With the tightening of environmental protection policies and the rising cost of water resources, the implementation of zero discharge transformation for desulfurization wastewater in thermal power plants has shifted from a "choice question" to a "mandatory question". However, how to select a reliable and economically feasible transformation route is a common challenge faced by many power plants. Baohupu Environmental Protection, based on years of technological research and project practice, has summarized a mature and efficient zero discharge process route for desulfurization wastewater, becoming a classic model in the industry.
I. Classic Process Route for Zero Discharge of Environmental-Safe Desulfurization Wastewater at Baohupu
The solution proposed by Baohupu is by no means a simple accumulation of technologies. Instead, it is a comprehensive and systematic design carried out based on the characteristics of desulfurization wastewater, such as "complex water quality, high salt content, and strong scaling property". Its core process route can be summarized as: "pre-treatment → membrane-based staged concentration → evaporation and crystallization for salt separation".
1. Preprocessing system (Fundamental role):
Objective: To remove Ca²⁺, Mg²⁺, SiO₂, suspended solids and some heavy metals from the wastewater, in order to prevent scaling and blockage of the subsequent membranes and evaporators.
Baihupu Solution: Utilizes a "chemical softening (lime + soda ash + flocculant) + tubular microfiltration (TMF)" combined process. TMF replaces the traditional sedimentation tank, with a smaller footprint and better water quality (SDI < 3), significantly enhancing the safety and stability of the subsequent membrane system.
2. Membrane concentration system (key to reduction):
Objective: To conduct high-scale concentration of the pre-treated fresh water, minimizing the amount of water entering the evaporation crystallization unit, thereby significantly reducing the investment and operating costs (evaporation crystallization energy consumption accounts for over 70% of the entire system).
Baihupu Solution: Utilizes a cascading concentration process of "reverse osmosis (RO) → high-pressure reverse osmosis (HPRO) → disc tube reverse osmosis (DTRO)". RO performs the initial desalination, HPRO takes on the main concentration task, and DTRO is responsible for the final ultimate concentration of the highly saline and high-hardness concentrated water. The overall system recovery rate can reach 95% - 97%. Baihupu Environmental Protection's experience in membrane selection, flow path design, and pollution control ensures the long-term stable operation of this system.
3. Evaporation Crystallization System (Ultimate Guarantee):
Objective: To completely solidify the extremely small amount of concentrated liquid produced by the membrane system, achieve a complete separation of salt and water, and realize the resource utilization of salt.
Baihupu Solution: The core component is a mechanical vapor recompression (MVR) evaporator combined with a crystallization salt separation system. The MVR technology has an extremely high thermal energy utilization rate and its operating cost is much lower than that of multi-effect evaporation. By precisely controlling parameters such as temperature and concentration during the crystallization process, sodium sulfate (Na₂SO₄) and sodium chloride (NaCl) in the wastewater are respectively crystallized to form industrial-grade products that can be sold externally. The impurity salt rate is controlled below 5%, truly achieving the dual goals of "zero discharge" and "resource utilization".
II. The technical advantages and innovation points of Baohupu Environmental Protection
Full-process optimization design: Focus on the coupling and coordination among various process units, rather than viewing them in isolation, to ensure the highest overall efficiency and the lowest cost of the system.
Core equipment and process packages: Possessing independently intellectual property rights, the efficient TMF pretreatment system, DTRO membrane system integration technology, and MVR desalination and crystallization process packages, with complete technical control capabilities.
Intelligent control system: Equipped with advanced DCS/SIS system, it enables real-time water quality monitoring, precise dosage of chemicals, fault early warning and intelligent regulation, ensuring the system operates under optimal conditions and reducing reliance on human resources.
Strong R&D and engineering capabilities: We have a pilot testing platform that enables us to conduct customized water quality tests for our clients, ensuring the scientificity and accuracy of the solutions; we also have an experienced project management team that guarantees the high-quality delivery of projects.
The zero-emission wastewater treatment solution for thermal power plants provided by Baohupu Environmental Protection is a proven, mature and economically reasonable classic route that has been verified in multiple large-scale projects. It not only helps power plants meet the strictest environmental protection regulations, but also generates long-term economic benefits through water resource reuse and salt resource utilization. It is an ideal choice for achieving a green transformation.
