Effects of oil shale waste disposal on soil and water quality: hydrogeochemical aspects

Abstract

Environmental pollution from solid waste landfillings (SWLs) is of major concern to both the environmentalists and to individual citizens. The necessity for studying on contaminant generation and control is becoming more urgent in view of the risks associated with such sites.

An oil shale tailing at Maoming, South China, was chosen as our study case. Soil samples, water samples and oil shale tailings were collected from the site and analyzed for their compositions. The analytical results revealed that the soil and groundwater were contaminated to various degrees by several chemicals or pollutants from the oil shale tailings. The major environmental problems associated with the site were acidification of soil and groundwater, high content of heavy metals and sulfate in soil and groundwater and organic contamination of soil, in particular, finding of carcinogenous benzo[a] pyrene other PAHs.

Statistical and geochemical methods were applied to reveal the sources of contaminants. Soil and groundwater contamination were correlated obviously with the oil shale waste disposal. The nearer the sampling sites to the tailing, the heavier the soil and groundwater were contaminated. The different water samples composition had same chemical characteristics. The soil and water samples were analyzed for 16 PAHs (USEPA priority pollutants). It indicated that PAHs were retained mostly in the soil, which consisted of mainly naphthalene, fluorene, phenanthrene and anthracene. Analysis for PAHs source revealed that they were also from the oil shale tailing.     

Biodegradation of a dilute waste oil emulsion applied to soil

Summary The use of land treatment for disposal of a dilute waste oil emulsion generated by an aluminum rolling industry was investigated. Major components of the waste, identified by gas chromatography and mass spectrometry, were linear and branched (C₁₂–C₂₅) and fatty acid emulsifiers (primarily, isomers of oleic acid). Hexadecane and pristane were readily biodegraded in vitro when added to soil collected from the waste disposal site. Hydrocarbons and fatty acids extracted from the waste were similarly, biodegraded, however, the rate of decomposition may have depended on the history of waste applications to soil collected from the land treatment site. The apparent half-life of resolvable waste hydrocarbons and fatty acids was 9.5 days in soil which had received waste applications averaging 25.4l m^–2 wk^–1. In contrast, soil receiving either 50.8l m^–2 wk^–1 or no waste application during summer 1987 apparent exhibited half-lives of 28.1 and 60.3 days, respectively. Waste components were restricted to the upper 48 cm of the soil cores collected from the disposal site. Core samples also provided evidence for biodegradation of hydrocarbons and fatty acids as well as an accumulation of other compounds not readily resolvable by gas chromatographyPublished with the approval of the Director of the West Virginia University Agriculture and Forestry Experiment Station as Scientific Article # 2122.     

Biodegradation of phenanthrene by Pseudomonas sp. BZ-3, isolated from crude oil contaminated soil

A phenanthrene (PHE) degrading bacterium strain BZ-3 was isolated from the crude oil contaminated soil in Binzhou, China. The isolate was identified as Pseudomonas sp. BZ-3 on the basis of 16S rRNA gene sequence. Various experiments were conducted to investigate the effect of pH, salinity and PHE concentration on the degradation efficiency of PHE. The degradation efficiency and degradation metabolites of PHE were detected by using GC–MS and HPLC-MS analyses. The strain BZ-3 could degrade 75% of PHE at an initial concentration of 50 mg/L under 20 g/L salinity in 7 days. PHE degradation kinetics was estimated in a first-order degradation rate model and the rate coefficient was calculated as 0.108 d⁻¹. On the basis of the identified degradation metabolites, the strain BZ-3 could degrade PHE in the salicylate metabolic pathway. In a mixture system consisting of PHE and other PAHs including naphthalene (NA), anthracene (ANTH), and pyrene (PYR), the strain BZ-3 showed an efficiently degradation capability. Further study showed that the strain BZ-3 could also use NA, ANTH, PYR, xylene, 1-hydroxy-2-naphthoic acid, and hexane as the sole carbon and energy source, but did not grow on nitrobenzene-containing medium.     

