Characteristics of municipal solid waste leachate under hydrothermal treatment

• Main Authors: Khamis, Siti Salwa, Purwanto, Hadi, Salleh, Hamzah Mohd
• Format: Conference Proceeding
• Language: English
• Subjects: Ammonia; Chemical oxygen demand; Hydrothermal treatment; Leachates; Municipal solid waste; Municipal waste management; Nitrogen; Oxidation; Process parameters; Reaction time; Solid waste management; Solid wastes
• ISSN: 0094-243X; 1551-7616
• DOI: 10.1063/5.0111308

Malaysian produce 38,000 tons municipal solid waste releasing 22,420 m3 leachate per day in 2021. Lack of efficient facilities cause leachate treatment in the country very challenging. This paper discusses the treatment of leachate with hydrothermal processing method using an autoclave set up at temperature 100-200 °C, pressure 0.1-1.6 MPa, and reaction time 60-120 minutes. Laboratory studies were conducted to design the hydrothermal processing for leachate treatment and to investigate the effect of setup parameters condition along the process. Leachate characterization such as pH, chemical oxygen demand (COD), and ammonia nitrogen (NH3-N) was carried out before and after the treatment. Parameter set up at 200 °C, 1.6 MPa and 120 minutes of treatment shows the best condition for hydrothermal leachate treatment since the pH has changed from 3.27 to 5.50, COD decreased from 51,000 mg/L to 53 mg/L, and NH3-N decreased from 3496 mg/L to 0.3 mg/L. Hydrothermal leachate treatment is a rapid and green process that save time and operational cost. The results indicate that treatment of leachate employing hydrothermal process set up is a potential method that can be one of the alternatives for leachate treatment.