Grant: Collaborative Research and Development Grants

A two pronged research plan is proposed by researchers at the University of Saskatchewan in partnership with SaskPower, PAMI, Rentech Inc. and Saskatchewan Ministry of Agriculture ADF program. This project will develop moving bed torrefaction technology for use with locally produced biomass including hybrid willow and wheat straw, and examine the effect of torrefaction of biomass prior to gasification on the syngas quality and gasifier efficiency. Torrefaction is a thermal treatment process for biomass which removes moisture, improves storage and grinding characteristics and increases energy density; the resultant char can be co-fired with coal at ratios up to 40%. A unique torrefaction process concept shall be implemented through design, fabrication and testing of a 1-5 kg/hr pilot scale continuous torrefaction unit (CTU). The CTU will incorporate moving bed heating and will be used to assess a segmented heating system, product spectral analysis, and fuzzy logic control of the process. It is expected that these innovations shall produce torrefaction gases with enhanced combustion value, and provide real-time measurement and control of biomass conversion. Upon commissioning of the CTU, it will be evaluated with local biomass feedstocks. It has been hypothesized that torrefaction of gasifier feedstocks will reduce expected syngas tars, thus lowering syngas cleanup cost and increasing the viability of subsequent conversion to liquid fuels such as biodiesel and bio-jet fuel. The pilot-scale fluidized bed gasifier in the University of Saskatchewan fluidization lab will be used to study the gasification of local biomass feedstocks. This work shall undertake quantitative measurement of syngas tar species by molecular beam mass spectrometry, specifically analyzing this from compositions affected by torrefaction. Though torrefaction has been shown to increase gasifier efficiency, tar composition for gasification of these biomass sources after torrefaction has never been undertaken; this project will thus provide important data for using these sources as feedstock for liquid fuels production.