Biodegradation of polycyclic aromatic hydrocarbons in soil around Mathura oil refinery,India

Six polycyclic aromatic hydrocarbons [naphthalene, anthracene, phenanthrene, pyrene, chrysene and benzo(a)-pyrene] were detected in soil receiving effluents from an oil refinery. Biodegradation studies revealed a time-dependent disappearance of these polycyclic aromatic hydrocarbons when they were added to soil samples: naphthalene disappeared completely in 60 days, whereas phenanthrene, anthracene, pyrene, chrysene and benzo(a)pyrene decreased by 87%, 34%, 21%, 5% and 40%, respectively, in 120 days.B.T. Ashok and J. Musarrat were and S. Saxena is with the Interdisciplinary Biotechnology Unit, A.M.U., Aligarh-202002, Uttar Pradesh, India. K.P. Singh is with the Environmental Chemistry Section, Industrial Toxicology Research Centre, M.G. Road, Lucknow-226001, Uttar Pradesh, India. B.T. Ashok is now with the Department of Biochemistry, J.N. Medical College, A.M.U., Aligarh-202002, Uttar Pradesh, India. J. Musarrat is now with the Department of Radiology and Blochemistry Program. The Ohio State University, Columbus, OH 43210, USA.     

Biodegradation of petroleum industry oily-sludge using Jordanian oil refinery contaminated soil

The main objective of this study was to evaluate the effect of oily sludge concentration on its biodegradability in soil. Oily sludge was collected and applied to microcosms at full-, half-, or quarter-strength concentrations equivalent to 44.2, 22.2, and 11.1 g kg^?1 soil, respectively, of total petroleum hydrocarbons (TPH) contained in oily sludge. The biodegradability of oily sludge was evaluated by measuring CO₂ evolution and by measuring removal of TPH as well as its main composing fractions; namely; alkanes, aromatics, NSO-compounds, and asphaltenes. The collected soil contained 3.63 × 10⁶ cfu g^?1 soil of hydrocarbon-degrading bacteria, which is satisfactory to drive successful biodegradation of hydrocarbons in soil. These numbers increased significantly with oily sludge addition at a rate proportional to the added TPH reaching 3.35 × 10⁷ cfu g^?1 soil in the half-strength treatment. TPH mineralization rate followed the same pattern. However, TPH-mineralization efficiency was the greatest in quarter-strength treatment at 18.3%. TPH-removal efficiency was also highest in quarter-strength treatment at 30.9%. Nutrients addition caused mineralization inhibition. Since nutrients were added as a ratio of the added carbon, inhibition was the greatest with the highest TPH treatment. While alkanes were degraded, aromatics and asphaltenes were not, and NSO-compounds were enriched. Although SDS was completely biodegradable in soil, its addition promoted mineralization and removal of TPH from soil.     

Mycoremediation of crude oil contaminated soil by specific fungi isolated from Dhahran in Saudi Arabia

Crude oil biodegrading microorganism considers the key role for environmental preserving. In this investigation, crude oil biodegrading fungal strains have been isolated in polluted soil of crude-oil at khurais oil ground in Kingdom of Saudi Arabia. Among of 22 fungal isolates, only three isolates reflected potential capability for oil degradation. These isolates were identified and submitted to GenBank as (A1) Aspergillus polyporicola (MT448790), (A2) Aspergillus spelaeus (MT448791) and (A3) Aspergillus niger (MT459302) through internal-transcribed spacer-regions (ITS1&ITS2) for sequencing in molecular marker. Comparing with controls, strain (A1) Aspergillus niger was superior for biodegradation ability (58%) comparing with Aspergillus polyporicola and Aspergillus spelaeus degrading were showed 47 and 51% respectively. Employed CO₂ evolution as indicator for petroleum oil biodegradation by the fungal isolates reflected that, Aspergillus niger emission highest CO2 (28.6%) comparing with Aspergillus spelaeus and Aspergillus polyporicola which showed 13% and 12.4% respectively. capability of Aspergillus sp. to tolerate and adapted oil pollutants with successful growth rate on them, indicated that it can be employed as mycoremediation agent for recovering restoring ecosystem when contaminated by crude oil.     

Biodegradation of aliphatic hydrocarbon by indigenous fungi isolated from used motor oil contaminated sites

Eighteen indigenous fungal isolates has been successfully isolated from samples of used motor oil, top five centimetres of soil and drainage water contaminated with used motor oil. All of the pure fungal isolates obtained were identified, characterized and subjected to preliminary screening by evaluating the average growth rate of each fungal isolates on minimal media containing 1% (v/v) used motor oil. Trichoderma asperellum strain TUB F-1067 (SA4), Trichoderma asperellum strain Tr48 (SA5), Trichoderma asperellum strain TUB F-756 (SA6), Penicillium species (P1), and Aspergillus species (P9) were further selected for their hydrocarbon biodegradation potential. Among these five fungal isolates selected, P1 strain presented a significant degree of degradation by degrading almost all of the n-alkanes (n-C-₁₅ to n-C-₂₃ range) present in the used motor oil, thus of greater potential in degrading the aliphatic hydrocarbon compounds of used motor oil. The authors would like to certify that the work have not been sent/considered to be published in other journals.     

