Biotreatment Of Soil Research Articles

Bio-treatment of soil from international airport in Ostrava

The paper deals with an examination of possible application of biodegradation in the decontamination of soil samples from international airport in Ostrava. The laboratory biodegradation tests were carried out with a pure bacterial culture of Pseudomonas putida, a pure laboratory culture of Rhodococcus sp, their mixture and a mixture prepared combining their media free of bacteria. The results of the paper imply that for biodegradation of airport pollutants is most suitable to apply a mixed bacterial culture of Pseudomonas putida and Rhodococcus sp. The results show that the biodegradation method is applicable for the pollution.

State-of-the-Art Review of the Applicability and Challenges of Microbial-Induced Calcite Precipitation (MICP) and Enzyme-Induced Calcite Precipitation (EICP) Techniques for Geotechnical and Geoenvironmental Applications

The development of alternatives to soil stabilization through mechanical and chemical stabilization has paved the way for the development of biostabilization methods. Since its development, researchers have used different bacteria species for soil treatment. Soil treatment through bioremediation techniques has been used to understand its effect on strength parameters and contaminant remediation. Using a living organism for binding the soil grains to make the soil mass dense and durable is the basic idea of soil biotreatment. Bacteria and enzymes are commonly utilized in biostabilization, which is a common method to encourage ureolysis, leading to calcite precipitation in the soil mass. Microbial-induced calcite precipitation (MICP) and enzyme-induced calcite precipitation (EICP) techniques are emerging trends in soil stabilization. Unlike conventional methods, these techniques are environmentally friendly and sustainable. This review determines the challenges, applicability, advantages, and disadvantages of MICP and EICP in soil treatment and their role in the improvement of the geotechnical and geoenvironmental properties of soil. It further elaborates on their probable mechanism in improving the soil properties in the natural and lab environments. Moreover, it looks into the effectiveness of biostabilization as a remediation of soil contamination. This review intends to present a hands-on adoptable treatment method for in situ implementation depending on specific site conditions.

Soil biotreatment effectiveness for reducing global warming potential from main polluting tillage operations in life cycle assessment phase

In order to reduce global warming potential (GWP) due to anthropogenic and natural factors in the cultivation of winter wheat and rapeseed, proved effectiveness of soil biotreatment with different composition of bio-solutions. It was reduced greenhouse gases (GHG) through life cycle impact categories from the main polluting agricultural operations on deeply lukewarm soaked soil. According to the impact diapason evaluated the main indicators such as human toxicity air (HTA), ecotoxicity water chronic (EWC), global warming potential, ecotoxicity water acute (EWA), ozone formation (OF), human toxicity water (HTW), ecotoxicity soil chronic (ESC), human toxicity soil (HTS), terrestrial eutrophication (TE), acidification (A). Assessed researches for three seasons which carried out in production experimental areas. It was appreciated in interrelated stages according to LST EN ISO 14040:2007 standard. Mass balance for one functional unit (FU) was tonne of wheat and rapeseed. SimaPro 8.05 life cycle assessment (LCA) Software was used for comparing soil biotreatment efectiveness using different bio-solutions and its mixes with control. The aim of the assessment – to prove the soil biotreatment effectiveness for reducing main life cycle indicators from tillage operations. It was identificated that phase of field operation is one of the main factor to the global impact. Disc harrowing consists approximately 26%, ploughing – 40% of all operations. Identified effectiveness of soil biotreatment, wheat and rapeseed rotation for reduction of global warming potential. Discovered reduction interdependencies of main life cycle assessement impact categories. The largest CO2 eq reducing established from primary – disc harrowing 12–15 cm and secondary - ploughing 23–25 cm soil tillage. It was fixed till approximately 15% in mixed bacterial and non-bacterial bio-solution after first soil biotreatment. Till approximately 8% CO2 eq reduction was in mixed bio–solutions after second biotreatment. The percentage highest soil biotreatment effectiveness till approximately 30% assessed after third biotreatment compared to usual technology. Soil biotreatment effectiveness in reducing green house gases (GHG) proved first year in 86%, second year in 43%, and third year in 71% of all used bio–solutions.

