Any time you can convert waste that would otherwise have ended up into fuel and other useful by-products, you're solving two problems at once. Using a plasma torch for the purpose suggests this particular process is rather energy intensive, though.

Another company with similar claims with a rather more low-tech approach is Changing World Technologies, who have built a demonstration plant next to ConAgra's Butterball turkey abatoir in Carthage, Missouri.

http://thermal-depolymerization.area51.ipupdater.com/

The plant was shut down at one point because nearby residents complained of foul odors - presumably from turkey carcasses rather than the TDP process as such.

Brilliant,somehow I posted as Rafael.The post with the Spock reference is mine.

why process Ethanol? Ethanol has a genreous subsidy.

180-200 proof ethanol is a much cleaner fuel than gasoline and diesel fuel. It is about the lowest emission fuel we could use. It has a much higher octane than gasoline which means higher compression ratio could compensate for lower energy density.

Alan -

technically, you are right. However, with appropriate operating parameters, TDP can deal with just about any feedstock featuring long-chained organic molecules. This includes abatoir waste, corn stovers, hospital waste, sewage, municipal waste, tires etc. The result is something akin to a light sweet crude and refined into No2 and No4 gasoil. These can be used as-is for transportation and space heating, respectively. At today's prices, TDP diesel is profitable in its own right and of course, ConAgra avoids expensive landfill charges. This will become even more significant once avian flu hits the US (sadly, just a matter of time).

Going down all the way to CO and H2 and then synthesizing whatever compounds you like is possible but I have a hunch it's even more expensive.

Solid feedstock presumably would need to be crushed and dried, both energy sapping processes. A viable plant would need to process several tons per hour; it is not stated whether off-the-shelf plasma torches can do this. How much of the syngas needs to be burned to power the torch? Hopefully this would be less than 50%, net of any heat recovery. Lastly the fuel synthesis process itself has energy losses. This chain could have more than one weak link.

We have people here in Boulder County that have gotten their trash load down to almost zero waste through recycling and composting. This seems like a more elegant long term solution to the problem. The goal is to get the whole county to almost zero unrecycled or unreused waste.

We don't really have enough info on TDP to know exactly how it works. Just because the name says "depolymerization" does not mean it can only break large molecules into smaller ones. Think the chemistry is affected by the name the inventor chose? Notice that CWT has recently started using the name "thermal conversion process" for that very reason, I suspect.

Of course, good technical information on TDP is a rarity. One of the better sources is a lecture Dr. Terry Adams gave at MIT (http://web.mit.edu/10.391J/www/ click on "Lecture Notes" and then on "April 5, 2005, The CWT Thermal Conversion Process (Guest speaker: Dr. Terry Adams)". If you read through that it sounds asif the Carthage Plant basically consists of three steps:
1. A Thermo-Acid Hydrolysis Step that sounds suspiciously like Dilute Acid Hydrolysis, see http://www.eere.energy.gov/biomass/dilute_acid.html This step converts all biopolymers to their monomers. In the case of turkey guts, protein is broken down to amino acids. Fat is converted to fatty acids and glycerol.
2. Separation of fat and water. The importance of this step is that the water-soluble organics (a significant part including glycerol and 2/3 of amino acids) ends up in the effluent. This makes claims of 85% energy efficiency highly dubious. CWT has a good answer for that: "Amino acids are good fertilizer." Bit of waste of amino acids, I would think. Good salemanship from CWT, though.
3. The fat part then goes to the second stage where the main reaction is decarboxylation (converting fatty acid to oil) and a secondary reaction is deamination (which together with decarboxylation would convert some amino acids into oil).

If this is the way all TDP plants work, then it has rather limited application. The bulk of the promising feedstock out there is carbohydrate. The monomers of carbohydrates are water-soluble sugars. If these would end up in the effluent, TDP would not be able to do anything with a carbohydrate feedstock.

Can carbohydrates (C5 and C6) be converted to oil (C8 and higher)? Yes it can, see http://w3.tm.tue.nl/fileadmin/tm/TDO/Prof.J.Dumesic.pdf Note however that these are lab conditions, pure substances, very predictable chemistry, etc. Whether it works in the real world remains to be seen.

Link to previous GCC story on Butanol. It would seem to be superior to ethanol in many ways.

If you having problem with compost pile, why not consider anaerobic digester? Capture the methane and you will produce both fuel and nutrient as end product. Plus no plasma is needed in the process, only need a little time.

This whole notion of developing these kinds of fuel/ bioreactors as a more consumer usable product comes up. There are just a lot of issues to overcome in terms of smell and safety, but if properly maintained it seems like a simple, automated system could be developed to serve a small village or community for waste management, compost, heat and energy needs.

can we use biogas in automobiles?