Feedstock Blending in Indirectly Heated Gasifier/Liquifiers

Abstract

Co-utilization of solid fuels with combustion turbines (CTs) can be accomplished by blending feedstocks in indirectly heated gasifier/liquifiers (IHG/L), Blending could improve the quality and yields of gaseous and liquid fuel outputs and, with gas clean-up (GCU) or liquid distillation, serve valuable societal functions. Gas yields vs. temperature, time and other variables have been obtained using batch fed and continuous fed laboratory scale IHG/Ls using particle sizes suitable for commercial systems. The rates of solids to gas/liquid conversion are mainly dependent upon the heat transfer and diffusion coefficients of the biomass rather than the rate constants for chemical decomposition. Phenomenological engineering formulas are developed for use with biomass that can be treated as a blend of hemicellulose, cellulose and lignin. The main immediate goals are to develop: 1) laboratory scale process development units (PDUs) that can help anticipate results with commercial IHG/L systems, 2) predictive models for estimating gaseous, liquid and char yields when various blends of biomass and other domestic fuels are processed in IHG/Ls and 3) applications of IHG-GCU-CT systems that could drive technology development during periods of low oil and natural gas prices.