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1.
氯代挥发性有机物（VOCs）氯同位素测试技术及其在地下水污染中的应用研究进展 总被引：3，自引：0，他引：3
在有机氯污染的研究中,氯同位素（37Cl）的应用能够在原子水平上识别污染源并研究污染机理,为更加有效地研究地下水的有机污染提供了有利的工具。综述了8种氯代VOCs氯同位素的测试方法与技术,论述了氯代VOCs氯同位素在识别地下水污染源、监测有机污染物的降解过程、检验防治措施的修复效果、鉴别氯代VOCs的生产厂商、示踪氯代VOCs在土壤和水体中的迁移和混合过程等方面的应用,认为应尽快在国内研制先进的测试流程,开展有机氯同位素分馏机理的研究,加强应用C和Cl同位素技术对氯代VOCs污染和检测修复效果的研究。 相似文献
2.
在调查华北平原一个污染年限超过35年的石油化工场地时,采用便携式仪器土层测气方法,快速、准确地测定了场地内40多个钻孔不同深度土层中挥发性有机物(VOCs)的浓度。基于对场地地质水文地质条件的认识,以及通过对大量数据的分析对比和应用空间变异分析方法,得出了对场地土层介质中VOCs污染特征的如下认识:(1)土层VOCs浓度的垂向变化可概括为污染源淋滤型、包气带扩散污染型、地下水波动带污染型和混合污染型四种污染类型;(2)在包气带砂土层和粉土层中,VOCs的扩散规律可近似用指数模型描述;(3)包气带土层中VOCs优先积聚在渗透性强的砂性土层中,砂土层中VOCs浓度是粉土层中VOCs浓度的1.5～12倍,平均3.76倍;(4)土层VOCs浓度的水平变异性表现为包气带土层的变异性要比地下水波动带土层大,且水平变异性能在25m尺度内得到充分显示;而土层VOCs浓度的垂向变异性随地而异,变化复杂,很难用统一的一个量化尺度来表征。本文对这一典型污染场地的剖析,有助于从事污染场地调查人员认识我国华北平原石油化工类场地的污染特征,并为调查与治理类似污染场地提供技术依据。 相似文献
3.
选取某农药厂旧厂区为试验场地,考察化学氧化技术异位处理地下水非水相有机污染物的运行效果。基于小试研究,确定高锰酸钾、高铁酸钾、芬顿试剂以及次氯酸钠4种氧化剂在中试试验中的适宜投加量。中试结果表明,当进水流量为1.0 m^3/h时,不同氧化剂对于常规水质指标及特征有机污染物的去除效果存在差异性。总体而言,四种氧化剂对于中长链石油烃类污染物(C10-C36)的去除率可达20%~70%,但对氯代烷烃类污染物的去除效果低于20%;高铁酸钾和次氯酸钠分别对于苯酚类和多环芳烃类污染物的去除效果较好(70%~100%);芬顿试剂对各类污染物均有显著氧化效果,其中对于短链石油烃(C6-C9,去除率20%~40%)、苯系物(去除率40%~90%)的去除效果高于其他三种氧化剂。研究不同氧化剂对于多组分有机污染地下水的处理效果,为将化学氧化技术应用于此类污染场地提供了理论和技术支持。 相似文献
4.
某废弃煤矿竖井经倾倒有机废液,导致环境污染事件,造成巷道及采空区内地下水污染。本文结合场地实际情况,选取倾倒竖井(事故井)及周边区域为中试区域,采用“抽出处理+原位氧化循环”两阶段联合修复技术对污染场地开展中试研究。本文介绍了场地污染概况、地下水修复中试方案设计和实施,以及对修复效果进行评价。结果表明,中试处理后地下水中COD和二氯甲烷最高去除率分别为97.88%和99.74%。中试试验表明, “抽出处理+原位氧化循环”两阶段修复技术,对处理矿区内巷道及采空区等复杂地层结构下深层地下水中有机污染物具有较好的去除效果,可以结合现场实际情形对整个污染场区进行规模应用。 相似文献
5.
某石化污染场地含水层自然降解BTEX能力评估 总被引：1，自引：0，他引：1
地下水污染问题是国家关注的重要环境问题之一,监测与评估含水层自然降解污染物能力是防治地下水污染的基本手段,也是国外地下水中修复技术研究热点课题。以华北平原某石油化工类场地为案例,通过调查场地水文地质条件、土壤及地下水污染现状,监测场地地下水中苯系物(BTEX)浓度及相关化学参数变化,运用微生物水文地球化学方法和水文地质方法,估算了该场地含水层自然降解苯系物量。这一研究成果为评估我国石油类场地地下水污染的自然修复能力提供了实证和基础数据。 相似文献
6.
