Conversion of forest residues to a methane-rich gas in a high-throughput gasifier

Research was conducted in a process research unit to develop an entrained bed gasifier which is supplied heat by recirculating a stream of sand between a separate combustion vessel and the gasifier. The char remaining after gasification of the wood provides the fuel for the combustor. The research program was conducted in two phases. In the first phase, a 6 in. I.D. gasifier was used to establish the feasibility of the concept for a wide variety of biomass feeds. The second phase of the program was conducted with a 10 in. I.D. gasifier, and a fully automated feeder system, to evaluate gasifier performance at very high feed rates. The experimental results were used to develop design parameters and detailed energy and material balances for a conceptual plant. A preliminary cost analysis is presented in the report based on the conceptual design. 5 refs., 24 figs., 13 tabs.