Abstract Scarce attention has been placed on the geometry of anoxic fluidized bed membrane bioreactors (AFMBR) affecting the hydrodynamic pattern inside the reactor and, consequently, on the mechanical cleaning driven by granular carbon (GC) around the membrane. The present work evaluated the application of a swirling fluidization, produced by a tangential inlet in a reactor with hydrocyclone geometry, with the aim to avoid membrane fouling during the performance of a denitrification process. The study includes 3D-hydrodynamic description of the flow and particles fluidization through computation fluid dynamics (CFD), experimentally validated with the particle image velocimetry (PIV) technique. Water shear stress and GC particles momentum acting over the membranes were also assessed, in addition to monitoring filtration and denitrification performance. The conical section showed higher shear stress and particles momentum as compared to the cylindrical zone. Soluble microbial products (SMP) accumulated on the membrane walls with lower shear stress and particles momentum. The operation of the AFMBR was maintained with a continuous permeate flow without any change in suction pressure and the nitrate removal efficiency was above 90% with negligible accumulation of NO2− and N2O in the denitrifying process. This novel reactor configuration could be suitable for the treatment of industrial wastewaters.

中文翻译：

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缺氧膜生物反应器中的旋流流化作为一种​​防污技术

摘要 缺氧流化床膜生物反应器 (AFMBR) 的几何形状会影响反应器内的流体动力学模式，因此受到膜周围颗粒碳 (GC) 驱动的机械清洗的影响很少受到关注。目前的工作评估了旋流流化的应用，该流化是由具有水力旋流几何形状的反应器中的切向入口产生的，目的是在反硝化过程中避免膜污染。该研究包括通过计算流体动力学 (CFD) 对流动和粒子流化的 3D 流体动力学描述，并通过粒子图像测速 (PIV) 技术进行了实验验证。还评估了作用在膜上的水剪切应力和 GC 颗粒动量，除了监测过滤和反硝化性能。与圆柱形区域相比，锥形截面显示出更高的剪切应力和颗粒动量。可溶性微生物产物 (SMP) 在具有较低剪切应力和颗粒动量的膜壁上积累。AFMBR 的运行保持连续的渗透流，吸入压力没有任何变化，硝酸盐去除效率在 90% 以上，在反硝化过程中 NO2- 和 N2O 的积累可以忽略不计。这种新型反应器配置可适用于处理工业废水。AFMBR 的运行保持连续的渗透流，吸入压力没有任何变化，硝酸盐去除效率在 90% 以上，在反硝化过程中 NO2- 和 N2O 的积累可以忽略不计。这种新型反应器配置可适用于处理工业废水。AFMBR 的运行保持连续的渗透流，吸入压力没有任何变化，硝酸盐去除效率在 90% 以上，在反硝化过程中 NO2- 和 N2O 的积累可以忽略不计。这种新型反应器配置可适用于处理工业废水。