1,2,4-三氯苯是我国工业污染场地土壤和地下水中典型的有机污染物,具有持久性、生物蓄积性和高毒性特点,对生态环境和人体健康危害巨大。1,2,4-三氯苯密度比水大,容易迁移至深部厌氧区域,因此,开展1,2,4-三氯苯厌氧微生物降解与修复研究具有重要实际应用价值。本文通过长期富集培养,获得一份可以稳定地将1,2,4-三氯苯还原脱氯至1,4-二氯苯,再进一步还原脱氯至氯苯的厌氧菌液。通过16S rRNA基因扩增子测序及引物特异性的定量PCR实验,证明厚壁菌门的脱卤杆菌属细菌(Dehalobacter species)是1,2,4-三氯苯和1,4-二氯苯厌氧还原脱卤的功能菌株,其生长率为(1.68±0.8)×106 copies·μmol-1(释放的氯离子)。通过PCR扩增,获得Dehalobacter菌株的16S rRNA基因序列,构建了系统发育树。本研究可为1,2,4-三氯苯污染场地开展原位厌氧微生物修复提供菌株资源和理论指导。 相似文献
7.
某灰岩矿坑场地受到了有机污染,对当地脆弱的岩溶地下水环境构成威胁。在查明场地周边岩溶发育特征的基础上,结合区域水化学、水动力场调查结果,分析了场地及周边地下水污染特征和污染场地的潜在风险。结果表明：场地内水体受到了萘、氯乙烯、苯酚、邻苯二甲酸二丁酯、PCB52等多种有机物的污染,其中以4-氯-3-甲基苯酚、2,4-二硝基苯酚等酚类化合物含量最高;场地内水体水质兼具地下水特征,水化学类型为Cl·SO4-Na·Ca型,与其相邻的2个矿坑水质已受到影响,水体水化学类型往污染场地水体类型演化;场地周边地下水水质总体较好,仅场地西侧1个地下水井水质受到了污染矿坑的影响。目前,该矿坑场地仍处于水位漏斗恢复期,污染物并无向外迅速扩散的水动力条件,但当矿坑场地流场恢复至天然状态后,矿坑内污染物可通过场地周边的3条岩溶裂隙带-60 m标高以浅的地层向周边迁移,对环境造成了巨大威胁,应采取降低矿坑水位、定期监测矿坑水和地下水水质、实施帷幕灌浆工程等措施防控场地的潜在污染风险。 相似文献
8.
许多有机化合物对人体和生物有毒害作用,其中一些具有"三致作用"。地下水有机污染研究开始于20世纪60—70年代,经过半个世纪的发展,国际上已把地下水污染研究的重点从无机污染物转向有机污染物。在岩溶发育地区,地质环境脆弱,防污能力差,地下水具有易污染性,有机污染物在岩溶地区的分布有别于其他地区。本文以贵阳市某加油站15年前发生的油灌泄漏污染事件为例,通过地面调查、地质雷达、钻探、样品分析和综合研究等方法查明了地下有机污染物的运移规律、分布范围以及地下有机污染物的组分特征。经分析对比1999年、2007年以及2012年的研究成果,结果表明:(1)受岩溶发育形态的影响,场地内有机污染物在地下具有富集与稀释的双重特性;(2)在岩溶管道发育、地下水水头高度低于基岩面的地带,有机污染物组分含量总体呈减少的趋势;(3)在以溶蚀裂隙为主、地下水水头高度高于基岩面的地带,有机污染物不断富集,年扩散速率仅为12 m。 相似文献
9.
为查明场地污染分布特征,需对场地土壤和地下水进行钻探取样,按规范的检测指标进行逐一测试。在初查和详查阶段将获得大量的土壤和地下水污染数据,数据样本数量大、监测指标多,数据结构复杂,如何从场地大数据中提取价值信息已成为研究热点。以某有机污染场地为例,基于自组织映射神经网络（SOM）和K均值算法开展大数据分析,深入探讨地下水和土壤中各污染指标间的相关性。结果表明:（1）基于自组织映射神经网络的大数据分析可快速挖掘复杂多维的污染场地监测数据,有效完成关键信息的提取;（2）地下水中污染检出指标存在显著的聚类特征,同一聚类中的污染指标具备相似的空间分布特征。对场地污染物检测采取先分类后分级的优化筛选策略,减少污染物检测指标数目,从而有效降低场地检测费用;（3）土壤和地下水中污染检出指标存在良好的空间相关性,这与该污染场地地下水渗流速度缓慢有关。土壤和地下水污染检出指标空间分布的相关性,有助于场地污染源的追溯。 相似文献
10.
