Response surface methodology (RSM) based on a Box-Behnken Design (BBD) was applied to optimize the thermal-alkaline pre-treatment operating conditions for anaerobic digestion of flotation scum in food waste leachate. Three independent variables such as thermal temperature, NaOH concentration and reaction time were evaluated. The maximum methane production of 369.2 mL CH4/g VS was estimated under the optimum conditions at 62.0°C, 10.1% NaOH and 35.4 min reaction time. A confirmation test of the predicted optimum conditions verified the validity of the BBD with RSM. The analysis of variance indicated that methane production was more sensitive to both NaOH concentration and thermal temperature than reaction time. Thermal-alkaline pretreatment enhanced the improvement of 40% in methane production compared to the control experiment due to the effective hydrolysis and/or solubilization of organic matters. The fractions with molecular weight cut-off of scum in food waste leachate were conducted before and after pre-treatment to estimate the behaviors of organic matters. The experiment results found that thermal-alkaline pre-treatment could reduce the organic matters more than 10kD with increase the organic matters less than 1kD.

• 이동영(수원대학교 토목공학과·하천환경기술연구소) | Dong-Young Lee (Dept. of Civil Eng., The University of Suwon･Institute of River Environmental Technology)
• 최재민(수원대학교 토목공학과·하천환경기술연구소) | Jae-Min Choi (Dept. of Civil Eng., The University of Suwon･Institute of River Environmental Technology)
• 김정광(수원대학교 토목공학과·하천환경기술연구소) | Jung-Kwang Kim (Dept. of Civil Eng., The University of Suwon･Institute of River Environmental Technology)
• 한선기(한국방송통신대학교 환경보건학과) | Sun-Kee Han (Dept. of Environ. Health, Korea National Open University)
• 이채영(수원대학교 토목공학과·하천환경기술연구소) | Chae-Young Lee (Dept. of Civil Eng., The University of Suwon･Institute of River Environmental Technology) Corresponding author