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Laboratory study on the bioremediation of diesel oil contaminated soil from a petrol station

Mariano, Adriano Pinto; Kataoka, Ana Paula de Arruda Geraldes; Angelis, Dejanira de Franceschi de; Bonotto, Daniel Marcos
Fonte: Sociedade Brasileira de Microbiologia Publicador: Sociedade Brasileira de Microbiologia
Tipo: Artigo de Revista Científica Formato: 346-353
ENG
Relevância na Pesquisa
66.31%
O objetivo do presente estudo foi investigar possíveis métodos para aumentar a taxa de biodegradação aeróbia de hidrocarbonetos (tratamentos ex-situ). Neste trabalho, processos de biorremediação foram aplicados a um solo arenoso com alto nível de contaminação ocasionada por um vazamento de um tanque de armazenamento de óleo diesel subterrâneo em um posto de combustíveis. Experimentos em escala laboratorial (respirômetros de Bartha) foram utilizados para avaliar a biodegradação do óleo diesel. Estímulo da biodegradação foi realizado utilizando-se as técnicas de bioestímulo (adição de soluções de nitrogênio e fósforo ou surfactante Tween 80) e de bioaumento (consórcio bacteriano isolado de um sistema de landfarming). Para investigar as interações entre os fatores otimizadores, e encontrar a melhor combinação entre esses agentes, o estudo foi baseado em um delineamento experimental fatorial completo. A eficiência de biodegradação foi simultaneamente medida com dois métodos: respirométrico (produção de CO2 microbiano) e cromatografia gasosa. Testes de toxicidade aguda com Daphnia similis foram aplicados para examinar a eficiência dos processos em termos de geração de produtos menos tóxicos. Resultados mostraram que todas as estratégias de biorremediação aceleraram a biorremediação natural do solo contaminado e os melhores resultados foram obtidos quando os tratamentos tinham adição de nutrientes. Dados respirométricos indicaram uma máxima mineralização de hidrocarbonetos de 19...

Remediação de solo contaminado com hidrocarbonetos derivados de combustíveis utlizando lavagem oxidativa; Remediation of contaminated soil with hydrocarbons derived from fuels using oxidative washing

Emanuel José Nascimento Marques
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 20/07/2012 PT
Relevância na Pesquisa
66.29%
Neste trabalho foi avaliado um processo de lavagem de solo utilizando solução oxidante, visando a remediação de áreas contaminadas com hidrocarbonetos provenientes combustíveis. O processo foi denominado de lavagem oxidativa e consistiu na mistura de H2O2 com um catalisador de Fenton modificado, chamado Fentox®. A lavagem oxidativa foi aplicada em solo contaminado artificialmente com óleo diesel em laboratório, a fim de avaliar as mudanças ocorridas no perfil de distribuição dos hidrocarbonetos remanescentes no solo tratado e verificar as condições experimentais que resultassem em máxima remoção destes contaminantes. Foi possível obter remoção de 90% para alcanos totais, 69% para hidrocarbonetos policíclicos aromáticos (HPA) totais, e 86% para hidrocarbonetos totais de petróleo (HTP). O aumento na proporção entre fase líquida e fase sólida resultou em maior eficiência na remoção dos contaminantes. A lavagem do solo utilizando o agente tensoativo dodecil benzeno sulfonato de sódio (DBSS) foi outro aspecto investigado em laboratório. Verificou-se que em solo com baixa concentração inicial de HPA o uso do tensoativo não favoreceu a solubilização dos contaminantes. Além disso, a adição de tensoativo durante a lavagem oxidativa do solo não contribuiu para melhorar o desempenho do processo de remediação. O processo de lavagem oxidativa juntamente com solução de tensoativo foi aplicado em solo contaminado com óleos combustíveis em uma área localizada na cidade de São Paulo...

