化学淋洗法修复盐渍化Pb污染土壤OA

This study focuses on the farmland soil of Zhenhe Village,a typical agricultural irrigation area in Ningxia.Using a combination of batch experiments and soil column experiments,it investigates the effects of the type,concentration,dosage,and leaching duration of leaching agents on the removal rate of Pb in simulated Pb-contaminated soil.Soil column simulation experiments were conducted to study the remediation of Pb-contaminated soils with different Pb contents and salinization levels using the leaching method.The results show that disodium ethylenediaminetetraacetate(EDTA-2Na)solution achieves the highest Pb removal rate in saline soils.For 1 g of soil,under the conditions of 10 mL of EDTA-2Na solution with a concentration of 0.4 mol/L leached for 6 hours,the Pb removal rate in the soil is maximized.The removal rate of Pb using EDTA-2Na solution is significantly higher in high-Pb saline soils(67.9%)compared to soils with low Pb content.After EDTA-2Na leaching,the total salt content in low-salinity soils increases compared to the initial soil,whereas in high-salinity soils,the total salt content decreases.Although increasing the number of leaching treat-ments improves the Pb removal rate in soil(84.9%),it also increases soil salinization.Under optimal condi-tions,leaching saline Pb-contaminated soil with EDTA-2Na solution can effectively remove Pb from the soil;however,the impact on soil salinization must be taken into account.