摘要
污染场地土壤-地下水系统中污染组分源强的精准识别是实现地下水污染高效治理与有效防控的根本前提.针对某固废填埋场地1号、3号地块地下水As(Ⅲ)浓度出现高值异常,采用统计相关分析方法分析了地下水中As(Ⅲ)与其他检出特征组分的相关关系,确定了As(Ⅲ)与PO_(4)^(3-)之间的竞争吸附反应是地下水中As(Ⅲ)污染的主要原因;随后采用表面络合模型(SCM)模拟竞争吸附反应,并建立了基于TOUGHREACT的场地土壤-地下水系统As(Ⅲ)污染组分反应运移模型;最后利用粒子群优化(PSO)算法构建了污染地块As(Ⅲ)污染的源强识别的模拟优化模型.结果显示:(1)固废中存在的磷酸盐能解释污染地块土壤不同深度As(Ⅲ)含量较背景值偏高的现象;(2)构建的土壤-地下水系统As(Ⅲ)运移模型可较好地模拟As(Ⅲ)与PO_(4)^(3-)竞争吸附反应;(3)优化识别出1号和3号地块的As(Ⅲ)污染源强分别为187.25μg·L^(-1)和192.49μg·L^(-1).研究表明,基于PSO算法的模拟优化模型具有识别精度高、计算速度快、稳定性好的特点,可用于解决此类土壤-地下水系统污染源强识别问题.
Accurate identification of pollution component source strength in soil-groundwater system of contaminated site is the fundamental premise for effective control and prevention of groundwater pollution.In view of the abnormal concentration of As(Ⅲ)in groundwater of land block 1 and 3 in a solid waste landfill site,the correlation analysis method was used to analyze the correlation between As(Ⅲ)and other characteristic component in groundwater,and the competitive adsorption reaction between As(Ⅲ)and PO_(4)^(3-)was determined to be the main cause of As(Ⅲ)pollution in groundwater.Then a surface complexation model(SCM)was used to simulate the competitive adsorption reaction,and the As(III)reactive transport model of soil-groundwater system based on TOUGHREACT was established.Finally,the particle swarm optimization(PSO)algorithm was used to construct a simulation and optimization model for identifying the source intensity of As(Ⅲ)pollution.The results show that:①The existence of phosphate in the solid waste can explain the phenomenon that the As(Ⅲ)content at different depths of the contaminated soil is higher than the background value.②The As(Ⅲ)transport model in the soil-groundwater system can well simulate the competitive adsorption of As(Ⅲ)and PO_(4)^(3-).③The intensity of As(Ⅲ)pollution sources in block 1 and 3 were identified as 187.25μg·L^(-1) and 192.49μg·L^(-1).The research shows that the simulation optimization model based on PSO algorithm is of high identification accuracy,fast calculation speed and good stability,which can be used to solve the problem on the intensity identification of pollution sources in soil-groundwater systems.
作者
储建民
邱文杰
吴剑锋
吴吉春
CHU Jianmin;QIU Wenjie;WU Jianfeng;WU Jichun(Key Laboratory of Surficial Geochemistry,Ministry of Education,School of Earth Sciences and Engineering,Nanjing University,Nanjing 210023)
出处
《环境科学学报》
CAS
CSCD
北大核心
2024年第2期237-247,共11页
Acta Scientiae Circumstantiae
基金
国家重点研发计划(No.2022YFC3702200)
国家自然科学基金(No.41772254)。
关键词
As(Ⅲ)污染
污染源识别
竞争吸附
粒子群优化算法
As(Ⅲ)pollution
pollution source identification
competitive adsorption
particle swarm optimization algorithm
