Das Projekt "Coal gasification - waste heat utilization" wird vom Umweltbundesamt gefördert und von Krupp Koppers durchgeführt. Objective: Development and test operation of a new waste utilization system (radiation boiler) and of further new components for pressurized entrained flow gasification (PRENFLO). The new components besides the radiation boiler were a candle filter (dry dedusting of PRENFLO raw gas), a fly ash recycle system, a catalytic COS hydrolysis and a raw gas desulfurization system (MDEA process). General Information: The partial oxidation of solid fuels according to the entrained-flow principle (PRENFLO process) is an exothermic process, approx. 20 per cent of the gross calorific value of the fuel being converted into sensible heat. Utilization of this large quantity of heat released is indispensible for the energetically optimum of the PRENFLO process in industrial-scale applications. The raw gas leaves the gasifier at a temperature of approx. 1400 deg. C, highly laden - about 160 g/m3 (24 bar) with small molten or doughy ash particles. The heat utilization concept realized to date at Krupp Koppers comprises the cooling of raw gas at the outlet of the gasifier with quench gas to temperatures of less than 1000 deg. C resulting in higher heat losses at temperatures below 250 deg. C. The hot gas quenching can be avoided by using the new waste heat utilization system for dust-laden PRENFLO raw gas with high optical density. It is based on a radiation boiler with built-in heat exchange elements, the arrangement of which takes account of the temperature and flow profile of the hot raw gas leaving the reactor. Results from the operation of a 48 t/d PRENFLO plant with regard to slag separation in the gasifier, effectiveness of mechanical dedusting devices, decoupling of radiation boiler from gasifier to take account of the vibrational properties (mechanical cleaning device for heat exchangers), and theoretical investigations on heat exchange for optically dense fluids indicated the possibilities of preventing energy losses by quench gas cooling of raw gas. Optimization of the system with regard to the spacing of the heat exchange elements, the cleaning and the geometry of the system result in lower overall height and anticipate efficiency improvements if the system is applied in a CC-power plant. The dry dedusting of PRENFLO gas allows fly ash recycling to the gasifier, thereby a total slagging of the coal ash and a total carbon conversion can be achieved. A high effective filtering system reduces heat losses with the raw gas, when hot dedusted gas from the filter is recycled as quench gas. A candle filter and a pneumatic fly ash recycle system was planned, built and tested. For the desulfurization of the PRENFLO gas a catalytic COS hydrolysis (conversion of COS to H2S) and a H2S absorber (MDEA process) were installed in the test plant to proof the reliability of these process stages for PRENFLO gas in a wide range of operating conditions and to take account of the gas and solid traces in the gas to be treated. Testing and optimization of the waste heat...