Bioremediation of Petroleum Hydrocarbons Contaminated Soil using Bio piles System

This study was focused on biotreatment of soil which polluted by petroleum compounds (Diesel) which caused serious environmental problems. One of the most effective and promising ways to treat diesel-contaminated soil is bioremediation. It is a choice that offers the potential to destroy harmful pollutants using biological activity.
 Four bacterial strains were isolated from diesel contaminated soil samples. The isolates were identified by the Vitek 2 system, as Sphingomonas paucimobilis, Pentoae species, Staphylococcus aureus, and Enterobacter cloacae. The potential of biological surfactant production was tested using the Sigma 703D stand-alone tensiometer showed that these isolates are biological surfactant producers. The better results of the surface tension reduction test were obtained using the mixed bacterial culture which reduced the surface tension of the medium from 66mN/m to 33.89mN/m. For further evidence of the biodegradation effect of these isolates individually and as a mixed culture, which was supported by the use of Gas-Chromatography technology confirming the occurrence of biodegradation.
 The capability of mixed bacterial culture was examined to remediate the diesel contaminated soil in bio piles system. Two pilot scale bio piles (25 kg soil each) were constructed containing soils contaminated with approximately 2140 mg/kg total petroleum hydrocarbons (TPHs). Both systems were equipped with oxygen to provide aerobic conditions, incubated at ambient temperature and weekly sampling within 35 days (during summer season). Overall 75.71 % of the total petroleum hydrocarbons were removed from the amended soil and 33.18 % of the control soil at the end of study period. The study concluded that the ex-situ bioremediation (bio piles) is a good option for treating the soil contaminated with diesel as economical and environmentally friendly.

Bioremediation of Petroleum Hydrocarbons Contaminated Soil using Bio piles System

This study was focused on biotreatment of soil which polluted by petroleum compounds (Diesel) which caused serious environmental problems. One of the most effective and promising ways to treat diesel-contaminated soil is bioremediation. It is a choice that offers the potential to destroy harmful pollutants using biological activity.
 Four bacterial strains were isolated from diesel contaminated soil samples. The isolates were identified by the Vitek 2 system, as Sphingomonas paucimobilis, Pentoae species, Staphylococcus aureus, and Enterobacter cloacae. The potential of biological surfactant production was tested using the Sigma 703D stand-alone tensiometer showed that these isolates are biological surfactant producers. The better results of the surface tension reduction test were obtained using the mixed bacterial culture which reduced the surface tension of the medium from 66mN/m to 33.89mN/m. For further evidence of the biodegradation effect of these isolates individually and as a mixed culture, which was supported by the use of Gas-Chromatography technology confirming the occurrence of biodegradation.
 The capability of mixed bacterial culture was examined to remediate the diesel contaminated soil in bio piles system. Two pilot scale bio piles (25 kg soil each) were constructed containing soils contaminated with approximately 2140 mg/kg total petroleum hydrocarbons (TPHs). Both systems were equipped with oxygen to provide aerobic conditions, incubated at ambient temperature and weekly sampling within 35 days (during summer season). Overall 75.71 % of the total petroleum hydrocarbons were removed from the amended soil and 33.18 % of the control soil at the end of study period. The study concluded that the ex-situ bioremediation (bio piles) is a good option for treating the soil contaminated with diesel as economical and environmentally friendly.