Biodegradation study by Pseudomonas sp. of flexible polyurethane foams derived from castor oil

The synthesis and biodegradation of polyurethane foams obtained from environmentally benign processes were studied.Flexible polyurethane foams based on castor oil modified with maleic anhydride (MACO) were synthesized. The synthesis involved a single-stage process by mixing castor oil/MACO (weight ratios 75:25 and 25:75) and 2-4 toluene diisocyanate (TDI) in stoichiometric amount of OH:NCO. The biodegradability studies with cultures of a Pseudomonas sp. strain (DBFIQ-P36) involved incubation periods of 2 months at 37 °C. Polymers were characterized before and after biodegradation by Fourier Transform Infrared Spectroscopy (FT-IR), INSTRON mechanical tester, and Scanning Electron Microscopy (SEM). The results showed that the addition of MACO produces a considerable increase in the rate of degradation and an important change in the chemical and morphological structures. This is due to the presence of ester groups that are vulnerable to chemical hydrolysis and enzymatic attack. The eco-toxicity after the biodegradation was evaluated. Toxic compounds such as primary amines were identified by Gas Chromatography–Mass Spectrometry (GC–MS) in combination with Nuclear Magnetic Resonance (NMR) as degradation products.     

Biodegradation of polycyclic aromatic hydrocarbons (PAHs) by Cladosporium sphaerospermum isolated from an aged PAH contaminated soil

The ability of a Deuteromycete fungus, Cladosporium sphaerospermum, previously isolated from soil of an aged gas manufacturing plant, to degrade polycyclic aromatic hydrocarbons was investigated. This strain was able to degrade PAHs in non-sterile soils (average 23%), including high molecular weight PAHs, after 4 weeks of incubation. In a microcosm experiment, PAH depletion was clearly correlated to fungal establishment. In liquid culture, this strain degraded rapidly benzo(a)pyrene during its early exponential phase of growth (18% after 4 days of incubation). Among extracellular ligninolytic enzyme activities tested, only laccase activity was detected in liquid culture in the absence or in presence of benzo(a)pyrene. C. sphaerospermum might be a potential candidate for an effective bioremediation of aged PAH-contaminated soils.     

Earthworm survival in oil contaminated soil

Earthworms are an important component of the soil biota and their response to oil pollution needs to be better understood. Laboratory investigations were undertaken to determine the concentrations of crude oil in soil that leads to death of Lumbricus terrestris and Eisenia fetida and to determine the propensity of L. terrestris to move away from contaminated soil. Clemville sandy clay loam was amended to contain maximum oil contents of 1.5 – 2.5% depending on the particular experiment. Additionally, the ability of L. terrestristo survive in bioremediated oil-contaminated soil was evaluated. An oil content of 0.5% was not harmful to survival of earthworms for 7 d but an oil concentration of 1.5% reduced survival to less than 40%. Bioremediated soil containing 1.2% oil did not reduce survival of L. terrestrisduring 10 d. Survival of L. terrestrisin unweathered oil was improved when free movement between contaminated and uncontaminated soil was possible. Casts of earthworms exposed to oil-containing soil contained 0.2% total petroleum hydrocarbons. An allowable regulatory level of 1% oil contamination in soil may not allow for survival of earthworms.     

Hydrocarbon bioremediation of a mineral-base contaminated waste from crude oil extraction by indigenous bacteria

The susceptibility to bioremediation of the hydrocarbons contained in a waste from crude oil extraction was examined. Laboratory scale batch reactors were inoculated with indigenous bacteria and biodegradation was followed for 45 days. The total hydrocarbon content was reduced to 70% of its initial value at the end of the experiments. Saturated and aromatic hydrocarbons were the most readily degraded fractions with, respectively, 70% and 60% of the fraction remaining at the end of the experiment. A minor degradation was observed in the resins fraction (20%), whereas the asphaltenes fraction remained almost constant.The substrate preferences of the natural population towards various fractions of the crude oil were determined by both the length of the lag phase and the slope of the exponential growth in a mineral salt-base medium containing either of the different hydrocarbon fraction as the sole source of carbon. The highest consumption rate for every fraction during the time course experiments was in agreement with the shortest lag phase and the greatest exponential growth slope in the corresponding selective media, indicating changes in the population composition.     

