Investigation of the treatment efficiency and mechanism of microporous flocculation magnetic fluidized bed (MFMFB) reactor for Pb(II)-containing wastewater

Abstract

In this study, a novel microporous flocculation magnetic fluidized bed (MFMFB) reactor was proposed for the treatment of low concentration lead-polluted groundwater in Gansu Province, China. It introduced a magnetic levitation layer and non-coincident counterflow inlet by using flocculants of polyaluminum chloride (PAC) and polyacrylamide (PAM). And Particle Image Velocimetry (PIV) was used in conjunction with flocculation experiments. The results showed that when the dosage of poly PAC and PAM was 120 mg/L and 1 mg/L, respectively, at the same time the water inflow was 0.013–0.020 m3/h, the removal efficiency of Pb(II) and turbidity reached a steady level of over 98% in low turbidity and concentration Pb(II)-containing simulated wastewater. The reactor created favorable conditions for enhanced flocculation in terms of water flow direction, velocity gradient, effective energy consumption and microporous flocculation. Microporous flocculation form on the surface of the magnetic levitation layer, where fine particles contributed to both mixing and adsorption. The reactor possessed comprehensive flocculation effects such as anisotropy, micro-vortex, and microporous, and has the potential to treat low Pb(II)-containing groundwater.