[Ocean Chemical News] There is a new plan for the treatment of high salt water content in coal chemical projects

Industrial salt coal chemical industry is a resource-intensive industry that consumes large amounts of water resources and pollutants. The composition of high-salt wastewater from the coal chemical industry is complex. In addition to large amounts of chloride, sulfate, and nitrate, it also contains various organic pollutants such as phenol, cyanide, condensed aromatic hydrocarbons, quinoline, pyridine, indole, and biphenyl, making it difficult to treat. At present, most coal chemical companies use evaporation and crystallization processes to purify high-salt wastewater. However, energy consumption is large and the cost of reusing a ton of water is high. The treatment cost per ton of wastewater is 30 to 40 yuan. The economic benefits of water recycling alone cannot offset the cost of treatment. Not only is the cost of wastewater treatment high, but evaporation and crystallization will also produce more than 50 kilograms of mixed salt residue per ton of water. The composition is complex, easy to dissolve and difficult to solidify. It is prone to leaching, infiltration and other phenomena after landfill, making it a potential source of secondary pollution. The cost of processing mixed salt is as high as 3,000 yuan/ton, which increases the operating burden of the company. Sinopec’s new technology solves this problem. In Yinchuan, Ningxia, at the site of the coal gasification key technology project for resource utilization of high salt content crystallization, the high salt content wastewater in the white water tank undergoes a combination of pretreatment and purification, membrane concentration, organic matter degradation and removal, and fractional crystallization to finally obtain Baihuahua industrial salt. At the same time, the new technology can reduce energy consumption by about 45% to 50% by combining the coupling membrane concentration system and the MVR evaporation system, and processing 1 ton of high salt water only produces 3.4 kilograms of mixed salt residue, and the residue treatment fee * * reduce.

Four types of industrial salts with high added value. The four types of industrial salt produced by this technology to treat high salt water content are calcium sulfate whiskers, sodium sulfate, sodium chloride, and sodium nitrate. They are high value-added products. In the "Pilot Test Report on Key Technologies for Resource Utilization of High Salt Water Content in Coal Gasification", Chen Xin, deputy director of the Environmental Protection Office of Ningbo Engineering Company, gave a detailed introduction to this. Calcium sulfate whiskers with high added value have many excellent properties such as high strength, high modulus, high toughness, high insulation, wear resistance, high temperature resistance, acid and alkali resistance, corrosion resistance, non-toxicity, etc., and can be used as reinforcing and toughening agents or functional fillers in resins, plastics, papermaking and other materials. ； It can be directly used as filter materials, thermal insulation materials, refractory insulation materials, infrared reflective materials and high insulation materials for covering wires. It has broad market application space and high value return. At the same time, three industrial products such as sodium sulfate, sodium chloride, and sodium nitrate produced by crystallization also have market value.

“The new technology realizes the fractional crystallization and resource utilization of wastewater inorganic salts. All four industrial salt products meet the quality requirements * * Standard requirements, obvious quality competitiveness and broad market application space, it is a veritable treasure. ”Guo Wenyuan, executive vice president of Ningbo Technology Research Institute, is full of confidence in the disruptive changes that new technologies will bring to high-salt wastewater in the coal chemical industry. According to estimates, the sales revenue of industrial salt products obtained from processing 1 ton of high-salt wastewater can range from 12.32 yuan to 75.08 yuan. “The new technology of fractional crystallization is used for treatment, which reduces the pressure of enterprise wastewater discharge, reduces the discharge of waste liquid and residue, realizes green treatment and resource utilization of high-salt wastewater, and significantly improves environmental protection benefits. ”Professor Jin Yan from East China University of Science and Technology is very satisfied with the pilot test results of the new technology

The technology is novel in the world. The key technology for resource utilization of high-salt water crystallization in coal gasification is novel in the world. Among them, "an improved crystallizer suitable for high-salt wastewater mass crystallization" has been applied for.* * Invention patents, 8 patents are being applied for. Wang Zizong, deputy chief engineer of the group company, affirmed the necessity and innovation of new technologies. He said that the new technology is in line with the group company's guiding ideology of "source control, process management, and terminal treatment" of high-salt wastewater, reduces the cost of high-salt water treatment, and is in line with the trend of green development. In particular, the project's salt recovery rate reaches 96%, which is the highest in the country and is highly innovative.

The intellectual property rights of this project are disputed. The high salt water "zero discharge" project of Sinopec Great Wall Energy and Chemical (Ningxia) Company consists of a reduction device and an evaporation and crystallization device. Sinopec Ningbo Engineering Company, as the leader of the EPC consortium, jointly EPC general contracted the reduction device with Beijing Beijite Environmental Technology Company (member party), and jointly EPC general contracted the evaporation and crystallization device with Jiangsu Zhongsheng High-tech Engineering Company (member party). The project was put into operation in 2016 and reached the design capacity. If we talk about the "key technologies for resource utilization of coal gasification high-salt content crystallization" developed through this project, it should at least include Beijite and Zhongsheng, because the two companies have provided process packages and EPC respectively.

Thank you, it turned out to be from Ningbo Engineering Company. Now that I am in Argentina, it is really comfortable to communicate with the master. Thank you, God

Many people from engineering companies in the east have stepped out and broadened their horizons.