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Issue 36 May, 1998 Published by AG-WEST BIOTECH INC.

Agbiotech Information Bulletin for Schools courtesy of Ag-West Biotech Inc.

Biotechnology and Fuel: Renewable Energy ResourceA province like Saskatchewan has the advantage of clean

air and open spaces. However, the more we use cars andtrucks to conquer those open spaces, the less likely it is thatthe air will remain clean. Burning non-renewable fossil fuelsis a major source of air pollution. Biotechnology is providingsome solutions to this environmental problem.

Ethanol, a clean-burning fuel which comes from renew-able sources, is a product of biotechnology. Conventionalethanol production involves fermenting grain like wheat andcorn. Research is now being conducted to produce ethanolfrom products that are now considered waste, like the sludgefrom pulp and paper production, yard waste like leaves and

other solid waste dumped in municipal landfills.

Total ethanol production in Canada is about 55 millionlitres a year, with 17 million litres being used as fuel and therest going to industrial uses. Industrial ethanol is used as asolvent in products such as toiletries, cosmetics and medica-

tions for external use. In Saskatchewan, the PoundMaker

ethanol plant at Lanigan has the capacity to produce about 13million litres per year. This plant is integrated with a feedlot.Beef cattle are fed the distillers grain which is a byproduct ofthe ethanol production process.

Ethanol production in the United States is considerably

higher. About 6 billion litres are produced each year.

Fields of Fuel

Ethanol made from wheat is created through the process offermentation. Fermentation is a series of biochemicalreactions, using microorganisms like yeast, which yields

ethanol. Several different types of wheat can be used, includ-ing durum, hard red spring and hard red winter wheat.

The process begins with cleaning and milling of the wholewheat kernel. Then a special enzyme (a naturally occurringsubstance), which can withstand high temperatures, is added,and the wheat is cooked at 95C. This process of enzymetreatment and cooking breaks down the starch in the wheat.

Then the mash is cooled to 30C, the temperature at whichfermentation can take place. Another enzyme, called

amyloglucosidase, is added, along with a yeast calledSaccharomyces cerevisiae.

The enzyme and the yeast work together to ferment the

wheat mash. The enzyme slowly releases glucose, a sugar.The glucose is immediately used by the yeast, and the processof fermentation occurs. The fermentation is usually complete

in 56 hours. The process ofdistillation then recovers theethanol. The water is removed from the ethanol, eitherthrough filtration or treatment with a chemical.

The mash that is left over from the fermentation processcan be fed to beef cattle as distillers grain. Use of the by-product in this way reduces the need for cattle feed produc-tion, reduces the cost of ethanol production and helps producea valuable consumer product.

Fuel Ethanol Production from Wheat

Alternate Feedstock for an Alternate Fuel

Other materials, or feed stocks, which can be used toproduce ethanol include waste sludge from pulp and papermills, waste paper, grass, straw, leaves and other solid landfill

wastes that contain cellulose, or plant fibres.

Research has previously focused on using agricultural

Whole Grain

Cleaning

Cooking with Enzyme Added

Combined sugar production and fermentation

Distillation

Filtration Cattle feed

Ethanol

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Published byThe Signature Group Inc., 608 Duchess Street

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Funding assistance provided bySaskatchewan Agriculture and Food

However, sludge from the pulp and paper industry could

be considered a free feedstock because it is a waste productthat would otherwise require disposal. It is generated on anongoing basis, so there would be no need to stockpile it. Thepulp and paper industry in Canada produces at least 1.3million tonnes of sludge each year. The year-round supplywould also eliminate problems with spoilage, which couldoccur with agricultural products like straw.

The wood fibres in pulp and paper sludge have also beenpre-treated in the pulp-making process. Since the cellulose hasalready been partly broken down, the sludge could requireless processing than other ethanol plant feedstocks.

Creating Fuel from a Waste Product

Scientists at the Saskatchewan Research Council(SRC) Bioprocessing Laboratory in Saskatoon haveshown that sludge from pulp and paper production can be

used to make ethanol.

They first created a database of the composition of the

different types of sludge created by various pulping processes.Sludge varies in composition, depending on the amount ofrecycled materials being used to make different paper prod-ucts. Each time paper is recycled, the resulting sludge con-

tains more wood fibre.

The scientists used the database to evaluate variousprocessing methods and the potential ethanol yield from eachtype of sludge.

They determined that pulp and paper sludge containsbetween 45 per cent to 70 per cent cellulose. Thats the plantfibre which is converted to glucose for ethanol production.

Straw is only about 30 per cent cellulose. In general, theresearchers found that sludge is a cheaper option for ethanolproduction than material like straw.

The process of making ethanol from pulp and paper sludgeis similar to the process used in making ethanol from wheat.The sludge is pre-treated to further break down the cellulose.Enzymes are added to convert the cellulose to glucose. Then

yeast or, in some cases, genetically alteredbacteria, areadded to create the fermentation process. The mixture is thendistilled to produce ethanol.

wastes like straw, and solid landfill wastes. These products arethought to be free because they dont have any marketvalue. However, there are costs associated with these freefeedstocks. For example, there is the cost of transporting thematerial, and in some cases (such as straw, which is harvested

once a year), stockpiling it. There is also a cost involved inseparating the materials which contain cellulose from landfillwaste. Some of this material would also have to be treatedbefore it could be used.

Researchers predict considerable potential for the use ofsludge and other cellulose-based feedstocks for ethanolproduction. One company which produces enzymes forcellulose treatment, Logen Corp. in Ottawa, is working withPetroCanada to build a $30-million pilot plant. The plantwould convert cellulose-based feedstocks to ethanol.

The use of biotechnology is not only creating a clean fuelwhich can reduce the use of fossil fuels, it also offers potentiafor further environmental protection through the utilization ofwaste products.

Special thanks to Dr. Krystyna Sosulski of the Saskatchewan

Research Council for her help in preparing this Infosource.

Fuel Ethanol Production from Pulp and Paper Waste

Sludge Feedstock

Pre-treatment

Enzyme treatment

Fermentation

Distillation

Ethanol