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1.
Greenhouse tests were conducted to study the effect of chelates on the phytoextraction of cadmium and lead, and the rhizodegradation of used engine oil present as a mixed contaminant in a sandy soil. Indian mustard plants were grown in test pot soil for 30 days and chelates ethylenediamine tetraacetic acid (EDTA) and ethylenediaminedisuccinic acid (EDDS) were individually applied to the test soil. The soil was spiked earlier with 50 mg kg?1 of CdCl2, 500 mg kg?1 of PbCl2 and 500 mg kg?1 of used engine oil to form the mixed soil contaminant. At the same concentration of chelates, EDTA was found to be more effective than EDDS in increasing the concentration of metal contaminants Cd and Pb in the plant. Compared to EDDS, EDTA was also more effective in promoting rhizodegradation of the organic contaminant formed by used engine oil. The study demonstrated that the application of chelates to soils containing mixed contaminants such as heavy metals (Cd and Pb) and organics (used engine oil) can simultaneously assist metal accumulation at higher concentrations in the biomass of Indian mustard plant and also reduce the amount of used engine oil in the soil through rhizodegradation.  相似文献   

2.
Bioremediation is an effective measure in dealing with such contamination, particularly those from petroleum hydrocarbon sources. The effect of soil amendments on diesel fuel degradation in soil was studied. Diesel fuel was introduced into the soil at the concentration of 5 % (w/w) and mixed with three different organic wastes tea leaf, soy cake, and potato skin, for a period of 3 months. Within 84 days, 35 % oil loss was recorded in the unamended polluted soil while 88, 81 and 75 % oil loss were recorded in the soil amended with soy cake, potato skin and tea leaf, respectively. Diesel fuel utilizing bacteria counts were significantly high in all organic wastes amended treatments, ranging from 111 × 106 to 152 × 106 colony forming unit/gram of soil, as compared to the unamended control soil which gave 31 × 106 CFU/g. The diesel fuel utilizing bacteria isolated from the oil-contaminated soil belongs to Bacillus licheniformis, Ochrobactrum tritici and Staphylococcus sp. Oil-polluted soil amended with soy cake recorded the highest oil biodegradation with a net loss of 53 %, as compared to the other treatments. Dehydrogenase enzyme activity, which was assessed by 2,3,5-triphenyltetrazolium chloride technique, correlated significantly with the total petroleum hydrocarbons degradation and accumulation of CO2. First-order kinetic model revealed that soy cake was the best of the three organic wastes used, with biodegradation rate constant of 0.148 day?1 and half life of 4.68 days. The results showed there is potential for soy cake, potato skin and tea leaf to enhance biodegradation of diesel in oil-contaminated soil.  相似文献   

3.
菌根真菌对土壤中有机污染物的修复研究   总被引：12，自引：0，他引：12  
菌根真菌是真菌与植物之间特殊的联合共生体，利用菌根真菌修复土壤，尤其是修复有机污染物污染的土壤，正成为一个崭新的研究方向。菌根真菌是土壤真菌的一种，但与土壤中放线菌和细菌等微生物相比，其对土壤中有机污染物具有更大的忍耐能力，并且能利用土壤中大多数持久性有机污染物作为碳源来获取能量。综述了近20年菌根真菌对土壤有机污染物降解研究，讨论了菌根真菌降解土壤有机污染物的可能机制，并探讨了从引入固氮菌、外源细菌两个方面对菌根调控以提高修复效果的可能性，为进一步研究菌根真菌生物降解土壤中持久性有机污染物、利用菌根植物修复有机污染土壤提供信息。  相似文献   

4.
In this paper, the contents of polycyclic aromatic hydrocarbons (PAHs) in soil samples around three different oily sludge plants in winter were analyzed by high performance liquid chromatography (HPLC) and the pollution degree with PAHs in soil samples was determined. Soil samples were collected from the agricultural soil around three different oily sludge plants (the Third Wenming Plant, the Third Mazhai Plant, and the Fourth Wener Plant) along with the leeway in Zhongyuan oil field. The distances from collected sample sites to oily sludge plants are 10, 20, 50, 100, 200, and 500 m, respectively. The results show that the contents of PAHs in soil samples decrease dramatically with the increase of the distance from the oily sludge, and that the PAHs with 2–4 rings are major pollutants in the oily sludge and soil samples. The main factors, which influenced the distribution of PAHs are discussed. Based on Nemero Index P, the classification evaluation shows that the soils around the oily sludge are heavily polluted in winter. The health risk assessment and ecological risk assessment of the soils around the oily sludge in Zhongyuan oil field in winter are analyzed.  相似文献   

