Processes and Products Based on Coal

The processes of coal utilization can be divided into four areas, pyrolysis, combustion, gasification to syngas, and liquefaction with high-pressure hydrogen. 

Coal Pyrolysis Pyrolysis is the chemical decomposition by heating in the absence of oxygen or of any other reagent, whereby the volatile constituents of the coal -water, gases like H2, CO, and CO2, and hydrocarbons ranging from methane to tar - are driven off. Pyrolysis is not only important for coke making, but also as the 

Coal Combustion and Electricity Production World coal consumption is about 3.3 billion tonnes oil equivalent annually (2008), of which about 75% is used for to generate electricity. Coal currently supplies about 39% of the world s electricity, 4% based on lignite and 35% based on black (hard) coal (RWE, 2005). For electricity generation, coal is usually pulverized and burned in a furnace with a boiler to produce steam that is used in turbines to create electricity with about 40% efficiency for the entire process. In addition to electricity production, 13% of the global coal production is burned in the domestic and non-metallic industry, for example, for cement production. 

Coal Gasification The current high price of oil and gas has lead to an increased interest in coal gasification. 

Raw Materials, Products, Environmental AspeUs, and Costs of Chemical Technologf 

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Figure 5.1.27 Processes and products based on coal. Adapted from Benthaus et al. (1978).

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