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核桃壳滤料广泛应用于油田污水处理,每年因此产生大量的废弃核桃壳滤料,由于将其露天堆砌在地面上,滤料上的污染物在降水、风力、地表径流等的作用下发生迁移,直接影响到堆砌场地周边的土壤、大气、水源的质量。采用标准方法对油田废弃核桃壳滤料上的污染物组成进行分析的结果表明,主要污染物为原油、CaCO3和Cd2＋、Pb2＋重金属离子,污染物总含量较高,与原油组成相比,废弃核桃壳滤料上的芳烃含量增加较多,饱和烃和胶质有所减少。借助一维对流-弥散方程建立了模拟石油类污染物在土壤中迁移转化规律的数学模型,通过室内土柱实验确定模型参数,同时验证模型的准确性。将实验及模拟的结果相结合可知,该模型可以用来模拟石油类污染物在土壤中的迁移规律,符合y=y0＋A1exp（-x/t1）＋A2exp（-x/t2）规律。研究结果为油田废弃滤料对土壤环境的影响及治理提供了参考。 相似文献
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阐述了植物和微生物降解环境中石油污染物及PAHs的重要作用和最新进展。国内外大量实验室研究表明,不同植物和微生物(细菌、真菌和放线菌)联合修复石油污染土壤均得到了较为理想的效果,在某种程度上微生物菌群要优于单一菌株;土壤中植物根系与微生物形成根际效应对污染物的降解起到了促进作用;生物表面活性剂较合成表面活性剂具有更好的生态适宜性和石油污染土壤修复能力;土壤中多组分污染物共同修复虽处于起步阶段,其作用机理也有待进一步研究,但是,发展前景值得期待。目前该领域的研究仍存在一些问题有待解决:植物–微生物菌群降解石油污染物过程中,微生物菌群间协同和竞争机制及试验结果的可重复性尚需证实;实验室研究与大田环境条件的差异,使得目前的研究成果尚需田间试验的验证和支持;根据土壤类型和气候特点,研究极端(高含盐量;氮、磷等营养元素缺乏;低温)条件下的石油高效降解菌株/群,制备有效的便于大田应用的固体菌肥意义重大;同时在确定石油污染物对环境致害的限值的基础上,建立石油污染土壤评价体系也势在必行。 相似文献
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以苏南某焦化厂为研究对象,在对污染区域初步识别的基础上,采集了0～4.5 m深的22个土壤样品和2个地下水样品,利用GC/MS等检测了多环芳烃类、总石油烃、苯系物、重金属,总氰化物、挥发酚、硫化物的含量,并研究了其在不同功能区土壤和地下水中的特征分布。结果表明：（1）该焦化场土壤和地下水受到了不同程度的污染,其中炼焦炉周边、焦油和洗油储罐区、焦油和粗苯加工车间是污染最严重的区域;（2）土壤中主要超标污染物是多环芳烃、总氰化物、总石油烃、单环芳香烃、二苯呋喃、苯胺、硫化物、挥发酚和一些苯酚类化合物;（3）地下水重点污染区域粗苯车间受到总氰化物、苯胺、苯酚类、萘、总石油烃、单环芳香烃的严重污染,污水处理站区域地下水主要污染物包括总氰化物、萘、总石油烃、苯。 相似文献
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[目的]研究石油污染对土壤持水能力及供水强度的影响,为有机污染物在土壤中迁移与转化规律研究提供理论基础。[方法]以陕北采油区的主要土壤类型—轻壤质黄绵土为研究对象,人为模拟获得5个不同梯度的石油污染土壤(0%,0.5%,1%,2%和4%),室内测定土壤水分特征曲线,采用Van Genuchten模型拟合获得模型参数,并以此为基础对比分析不同处理土壤持水能力、水分有效性、比水容量之间的差异。[结果]石油污染引起土壤持水性显著降低,污染浓度越大,持水性越低;对土壤水分特征曲线影响的显著区间主要在水吸力(pF)为1.5的低吸力段和水吸力(pF)为3.5以上的高吸力段,石油污染对土壤结构性的影响更加显著;高浓度的石油污染引起土壤有效水含量下降,加剧了土壤的干燥化程度,不利于协调干旱气候与植物需水性之间的矛盾;随着石油污染浓度的增加,土壤比水容量也呈现出显著递减趋势,土壤可利用水分对应的吸力范围相应变窄。[结论]石油污染显著降低了土壤的持水能力及供水强度,加剧了地区土壤旱情,给植物生产和生态环境带来严重危害。 相似文献
