微气泡曝气对生物膜反应器启动运行性能影响

比较了微气泡曝气(MB)与传统气泡曝气(CB)流化床生物膜反应器启动运行性能,以及生物膜形成过程与组成特性.结果表明,启动运行中,MB反应器的COD、NH4+-N和TN平均去除率分别达到90.3%、92.7%和43.4%,而CB反应器的COD、NH4+-N和TN平均去除率分别为79.4%、86.3%和29.3%,MB反应器污染物去除性能优于CB反应器.同时,MB反应器的氧利用率高达94.3%,显著高于CB反应器.MB反应器中生物膜形成速率和稳定生物膜生物量均高于CB反应器,并且所形成的生物膜VSS/SS比值较高而EPS含量较低.因此,微气泡曝气能够加速生物膜形成并获得更高的活性生物量,从而提高生物膜反应器的启动运行性能.

Influence of microbubble aeration on start-up and performance of a biofilm reactor.

Two fluidized biofilm reactors with microbubble aeration (MB) and conventional bubble aeration (CB) were operated simultaneously to compare their performances during start-up and stable operation. The biofilm formation and composition in both reactors were also investigated. The results showed the average removal efficiencies of COD, NH4+-N and TN were 90.3%, 92.7% and 43.4% in MB reactor during start-up and stable operation, respectively. The corresponding removal efficiencies in CB reactor were 79.4%, 86.3% and 29.3%, respectively. MB reactor presented more efficient performance of contaminant removal than CB reactor. In addition, the oxygen utilization efficiency in MB reactor reached 94.3%, which was much higher than that in CB reactor. Faster biofilm formation and larger biofilm biomass were achieved in MB reactor, compared with CB reactor. Moreover, the biofilm formed in MB reactor showed higher VSS/SS ratio and lower EPS content. These results demonstrated that biofilm formation was enhanced by microbubble aeration in MB reactor, which contained more active biomass.