SMM: in order to implement the National Water Saving Action Plan and continuously improve the efficiency of industrial water use, the Ministry of Industry and Information Technology, together with the Ministry of Water Resources, the Development and Reform Commission, and the General Administration of Market Supervision, launched a leading action for water efficiency leaders in 2020. Recently, 30 water efficiency leaders have been selected from 10 industries, including iron and steel, petroleum refining, modern coal chemical industry, ethylene, chlor-alkali, nitrogenous fertilizer, papermaking, textile dyeing and finishing, chemical fiber filament weaving, beer and so on. In order to give full play to the leading demonstration and typical leading role of water efficiency leaders, promote water-saving experience and technology, and promote enterprises to meet water efficiency standards, we have combed the advanced experience of some leading enterprises in different industries for reference.
The iron and steel industry is one of the pillar industries of our national economy. China's steel output exceeds half of the world's total steel output, ranking first in the world. From 2010 to 2019, China's steel output grew at an average annual rate of about 5.1%, but the overall water consumption of the iron and steel industry showed a downward trend. The water intake per ton of steel in key enterprises dropped from 4.1m3 to 2.7m3, realizing "increasing steel without increasing water".
The water efficiency leaders of key water users in the iron and steel industry in 2020 include Delong Iron and Steel Co., Ltd., Tianjin Rongcheng United Iron and Steel Group Co., Ltd., Baosteel Zhanjiang Iron and Steel Co., Ltd., Shougang Co., Ltd. Qian'an Iron and Steel Co., Ltd. Water efficiency leaders will strengthen water-saving management, implement the transformation of water-saving technology and equipment, reduce water consumption and improve water use efficiency. The main practices include:
First, strengthen water-saving management and system construction. Formulate a sound water intake management system and assessment methods, set up a leading group for water-saving management, clarify responsibilities, implement award-saving and over-punishment, and strengthen water-saving target management. For example, Delong Iron and Steel Co., Ltd. carries out the "five small innovations" activities of "small innovation, gadget, small transformation, small design, and small suggestions" to enhance the enthusiasm of employees to participate in water saving.
The second is to implement information and visual management of water use. Establish water system data center and integrated management and control platform, strengthen process water consumption index and fine management of water balance in the whole plant, find problems in time and rectify them. For example, Baosteel Zhanjiang Iron and Steel Co., Ltd. has established a digital water control center and information management system to carry out water system management and daily production management of the whole plant, so as to achieve "one table of water quantity of the whole plant and one map of production monitoring", so as to improve the level of water management in an all-round way.
The third is to strengthen the development and utilization of unconventional water resources. Tianjin Rongcheng United Iron and Steel Group Co., Ltd. continues to optimize the structure of water resources and increase the proportion of purchased municipal reclaimed water, municipal sewage and self-storage Rain Water. Baosteel Zhanjiang Iron and Steel Co., Ltd. made full use of geographical advantages, through Rain Water collection and utilization and low-temperature multi-effect distillation seawater desalination technology, greatly reduced the use of surface fresh water, 2019 tons of steel products to draw 1.66m3 of water.
Fourth, the application of advanced water-saving technology. The "three dry" processes such as coke oven dry quenching, blast furnace dry dedusting and converter dry dedusting are adopted. as well as cascade water use, closed circulation of cooling water, condensate recovery, comprehensive discharge sewage recycling, concentrated brine reverse osmosis reduction, coking and other high pollution wastewater treatment and reuse, to achieve water saving and pollution reduction. For example, the Qianan Iron and Steel Company of Shougang Co., Ltd. has built the largest comprehensive circulating water pumping station in Asia, and equipped with a complete water supply and drainage network system of different quality, so as to realize the resource utilization of sewage and efficient water saving.
