Testing Soil Accumulation of Cd from Reclaimed Water

Abstract

The reuse of wastewater improves the comprehensive utilization of water resources, and reduces the shortage of water resources. In this paper, the accumulation of heavy metal Cd risk in reclaimed water irrigated soil to human health was analysised through experiments and simulations. Firstly, according to the static adsorption experiment of sandy clay loam, the fitting effect of Freundlich equation on Cd is better for the certainty coefficient R2 reaches 0.97. Then, use the more accurate DEM model of CXTFIT2.1 software to fit the Cl- penetration curve. Finally, made the heavy metal leading experiment, found that the TSM model has a good fitting effect on the penetration curve of Cd, with a determination coefficient close to 1 and a small standard error coefficient. Based on the results of the above experiments, the HYDRUS-1D was used to analyze and predict the cumulative risk of Cd in reclaimed water irrigated soil. The results showed that: after 100 years under current situations, the predicted concentration of Cd in soil may reach 0.742 mg/kg, which exceeded the national soil environmental quality standard, may be a serious health hazard. Measures should be taken to reduce the risk of human health by ingestion and accumulation of crops and vegetables.