Treatment of laundry wastewater using chemically treated sugarcane bagasse

Abstract

Laundry wastewater constitutes of detergent compounds, bleaching agent, textile color pigments and dirt. These compounds are hazardous once discharged into the water source without proper treatment due to the adverse effects on the aquatic life in the freshwater bodies. This fixed-bed column adsorption study using the natural biomass from chemically treated sugarcane bagasse is proven to be effective for the removal of constituents present in the laundry wastewater. The synthetic laundry wastewater was prepared in the laboratory from a powder type of detergent with a concentration of 50mg/L and 250mg/L to be further used in the adsorption process. The characteristics of the synthetic laundry wastewater were analyzed by the turbidity, pH, dissolved oxygen (DO) and chemical oxygen demand (COD). The fixed-bed column experiment with the treated sugarcane bagasse was conducted under different parameters such as the effect of pH, initial concentration and bed height. The best removal efficiency was observed at a bed height of 10 cm with a concentration of 50 mg/L is 65%, followed by 33% and 20% for bed heights of 4 and 2 cm respectively. As for the concentration of 250 mg/L, the best removal efficiency was at a bed height of 10 cm which was found to be 58% followed by 26% and 17% removal for a bed height of 4 cm and 2 cm respectively. The kinetics of the adsorption was investigated using the kinetic models of Thomas and Yoon-Nelson. The experimental results fitted well on the Thomas model and Yoon-Nelson which showed a high linear regression value greater than 0.9. These results prove that chemically treated sugarcane bagasse is an effective low-cost adsorbent for reducing turbidity, pH, COD and increasing the DO concentration.