Biodegradation and ecotoxicity of soil contaminated by pentachlorophenol applying bioaugmentation and addition of sorbents

Biodegradation of pentachlorophenol (PCP) in soil by autochthonous microorganisms and in soil bioaugmented by the bacterial strain Comamonas testosteroni CCM 7530 was studied. Subsequent addition of organomineral complex (OMC) or lignite as possible sorbents for PCP immobilization has been investigated as well. The OMC was prepared from humic acids (HAs) isolated from lignite by binding them onto zeolite. Biodegradation of PCP and number of colony forming units (CFUs) were determined in the three types of soil, Chernozem, Fluvisol, and Regosol, freshly spiked with PCP and amended separately with tested sorbents. The enhancing effect of sorbent addition and bioaugmentation on PCP biodegradation depended mainly on the soil type and the initial PCP concentration. Microbial activity resulted in biotransformation of PCP into certain toxic substances, probably lower chlorinated phenols that are more soluble than PCP, and therefore more toxic to present biota. Therefore, it was necessary to monitor soil ecotoxicity during biodegradation. Addition of the OMC resulted in a more significant decrease of soil toxicity in comparison with addition of lignite. Lignite and OMC appear to be good traps for PCP with potential application in remediation technology.     

中原石油污染土壤原位微生物生态修复技术的应用

利用优化原位土著微生物菌群辅以物理和化学相结合的生态修复技术, 进行了河南中原油田石油残留污染土壤的野外修复应用研究。修复结果显示, 土壤中残留石油含量平均在2 898.25 mg/kg时, 经过99 d微生物生态修复技术的实施, 土壤中石油含量降解可达99%以上, 为油田区土壤石油残留污染的修复提供了技术方法和推广应用的可行性研究。     

Biodegradation of oily sludge in Kuwait soil

Soil microorganisms were not inhibited by mixing oily sludge in soil up to 8.7% (w/w) oil (15% sludge). Adding NH ₄ ⁺ and phosphate increased microbial activity. Microbial activity was also affected by seasonal variation. Thermotolerant microorganisms were more predominant during the summer. After 29 months, 72%, 84%, and 83% of the soil was degraded in fertilized soils dosed with 2.9, 5.8 and 8.7% oil, respectively.     

石油污染土壤中苯酚降解菌ad049的鉴定及降解特性

以苯酚为唯一碳源,采用富集培养方法,从陕北靖边油田污染土壤中分离获得1株苯酚高效降解菌(ad049),对菌株进行形态观察、生理生化检验及16S rDNA序列分析,确定该菌株为红球菌(Rhodococcus)。采用摇瓶振荡培养方法,研究了接种量、pH值、温度和底物浓度对ad049生长量和苯酚降解率的影响,同时对该菌株脱氢酶和邻苯二酚双加氧酶活性进行了测定。结果表明,ad049具有较强的苯酚降解能力;在苯酚浓度1000 mg/L,温度35℃,pH值8,接种量5%的培养条件下,反应24 h后,苯酚降解率达99%以上,且整个降解过程符合零级动力学方程,速率常数k_0=41.51,相关系数R~2=0.96。通过邻苯二酚双加氧酶活性的测定,推测出该菌株降解苯酚的途径可能是以邻苯二酚1,2双加氧酶为主要途径进行邻位开环,辅以邻苯二酚2,3双加氧酶进行间位开环。     

汞污染土壤植物修复技术研究进展

汞是一种全球性污染物,汞污染土壤的修复问题,一直倍受各国科学工作者关注,土壤汞污染的植物修复技术是近年来发展起来的新兴技术.其中,汞污染土壤的植物提取技术是最有发展前途的一种汞污染土壤植物修复技术.本文对国内外有关汞污染土壤的植物修复技术进行了系统分析,对有关汞污染土壤的植物修复应用技术,如植物挥发、固化及提取等修复方法进行了评述,探讨了植物修复技术在汞污染土壤修复中的应用前景.加快对汞超积累植物的筛选和植物体对重金属耐性机制的研究,对今后开展汞污染土壤的植物修复工作具有重要的现实意义.     

