Organization of Water Protection Activities at PAO Severstal

Evolution of Industrial Water Supply: From Discharges to Closed Cycles

Water resource management at large metallurgical enterprises has long gone beyond simple compliance with regulations. Today, it is a complex engineering and environmental task that requires a balance between production needs and ecosystem preservation. During the webinar, Renata Efremova, Water Protection Manager at PAO Severstal, discusses the practical experience of transforming the water supply system of the plant located on the shores of the Rybinsk Reservoir.

Why a 100% Closed-Loop Cycle is an Ecological Trap

In the professional community, the thesis about the need to transition to a fully closed-loop water consumption cycle is often heard. However, the speaker clearly demonstrates why zero discharge can lead to more serious environmental problems. Achieving 100% recycling requires reverse osmosis units, which generate huge volumes of non-recyclable waste in the form of water-soluble salts. The decision to abandon the creation of new landfills for toxic waste disposal in favor of deep tertiary treatment of wastewater and maintaining a minimal discharge proved to be a more sustainable solution.

Modernization of Filtration Stations and Flow Separation

Reducing the number of wastewater outlets from nine to two became possible due to a large-scale reconstruction of the wastewater disposal system. The key engineering solution was replacing vertical filters with horizontal ones at a single filtration station. This allowed for an increase in the filtration area and a decrease in its speed, which significantly improved the quality of purification. In addition, the filter wash water was diverted into a separate tertiary treatment cycle with thickeners and filter presses, eliminating the circulation of pollutants within the system.

Innovative Methods: Phytopurification and Biomonitoring

Special attention in the presentation is given to non-standard methods of tertiary treatment of dirty recycling cycles. The enterprise is implementing phytoremediation technologies, using native aquatic plants and bivalve mollusks (zebra mussels) as natural biofilters. Plants effectively accumulate heavy metals and nitrogen-group substances without becoming a source of secondary pollution after dying off. The effectiveness of these measures is confirmed by regular biomonitoring: the species composition of the ichthyofauna in the discharge zone corresponds to the indicators of clean tributaries of the reservoir.

What you will learn from this webinar:

• How to technically implement the separation of clean and dirty recycling water supply cycles?
• Why reducing the filtration speed at treatment facilities yields a greater effect than introducing new reagents?
• How to legally deduct background concentrations of pollutants when calculating discharges?
• Which aquatic plants can effectively purify industrial wastewater from heavy metals?
• How to organize a system of local workshop closure to prevent sulfate discharge?