Grant: Strategic Projects - Group

Concerns on local air quality, global warming and the depletion of non-renewable energy resources have led to the enactment of progressively strict regulations requiring efficient and clean burning fuels. In 2002, 527 million tonnes of CO2 equivalent greenhouse gases were emitted from combustion sources, representing 72% overall greenhouse gas emissions in Canada. To enable a gradual transition of Canadian fossil fuel economy to renewable fuel economy, efficient, economically viable and environmentally sound renewable energy systems need to be developed. Forest and agricultural biomass residues are abundantly available in Canada, especially in British Columbia and Quebec. Due to its low density and low heating value, raw biomass needs to be converted to high energy density liquid fuels. Among the many thermal chemical conversion pathways, gasification has been considered as one of the most promising pathways to convert bulk solids biomass to an intermediate syngas which is then further converted to biofuels such as biodiesel, bioethanol or dimethyl ether (DME) or chemicals. Low calorific value syngas has been produced by gasification in an air or air/ steam gasifier. The produced syngas, however, is not suitable for conversion to liquid fuels because of its high nitrogen content. In this proposed project, researchers at the UBC's Clean Energy Research Centre teams up with Highbury to develop an autothermal dual fluidized bed steam gasification process for the production of medium to high quality syngas which, after cleanup, can be further converted to liquid biofuels. A dual bed gasification unit will be commissioned by upgrading an existing circulating fluidized bed air/steam gasifier. In the new dual gasifier system, steam gasification takes place in one reactor while combustion of biochar takes place in a separate air combustor, with the heat released from the char combustion supplied to the steam gasifier via the circulating solids heat carrier. Catalyst particles will be added to the gasifier to minimize the tar formation, while catalytic tar control of syngas will also be examined.