Bioremediation of a polyaromatic hydrocarbon contaminated soil by native soil microbiota and bioaugmentation with isolated microbial consortia

Biodegradation of a mixture of PAHs was assessed in forest soil microcosms performed either without or with bioaugmentation using individual fungi and bacterial and a fungal consortia. Respiratory activity, metabolic intermediates and extent of PAH degradation were determined. In all microcosms the low molecular weight PAH’s naphthalene, phenanthrene and anthracene, showed a rapid initial rate of removal. However, bioaugmentation did not significantly affect the biodegradation efficiency for these compounds. Significantly slower degradation rates were demonstrated for the high molecular weight PAH’s pyrene, benz[a]anthracene and benz[a]pyrene. Bioaugmentation did not improve the rate or extent of PAH degradation, except in the case of Aspergillus sp. Respiratory activity was determined by CO₂ evolution and correlated roughly with the rate and timing of PAH removal. This indicated that the PAHs were being used as an energy source. The native microbiota responded rapidly to the addition of the PAHs and demonstrated the ability to degrade all of the PAHs added to the soil, indicating their ability to remediate PAH-contaminated soils.     

基于土壤线虫群落分析的油页岩废渣地不同植被类型恢复过程中的土壤食物网能流状况

土壤健康与生态系统功能是当前生态学研究的重要课题。土壤线虫是评价生态系统健康状况的指示生物,特别是用于评价土壤污染和恢复的过程。对广东茂名油页岩废渣场人工实施不同生态恢复改造状况下的土壤线虫属的重要值及土壤线虫反映的土壤食物网能量通道进行了分析,以通过污染地土壤食物网内的能量流动状况反映种植不同植物物种相同时间后的土壤养分与健康状况。结果表明在废渣场种植不同植物物种约8年后,乌墨林和大叶相思林下土壤线虫类群数(属)分别为54和45,重要值最高的是食细菌的棱咽属(Prismatolaimus)和拟丽突属(Acrobeloides);而红荷林和荒草地的线虫类群数分别为41和38,重要值最高的是杂食性的真矛线属(Eudorylaimus);废渣地线虫属的数量最少,仅为34个,重要值最高的是食真菌的丝尾垫刃属(Filenchus)和滑刃属(Aphelenchoides)。食物网能流分析表明:细菌能流通道比重最高的是大叶相思林和乌墨林,而真菌能流通道比重最高的是废渣地,红荷林和荒草地居中,各样地植物能流通道比重都比较小,仅为2%—10%之间。总体来讲,在有植被覆盖的生态系统,养分周转更快,特别是乌墨和大叶相思林,而无植被的废渣地,土壤养分周转速率倾向于更慢的真菌能流通道,这表明在养分条件比较差的情况下,真菌通道的食物网可能会起更大的作用。研究还说明了在油页岩废弃地恢复过程中,植物资源的输入不仅仅刺激植物能流通道,同时也会刺激细菌和真菌能流通道,植被是土壤线虫群落发展的主要驱动力。     

Biodegradation of phenanthrene by Arthrobacter polychromogenes isolated from a contaminated soil

Summary Degradation of phenanthrene by Arthrobacter polychromogenes isolated from a contaminated soil was investigated. In experiments in which [9-¹⁴C]-phenanthrene was incubated with cultures of A. polychromogenes containing 150 mg phenanthrene/l it was shown that after 26 h of incubation 47.7% of the recovered radiolabelled carbon originally present was metabolized to ¹⁴CO₂, 47.8% was recovered from the aqueous fraction, and 4.5% remained in the dichloromethane fraction. Increasing phenanthrene concentration in the culture medium resulted in improved growth and degradation rates, probably due to the higher amount of phenanthrene crystals in the medium. Shifting the temperature from 30°C to 35°C did not influence phenanthrene degradation significantly but inhibited cell division of A. polychromogenes. Medium supplementation with glucose led to stimulation of phenanthrene degradation at low amounts of glucose (0.45 g/l) whereas at higher concentrations (3 g/l) phenanthrene mineralization decreased.Professor Dr. D. Behrens dedicated to his 65th birthdayOffprint requests to: H.-J. Rehm