PHOTO: COLUSA BIOMASS ENERGY CORP.
cellulose
Using a modified forage harvester, right, CBEC successfully completed a large-scale rice straw harvest last fall. The harvester collects and chops the straw, then blows it into walking floor trailers that hold 9 to 14 tons.
Arkansas, where rice mills have a problem disposing of hulls. There is no ban against burning straw in Arkansas, so there is no real incentive to collect it and therefore the infrastructure is less developed there than in California. But Arkansas is home to several large rice mills where hulls accumulate rapidly, so collocating near a mill is a wise choice
and virtually eliminates the grueling task of honing an efficient method of aggregation, storage and delivery. According to Nannen, ongoing discussions with Riceland Foods and Producers Co-op for feedstock arrangements are encouraging. Riceland Foods gasifies a portion of its hulls for some of the energy required in milling operations, and has for many
years. “I don’t know how efficient that technology is anymore,” Nannen says. Bowers adds, “They use the hulls to generate the heat for their parboiling operations. That worked really well 15 to 18 years ago but not necessarily so well now because of the advances in combustion techniques with other materials that have come along, so it was a leading situation years ago but it’s not the same today— and there might be a better use for those hulls from an income point of view for the rice mills, and it could certainly be the basis for transportation fuels.” Rice hulls contain 20 percent silica whereas the straw contains 12 percent. “If the economics allow us on the front end, I could see us building both these plants with completion dates within six months of each other,” Bowers tells Biomass Magazine. Two states, two companies and one mission: Being the first project development team to build the first commercial ethanol and specialty-chemicals plant using difficult but globally abundant rice waste. BIO Ron Kotrba is a Biomass Magazine senior writer. Reach him at rkotrba@bbibiofuels .com or (701) 738-4962.
2|2008 BIOMASS MAGAZINE 25