Optimation of poly aluminium chloride (PAC) and activated carbon on the laboratory wastewater treatment process in pretreatment sedimentation pond

Abstract

The operational process of the service laboratory produces wastewater that cannot be disposed directly but must be treated before being discharged into the environment. The optimal treatment process needs to be determined based on the characteristics of the wastewater produced. This study will determine the optimization of the laboratory waste treatment process in the initial settling basin by comparing the addition of coagulants and activated carbon. Wastewater generated from the operational process of the laboratory was collected from the initial settling basin, then its characteristics were determined including pH, turbidity, TSS, TDS, surfactane as MBAS, ammonia, Total Fe and Mn. Wastewater was added with Poly Aluminum Chloride (PAC) coagulant with a concentration of 50, 100, 200, and 300 ppm. As a comparison, the addition of 20, 40, 60 and 80 grams of activated carbon was also carried out in one liter of wastewater. The best results were the addition of 50 ppm PAC was able to reduce the turbidity value up to 87.2%, TSS 83.3%, Mn metal 70.57% and Fe 60.11%. While the addition of 80 grams of activated carbon is able to restore the pH value to neutral and reduce the MBAS content to 83.62%. Furthermore, the addition of PAC and activated charcoal has no significant effect on reducing levels of ammonia and TDS. The results showed that the addition of PAC can be done in the initial basin and combined with the addition of activated carbon in the subsequent processing basin.