[Chinese Mainland] BGT Wins China's Largest Desulfurization Wastewater Zero Liquid Discharge Salt Separation Project: 330 m³/h, Producing Chlor-Alkali-Grade Industrial Salt for Closed-Loop Reuse

An enterprise in Beijing E-Town, Beijiete, recently won the bid for the Phase I Project of the Desulfurization Wastewater Zero Liquid Discharge Treatment System of Liaocheng Xinyuan Group Co., Ltd. (Xinfa Group), with a treatment capacity of 330 m³/h, making it currently the largest desulfurization wastewater zero liquid discharge salt separation project in China. The project adopts a complete process package of "high-efficiency sedimentation + filtration — ultrafiltration + reverse osmosis + electro-driven membrane multi-stage concentration — freezing/nanofiltration coupled salt separation + MVR evaporative crystallization", producing industrial salts of sodium chloride and sodium sulfate, among which the sodium chloride quality meets the raw material requirements of the chlor-alkali industry and can be fully reused in Xinfa Group's chlor-alkali production line.

I. The "Toughest Nut to Crack" in Coal-Fired Power Plants

Wastewater generated by wet desulfurization of large coal-fired units is widely recognized as a highly difficult subject in the field of industrial wastewater treatment: high salinity, large water quality fluctuations, and complex composition, containing high concentrations of sodium chloride, sodium sulfate, as well as calcium, magnesium, heavy metals and other pollutants. The treatment difficulty lies not only in the deep separation of salts, but also in the continuous challenge posed by fluctuating influent water quality to system stability.

Recently, Beijiete, an enterprise in Beijing Economic-Technological Development Area, announced that the company successfully won the bid for the Phase I Project of the Desulfurization Wastewater Zero Liquid Discharge Treatment System of Liaocheng Xinyuan Group Co., Ltd. (Xinfa Group), with a desulfurization wastewater treatment capacity of 330 m³/h. According to the official release of Beijing E-Town, this project is currently the largest desulfurization wastewater zero liquid discharge salt separation project in China, marking that Beijiete's technical and engineering capabilities in the field of desulfurization wastewater resource recovery have once again gained industry recognition.

II. Four-Step Breakdown of the Process Route

Beijiete adopted its self-developed complete process for zero liquid discharge and salt separation of high-salinity wastewater for this project. The route can be broken down into four steps:

• Pretreatment — Adopting the "high-efficiency sedimentation + filtration combination" process to remove suspended solids, calcium and magnesium hardness, and heavy metal ions from the wastewater, safeguarding the stable operation of the subsequent membrane system.
• Multi-stage Concentration — Adopting the "ultrafiltration + reverse osmosis + electro-driven membrane" multi-stage concentration process to reduce the wastewater to its minimum volume, significantly lowering the investment and operating costs of the subsequent evaporative crystallization stage.
• Salt Separation and Purification — Through freezing/nanofiltration coupled salt separation technology and MVR evaporative crystallization process, achieving efficient separation of sodium chloride and sodium sulfate, and producing high-quality salt products that meet industrial salt standards.
• Closed-Loop Reuse — The sodium chloride produced by the project meets the raw material requirements of the chlor-alkali industry and can be fully reused in Xinfa Group's chlor-alkali production line.

According to the contract arrangement, Beijiete will undertake all work for the desulfurization wastewater zero liquid discharge system, including process design, equipment supply, installation guidance, modification of existing equipment, overall commissioning, trial operation, and personnel training, and will also design supporting systems such as civil engineering, fire protection, and HVAC, making it a typical "turnkey" general contracting service.

III. The Business Logic of "Turning Wastewater into Resources and Mixed Salts into Products"

The pain point of desulfurization wastewater zero liquid discharge has never been merely "treating the water clean." The mixed salts produced by the traditional evaporative crystallization pathway fall within the category of hazardous waste, and their disposal costs are high, constituting a long-term cost burden on power plants. The value of salt separation technology lies precisely here: purifying sodium chloride and sodium sulfate separately to industrial product standards, turning mixed salts from a "burden requiring paid disposal" into "products that can be sold or used internally."

The closed-loop design of this project is particularly noteworthy: Xinfa Group is a large enterprise group integrating power generation, aluminum, and chlor-alkali chemicals. The chlor-alkali-grade sodium chloride extracted from the power plant's desulfurization wastewater is directly supplied back to the group's own chlor-alkali production line, forming an intra-industrial circulation of "power plant desulfurization — wastewater treatment — salt resource recovery — chlor-alkali production." The output of wastewater treatment is consumed without leaving the group, which is the most ideal economic model for zero liquid discharge projects — compared with salt product sales relying on external markets, an internal closed loop is more immune to price fluctuations.

IV. Dual Drivers from Policy and Market

The "zero liquid discharge + resource recovery" of high-salinity wastewater is becoming a clear policy and market direction. On the one hand, regulatory supervision over the discharge of high-salinity wastewater from industrial parks in the Yellow River Basin and key regions continues to tighten; on the other hand, the demand for stock renovation in the treatment of "three wastes" in the coal power industry is enormous, and desulfurization wastewater zero liquid discharge is one of the core scenarios. 10月12日, Jiangxi Ganneng Fengcheng Power Plant also issued a tender for zero liquid discharge renovation of the entire plant's wastewater (circulating water blowdown treatment scale of 200 m³/h, system recovery rate of no less than 75%, control price of 1175万 yuan), indicating that zero liquid discharge renovation of wastewater on the power generation side has entered a stage of large-scale implementation.

Unlike municipal wastewater resource recovery, the value realization path of industrial high-salinity wastewater relies more on the integration capability of unit technologies such as salt separation, crystallization, and resource reuse, as well as coupled design with the owner's industrial chain. Whoever can balance the overall economic account of "water — salt — reuse" will be able to take the initiative in this round of renovation cycles.

V. Observing Trends from a Single Case

Broadening the perspective, this project and the recent surge of industrial wastewater salt resource recovery cases form part of the same trend: the Urumqi Ganquanbao Industrial Park wastewater resource recovery project achieves a water recovery rate of 98% and produces industrial salt through membrane concentration and evaporative crystallization, while industrial reuse projects in Spain and France are also shifting toward "resource recovery." It can be judged that "zero liquid discharge" is evolving from an environmental compliance goal into a resource management strategy—when both the water and salt in wastewater can enter the production cycle, zero liquid discharge turns from a cost item into an asset item. For equipment and engineering enterprises, the degree of independent development of core technologies such as multi-stage membrane concentration, salt separation crystallization, and MVR energy saving will directly determine their market position in the next industrial upgrading cycle.

TIANYI TECH Co., Ltd. (TIANYI LIMITED) has long been deeply engaged in the fields of wastewater treatment and reclaimed water reuse. Centering on three major directions—low-carbon processes, resource recovery, and smart operations—it provides full-chain services from solution design, equipment manufacturing, engineering construction to operation management for municipal wastewater treatment plants, industrial parks, and various water-using entities. With the goal of "stable compliance, energy saving and consumption reduction, and resource circulation," the company continuously helps customers reduce operating costs and enhance system resilience in the green and low-carbon transition.

Source: Beijing Economic-Technological Development Area official website "Beijiete Wins Bid for the Largest Desulfurization Wastewater Zero Liquid Discharge Salt Separation Project in China" (2026年10月14日) and publicly available information.