Combining Coagulation and Filtration Methods for the Treatment of Laundry Wastewater

Abstract Laundry wastewater containing fabric softeners and detergents is hazardous to the environment and requires treatment before being discharged. The government’s wastewater quality criteria for laundry enterprises and activities are often exceeded by this wastewater due to its high levels of total dissolved solids (TDS), pH, and turbidity. In this study, two treatment methods—coagulation and filtration—were combined. Calcium oxide (CaO) was used as the coagulant in varying amounts (5, 10, 15, and 20 grams). The treated wastewater was then filtered through silica sand, activated carbon, and zeolite. The parameters analyzed were TDS, pH, and turbidity. Results showed that using 20 grams of CaO followed by filtration with zeolite media, was able to reduce turbidity by 99.94%, with the pH and TDS of the laundry waste reaching 8.79 and 1770, respectively. The use of CaO as a coagulant combined with zeolite as a filtration medium is the best combination for treating laundry waste to meet the government’s regulatory standards. Hence, combining coagulation and filtration using these two materials can serve as an affordable and effective method for laundry waste treatment. By implementing this method, the treated laundry waste becomes environmentally friendly.