Preliminary identification of the bioremediation limiting factors of a clay bearing soil contaminated with crude oil

Rizzo,Andréa C. L.; Cunha,Claudia D. da; Santos,Ronaldo L. C.; Santos,Renata M.; Magalhães,Hugo M.; Leite,Selma G. F.; Soriano,Adriana U.
Fonte: Sociedade Brasileira de Química Publicador: Sociedade Brasileira de Química
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2008 EN
Relevância na Pesquisa
56.34%
Bioremediation is an attractive alternative to treat soils contaminated with petroleum hydrocarbons. However, the effectiveness of biodegradation process can be limited by both contaminant characteristics and its bioavailability in soil. This work aims at establishing a preliminary procedure to identify the main factor (hydrocarbon recalcitrance or its bioavailability) that impairs the biodegradation, possibly resulting in low remediation efficiencies. Tests in soil microcosms were carried out applying biostimulation and bioaugmentation techniques. Similar experiments were conducted using liquid medium containing crude oil and microorganisms, both of them extracted from a weathered contaminated soil sample, nutrients and microbial inoculum constituted of Rhodoturula glutinis and Nocardia nova. After 30 days, highest microcosms biodegradation levels (98.8%) were obtained with bioaugmentation in liquid medium, pointing out that the main problem of petroleum hydrocarbon utilization by microorganisms was associated to its availability and not only to the intrinsic recalcitrancy of remaining pollutants.

Production of CO2 in crude oil bioremediation in clay soil

Baptista,Sandro José; Cammarota,Magali Christe; Freire,Denize Dias de Carvalho
Fonte: Instituto de Tecnologia do Paraná - Tecpar Publicador: Instituto de Tecnologia do Paraná - Tecpar
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/06/2005 EN
Relevância na Pesquisa
56.33%
The aim of the present work was to evaluate the biodegradation of petroleum hydrocarbons in clay soil a 45-days experiment. The experiment was conducted using an aerobic fixed bed reactor, containing 300g of contaminated soil at room temperature with an air rate of 6 L/h. The growth medium was supplemented with 2.5% (w/w) (NH4)2SO4 and 0.035% (w/w) KH2PO4. Biodegradation of the crude oil in the contaminated clay soil was monitored by measuring CO2 production and removal of organic matter (OM), oil and grease (OandG), and total petroleum hydrocarbons (TPH), measured before and after the 45-days experiment, together with total heterotrophic and hydrocarbon-degrading bacterial count. The best removals of OM (50%), OandG (37%) and TPH (45%) were obtained in the bioreactors in which the highest CO2 production was achieved.

Comparison of biostimulation and bioaugmentation techniques for the remediation of used motor oil contaminated soil

Abdulsalam,Surajudeen; Omale,Adaji Benjamin
Fonte: Instituto de Tecnologia do Paraná - Tecpar Publicador: Instituto de Tecnologia do Paraná - Tecpar
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/06/2009 EN
Relevância na Pesquisa
76.25%
This study was carried out on the bioremediation of used motor oil contaminated soil artificially contaminated to a pollutant level of 40,000ppm using biostimulation and bioaugmentation remediation techniques for 42 days. Four treatment options were investigated in wooden microcosms: Control (T1), water amended (T2), biostimulation (T3) and hybrid of biostimulation and bioaugmentation (T4). The effectiveness of bioremediation processes were monitored using the total petroleum hydrocarbon removal (TPH) and total bacterial count (TBC). T3 had the highest TPH removal rate (69.2±0.05%), followed by T4 (65.2±0.25%) and T2 (58.4±0.5%); the control (T1) had the lowest TPH removal rate (43.2±1.5%). TBC revealed that bioremediation actually took place; T4 had the highest maximum bacterial growth of 9.6E+07CFU/g, followed by T3 (7.2E+07CFU/g), T2 (1.7E+05CFU/g) and T1 (1.65E+05CFU/g). In addition, T3 had the highest metal removal rate (2.172%) and T4 had the lowest metal removal rate (0.203%).

Laboratory study on the bioremediation of diesel oil contaminated soil from a petrol station

Mariano,Adriano Pinto; Kataoka,Ana Paula de Arruda Geraldes; Angelis,Dejanira de Franceschi de; Bonotto,Daniel Marcos
Fonte: Sociedade Brasileira de Microbiologia Publicador: Sociedade Brasileira de Microbiologia
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/06/2007 EN
Relevância na Pesquisa
66.31%
The purpose of the present study was to investigate possible methods to enhance the rate of aerobic biodegradation of hydrocarbons (ex-situ treatments). In this work, the bioremediation processes were applied to a sandy soil with a high level of contamination originated from the leakage of a diesel oil underground storage tank at a petrol station. Laboratory scale experiments (Bartha biometer flasks) were used to evaluate the biodegradation of the diesel oil. Enhancement of biodegradation was carried out through biostimulation (addition of nitrogen and phosphorus solutions or Tween 80 surfactant) and bioaugmentation (bacterial consortium isolated from a landfarming system). To investigate interactions between optimizing factors, and to find the right combination of these agents, the study was based on full factorial experimental design. Efficiency of biodegradation was simultaneously measured by two methods: respirometric (microbial CO2 production) and gas chromatography. Acute toxicity tests with Daphnia similis were applied for examination of the efficiency of the processes in terms of the generation of less toxic products. Results showed that all bioremediation strategies enhanced the natural bioremediation of the contaminated soil and the best results were obtained when treatments had nutritional amendment. Respirometric data indicated a maximum hydrocarbon mineralization of 19.8%...

