Compact, catalytic flue gas cleaning unit tackling widely-varying flowrates and temperatures from smaller combustion plants

摘要

Cleaning of flue gases flowing at differing velocities and/or temperatures, is accomplished by a new method. The gas is cooled in a recuperative heat exchanger, preheating air for combustion. In a second cooling stage, achieving a set temperature range, an economiser (waste gas heat exchanger) raises the temperature of a fluid. The flow is adjusted to a set volumetric rate, using a controlled bypass. The recombined waste gases then pass through a static mixer, making the temperature uniform. Flow continues through a conventional catalyst section, at the outlet of which, the gases pass a further gas/fluid exchanger (second economiser), reducing the temperature of the cleaned waste gases. Heat from the common fluid circuit is available for application. Also claimed is the corresponding plant.