进水NH_(4)^(+)-N对多毛型片状组合填料SBBR脱氮性能和胞外聚合物的影响

Effects of Influent NH_(4)^(+)-N on Nitrogen Removal Performance and Extracellular Polymeric Substances of Hairy Flake Composite Packing SBBR

研究了进水NH_(4)^(+)-N对多毛型组合填料序批式生物膜反应器(SBBR)脱氮性能、脱氮速率和胞外聚合物(EPS)的影响。结果表明:当进水NH_(4)^(+)-N浓度由30 mg/L增加到50 mg/L时,化学需氧量(COD)和NH_(4)^(+)-N的去除率保持稳定,分别为91.24%±1.01%和98.66%±1.32%,出水NO_(3)^(-)-N浓度由(2.68±0.35)mg/L上升至(6.66±0.16)mg/L;与NH_(4)^(+)-N浓度为30 mg/L相比,当进水NH_(4)^(+)-N浓度为50 mg/L时,比氨氧化速率、比亚硝酸盐氧化速率、比亚硝酸盐还原速率和比硝酸盐还原速率分别降低了8.24%、11.25%、10.62%和10.74%,脱氢酶、氨单加氧酶、亚硝酸盐氧化还原酶、亚硝酸盐还原酶和硝酸盐还原酶的活性分别下降了11.23%、10.28%、13.54%、13.83%和12.91%。这说明高浓度NH_(4)^(+)-N条件下,低碳氮比导致生物膜脱氮性能下降,增加NH_(4)^(+)-N浓度能抑制酶活性,提升EPS、疏松型EPS(LB-EPS)和紧密型EPS(TB-EPS)的产量,提高LB-EPS、TB-EPS中蛋白质和多糖的含量。

The effects of the influent NH_(4)^(+)-N concentration on the nitrogen removal performance,nitrogen removal rate and extracellular polymeric substances(EPS)of the hairy flake composite packing sequencing biofilm batch reactor(SBBR)was investigated.The results showed that when the influent NH_(4)^(+)-N concentration was increased from 30 mg/L to 50 mg/L,the removal efficiencies of chemical oxygen demand(COD)and NH_(4)^(+)-N remained stable,which were 91.24%±1.01%and 98.66%±1.32%,respectively.And the effluent NO_(3)^(-)-N concentration increased from(2.68±0.35)mg/L to(6.66±0.16)mg/L.Compared with the influent NH_(4)^(+)-N concentration at 30 mg/L,when the influent NH_(4)^(+)-N concentration at 50 mg/L,the specific ammonia oxidation rate,the specific nitrate oxidation rate,the specific nitrate reduction rate and the specific nitrate reduction rate decreased by 8.24%,11.25%,10.62%and 10.74%respectively,and the activities of dehydrogenase,ammonia monooxygenase,nitrite oxidoreductase,nitrite reductase and nitrate reductase decreased by 11.23%,10.28%,13.54%,13.83%and 12.91%respectively.This indicates that under high concentration of NH_(4)^(+)-N,the low C/N ratio leads to the decline of nitrogen removal performance of biofilms.The increase of NH_(4)^(+)-N concentration inhibits enzyme activity,improves the production of EPS,loosely bound EPS(LB-EPS)and tightly bound EPS(TB-EPS),and increases the content of protein and polysaccharide in LB-EPS and TB-EPS.