二次流场促进颗粒污泥成型的研究

RESEARCH OF SECONDARY FLOW PROMOTING SLUDGE GRANULATION IN SSRB

对提供特定流体动力条件(二次流)的SSBR反应器和普通SBR反应器对比,同步培养高浓度好氧颗粒污泥,研究二次流场对好氧颗粒污泥成型的影响及其机理。试验发现:在SSBR反应器中,利用可控二次流场培养好氧颗粒污泥,其启动时间有较大程度地缩短,仅4d就出现白色绒球状颗粒污泥,相比普通SBR反应器更快。SSBR运行稳定时,MLSS最高可达到15.2g/L,其颗粒污泥平均粒径为(1.43±0.2)mm,最大可达5mm左右,污泥体积指数(SVI)低于40mL/g,其污泥结构的紧凑性可通过流体动力条件调整。通过分析认为污泥颗粒化是絮体污泥间有效碰撞的结果。控制流体动力条件形成均匀剪切力且高效循环的流场,使有效碰撞几率增大,加快了污泥颗粒化进程,使颗粒污泥的性能也发生了改变。

This study investigated the effect of optimized secondary flow on formation of aerobic granules through cultivating aerobic granules.For this purpose,two sequencing batch reactors were operated at different flow field:secondary flow and up flow.Results showed that aerobic granules formed in two reactors.The startup time in SSBR is faster than that in SBR and the white floccules were appeared after settling time is greatly shortened to 4 days to make.During the two months operation,the MLSS can reach 15.2 g/L as the highest point under the stable operation of SSBR,the size of sludge granules is 1.43±0.2mm in average(up to 5 mm)and the sludge volume index(SVI)is less than 40ml/g under the steady condition of SSBR,then the compact of sludge's structure can be modulated by conditions of hydraulic.This study demonstrated that hydrodynamic shear force as through secondary flow would be useful strategy for improving the stability of aerobic granules and accelerate the process for granulation.It is an available method of realizing higher concentrated aerobic granules.