Bioremediation of Soil Contaminated with Diesel using Biopile system

ركزت هذه الدراسة على معالجة التربة الملوثة بالمركبات النفطية (الديزل) و التي تسببت في مشاكلات بيئية خطيرة. ومن الطرق الواعدة و الأكثر فعالية لمعالجة التربة الملوثة بالنفط هي المعالجة البيولوجية بل هي الخيار الذي يوفر إمكانية تدمير الملوثات الضارة باستخدام النشاط البيولوجي. تم فحص قدرة الخليط البكتيري لمعالجة التربة الملوثة بالديزل في منظومة bio piling. ومن أجل معالجة سريعة خارج الموقع للتربة الملوثة بالديزل تم اختيار منظومة .bio pilingوقد تم إنشاء منظومتين biopiles على نطاق تجريبي (25 كيلوغراماً من التربة لكل منهما) و يحتويان على التربة الملوثة بما يقرب من 2140 ملغم / كغم من الهيدروكربونات النفطية. التربة المعدلة: (التربة الملوثة مع إضافة المغذيات واللقاح البكتيري) حيث تخلط التربة مع 1.5٪ من نشارة الخشب، ثم زودت بالمغذيات اللازمة وتُسقى يومياً لتوفير الظروف التي تعزز نمو الكائنات الحية الدقيقة. تم تحضير التربة غير المعدلة بوصفها عنصر سيطرة (التربة الملوثة بدون إضافة). جُهز كلا النظامين بالأوكسجين لتوفير الظروف الهوائية،و تم الحضن في درجة حرارة الجو وسُحبت العينات اسبوعياً خلال مدة 35 يوما. تم إزالة 75٪ من إجمالي الهيدروكربونات البترولية من التربة المعدلة و 38٪ من تربة السيطرة في نهاية مدة الدراسة. خلصت الدراسة الى أن تجربة المعالجة البيولوجية خارج الموقع هي الإجراء المفضل،وهي اقتصادية وصديقة للبيئة، وبالتالي تمثل خيارا جيدا لمعالجة التربة الملوثة بالديزل.

Bioremediation of Soil Contaminated with Diesel using Biopile system

This study was focused on biotreatment of soil which polluted by petroleum compounds (Diesel) which caused serious environmental problems. One of the most effective and promising ways to treat diesel-contaminated soil is bioremediation. It is a choice that offers the potential to destroy harmful pollutants using biological activity. The capability of mixed bacterial culture was examined to remediate the diesel-contaminated soil in bio piling system. For fast ex-situ treatment of diesel-contaminated soils, the bio pile system was selected. Two pilot scale bio piles (25 kg soil each) were constructed containing soils contaminated with approximately 2140 mg/kg total petroleum hydrocarbons (TPHs). The amended soil: (contaminated soil with the addition of nutrients and bacterial inoculum), where the soil was mixed with 1.5% of sawdust, then supplied with the necessary nutrients and watered daily to provide conditions promoting microorganism growth. Unamended soil was prepared as a control (contaminated soil without addition). Both systems were equipped with oxygen to provide aerobic conditions, incubated at atmospheric temperature and weekly sampling within 35 days. Overall 75% of the total petroleum hydrocarbons were removed from the amended soil and 38 % of the control soil at the end of study period.
 The study concluded that ex-situ experiment (Bio pile) is a preferable, economical, and environmentally friendly procedure, thus representing a good option for the treatment of soil contaminated with diesel.

Bioremediation of Soil Contaminated with Diesel using Biopile system

This study was focused on biotreatment of soil which polluted by petroleum compounds (Diesel) which caused serious environmental problems. One of the most effective and promising ways to treat diesel-contaminated soil is bioremediation. It is a choice that offers the potential to destroy harmful pollutants using biological activity. The capability of mixed bacterial culture was examined to remediate the diesel-contaminated soil in bio piling system. For fast ex-situ treatment of diesel-contaminated soils, the bio pile system was selected. Two pilot scale bio piles (25 kg soil each) were constructed containing soils contaminated with approximately 2140 mg/kg total petroleum hydrocarbons (TPHs). The amended soil: (contaminated soil with the addition of nutrients and bacterial inoculum), where the soil was mixed with 1.5% of sawdust, then supplied with the necessary nutrients and watered daily to provide conditions promoting microorganism growth. Unamended soil was prepared as a control (contaminated soil without addition). Both systems were equipped with oxygen to provide aerobic conditions, incubated at atmospheric temperature and weekly sampling within 35 days. Overall 75% of the total petroleum hydrocarbons were removed from the amended soil and 38 % of the control soil at the end of study period.
 The study concluded that ex-situ experiment (Bio pile) is a preferable, economical, and environmentally friendly procedure, thus representing a good option for the treatment of soil contaminated with diesel.

