低温冰冻预处理对水稻秸秆厌氧发酵产气性能的影响

以水稻秸秆为厌氧发酵原料，在中温（37 ℃）湿式批次发酵条件下，考察了低温冰冻预处理在不同温度（-5，-18，-40，-60 ℃）和不同时间（12，24，36 h）下对水稻秸秆厌氧发酵产气性能影响。实验结果表明:低温冰冻预处理均显著增加了秸秆溶出物COD含量，其中D3处理与对照相比增加了7.65倍。低温冰冻预处理显著降低了木质素含量，降低幅度为16.36%~59.88%。在预处理冰冻温度为-5，-18，-40 ℃下，水稻秸秆厌氧发酵TS产气率和甲烷含量随着预处理时间增加而提高。其中，-60 ℃，24 h处理的厌氧发酵TS产气率与-60 ℃，36 h处理的甲烷含量最高，相较于对照组分别提高了96.46%和209.30%。

GAS PRODUCTION PERFORMANCE OF RICE STRAW ANAEROBIC FERMENTATION BY CRYOGENIC FREEZING PRETREATMENT

The rice straw was used as the raw material for anaerobic fermentation. Under the wet batch fermentation conditions with medium temperature (37 ℃), the low temperature freezing pretreatment was investigated at different temperatures (-5, -18, -40, -60 ℃) and times (12, 24, 36 h), to discover the effect of time on the gas production performance of rice straw anaerobic fermentation. The experimental results showed that low temperature freezing pretreatment significantly increased the COD content of straw dissolution, and D3 treatment increased by 7.65 times, compared with the control. Low temperature freeze pretreatment significantly reduced the lignin content by 16.36%~59.88%. Under the pretreatment of -5 ℃, -18 ℃, -40 ℃ freezing temperature, the gas production rate and methane content of rice straw anaerobic fermentation increased with the extension of pretreatment time. Among them, gas production rate of D2 treatment and methane content of D3 treatment was the highest, increased by 96.46% and 209.30% compared with the control group.