How to treat high salt wastewater?

The manufacturer of high-voltage electrostatic circulating water will explain to you how to treat high salt wastewater.

With the rapid development of China's economy, the increase of high salt wastewater discharge makes the treatment of high salt wastewater more difficult. How to choose the high salt wastewater treatment process? What are the advantages and disadvantages of high salt wastewater treatment process? How to treat these high salt wastewater?

High salinity wastewater refers to the wastewater containing organic matter and at least 3.5% (mass concentration) of total dissolved solids (TDS). This kind of wastewater comes from a wide range of sources. One is the chemical industry, pharmaceutical industry, petroleum industry, papermaking, dairy processing, food canning and other industrial production processes, which will discharge a large number of wastewater. The water not only contains a lot of high concentration of organic pollutants, but also a large number of calcium, sodium, chlorine, sulfate plasma. In order to make full use of water resources, some coastal cities directly use seawater as industrial production water or cooling water.

1. Traditional pretreatment process of medicated coagulation air flotation and sedimentation

When the COD concentration of the salty raw water is less than 5000mg / L, and there is no requirement for the quality of the crystal salt, the traditional process is that the salty raw water is pretreated by "regulation, dosing, coagulation, air flotation and sedimentation" before entering the "evaporation concentration crystallization desalination system". This method has the advantages of low investment and low operation cost, but the quality of crystal salt is poor and difficult to sell.

2. Fenton or electro Fenton Catalytic oxidation pretreatment process

Fenton reagent contains H2O2 and Fe2 +, which has strong oxidation ability to organic pollutants in wastewater, and has fast reaction speed and low investment. The effluent can be pretreated after precipitation and purification. But Fenton or electro Fenton Catalytic oxidation process requires specific reaction conditions: pH value 2-4, and produce more iron containing sludge, the effluent will have color. When the pH value of saline raw water is low, it is more economical to use, otherwise the process of "adding acid to reduce pH, adding alkali to neutralize" will increase the operation cost. The COD concentration is about 10000 mg / L. if it is too high, it needs multi-stage oxidation purification treatment, and Fenton process has no advantage.