contained in a fixed bed reactor thereby eliminating the current need to continuously add catalyst to the reaction mixture thereby reducing the amount of waste produced.
Unwanted side reactions with free fatty acids producing soaps are eliminated, thereby reducing the amount of waste that must be disposed of properly.
Insensitive to free fatty acid and water content of the feedstocks.
The catalyst does not poison over time.
A patent is now pending on the Mcgyan process. Ever Cat Fuels Corporation is a new company currently producing 50,000 gallons of biodiesel per year using the Mcgyan process. Its production capacity will increase to 3 million gallons per year when a new plant begins operation in Isanti (MN) later this year. Then, Ever Cat Fuels hopes to sell the technology and equipment globally.
Where does the glycerin end up?
Posted by: Peter P. | 08 March 2008 at 10:47 AM
Concerning the glycerin...
My guess is that it is fed back into the system given the schematic. Recall that glycerin is a sugar alcohol.
Only a guess of course.
Posted by: sagneta | 08 March 2008 at 12:42 PM
There have been earlier announcements on GCC about 'microchannels' and supercritical methanol as more efficient approaches to biodiesel. However given that algae hasn't worked out it looks like there will never be enough lipids feedstocks. We need some kind of miniturisation breakthrough for cellulose based fuels.
Posted by: Aussie | 08 March 2008 at 01:31 PM
This could be an important part of the process for biodiesel.
The questions they don't answer are economics and EROIE.
How much energy does this process consume? There's a lot of heating and pressurization going on. How much do the materials cost? The answers are probably perfectly acceptable, and substantial improvements, but it would be good to confirm.
Posted by: Healthy Breaze | 08 March 2008 at 02:38 PM
This sounds a bit suspect, or maybe it is all PR hype. They casually mention that co-products are formed and get separated out in distillation and that the fuel gets polished to remove residual free fatty acids. They seem to over state the simplicity (they even state that no glycerol is formed on their website), but the fact is that there still are additional processing and purification steps that are required. There are at least 5 other solid catalyst biodiesel processes out there (eg NCL out of India) and there are other continuous biodiesel processes too.
They even claim that the catalyst never gets poisoned, which seems unlikely if you use "any" feedstock.
Posted by: jc777 | 08 March 2008 at 04:12 PM
Wait, who said algae won't work?
Posted by: Ben | 08 March 2008 at 07:20 PM
I am also interested in where the glycerol goes. Unless they do not form it in the first place. They claim to not use large quantities of strong bases, so perhaps there is limited glycerin production.
Another algae naysayer (Aussie)...
ECF claims success with refined algae oil.
Algaes are some of the most efficient converters of water and CO2 (waste CO2 from coal fired utilities too) to biofuel feedstocks. Algal celluloses are easily milled for conversion to alcohols, and the oils are readily convertable to biodiesel. They do not waste energy producing complex support structures or roots, just more algae cells. Just try smearing corn stover, sorghum, or cane bagasse into a paste between your fingers. Easily milled to a fineness for enzymatic conversion to sugars, and removal of fats. Other crop wastes have their place in biofuels production, use the stover, surplus fruit, cottonseed oils, yard waste, etc. But when it come time for a total replacement of petrofuels with biofuels, only algaes can produce the quantities of feedstocks needed to replace the 6+ billion barrels of petroleum we use anually for motor fuels, and heating, without converting all land in the US for biofuel feedstocks. Remember ya gotta flatten the Rockies to fill in the Great Lakes, cause we will need those acres too.
Can anyone envision trying to inject waste CO2 into a 100 acre corn, or soybean field?
Posted by: Eric | 08 March 2008 at 09:36 PM
Folks:
1. Any transesterification process that claims it does not produce glycerin is a fraud; check your chemistry 101 text book!
2. There is nothing new about fluidized bed reactors with a catalyst bed that is not consumed in the process; Europeans have already built similar commercial scale plants but it hasn't helped them overcome the skyrocketing cost of rapeseed and other feedstock.
3. The capital cost of the Mcgyan plant will be higher than other processes, and they don't tell you how long their expensive catalyst will last in a commercial plant, or when a waste oil feedstock contains sulfur and /or metals;
4. The pain now being felt by biodiesel producers has nothing to do with reactors and catalysts, but is almost entirely caused by the exorbitant cost of feedstock; NaOH and KOH, and other conventional catalyst are relatively cheap commodity chemicals.
5. There is not enough waste oil on this planet to put a dent in either petroleum diesel consumption or CO2 emissions, and food based oils are too expensive to build a sustainable fuel industry;
6. We now know that in a biodiesel spill, bacteria in the ground will break the methyl ester down into methanol and oil, leaving a toxic plume to contaminate ground water. This may be worse than a Green Diesel spill, which is converted to methane.
