Title: Biofuels and bioenergy production from municipal solid waste commingled with agriculturally-derived biomass. Authors
Submitted to: Sustainable Feedstocks for Advanced Biofuels
Publication Type: Book / Chapter
Publication Acceptance Date: September 28, 2010
Publication Date: September 28, 2010
Citation: Holtman, K.M., Bozzi, D.V., Franquivillanueva, D.M., Orts, W.J. 2010. Biofuels and bioenergy production from municipal solid waste commingled with agriculturally-derived biomass. Sustainable Feedstocks for Advanced Biofuels. Ch. 14, pp. 237-247. Interpretive Summary: MSW provides stability – both in consistency of supply and infrastructure development– while herbaceous feedstocks supply the potential for the quantities needed to meet our energy needs. MSW can be a reliable supplement to herbaceous feedstocks specifically because it is available on a daily basis through transportation networks that have been developed and optimized. Cellulosics from MSW after separation are comparable to commodity lignocellulosics and can be utilized to help jumpstart the cellulosic ethanol industry due to the relatively low cost of separation and the advantages related to locality and transportation. Availability is both consistent and predictable, with feedstock contracts usually held by single parties. Given these benefits, it is valuable to look more closely at initially utilizing this resource to start operation with the later potential of commingling MSW with herbaceous feedstocks, and identify what might be needed to assist operational application. This paper discusses a pilot study of commingling MSW with agriculturally- derived feedstocks for the production of either ethanol and/or biogas.
Technical Abstract: The USDA in partnership with Salinas Valley Solid Waste Authority (SVSWA) and CR3, a technology holding company from Reno, NV, has introduced a biorefinery concept whereby agriculturally- derived biomass is commingled with municipal solid waste (MSW) to produce bioenergy. This team, which originally developed an autoclaving technology to pretreat MSW, has installed and operated a pilot- scale (2 T per batch) steam autoclave to evaluate its use for producing biofuels from waste biomass. Through this collaboration the SVSWA has arrived at the decision to commercialize autoclaving of their MSW with the intention of producing bioenergy from the cellulosic fraction from MSW. The autoclave has also been applied as a front- end technology to pretreat an array of different biomass feedstocks for energy production. Commingled feedstocks that have been test autoclaved in this system include rice straw, wheat straw, grape pomace, olive industry waste, wax board, cardboard, food wastes, leafy vegetable wastes, and fast- food garbage. These streams were autoclaved and converted to bioenergy either alone and/or commingled with MSW. For each run the USDA research team provided data on the yields of methane production via anaerobic digestion versus ethanol yields via saccharification and fermentation; i.e., ethanol was produced from the isolated cellulose using typical commercial yeasts after dilute acid hydrolysis. In most cases results favored biomethane production as being more economically viable than ethanol production due to more efficient conversion and the scale of biomass availability. Specifically, the data from smaller scale operations generally point toward biogas production. The next step for the partnership is to demonstrate, at pilot scale, an anaerobic basin system developed at the USDA specifically for the purposes of producing biomethane from MSW commingled with agricultural wastes.