Biotreatment of Soil Contaminated with Spent engine Oil by Locally Isolated Microorganisms

Biotreatment of Soil Contaminated with Spent engine Oil by Locally Isolated Microorganisms

Phenanthrene Contaminated Soil Biotreatment Using Slurry Phase Bioreactor

Problem Statement: Polycyclic Aromatic Hydrocarbons (PAHs) are suspected toxins that accumulate in soils and sediments due to their inso lubility in water and lack of volatility. Slurry-ph ase biological treatment is one of the innovative techn ologies that involve the controlled treatment of excavated soil in a bioreactor. Due to highly soil contamination from petroleum compounds in crude oil extraction and also oil refinery sites in Iran, this research was designed based on slurry phase biotreatment to find out a solution to decontaminat ion of oil compounds polluted sites. Approach: Soil samples were collected from Tehran oil refiner y site and Bushehr oil zones. Two compositions of soils (clay and silt) were selected for slurry biot reatment experiment. Soil samples were contaminated with three rates of phenanthrene (a 3 ring PAH), 10 0, 500 and 1000 mg kg -1 and mixed with distilled water in solid concentration of 30% by weight after washing out with strong solvent (hexane) and putting in to the oven. Bacterial consortium was re vived in culture medium which consisted of Mineral Salt Medium (MSM) based on phenanthrene concentrations and ratio of C/N/P in the range of 100/10/2. Prepared soil samples were mixed with dis tilled water, nutrient and bacterial consortium together in the 250 mL glass Erlenmeyer and putted in the shaker incubator with 200 rpm revolutions and 25°C for 7 weeks (45 days). Samples were analyzed for residual phenanthrene, bacterial population every week. For statistical analysis, ge neral linear model with repeated measures (type III ) analysis was applied. Results: The concentration of 100 mg L -l of phenanthrene in clayey and silty soils reached to non detectable limit after 5 and 6 weeks, respectively. While concentration of 500 mg L -l of phenanthrene both in clayey and silty soils rea ched to non detectable limit after 6 weeks. But concentration of 1000 mg L -l both in clayey and silty soil samples has not met this limitation after 7 weeks. Due to presence of Pseudomonas strains in clayey soil samples and their ability i n breaking down of benzene rings, the removal efficiency of ph enanthrene in our slurry bioreactor in clayey soil was a little more than silty soil samples over time . There was a significance relationship between ini tial concentrations of phenanthrene and type of soil wit h time of biotreatment (p<0.001). Conclusion: Therefore, this technology may be applied to remedi ation of small foot print oil contaminated sites, e.g., gas station, oil extraction and refinery site s in Iran, in the case of urgency. Thus this study concludes that the remediation of phenanthrene with concentration up to 1000 mg kg -1 in the oil contaminated sites can be removed to the acceptable limits using slurry based system.

Influence of the application of sugarcane bagasse on lindane (γ-HCH) mobility through soil column: Implication for biotreatment

In the present study we employed sugarcane bagasse for biotreatment of soil containing 50 mg kg −1 of lindane. Garden soil were treated with lindane and amended with varying concentrations of sugarcane bagasse (10%, 20%, 30%, 40% and 50%; w/w). Data on dissipation and degradation of lindane in soil columns (0–15, 15–30 cm) were studied at six consecutive samplings (0, 3, 7, 45 and 60 days). Treatment with 50% sugarcane bagasse resulted in >53% degradation of lindane in upper soil column with minimal leaching to lower soil column (0.002%) while highest leaching of lindane from upper soil column to lower soil column was occurred in garden soil (35.8%). Similarly, a substantial microbial biomass input has detected in amended soil than garden soil. Our results provide evidence that sugarcane bagasse can accelerate lindane degradation by enhanced microbial activity and prevent pesticide mobility through soil column by adsorption. Sugarcane bagasse could be useful as cheaper, easy available alternative for the biotreatment of lindane impacted soil.

Intensification of the aerobic bioremediation of an actual site soil historically contaminated by polychlorinated biphenyls (PCBs) through bioaugmentation with a non acclimated, complex source of microorganisms