济南泉域岩溶地下水有机污染特征研究 总被引：11，自引：6，他引：5
对济南泉域岩溶地下水系统水质进行了系统的采样分析。结果表明,泉域岩溶水已普遍受有机物污染,有机污染物检出率高达93%。检出有机物多于5项的样品多分布于大中型企业附近。在所有检出的有机物中,有机氯农药类、卤代烃类检出率最高,分别达到60%、57.8%。尽管岩溶水有机污染较普遍,但有机物含量较低,仅局部地段存在有机物超标现象。泉域岩溶水有机污染特征受控于工业企业分布及地下水流场,在济南侵入岩体南缘附近形成了近长方形的岩溶水有机污染区,面积达156 km2。污染区南部地带是济南市工业集中区,灰岩浅埋,防污性能差。另外由于地下水径流方向与侵入岩体南缘线近垂直,进入灰岩含水层的有机污染物随地下水径流向北运移,造成埋藏于火成岩体之下的埋藏型岩溶水也受到污染。 相似文献
11.
Krishna R. Reddy 《Geotechnical and Geological Engineering》2010,28(3):211-221
Throughout the world, subsurface contamination has become a widespread and pervasive problem. Toxic chemicals such as heavy
metals and organic compounds are commonly used in a myriad of industries. However, largely through inadvertent or accidental
release, these chemicals are presently polluting sites across the United States. In order to protect public health and the
environment, further pollution must be prevented and sites with existing contamination urgently need remediation. Unfortunately,
remediating subsurface contamination has proved to be a daunting task. Heavy metals and organic compounds often coexist and
their distribution within the subsurface is highly dependent on particle and macro-scale heterogeneities. Vast resources have
been invested to develop efficient remediation technologies, yet very few of these technologies have been successful. In-situ
remediation is often preferred due to minimal site disturbance, safety, simplicity, and cost-effectiveness. The effectiveness
of in-situ remediation technologies depends largely on the contaminant chemistry and subsurface heterogeneities (including
particle-scale heterogeneities such as fine-grained soils, soils with reactive minerals, and/or soils rich in organic matter
as well as macro-scale heterogeneities such as irregular soil layers and/or lenses). Under such heterogeneous conditions,
integrated electrokinetic remediation technology has great potential. As a safe and economical remedial option for so many
contaminated sites, the application of integrated electrokinetic remediation offers enormous public health, environmental,
and financial benefits. 相似文献
12.
A. Arjoon A. O. Olaniran B. Pillay 《International Journal of Environmental Science and Technology》2013,10(2):395-412
Chlorinated hydrocarbons can cause serious environmental and human health problems as a result of their bioaccumulation, persistence and toxicity. Improper disposal practices or accidental spills of these compounds have made them common contaminants of soil and groundwater. Bioremediation is a promising technology for remediation of sites contaminated with chlorinated hydrocarbons. However, sites co-contaminated with heavy metal pollutants can be a problem since heavy metals can adversely affect potentially important biodegradation processes of the microorganisms. These effects include extended acclimation periods, reduced biodegradation rates, and failure of target compound biodegradation. Remediation of sites co-contaminated with chlorinated organic compounds and toxic metals is challenging, as the two components often must be treated differently. Recent approaches to increasing biodegradation of organic compounds in the presence of heavy metals include the use of dual bioaugmentation; involving the utilization of heavy metal-resistant bacteria in conjunction with an organic-degrading bacterium. The use of zero-valent irons as a novel reductant, cyclodextrin as a complexing agent, renewable agricultural biosorbents as adsorbents, biosurfactants that act as chelators of the co-contaminants and phytoremediation approaches that utilize plants for the remediation of organic and inorganic compounds have also been reported. This review provides an overview of the problems associated with co-contamination of sites with chlorinated organics and heavy metals, the current strategies being employed to remediate such sites and the challenges involved. 相似文献
13.
