Treatment method of acid-containing acidic wastewater in crude selenium production process

The invention discloses a method for treating acid-containing acidic wastewater in a crude selenium production process, which comprises the following steps: adding a reducing agent into the acid-containing acidic wastewater, and carrying out oxidation-reduction reaction to obtain copper tellurium slag and decoppered liquid; detecting the mass concentration of chloride ions in the copper-removed liquid; and when the mass concentration of the chloride ions in the copper-removed liquid is 5-20 g/L, returning the copper-removed liquid to the chlorination and selenium removal treatment process to be used as leaching acid and a chloride ion additive to perform chlorination and selenium removal treatment on the copper-removed sludge. According to the method, the reducing agent is added into the acid-containing acidic wastewater to reduce the copper and the tellurium, so that the copper and the tellurium in the acid-containing acidic wastewater are recovered, and the copper-removed liquid is returned to the chlorinat