(623b) Biomass Gasification in a Stoker Gasifier

As a consequence of increasing energy costs and a push towards carbon-neutral energy sources, the forest products industry is interested in minimizing its use of fossil fuels and increasing energy production from biomass. One solution is to gasify biomass to create a combustible gas that could be used to displace natural gas or oil in boilers and lime kilns. The biomass gasifier should be simple and robust, with low capital and operating expenses. Detroit Stoker Company has over 100 years experience with biomass combustion and has many stokers installed at forest products facilities throughout the world. If a stoker is operated under reducing conditions (stoichiometric ratio < 1.0), it effectively becomes a gasifier and could conceivably offer a low cost gasification solution for the forest products industry. In the study presented here, Detroit Stoker Company and the University of Utah performed a first-of-a-kind gasification campaign using a 300 kWth pilot stoker facility at the University of Utah. Results indicate that a stoker-type gasifier can produce a quality producer gas (synthesis gas) while maintaining good heat release from the bed. In this presentation, overall performance of a stoker gasifier is discussed and data relating to system performance and product gas quality is presented.