Effect of temperature on removal of COD and TSS from artificial river water by mudballs made from EM4, rice bran and clay

Abstract

In Indonesia surface water is often polluted by domestic waste causing degradation of river water quality. The use of activated Effective Microorganism Solution (EMS) mixed with rice bran or wheat bran, as well as soil and shaped into mudballs has in recent years shown promise as a direct method to improve quality of polluted river water. This study examined the effect of temperature on removal of COD and TSS by mudballs made from activated EM4 solution, rice bran and clay soil. Batch experiments treating artificial river water by the mudballs were conducted at temperatures 25°C and 30°C with the artificial river water having initial levels of 120 mg/L COD and 100 mg/L TSS. Efficiency removals of COD by 2.5 cm ø mudballs at 25°C and 30°C were 66.7% and 59.4%, whereas that of TSS were 100% and 99.7% respectively. TSS sorption by the mudballs appears to better fit the Langmuir than the Freundlich isotherm models. At 25°C and 30°C, maximum sorption (Qm) of TSS is 6.89 mg/g and 7.52 mg/g; Langmuir constant (KL) is 0.0196 L/mg and 0.0168 L/mg, while equilibrium parameter (RL) is 0.338 and 0.373 respectively. Statistical hypothesis testing of the experimental data suggests that at α=0.05, temperature affects removal efficiency of COD but not that of TSS.