Construction and Operating Principle: Waste gas is fed into absorber tower at its bottom, and comes into contact with the acidic/basic absorbent liquid in a countercurrent flow direction. Then, the absorption of contaminative compositions of waste gas takes place through gas-liquid contract neutralization. The water resulted from such absorption is separated from clean gas by water eliminating blanks. At last, the clean gas is emitted into the atmosphere Application：Control and treatment of acidic/basic waste gases from bolt/screw manufactories, electroplating industry, heat treatment processing industry.