Investigation of a Filter as a Combined Dust Removal Unit and Chemical Reactor

Bag filters and also granular filters are frequently used to remove dust particles from gas streams. Moreover bag filters may also act as chemical reactors when the penetrating gas reacts with the filter cake, the filter cloth or in the granular filter bed. The influence of the filter operation on the features of this filter as a chemical reactor is investigated in a pilot plant of a flue gas cleaning process. Based on macrocopically available data, a mathematical model is developed that accounts for the filter cake growth, the residence time of the solid particles on the filter cloth, and the chemical reaction in the filter cake. The reactions are investigated by means of a laboratory fixed bed reactor. Special attention is paid on the operation stability of filters.