Ammoniacal Nitrogen (AN) Degradation Via Coagulation Using Polyaluminum Chloride (PAC) for Matured Leachate

Abstract

Coagulation-flocculation is a commonly used treatment in matured leachate (ML). This study aimed to remove ammoniacal nitrogen (AN) in ML from the Simpang Renggam Landfill Site (SRLS), Johor, by using Polyaluminum Chloride (PAC) as the coagulant. The performance of PAC was evaluated by optimizing the optimal dosage (500 – 4000 mg/L), pH (2 – 8), and settling time (10 – 60 min). The optimal conditions for coagulation-flocculation by using PAC were determined to be at the dosage of 2000 mg/L, pH 7, and a settling time of 20 minutes, achieving 29% AN removal. A Sludge Volume Index (SVI) test was conducted, resulting in 98.66 mL/g, which falls within the good range of SVI values (80-150 mL/g). Compliance with the regulations was not achieved under Malaysia's Environmental Quality Act (EQA) 1974 since the AN concentration for the coagulant remained above 5 mg/L. However, the findings demonstrated that PAC could potentially be effective as a primary mature leachate treatment, as it managed to remove 29% of AN. Thus, this study highlighted the relevance of this method in the treatment of matured leachate.