BackgroundThe biotreatability of actual-site polychlorinated biphenyl (PCB)-contaminated soils is often limited by their poor content of autochthonous pollutant-degrading microorganisms. In such cases, inoculation might be the solution for a successful bioremediation. Some pure and mixed cultures of characterized PCB degrading bacteria have been tested to this purpose. However, several failures have been recorded mostly due to the inability of inoculated microbes to compete with autochthonous microflora and to face the toxicity and the scarcity of nutrients occurring in the contaminated biotope. Complex microbial systems, such as compost or sludge, normally consisting of a large variety of robust microorganisms and essential nutrients, would have better chances to succeed in colonizing degraded contaminated soils. However, such sources of microorganisms have been poorly applied in soil bioremediation and in particular in the biotreatment of soil with PCBs. Thus, in this study the effects of Enzyveba, i.e. a consortium of non-adapted microorganisms developed from composted material, on the slurry- and solid-phase aerobic bioremediation of an actual-site, aged PCB-contaminated soil were studied.ResultsA slow and only partial biodegradation of low-chlorinated biphenyls, along with a moderate depletion of initial soil ecotoxicity, were observed in the not-inoculated reactors. Enzyveba significantly increased the availability and the persistence of aerobic PCB- and chlorobenzoic acid-degrading cultivable bacteria in the bioreactors, in particular during the earlier phase of treatment. It also markedly enhanced PCB-biodegradation rate and extent (from 50 to 100%) as well as the final soil detoxification, in particular under slurry-phase conditions. Taken together, data obtained suggest that Enzyveba enhanced the biotreatability of the selected soil by providing exogenous bacteria and fungi able to remove inhibitory or toxic intermediates of PCB biodegradation and/or exogenous nutrients able to sustain microorganisms in charge for PCB mineralization.ConclusionEnzyveba appears a promising agent for bioaugmenting actual-site PCB-polluted soils with a native low content of indigenous specialized microflora. This not only for its positive effects on the soil biotreatability but also for its availability on the market at a relatively low cost.

Degradation of Phenanthrene and Pyrene in Soil Slurry Reactors with Immobilized BacteriaZoogloeasp.

The environmental fate of polycyclic aromatic hydrocarbons (PAHs) in soils is motivated by their wide distribution, high persistence, and potentially deleterious effect on human health. Polycyclic aromatic hydrocarbons constitute the largest group of environmental contaminants released in the environment. Therefore, the potential biodegradation of these compounds is of vital importance. A biocarrier suitable for the colonization by micro-organisms for the purpose of purifying soil contaminated by polycyclic aromatic hydrocarbons was developed. The optimized composition of the biocarrier was polyvinyl alcohol (PVA) 10%, sodium alginate (SA) 0.5%, and powdered activated carbon (PAC) 5%. There was no observable cytotoxicity of biocarriers on immobilized cells and a viable cell population of 1.86 x 10(10) g(-1) was maintained for immobilized bacterium. Biocarriers made from chemical methods had a higher biodegradation but lower mechanical strengths. Immobilized bacterium Zoogloea sp. had an ideal capability of biodegradation for phenanthrene and pyrene over a relative wide concentration range. The study results showed that the biodegradation of phenanthrene and pyrene reached 87.0 and 75.4%, respectively, by using the optimal immobilized method of Zoogloea sp. cultivated in a sterilized soil. Immobilized Zoogloea sp. was found to be effective for biodegrading the soil contaminated with phenanthrene and pyrene. Even in natural (unsterilized) soil, the biodegradation of phenanthrene and pyrene using immobilized Zoogloea sp. reached 85.0 and 67.1%, respectively, after 168 h of cultivation, more than twice that achieved if the cells were not immobilized on the biocarrier. Therefore, the immobilization technology enhanced the competitive ability of introduced micro-organisms and represents an effective method for the biotreatment of soil contaminated with phenanthrene and pyrene.

Anaerobic dechlorination of perchloroethylene (PCE) in soil by a dechlorinating microbial consortium

An anaerobic dechlorinating microbial granular consortium was developed for biotreatment of soil contaminated with perchloroethylene (PCE) and trichloroethylene (TCE). Microcosm tests were conducted at ambient temperature (22°C) to examine the performance of PCE dechlorination by this consortium. TCE, dichloroethylene (DCE), and vinyl chloride (VC) were transiently observed as intermediates. Ethylene was the end product of PCE dechlorination. After four months' incubation with the consortium, ethane was observed as a product from reduction of ethylene in microcosms spiked with a low level of PCE (10 mg/kg soil) but not in those with a high PCE level (200 mg/kg soil). At the end of five months, more than 90% of the PCE added to the soil was accounted for, on a molar basis, as ethylene and ethane. The dechlorination was predominately supported by soil organic matter. The dechlorination performance of the consortium was not inhibited whether the soil was spiked with 10 or 200 mg PCE/kg dry soil. The inoculum level influenced the initial dechlorination process, but there was no significant difference in the extent of dechlorination after three months at a low or high level of inoculum (3 or 60 mg VSS/kg soil). Partial and slow dechlorination was also observed in controls without added inoculum due to activity of indigenous soil organisms. In the controls, TCE, cis-1,2-DCE, and VC ware accumulated as intermediates. No dechlorination occurred in soil that was autoclaved and did not receive microbial granules. Methanogenesis was inhibited in the presence of the high initial PCE level (200 mg/kg soil) but not at the low level (10 mg/kg soil).

