DO和HRT对MBR同步硝化反硝化影响研究

Influence of DO and HRT on simultaneous nitrification and denitrification in MBR

通过连续运行MBR研究了DO和HRT对同步硝化反硝化的影响,同时对好氧反应器中实现SND的机理进行了探讨.试验结果表明：COD在250 mg/L左右,C/N为10∶1,MLSS为3500 mg/L,HRT为8.5h的相对稳定条件下,当DO为0.6~0.8 mg/L时,总氮去除率达66.7%,取得了最好的TN去除效果,DO过高或过低都会影响同步硝化反硝化的进行;控制DO在1.0 mg/L左右,其他操作条件相同,HRT为5 h,TN去除率达到最高为60%以上,随HRT的延长,同步硝化反硝化效果反而下降;研究结果还表明由于好氧反应器中缺氧区的存在,控制操作条件可以实现SND,同时也存在着短程SND的现象,实现SND可能是几种作用机制的共同结果.

The effects of HRT and DO on the Simultaneous Nitrification and Denitrification （SND） in MBR and the SND mechanism in aerobic reactor were studied. The results indicated that at the COD = 250 mg/L, C/N = 10： 1, MLSS =3500 mg/L, HRT =8. 5 h, while DO was controlled at 0. 6 -0. 8 mg/L, the removal ratio of TN reached the climax about 66. 7%. When other conditions were controlled the same as before, the removal efficiency reached to 60% at HRT = 5 h and then began to declined along with the HRT extending. The results also suggested that since anaerobic area existed, through controlling the operating condition, the SND could be fulfilled. At the same time, the short - cut SND phenomena also exited. All of this showed that the SND was carried out by combined action of some kinds of mechanism.