不同湿热预处理条件对餐厨垃圾厌氧发酵产氢的影响

采用湿热水解技术处理餐厨垃圾,研究不同湿热预处理温度与时间下餐厨垃圾w(VS)(VS为挥发性固体)、ρ(CODs_Cr)(CODs为溶解性化学需氧量)、ρ(TOC)、ρ(TN)等指标的变化,以评价湿热预处理对餐厨垃圾厌氧产氢效能的影响. 在此基础上,结合厌氧产氢动力学分析,确定厌氧发酵产氢的最佳湿热预处理条件. 结果表明:湿热预处理温度、时间对餐厨垃圾可浮油脱出量、w(VS)具有显著影响. 餐厨垃圾湿热预处理后ρ(CODs_Cr)、ρ(TOC)、ρ(TN)变化情况与w(VS)呈负相关. 餐厨垃圾经90℃湿热预处理30min后,可浮油脱出量为37.5mL/kg,w(VS)/w(TS)为95.12%,最大比产氢量达242.1mL/g,最大产氢速率为12.46mL/h,累积产氢率达0.88mol/mol,厌氧产氢启动时间为12.85h. 说明对餐厨垃圾进行适度的湿热预处理可有效提高有机物溶解性与生物可利用效率,进而提高厌氧发酵累积产氢量与产氢速率. 综合能耗、产出等因素,湿热预处理温度90℃,处理时长30min,为餐厨垃圾厌氧发酵产氢的最佳湿热预处理条件. 

Effect of Hydrothermal Pretreatment for Kitchen Waste on Anaerobic Fermentation Biohydrogen Production

The anaerobic fermentation biohydrogen production potential and variation of VS, CODs_Cr, TOC, TN of kitchen wastes (KW) was investigated under different temperature and time on hydrothermal pretreatment. The kinetic hydrogen production was analyzed to obtain the best hydrothermal operation parameters on anaerobic fermentation biohydrogen production. The results showed that the content of floatable oil and VS were significantly affected by temperature and time of hydrothermal pretreatment significantly. The levels of TOC, TN and CODs_Cr changes were negatively correlated with content of VS. The degree of floatable oil and content of VS of 90℃-30min treatment were 37.5mL/kg and 95.12%, respectively. The special hydrogen production rate, maximum hydrogen production rate and accumulate hydrogen yield were 242.1mL/g, 12.46mL/h and 0.88mol/mol, respectively under of 90℃-30min hydrothermal pretreatment. The lag-phase time of biohydrogen production process was 12.85h, which showed that the solubility and bioavailability of organic efficiency could be enhanced by a modest hydrothermal pretreatment, and then the hydrogen production rate and accumulation hydrogen yield. To synthesize the consideration of energy consume and production, the optimum operation parameters of hydrothermal pretreatment was 90℃ for 30min for KW anaerobic fermentation biohydrogen production.