The acid mist waste gas is introduced into the PP spray tower through the air pipe, and passes through the packing layer. The waste gas and sodium hydroxide absorption liquid are in full contact with the gas-liquid two-phase absorption and neutralization reaction. After being discharged into the atmosphere by the fan. The absorption liquid is sprayed down on the top of the tower after being pressurized by a water pump at the bottom of the tower, and then returned to the bottom of the tower for recycling. The purified acid mist exhaust gas meets the emission requirements of the local emission standards of Guangdong Province, which is lower than the national emission standards.