The effect of nickel deprivation from the influent of a mesophilic (30 degrees C) methanol fed upflow anaerobic sludge bed (UASB) reactor was investigated by coupling the reactor performance to the evolution of the Methanosarcina population of the bioreactor sludge. The reactor was operated at pH 7.0 and an organic loading rate (OLR) of 5-15 g COD l(-1) day(-1) for 191 days. A clear limitation of the specific methanogenic activity (SMA) on methanol due to the absence of nickel was observed after 129 days of bioreactor operation: the SMA of the sludge in medium with the complete trace metal solution except nickel amounted to 1.164 (+/-0.167) g CH(4)-COD g VSS(-1) day(-1) compared to 2.027 (+/-0.111) g CH(4)-COD g VSS(-1) day(-1) in a medium with the complete (including nickel) trace metal solution. The methanol removal efficiency during these 129 days was 99%, no volatile fatty acid (VFA) accumulation was observed and the size of the Methanosarcina population increased compared to the seed sludge. Continuation of the UASB reactor operation with the nickel limited sludge lead to incomplete methanol removal, and thus methanol accumulation in the reactor effluent from day 142 onwards. This methanol accumulation subsequently induced an increase of the acetogenic activity in the UASB reactor on day 160. On day 165, 77% of the methanol fed to the system was converted to acetate and the Methanosarcina population size had substantially decreased. Inclusion of 0.5 muM Ni (dosed as NiCl(2)) to the influent from day 165 onwards lead to the recovery of the methanol removal efficiency to 99% without VFA accumulation within 2 days of bioreactor operation.

中文翻译：

---

镍在厌氧颗粒污泥生物反应器中高速率甲醇降解中的作用。

通过将反应器性能与生物反应器污泥 Methanosarcina 种群的进化相结合，研究了从嗜温（30 摄氏度）甲醇进料上流厌氧污泥床 (UASB) 反应器中去除镍的影响。反应器在pH 7.0和5-15g COD 1(-1)天(-1)的有机负载率(OLR)下运行191天。在生物反应器运行 129 天后，观察到由于不含镍，甲醇的特定产甲烷活性 (SMA) 受到明显限制：除镍外，含有完全痕量金属溶液的培养基中污泥的 SMA 达 1.164 (+/- 0.167) g CH(4)-COD g VSS(-1) 天 (-1) 与 2.027 (+/-0.111) g CH(4)-COD g VSS(-1) 天 (-1) 相比，在培养基中用完整的（包括镍）痕量金属溶液。这 129 天的甲醇去除效率为 99%，未观察到挥发性脂肪酸 (VFA) 积累，与种子污泥相比，甲烷八叠球菌种群的规模有所增加。继续使用镍限制污泥的 UASB 反应器操作导致甲醇去除不完全，因此从第 142 天起甲醇在反应器流出物中积累。这种甲醇积累随后在第 160 天诱导了 UASB 反应器中产乙酸活性的增加。在第 165 天，供给系统的甲醇的 77% 转化为乙酸盐，并且甲烷八叠球菌种群数量显着减少。从第 165 天起将 0.5 μM Ni（以 NiCl(2) 形式给药）加入进水可在生物反应器运行的 2 天内将甲醇去除效率恢复到 99%，而不会产生 VFA。