5.
Diesel oil is one of the derivatives of crude oil which resistance to biodegradation due to its complex structure and low solubility in water. A novel concept of enhancement of diesel degradation using floating water droplet is proposed and being investigated to address some key challenges encountered in diesel oil spillages in the aqueous area and wetlands. This study aims to increase the floatability of a floating water droplet on oil. A droplet containing a mixed consortium of 60 different hydrocarbon degrading bacteria and sodium dodecyl sulfate as a surfactant was deposited on the diesel oil surface. Contact angle and contact radius were monitored to observe the effect of bacterial activities on the droplet. The behavior of this droplet on diesel oil was different to a previous study with paraffin oil. In particular, the floatability, bacterial growth and biofilm formation demonstrate significant deviation due to the diesel interactions with biological processes. Nevertheless, the results show this method increase microbial activities within the droplet. The result verifies the applicability of the floating water droplet as an environmentally friendly method for diesel oil spillages.  相似文献   

6.
Sorption of three surfactants and personal care products in four types of commonly occurring Indian soils was extensively studied. The soils used in the study were red soil, clay soil, compost soil and sandy soil as classified by American Society for Testing and Materials (ASTM). The three surfactants used in the study were representative of cationic, non-ionic and anionic surfactant groups. The sorption of surfactants followed the descending order: sodium dodecyl sulphate (SDS) > trimethyl amine (TMA) > propylene glycol (PG). The maximum adsorption capacity (Qmax) was obtained in compost soil (28.6 mg/g for SDS; 9.4 mg/g for TMA and 4 mg/g for PG). The rate of adsorption was the maximum in compost soil followed by clay and red soils, and minimum for sandy soils. It is found that the Freundlich model fits the isotherm data better than the Langmuir model. Freundlich coefficient (K f) increased as the organic content of soils increased. Desorption of target pollutants in tap water was 20–50% whereas acid desorbs 40–90% of target pollutants from soil matrix. It was also found that the adsorption and desorption were significantly affected by the presence of clay and organic matter. The results also indicate that surfactants and personal care products, especially TMA and PG, are highly mobile in sandy soil followed by red soil. Therefore, immobilization of target pollutants is most economical and effective in compost and clayey soils whereas for other type of soils the combination of physiochemical and biological process will be effective option for remediation.  相似文献   

7.
张鹏  李春城  李国玉  王学力  王飞 《冰川冻土》2016,38(5):1325-1331
多年冻土区石油污染物迁移过程和特点、污染定量评价、防治和治理措施研发,都是目前寒区经济发展和能源开发迫切需要解决的重要课题.通过室内试验对土体温度场分布、水分分布和石油总量分布的监测分析,研究了冻融循环作用对迁移过程的影响机制.试验结果表明,冻融循环作用通过影响石油污染物本身的物理性质、土颗粒对石油污染物的吸附作用和土体内水相的分布和相状态,影响了石油污染物的迁移过程.原油黏度随温度的降低逐渐增加,使得原油在土体中的迁移能力降低.冻融循环是油水迁移的主要驱动力之一,随着冻融循环的增加,石油污染物和水分向上迁移并聚集,石油随土样高度增加逐渐减小,而水分随高度增加而增加且在一定的位置聚集.研究成果可为多年冻土区石油污染迁移过程和定量评价及防治治理提供重要基础和参考.  相似文献   

