A novel mixing technology based on regulating biogas pressure was designed as a mixing strategy to solve mass transfer limitation and high energy consumption,which could achieve self-stirring and improve biogas production.A mesophilic fermentation experiment was carried out with co-substrate (vegetable waste and Arundo donax straw).The biogas production,methane content,raw material degradation,and the variation of pH in reactors during the experiment were investigated.The results showed that,when TS concentration of fermentation was 15％,the maximum daily biogas yield of biogas pressure regulating group was 62.55 mL · g-1 VS,which was increased by 29.64％ comparing with the control group;and the cumulative biogas yield in 50 days was 820.47 mL · g-1 VS,which was 2.09 times of control group.The pH was between 7.0 ～ 7.69 and relatively performed stable throughout fermentation.What was more,the methane content of the biogas was up to 79.12％.Meanwhile,the cellulose degradation rate of pressure regulating group was 30.2％,which was about 1.2 times of control group.Therefore,the pressure regulating method could promote mass transfer in dry anaerobic fermentation and improved biogas production.%针对制约厌氧干发酵技术推广应用的传质限制、搅拌能耗高和产气率低等瓶颈问题,文章提出了基于“周期性聚气增压,间歇性喷淋强化传质、定期快速释气泄压”压力调控的干发酵工艺.采用蔬菜废弃物和芦竹秸秆作为混合发酵原料进行中温发酵试验,研究了压力调控下干发酵的产气效果,pH值的变化及原料降解的情况.结果表明:发酵底物浓度为15％时,压力调控组的最大日产气率为62.55 mL·g-1VS,相对其对照组提高了29.64％;经过50 d发酵后累积产气率为820.47 mL·g-1VS,是其对照组的2.09倍;pH值均在7.0 ～7.69之间波动,运行良好,所产沼气中CH4含量高达79.12％;其纤维素降解率达30.2％,约为对照组的1.2倍.表明压力调控可促进干发酵直接产出CH4含量较高的生物天然气.
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