Waste materials and composites as a trickling filter filling

Two variants (preliminary stage and main stage) of the experiment aiming to verify the possibility of using waste materials and composites for septic tank effluent (STE) treatment were investigated. The hydraulic load of filters during main stage was about two times lower than during preliminary stage. The aim of this study was to examine the mechanical and biological treatment efficiencies of four waste materials: polyethylene Raschel mesh (PERM), wood-polymer composite (WPC), cut plastic straws (CPS) and polyethylene (PE). Considering that the used STE was hardly biodegradable, the removal efficiencies of the used materials were relatively high. During main stage for PERM the removal efficiencies of chemical oxygen demand (COD), ammonium nitrogen (NNH4), total phosphorus (Ptot) and total suspended solids (TSS) were 84.6%, 92.8%, 24.5% and 83.6%, respectively. For CPS, efficiencies for COD, NNH4, Ptot and TSS were 58.8%, 40.2%, 43.1% and 84.7%, respectively. For WPC, efficiencies for COD, NNH4, Ptot and TSS were 60.2%, 51.8%, 44.1% and 85.2%, respectively. For PE, efficiencies for COD, NNH4, Ptot and TSS were 46.9%, 30.0%, 43.7% and 85.3%, respectively. The technology used in this study was relatively simple. For maximum effectiveness in wastewater reuse (e.g., for irrigation), mechanical pre-treatment should be performed.