Characterization of pyrene utilizing Bacillus spp. from crude oil contaminated soil

Khanna,Purnima; Goyal,Dinesh; Khanna,Sunil
Fonte: Sociedade Brasileira de Microbiologia Publicador: Sociedade Brasileira de Microbiologia
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/06/2012 EN
Relevância na Pesquisa
96.4%
Pyrene, a high molecular weight polycyclic aromatic hydrocarbon (PAH), is a priority pollutant present in soil contaminated with crude oil, coal-tar and complex PAHs. Bacterial consortium CON-3 developed from crude oil contaminated soil of Patiala, Punjab (India) cometabolized 50 µg ml-1 pyrene in the presence of glucose (0.5 %; w/v) at 30 °C, as determined by reverse-phase high performance liquid chromatography (HPLC). Bacillus sp. PK-12, Bacillus sp. PK-13 and Bacillus sp. PK-14 from CON-3, identified by 16S rRNA gene sequence analysis, were able to cometabolize 64 %, 55 % and 53 % of pyrene in 35 days, respectively. With the increase in glucose concentration to 1.0 % (w/v) in growth medium isolates PK-12, PK-13 and PK-14 showed 19 - 46 % uptake of 50 µg ml-1 pyrene in 4 days, respectively. Uptake of pyrene was correlated with growth and biosurfactant activity, which is suggestive of the potential role of members of Bacillus genera in pyrene mobilization and its uptake.

In situ biosurfactant production and hydrocarbon removal by Pseudomonas putida CB-100 in bioaugmented and biostimulated oil-contaminated soil

Ángeles,Martínez-Toledo; Refugio,Rodríguez-Vázquez
Fonte: Sociedade Brasileira de Microbiologia Publicador: Sociedade Brasileira de Microbiologia
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2013 EN
Relevância na Pesquisa
66.24%
In situ biosurfactant (rhamnolipid) production by Pseudomonas putida CB-100 was achieved during a bioaugmented and biostimulated treatment to remove hydrocarbons from aged contaminated soil from oil well drilling operations. Rhamnolipid production and contaminant removal were determined for several treatments of irradiated and non-irradiated soils: nutrient addition (nitrogen and phosphorus), P. putida addition, and addition of both (P. putida and nutrients). The results were compared against a control treatment that consisted of adding only sterilized water to the soils. In treatment with native microorganisms (non-irradiated soils) supplemented with P. putida, the removal of total petroleum hydrocarbons (TPH) was 40.6%, the rhamnolipid production was 1.54 mg/kg, and a surface tension of 64 mN/m was observed as well as a negative correlation (R = -0.54; p < 0.019) between TPH concentration (mg/kg) and surface tension (mN/m), When both bacteria and nutrients were involved, TPH levels were lowered to 33.7%, and biosurfactant production and surface tension were 2.03 mg/kg and 67.3 mN/m, respectively. In irradiated soil treated with P. putida, TPH removal was 24.5% with rhamnolipid generation of 1.79 mg/kg and 65.6 mN/m of surface tension...

Bioremediation (Natural Attenuation and Biostimulation) of Diesel-Oil-Contaminated Soil in an Alpine Glacier Skiing Area

