Colusa Biomas Ethanol Process

The CGBY process for producing ethanol from cellulosic materials is one of the new processes being developed which could enable production of quantities of ethanol in far excess of the quantities possible from corn.  Such processes are necessary if we are to make any progress in decreasing our dependence on imported oil.

Colusa Biomas Energy Corporation (CBGY) holds a patent on an acid pretreatment hydrolysis process, shown below, which first uses acid to convert the rice straw into 5-Carbon sugars and a silica/lignin streams.  The silica/lignin stream is then hydrolyzed into cellulose.  The cellulose and 5-C sugars are fermented to produce ethanol. The process is initially being developed for making ethanol from rice straw.  Disposal of rice straw in California, where Colusa is loacated, is a problem in that it was traditionally disposed of by burning which now has been banned by state law. The sequence of the process is as follows:

• Rice straw/hulls pass through a shredder.
• Shredded material is exposed to steam where the fibers are expanded and dilute sulfuric acid is added to the material.
• The material then passes to the first extractor where it flows counter currently to more acid solution.
• C-5 sugars are removed in the extractor leaving a Silica/Lignin extract.
• The C-5 sugars are fermented and distilled into ethanol.
• The lignin-silicate extract from the first extractor flows counter currently to caustic (NaOH) in a second extractor.
• This process places the silica and the lignin in solution.
• The caustic  converts a portion of the lignin into cellulose.
• The remaining lignin-silicate solution is removed from the second extractor and flows through a ultrafiltration system where the silicate solution is separated from the lignin solution resulting in a concentrating lignin solution which is used for fuel and a silica/sodium oxide byproduct.
• The hydrolyzed lignin, now cellulose, from the second extractor is fermented and and distilled into ethanol.
• The lignin fuel that was separated by the ultrafiltration system is used to provide energy for the operation of the plant.

According to the company's web site:

The process is suited for making ethanol from corn stover and cobs, wheat straw and husks, wood chips from forest slashing, and sawdust from saw mills....Using 2003 farm data from the US Department of Agriculture and taking into consideration the availability of these cellulose based materials, it has been conservatively estimated that over 1.0 trillion gallons of ethanol could be produced per year. This would reduce the importation of oil by an estimated 75%. CBGY will initially build a 50,000 ton/yr rice straw plant near Colusa, CA. This plant will produce 6.25 million gallons of fuel ethanol, 8,000 tons of silica products, Distillers’ Dried Grain Solubles (DDGS), commercial carbon dioxide, and a high energy lignin fuel that will be used internally in the plant to reduce the cost of natural gas

California rice farmer grows an acre of rice he gets about 8000 pounds of rice and 5000 pounds of rice straw....We have the proprietary technology to make an acre of waste rice straw into 313 gallons of fuel ethanol and 900 pounds of high quality silica for industry....CBGY has the ability to generate roughly $890 of revenue from an acre of waste rice straw-with 3,600,000 acres of rice being grown in the United States alone, let alone China, India and other countries,

I don't know how many other companies that are pursuing this route to ethanol.  This type of process has been referenced in DOE reports previously.  This type of technology is supposed to be the one of the most advanced that is this far along in development.  The new enzyme pretreatment processes are supposed to be less costly.  Iogen in Canada has an enzyme process that is further along than this one, but details of their process have not been revealed.  The DOE site, below, gives a summary of the status of bioethanol technology.

Resources:

Colusa Biomass Energy Corporation website http://www.colusabiomass.com/default.htm
"Colusa Biomass Energy Corporation Signs Consulting Agreement with TSS Consultants", Forbes.com, 8/4/05
"Bioethanol-Moving Into the Marketplace", Doe National Bioethanol Program

Technocrati tags: ethanol, renewable energy, biofuels

Comments

[JesseJenkins]

These cellulose-based biofuel refining processes are very exciting. Thanks for posting on this subject. Check out these other players in this area as well:

Ethanol:
Iogen - www.iogen.ca
BC International Corp - www.bcintlcorp.com
(BC International uses a modified E Coli bacterium strand in their refining process)
Novozymes - http://www.novozymes.com/cgi-bin/bvisapi.dll/solutions/solutions.jsp?cid=-10404&id=20752

Biodeisel:
Novozymes (again)
GreenFuel (algael biofuel refining) - www.greenfuelonline.com

[Sam]

Indeed, cellulosic ethanol is the fuel of the future.

This website shows the most complete list of companies in cellulose ethanol industry that I have found: www.investincelluloseethanol.com

[NARINDER M PARACER]

I WANT TO START THE ETHANOL PRODUCTION FROM THE RICE AND WHEAT STRAW> FOR THIS PURPOSE I NEED SOME TECHNICAL COLLEBRATION TO SET UP THE PLANT IN DIFFERENT PARTS OF INDIA

PLEASE ADVISE

NARINDER M PARACER

UJAGAR BIO PARK
NEW DELHI INDIA
+91-98 109 87944