8.
The objective of this study was to evaluate the effect of water-cement ratio and cement content on the hydraulic behavior of soil–cement–bentonite (SCB) and soil–bentonite (SB) mixtures permeated with water and diesel oil, to assist with the design of vertical cutoff walls constructed with those mixtures. The experimental program included unconfined compression tests, hydraulic conductivity tests and X-ray diffraction analysis. The test results indicated changes in hydraulic conductivity take place due to the variation of the water-cement ratio and permeant fluid. The hydraulic conductivity of the SB mixtures permeated with diesel oil was higher than the hydraulic conductivity of the same samples permeated with water. X-ray diffraction analyses suggest that this might be due to the decrease in double layer thickness and increase of seepage pore space imparted by diesel oil permeation. Conversely, Portland cement addition increased the hydraulic conductivity of the SCB specimens permeated with water, whereas subsequent diesel oil permeation reduced the hydraulic conductivity of the SCB specimens; this might be due to the relatively lower impact imparted by diesel permeation on the double layer characteristics of the bentonite stabilized with Portland cement.  相似文献   

9.
The ability of native bacteria to utilize diesel fuel as the sole carbon and energy source was investigated in this research. Ten bacterial strains were isolated from the oil refinery field in Tehran, Iran. Two biodegradation experiments were performed in low and high (500 and 10000 ppm, respectively) concentration of diesel fuel for 15 days. Only two isolates were able to efficiently degrade the petroleum hydrocarbons in the first test and degraded 86.67% and, 80.60 % of diesel fuel, respectively. The secondary experiment was performed to investigate the toxicity effect of diesel fuel at high concentration (10000 ppm). Only one strain was capable to degrade 85.20 % of diesel fuel at the same time (15 days). Phenotype and phylogeny analysis of this strain was characterized and identified as diesel-degrading bacteria, based on gram staining, biochemical tests, 16S rRNA gene sequence analysis. These results indicate that this new strain was Bacillus sp. and could be considered as Bacillus Cereus with 98 % 16 S rRNA gene sequence similarity. The results indicate that native strains have great potential for in situ remediation of diesel-contaminated soils in oil refinery sites.  相似文献   

10.
According to the engineering features of the proposed power plant and the possible pollution accidents, the accident conditions of two kinds of polluted groundwater, such as the light diesel oil tank bottom leakage and the power plant pond bottom leakage are set up. Using the two-dimensional hydrodynamic dispersion equation of the continuous injection and instantaneous injection, the groundwater pollution in the accident condition is predicted and evaluated. The results show that, with the passage of time, the migration range of groundwater pollutants caused by sewage leakage from industrial wastewater buffer tank shows a trend of gradual expansion; however, the maximum value of pollutant concentration exceeding standard is gradually decreasing. After 10 years, the excessive pollutant migration distance has reached 390 m. If no remedial measures are taken in time, during the operation of the power plant, industrial wastewater pool sewage leakage will cause long-term pollution to the groundwater. Similarly, if the accident was diesel tank explosion, the range of diesel contamination to groundwater is also increasing over time, but the concentration of pollutants is gradually decreasing. About 25 years later, the pollutant concentration within 400 m downstream of pollution source has decreased to 0.04 mg/L, and the impact of diesel oil leakage on groundwater has largely disappeared.  相似文献   

11.
Performance and pollutants features of Jatropha–Mineral Turpentine blends along with diesel have been examined in a single-cylinder compression ignition engine. Vegetable oils have higher viscosities than diesel fuel, and it greatly disturbs the performance, durability, burning and discharge features of the compression ignition engine. The tests were performed with different blend combinations of Jatropha–Mineral Turpentine oil as fuel. The experimental outcome indicates that brake thermal efficiency of the blend of 80% Jatropha Biodiesel and 20% of Mineral Turpentine is nearby to diesel fuel at 75% load. Carbon monoxides, hydrocarbons and emission were reduced to the considerable amount, whereas the oxides of nitrogen increase with increase in part load and reduced with 75% and full load operations. The specific fuel consumption of Jatropha–Mineral Turpentine blends found to be slightly upper than diesel fuel. The heat release rate and cylinder pressure of Jatropha–Mineral Turpentine blends were closer to diesel fuel. The test results recommend that Jatropha–Mineral Turpentine blends might stay a decent auxiliary to diesel fuel in the near upcoming and it can be concluded that Jatropha–Mineral Turpentine oil blends could be utilized in a conventional compression ignition engine with no alteration.  相似文献   