为了探究高级氧化技术对土壤中有机氯代烃的氧化降解作用,为ISCO（in situ chemical oxidation）技术体系提供重要的理论依据和数据支撑,考察了热活化过硫酸盐（persulfate,PS）氧化降解不同类型土壤（砂类土壤、黏土类土壤）中挥发性氯代烃污染物（三氯乙烯（TCE）、三氯乙烷（TCA）、顺式-1,2-二氯乙烯（cis-1,2-DCE）、1,2-二氯乙烷（1,2-DCA））的效能;同时,通过硫酸盐与土壤相互作用过程研究,探究了不同土壤介质中有机质和无机组分在过硫酸盐消耗中所占比例。结果表明：在50℃时,热活化过硫酸盐可有效降解土壤中1,2-DCA、cis-1,2-DCE、TCA和TCE,砂类土壤介质中4种氯代烃降解效果依次为25%、89%、5%和61%,黏土类土壤介质中4种氯代烃降解效果依次为35%、86%、8%和63%;4种氯代烃的降解效果从高到低顺序依次为cis-1,2-DCE、TCE、1,2-DCA、TCA,砂类土壤中的氯代烃总体降解效果优于黏土类土壤中氯代烃的降解效果。另外,土壤中过硫酸盐氧化降解氯代烃反应研究发现,砂类和黏土类土壤介质组分中有机质消耗率分别为81.3%和72.6%,铁元素消耗率分别为80.5%和38.6%,表明土壤介质组分与过硫酸盐发生了氧化还原反应,从而导致过硫酸盐自身的大量消耗。由此可知,土壤介质中的有机质、铁元素等矿物质均参与过硫酸盐的消耗过程,且土壤有机质、铁元素与氯代烃之间在消耗过硫酸盐反应上存在竞争关系,土壤组分过多地消耗了过硫酸盐,导致了氯代烃的氧化降解效率较低。因此,针对实际有机氯代烃污染场地,采用过硫酸盐氧化技术进行修复时,过硫酸盐的实际投加量要远高于化学计量值,需充分考虑到土壤组分对过硫酸盐自身的消耗作用。 相似文献
14.
浅层地下水氯代烃污染天然衰减速率的估算 总被引：1，自引：0，他引：1
天然衰减恢复技术是恢复和控制浅层地下水氯代烃污染的技术之一,如何简便获取可靠的氯代烃衰减速率常数是该技术应用的一个关键。趋势线分析方法是一种简便有效的方法,在污染羽状体稳定的条件下,通过地下水流向上至少3口监测井的资料,能够比较准确地估算出污染物的天然衰减速率常数和生物降解速率常数。某氯代烃污染典型区的应用实例研究表明,该区四氯乙烯(PCE)的天然衰减速率常数和生物降解速率常数分别为0·000925d-1和0·000537d-1,证实该区浅层地下水中的PCE存在天然生物降解,但降解速率比较缓慢。忽略吸附作用的天然衰减容量计算所得出的天然衰减速率常数明显小于实际结果,说明尽管典型区包气带及含水层介质的有机碳含量很少,但它们对PCE的吸附作用不容忽视。 相似文献
15.
Ge Chen Yajun Sun Jiayu Liu Shougan Lu Ling Feng Xiang Chen 《Environmental Earth Sciences》2018,77(24):797
The simulation of groundwater flow and solute transport at contaminated sites often neglects the important influence that aquifer heterogeneity can have on the sub-surface distribution of contaminants. In this paper, the method of transition probability for geological statistics (T-PROGS) included in the Groundwater Model System (GMS) was applied to a chlor-alkali-contaminated site that was sampled with 68 soil borings and 15 groundwater monitoring wells. A 3-D groundwater numerical model and solute transport model was developed that was constrained by soil and groundwater data from the site. The spatial distribution of chloroethylene concentrations was simulated for a number of times using the levels measured in the field as a baseline. The results of these simulations showed that shapes and distribution of contaminant plumes are irregular both vertically and horizontally. The solute-transport simulations indicated that much of the contamination will preferentially move in groundwater through silt and fine-sands whereas flow is largely blocked in clays. Consequently, fine sand and silts become the most seriously polluted zones at the site, whereas, areas underlain by clays are largely uncontaminated. Heterogeneous lithologies beneath a site increase the complexity of coupling simulations of soil and groundwater. 相似文献
16.
Organic Contamination of Soil and Goundwater in the Piedimont Plain of the Taihang Mountains 
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下载免费PDF全文 The risk of groundwater contamination following the infiltration of waste surface water, is of great interest, particularly in areas experiencing water shortage. In this study, the distribution characteristics of contaminants along the Cihe River, in the piedimont plain of the Taihang Mountains, China, was investigated by measuring the soil and water samples. The main organic contaminants detected in different media include hydrocarbons, chlorinated hydrocarbons, polycyclic aromatic hydrocarbons, and pesticides. The main contaminants found in different media are mostly derived from the river water, which can be seen from the results of waste water from the river and groundwater, from the soil samples from different depth and distance of the profiles along the river. The distribution characteristics showed that there has been a natural attenuation of the contaminants from the river during their transportation through the soils and groundwater. The sorption of organic compounds to soil organic matter is thought to be a main mechanism of natural attenuation. 相似文献
17.
