Assessment of large-scale biomass gasification systems for less-developed countries

This state-of-the-art report evaluates large-scale biomass gasification systems both economically and technically and analyses their potential applications in developing countries. After a discussion of biomass feedstock types, handling, and preparation, the authors describe various types of gasifiers available (fixed-bed updraft and downdraft, fluid-bed, and entrained-bed) and their current applications. Gasification chemistry, advanced gasification systems, and gas cleaning are also considered. Next, the use of fuel gas from biomass for steam power production, other fired equipment, internal combustion engines for power production, gas turbine cycles, synthesis of methanol and other liquid fuels, and synthesis of ammonia and other chemicals, is discussed. The environmental impacts of biomass gasification are reviewed. The authors conclude that availability of sufficient feed materials is essential for large-scale biomass gasification in developing countries. The most promising applications are: (1) rural electrification using air-blown biomass gasifiers and diesel generators; (2) retrofitting existing oil and gas fired equipment in various industries, particularly in agricultural processing plants; and (3) producing ammonia-based fertilizers from biomass-derived synthesis gas.