Bed Gasification Processes

The gasification plant is equipped with two Texaco gasifiers, each capable of producing all of the synthesis gas required for operation of the complex. Eastman chose an entrained-bed gasification process for the Chemicals from Coal project because of three attractive features. The product gas composition using locally available coal is particularly suitable for production of the desired chemicals. Also, the process has excellent environmental performance and generates no Hquids or tars. EinaHy, the process can be operated at the elevated pressure required for the downstream chemical plants. 

The Circulating Fluidtsed-Bed gasification process was not as sensitive to ash sintering as the small-scale bubbling fluidised-bed reactor. The amount of potassium chloride increased from bottom ash to hot filter dust. 

Kurkela E, 1996) Formation and removal of biomass-derived contaminants in fluidised-bed gasification processes. VTT publications report No. 287, VTT,... 

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. 

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

Matsumura, Y. Minowa, T., Fundamental design of a continuous biomass gasification process using a supercritical water fluidized bed. Journal of Hydrogen Energy 2004, 29, 701. 

CAFB [Chemically active fluidized-bed] A coal-gasification process intended for producing gas for power generation. Coal particles are injected into a shallow bed of lime particles that trap the sulfur dioxide. The bed particles are regenerated in a second fluidized bed, releasing the sulfur dioxide. Developed in the 1970s by the Esso Petroleum Company, UK, but not commercialized. 

C02 Acceptor A fluidized bed coal gasification process in which the heat is provided by the exothermic reaction of carbon dioxide with calcium oxide. Developed by the Conoco Coal Development Company in the 1970s. 

Coalcon A coal gasification process using a fluidized bed operated with hydrogen. Developed by Union Carbide Corporation and the Chemical Construction Company, based on work on liquid-phase hydrogenation completed by Union Carbide in the 1950s. A 20-ton per day pilot plant was operated in the 1960s, but a planned larger demonstration plant was abandoned because of cost. 

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