The invention discloses an
electroplating wastewater treating and recycling process and
system which are designed especially for solving the problems that the cost of the process for pretreating the
electroplating wastewater is high, the
sludge quantity is high, and the
recovery rate of a film
system is low in an existing chemical method. The
electroplating wastewater recycling process comprises the following steps: adsorbing
nickel-containing wastewater through resin to recover
nickel salt; treating
pickling waste liquid by
electrodialysis to recover acid and then mixing with acid-alkali wastewater; transferring into an adjusting tank together with
cyanide-containing wastewater subjected to alkaline second-stage
cyanide breaking; enabling the
water quality and volume to be uniform; transferring into a neutralizing tank; adding alkali to adjust pH (Potential of
Hydrogen) to reach neutral value; then feeding into a film treating
system in the combination of first-stage
nanofiltration and second-stage
reverse osmosis, wherein the water produced by
reverse osmosis is recovered into an electroplating workshop, and the concentrated water produced by
nanofiltration is recovered into the neutralizing tank; performing second-stage
reverse osmosis on the concentrated water subjected to first-stage reverse
osmosis; and transferring the concentrated water subjected to second-stage reverse
osmosis into an efficient
evaporator to evaporate. By adopting the process and system, the
nickel and acid resources can be effectively recovered, the
recovery rate of wastewater can be greatly raised, and the operation stability of the film system also can be greatly improved.