Zero-discharge treatment process for electroplating wastewater

The invention belongs to the technical field of sewage treatment, and particularly relates to a zero-discharge treatment process for electroplating wastewater. The technical key points are as follows: the evaporation adopts linkage of two-effect three-stage falling film evaporation and a four-stage forced circulation evaporator, and adopts two-stage steam compression; the electroplating wastewater is a mixture of metal cations Zn < 2 + >, Cu < 2 + >, Ni < 2 + >, Cr < 6 + > and Cd < 2 + > and anion cyanide; the pretreatment comprises cyanogen breaking treatment, and specifically, the comprehensive electroplating wastewater is subjected to cyanogen breaking treatment by adopting a SO2-air method. According to the invention, SO2-air method cyanogen breaking and two-effect three-stage falling film evaporation are combined, and the heating temperature is adjusted according to the salt concentration of the material, so that the technical purposes of energy conservation and high efficiency are achieved, and the MVR