Fur dyeing wastewater has the characteristics of high chroma, high Cr3 + content, acidity, and complex components, so it is difficult to treat.
In domestic and foreign researches on fur dyeing wastewater treatment methods, dyeing wastewater is mostly used as a kind of sewage, and the purpose of research is to make dyeing wastewater meet the sewage discharge requirements after treatment.
The decolorization methods of dyeing wastewater reported in the research include adsorption method, oxidation method, coagulation method, electrochemical method, membrane separation method, and biological method.
Electrochemical method is a treatment method that directly or indirectly uses electrochemical reactions to convert colored groups in waste water to colorless groups to remove the chromaticity of dyeing wastewater.
According to the different electrode reaction methods, it can be divided into internal electrolysis method, electrocoagulation method, and electrocatalytic oxidation method.
The advantages of the internal electrolysis method are that it can treat waste with waste, does not consume energy, can remove a variety of pollution components and chromaticity, and can also improve the biodegradability of refractory materials.
The disadvantages are slow reaction speed, easy reaction column clogging, difficult treatment of high-concentration wastewater, and poor reactor operation flexibility.
Electrocoagulation has the advantages of simple equipment and convenient operation.
It has a good treatment effect on water-insoluble dyes and dye intermediates containing a NOZ.
The disadvantage is that it has a poor treatment effect on acidic and reactive dyes that have better water solubility.
The method consumes a large amount of power, and the anode metal is easy to be consumed, which may cause secondary pollution such as sludge.
The advantages of the membrane separation method are high separation efficiency, low energy consumption, simple recyclable process, convenient operation, and no secondary pollution. Lower dye and dye intermediate wastewater, so it has not yet been promoted.
Biological method is a treatment method that uses the metabolism of microorganisms to oxidize and decompose organic substances in wastewater. According to the different aerobic requirements of microorganisms, biological methods can be divided into two categories: aerobic treatment methods and anaerobic treatment methods.
A commonly used biological treatment method mainly includes activated sludge method and biofilm method. Both the activated sludge method and biofilm method have the same problem, that is, the removal rate of COD and chromaticity is not high, and the system treated effluent cannot reach the required level.
Emission standards, and more importantly, the disposal of excess sludge and high operating costs make it unbearable for companies.