Organic matter removal via activated sludge immobilized gravel in fixed bed reactor

In this study, the adsorption capability of the activated sludge immobilized gravel as a low-cost and efficient adsorbent to remove organic matter in terms of chemical oxygen demand (COD) from synthetic wastewater was investigated using fixed bed columns. The effects of parameters including column pack height and influent COD concentrations on removal efficiencies were assessed through breakthrough curves. It was found that the removal efficiency increased when fixed bed height was increased and influent COD concentration was decreased. The maximum COD removal rate of 36.35%, was obtained for a medium-strength wastewater sample with 1166 mg/L of COD concentration when the bed height was 2 cm, and the flow rate was 11 mL/min. Activated sludge immobilized gravel can be utilized as a low cost bio-filter to remove organic material from wastewater.