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通过分析九段沙土壤及附近水域石油类物质的时空分布,研究了土壤石油类污染现状及其来源特征。结果表明:九段沙土壤石油类物质以碳原子数小于10的烷烃和芳香烃类为主,有少量烯烃、羧酸及含氧杂环化合物。土壤石油烃类平均含量为23.98mgkg-1,单因子污染指数在0.431～0.525,污染样本超标率为0,目前土壤石油类污染尚处于清洁水平。土壤石油类物质含量沿高程有显著变化,中潮滩最高,光滩最低;其季节性差异显著,表明湿地土壤有外源石油类物质的输入;夏秋两季含量较高,与期间频繁的海上作业及陆源污染相关;经监测,九段沙附近水域石油类污染含量为0.246～0.309mgL-1,其季节差异明显、且涨潮>落潮,表明九段沙土壤石油类污染主要来自外围水域,水体石油类物质在湿地有部分沉积。 相似文献
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高矿化度油田废水污染农田现状调查与评价 总被引：2，自引：0，他引：2
江汉油田采油井在钻矿和采油时有少量高矿化度废水与石油洒落地面,导致土壤污染,造成农作物减产。对湖北省潜江县周矾农场不同污染程度的时地农田和水田污染现状及污染物在土壤中的迁移状况进行了调查研究。结果表明,污染农田土壤的主要污染物是氯化物、盐类,其次为石油和Ｃｄ。氯化物、盐类污染水田耕层含量底层,旱地农田则反之。受污染的土壤和下降。 相似文献
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石油污染物对山东省三种类型土壤微生物种群及土壤酶活性的影响 总被引：3，自引：0，他引：3
利用胜利油田开采区的含油污泥,对山东省三种主要类型的土壤混入不同含量的含油污泥后造成的微生态变化进行了试验研究,从土壤微生物种群数量和土壤酶活性的角度评价了含油污泥对土壤生态系统的影响。结果表明三种不同类型的土壤,其微生物区系和部分土壤酶活性受不同含量的石油污染物影响程度不同。其中棕壤的微生物区系受土壤总石油烃TPH(Total petroleum hydrocarbon)的变化影响较小,对石油烃造成的微生态影响的修复能力较强,可以作为植物修复石油污染土壤的首要选择土壤类型。石油烃含量对三大类微生物类群变化的影响,以放线菌最为显著,当土壤石油烃含量为500mgkg-1时,潮土、褐土和棕壤的放线菌总数分别下降了80%、85%和89%,石油烃含量对褐土和棕壤真菌数量的影响较小。三种类型土壤淀粉酶和脲酶酶活性随石油烃含量的变化表明,潮土和褐土的淀粉酶酶活性受石油烃含量影响显著,可以作为这两类土壤石油污染程度的敏感生化指标。 相似文献
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Using the soil gas radon as an indicator for ground contamination by non-aqueous phase-liquids 总被引：1，自引：0，他引：1
Michael Schubert Klaus Freyer Hans-Christian Treutler Holger Weiß 《Journal of Soils and Sediments》2001,1(4):217-222
1 The Problem One of the major problems facing risk assessment at polluted industrial sites and military bases is subsurface contamination
by non-aqueous phase-liquids (NAPLs), since tracing the extent of a NAPL plume using conventional methods (drive point profiling)
is usually associated with difficulties. In an effort to trace subsurface contamination as precisely as possible, monitoring
points are placed in the area that might be affected by contaminants, and groundwater and soil samples are taken to the laboratory
for analysis. However, the final number of monitoring points is hardly ever sufficient for distinctive contamination mapping,
and this may ultimately result in an unsuitable remediation action being taken.
