Method for removing nickel in chemical nickel-plating wastewater

Abstract

The invention discloses a method for removing nickel in chemical nickel-plating wastewater, comprising the steps of: (1) chelation reaction: reacting nickel in wastewater with a chelant to form a nickel chelate; (2) composite flocculation precipitation: subjecting a polymeric Mg-Fe composite flocculant and the nickel chelate obtained in the step (1) to composite flocculation precipitation; and (3) multimedium filtration: filtering the wastewater subjected to the composite flocculation precipitation in the step (2) by adopting a multimedium filter method. The treated wastewater is discharged when nickel content in outflow water reaches the standard. The method has the advantages of good treatment effect, simplicity for operation and management and low operation cost and is a good method for removing the nickel in the chemical nickel-plating wastewater.

Description

technical field [0001] The invention relates to a wastewater treatment method, in particular to a method for removing nickel in nickel-containing wastewater. Background technique [0002] At present, chemical nickel wastewater, that is, the wastewater produced in electroless nickel plating, often contains complex nickel, and it is difficult to make it up to standard by conventional methods. The pollution problem has always been an urgent problem to be solved in heavy metal wastewater treatment projects. The total nickel in this kind of nickel-chemical wastewater is 20-50mg / L, because part of the nickel contained exists in a complex state, the traditional method can only treat 0.6-1.3mg / L, and cannot effectively treat the electroplating wastewater pollutants The discharge standard (GB21900-2008) in Table 3 requires the total nickel to be less than 0.1mg / L, which puts a lot of pressure on the company's environmental protection. In order to solve the problem of environmental p...

AI Technical Summary

Problems solved by technology

[0002] At present, nickel chemical wastewater, that is, wastewater produced in electroless nickel plating, often contains complex nickel, and conventional methods are difficult to make it up to standard. The pollution problem has always been an urgent problem to be overcome in heavy metal wastewater treatment projects.

The total nickel in this kind of nickel-chemical wastewater is 20-50mg / L, because part of the nickel contained exists in a complex state, the traditional method can only treat 0.6-1.3mg / L, and cannot effectively treat the electroplating wastewater pollutants The emission standard (GB21900-2008) in Table 3 requires the total nickel to be below 0.1mg / L, which puts a lot of pressure on the company's environmental protection

In order to solve the problem of environmental pollution caused by heavy metal wastewater in the electroplating industry, it is urgent to develop an efficient, low-cost, and easy-to-operate process technology suitable for this type of wastewater treatment

[0003] At present, the commonly used methods for the treatment of nickel wastewater are chemical precipitation, membrane separation technology, and ion exchange. These methods all have problems such as unqualified discharge, high cost, long-term operation, and cumbersome operation and management.

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