Tatara Masahiro, Yamazawa Akira, Ueno Yoshiyuki, Fukui Hisatomo, Goto Masafumi, Sode Koji
Group of Environmental Engineering and Bioengineering, Kajima Technical Research Institute, Chofu-shi, Tokyo 182-0036, Japan.
Bioprocess Biosyst Eng. 2005 Apr;27(2):105-13. doi: 10.1007/s00449-004-0387-8. Epub 2004 Nov 24.
In order to maximize the efficiency of methane fermentation on short-chain fatty acids, growth media containing acetic acid and butyric acid as major carbon sources were supplied to a thermophilic down-flow anaerobic packed-bed reactor. The organic loading rate (OLR) to the reactor ranged from 0.2 to 169 kg-dichromate chemical oxygen demand(CODcr)/m(3)-reactor/day, corresponding to a hydraulic retention time (HRT) of between 1.4 h and 20 days. Stable methane production was maintained at HRTs as short as 2 h (OLR=120 kg-CODcr/m(3)/day), with the short-chain fatty acids in the feed almost completely removed during the process. The apparent substrate removal efficiency, determined from the total CODcr values in the influent and effluent, was 75% at short HRTs. However, the actual substrate removal efficiency must have been greater than 75%, since a fraction of substrate was also utilized in microbial cell synthesis, and these cells were part of the measured total CODcr.
为了最大限度地提高短链脂肪酸甲烷发酵的效率，将以乙酸和丁酸作为主要碳源的生长培养基供应给一个嗜热下行厌氧填充床反应器。该反应器的有机负荷率（OLR）范围为0.2至169千克重铬酸盐化学需氧量（CODcr）/立方米反应器/天，对应的水力停留时间（HRT）为1.4小时至20天。在短至2小时的水力停留时间（OLR = 120千克CODcr/立方米/天）下，维持了稳定的甲烷产生，进料中的短链脂肪酸在此过程中几乎被完全去除。根据进水和出水的总CODcr值确定的表观底物去除效率，在短水力停留时间下为75%。然而，实际的底物去除效率肯定大于75%，因为一部分底物也用于微生物细胞合成，而这些细胞是所测量的总CODcr的一部分。
