Water is a fundamental natural resource and strategic economic resource that is closely related to the national economy and people's livelihood. Recently, the General Office of the Ministry of Industry and Information Technology released the "List of Typical Cases of Industrial Wastewater Recycling in 2024" (hereinafter referred to as the "List"), which selected a batch of typical cases of industrial wastewater recycling from five aspects: water use process recycling, regional industry city integration, smart water pipe control, technological equipment innovation, and collaborative pollution reduction and carbon reduction. These cases not only provide specific paths for improving water resource utilization efficiency, but also provide innovative demonstrations for promoting water-saving and intensification in the industrial field.

After years of effort, China has made overall positive progress in the recycling of industrial wastewater, with significant water-saving effects in the industry. Data shows that by 2023, the reuse rate of industrial water above designated size will reach 94%, achieving the goal proposed in the "Implementation Plan for Industrial Wastewater Recycling" jointly issued by the Ministry of Industry and Information Technology and six other ministries in 2021 ahead of schedule. The water consumption per 10000 yuan of industrial added value is 24.3 cubic meters, a decrease of about 20% compared to 2020, providing important support for achieving the national water consumption reduction target during the 14th Five Year Plan period.

"Over the years, the industrial sector has accelerated the transformation from water use to conservation and intensification, vigorously promoted water-saving technology and equipment, optimized the industrial water use structure, strengthened the management of water use in enterprises and parks, and made positive progress in promoting wastewater recycling." Zhao Xu, a researcher at the Ecological Environment Research Center of the Chinese Academy of Sciences, introduced that 58 enterprises and typical cases in parks selected in this "List" focused on steel, petrochemical, textile, papermaking, food and other industries have their own characteristics. Through innovative application of water-saving technology, transformation and upgrading, and digital empowerment, it has made multiple efforts, not only significantly improving water efficiency, but also significantly reducing the cost of water use for enterprises and minimizing the negative impact of sewage discharge on the environment. This is of great significance for promoting the technological transformation and upgrading of related industries and stimulating the green momentum of industrial development.

Promoting the recycling of industrial wastewater is not only a need to save water resources, but also a key measure to promote the green transformation of industries. Industry experts have stated that in recent years, especially in high water consuming industries such as steel, printing and dyeing, and papermaking, the recycling effect of industrial wastewater has been significant through a series of technological transformations and innovations.

In recent years, various industries have achieved significant results in water process recycling, smart water management, and technological equipment innovation. By strengthening the cycle of water use and innovating in water conservation, many enterprises actively promote the practice of circular economy.

Shougang Qian'an Iron and Steel has successfully solved the problem of circulating water concentration in high alkalinity and high hardness water sources by replacing traditional chemical agents with electrochemical descaling technology, achieving zero dosing of agents; In Hangzhou, Zhejiang Province, a printing and dyeing company has adopted internationally advanced membrane treatment systems and smart water management technologies, significantly improving the reuse rate of reclaimed water and water reuse; In Ningbo, Zhejiang, a pulp and paper company has achieved a water recycling rate of 93.2% by implementing measures such as graded water use, replacement of cooling water with white water, and fully enclosed circulation, significantly reducing water consumption and pollution discharge.

Supported by intelligent management and technological innovation, the resource utilization and emission reduction efficiency of industrial wastewater can be improved. Baosteel Zhanjiang Iron and Steel has established a water system centralized control center to achieve centralized control and intelligent collaboration of water resources, optimize refined management, and reduce water misallocation; In Changzhou, Jiangsu, a textile enterprise adopts ultrafiltration membrane+reverse osmosis technology and remote control system to achieve the resource utilization of high salt organic wastewater; In Rizhao, Shandong Province, a pulp and paper company has successfully achieved a combination of pre flocculation, anaerobic aerobic (A/O) biological treatment, post flocculation, sand filtration, and dual membrane treatment technology for lightly polluted wastewater generated during the production process. The company has achieved a water reuse rate of 95.93% and an annual recycled water usage of 6.6628 million cubic meters, combining source reduction and deep reuse of wastewater.

Chen Liyun from the China Iron and Steel Association believes that the "List" is of great significance for playing a leading role in water conservation and promoting the green transformation of the industry by selecting a group of typical cases with significant industrial wastewater recycling effects and advanced water efficiency indicators.

The next step is to promote the recycling of industrial wastewater through coordinated efforts in refinement, intensification, and digitization. Zhao Xu suggested that in the future, the structure of industrial water use should be optimized, non-traditional water sources should be expanded, water-saving technology innovation should be promoted, and wastewater should be reused for multiple purposes. At the same time, it is still necessary to improve the management mechanism of wastewater recycling, promote the construction of industry standards and policy support, further improve the efficiency of wastewater utilization, and polish the ecological background of new industrialization.