Process for the elimination of NOx from flue gases

摘要

Process for the elimination of NOx from flue gases by selective catalytic reduction with addition of ammonia after flue gas cooling and dedusting have been carried out, the dedusted flue gases, prior to the catalytic reduction, being heated by heat exchange with a heat transport medium in a first heat exchange stage and, after catalytic reduction has been carried out, being cooled again in a second heat exchange stage by heat exchange with the heat transport medium circulating through the two heat exchange stages and the temperature of the flue gases being increased further on the path from the first to the second heat exchange stage and/or the temperature of the heat transport medium being increased further on the path from the second to the first heat exchange stage by supply of external heat and the temperature of the flue gases after the second heat exchange stage and/or the temperature of the heat transport medium on the path from the first to the second heat exchange stage being decreased again by removal of heat to the outside.