The acid waste gas purification process is: acid gas – three-stage alkali spray – chimney discharge.
(1) Neutralization treatment of sulfuric acid mist: Generally, a sodium carbonate (Na2CO3) alkaline solution having a mass fraction of 10% and a pH of 10 can be used for neutralization treatment of sulfuric acid mist.
(2) Neutralization treatment of hydrochloric acid mist: Neutralization treatment can be carried out with a low concentration alkali solution (NaOH). Generall, a 2%-5% sodium hydroxide solution is used as the absorption liquid.
(3) Neutralization treatment of hydrofluoric acid mist: Neutralization treatment may be carried out by mixing 5% Na2CO3 and 3% NaOH solution.