温度对餐厨垃圾厌氧发酵产氢的影响

Temperature Effect on Bio-hydrogen Production from Kitchen Waste

通过批式试验探讨了温度对餐厨垃圾厌氧发酵产氢的影响.结果表明:接种厌氧污泥在未经高温驯化(50℃)时直接进行高温厌氧发酵产氢,产氢效果不佳.中温(35℃)驯化1 d后进行产氢实验,与在室温(25℃)条件下所获氢气产率无明显差别.二者氢气的最大体积分数分别是36.8%和37.2%,比氢气产率分别是每克挥发性固体(VS)63.5 ml和每克VS 63.1 ml.但中温条件下体系的反应速率较室温更快,二者根据Gompertz方程得到的产氢速率分别为每克VS15.6 ml.h-1和4.8 ml.h-1,同时反应的停滞时间比室温条件下缩短了9.7 h.对餐厨垃圾产氢前后液相指标(pH,m(VS)/m(总固体,TS),ρ(溶解化学需氧量,SCOD),监测结果表明:酸化过程是反应的限速步骤而非水解过程.因此,建议餐厨垃圾厌氧发酵产氢过程应控制在中温(35℃)下进行比较合理.

A study is made of the temperature effect on anaerobic hydrogen production from kitchen waste in test scale. Results show that low hio-hydrogen production performance achieves at 50℃ in the fermentation with the sludge without incubation. Accumulative hydrogen production at 35℃ and 25 with one-day incubation（35℃ ）sludge is close, and the maximum volume concentrations are 36.8 %, 37.2% and specific hydrogen production rates are 63.5 ml and 63.1 ml per gram of volatile solid （VS）, respectively. However, the anaerobic bio-hydrogen production speed at 35℃ is ohviously faster than that of 25℃;, with Gompertz equation simulated bio-hydrogen production rate of 15.6 and 4.8 ml·h^-1 per gram VS, respectively. At the same time, fermentation lag time at 35℃ is 9.7 h shorter than that at 25℃. It can be induced that the acidization instead of the hydrolysis is the limit phase in anaerobic bio-hydrogen production form kitchen waste at 25℃ and 35℃ with system parameters analysis, such as pH, m （VS）/m （TS） （ total solid）, ρ（soluahle chemical oxygen demand, SCOD）. As a result, middle temperature（35℃ ）is beneficial to the anaerobic bio-hydrogen production from kitchen waste in comparison with high temperature（50℃ ）and ambient temperature（25℃ ）.