Napier grass (Pennisetum purpureum) is a high yield tropical grass with great potential for anaerobic digestion. Two-phase anaerobic dry digestion (TADD), considered an alternative for anaerobic wet digestion system (AWD) with only front-end leach bed reactor (LBR), is added to existing liquid digester, was tested under different leachate circulations, and was compared with AWD. Leachate circulation frequency in LBR was found to highly influence hydrolysis rate and hence improved overall digestibility of the grass fiber. Additional methane yield of 32.5% was achieved when leachate circulation increased from 1 to 4 times per day and diminished to merely 13.7% more at continuous circulation. A shift in methane generation from leachate digester to LBR as digestion time progressed and important biochemical characteristics were discussed. In AWD, operation at an organic loading of 4 kgVS/m³ d gave the highest methane yield at 145.2 m³/ton_dry, which is 2.3 times higher than TADD due to an advantage in mass transfer in a total wet environment. This work had advanced our understandings on phase separation in anaerobic digestion system and the key methanation performance among dry and wet digestions of the prototypical lignocellulosic biomass.

中文翻译：

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两相干消化系统与湿消化系统中的内皮草（狼尾草）的无氧消化。

内皮草（狼尾草）是一种高产的热带草，具有厌氧消化的巨大潜力。两相厌氧干消化（TADD）被认为是仅前端浸出床反应器（LBR）的厌氧湿消化系统（AWD）的替代品，被添加到现有的液体消化池中，在不同的沥滤液循环下进行测试，并进行了比较与AWD。发现LBR中的渗滤液循环频率对水解速率有很大影响，因此改善了草纤维的整体消化率。当渗滤液循环量从每天1次增加到每天4次时，甲烷的额外收率达到32.5％，而在连续循环时，甲烷的收率则降低了仅13.7％。随着消化时间的进展，甲烷的产生从渗滤液消化池向LBR的转变以及重要的生化特性进行了讨论。在AWD中，³  d在145.2 m ³ /吨_干态下可获得最高的甲烷产量，由于在整个湿润环境中传质的优势，因此比TADD高2.3倍。这项工作使我们对厌氧消化系统中的相分离以及原型木质纤维素生物质的干，湿消化中的关键甲烷化性能有了更深入的了解。