Margesin, R.; Schinner, F.
Fonte: American Society for Microbiology Publicador: American Society for Microbiology
Tipo: Artigo de Revista Científica
Publicado em /07/2001 EN
Relevância na Pesquisa
56.24%
We investigated the feasibility of bioremediation as a treatment option for a chronically diesel-oil-polluted soil in an alpine glacier area at an altitude of 2,875 m above sea level. To examine the efficiencies of natural attenuation and biostimulation, we used field-incubated lysimeters (mesocosms) with unfertilized and fertilized (N-P-K) soil. For three summer seasons (July 1997 to September 1999), we monitored changes in hydrocarbon concentrations in soil and soil leachate and the accompanying changes in soil microbial counts and activity. A significant reduction in the diesel oil level could be achieved. At the end of the third summer season (after 780 days), the initial level of contamination (2,612 ± 70 μg of hydrocarbons g [dry weight] of soil−1) was reduced by (50 ± 4)% and (70 ± 2)% in the unfertilized and fertilized soil, respectively. Nonetheless, the residual levels of contamination (1,296 ± 110 and 774 ± 52 μg of hydrocarbons g [dry weight] of soil−1 in the unfertilized and fertilized soil, respectively) were still high. Most of the hydrocarbon loss occurred during the first summer season ([42 ± 6]% loss) in the fertilized soil and during the second summer season ([41 ± 4]% loss) in the unfertilized soil. In the fertilized soil...

Non-destructive Analysis of Oil-Contaminated Soil Core Samples by X-ray Computed Tomography and Low-Field Nuclear Magnetic Resonance Relaxometry: a Case Study

Nakashima, Yoshito; Mitsuhata, Yuji; Nishiwaki, Junko; Kawabe, Yoshishige; Utsuzawa, Shin; Jinguuji, Motoharu
Fonte: Springer Netherlands Publicador: Springer Netherlands
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
56.4%
Non-destructive measurements of contaminated soil core samples are desirable prior to destructive measurements because they allow obtaining gross information from the core samples without touching harmful chemical species. Medical X-ray computed tomography (CT) and time-domain low-field nuclear magnetic resonance (NMR) relaxometry were applied to non-destructive measurements of sandy soil core samples from a real site contaminated with heavy oil. The medical CT visualized the spatial distribution of the bulk density averaged over the voxel of 0.31 × 0.31 × 2 mm3. The obtained CT images clearly showed an increase in the bulk density with increasing depth. Coupled analysis with in situ time-domain reflectometry logging suggests that this increase is derived from an increase in the water volume fraction of soils with depth (i.e., unsaturated to saturated transition). This was confirmed by supplementary analysis using high-resolution micro-focus X-ray CT at a resolution of ∼10 μm, which directly imaged the increase in pore water with depth. NMR transverse relaxation waveforms of protons were acquired non-destructively at 2.7 MHz by the Carr–Purcell–Meiboom–Gill (CPMG) pulse sequence. The nature of viscous petroleum molecules having short transverse relaxation times (T2) compared to water molecules enabled us to distinguish the water-saturated portion from the oil-contaminated portion in the core sample using an M0–T2 plot...

Complete Genome Sequence of Raoultella ornithinolytica Strain B6, a 2,3-Butanediol-Producing Bacterium Isolated from Oil-Contaminated Soil

Shin, Sang Heum; Um, Youngsoon; Beak, Jeong Hun; Kim, Sehwan; Lee, Soojin; Oh, Min-Kyu; Kim, Young-Rok; Lee, Jinwon; Yang, Kap-Seok
Fonte: American Society for Microbiology Publicador: American Society for Microbiology
Tipo: Artigo de Revista Científica
Publicado em 27/06/2013 EN
Relevância na Pesquisa
66.14%
Here we report the full genome sequence of Raoultella ornithinolytica strain B6, a Gram-negative aerobic bacillus belonging to the family Enterobacteriaceae. This 2,3-butanediol-producing bacterium was isolated from oil-contaminated soil on Backwoon Mountain in South Korea. Strain B6 contains 5,398,151 bp with 4,909 protein-coding genes, 104 structural RNAs, and 55.88% G+C content.

Characterization of pyrene utilizing Bacillus spp. from crude oil contaminated soil

Khanna, Purnima; Goyal, Dinesh; Khanna, Sunil
Fonte: Sociedade Brasileira de Microbiologia Publicador: Sociedade Brasileira de Microbiologia
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
66.3%
Pyrene, a high molecular weight polycyclic aromatic hydrocarbon (PAH), is a priority pollutant present in soil contaminated with crude oil, coal-tar and complex PAHs. Bacterial consortium CON-3 developed from crude oil contaminated soil of Patiala, Punjab (India) cometabolized 50 μg ml-1 pyrene in the presence of glucose (0.5 %; w/v) at 30 °C, as determined by reverse-phase high performance liquid chromatography (HPLC). Bacillus sp. PK-12, Bacillus sp. PK-13 and Bacillus sp. PK-14 from CON-3, identified by 16S rRNA gene sequence analysis, were able to cometabolize 64 %, 55 % and 53 % of pyrene in 35 days, respectively. With the increase in glucose concentration to 1.0 % (w/v) in growth medium isolates PK-12, PK-13 and PK-14 showed 19 - 46 % uptake of 50 μg ml-1 pyrene in 4 days, respectively. Uptake of pyrene was correlated with growth and biosurfactant activity, which is suggestive of the potential role of members of Bacillus genera in pyrene mobilization and its uptake.

