EFFECTIVENESS OF WASTEWATER POST-TREATMENT IN FILTER COLUMNS WITH THE USE OF MINERAL MATERIALS

Based on the assumptions of the circular economy model and sustainable development, we are currently looking for natural and ecological materials in terms of wastewater treatment of pollutants. This article presents the research of three mineral materials – lava rock (LR), lightweight sintered aggregate (LSA) and lightweight clay aggregates (LCA) used as filling of filtration columns for the treatment of real wastewater. The filtration process was carried out under various hydraulic loads in two columns, one of which was additionally supported by the aeration process. The post-treated sewage was characterized by the following parameters: COD (chemical oxygen demand), TOC (total organic carbon), phosphate phosphorus (P-PO4), total nitrogen (TN) and total phosphorus (TP). Among the hydraulic loads applied, the most optimal loads were OhI = 0.25 m3/(m2·h). Certyd turned out to be the most effective with supporting filtration with the aeration process in removing organic compounds (reduction of 65.1% COD and 38.2% TOC at OhI). Lava rock seems to be a promising material reactive in terms of removal of biogenic compounds such as nitrogen (efficiency 23.8% at OhI) and phosphorus (64.2% reduction of TP at OhI) and organic compounds (21.4% reduction of TOC at OhI in conditions without aeration). LCA shows the best efficiency in sorption of phosphorus compounds (41.6% reduction of TP at OhI) and organic compounds (21.4% TOC reduction at OhI under non-aerated conditions).