苯·萘·菲在地下水含水层介质中的迁移规律研究

[目的]采用模拟渗流槽装置研究地下水中苯、萘、菲3种物质在含水层介质中的迁移规律。[方法]根据污染场地水文地质特征及污染特征,用地下水配制的苯、萘、菲3种污染物混合溶液作为试验供水水源,采取侧向补给的方式进行地下水在渗流槽的迁移试验。[结果]苯、萘、菲3种物质在含水层介质中的迁移速率大小顺序为苯萘菲;同时,4种含水层介质对污染组分的阻滞能力大小顺序为粉砂中砂粗砂砾砂;污染物在含水层中的迁移过程主要受吸附作用和微生物降解作用影响。各含水层介质对苯、萘、菲均有一定的吸附作用;在微生物降解苯、萘、菲的过程中,反应体系由好氧条件逐渐过渡为缺氧或者厌氧条件,电子受体由原来的O2变成了NO3-N和Fe(Ⅲ)。[结论]污染物在地下水中的迁移过程包括吸附作用和微生物降解作用。

Research on Migration of Benzene, Naphthalene, Phenanthrene in Aquifer Medium

[Objective]The aim was to study the migration of benzene,naphthalene,phenanthrene in the aquifer medium by using a simulated device of permeability flume.[Method]According to the hydrogeological characteristics of contaminated sites and pollution characteristics,the preparation of solution was mixed with three pollutants—benzene,naphthalene,phenanthrene—in the groundwater,which as water resources supply to the device of permeability flume,and the flow in experimental tank was adopted the lateral supply mode to the migration of groundwater.The tank was filled with four different size of aquifer medium: silty sand,medium sand,coarse sand and gravel sand.[Result] The results showed that the sequence of the migration velocities of benzene,naphthalene,phenanthrene in the aquifer medium is benzene > naphthalene > phenanthrene;and that of the retardation abilities of the four different aquifer medium is silty sand > medium sand > coarse sand > gravel sand.The migration process of the three pollutants in the aquifer medium is mainly affected by two factors: adsorption and microbial degradation.Benzene,naphthalene,phenanthrene are more or less adsorbed by all four aquifer medium.Because of the process of the microbial degradation,the reaction condition in the aquifer medium is gradually changed from aerobic condition to anoxic condition or anaerobic condition,meanwhile,the electron acceptor is changed from O2 to NO3-N and Fe(Ⅲ).[Conclusion]The migration process of pollutants in groundwater includes adsorption and microorganism.