Potential Use of Mushrooms and Spent Substrate in decontamination of Oil Contaminated Soil

Anchang, Yongabi; David, Lewis
Fonte: Universidade de Adelaide Publicador: Universidade de Adelaide
Tipo: Conference paper
Publicado em //2010
Relevância na Pesquisa
66.58%
Preliminary studies on the enhancement of biodegradation of used lubricating oil, a petroleum bye product, in soil amended with dried powdered Pleurotus tuberregium (PT) and Pleurotus ostreatus fruits (PO), Powdered sclerotium of pleurotus tuberregium (SCPT) and spent substrate of Pleurotus ostreatus (SPO) was carried out in randomized pots of 400g of soil. The objective was to study the effect of mushroom and spent substrate as a biocatalysts in the clean up of soil contaminated with petroleum products in the tropics. An absorption spectrophotometer with a wavelength of 640nm was used to analyse the oil content of the contaminated soil after extraction with n-hexane. After seven weeks, the amount of lubricating oil in the untreated soil (not amended with the mushroom fruits, sclerotium and spent substrate) dropped from 960mg/g to 282mg/g. On application of varying quantities up to 60g each of PT, PO, SCPT, SPO, into the lubricating oil contaminated soil and left for seven weeks, the residual lube oil concentration dropped drastically from 960mg/g to 0.05mg/g, 0.5mg/g, 1mg/g and 2.7mg/g respectively. PT supported faster break down of the oil than PO, SCPT and SPO. Corrobaration between higher crude protein and higher biodegradation efficiency was noted. The PH of untreated soil slowly dropped from 8.15 to 7.77 in the 7th week while PH of oil contaminated soil was 7.0 for the same period with increased microbial diversity and population. Results suggest that mushroom and spent substrate could be employed as cheap clean up agents of oil contaminated soil in the tropics.; http://www.chemeca2010.com/abstract/63.asp; Yongabi Anchang & Lewis David

The surveying of soil and groundwater pollution in a petroleum refinery and the potential of bioremediation for oil decontamination

Zargar, M.; Sarrafzadeh, M.H.; Taheri, B.; Tavakoli, O.
Fonte: Taylor & Francis Publicador: Taylor & Francis
Tipo: Artigo de Revista Científica
Publicado em //2013 EN
Relevância na Pesquisa
66.47%
Soil contamination with crude oil is an important worldwide issue and the remediation of oil contaminated soils, sediments and groundwater is a major environmental challenge. In the target area of this survey, which is a petroleum refinery near Tehran, soil and groundwater pollution, and its source, contaminated area, and distribution of pollution were studied by means of different measurements. Oil content and volatile organic compounds were measured to determine soil and groundwater contamination. The investigations showed that the contamination of soil which is mainly silt and clay has reached to the groundwater which is around 20 m underground and formed an oily layer mainly containing gasoline, kerosene, and gas oil with different thicknesses in the whole area. The free oil existing over the groundwater table could be removed by physical ways such as pump and treat method but decontamination of soil is more complex. Due to long-lasting contamination of the field, the existence of accumulated indigenous microorganisms and the probable ability of them to effectively biodegrade pollutants by man-assisted interventions are expected. In this survey in order to clarify the contamination problem, some experiments have been done on the region soil and groundwater. Besides...

