Fluidized-Bed Gasification Processes

Kurkela, E., Formation and Removal of Biomass Derived Contaminants in Fluidized-Bed Gasification Processes, VTT Publications 287, 1996, Espoo. 

In Great Britain, the Imperial Chemical Industries, Ltd., has developed a fluidized coal gasification process (32) using combustion of part of the fuel with air to supply the heat necessary for the endothermic steam-carbon reaction. This procedure is divided into three steps carbonization, air-blowing, and steam-blowing. The first and third steps operate with fluidized beds, and the second with a dilute suspension. Powdered coal is fed into the carbonization vessel, where it is heated by combustion of some of the carbonization gases. The powdered char is blown into a feed hopper connected with the air-... 

Kojima, T., Assavadakom, P. Furusawa, T. (1993).Measurement and evaluation of gasification kinetics of sawdust char with steam in an experimental fluidized bed. Fuel Processing Technology, Vol. 36, pp. 201-207. 

Aromatic hydrocarbons occur as by-products only in fixed-bed processes, since the coal does not undergo a carbonization stage in fluidized or entrained bed gasification processes. As a result of the high reaction temperatures, all volatile hydrocarbons are rapidly converted to gas. 

Matsuoka, K., Hosokai, S., Kuramoto, K., Suzuki, Y. (2013). Enhancement of coal char gasification using a pyrolyzer-gasifier isolated circulating fluidized bed gasification system. Fuel Process Technology, 109, 43—48. 

Carbonaceous fuels are used throughout the world as major energy sources. They exist primarily in solid forms, or heavy liquid forms, containing significant process and environmental contaminants compared to cleaner fuels such as natural gas. Coals and biomass fuels are two of the many carbonaceous fuel types that can be effectively processed in fluidized bed reactors, and they are currently of great industrial interest for fluidized bed gasification and combustion. 

Kaewluan S, Pipatmanomai S (2011) Gasification of high moisture rubber woodchip with rubber waste in a bubbling fluidized bed. Fuel Process Technol 92 671-677... 

Dong L, Xu G, Suda T (2010) Murakami potential approaches to improve gasification of high water content biomass rich in cellulose in dual fluidized bed. Fuel Process Technol 91 882-888... 

Haldipur, G., Schmidt, D and Smith, K. (1988) A 50-month gasifier mechanistic study and downstream unit process development program for the pressurized ash-agglomerating fluidized-bed gasification system, final report volume II. Technical Report, KRW Energy Systems Inc. 

A 50-Month Gasifier Mechanistic Study and Downstream Unit Process Development Program for the Pressurized Ash-Agglomerating Fluidized-Bed Gasification System, Final Report Volume II. Tech. Rep., KRW Energy Systems Inc. 

The description given apphes to DR processes that are based on the use of gaseous reductants ia shaft furnaces, batch retorts, and fluidized beds. In the processes that use sohd reductants, eg, coal (qv), the reduction is accomphshed to a minor extent first by volatiles and reduciag gases that are released as the coal is heated and then by CO that is formed by gasification of fixed carbon contained ia the coal char with CO2. Reductioa by sohd carboa and coal volatiles ia kilns is insignificant. 

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