Multi-stage packed gas washer - with separate liquor recycle to each stage and fresh liquor feed to topmost

摘要

Process for washing dust from gases uses a wash liquor recycling round a packed column section of which there are two or more one above the other, gas flowing vertically upward. Each section has separate liquor draw off and recycle and liquor cascades downwards from one section to the next, fresh liquor being fed in at the top. This is sprayed upwards onto a knitted mesh pad above the top section. Liquor is collected by draw off into vessels below. Liquor from the upper section cascades over a baffle into the vessel for the lower section. A droplet disentrainer in the form of wet film separator is mounted on the top. To scrub dust out of gas streams. Co-current roasting of gas streams for dust removal has been shown to save wash liquor. However it is limited to processes in which only slight gravity varus-occur as this effects the efficiency. By using several stages in counter-current with recycle, the disadvantages are overcome and a marked sawing of liquor obtained.