A responsible approach to water resources management

The Turów plant, due to its location, is situated in an area characterised by higher than average precipitation levels. Part of the precipitation falling at the foot of the Izera Mountains is naturally retained in the Witka Reservoir, located on the Witka River. This reservoir is the main water intake for the Turów plant. Given that the water in the Witka reservoir comes largely from precipitation, the technological processes in Elektrownia Turów use rainwater to a significant extent. The Turów plant uses only surface water for its operations and does not use underground water intakes.

At the Turów plant, the closing of the water cycle in production processes is carried out by diverting used water for treatment and returning it again to production processes.

All sewage from the power plant site is treated in sewage treatment plants: Industrial Sewage Treatment Plant, Sewage Treatment Plant from Wed Flue Gas Desulphurisation System at unit 7, Sewage Sub-treatment Plant from Flue Gas Desulphurisation System at units 4-6, Ash Settling Plants, Sanitary Waste Water Treatment Plant.

Closing the water cycle in production processes by diverting used water for treatment and returning it back to production processes is carried out.

The expansion of the industrial sewage treatment plant at Turów power station began in 2021. Sewage from the Turów plant is discharged into the Miedzianka River. In order to achieve the environmental objective, it must be ensured that the sewage discharged into the river does not deteriorate its condition, thus the sewage parameters must meet the water quality requirements for a mountain stream class. The implemented project will ensure that the environmental objectives are met, thus bringing Elektrownia Turów into compliance with EU and national environmental requirements.

The industrial wastewater treatment plant will be based on modern, high-efficiency membrane technologies – microfiltration and reverse osmosis. The efficiency of reverse osmosis is approx. 96%-98%, meaning that over 96% of all pollutants will be captured in this process. This will be the first in Poland, and one of the few in the European Union, to use this type of technique so extensively in the area of wastewater treatment. As a result of this project, the Turów plant will be the first power station where treated sewage can be returned to technological systems. The new treatment plant will be the largest treatment plant in the Polish power industry, using membrane technologies with a total capacity of approx. 12,000 m3 per day (at the inlet to the industrial wastewater treatment plant). Implementing this investment will have a positive impact on the border river – the Nysa Łużycka.

At Elektrownia Opole, all sewage from the company’s premises is treated in a final treatment plant. Some types of industrial sewage are subject to multi-stage treatment. Industrial and rainwater wastewater is directed to the final mechanical-chemical treatment plant, where it undergoes a coagulation process. Sewage is treated using the activated sludge method in a biological system, also located in the final treatment plant. The treated industrial and domestic sewage is discharged through a common collector to the Odra river.

In order to improve the sedimentation of incoming suspended solids in the raw sewage and to improve and automate the discharge of sludge to the sludge plots, a radial settling tank with an integrated coagulation chamber has been in operation since 2019. The new settling tank increased the operational reliability of the treatment plant and created a capacity reserve for the equipment at the treatment plant. It operates as the primary plant of the wastewater sequence. The design capacity ensures the capture and treatment of the inflow up to the nominal size of 3 200 m³/h and has a hydraulic reserve.

The Dolna Odra power station has an open cooling system and is equipped with facilities for the reduction of pollutants contained in sewage. Depending on the type of wastewater, it is treated in a chemical treatment plant, a biological treatment plant, mechanical treatment plants or neutralised in neutralisers. Depending on the composition of the wastewater, it is treated in one or two facilities. Rainwater and snowmelt from the ward area is treated using settling tanks and separators. In order to improve the sedimentation of incoming suspended solids in the raw sewage and to improve and automate the discharge of sludge to the sludge plots, a radial settling tank with an integrated coagulation chamber has been in operation since 2019. The new settling tank increased the operational reliability of the treatment plant and created a capacity reserve for the equipment at the treatment plant. It operates as the primary plant of the wastewater sequence. The design capacity ensures the capture and treatment of the inflow up to the nominal size of 3 200 m3/h and has a hydraulic reserve.