Development of Bioavailability and Biokinetics Determination Methods for Organic Pollutants in Soil to Enhance In-Situ and On-Site Bioremediation

Determination of biodegradation rates of organics in soil slurry and compacted soil systems is essential for evaluating the efficacy of bioremediation for treatment of contaminated soils. In this paper, a systematic protocol has been developed for evaluating biokinetic and transport parameters in soil slurry and compacted soil bioreactors. The protocol involves abiotic evaluation of adsorption/desorption rates, and equilibria followed by the use of respirometry to determine biodegradation rates using soil slurry, wafer, and porous tube reactors. In the soil slurry reactor, mimicking ex-situ soil biotreatment, degradation occurs in the aqueous phase by suspended microorganisms and by immobilized microbiota present in the soil phase. In a soil wafer reactor, which consists of a thin layer of soil, biodegradation occurs primarily in the soil phase, as compared to the aqueous phase, which consists of free and bound water in and around the soil particles. The wafer reactor represents biotreatment using bioventing or land farming methods. In the porous tube reactor, rate of oxygen diffusion through the compacted soil affects the overall rate of biodegradation. The porous tube reactor represents in-situ biotreatment. Experiments were conducted to determine the cumulative oxygen uptake using an uncontaminated low organic carbon soil with phenol as the spiked contaminant. Detailed mathematical models were developed for each type of soil reactor (slurry, wafer, and porous tube), and these models were fitted to the cumulative oxygen uptake data to derive the best-fit transport and biokinetic parameters. Application of the transport and biokinetic parameters to determine the attainable treatment end points is discussed in this paper.

Continuous, automated and simultaneous measurement of oxygen uptake and carbon dioxide evolution in biological systems

Commercial respirometers are capable of continuously and automatically measuring oxygen uptake in bioreactors. A method for continuously and automatically measuring carbon dioxide evolution can be retrofitted to commercial respirometers. Continuous and automatic measurements of carbon dioxide evolution are achieved by measuring the change in electrical conductivity of barium hydroxide solution. Continuous stirring of the barium hydroxide solution was necessary to prevent the carbon dioxide absorption from controlling the oxygen uptake rate. Three separate experiments (aqueous biodegradation of phenol, soil slurry biotreatment of soil contaminated with phenol, and aqueous biodegradation of crude oil) were conducted to test the oxygen uptake and carbon dioxide evolution measurement system. The respiratory quotient, defined as the ratio of carbon dioxide evolution to oxygen uptake, is close to one until a plateau of oxygen uptake is reached, after which it is greater than one due to degradation of biomass and metabolite products. Unsteady‐state simulation of CO2 evolution in batch reactors, based on the experimental data, showed that carbon dioxide exists primarily as bicarbonate in the liquid phase. The concentration of carbon dioxide in the gas phase is small mainly due to fast reaction with the stirred barium hydroxide solution.

Hydrocarbon degradation in soils and methods for soil biotreatment.

The cleanup of soils and groundwater contaminated with hydrocarbons is of particular importance in minimizing the environmental impact of petroleum and petroleum products and in preventing contamination of potable water supplies. Consequently, there is a growing industry involved in the treatment of contaminated topsoils, subsoils, and groundwater. The biotreatment methodologies employed for decontamination are designed to enhance in situ degradation by the supply of oxygen, inorganic nutrients, and/or microbial inocula to the contaminated zone. This review considers the fate and effects of hydrocarbon contaminants in terrestrial environments, with particular reference to the factors that limit biodegradation rates. The potential efficiencies, advantages, and disadvantages of biotreatment techniques are discussed and the future research directions necessary for process development are considered.