Zero Wastewater Discharge in the Steel Industry Requires Finding Methods

Zero wastewater discharge generally refers to the phenomenon where industrial wastewater is treated, recycled, and reused, ultimately resulting in no waste liquid discharge. This leads to higher resource utilization and reduced environmental pollution. In some industrial sectors, high water consumption is a given, making the promotion of zero wastewater discharge a crucial environmental protection direction.

Several national policies have also clearly stated the need to accelerate the comprehensive utilization of industrial resources and promote the recycling of industrial wastewater. Policies specify that the reuse rate of industrial water in large-scale industries such as steel, petrochemicals, and non-ferrous metals must reach over 94%. By 2025, a new pattern of efficient wastewater recycling in major water-consuming industries will be basically formed.

The steel industry’s operation relies heavily on water consumption, resulting in substantial wastewater discharge. The integration of zero wastewater discharge with the steel industry is an inevitable trend in green development. It should be recognized that zero wastewater discharge and the steel industry are currently in a “trial period,” requiring a gradual approach. This is a case of not being able to rush things.

Experts with years of experience in the resource utilization of wastewater in the steel industry point out that the current focus of the steel industry should be on the treatment of concentrated brine at the end of the entire plant’s water circulation system, rather than excessively pursuing “zero wastewater discharge.” The approach should be determined based on capacity and circumstances.

Only by bridging the gap between ideal and reality can zero wastewater discharge truly achieve a perfect combination of pollution reduction and higher resource utilization. Difficulties exist, and it will require the test of time. Currently, while deep treatment of wastewater may transform it into reusable resource products, it may also produce some unabsorbable concentrated brine, or present a series of practical problems such as high operating costs and difficult system maintenance.

The “Implementation Plan for the Resource Utilization of Industrial Wastewater” issued by the relevant department proposes that by 2025, the industrial water reuse rate in the steel industry should exceed 97%. Indeed, the policy places high demands on the water resource utilization efficiency of the steel industry. However, it should also be recognized that there are many feasible solutions for the green transformation of the steel industry that can be integrated into the zero wastewater discharge track.

Industry insiders believe that the steel industry should gradually develop from internal water circulation to regional water circulation systems. To achieve water recycling across different entities such as enterprises and communities, a closed-loop system for water resource utilization will be established, enabling wider-scale water resource recycling and assisting the steel industry in improving water resource utilization efficiency, thus forming a new pattern of industrial water resource recycling.

Steel industry wastewater has a complex composition and can cause various environmental pollution problems. Therefore, it is currently necessary to prioritize solving the prominent problems in industrial wastewater and gradually move towards zero wastewater discharge.

However, it is certain that with the advancement of zero wastewater discharge technology, the discharge of water pollutants will continuously approach “zero,” and there is still a long way to go to achieve zero wastewater discharge.