华南地区稻秸常温干式厌氧发酵试验研究

该文将经过预处理后的稻秸，进行厌氧干式发酵，研究了稻秸发酵过程中的生物气产量、pH值、乙酸及甲烷含量的变化。结果表明，稻秸经过调节C/N和白腐菌预处理后，C/N从37.18降低到28.01，前45d的累积产气量约占总产气量的80.4%；发酵原料总固体产气率为0.457 m³/kg，与常规湿式厌氧发酵相比，不仅提高了池容效率，而且缩短了发酵周期，同时提高了单位原料产气率。发酵液的pH值稳定在6.8～7.5；当发酵前期甲烷含量长期处在较低水平时，可以通过再接种的方法提高甲烷含量。实验结果表明厌氧干发酵产沼气是一种技术上可行的农业废弃物资源化方式，该实验结果为稻秸的大规模生物气化提供重要的工艺设计依据。

Experimental study on dry anaerobic digestion of rice straw at ambient temperature in South China

After pretreated,dry anaerobic digestion technology with zymotic fluid circulated(total solid concentration is about 20%) for straw conversion to biogas was investigated.Biogas production,pH value,concentration of acetic acid and percentage of methane in ambient temperature digestion were tested.The result showed that the C/N adjustment and biological pretreatment reduced C/N from 37.18 to 28.01.The cumulative production in early 45 days was 80.4% of total production.The biogas production achieved(0.457) m~3/kg TS.Compared with wet anaerobic digestion,the dry anaerobic digestion shortened the digestion cycle and increased the biogas production.The pH value in zymotic fluid was stable at 6.8~7.5 that can be accepted in anaerobic digestion.In digestion prophase,when the low percentage of methane continued in long period,inoculating again could increase the quality of biogas.This study could provide useful parameters for the design of large-scale dry anaerobic digester for straw conversion to biogas.