Steel Industry Successful Case
The steel industry consumes a huge volume of water and discharges a large amount of waste water. Industrial waste water includes efflunet generated during the production and operation of various processes of steel enterprises, sewage and demineralized water from circulating cooling water systems, and concentrated brine produced when demineralized water and pure water are produced.
In recent years, with the promotion of energy-saving and emission reduction, the introduction of membrane water treatment process has been continuously advanced, the energy consumption of the iron and steel industry has been improved, and the fresh water consumption per ton of steel and the main pollutants discharge have been continuously reduced. In 2015, fresh waterconsumption per ton of steel dropped to a record low of 3.25m3;, with 36 companies whose fresh water consumption per ton of steel reached less than 3m3;. Compared with 2013, it decreased by 7.14%, and the water reuse rate reached 97.71%, an increase of 0.14% over 2013.
2. Case: Water recycling project of a large steel company
This company is a large-scale integrated steel enterprise and a stainless steel company with the largest production capacity and the most advanced technology and equipment in the world. In 2013, it produced 9.98 million tons of steel, realized sales income of RMB 146 billion , and profit of RMB500 million, taking a leading role in the industry.
In October 2008, it invested a new sewage treatment project, by which wasterwater would be treated and reused, functioning as a supplemented water source. Meanwhile, free service helped reduce the urban sewage discharge so that the industrial water recycling rate of this company reached over 98.2%。
Project Location：Shanxi China
Project Name：Industrial Waste water Recycle
Water Quality：Residential waste water + Steel production waste water
Use of Permeate Water：Process water
Time in Operation： Early in 2014
Type of Element： Fouling Resistant Elements
No. of Element： 1071 pcs
RO System Unit：（33:18）×7
Unit Volume： 200/h
No. of Vontron System：3 Units
3. Cost: Benefit Analysis
The designed water production capacity of this wastewater reuse project is 600 /h, with a daily output of 14,000 of qualified desalinated water. It can save 14,000 of fresh water every day, and about 52.5 million each year. Accounting for depreciation costs of fixed assets, energy consumption, chemical consumption, and labor management, the cost of qualified demineralized water production is about RMB 3.0 / ton, and the local industrial water price is RMB 3.40 / ton. If used as process water, further desalination is required. This project has continued to lead the industry in China in terms of water saving and emission reduction. and it has realized a "win-win" strategy for the treatment of water resources and the realization of wastewater functioning as resources.