feedstock The Creosote Controversy Creosote is a complex mixture of a hazardous nature that may serve as a fungicide, insecticide and sporicide in wood protection treatments. Despite being classified as a possible human carcinogen by the U.S. EPA, creosote remains the second most widely used wood preservative in the United States—primarily for treatment of industrial products such as railroad ties and utility poles. According to the Agency for Toxic Substances and Disease Registry, there are more than 300 identifiable chemicals in creosote, but as many as 10,000 more may be in the mixture. There is strong evidence of harm resulting from improper safety precautions, disposal and use. Because creosote is a restricted-use pesticide that can only be applied by certified applicators or someone under their direct supervision, it is not available for sale to or use by homeowners. However, the EPA has acknowledged in reports that some creosote treated wood such as in railroad ties are used outdoors in home landscaping, and that creosote does, in fact, have the capabilities of having negative health effects on animals, humans and the environment. On the contrary, a definite plus to creosote is that the chemical significantly prolongs the lifespan of wood, thus reducing the need to harvest new wood. Since more companies than ever before are gaining permits to accept creosoted wood to recycle for biomass, opponents and environmentalists want to know what is being done to ensure the toxins are being properly removed—and if it is really environmentally safe. Enerkem, a leading producer of cellulosic biofuels, has developed a new technology to remove contaminates such as creosote from wood using a gasification and catalysis process.
poles and creosote treated wood—that most corporations cannot, because of permit limitations preserving air quality and the environment. Enerkem has recently partnered with GreenField Ethanol, Canada’s leading ethanol producer, and is in the midst of constructing the company’s first commercial-scale plant in Westbury, Québec, along with a series of other projects in Canada. Enerkem is colocated with a saw mill that recycles the middle part of the decommissioned power poles into construction wood, such as 2x4s. The remaining treated portions
containing impurities cannot be recycled into construction wood. These pole residues are transformed into wood chips by the saw mill and transferred to Enerkem to be converted into ethanol. In the first step, the wood chips or other feedstocks are dried, sorted and shredded to be stored in a container that is connected to the gasifier by a front-end feeding system capable of handling fluffy material, without the need to pelletize. Slurries or liquids may also be fed into the gasifier through appropriately designed injectors. The carbonaceous materi-
Enerkem Emerges Enerkem, founded in 2000, is headquartered in Montreal. The company has operated a pilot plant in Sherbrooke, Québec, since 2003—testing a new gasification and catalytic synthesis technology. The unique factor Enerkem possesses is the ability to process certain types of demolition wood—such as decommissioned power
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