Pereira M A, Cavaleiro A J, Mota M, Alves M M
Centro de Engenharia Biológica, Universidade do Minho, 4710-057 Braga Portugal.
Water Sci Technol. 2003;48(6):33-40.
Accumulation of substrate onto the biomass was quantified under steady-state and shock conditions in a fixed bed reactor fed with an oleic acid-based synthetic effluent. The accumulation of substrate onto the sludge was more dependent on oleic acid concentration than on oleic acid loading rate and decreased the acetogenic, acetoclastic and hydrogenophilic activity. However, even when the methanogenic activity measurements indicate a severe inhibition, the anaerobic sludge was able to methanise efficiently the accumulated substrate that was mainly adsorbed LCFA. Methanogenic activity measurements for a sludge loaded with 2,861 mg COD/gVSS as LCFA, revealed that only hydrogenophilic activity was detected, whereas the methanogenic activities with acetate, propionate and butyrate as substrates were null. However the methanogenic activity of the same sludge after allowing the depletion of the adsorbed LCFA were significantly enhanced in the presence of all substrates, except in propionate. A discussion about the relative importance of metabolic inhibition and transport limitations for the anaerobic degradation of LCFA is launched.
在一个以油酸基合成废水为进料的固定床反应器中，在稳态和冲击条件下对生物质上底物的积累进行了量化。底物在污泥上的积累更多地取决于油酸浓度，而非油酸负荷率，并且降低了产乙酸、乙酸裂解和嗜氢活性。然而，即使产甲烷活性测量表明存在严重抑制，厌氧污泥仍能够有效地将主要吸附的长链脂肪酸（LCFA）形式的积累底物甲烷化。对负载有2861 mg COD/gVSS的LCFA污泥的产甲烷活性测量表明，仅检测到嗜氢活性，而以乙酸盐、丙酸盐和丁酸盐为底物的产甲烷活性为零。然而，在吸附的LCFA耗尽后，相同污泥在所有底物存在下（丙酸盐除外）的产甲烷活性显著增强。本文展开了关于代谢抑制和传输限制对LCFA厌氧降解的相对重要性的讨论。
