title: Effect of Ca(OH)2 pretreatment on extruded rice straw anaerobic digestion.
abstract: It has been proven that extrusion can change the structure of rice straw and increase biogas production, but the effect of a single pretreatment is limited. Ca(OH)2 pretreatment was used to enhance the enzyme hydrolysis and biogas production of extruded rice straw. After Ca(OH)2 pretreatment, the glucose and xylose conversion rates in enzymatic hydrolysis increased from 36.0% and 22.4% to 66.8% and 50.2%, respectively. The highest biogas production observed in 8% and 10% Ca(OH)2 pretreated rice straw reached 564.7mL/g VS and 574.5mL/g VS, respectively, which are 34.3% and 36.7% higher than the non-Ca(OH)2-loaded sample. The Ca(OH)2 pretreatment can effectively remove the lignin and increase the fermentable sugar content. The structural changes in the extruded rice straw have also been analyzed by XRD, FTIR, and SEM. Considering all of the results, an 8% Ca(OH)2 loading rate is the best option for the pretreatment of extruded rice straw.
authors.affiliation: Key Laboratory of Yangtze Water Environment of Ministry of Education, State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Gu
authors.affiliation: Key Laboratory of Yangtze Water Environment of Ministry of Education, State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China.
authors.forename: Yalei
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Key Laboratory of Yangtze Water Environment of Ministry of Education, State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China. Electronic address: zhouxuefei@tongji.edu.cn.
authors.forename: Xuefei
authors.initials: X
authors.lastname: Zhou
mesh_terms: D000693:Anaerobiosis / Q000187:drug effects; D056804:Biofuels / Q000032:analysis; D002126:Calcium Hydroxide / Q000494:pharmacology*; D002482:Cellulose / Q000378:metabolism; D003460:Crystallization; D005947:Glucose / Q000378:metabolism; D006868:Hydrolysis / Q000187:drug effects; D008031:Lignin / Q000737:chemistry; D012275:Oryza / Q000737:chemistry*; D012037:Refuse Disposal / Q000379:methods*; D014866:Waste Products / Q000032:analysis*; D014994:Xylose / Q000378:metabolism
chemical_list: D056804:Biofuels; D014866:Waste Products; D002482:Cellulose; D008031:Lignin; D014994:Xylose; D005947:Glucose; D002126:Calcium Hydroxide
keywords: Biogas production; Ca(OH)(2) pretreatment; Enzyme hydrolysis; Extrusion pretreatment; Rice straw