缺氧折流板反应器的流态及污泥颗粒运动分析

Flow pattern and sludge movement in the anoxic baffled reactor

采用缺氧折流板反应器(ABR)处理印染废水,当HRT为8h时,ABR内的下向导流室雷诺数(Re)为1.1,上向流反应室Re为0.1,均为层流。污泥颗粒经绕流运动分析,下向导流室污泥颗粒受到的绕流阻力和重力均向下,只有浮力向上,由于污泥颗粒密度大于流体的密度,此时重力大于浮力,污泥颗粒不能在下向导流室内稳定停留,即没有污泥层,与观察到的试验现象一致。在上向流反应室的污泥颗粒受到的绕流阻力向上,重力与绕流阻力、浮力处于动态平衡时的污泥颗粒的临界粒径(dcr)为85μm。

A lab size anoxic baffled reactor （ABR） was employed for treatment of the textile dyeing wastewater. Operating at a hydraulic retention time of 8 h, Reynolds numbers of the diversion and biochemical reaction sections were 1.1 and 0.1, respectively, indicating the flow there were laminar. The directions of resistance and gravity were downward, while the direction of buoyancy was upward. Since the sludge particles were heavier than water, the grav- ity was larger than buoyancy. As expected, the sludge particles were unable to stay in the diversion section to form a sludge blanket. The direction of resistance was upward in the biochemical reaction section. When gravity, resistance and buoyancy were in dynamic equilibrium, the critical particle diameter was 85μm; therefore, sludge particles larger than this size were retained in the biochemical reaction section.