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Recycling of Wastewater Discharged by Shaanxi Shanjiao Company Author/Source: China Chemical Industry News Date: April 15, 2019 Clicks: 7 At the beginning of April, the wastewater treatment project for the desalination water station of Shaanxi Shanjiao Chemical Co., Ltd. entered the commissioning phase after more than 6 months of construction. This is a project aimed at recycling the wastewater discharged from the desalinated water treatment plant operated by this company, which currently has 3 boilers with a capacity of 75 tons per hour. The project enables the treatment of 525,600 tons of wastewater per year, resulting in a reduction of 394,200 cubic meters of wastewater discharged; the wastewater recycling rate exceeds 75%, allowing all the discharged wastewater to be fully recycled using the existing processing methods. The desalination station is an auxiliary device attached to the boiler, designed to provide high-standard desalinated water for gasification; the purification process generates large amounts of wastewater, including RO concentrated brine and backwash water. To conserve precious water resources, after thorough investigation and evaluation, the company decided to recycle RO concentrated brine, backwash water, and reclaimed water. Last October, the company began construction of a wastewater treatment plant for discharging treated water, with a design capacity of 60 cubic meters per hour, in order to generate supplementary water sources that meet the requirements of the recirculation water system. It is understood that among the wastewater discharged from the desalinated water station, the largest volume is that of RO concentrated brine, which mainly contains soluble inorganic salts as well as calcium and magnesium that cause hardness. This project involves adding special chemicals to cause anions to form complex compound precipitates, which are then removed permanently from the water body. Other dissolved total solids are removed through a two-stage filtration process involving precision filtration and reverse osmosis. The backwash water mainly contains particles and microorganisms; the high-performance composite flocculant JT-02 is used for flocculation and precipitation, as well as multi-media filtration, in order to remove impurities and effectively reduce pollutant emissions.