VERTICAL FLOW ARTIFICIAL WETLAND SYSTEM OF WASTE BRICKS REMOVES PHOSPHORUS IN RURAL DOMESTIC WASTEWATER AND PHOSPHORUS TRANSPORT CHARACTERISTICS

摘要

Phosphorus is an important element that causes water pollution. Artificial wetlands can efficiently dispose phosphorus in domestic sewage. The removal efficiency of phosphorus in domestic sewage and migration characteristics of phosphorus in the system were studied using waste brick artificial wetland. Results were compared between artificial wetland constructed using rural waste red clay brick and a conventional gravel artificial wetland system. Results show that the adsorption intensity of phosphorus by waste bricks was stronger than that of conventional gravel. The removal of phosphorus from waste brick artificial wetland and gravel artificial wetland mainly depended on the adsorption and sedimentation of the filler matrix. The contribution to phosphorus removal by waste brick artificial wetland and gravel artificial wetland was 90.36% and 87.36%, respectively. The adsorption of phosphorus by the filler decreased with rising depth, and the adsorption of phosphorus mainly occurred at 0-40 cm. Plant absorption played a minor role, and the contribution rates of phosphorus removal by waste brick artificial wetland and gravel artificial wetland were 9.64% and 12.5%, respectively. The accumulation of phosphorus in the two systems was mainly concentrated on the ground, and the accumulation of total phosphorus was more than 80% of the total amount. The order of total phosphorus in different plant parts was leaf> stem〉root. Waste brick artificial system of sewage phosphorus reached the discharge standards of municipal sewage treatment plant pollutant (GB18918-2002) level A standard). Rural waste clay red brick should be selected as a new filler to build an artificial wetland system that deals with rural sewage.