Removal of Organic Pollutants from Industrial Cleaning Wastewaters Using a Combined Sedimentation and Packed-bed Column Treatment

Abstract

In the present study, organic removal from five industrial cleaning wastewaters generated at a wood-laminate floor industry in Sweden was evaluated using a combined treatment process including sedimentation and a packed-bed column of commercial wood-based activated carbon (WAC). The supernatant obtained from the sedimentation was diluted with tap water until the COD concentration was reached 5 000 mg/L and it was continuously fed through the column by up-flow mode at a constant flow rate of 6 mL/min. The WAC performance at different bed height of 19, 38 and 57 cm was studied. The results showed that the sedimentation process removed about 20%, 24% and 24% of COD, TOC and BOD, respectively and the WAC column was effective in removing COD from the water phase. The treated wastewater volume and service time increased with the bed height increase. The column could treat 19 L of wastewater with the service time of 63.3 h and 30% breakthrough point. The experimental data fitted well with the bed depth-service time (BDTS) model. The increase of wastewater load on solid phase from 20%, 30%, 40% and 50% showed an increase of sorption capacity (No) and decrease of the rate constant (k).