Environmental and Economic Evaluation of Downflow Hanging Sponge Reactors for Treating High-Strength Organic Wastewater (original) (raw)

This study evaluated the performance of a downflow hanging sponge (DHS) in reducing the concentrations of chemical oxygen demand (COD), ammonia (NH3), total suspended solids (TSS), and total dissolved solids (TDS) in high-strength organic wastewater (HSOW). The DHS unit was composed of three segments connected vertically and operated under different organic loading rates (OLRs) between 3.01 and 12.33 kg COD/m3sponge/d at a constant hydraulic retention time (HRT) of 3.6 h. The results demonstrated that the DHS system achieved COD, NH3, TSS, and TDS removal efficiencies of 88.34 ± 6.53%, 64.38 ± 4.37%, 88.13 ± 5.42%, and 20.83 ± 1.78% at an OLR of 3.01 kg COD/m3sponge/d, respectively. These removal efficiencies significantly (p < 0.05) dropped to 76.39 ± 6.58%, 36.59 ± 2.91%, 80.87 ± 5.71%, and 14.20 ± 1.07%, respectively, by increasing the OLR to 12.33 kg COD/m3sponge/d. The variation in COD experimental data was well described by the first-order (R2 = 0.927) and modified Stover–K...