摘要
监测自然衰减技术(MNA)作为污染场地有效的风险防控手段在世界范围内得到广泛应用,该技术应用的核心是确定污染物衰减能力及效率。而其衰减能力及效率会受到污染物本身特性,以及场地典型地球化学、水文地质条件等固有特征影响,明确场地固有性质对污染物自然衰减的影响对该技术的合理应用具有更为重要的实际意义。以场地典型地球化学特征与水文地质特征为重点,阐述了两者对地下水中污染物自然衰减过程的影响及其作用机理。沉积物有机质和矿物组成等典型地球化学特征控制污染物的吸附络合行为,同时参与电子传递过程从而影响污染物的生物降解及化学转化过程;水文地质条件方面,含水层岩性及结构特征会导致渗透性、吸附解吸能力有所差异,从而影响污染物的自然衰减能力,地下水流速控制污染物对流弥散作用,同时影响污染物从沉积物固相向地下水的溶解释放以及生物降解动力学过程。总体上,由于有机质、矿物、微生物组分的复杂性,加之水文地质条件的不均质性,场地固有性质对污染物自然衰减的影响研究还有待进一步加强,尤其要通过长期的场地监测,识别污染物衰减的时空动态规律,深化对场地典型地球化学、水文地质条件与污染物相互作用机制的认识。
As an effective risk prevention and control tool for contaminated sites,Monitoring Natural Attenuation(MNA)has been applied worldwide.The core of this technology is to determine the ability and efficiency of pollutant attenuation,which are influenced by the nature of the pollutants themselves,as well as the typical geochemical and hydrogeological conditions and other inherent characteristics of the site.It is of greater practical importance to clarify the influence of the inherent properties of the site on the natural attenuation of pollutants for the rational application of the technology.The authors address the influence of typical site geochemical characteristics and hydrogeological characteristics on the natural attenuation process of pollutants in groundwater and its mechanism.The typical geochemical characteristics,such as the organic matter and mineral composition of sediments,control the adsorption and complexation behavior of pollutants,and participate in the electron transfer process to influence the biodegradation and chemical transformation of pollutants.Hydrogeological characteristics influence the ability of natural attenuation through the differences in permeability,adsorption and desorption capacity caused by the lithologic characteristics of sediments.Groundwater flow rate controls the convection and dispersion of pollutants and affects the dissolution and release of pollutants from sediment to groundwater as well as the kinetic process of biodegradation.In general,due to the complexity of organic matter,mineral and microbial components and the heterogeneity of hydrogeological conditions,the study of the influence of site intrinsic properties on the natural attenuation of pollutants needs to be further strengthened.In particular,we need to identify the spatial and temporal dynamics of pollutant attenuation through long-term site monitoring,and deepen the understanding of the mechanisms underlying the interaction between typical site geochemistry,hydrogeological conditions and pollutants.
作者
赵萌
姜永海
冯帆
贾永锋
廉新颖
尚长健
臧永歌
Zhao Meng;Jiang Yonghai;Feng Fan;Jia Yongfeng;Lian Xinying;Shang Changjian;Zang Yongge(State Key Laboratory of Environmental Criteria and Risk Assessment,Chinese Research Academy of Environmental Sciences,Beijing 100012,China;State Environmental Protection Key Laboratory of Simulation and Control of Groundwater Pollution,Chinese Research Academy of Environmental Sciences,Beijing 100012,China)
出处
《地质科技通报》
CAS
CSCD
北大核心
2023年第3期250-261,共12页
Bulletin of Geological Science and Technology
基金
国家重点研发计划项目(2019YFC1806204)
国家自然科学基金项目(41907178)。
关键词
自然衰减
污染物
有机质
矿物组成
水文地质
微生物降解
地球化学特征
natural attenuation
pollutant
organic matter
mineral composition
hydrogeological condition
microbial degradation
geochemical characteristic
