Treatment method and system of nickel-containing wastewater conforming to Water Pollutant Table III Discharge Standard

Abstract

The invention discloses a treatment method and system of nickel-containing wastewater conforming to Water Pollutant Table III Discharge Standard. The method comprises the following steps: sending nickel-containing wastewater into a wastewater collecting tank, and pumping into a nickel reaction tank by a water pump to perform pretreatment; regulating the pH value, adding a heavy metal capturing agent, thoroughly mixing to react, adding a coagulant aid and a flocculant, sufficiently and uniformly stirring, and standing to precipitate or sending into a solid-liquid separation device; sending into an intermediate water tank, and adding a sulfuric acid solution to regulate the pH value to 7-8; and pumping water in the intermediate water tank into a heavy metal scavenger by a filtering machine, and treating to achieve the Table III Limit Discharge Standard. The method and system solve the problem that the existing nickel-containing wastewater in electroplating industry can not satisfy the Table III Discharge Standard in Water Pollutant Special Limits, so that the electroplating nickel-containing wastewater can stably satisfy the discharge requirements.

Description

technical field [0001] The present invention belongs to the field of sewage treatment, and specifically relates to a treatment method and system for nickel-containing waste water that meets the discharge standards of Table 3 of Water Pollutants, meets the discharge standards of Table 3 of "Special Limits of Water Pollutants", and can be used in the electroplating industry Treatment of nickel-containing wastewater. Background technique [0002] Electroplating is to use chromium, zinc, nickel, cadmium, copper, etc. to coat a metal protective layer on the surface of the workpiece to enhance the corrosion resistance and aesthetics of metal or plastic products. Electroplating wastewater mainly comes from pre-plating wastewater, coating rinsing water, coating post-treatment wastewater and electroplating waste liquid. [0003] Heavy metal ions are highly toxic substances that are carcinogenic, teratogenic or mutagenic. If a large amount of electroplating wastewater containing heav...

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Problems solved by technology

[0008] China Patent No. 201210032729.8, the patent name is "Comprehensive Electroplating Wastewater Treatment Method", which is a treatment method based on the combination of chemical process and biochemical process, but it still cannot meet the discharge of Table 3 of "Special Limits of Water Pollutants" for heavy metal nickel ions standard requirement

At the same time, due to the limited exchange capacity of the ion exchange resin, the exchange resin needs to be replaced frequently and the resin should be eluted and regenerated. Therefore, the actual operation cannot meet the requirements of the special discharge limit of water pollutants in Table 3.

[0010] The Chinese patent numbers are 200810205037.8 and 201110431946.X, both of which use ion exchange resins to treat heavy metal ions in electroplating wastewater and recycle them, but not for the purpose of treating wastewater up to standard discharge

The reason is that the exchange capacity of the ion exchange resin is limited, the exchange resin needs to be replaced frequently and the resin is eluted and regenerated, so the actual operation cannot meet the requirements of the discharge standard in Table 3 of the "Special Limits of Water Pollutants"

[0011] It can be seen that there are already many methods to meet the standard of electroplating wastewater treatment. The above methods are mainly aimed at the treatment process that meets the discharge standards in Table 2 of the "Special Limits of Water Pollutants". There is no economical and efficient way

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