Natural waters and wastewaters often contain heavy metals, e.g., iron. Iron ore mining contaminates groundwater with iron up to 30 maximal permissible concentrations (MPC) as this element gets washed out from rock and soil. Adsorption is the most effective and economically feasible method of additional purification of natural and wastewater from iron. Its efficiency depends on the type of adsorbent. The research objective was to select the most efficient sorption material to eliminate water from iron, as well as to establish the adsorption patterns for different sorbents, thus creating sustainable and effective purification. The study featured carbonaceous sorbent of the SKD-515 grade, mineral sorption materials with aluminosilicate of the AC grade, and silicate-based sorbent of the ODM-2F grade. The porous structure was studied by porometry methods while the surface image was obtained using scanning electron microscopy. Other indicators included equilibrium, kinetics, and dynamics of iron adsorption by various sorbents. The Freundlich and Langmuir equations made it possible to calculate the key adsorption parameters. The Gibbs energy values were obtained from the Langmuir equation and equaled 11.93–20.66 kJ/mol, which indicated the physical nature of the adsorption process. Under static conditions, the sorbents demonstrated a high adsorption capacity with respect to iron, depending on the structure, and could be arranged as AC > SKD-515 > ODM-2F. In SKD-515, iron adsorption occurred in micropores; in AC and ODM-2F, it took place in mesopores. The kinetics of iron extraction showed that the adsorption process was limited by external mass transfer. The research provided a new understanding of iron adsorption by materials of various structures. The conclusions were supported by scanning electron microscopy images. Initial concentration, flow velocity, and loading layer height were studied in dynamics, i.e., during continuous operation of the adsorption column. The system proved extremely effective and reached 99.0% Fe3+ extraction under the following conditions: flow rate = 1 L/min, loading column height = 0.15 m, column diameter = 0.05 m, initial concentration = 0.5 mg/L (5 MPC). The column performance was tested at an initial concentration of iron ions of 50 MPC, which simulated the wastewater treatment at industrial enterprises. This comprehensive study of iron adsorption from wastewater proved the efficiency of the mineral sorption materials with aluminosilicate of AC grade.
The sources of the major pollutants in quarry wastewater are investigated for Kuznetsk Basin coal mines. Various methods of removing those pollutants are a
20 September 2024 in Mining Science and Technology (Russia)
The state of Kuzbass water resources is attracting more and more attention, which is associated with increasing industrial use. The risk of reducing the sanitary reliability of water bodies is due to an increase in the amount of industrial wastewater and the multicomponent nature of their composition. For Kuzbass as a coal-mining region, wastewater treatment of coal mining and processing enterprises is relevant. The data of monitoring reporting, the characteristics of the applied cleaning methods are given in the paper. The most common system of treatment facilities in coal mines, the formation of runoff and problem areas are considered. The sewage receiver is small rivers, the layers are drained by natural drainage, the drainage water is collected in sumps, then it is pumped to the settling ponds by pumps. In the settling ponds, wastewater stays for several days, which leads to the release of suspended particles. After the dam, the treated wastewater is divided into two streams: one is discharged into a reservoir, the other is sent to a storage pond to use this water in the technological process. The possibility of using filtration through artificial filter arrays with a layer consisting of a carbon sorbent at the second stage of purification was studied. The filtering carbon material based on anthracite — Purolat-Standard and coconut charcoal, the raw material for which is a natural material, are analyzed. Adsorption isotherms were used as a criterion for evaluating the adsorption capacity of materials. The sorption capacity of coconut charcoal with respect to iron ions when extracted from individual model solutions, according to the experiment, was 0.54 mg/g. The content of manganese in the solution after adsorption on coconut charcoal decreased according to the experimental data, and the adsorption value was 147 mg/g.