(729d) Effect of Feedstock Formatting on Gasification Performance for Hyprid Poplar, Corn Stover and Low-Quality Materials

This work reports the effects of moisture content and particle size distribution on the gasification performance of hybrid poplar, corn stover and municipal solid wastes (MSW) in a modular plasma-gasification system. The MSW tested includes construction wastes, plastics and refuse derived fuels. To date, there has been very little data in the literature to support the feasibility of MSW gasification. In addition, while gasification has been demonstrated at large scale (over 200 tons per day), it is unknown whether smaller scale (2-40 tons per day) deployment of gasification technologies will be economical. It is at these scales where many of the applications of MSW gasification will reside since there are relatively few areas in the US with large amounts of MSW available. The presented work may serve as a basis for techno-economic analyses and scale up research.

Hybrid poplar was tested at 9 different conditions using a 3² matrix with respect to particle size and moisture content. Corn stover was tested at varying particle sizes, and MSW were tested at 4-6 mm particle size and â??as isâ?? moisture. In addition, the different samples were air classified and assigned a measure of buoyancy to delineate between particle size affects and buoyancy. Inorganic and organic mass balances were done for the initial feedstock materials and the resulting slag, when possible, using ICP and CHNO proximate/ultimate analyses. CO₂, CO and H₂ production were measured inline and from collected product gas samples. The presence of other hydrocarbons was tested using GC-MS, but none were detected. Results suggest that hybrid poplar produced syn gas between 30 and 40% H₂, and between 35 and 45% CO, with some dependency on formatting conditions. Less than 2% of the material was recovered as slag, and it generally consisted of silica and alkali and alkaline earth metals. Initial testing of the corn stover and MSW suggest successful gasification, but that formatting plays a more critical role in MSW gasification than in hybrid poplar gasification.