2 Objectives To obtain a more detailed image of a subsurface NAPL plume and, hence, to facilitate remediation measures that are best suited
for the site in question, a denser network of monitoring points is desirable. The aim of the investigation described in this
paper was therefore to develop a new detection method for subsurface NAPL contamination, which is based on an easily accessibleindicator for NAPLs rather than on the analysis of soil and groundwater samples taken at the site. Based on the good solubility of
radon in NAPLs, the idea was put forward that subsurface NAPL contamination should have an influence on the natural radon
concentration of the soil gas. Provided this effect is significant, it would be possible to carry out a straightforward radon
survey on an appropriate sampling grid covering the suspected site and thus enabling the NAPL contamination to be detected
by the localization of anomalous low radon concentrations in the soil. The overall aim of the investigation was to assess
the general suitability of the soil-gas radon concentration as an indirect tracer for NAPL contamination in the ground.
3 Methods The partitioning coefficient KNAPL/air is one of the most influential parameters governing the decrease of the radon concentration in the soil gas in the presence
of a subsurface NAPL contamination. Since NAPL mixtures such as gasoline, diesel fuel and paraffin are among the most important
NAPLs regarding remediation activities, laboratory experiments were performed to determine the radon-partitioning coefficient
for these three NAPL mixtures.
Field experiments were carried out as well. The aim of the field experiments was to test the use of the soil-gas radon concentration
as a tracer for NAPL contamination on-site. For the field experiments, each site was covered with a suitable grid of soil
gas sampling points. Finally, the lateral radon distribution pattern achieved on each of the sites was compared to the respective
findings of the earlier research performed by conventional means.
4 Results and Discussion The results of the laboratory experiments clearly show a very strong affinity of radon to the NAPL mixtures examined. The
partitioning coefficients achieved correspond to those published for pure NAPLs (Clever 1979) and are thus in the expected
range. The results of the field experiments showed that the minimum radon concentrations detected match the respective NAPL
plumes traced previously.
5 Conclusions Both the results of the lab experiments and the on-site findings demonstrate that the soil-gas radon concentration can be
used as an indicator for subsurface NAPL contamination. The investigation showed that NAPL-contaminated soil volumes give
rise to anomalous low soil-gas radon concentrations in the close vicinity of the contamination. The reason for this decrease
in the soil-gas radon concentration is the good solubility of radon in NAPLs, which enables the NAPLs to accumulate and ‘trap’
part of the radon available in the soil pores.
6 Recommendations and Outlook Further research is required into contamination with rather volatile NAPLs such as BTEX. Further research is also needed to
examine whether it is possible to not only localize a NAPL plume, but also to obtain some quantitative information about the
subsurface NAPL contamination. The authors also believe that additional investigations should be carried out to study the
ability of the method to not just localize a NAPL contamination, but also to monitor on-site, clean-up measures. 相似文献
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A comparative analysis of the changes in the properties of the soils and soil biota in the past ten years along the gradient of pollution with aerotechnogenic emission from the Kandalaksha aluminum smelter in response to a decrease in the emission volume has been performed. The concentrations of fluorine compounds (the priority pollutant) in the emissions and in the organic soil horizons in the impact zone significantly decreased in 2011 relative to 2001. The concentrations of Al decreased only in close vicinity to the smelter (up to 2 km). The concentrations of F, Ca, and Mg in the liquid phase were higher than those in the solid phase, and these elements migrated to greater distances from the source of the contamination (up to 15–20 km). The elements Si, Al, Fe, and P were contained mostly in the solid phase and were mainly deposited within the 5-km zone. The acidity of the litter near the smelter decreased by almost by two pH units in the nearest