A recycling process of electroplating wastewater

Abstract

The invention discloses a process for recycling electroplating wastewater. The process comprises the following steps: (1) carrying out advanced-treatment pretreatment on the electroplating wastewater; (2) carrying out advanced-treatment aftertreatment on discharge water; (3) enabling treated wastewater to flow through filter paper so as to filter the treated wastewater; (4) pumping the wastewater into reverse-osmosis equipment; (5) carrying out detecting. By adopting the wastewater recycling process disclosed by the invention, requirements of the reverse-osmosis equipment on influent water quality can be met, the water quality of recycled water is stable, normal operation for the reverse-osmosis equipment can be ensured, the reverse-osmosis equipment can normally work for 10 months and even longer than 1 year, and meanwhile, the wastewater of a high-pressure side can be discharged after reaching standard.

Description

technical field [0001] The invention relates to a waste water utilization method, in particular to a recycling process of electroplating waste water. Background technique [0002] In industrially developed countries, reused sewage (or reclaimed water) has become an important second water source, which better solves the contradictions between industrial development and water resource shortage, industrial development and water environment pollution. For example, although the water consumption in the United States increased by 138% in 2000 compared with 1975, the water intake decreased by 8.8%. [0003] At present, in terms of the reuse of electroplating wastewater in my country, after the electroplating wastewater is precipitated and separated from the sludge by general chemical methods, the supernatant water is filtered through a carbon filter or sand filter device, and then enters the reverse osmosis equipment, and the low-pressure side returns to the reverse osmosis equipme...

AI Technical Summary

Problems solved by technology

Sometimes due to changes in the pH of the sedimentation tank, the sludge will be redissolved in the supernatant water, commonly known as reverse bottom, and the water quality will be worse

If the above-mentioned wastewater is treated by carbon filtration, it will enter the reverse osmosis equipment, and the transmittance of the low-pressure side is less than 30%. If the pressure is increased, when the transmittance exceeds 30%, heavy metals will be detected in the discharge water of the low-pressure side, which cannot be reused.

At the same time, the service life of the reverse osmosis membrane is only 2 months. The reason is that the reverse osmosis membrane is invalidated by the swelling and erosion of electroplating additives, and the discharged water cannot be reused.

Therefore, not only the reuse cost is high, but also the reuse effect is poor

So in fact, there is no success in reusing

[0006] 2. If the discharge water from the low-pressure side can be reused, and the harmful and toxic substances contained in the wastewater are concentrated in the discharge water from the high-pressure side, they are generally discharged directly. Although part of the wastewater can be reused and the amount of discharged water is reduced, it is really harmful and toxic. Pollutants have not been reduced, and the goal of emission reduction is still not achieved

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