Background
The waste water in hazardous waste disposal centers/landfill industries mainly includes acidic wastewater, process wastewater, cleaning wastewater, and high-temperature cooking wastewater. Considering various sources of wastewater, it is evident that wastewater originates from multiple hazardous processing processes, containing various alkaline substances and high concentrations of salts internally, which have poor biodegradability. Without treatment, it will irreversibly affect the water used in the production process equipment.
Due to the requirement for zero discharge of wastewater and the need for energy conservation and consumption reduction, the waste liquid finally sent to hazardous waste disposal centers/landfill centers mostly exhibits extremely high salt and COD contents, with a complex composition. The conventional incineration costs and subsequent exhaust gas treatment costs are increasing, leading to higher maintenance costs for equipment operation in hazardous waste disposal centers and ultimately reducing the profits of hazardous waste/landfill disposal companies.
Hazardous
Traditional hazardous waste disposal centers/landfill enterprises typically adopt the process of chemical coagulation/flocculation followed by membrane filtration before entering the biological treatment system. However, there are several challenges associated with this approach, including a lengthy overall process chain, large dosage of chemicals, poor process stability, additional sludge generation, and the need for maintenance and management by professional technical teams for the system.
WSD’s Solution
To address the challenge of concentrating and reducing electroplating wastewater, WSD has dedicated years of research and innovation to develop processes that maximize concentration and reduction: the Low Temperature Heat Pump Evaporation (LT-HP) process and the Low Temperature Evaporation Crystallization (LT-EC) process.
The LT-HP process incorporates a steam filtration system with an integrated steam purification filter (triple filtration in the vacuum tank), capable of removing over 99% of free organic compounds and free water. The effluent heavy metal content is reduced to zero, and the effluent COD is improved by 70% compared to traditional low-temperature evaporators before iteration. The effluent quality is superior and more transparent. The equipment is easy to operate, with a user-friendly interface designed to guide operators through parameter settings, troubleshooting, and maintenance reminders. Operators can easily follow step-by-step instructions to complete operations.
The Low Temperature Evaporation Crystallization (LT-EC) process employs Miller plate-type jacketed heat exchange for heat transfer. The vacuum level in the evaporation chamber is maintained at -95 to -97 kPa, and the evaporation temperature is typically kept between 40 to 45°C. Inside the evaporation chamber, a spiral blade stirrer is used to ensure uniform heating. Additionally, the stirrer is equipped with perimeter heating to enhance heat transfer efficiency and improve the dryness of the discharged material.
Advantages
1. It operates without generating harmful gas emissions or thermal pollution.
2. The system features fully automated control for seamless operation.
3. Its design is standardized, modular, and skid-mounted for easy installation and maintenance.
4. The evaporator includes automatic discharge and cleaning functions to enhance efficiency.
5. It is equipped with cloud platform management for remote monitoring and control.
6. The system supports companies in achieving zero discharge of hazardous wastewater.