Reagent Removal of Heavy Metals From Waters of Coal Mines and Spoil Tips of the Lviv-Volyn Industrial Mine Region

The article substantiates the efficiency of using chemical (reagent) technologies for the purification of industrial water from mines and spoil tips from heavy metals-toxicants and reducing their ecological hazard. The ecological risk indices of toxicants and their proportion in the overall level of ecological danger of the investigated object were presented. The results of experimental studies, interaction of comparative qualitative indicators of removal of heavy metal ions by inorganic reagents – calcium carbonate and sodium hydroxide were provided. It is shown that the solution of the ecological problem concerning the reduction of the toxicity level of subterminal waters of mines is their treatment with fine calcium carbonate CaCO₃ that converts the heavy metal ions into hardly soluble basic carbonates or heavy metal hydroxides. Positive results concerning the efficiency of the subterminal water treatment of the «Velikomostovskaya» mine of the Chervonograd mining area by calcium carbonate were identified. That indicates a significant reduction of the ecological hazard indicator of the treated wastewater. The content of ions of most heavy metals, which precipitate in the form of basic carbonates at values close to pH = 8.5, was significantly reduced.