Headed by extraction of six industrial nickel electroplating wastewater treatment methods
nickel is a hard and corrosion resistant germplasm of heavy metals, often used in electroplating industry. Generate a lot of nickel electroplating industrial wastewater, can cause serious pollution to the environment. In nickel plating rinse water, contain large amounts of nickel sulfate and nickel chloride, nickel compounds can stimulate the body's pure ammonia enzyme, carboxylase, cause all sorts of inflammation, damage cardiac muscle and liver. At the same time, the nickel is a kind of carcinogenic substance. So to explore an effective and economic nickel wastewater treatment method is of great significance to environmental protection.
mainly comes from the metal plating wastewater containing nickel plating parts in the process of pretreatment of pickling, rinsing and some acid plating bath, such as acid copper plating, nickel plating rinse water after plating. At present, for nickel electroplating wastewater treatment methods mainly include chemical method and ion exchange method, evaporation concentration and membrane separation technology and biological method and solvent extraction nickel wastewater treatment.
chemical nickel electroplating waste water chemical treatment effect is stable and reliable, mature technology, chemical method, however, more widespread drug consumption and the high cost of processing, shortcomings and so on to produce a large number of nickel slag, easy to cause secondary pollution, improper handling can not effective recovery of nickel and water resources. Along with the development of the new type of precipitator, the use of waste residue, and combined with other technology development, the law will also get further development.
ion exchange method and treatment of nickel electroplating wastewater
the nickel salt price is higher, in order to save resources, nickel wastewater treatment by ion exchange method. Because of its suitable for processing low concentration and large quantity of waste nickel plating wastewater, has been widely used. The main features are: ( 1) Removal of heavy metals Ni2 +; ( 2) Valuable metal nickel in waste water recycling; ( 3) Improve the utilization rate of the water cycle; ( 4) Reduce the pollution of the environment. In recent years, with interest in nickel plating wastewater resource is more and more strong, ion exchange technique used as an effective method to electroplating wastewater deep treatment has caused people's attention.
evaporation concentration nickel electroplating wastewater treatment is
evaporative enrichment process of electroplating waste water in the condition of atmospheric pressure or vacuum heating, make the solvent evaporation and concentration of wastewater to method. Concentrated solution can return plating tank, after evaporation of the water vapor by condensation recovery after can be used to supplement to clean water or recycling tank water. When to use it at the time, can realize the waste water 'zero emissions'. Can be used with ion exchange method.
membrane separation technology nickel electroplating wastewater treatment
as a high-tech membrane separation technology, because of its separation, high efficiency, energy saving, no secondary pollution, the advantages of convenient operation, covers an area of less, gradually is widely used in electroplating wastewater treatment.
biological treatment containing nickel electroplating wastewater biological treatment of electroplating wastewater is heavily dependent on cultured bacteria to complete the complex function. The functional bacteria have electrostatic adsorption, enzyme catalytic conversion function, complexation, flocculation, parcel coprecipitation role and effect on pH buffer. Waste water of heavy metal ions such as Ni adsorption and complexation is formed by bacteria, after the solid-liquid separation, wastewater discharge or reuse, while the heavy metal ion precipitation sludge.
solvent extraction nickel electroplating wastewater treatment
refers to a liquid liquid three-phase system with three liquid phase extraction separation system, the two layers of a layer of water phase and organic phase and organic phase and the first known as organic phase, on the upper deck of the system ( Rich in organic solvent) , the second organic phase is also called the third phase or organic phase, exist in the system of the middle layer ( Rich in being an metal ions) The water in the bottom of the three-phase system. Using a liquid liquid phase extraction process, at the same time to obtain a variety of different polarity products, greatly improving the separation efficiency.
with the in-depth study of the three-phase system, they try to apply the special properties of the third phase in the separation process, especially to contain a variety of heavy metal wastewater realize one-time extraction and recovery on the processing of a variety of metal ions.