Method and equipment for recovering acid-washed coal fluorine-containing waste liquid

The invention provides a method and equipment for recovering acid-washed coal fluorine-containing waste liquid. The method comprises the following steps: concentrating and crystallizing the fluorine-containing waste liquid, and then carrying out filtering to obtain mixed acid liquid and crystallized solid; reacting the crystallized solid with concentrated sulfuric acid to obtain hydrogen fluoridegas, sulfate and a silicon-containing intermediate; outputting the sulfate as a byproduct; absorbing and reacting the silicon-containing intermediate with the mixed acid solution to improve the concentration of the mixed acid solution and obtain a silicon dioxide precipitate; after separating silicon dioxide, adding concentrated sulfuric acid to react to obtain hydrogen fluoride gas and dilute sulfuric acid; and outputting the silicon dioxide as a byproduct. The method solves the problem of cyclic utilization of the fluorine-containing waste liquid in the coal acid-washing process, reduces environmental pollution, red