盐度对序批式生物膜反应器性能及微生物活性的影响

Effects of Salinity on Performance and Microbial Activity of Sequencing Biofilm Batch Reactor

本文研究了盐度变化对序批式生物膜反应器(SBBR)性能及微生物活性的影响。研究结果表明,进水盐度不超过1.5%时,SBBR对COD的平均去除率高于88.63%,但进水盐度为2.5%时,对SBBR的COD去除产生抑制。当进水盐度由0%增加到2.5%时,NH^+_4—N去除未受到影响,出水NO^-_3—N浓度在0.30～3.30 mg/L范围内变化,然而出水NO^-_2—N浓度从0 mg/L逐渐增大到(4.35±0.02) mg/L。比耗氧速率由进水盐度为0%时的(27.39±1.16) mg O_2/(g MLSS·h)增大至进水盐度为1.5%时的(83.41±1.17) mg O_2/(g MLSS·h),而在盐度为2.5%时比耗氧速率降低至(38.62±1.08) mg O_2/(g MLSS·h)。比氨氧化速率、比亚硝酸盐氧化速率、比硝酸盐还原速率和比亚硝酸盐还原速率均随着进水盐度从0%增加到2.5%而逐渐降低。当进水盐度为2.5%时,氨单加氧酶、亚硝酸盐氧化还原酶、硝酸盐还原酶、亚硝酸盐还原酶和脱氢酶的活性与盐度为0%时相比分别降低了41.48%、95.86%、28.57%、27.85%和48.13%,表明盐度增加抑制了微生物酶的活性。

The effects of salinity on the performance and microbial activity of a sequencing biofilm batch reactor(SBBR) were investigated in this study. When the salinity was not more than 1.5%, the average COD removal efficiencies of SBBR were over 88.63%, whereas the COD removal was inhibited at 2.5% salinity. The NH+4-N removal efficiency had no obvious change with the increase of influent salinity from 0% to 2.5%. The effluent NO-3-N concentration varied in the range of 0.30 and 3.30 mg/L during the whole operational process, whereas the effluent NO-2-N concentration gradually increased from 0 to(4.35±0.02) mg/L. The specific oxygen utilization rate gradually increased from( 27.39±1.16) mg O2/(g MLSS·h) to( 83.41±1.17) mg O2/(g MLSS·h) with the increase of influent salinity from 0% to 1.5% and then decreased to(38.62±1.08) mg O2/(g MLSS·h) at 2.5% salinity. The specific ammonia oxidation rate, specific nitrite oxidation rate, specific nitrate reduction rate and specific nitrite reduction rate decreased with the increase of influent salinity from 0% to 2.5%. The ammonia monooxygenase, nitrite oxidoreductase, nitrate reductase, nitrite reductase and docosahexaenoic acid decreased by 41.48%, 95.86%, 28.57%, 27.85% and 48.13% at 2.5% salinity by comparison with 0% salinity, respectively, suggesting that the microbial enzymatic activity were inhibited by the increase of influent salinity.