zone (<2 km). The decrease in the amount of contaminants in the emissions resulted in the narrowing of the zone of the maximum soil contamination from 2.5 to 1.5 km from the emission source; the zones of strong and moderate contamination narrowed by 5 km. The regularities of the changes in the numbers and biomasses of the main groups of microorganisms in the soils of the permanent sampling plots did not change during the past ten years. The emissions inhibited the development of the fungal biota. The prokaryotic part of the soil microbiota and, particularly, the actinomycetes proved to be tolerant to the emitted contaminants. It was suggested that the changes in the structure of the fungal and actinomycetal communities should be used to monitor the state of the soil ecosystems affected by the emissions from the aluminum smelter. 相似文献
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Chuang Yu Zezhong Ren Junfeng Liu Xiaoqing Cai Jianjun Ma Xiaoniu Yu 《Water, air, and soil pollution》2018,229(10):323
For the understanding of contaminant transport and transformation through landfill liner soils, most models are proposed with one-dimensional solutions. However, for large-scale contamination analysis, the one-dimensional analytical equations are not valid owing to the restriction of contaminants moving in horizontal direction. Thus, semi-analytical solutions for two-dimensional transport and transformation of contaminants through soil media with the consideration of large-strain deformation have been developed. To achieve this, Gibson’s large-strain consolidation theory is applied to capture the deformation of soil media under loading, with self-weight effects being taken into account. Transport and transformation of dissolved or sorbed contaminates in fully saturated finite soil medias are captured by extending a well-developed advection-dispersion model in two-dimensional space. The proposed analytical solutions are validated through simulating the process of coupled transport-transformation process of contaminants and consolidation of a finite soil layer. Profiles of contaminant concentration for different cases have been compared and discussed. The resulting simulation shows that large-strain deformation would restrict the transport and transformation of contaminants significantly, in both horizontal and vertical directions. Parameter studies also indicate that, with the increasing depth of soil layer, the breakthrough time for contaminants increases dramatically; diffusion coefficients affect the two-dimensional distributions of contaminant concentration and fate of contaminant in layered soil significantly. The numerical findings of this study can provide proper suggestions for the design of landfill liners. 相似文献
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我国有机污染场地现状分析及展望 总被引：1，自引：0，他引：1
以有机污染场地为研究对象，调查分析了全国277个有机污染场地的行业类别、污染类型以及有机污染物种类分布情况，发现主要贡献行业为化学原料及化学品制造行业，贡献率为37.9%；污染类型中以各类有机污染物复合污染为主；除了不同有机污染物之间的相互复合，有机污染物与重金属复合污染特征明显，占总场地58.5%。有机污染物种类分布中多环芳烃类污染场地最多，占54.9%，与欧美有机污染场地中氯代烃类污染场地占比最多不同；其次为总石油烃和苯系物，占比分别为49.5%和36.8%。全国典型地理区域的有机污染特征和污染物超筛选值结果表明，总体上南方有机污染场地数目多于北方，东部经济发达地区场地数目明显多于经济发展中地区，西南和中南地区有机污染与重金属复合污染特征明显。各区域内污染物种类分布与行业相关性强，如多环芳烃污染多在各地区焦化厂场地中出现，总石油烃与重金属复合污染出现在机械制造和金属冶炼行业场地；氯代烃类污染物出现在氯碱生产相关场地；多氯联苯、多溴联苯醚、二噁英等污染出现在电子废弃物拆解集中区。通过对全国有机污染场地的分析和各地区污染特征的讨论，以期为开展污染场地环境调查与修复提供一定的参考，并为污染场地的监督与管理等工作提供依据。 相似文献
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Changhwan Cho Kijune Sung M. Yavuz Coapcioglu Malcolm Drew 《Water, air, and soil pollution》2005,167(1-4):259-271
To devise effective procedures for the remediation of soil contaminated by VOCs, an improved understanding of their fate and transport mechanisms in soil is essential. To show the effect of plants on the dissipation of 1,1,1-trichloroethane (TCA), trichloroethylene (TCE) and tetrachloroethylene (PCE), two types of experiments, vial and column, were conducted. The results suggested that keeping the soil moisture content at field capacity is desirable for VOCs dissipation. All VOCs were dissipated quickly in unplanted columns than planted conditions in early periods of the experiment because more volatilization occurred in unplanted conditions. The plants could take up and retard volatile contaminants, and prevent contamination of ambient air. Although the time for acclimation for microbial communities to contaminants for enhanced biodegradation should be considered, phytoremediation is potentially a cost-effective remediation technique for soils contaminated by volatile organic compounds (VOCs). 相似文献
16.
