Biomass gasification cleanup

The increased efficiency in IGCC systems translates into environmental benefits because emissions per unit energy produced are lower. This includes CO, NOx, SOx, C02, and particulates. NOx and SOx emissions are inherently lower in biomass IGCC systems because biomass fuels tend to have low N and S contents to start with, and gas cleanup and conditioning in biomass gasification systems removes these impurities before the syngas is combusted in the gas turbine. The same is true for particulates. C02 emissions are effectively zero, because biomass is a renewable fuel. 

Caballero, M. A., Cotella, J., Aznar, M. P., and Gil, J., Biomass gasification with air in fluidized bed. Hot gas cleanup with selected commercial and full-size nickel-based catalysts. Industrial Eng Chem Res 2000, 39 (5), 1143-1154. 

Virginie, M., Courson, C., Niznansky, D. et al. (2010) Characterization and reactivity in toluene reforming of a Fe/olivine catalyst designed for gas cleanup in biomass gasification. Applied Catalysis B Environmental, 101, 90-100. 

Sulfur in the biomass feedstock can be converted to hydrogen sulfide or sulfur oxides during gasification. Wood typically contains less than 0.1% sulfur by weight, and herbaceous crops may contain 0.3 to 0.4%. Some feedstocks such as refuse-derived fuel (RDF) may contain 1% or more, approximately the same as bituminous coal. As a result of the low levels of sulfur in the biomass, the concentrations of H2S and SOx levels in the product gases are below those requiring cleanup in most applications. 

International Energy Agency (1991). Task VII, Biomass Conversion, Activity 4, Thermal Gasification, Summary Report for Hot-Gas Cleanup, Compiled by Institute of Gas Technology. Institute of Gas Technology, Chicago, December. 

Pressurised gasification of biomass and fossil fuels in fluidised bed gasifiers, hot gas cleanup using ceramic filters and pressurised product gas combustion... 

The test rig at IVD (50 kWth) and the Delft PDU (1.5 MWth) were operated successfully with respect to pressurised gasification, high temperature gas cleanup and combustion of biomass (wood and Miscanthus) and brown coal derived LCV gas. 

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