7. All waste lipids and other biomass should be gasified to produce liquid fuels, electricity, biomethane, bio-hydrogen, bioplastics, etc., and subsidies should be eliminated for all food crop fuels worldwide.
Posted by: MeanandGreen | 09 March 2008 at 11:38 AM
Regarding the glycerol: have anyone ever considered that they may be processing fatty acids rather than triglycerides? It says the process is insensitive to fatty acids and a sulphated metal catalyst does sound like an anionic catalytist similar to the one produced by Lewatit.
Posted by: Fidel | 10 March 2008 at 12:16 AM
I bet the glycerin is further reacted into something else. This reaction occurs at a MUCH HIGHER TEMPERATURE than your typical transesterification reaction.
Also, as was stated previously feedstock cost is the primary cost driver for biodiesel producers. The beauty of this process is that it allows one to use ANY feedstock. Higher FFA feedstocks are usually much less expensive and cannot be used in the traditional process.
Posted by: zirchrom | 10 March 2008 at 06:36 AM
But with TGs where does the glycerin go? It doesn't just get "converted" into something else. Glycerin forms it has to, it is the product of the TE reaction. Where does it go? Much of it will physically settle with the excess alcohols, if that is what they are doing, but they don't say what they do with it then. Do they distill the methanol from the glycerol? Do they dispose of it? Do they send the glycerol/methanol mixture as reflux back to the reaction to improve kinetics? Doubtful, that is accumulation, which a true continuous process would be free of.
Also if they were just esterifying free fatty acids, what you get is biodiesel and water, not biodiesel and alcohol.
And we all should know (if we're bd producers) that trans-esterification of TGs will yield bd and glycerol. It doesn't just vanish out of thin air.
The purpose of supercritical heated methanol is to increase the activity coefficent (which increases/improves conversion and pushes the equilibrium of the reaction to the right). That way you don't need to compensate by adding more catalyst or a higher methanol ratio (6:1 vs 3:1). Although, if they are getting excess methanol in the recovery stream, they are most certainly using a higher molar ratio (not necessary for supercritical reactions).
This process has been introduced in many forms before. Its advantages are less methanol to use and recover, less catalyst (or in many cases no catalyst), and faster processing time. But supercritical conditions are often unstable, difficult to control, and in the case of a reagent as volatile as methanol unsafe. A good, safe design that can do all this is great, possibly very expensive though.
I'd like to see how this process develops and is evolved. But the company may want to work on their delivery when presenting to BD producers.
Posted by: ECE | 07 April 2008 at 04:33 PM
The Ever Cat Fuels website indicates oils are used as feedstock and only a trace of glycerol is produced. So glycerol must somehow be getting converted to methanol, requiring the unlikely addition of hydrogen into the C-C bonds of glycerol! If this is the case where would the H come from - dehydrogenation of the fatty acid chains? Truly revolutionary chemistry!
Posted by: Hugh | 16 May 2008 at 03:06 AM
The Ever Cat Fuels website indicates oils are used as feedstock and only a trace of glycerol is produced. So glycerol must somehow be getting converted to methanol, requiring the unlikely addition of hydrogen into the C-C bonds of glycerol! If this is the case where would the H come from - dehydrogenation of the fatty acid chains? Truly revolutionary chemistry!
Posted by: Hugh | 16 May 2008 at 03:07 AM
It is very good to have a fast efficient reaction available that is actually in production. How about a home version called BIO-PHILL...HG...
Posted by: Henry Gibson | 23 May 2008 at 10:00 PM
Folks! See our PCT/HU 2008/000013 patent application. We transesterify (or rather: interesterify) triglycerides with alkyl-esters of short-chain fatty acids (preferably with 100% bio-derived ethyl-acetate), BUT only partially, whereby we get a mixture of modified triglicerides (with 50-70% newly introduced short chains), with reduced molecular masses, that is, with greatly reduced viscosities, and alkyl (ethyl) esters of displaced long chain fatty acids (that is, traditional biodiesel). There is no glycerol formation, but each and every atom of the biomass TG is turned into fuel, yielding 15-20% more combustible out of a given amount of feedstock! (In other words: you need 15-20% LESS arable land to produce a given volume of biofuel. Most important issue these days.). No washings, no sewage, but 30% greater internal oxygen content, better emission profile, less soot, greater torque, lowered iodine number, better cold-properties, etc. And all this with lower production costs. To date ours is the ONLY really 100% renewable petrodiesel substitute (as the methanolic part of BD comes from methane, that is, a fossil). Well?
Posted by: Janos THESZ | 07 June 2008 at 07:22 AM
They state "thereby reducing the amount of waste that must be disposed of properly". The glycerol can be used for methane production or used for making soap, or even composted.
Posted by: Ron | 08 November 2008 at 12:48 PM