There are approx. 250 coal waste dumping grounds in Poland, yet there are countries in which this number is even higher. One of the largest sites for depositing mining and power plant waste in the Upper Silesian Coal Basin is the Przezchlebie dumping ground. In the article, it is considered as a secondary deposit of raw materials. An assessment of mining waste collected on the Przezchlebie dumping ground was carried out in terms of its impact on the environment and the possibility of its use. Mining waste samples were tested to determine their chemical composition. Physicochemical properties and chemical compositions of water extracts obtained from the investigated waste and groundwater in the vicinity of the dumping ground were analyzed. Due to the fire hazard resulting from the natural oxidation process of chiefly carbonaceous matter and pyrite, the thermal condition of the dumping ground was assessed. The results of the obtained tests confirmed the slight impact of mining waste deposited on the Przezchlebie dumping ground on the environment. The chemical composition, low radioactive activity of waste itself and the results of water extract tests referred to the permissible values according to the Polish Journal of Laws allow for multi-directional waste management. Due to the significant carbon content, the risk of self-ignition poses a significant threat on the dumping ground. Re-mining of the dumping ground and the recovery of raw materials, including coal contained in waste, will eliminate the risk of fire, allowing for a wider use of waste and, at the same time, will allow for other benefits, e.g. in the form of financial resources and the possibility of managing the dumping ground area.
There are a huge number of objects constituting a storage place of coal mining waste in the coal basins in Poland and around the world. The article is a continuation of the study on the possibilities of using raw materials deposited on the coal mining waste dumping grounds on the example of the Przezchlebie dumping ground. The possibility of coal recovery from mining waste located on the dumping ground was analyzed. Tests on the quality parameters of waste were carried out, i.e. moisture and ash content, as well as the calorific value of raw waste. The relatively high calorific value and low ash content in the waste served as the basis for further tests related to the separation of coal. Tests on the mining waste enrichment using the complex based on the K-102 Komag pulse separator were carried out. As a result of coal separation, 7.66% of concentrate was obtained (in relation to feed) with the calorific value of 26.16 MJ/kg and ash content of 19.96%. Apart from mining waste, power plant waste (fly ash) can also be found on the dumping ground. They were subjected to tests for the possibility of using them in the production of construction materials, especially concrete and cement. Fly ash from the Przezchlebie dumping ground was classified as silica ash and it was found that it meets the requirements of Polish standard, except for the fineness of 42%. The separation of coal will eliminate the fire hazard on the dumping ground. A possible scenario of managing waste material on a dumping ground, which can be implemented in similar facilities, has been presented.