Anaerobic digestion of pomegranate shells was conducted in 25 L bioreactor operating at 35±0.5°C. The digester showed a reasonable amount of biogas (0.71 m³/kg VS fed) and methane (55.7%) with stable pH and acid: alkali profiles when operated at organic loading rate (OLR) from 1.0 to 3.0 kg VS/day/m⁻³. The reactor exhibited stable performance with methane yield of 0.44 m³/kg VS fed and reduction of 38.5% volatile solids (VS) As organic loading rate increased to 3.5 kg VS/day/m⁻³, accumulation of volatile fatty acid (VFA; 2797 ppm), mainly propionic acid (1617 ppm) was noticeable. The digester turned sour (pH 4.32) with lower biogas (2.5 Ld⁻¹) and methane (30.80%) production, reflecting the case of overloading. Reversal of organic loading rate from 3.5 to 3.0 kg VS/day/m⁻³ gradually restored the upset anaerobic digester to normal profile in 4 weeks as judged from a gradual increase in biogas (6.5 Ld⁻¹) and methane (58.4%).

中文翻译：

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使用有机负载法从石榴壳中回收用于生产沼气的酸性厌氧消化池

石榴壳的厌氧消化是在25 L生物反应器中以35±0.5°C进行的。该消化池显示出合理量的沼气（0.71 m ³ / kg V​​S进料）和甲烷（55.7％），具有稳定的pH值和酸：当有机负荷率（OLR）为1.0至3.0 kg V​​S / day / m时，碱分布⁻³。反应器表现出稳定的性能，进料的甲烷产率为0.44m ³ / kg V​​S，并且减少了38.5％的挥发性固体（VS）。随着有机负荷速率增加至3.5kg VS / day / m ^-3，挥发性脂肪酸（VFA； H； H）的累积。 2797 ppm），主要是丙酸（1617 ppm）。消化池变酸（pH 4.32）且沼气较低（2.5 Ld ^-1）和甲烷（30.80％）的产生，反映了超载的情况。从沼气（6.5 Ld ^-1）和甲烷（58.4％）的逐渐增加判断，有机负荷率从3.5 kg V​​S / day / m ^-3反转为4周即可使厌氧消化池恢复正常状态。