Management of water resources

At the same time, water is required for the electrolytic copper production process. It is used, among others, for enrichment (flotation) of ore, hydrotransport of waste, and also in the core production line in the smelters. These interdependencies are shown in the graph below:

Three underground copper mines extract the ore at depths of 400-1350 m. These are the Lubin Mine Division, the Rudna Mine Division and the Polkowice-Sieroszowice Mine Division. Due to the constant inflow of water from the rock mass into the mines, saline mine water is pumped to the surface.

Copper ore processing in ore enrichment plants and, in particular, grinding and flotation require the supply of significant quantities of process water. Water from mine drainage accounts for only part of this demand. The remaining water is supplied by the Tailings Plant from the Żelazny Most Tailings Storage Facility through pipelines on the surface, which form a mine-process water circulation network.

In 2022, the average monthly consumption of process flowback water at the Concentrator Division was approximately 12,821,520 m³ of which:

In KGHM Polska Miedź S.A., approximately 150 million m³ of water per year is recycled to the ore enrichment process. Only water from mine drainage and recycled water from the Żelazny Most Tailings Storage Facility is used in the enrichment process. This enables surface and ground water, one of the most valuable natural resources, to be saved.

Since there is a constant inflow of mine water and rainwater into the system, excess water must be removed. The effluent/mine process water is discharged from KGHM Polska Miedź S.A.’s operations in compliance with the applicable law and the provisions of the water rights permit, taking into account the hydrological conditions of the Odra River, which means that the volume of discharge is adjusted daily to the water level in the river and its chemical characteristics. The retention and dosing system operating at KGHM Polska Miedź S.A. allows the discharge of water into the Odra River to be fully controlled and supervised. As a result, we can stop the discharge of effluents when the water level in the receiver is low. In addition, we strictly adhere to the requirement to regulate the salt load in the effluent so that the sum of chlorides and sulphates in the river water after mixing with the effluent does not exceed 1,000 mg/l. A retention and dosing system also makes it possible to periodically stop the discharge of effluent. This possibility was used in July and August 2022, when a state of emergency was declared on the Odra River and certain restrictions were imposed on the use of its waters.

The Legnica Copper Smelter and Refinery and the Głogów Copper Smelter and Refinery consume significant amounts of water (approximately 11 million m³ per year), which is supplied by Energetyka Sp. z o.o. The company supplies water drawn from the Kaczawa river to the Legnica Copper Smelter and Refinery and from the Odra river to the Głogów Copper Smelter and Refinery.

The water used in production processes is routed back to Energetyka for treatment. Industrial effluent treatment plants operating for the smelters specialise in the removal of heavy metals, including arsenic, mercury and cadmium compounds, which are particularly problematic.

The effluents treatment technology relies mainly on neutralisation processes supported by coagulants and flocculants. Because of the high quality of effluents, approximately 30% of the global stream is reused for production processes in the technological processes of the smelters. Approximately 8 million m³ of the remaining treated effluents is discharged to the Odra river (in the case of the Głogów Copper Smelter and Refinery) and to the Pawłówka stream, which feeds the Kaczawa river (in the case of the Legnica Copper Smelter and Refinery). The effectiveness of treatment of effluents transferred to Energetyka and the metal loads discharged to the environment are presented in the table below.

The Cedynia Copper Wire Rod Plant division is supplied with water for human consumption and for technological purposes. The Orsk intake is a source of water for drinking purposes. Two wells – 1z and 2z – are currently in operation. The Chełm intake wells supply the plant with water for technological purposes.

Wastewater from the area of the copper wire rod plant hall (including used process emulsions) is directed to the oily effluents tanks located in the vicinity of the Power Station building. The effluents collected in the tanks are processed entirely in a VACUDEST vacuum demulsifier.

The sanitary and rainwater-industrial effluents captured are directed to the effluents treatment plant, where they are treated in the sanitary effluents treatment line and the rainwater-industrial effluents treatment line. Treated sanitary and rainwater-industrial effluents are mixed and discharged via a common discharge collector into the Odra River. Since 2021, part of the stream of treated rainwater and effluents from filter flushing at the Water Treatment Plant has been returned for reuse in the cooling circuits. In 2022, the volume reached 8,433 m³.