Heavy metals and sulfate removal from water by means of Al powder-cement-based filtration

Al powder-cement-based filters used to treat contaminated water from a coal mining area were designed and tested. Several of these multicomponent filters, containing quartz sand, Portland cement and water, as well as additional components (Al powder, CaO and CaSO 4 ) in various mass proportions have been prepared. In this respect, an exhaustive analysis of the impact of the individual components on the properties of the filters was conducted to evaluate their efficiency in the removal of heavy metals and SO 42– . Moreover, additional filter properties such as water permeability, uniaxial compressive strength and resistance to frost were also considered. The information gathered revealed that the designed filters pose high efficiency in respect of heavy metal removal (Cu, Cr, Ni, Co, Zn) and also exhibit proper water permeability and high mechanical strength. Based on this analysis, an optimal filter composition is provided. The results reported herein suggest that Al powder-cement-based filters are environmentally sustainable and cost effective for the treatment of water from industrial sites even in cold weather conditions.