The desulfurization wastewater deep treatment project of the Phase III expansion project of Gudian Hanchuan Power Plant (hereinafter referred to as the Hanchuan Project) is EPC general contracted by Gudian Beijing Langxinming Environmental Protection Technology Co., Ltd. Nanjing Branch, and Hezhong Gaoko (Beijing) Environmental Protection Technology Co., Ltd. is responsible for the design, complete equipment supply, and technical services of the project's evaporation crystallization process section.

In view of the high energy consumption of the multi-effect evaporator operation, the general contractor, Gudian Langxinming Nanjing Branch, decided to adopt MVR evaporation crystallization technology. After technical performance demonstration and comprehensive selection by industry experts, Hezhong Gaoko won from several international bidding manufacturers and was responsible for the design and complete equipment supply. Based on the introduction of international well-known brand Weiting technology and product equipment, Hezhong Gaoko, through design and system integration optimization, designed the optimal MVR evaporation crystallization process scheme for this project.

After pretreatment softening, salt separation, and concentration reduction, the desulfurization wastewater of the Hanchuan project enters the MVR evaporation crystallization system. The solute in this part of the concentrated brine is mainly sodium chloride, with a concentrated brine volume of about 8t/h. The evaporated crystalline salt is dried by a fluidized bed and automatically packaged. The final product is bagged sodium chloride with a purity higher than 97.5%, reaching the secondary standard of refined industrial salt stipulated in GB/T5462-2003 Industrial Salt.

The project uses a DCS control system to perform online real-time monitoring of the process operation status, collect process parameters to automatically generate electronic spreadsheets, and operators can track and manage process operation data at any time, comprehensively improving the level of automatic control, improving the labor intensity and operating environment of operators. The implementation of this project can save the enterprise 280,000 tons of water and reduce the generation of about 7,000 tons of solid waste annually.

The desulfurization wastewater MVR evaporation crystallization technology provided by Hezhong Gaoko can be effectively combined with the salt separation process. While meeting the requirements of zero wastewater discharge, the solid waste is ultimately converted into refined secondary industrial salt. Compared with traditional technologies, the MVR evaporation crystallization system is more energy-efficient and environmentally friendly, saving about 60% or more of the operating costs compared to traditional multi-effect evaporators.

The successful implementation of the Gudian Hanchuan Power Plant desulfurization wastewater zero discharge project not only achieved true zero wastewater discharge but also achieved a circular economy, which has great significance for promotion.

Hezhong Gaoko has been deeply involved in the water treatment field for many years. As a supplier of membrane equipment and a provider of zero wastewater discharge solutions, its business covers more than 400 enterprises in 14 countries, with rich experience in handling different water qualities in different regions. The proprietary pilot plant built in 2016 can select different process technologies for industrial wastewater with different water qualities, combine them with MVR evaporation crystallization technology for experiments, and provide customers with more optimized and reliable design schemes through the accumulation of process parameters and data. The desulfurization wastewater MVR evaporation crystallization technology provided by Hezhong Gaoko can be effectively combined with the salt separation process. While meeting the requirements of zero wastewater discharge, the solid waste is ultimately converted into sodium chloride with a purity higher than 97.5%, reaching the secondary standard of refined industrial salt stipulated in GB/T5462-2003 Industrial Salt. The implementation of this project (calculated based on 5000h of annual power generation) reduces the annual discharge of wastewater by 180,000 m³, reduces the annual discharge of solid waste by 5040t, and produces 4000t of secondary industrial salt annually.

The successful implementation of the Gudian Hanchuan Power Plant desulfurization wastewater zero discharge project not only achieved true zero wastewater discharge but also achieved comprehensive utilization and reduction of solid waste, which has great significance for promotion.

In the future, Hezhong Gaoko will continue to provide owners with the most suitable zero-discharge solutions for on-site water quality conditions with perfect process design. Adhering to the principle of "affordable, usable, mainstream technology, mature technology", we help owners reduce water treatment costs, improve economic benefits, and bring more advanced technologies and more professional services to the industrial wastewater treatment field.