反硝化除磷+短程反硝化厌氧氨氧化工艺的深度脱氮除磷效能

Achieving advanced nitrogen and phosphorus removal based on denitrifying phosphorus removal and partial denitrification Anammox process

为经济高效地去除城市生活污水和硝酸盐废水中的氮磷元素,本研究在厌氧折流板反应器(ABR)和连续搅拌反应器(CSTR)一体式反应器中分别建立了反硝化除磷(DPR)和短程反硝化厌氧氨氧化(PDA)工艺。结果表明,反应器运行185天,在缺氧/厌氧和外加COD/NO_(3)^(-)-N比仅为0.7条件下,PO_(4)^(3-)-P和TN的去除率高达96.91%和97.75%,最终出水PO_(4)^(3-)-P和TN的浓度低至0.22mg/L和3.30mg/L,意味着该系统极佳的脱氮除磷效果不依赖氧气和有机碳源量。DPR对系统PO_(4)^(3-)-P和TN的去除均占主体部分(99.07%和60.23%),而PDA对总氮(TN)的去除占比呈现逐渐上升的趋势(4.53%→37.52%)。批次实验表明:①COD(300mg/L)显著抑制DPR菌活性,PO_(4)^(3-)-P主要是在缺氧状态下以NO_(3)^(-)-N为电子受体,有机物为电子供体通过DPR途径去除;②高效短程反硝化过程(亚硝酸转化率92.25%)稳定为厌氧氨氧化供给电子受体(NO_(2)^(-)-N),DPR系统剩余NH_(4)^(+)-N主要被NO_(2)^(-)-N氧化去除,因此DPR+PDA系统实现了高效同步脱氮除磷效果。高通量测序表明,Accumulibacter(7.41%)是DPR系统功能性除磷菌,Thauera(7.24%)和Candidatus Brocadia(3.12%)为PDA系统关键脱氮菌。

In order to remove nitrogen and phosphorus from municipal wastewater and nitrate wastewater economically and efficiently,denitrifying phosphorus removal(DPR)and partial denitrification Anammox(PDA)processes were established in an Anaerobic Baffled Reactor(ABR)and Continuous Stirred Tank Reactor(CSTR)integrated reactor,respectively.Results showed that the removal efficiencies of PO_(4)^(3-)-P and TN were 96.91%and 97.75%,respectively,under the conditions of anoxic/anaerobic and external COD/NO3--N ratio of 0.7 after 185 days of operation.The final effluent PO_(4)^(3-)-P and TN concentrations were as low as 0.22mg/L and 3.30mg/L,respectively,which indicated that the excellent nitrogen and phosphorus removal efficiency of the system independent of oxygen and organic carbon sources.The removal of PO_(4)^(3-)-P and TN by DPR accounted for 99.07%and 60.23%of the total,respectively,while the proportion of TN removal by PDA increased gradually(4.53%→37.52%).Batch experiments showed that,①high concentration of COD(300mg/L)significantly inhibited the activity of DPR bacteria,and PO_(4)^(3-)-P was mainly removed by DPR with NO-3-N as electron acceptor and organic matter as electron donor under anoxic condition;②the highly-efficient partial denitrification process(NTR 92.25%)supplied stable electron acceptor(NO-2-N)for anammox,andthe residual NH+4-N of DPR system was mainly eliminated by NO-2-N oxidation.Therefore,the DPR+PDA system had achieved the high-efficiency and synchronous nitrogen and phosphorus removal effect.High throughput sequencing showed that Accumulibacter(7.41%)was the functional phosphorus removal bacteria in DPR system,and Thauera(7.24%)and Candidatus Brocadia(3.12%)were the key nitrogen removal bacteria in PDA system.