Kai Wang Zhiqiang Zhu Huagang Huang Tingqiang Li Zhenli He Xiaoe Yang Ashok Alva 《Journal of Soils and Sediments》2012,12(4):556-564
Purpose
Soil contamination by multiple organic and inorganic contaminants is common but its remediation by hyperaccumulator plants is rarely reported. The growth of a cadmium (Cd) hyperaccumulator Sedum alfredii and removal of contaminants from Cd and polycyclic aromatic hydrocarbons (PAHs) co-contaminated soil were reported in this study. 相似文献17.
Soil contamination by organic and inorganic pollutants at the regional scale: the case of Piedmont,Italy 总被引：1，自引：1，他引：0
Gabriele Fabietti Mattia Biasioli Renzo Barberis Franco Ajmone-Marsan 《Journal of Soils and Sediments》2010,10(2):290-300
Background, aim, and scope
Diffuse soil contamination has often been neglected in scientific literature, as most studies focus on contaminants from point-sources (either of industrial or agricultural origin). However, soil pollution from diffuse sources is recognized as one of the major soil threats by the EU Soil Thematic Strategy. In fact, some pollutants are nowadays ubiquitarious in the soil system, and they have to be considered for the implementation of environmental legislation, the definition of clean-up values in remediation activities and, more generally, for a sustainable management of rural areas. In the literature large scale studies on diffuse contamination are few and scattered and often do not consider a wide range of contaminants, the effect of land use, the vertical variability and the potential natural contribution. Aim of this work was to provide an overview of the diffuse soil contamination on a regional scale for a large set of contaminants. Soil inorganic (Cd, Cr, Ni, Pb, Cu, Zn) and organic contaminants (polychlorinated dibenzo-p-dioxins(PCDD), polychlorinated biphenyls (PCBs), and polycyclic aromatic hydrocarbons (PAHs) as well as other soil general parameters were investigated on a 18 × 18 km grid covering a whole Italian region heavily industrialized and intensively cultivated. Soils were sampled at different depths both for natural–undisturbed soil and for agricultural–plow soil. Differences in the trends of investigated contaminants, as a consequence of land use, vertical variability, natural or geogenic origin, relationships among contaminants, and with main soil properties, were explored by means of enrichment factors, bi- and multi-variate statistics. 相似文献18.
Soil contamination by mixtures of petroleum hydrocarbons and heavy metals is common in urban and industrial localities. Interactions between these contaminants have an impact on the mobility and the management of contamination. We have characterized the modifications to the transport of heavy metals (Cd, Cu, Pb, Zn) in soil induced by residual light non‐aqueous phase liquid (LNAPL) for two conditions of trapping. Experiments on the elution of tracers and heavy metals in columns of soil were performed with a glaciofluvial material as the soil. Tracer experiments were modelled with the mobile–immobile (MIM) system of partial differential equations. The experiments were designed to compare water flow and metal transport in LNAPL‐contaminated soil with a control set. Residual LNAPL was trapped in water‐saturated and dry soil to ensure preferential wettability of soil surfaces, namely either water‐wet or LNAPL‐wet. In water‐wet soil columns, LNAPL decreased water flow by two orders of magnitude and increased the fraction of immobile water. Solute residence times (SRTs) suggested that heavy metals resided mainly in mobile water where the reaction time was sufficient to reach steady‐state retention. The SRTs also indicated that a fraction of the heavy metal flux diffused to the immobile water where its retention was limited by diffusion. Retention of heavy metals was significantly greater than in the control columns. In LNAPL‐wet soil columns, the obstruction of small pores and surface coating by residual LNAPL significantly decreased the attenuation capacity of the soil by decreasing the diffusion of heavy metals to immobile water and surface sites. Evidently, the individual behaviour of heavy metals can be significantly modified by non‐miscible organic contaminants. These modifications can have important implications for risk evaluation, contamination management and in situ remediation of soil that is contaminated by mixtures of petroleum hydrocarbons and heavy metals. 相似文献
19.
Human health risk due to consumption of vegetables contaminated with carcinogenic polycyclic aromatic hydrocarbons 总被引：2，自引：0，他引：2