An Integrated Geostatistical Approach for Contaminated Site and Soil Characterisation 总被引：1，自引：0，他引：1
For several years, abandoned or stopped industrial sites increasingly arouse the interest of politics and investors. Having
a high social and economic estate value, these sites generally reveal contaminated soils that must be remediated first before
receiving any new use. Due to financial, environmental or human health stakes, heuristic methods appear inappropriate because
they do not provide reliable estimations of contaminated soil volumes and ignore spatial uncertainties. Problems at hand may
be very complex, involving multiple correlated contaminants for which spatially varying pollutant grades are to be estimated
and confronted to various regulatory thresholds, depending on redevelopment target areas. In such conditions, geostatistics
provides effective methods to quantify local and global uncertainties about soil contamination and contaminated soil volumes.
By quantifying uncertainties, geostatistical models are useful as support for decision-making about redevelopment scenarios
or remediation techniques. Specific approaches are required, however, to overcome particular modelling issues as related to
the skewness of pollutant grade distributions or change of support. Making use of our practical experience, such an integrated
geostatistical approach is proposed for modelling contaminated sites. It is illustrated by application to a recent actual
case study. 相似文献
18.
Risk Assessment on Organic Contamination of Shallow Groundwater of an Oilfield in Northeast China 下载免费PDF全文
下载免费PDF全文 With the oil contaminated site of an oil field in northeast as the research area, based on the site geological and hydrogeological conditions, and by virtue of the methods of assessment on current situation of organic contamination and environmental impact assessment as well as leaching mobility assessment on organics, the internal and external risk assessments on organic contamination of shallow groundwater in the research area are conducted respectively. According to the results, about 30 kinds of organic components, including chlorinated hydrocarbons, mononuclear aromatics, heteroaromatic compound, polycyclic aromatic hydrocarbon and n-alkanes, are detected in the shallow groundwater in the research area. The current situation contamination of dichloromethane is the most serious, and all well points are of contamination at medium or above level. Compared with dichloromethane, contamination of trichloromethane and benzene is lighter, but several seriously contaminated well points occur in these two groups. The leaching mobility of dichloromethane, trichloromethane and benzene is extremely high, posing the greatest contamination risks against groundwater. 相似文献
19.
This review summarizes over 160 studies focused on soil contamination near non-ferrous metal smelters. The methods of these investigations were examined with an emphasis on the combinations of traditional (geo)chemical approaches with various mineralogical and metal isotope techniques that are particularly helpful for depicting the fate of smelter-derived contamination in the soil. Differences in the distributions and binding of metal(loid)s in smelter-affected soils from temperate and (sub)tropical climatic zones indicate the greater vulnerability of the latter. Prevailing wind direction is a key factor affecting the dispersion of smelter emissions and their subsequent deposition into the soils, with greater importance found especially in arid areas. Whereas the greatest contamination is generally observed in the surface soil layers, downward migration of metal(loid)s in the soil profiles has been documented at numerous sites. Contamination of smelter soils significantly affects both plants and soil organisms, but suitable remediation techniques (such as chemical stabilization of soils by amendments) can be used for reducing the bioavailability of contaminants. 相似文献
20.
D. M. Cocârţă S. Neamţu A. M. Reşetar Deac 《International Journal of Environmental Science and Technology》2016,13(8):2025-2036
Human activities have progressively increased in recent years. Consequently, significant environment deterioration resulted. Soils have a particularly varied vulnerability to heavy metal pollution, especially in the vicinity of industrial areas. Heavy metal contamination of soil may induce risks and hazards to humans and the ecosystem, while toxic metals in soil can severely inhibit the biodegradation of organic contaminants. This paper is focused on human health risk assessment from extremely contaminated soil with heavy metals, mainly with carcinogenic elements. The study refers to an agricultural area in the vicinity of an old metallurgical processing industrial facility. The contaminants evaluated in the present paper are beryllium (Be), cadmium (Cd), chromium (Cr), nickel (Ni) and lead (Pb). Contamination level is pointed out through laboratory analysis results of soil samples taken from 0–0.2 m, 0.2–0.4 m soil layers and up to 2.1 m soil depth. Some heavy metal concentrations (Cd, Cr and Pb) exceed the intervention thresholds for sensitive areas, as they are stipulated in the national regulation in Romania. The identified average concentration levels of Cd, CrVI and Pb in the first layer of the investigated land are 23.83, 7.71 and 704.22 mg/kgd.w, respectively. The results show that the potential risk of human health is relevant (higher than the acceptable one after World Health Organization) and a possible solution for the remediation should become a major concern for the investigated area. 相似文献