The gasification of coal has now been practised on a commercial scale for a long time. In recent years, however, intensive efforts have been made to develop the gasification technology further in order to meet today's technical and economic requirements. Two advanced gasification processes have attained industrial maturity, together covering the entire range of potential feedstocks:. The TEXACO gasification process is an entrained-flow partial-oxidation process using pumpable feedstock. Four commercial-scale coal gasification plants applying this process are in operation worldwide, two further units being under construction. The first TEXACO coal gasification plant in Europe, Synthesegasanlage Ruhr (SAR), took up operation in 1986 at Oberhausen/Fed. Rep. of Germany. The pressurized RHEINBRAUN High-Temperature Winkler (HTW) process has been developed on the basis of the conventional atmospheric Winkler fluidized-bed gasification process. In early 1986, a commercial-scale HTW demonstration plant for the gasification of brown coal went on stream in the Fed. Rep. of Germany. A second commercial-scale HTW gasification plant was started up at Oulu/Finland in 1988 using peat as a feedstock for synthesis gas generation. The implementation of this plant indicates a trend in the further development of solid fuel gasification towards a diversification of feedstocks. The fluidized-bed technology applying the HTW process is also well suited for processing wood and biomass as well as reactive types of bituminous coal. Owing to its specific process characteristics, the fluidized-bed principle can also be used for the gasification of low-grade coal types such as high-ash coal and brown coal with a high salt content. The application of the gasification technology for waste processing has been studied on a theoretical basis. Nearly all types of hard coal as well as heavy residues and fuel oils can be processed by the entrained-flow technology applying the TEXACO-process. Regarding the products obtained from gasification, a tendency towards diversification can be observed, too: Whereas the predominant product from existing coal gasification plants is synthesis gas for chemical applications, the production of fuel gas is gaining importance for the future. The integration of a gasification step in a combined-cycle process is of special interest, this type of power station offering decisive advantages regarding emission levels, efficiency and production costs. Another interesting alternative is the application of solid fuel gasification for the combined production of chemicals, heat and power, resulting in high overall thermal efficiencies for energy conversion. The aspects outlined above are illustrated by examples and substantiated by facts and figures. © 1990.