In order to reduce water consumption and the amount of sewage discharged to water, the water used at the Bełchatów plant is reused in closed internal circuits and is not discharged to water. The power plant does not have a treatment facility. Used process water is used for slagging and making up losses in the hydro-ash cycle. Sanitary wastewater and rainwater or snowmelt are discharged to the wastewater treatment plant located at the KWB Bełchatów Branch.

At the Rybnik plant, all wastewater from the power station premises is treated in the industrial sewage treatment plant and the flue gas desulphurisation system. The Rybnik plan uses closed water circuits wherever possible. The water taken from the intakes is used in internal processes and only when there is no possibility to use it in the power plant installations, it is discharged as wastewater.

In connection with the need to adapt the treatment plant to the requirements of BAT conclusions, the method of sewage treatment using the modern Nalmet preparation was successfully applied.

Since the beginning of its operation, the Bełchatów mine has been carrying out planned and rational activities in the field of water protection. The dewatering of the rock mass is carried out in order to create such a depression that ensures the safe exploitation of the deposit using the open pit method.

The dewatering system of the KWB Bełchatów mine captures both groundwater and surface water in order to dewater the rock mass to a degree that enables the safe exploitation of lignite from the Szczerców Field and Bełchatów Field.

In order to counteract the environmental impact, the mine is carrying out the following projects to reduce the impact of the dewatering of the deposit on the surroundings:

• the use of a deep drainage system using large diameter deep wells, which makes it possible to lower the groundwater table while maintaining the safety of the mining works and limiting the amount of water pumped,
• the use of selective extraction and discharge of pumped water in the pit to reduce the amount of dirty water requiring treatment,
• the use of a multi-stage treatment system for water discharged from excavation dewatering,
• maintaining a proper hydrodynamic system in the area of the „Dębina” salt diapir in order to protect its structure,
• extensive monitoring of the impact of mining activities on the environment, allowing observation of early possible symptoms of deterioration in the condition of a selected environmental element and providing the opportunity to take appropriate preventive measures.

Water from deep drainage is discharged through a system of ditches and canals in quantities and physiochemical parameters that do not exceed the statutory provisions contained in the valid water law permits. Waters discharged into surface watercourses must feature at least class II purity.

In order to protect the water purity of the region’s existing natural watercourses, wastewater management has been solved by the mine’s construction of the following treatment plants:

• Central Sewage Treatment Plant in Rogowiec – mechanical and biological type. It treats domestic/social and rain-industrial types of wastewater. The treatment plant provides wastewater treatment services for external companies,
• Sewage treatment plant in Chabielice – mechanical-biological treatment plant. It treats social and domestic sewage from the facilities of O/Szczerców and provides treatment services for the Municipal Facility in Szczerców.

As part of the surface drainage of the heap, the main part of the rainwater goes into retention and sedimentation fields at the foot of the heap. To intercept some of such water, small retention reservoirs are built on the tops of the heap. These reservoirs are part of the surface drainage of the heap. The water collected in them serves to protect the heap from water erosion (collecting water from drainage ditches). It also serves as a watering hole for animals in the emerging new forest ecosystem of the reclaimed dumps. Such reservoirs have been built on the internal dump of the Bełchatów Field and the external dump of the Szczerców Field, as well as on the external dump of the Bełchatów Field (Góra Kamieńsk), which has been recultivated and fully handed over to the Bełchatów Forest District.

In 2022, the Turów mine branch discharged the following to external watercourses: mine water from surface dewatering of the pit, well water and domestic sewage. The quality of well water allows it to be discharged directly into external watercourses.

Mine water and domestic sewage were treated at 5 on-site sewage treatment plants. Mine water treatment plants at the branch are equipped with the Actiflo system – a highly effective process of suspension reduction.

The parameters regarding the quantity and quality of discharged sewage are regulated by the requirements of valid water law permits held by the branch. The quality and quantity of discharged water and sewage are monitored on an ongoing basis.