Optimization of mixing ratio, shaking speed, contact time, and pH on reduction of Chemical Oxygen Demand (COD) and Ammoniacal Nitrogen (NH3-N) in leachate treatment

When the inevitable generation of waste is considered as hazardous to health, damaging ecosystem to our environment, it is important to develop an innovative technologies to remediate pollutant sources for the safety and environmental protection. The development of adsorption technique for the reduction of extremely effective pollutants in this regard. Green mussel and zeolite mixing media were investigated for the reduction of the concentration of organic constituents (COD) and ammoniacal nitrogen from leachate. The leachate treatability was analyzed under various stages of treatment parameter, namely mixing ratio, shaking speed, contact time, and pH. Both adsorbent were sieve values in between 2.00-3.35 mm particle size. The optimum pH, shaking speed, contact time, and mixing ratio were determined. Leachate samples were collected from influent untreated detention pond at Simpang Renggam landfill site in Johor, Malaysia. The result of leachate characterization properties revealed that non-biodegradability leachate with higher concentrations of COD (1829 mg/L), ammoniacal nitrogen (406.68 mg/L) and biodegradability value (0.08) respectively. The optimal reduction condition of COD and ammoniacal nitrogen was obtained at 200 rpm shaken speed, 120 minute shaken time, optimum green mussel and zeolite mix ratio was 2.0:2.0, and pH 7. The isothermic study of adsorption shows that Langmuir is best suited for experimental results in terms of Freundlich model. The mixing media also provided promising results to treating leachate. This would be greatly applicable in conventionally minimizing zeolite use and thereby lowering the operating cost of leachate treatment.Implications: The concentration of organic constituents (COD) and ammoniacal nitrogen in stabilized landfill leachate have significant strong influences of human health and environmental. The combination of mixing media green mussel and zeolite adsorbent COD and ammoniacal nitrogen reduction efficiency from leachate. This would be greatly applicable in future research era as well as conventionally minimizing high cost materials like zeolite use and thereby lowering the operating cost of leachate treatment.