Recently, BGT has received the notice of winning the bid for the procurement project of high-salinity water reduction disposal service for the evaporation pond in Ordos Energy & Chemical Tuke Factory Area!

China Coal Ordos Energy & Chemical Co., Ltd., established in June 2011, is the first coal chemical enterprise independently built by China Coal Energy Co., Ltd. in the Inner Mongolia-Shaanxi region. It is mainly responsible for the professional management of coal chemical industry in the Ordos region under China Coal Group.

This project adopts the BOO (Build-Own-Operate) model. BGT will provide equipment and technologies, and be responsible for operation and maintenance, to treat 50,000 cubic meters of high-salinity water in the evaporation pond of Ordos Energy & Chemical Tuke Factory Area.

BGT's independently developed zero-discharge salt separation technology for high-salinity wastewater mainly treats the strong brine formed after reduction. It aims to control salt content for water discharge, realize the resource utilization of inorganic salts by separating high-quality chemical raw materials, and enable the recycled use of the remaining treated water. It is a key technology to achieve zero discharge of industrial wastewater.

At present, companies in the industry generally use evaporation crystallization to treat strong brine. The evaporation crystallization process is based on the principle that inorganic salts have different solubilities under different temperature conditions to achieve crystallization and precipitation. The distillate is collected into a distilled water tank, then transported to heat exchange equipment for heat exchange with incoming liquid. After cooling down, it leaves the evaporation crystallization system and is sent to the reuse water pool for reuse. However, this method has major defects. Evaporation crystallization equipment is prone to coking, scaling, blockage, corrosion, and system foaming, which leads to a rapid decline in the evaporation and crystallization capacity of the equipment, and causes the produced salt to have high chromaticity and odor, making the salt separation products unable to be recycled. In addition, due to large fluctuations in the quality of incoming water, the quality of separated salt cannot be guaranteed, and the output of the salt separation system is often mixed salt. Due to these comprehensive reasons, the final content of miscellaneous salt exceeds the design value, and the miscellaneous salt is highly hazardous waste with high treatment costs. Considering that large industrial enterprises, such as coal chemical enterprises, usually have an annual total salt output of 30,000 to 70,000 tons, and up to more than 100,000 tons, the salt separation and zero-discharge technology must achieve the operation goals of long-term stability and high-quality salt production; otherwise, it will generate high treatment costs and cause serious resource waste.

Given the complexity of zero-discharge salt separation, BGT has organized professional R&D personnel and engineering technicians from various fields to investigate and analyze the experience and lessons of projects put into operation at home and abroad from the perspectives of environmental engineering, chemical unit operations, chemical equipment and automation, analytical chemistry, and material chemistry. It has researched and developed the entire process of zero-discharge salt separation, forming the Company's own high-salinity wastewater salt separation and zero-discharge process technology. The core of this salt separation process consists of "deep concentration process + fractional salt crystallization process". It uses electric-driven membrane and MVR concentration units for deep concentration, followed by freezing/nanofiltration coupled salt separation and evaporation crystallization.

This process has loose requirements on the quality of incoming water, featuring low treatment cost and low miscellaneous salt rate in the produced salt. A typical project is the China Coal Yuanxing Phase II Project. Invested and constructed by China Coal Yuanxing and undertaken by BGT as the EPC general contractor for zero-discharge salt separation and crystallization, it is a large-scale zero-discharge salt separation and crystallization project. The output of salt separation products reaches 110,000 tons per year, with a miscellaneous salt rate of less than 5%. The salt quality can meet the standards of Class I Grade A for sodium sulfate in industrial sewage (GB/T600P-2014) and Grade I for sodium chloride according to Industrial Salt (GB/T5462-2015). In 2020, it was evaluated at the expert appraisal meeting organized by the China Chemical Environmental Protection Association as "generally reaching the international advanced level, with some units reaching the international leading level".