Switchable Surfactants for Soil Remediation

CESCHIA, ELIZE
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado
EN; EN
Relevância na Pesquisa
56.54%
Soil remediation requires technologies to restore contaminated soil to a state that is environmentally acceptable. In most cases, while the soil can be remediated the contaminant itself cannot be reclaimed. Soil washing involves cleaning contaminated soil with a wash solution, generally an aqueous solution of a surfactant. It was proposed that using switchable surfactants for washing oil-contaminated soil will not only help remove the oil from soil, but also aid in the recovery of the oil contaminant from the wash mixture. Six surfactants were evaluated for their ability to wash Ottawa Sand artificially contaminated with North Sea crude oil. A water wash solution was used as a control. Two commercial surfactants, sodium dodecyl sulfate (SDS) and Triton X-100, and four switchable surfactants, N'-octyl-N,N-dimethylamidine (C8), sodium octyl 4-hydroxy-3-nitrobenzoate (SAS1), sodium 4-(octyoxy) benzoate (SAS2) and sodium laurate (SAS3) were studied. The surfactants were assessed based on their ability to remove oil from the sand and their ability to separate the crude oil from the wash mixture after CO2 treatment. Oil removal from sand was determined by gravimetric analysis. Oil content in the wash mixture was determined using Solid Phase Extraction and gravimetric analysis. It was determined that switchable surfactants are able to remove North Sea crude oil from sand as well or better than the commercial surfactants and have the added feature of oil separation and recovery from the wash mixture after CO2 treatment.; Thesis (Master...

Bioaugmentation with Petroleum-Degrading Consortia Has a Selective Growth-Promoting Impact on Crop Plants Germinated in Diesel Oil-Contaminated Soil

Graj, Weronika; Lisiecki, Piotr; Szulc, Alicja; Chrzanowski, Łukasz; Wojtera-Kwiczor, Joanna
Fonte: Springer Netherlands Publicador: Springer Netherlands
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
66.34%
Rhizoremediation is a complex type of green clean-up technology that involves both plants and the rhizosphere-associated microorganisms to decompose hazardous compounds. The success of the strategy strongly depends on plant tolerance towards the pollutant, as well as plant's interactions with the rhizospheric microbes. The microorganisms may be stimulated by the secreted root exudates, which results in an increased breakdown of contaminants in the rhizosphere. The main goal of this study was to establish a potential rhizoremediation combination for a diesel-polluted site. Inoculation of plant roots or seeds with indigenous rhizospheric populations is a common approach in the rhizoremediation. However, we introduced hydrocarbon-degrading consortia (M10, R3, and K52) that were previously isolated from crude oil-contaminated soil instead of indigenous microbes. Bioaugmentation with these petroleum degraders was applied to screen four high biomass crop species (Indian mustard, alfalfa, high erucic acid rapeseed, HEAR, and low erucic acid rapeseed, LEAR) for their tolerance towards diesel oil. At no pollution, a promoting effect of M10 bacteria could be observed on germination and root elongation of all plant species. Moreover, M10 consortiums increased the germination index at 6...

Bioremediation of petroleum hydrocarbons from crude oil-contaminated soil with the earthworm: Hyperiodrilus africanus

Ekperusi, O. A.; Aigbodion, F. I.
Fonte: Springer Berlin Heidelberg Publicador: Springer Berlin Heidelberg
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
56.4%
A study on the bioremediation potentials of the earthworm Hyperiodrilusafricanus (Beddard) in soil contaminated with crude oil was investigated. Dried and sieved soils were contaminated with 5 ml each of crude oil with replicates and inoculated with earthworms and monitored daily for 12 weeks. Physicochemical parameters such as pH, total organic carbon, sulfate, nitrate, phosphate, sodium, potassium, calcium and magnesium were determined using standard procedures. Total petroleum hydrocarbon (TPH) was determined using atomic absorption spectrophotometer (AAS), while BTEX constituents and earthworms tissues were analyzed using Gas Chromatography with Flame Ionization Detector (GC-FID). The results showed that the earthworm significantly enhanced the physicochemical parameters of the contaminated soil resulting in a decrease of the total organic carbon (56.64 %), sulfate (57.66 %), nitrate (57.69 %), phosphate (57.73 %), sodium (57.69 %), potassium (57.68 %), calcium (57.69 %) and magnesium (57.68 %) except pH (3.90 %) that slightly increased. There was a significant decrease in the TPH (84.99 %), benzene (91.65 %), toluene (100.00 %), ethylbenzene (100.00 %) and xylene (100.00 %). Analyses of the tissues of the earthworm at the end of the experiment showed that the earthworms bioaccumulated/biodegraded 57.35/27.64 % TPH...

