Effect of lysozyme combined with hydrothermal pretreatment on excess sludge and anaerobic digestion  

作　　者：Xiuqin Cao Songyue Li Chaolei Liu 

机构地区：[1]School of Environment and Energy Engineering,Beijing University of Civil Engineering and Architecture,Beijing 100044,China [2]Key Laboratory of Urban Storm water System and Water Environment(Ministry of Education),Beijing University of Civil Engineering and Architecture,Beijing 100044,China

出　　处：《Journal of Environmental Sciences》2025年第1期36-49,共14页环境科学学报(英文版)

摘　　要：Anaerobic digestion(AD)is widely employed for sludge stabilization and waste reduction.However,the slow hydrolysis process hinders methane production and leads to prolonged sludge issues.In this study,an efficient and eco-friendly lysozyme pre-treatment method was utilized to address these challenges.By optimizing lysozyme dosage,hydrolysis and cell lysis were maximized.Furthermore,lysozyme combined with hydrothermal pretreatment enhanced overall efficiency.Results indicate that:(1)When lysozyme dosage reached 90 mg/g TS after 240 min of pretreatment,SCOD,soluble polysaccharides,and protein content reached their maxima at 855.00,44.09,and 204.86 mg/L,respectively.This represented an increase of 85.87%,365.58%,and 259.21%compared to the untreated sludge.Threedimensional fluorescence spectroscopy revealed the highest fluorescence intensity in the IV region(soluble microbial product),promoting microbial metabolic activity.(2)Lysozyme combined with hydrothermal pretreatment significantly increased SCOD,soluble proteins,and polysaccharide release from sludge,reducing SCOD release time.Orthogonal experiments identified Group 3 as the most effective for SCOD and soluble polysaccharide release,while Group 9 released the most soluble proteins.The significance order of factors influencing SCOD,soluble proteins,and polysaccharide release is hydrothermal temperature>hydrothermal time>enzymatic digestion time.(3)The lysozyme-assisted hydrothermal pretreatment group exhibited the fastest release and the highest SCOD concentration of 8,135.00 mg/L during anaerobic digestion.Maximum SCOD consumption and cumulative gas production increased by 95.89%and 130.58%,respectively,compared to the control group,allowing gas production to conclude 3 days earlier.

关 键 词：Excess sludge LYSOZYME Hydrothermal pre-treatment Anaerobic digestion Gas production 

分 类 号：X703[环境科学与工程—环境工程]