Demirel B, Yenigün O
Environ Technol. 2002 Oct;23(10):1179-87. doi: 10.1080/09593332308618336.
The effects of changes in composition of a volatile fatty acid mixture (namely acetic, propionic and butyric acids) fed to a methanogenic upflow filter reactor (UFAF) were investigated in terms of reactor chemical oxygen demand (COD) removal efficiency and biogas production level. A mixed substrate consisting of differing proportions of VFAs (on a COD basis) was fed to the reactor in semi-continuous mode under constant organic loading rate (OLR) and hydraulic retention time (HRT). At an OLR of 1.2 kg COD m(-3) x d and HRT of 4 days, increasing propionic acid concentrations of about 312 mg l(-1), 617 mg l(-1), 951 mg l(-1) and 1242 mg l(-1) fed to the reactor provided COD removal rates and biogas production levels of, 84.70%-1301 ml d(-1), 80.80%-1214 ml d(-1), 73.65%-1071 ml d(-1) and 65.53%-942 ml d(-1), respectively, indicating inhibitory effects of propionic acid on the methanogenic ecosystem. Subsequent introduction of butyric acid (247 mg l(-1)) in addition to propionic acid (891 mg l(-1)) increased the performance of the UFAF, yielding 76.10% COD removal and 1075 ml d(-1) of biogas production. The instability observed in the system towards the end of the study probably originated from operating the reactor at relatively high VFA concentrations for a long period of time. Change in VFA composition did not seem to have significant effects on the effluent MLVSS/MLSS ratio. The upflow anaerobic filter reactor adapted to variations in feed composition in a short period of time.
研究了向产甲烷上流式过滤反应器（UFAF）中投喂挥发性脂肪酸混合物（即乙酸、丙酸和丁酸）的组成变化对反应器化学需氧量（COD）去除效率和沼气产量的影响。在恒定有机负荷率（OLR）和水力停留时间（HRT）下，以半连续模式将由不同比例挥发性脂肪酸（基于COD）组成的混合底物投喂到反应器中。在OLR为1.2 kg COD m(-3)×d且HRT为4天的条件下，向反应器中投喂的丙酸浓度分别增加约312 mg l(-1)、617 mg l(-1)、951 mg l(-1)和1242 mg l(-1)时，COD去除率和沼气产量分别为84.70%-1301 ml d(-1)、80.80%-1214 ml d(-1)、73.65%-1071 ml d(-1)和65.53%-942 ml d(-1)，表明丙酸对产甲烷生态系统具有抑制作用。随后，除了丙酸（891 mg l(-1)）之外再引入丁酸（247 mg l(-1)）提高了UFAF的性能，COD去除率达到76.10%，沼气产量为1075 ml d(-1)。在研究接近尾声时系统中观察到的不稳定性可能源于长时间在相对较高的挥发性脂肪酸浓度下运行反应器。挥发性脂肪酸组成的变化似乎对出水的MLVSS/MLSS比值没有显著影响。上流式厌氧过滤反应器在短时间内适应了进料组成的变化。