Assessment of in situ bioremediation of oil contaminated soil and groundwater in a petroleum refinery: a laboratory soil column study

Zargar, M.; Sarrafzadeh, M.H.; Taheri, B.; Keshavarz, A.
Fonte: Taylor & Francis Publicador: Taylor & Francis
Tipo: Artigo de Revista Científica
Publicado em //2014 EN
Relevância na Pesquisa
76.35%
Precipitation and seasonal water level fluctuations mostly add to the problem of soil and groundwater contamination and lead to pollution of capillary fringe layer and exacerbation of groundwater contamination. At the Tehran Oil Refining Company (TORC), with critical problem of soil and groundwater pollution, finding a suitable remediation method has been a big concern. As bioremediation is one of the most economically and technically attractive decontamination methods, it was chosen for preliminary study to solve this problem. For simulation of the region, soil column treatment method by using oil habituated indigenous microorganisms of the area was selected. The main purpose was assessing the suitability of bioremediation method in the target area for treatment of capillary fringe layer. Two columns (one as treatment column and the other as a control) were designed and the variation of different parameters including dissolved oxygen (DO), pH, the number of viable and active microorganisms (CFU/mL), and biodegradation rate during 30 working days were recorded. The experiments showed that a major part of degrading microorganisms were facultative anaerobic. pH was not an inhibiting factor and the number of active microorganisms was increasing during aeration time. The results of solvent extraction method also revealed that during 30 days...

Tropical bacteria isolated from oil-contaminated mangrove soil: bioremediation by natural attenuation and bioaugmentation

Ruiz-Marín,A.; Zavala-Loria,J.C.; Canedo-López,Y.; Cordova-Quiroz,A.V.
Fonte: UAM, Unidad Iztapalapa, División de Ciencias Básicas e Ingeniería Publicador: UAM, Unidad Iztapalapa, División de Ciencias Básicas e Ingeniería
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2013 EN
Relevância na Pesquisa
66.35%
The biodegradation of DRO compounds was evaluated by the processes of natural attenuation and bioaugmentation in mangrove soil. Prior to the experimente, a consortium of bacteria capable of degrading hydrocarbons was isolated and identified: Pseudomonas aeruginosa, P. luteola, Sphingomonas paucimobiiis and P. fluorescens. For natural attenuation, mangrove oil contaminated soil was placed in horizontal tubular reactors with air supply and no addition of bacteria. While for bioaugmentation three initial inocula from bacterial consortium (0,02, 0.04 and 0.06 g L-1 biomass dry weight) were added to the mangrove soil, maintaining aeration and moisture (30-). The samples were collected every 30 days during 3 months and the oil content was analyzed with a gas chromatograph (GC). The degradation of diesel oil range (40.3%) was higher with an inocula size of 0.06 g L-1, where C12, C18 and C26 were the most susceptible to degradation, while in trie process of natural attenuation only 4.51% was removed, suggesting that the low nutrient content in the mangrove soil and bacteria number could limit; the hydrocarbon degradation. Therefore it is possible to increase the degradation through bioaugmentation in a system as the mangrove soil.

Estimation of soil petrophysical parameters from resistivity data: Application to oil-contaminated site characterization

Shevnin,Vladimir; Delgado Rodríguez,Omar; Mousatov,Aleksandr; Flores Hernández,David; Zegarra Martínez,Héctor; Ryjov,Albert
Fonte: Instituto de Geofísica, UNAM Publicador: Instituto de Geofísica, UNAM
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/09/2006 EN
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Vertical Electrical Sounding (VES) method, known from 1912, has changed greatly during the last 10 years, into a new technology named Resistivity Imaging (RI) with 2D data interpretation. Another possible development for VES method is estimating petrophysical parameters (PP) from RI data, using the relationship between electrical resistivity and PP. In order to reach this purpose, the theory of the forward and inverse problem that relates the electrical resistivity with PP was developed. Each field survey should include a VES (RI) survey, groundwater resistivity measurements in order to determine the groundwater salinity, and collecting some representative soil samples in the study site for resistivity measurements as function of pore water salinity in laboratory, creating a soil petrophysical model of the site. This technology can be used for the characterization of uncontaminated and oil contaminated sites. For the case of contaminated site PP values determined in laboratory, groundwater salinity and RI data help to define the petrophysical boundary between contaminated and uncontaminated soil, and consequently, to obtain the contamination plume. In this work, the results of the application of this technology in some hydrocarbon contaminated sites in Mexico are presented.