Department of Civil Engineering, The University of Western Ontario, London, Ontario, Canada.
Bioresour Technol. 2012 May;111:122-6. doi: 10.1016/j.biortech.2012.02.019. Epub 2012 Feb 14.
A comparative evaluation of single-stage and two-stage anaerobic digestion processes for biomethane and biohydrogen production using thin stillage was performed to assess the impact of separating the acidogenic and methanogenic stages on anaerobic digestion. Thin stillage, the main by-product from ethanol production, was characterized by high total chemical oxygen demand (TCOD) of 122 g/L and total volatile fatty acids (TVFAs) of 12 g/L. A maximum methane yield of 0.33 L CH(4)/gCOD(added) (STP) was achieved in the two-stage process while a single-stage process achieved a maximum yield of only 0.26 L CH(4)/gCOD(added) (STP). The separation of acidification stage increased the TVFAs to TCOD ratio from 10% in the raw thin stillage to 54% due to the conversion of carbohydrates into hydrogen and VFAs. Comparison of the two processes based on energy outcome revealed that an increase of 18.5% in the total energy yield was achieved using two-stage anaerobic digestion.
采用稀酒糟对单级和两级厌氧消化工艺进行了生物甲烷和生物氢气生产的对比评估,以评估在厌氧消化中分离产酸和产甲烷阶段对其的影响。稀酒糟是乙醇生产的主要副产物,具有高总化学需氧量(TCOD)为 122 g/L 和总挥发性脂肪酸(TVFA)为 12 g/L 的特点。两级工艺的最大甲烷产量为 0.33 L CH 4 /gCOD(添加)(STP),而单级工艺的最大产量仅为 0.26 L CH 4 /gCOD(添加)(STP)。由于碳水化合物转化为氢气和 VFA,酸化阶段的分离将 TVFA 与 TCOD 的比例从原始稀酒糟中的 10%提高到 54%。基于能量产出对两种工艺进行比较的结果表明,两级厌氧消化可使总能量产量提高 18.5%。