Flue gas cleaning using foam-forming reactant - involves subsequent foam destruction and separate collection of removed contaminants

摘要

A gas cleaning process esp. for flue gases, involves contacting a foam-forming reactant with the gas in a reaction chamber, destroying the foam after reaction, separately collecting recovered reactant and sludge and releasing the cleaned gas. When cleaning gases at below 60 deg. C, (a) foam destruction is carried out in the reaction chamber to form a dense foam and an underlying reactant layer mixed with water and gases; (b) the dense foam and surface sludge are withdrawn from the reaction chamber by suction and are temporarily stored for gravity sepn., and (c) material layer-spen. is carried out in a settling phase, the individualy layers being successively sepd. When the gases are at above 60 deg. C the settled sludge is dried in a dryer by stepwise vertically downward transport of the sludge in contact with dirty gas fed to the dryer. Also claimed is a plant for carrying out the process, including a reaction chamber contg. rotating rolls for contacting the gases with the reactant. ADVANTAGE - The process allows sepn. of the materials removed from the gases