High COD and high salinity wastewater evaporator

Selection Criteria

1. Evaporator Type:

• Forced Circulation Evaporator: Suitable for high-viscosity, high-salinity wastewater, effectively preventing scaling.

• Falling Film Evaporator: Suitable for heat-sensitive materials, enabling evaporation at lower temperatures.

2. Vacuum System: Lowers the boiling point through vacuum negative pressure, reducing the decomposition of heat-sensitive substances.

3. Automated Control: Equipped with a PLC control system for automatic monitoring and adjustment of parameters such as temperature, pressure, and liquid level.

4. Pretreatment: For wastewater with COD > 3000 mg/L, oxidation/coagulation pretreatment is required.

5. Online Cleaning System: Equipped with an online cleaning system to reduce maintenance time and costs.

Application Scenarios

1. Chemical Industry: 

• High-Salinity Wastewater Concentration and Reduction: Concentrates wastewater to a water content below 10%, producing clear evaporation water that meets discharge standards or can be reused.

• Case Study: A chemical company uses a low-temperature scraped-plate crystallization evaporator to treat 3600 tons of high-salinity, high-COD wastewater annually, saving millions of yuan in hazardous waste disposal costs.

2. Pharmaceutical Industry:

• Antibiotic Production Wastewater: Contains high concentrations of sodium sulfate, sodium chloride, and organic matter. MVR technology can achieve salt recovery and wastewater reduction.

• Synthetic Drug Wastewater: Contains high ammonia nitrogen and high COD. Resource utilization is achieved through a combined "electrodialysis + MVR" process.

3. Electroplating Industry:

• High-Salt, High-COD Wastewater Treatment: Low-temperature evaporators treat cutting fluids, emulsions, and other wastewater, achieving a COD removal rate ≥99%, with TDS of the treated water ≤50mg/L, meeting direct discharge or reuse standards.

4. Environmental Protection:

• Zero Wastewater Discharge: Low-temperature evaporation is used as an end-of-pipe treatment process, achieving 100% wastewater reuse.

Summary: Evaporators for high-COD, high-salt wastewater have significant advantages in treating such wastewater, effectively reducing wastewater volume, lowering energy consumption, and achieving resource recovery. When selecting an evaporator, the appropriate type, vacuum system, and automation control scheme should be chosen based on the specific properties and treatment requirements of the wastewater. By employing appropriate preprocessing and equipment selection, the stability and economy of the system can be further improved.