摘要
河流渗滤是一种自然净化过程,污染河水通过该过程在河流沉积层中发生物理、化学和生物作用,使得污染物浓度降低,入渗河水水质得到净化。为了研究BTEX污染河水通过河流渗滤系统时的吸附行为,进行了静态吸附模拟实验。结果表明BTEX4种组分在3种河流沉积物样品中的吸附平衡均可以在48h内完成。通过比较BTEX在3种不同河流沉积物样品中的吸附动力学曲线,可以发现BTEX在粉土中吸附速率最大,细砂中次之,粗砂中最小。BTEX在粉土和细砂中的吸附等温线符合Henry等温吸附方程,而在粗砂中符合Langmuir等温吸附方程。3种土壤中粉土和细砂具有较大的吸附容量,而粗砂吸附容量相对较小;粉土和细砂对苯的吸附能力最强,甲苯次之,乙苯和间二甲苯相对较小。从阻滞因子的计算结果来看,黄河花园口区采集的河流沉积物样品对BTEX各组分的迁移均具有较强的阻滞作用,在较高浓度范围内,河流渗滤系统能够通过吸附作用有效阻滞BTEX污染物,降低其对地下水的危害。
River filtration system is a natural purification, which means while the river water passing through the soil and the aquifer material, potential contaminants in the river water are filtered and removed by a series of physical, chemical and biological actions. Based on static ad- sorption experiments, adsorption kinetic curve and adsorption isotherm of each component of BTEX in three different soil samples were plot- ted, and some conclusions were obtained as follow. （ 1 ）The results of experiments of adsorption dynamics showed that the adsorption reaction balance could be achieved within 48 hours. （2）Adsorption processes in the silt soil and the fine sand were corresponding with Henry model, namely the adsorption capacity was directly proportional to equilibrium concentration of the solution. While adsorption process in the coarse sand accorded with Langmuir model. （ 3 ）By comparison of the adsorption isotherm and the soil-water partition coefficient Kd of each BTEX component in different soil samples, it was found that the sih soil and the fine sand possessed relatively higher adsorption capacity than that of the coarse sand. The results also showed that the silt soil and fine sand samples displayed the strongest adsorption capacity to Benzene, to Toluene the second, and that to Ethyl-benzene and M-xylene were much weaker.（4）The retarding factors were relatively high, which showed that the samples of river sediments exhibited quite significant retarding action to BTEX components. BTEX could be removed rather efficient- ly through adsorption action within a quite high concentration range in the river filtration system.
出处
《农业环境科学学报》
CAS
CSCD
北大核心
2012年第6期1203-1208,共6页
Journal of Agro-Environment Science
基金
国家自然基金项目(40772165)
华北水利水电学院高层次人才科研启动金项目
