The steel industry, centered on the mining, beneficiation, smelting and processing of ferrous minerals, encompassing mining, ironmaking, steelmaking, steel rolling, ferroalloy smelting and metal product processing. It serves as a vital pillar of the national raw materials industry. The industrial chain extends into supporting sectors such as coking, refractory materials and carbon product manufacturing, and involves the mining and processing of strategic metal resources including chromium and manganese, forming a comprehensive industrial system.

Steel industry wastewater mainly includes six categories: cooling water, coking wastewater, desulfurization wastewater, pickling wastewater, cold-rolling wastewater and domestic sewage. Cooling wastewater has a large volume; coking wastewater contains refractory organic compounds and bio-toxic substances; desulfurization wastewater contains high salinity, high suspended solids and bio-toxic components; and pickling wastewater is highly acidic. Overall, treatment is highly challenging. Using its submerged ultrafiltration, pressurized ultrafiltration and reverse osmosis technologies, Shuiyi provides comprehensive wastewater treatment solutions for the industry, covering reclaimed water reuse, meeting discharge standards and (near) zero liquid discharge.