Coal gasification environmental impacts

Coal used in power stations has the potential to be partly replaced by fuels derived from pre-treated plastics and paper waste, reducing both dependency on fossil fuels and reliance on landfill. APME reports on a project in the Netherlands which it co-sponsored to develop a substitute fuel from plastics. The environmental assessment of the project compared the environmental impacts of coal substitution with other plastics recovery methods, including gasification in feedstock recycling and energy recovery from plastics waste in cement kilns. The study also compared coal substitution with the generation of power from burning biomass. 

The Vision 21 program is focused on new concepts for coal-based energy production where modular plants could be configured to produce a variety of fuels and chemicals depending on market needs with virtually no environmental impact outside the plant s footprint. Membranes would be used to separate oxygen from air for the gasification process and to separate hydrogen and carbon dioxide from coal gas. 

A similar opportunity exists for the public utility industry in the potential of LBG and MBG. The reduced environmental impact of a coal gasification plant which produces a perfectly clean fuel equivalent to natural gas, compared to direct combustion of coal may allow increased use of coal in areas where increased pollutant emission is barred. As these PSD areas increase in number, the advantages of coal gasification become more apparent. The potential of more efficient combined cycle generation systems which can be used with coal-derived gases is an added factor for implementing coal gasification. 

None of these current processes has a distinct advantage over the other two in all situations of coal gasification. However, we believe that the Winkler is best suited for the production of methanol because it yields a clean gas with a low inerts content. Other advantages include the plant s low environmental impact, the minimal coal preparation required and the simple construction of the Winkler gasifier. 

Williams, A., et al. Combustion and Gasification of Coal New brk Taylor Sc Francis, 2000. Provides an overview of coal combustion and gasification with special attention to the properties of coal, combustion mechanism of coal, combustion in fluidized beds, the gasification process, industrial applications, and environmental impact. 

History. Public Service of Indiana (PSI) is a major electric utility located in the state of Indiana. PSI is severely impacted by the SO2 reduction provisions of the Clean Air Act Amendment (CAAA) of 1990 due to it s large use of local high sulfur Indiana coals in older coal-fired units with no existing SO controls. However, there are special provisions in the CAAA for coal gasification repowerin. These provisions are discussed in detail in the Environmental Aspects, Section 4, of this report. Briefly, coal gasification repowering extends the Phase I SO2 emission allowances to the end of 1999 for the specific units repowered. The much lower Phase II allowances do not become effective until the end of 2003 for the specific units repowered. 

D. Simbeck, "Town Gas and Coal Gasification in China. Presented at Workshop on the Efficiency and Environmental Impact of Coal Use in China, Beijing, China, September 10-13, 1991. 

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