Experimental and Numerical Simulation on Hexavalent Chromium Migration Characteristics by Permeable Fine-Grained Sand Barrier Filters

Abstract

The presence of toxic hexavalent chromium poses a great challenge in the wastewater pretreatment of agricultural irrigation. The feasibility of using fine-grained sands as suitable filling materials in the permeable barrier filter was studied for the effective containment of hexavalent chromium. Based on the governing equations representing seepage-field coupled concentration-field, a physical model composed of the fine-grained sands ranging from 0.075–0.5 mm was tentatively designed to remove hexavalent chromium in the permeable barrier filters. The column physical model experiments of 0.5, 0.2, 0.1, and 0.075-mm sands were separately performed under low velocity of