Heavy metals: The industry and environmental protection

The results of the study demonstrate the possibility of decontaminating excess active sludge, wastewater sediments, and bottom sediments in natural bodies of water to remove heavy metals by substitution of the heavy metals in the sludge components by calcium. This method creates prospects for utilization of excess sludge and bottom sediments as organomineral fertilizers in agricultural or garden and park landscaping in cities. Combined incorporation of calcium-containing materials in bottom sediments and exposure to a magnetic field enhance the process and increases the degree of extraction of heavy metals. When the excess sludge and sediments are stored in sludge fields, heavy metals migrate into the environment by different paths, i.e., sludge fields do not solve the problem of preventing environmental pollution by heavy metals.