膨胀颗粒污泥的恢复及其基质降解动力学

Remediation of filamentous bulking granule and its substrate degradation kinetics

为实现丝状菌膨胀的好氧颗粒污泥(AGS)的修复,通过在序批式活性污泥(sequencing batch reactor activated sludge process,SBR)反应器中设置厌氧生物选择段以抑制丝状菌生长,并研究了修复过程中污泥基质降解动力学参数变化。膨胀AGS表面包裹了大量丝状菌(污泥体积指数SVI高达186.56m L/g),但恢复过程中膨胀AGS的比例逐渐减少,表面逐渐变得清晰、规则,21d时污泥膨胀趋势已完全得到遏止,最终AGS的污泥沉降比SV_(30)/SV_5、SVI和颗粒化率分别为0.92、48.74m L/g及92.79%,并表现出良好的污染物去除效果。通过双倒数法拟合得到丝状菌膨胀AGS的饱和常数和最大比增长速率分别为75.67mg/L、0.47h^(-1),该值略高于普通活性污泥,但远低于恢复稳定后AGS的354.47mg/L、1.43h^(–1)。因此,在厌氧生物选择段创造的高底物浓度环境下,AGS中菌胶团细胞可优先获得基质并实现增殖,而丝状菌由于生长受到抑制而逐渐被淘汰,最终在22d内实现膨胀AGS的修复。

In order to realize the remediation of filamentous bulking aerobic granular sludge（AGS）,an anaerobic biological selector was employed in a SBR to inhibit filamentous bacteria growth.Variations of sludge substrate degradation kinetic parameters during the remediation process were investigated.A large amount of filamentous bacteria were entrapped on the surface of the bulking AGS（SVI was up to186.56m L/g）.However,the proportion of bulking AGS gradually decreased and its surface gradually became smooth and clear,and the trend of sludge bulking was completely inhibited on the 21st day.SV_（30）/SV_5,SVI and granulation rate of the AGS eventually reached to 0.92,48.74m L/g and 92.79%respectively,and good pollutants removal performances were achieved.The maximum specific growth rate and saturated constant of filamentous bulking AGS were obtained by double reciprocal method,which were 75.67mg/L and 0.47h^（–1）,respectively.Although the two parameters were slightly higher than that of activated sludge,they were much lower than that of AGS recovered,which were 354.47mg/L and 1.43h^（–1）.Therefore,the zoogloea bacteria insides AGS was prior to obtain substrate and proliferate under high substrate concentration environment created by the anaerobic biological selector,while the filamentous fungi gradually eliminated due to the growth inhibition,and remediation of bulking AGS was finally realized within 22 days.