12.
Among all environmental contaminations, industrial oil is one of the major pollutants of soil, water, and air. There are different chemical, physical, and biological methods to remove all types of oil pollutions. One of the common biological methods is to utilize the microorganisms like yeast, fungi or bacteria. Previous studies concerning the biodegradation of an aromatic compound in industrial waste water by Aspergillus niger have been reported. In this study, we tried to identify an oil-derived microorganism and evaluate its efficacy on self-removal of industrial oil. Firstly, the strain of isolated fungus from various bulks of used oil was defined via colonial identification and DNA sequencing. Secondly, bioremoval activity of defined fungus (Penicillium commune) was evaluated using gas chromatography–mass spectrometry. The optimum conditions in biological elimination of oil including the incubation time, pH level of culture, and amount of reagents were determined. In the best condition, a removal rate of 95.4 % was obtained.  相似文献   

13.
本文在对胜利油田陆上采油区水文地质条件和污染源现状分析的基础上,对浅层地下水和包气带土壤进行了样品采集、污染物组分测试及污染程度研究,分析研究结果表明:胜利油田陆上采油区浅层地下水和土壤已普遍受有机物污染并形成多个有机污染区,检出的有机污染物达16种之多,个别有机物含量还很高.浅层地下水污染程度受到油田采油井数量、采油...  相似文献   

14.
Pollution of petroleum hydrocarbons, in particular oil spills, has attracted much attention in the past and recent decades. Oil spills influence natural microbial community, and physical and chemical properties of the affected sites. The biodegradation of hydrocarbons by microorganisms is one of the primary ways by which oil spill is eliminated from contaminated sites. One such spill was that of the Russian tanker the Nakhodka that spilled heavy oil into the Sea of Japan on January 2, 1997. The impact of the Nakhodka oil spill resulted in a viscous sticky fluid fouling the shores and affected natural ecosystems. This paper describes the weathering of hydrocarbon-degrading bacteria （genus Pseudomonas） and crystallized organic compounds from the Nakhodka oil spill-polluted seashores after nine years. The Nakhodka oil has hardened and formed crust of crystalline paraffin wax as shown by XRD analysis （0.422, 0.377, and 0.250 nm d-spacing） in association with graphite and calcite after 9 years of bioremediation. Anaerobic reverse side of the oil crust contained numerous coccus typed bacteria associated with halite. The finding of hydrocarbon-degrading bacteria and paraffin wax in the oil crust may have a significant effect on the weathering processes of the Nakhodka oil spill during the 9- year bioremediation.  相似文献   

15.
广西红黏土分布区柴油泄漏对土体造成了一定程度污染,为研究轻质非水相非极性柴油孔隙液对红黏土力学性质的影响,本文以0#柴油为添加剂对其重塑样进行不排水快速直剪试验,测得了不同含水率、含油率、法向压力下红黏土抗剪强度及其参数变化规律。研究结果表明:在土-水-油系统中,非极性柴油孔隙液对红黏土强度影响相对较小,且受含水率影响。同一含油率时,红黏土抗剪强度、内摩擦角、黏聚力均随含水率增加而降低;同一含水率时,法向压力影响柴油作用模式,随含油率增加,抗剪强度参数变化较为复杂,当含水率为20%,红黏土内摩擦角、黏聚力反向波动变化;同一含湿率时,柴油比例的提高导致红黏土抗剪强度参数的增大。扫描电镜观察发现,非极性柴油孔隙液的介入,改变了水-土系统的静电及结构模式,导致红黏土强度发生变化,通过所建的“多尺度多阶段柴油作用微结构模型”,阐明了柴油孔隙液对红黏土强度特性影响的微观机理。  相似文献   

16.
Experimental study of enhanced in-situ micro-ecological remediation of petroleum contaminated loess soil was carried out in Zhongyuan oil production areas, and the enhanced in-situ micro-ecological remediation technique includes optimistic in-situ microbial communities, physical chemistry methods, alfalfa planting and regulation of soil environmental elements. Experiments showed that the oil content in the contaminated soil with oil content about 2 898.25 mg/kg can be reduced about 98.61% after in-situ micro-ecological remediation for 99 days, which demonstrated the effectiveness of in-situ micro-ecological remediation methods for petroleum contaminated soil in central plains of China, and explored the practical and feasible application of these methods.  相似文献   

