Method and system of producing and utilizing fuel gases, in particular gases obtained from biomasses or refuse

摘要

A method of obtaining fuel gases from a gasifier, which gases are then burned in a diesel engine and so converted into useful energy. According to the method, as opposed to total purification of the fuel gases from the gasifier to eliminate the condensable substances (tars), the fuel gases are simply dedusted by means of a cyclone upstream from the diesel engine; and the dedusted, compressed fuel gases are then cracked in a reactor upstream from the diesel engine. The gases may be compressed in the gasifier itself, or after gasification, before or after tar cracking. The reactor is a fixed-bed type for only eliminating from the dedusted gases the higher-molecular-weight condensable substances (over 900 daltons), i.e. those with a higher condensation temperature (over 200°C). Finally, the gases from the cracking reactor are cooled to a temperature Ta (about 250°C) higher than the condensation temperature of the residual tars, and are supplied at that temperature to the diesel engine separately from the combustion air.