17.
植物根系可以显著提升土体的强度。为探究紫花苜蓿根系对黄土抗剪性能的增强作用,选取生长周期为60 d的紫花苜蓿根系?黄土复合体为研究对象,通过剪切试验和根系拉伸试验获取紫花苜蓿根系?黄土复合体抗剪强度和根系抗拉强度参数,采用电子放大镜观察紫花苜蓿根系结构与特征,利用经验公式建立根?土复合体库仑修正模型,并对比分析库仑修正模型、WWM模型及修正WWM模型的优缺点,对黄土地区植物根系增强土体强度进行评价。结果表明:紫花苜蓿根系对土体抗剪性能的增强效应显著;紫花苜蓿根系发达,根径在0.2~6.7 mm,随着根径的增大,单根极限抗拉力呈指数式增大,抗拉强度呈指数式降低;不同RAR(Root Area Ratio,即根系横截面积之和与土体横截面积的比值)下的根?土复合体抗剪强度相比素土样提升显著,RAR与黏聚力和内摩擦角之间具有显著的相关关系,其中RAR与黏聚力之间呈线性正相关关系,与内摩擦角之间呈高斯函数关系;根?土复合体库仑修正模型对黄土区草本植物根?土复合体的抗剪强度增量预测具有较好的合理性、有效性及适用性,修正WWM模型次之,WWM预测精度相对较差;而在木本植物根?土复合体的抗剪强度增量预测方面,根?土复合体库仑修正模型和修正WWM模型的预测精度要远高于WWM模型。研究结果对黄土地区植被护坡工程具有指导意义。   相似文献   

18.
Crude oil and its derivatives because of different events and accidents may cause pollution to the environment. A biological treatment is a novel technique that uses microorganisms to remove or neutralize pollutants from a contaminated site. Oil-contaminated soils were sampled, after isolating of soil bacteria, using quantitative and qualitative screening, biosurfactant-producing bacteria were identified and environmental factors on the growth of bacteria and biosurfactant were investigated. In this study, the Bacillus subtilis was identified as the best biosurfactant-producing strain which has the ability to grow in environments with high salinity and temperature and pH > 5. The produced biosurfactant from B. subtilis is stable to changes in temperature and salt concentration and pH (in the range of 5–12).The B. subtilis also showed that they are able to biodegrade aliphatic alkanes. The B. subtilis has necessary potential for bioremediation of oil pollution in the environment.  相似文献   

19.
ISC-AERMOD dispersion model was used to predict air dispersion plumes from an diesel power plant complex. Emissions of NO2and SO2from stacks (5 numbers) and a waste oil incinerator were studied to evaluate the pollutant dispersion patterns and the risk of nearby population. Emission source strengths from the individual point sources were also evaluated to determine the sources of significant attribution. Results demonstrated the dispersions of pollutants were influenced by the dominant easterly wind direction with the cumulative maximum ground level concentrations of 589.86 μg/m3 (1 h TWA NO2) and 479.26 μg/m3 (1 h TWA SO2). Model performance evaluation by comparing the predicted concentrations with observed values at ten locations for the individual air pollutants using rigorous statistical procedures were found to be in good agreement. Among all the emission sources within the facility complex, SESB-Power (diesel power plant) had been singled out as a significant source of emission that contributed >85% of the total pollutants emitted.  相似文献   

20.
On the basis of site investigation and sample collection of petroleum contaminants in the soil-water-crop system in the Shenyang-Fushun sewage irrigation area, the physical-chemical-biological compositions of the unsaturated zone is analyzed systematically in this paper. At the same time, the degradation kinetics of residual and aqueous oils is determined through biodegradation tests. The studies show that dominant microorganisms have been formed in the soils after long-term sewage irrigation. The microorganisms mainly include bacteria, and a few of fungus and actinomycetes.After a 110-days‘ biodegradation test, the degradation rate of residual oil is 9.74%--10.63%, while the degradation rate of aqueous oil reaches 62.43 %. This indicates that the degradation rate of low-carbon aqueous oil is higher than that of highcarbon residual oil. In addition, although microbial degradation of petroleum contaminants in soils is suitable to the firstorder kinetics equation, the half-lives of aqueous oil, No. 20 heavy diesel and residual oil in the surface soils (L2-1, S1-1 and X1-1) are 1732 h, 3465 h and 17325 h, respectively.  相似文献   

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