• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.10
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• pp.2771-2778
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• 2009

This study was performed to solve the problem of the 2nd contamination and excessive treatment cost by determining proper quantity of hydrogen peroxide, iron catalyst, mixing method, and input mode that should be provided when Fenton oxidation (this is mostly applied to small contaminated areas such as service station sites) is applied to the excavated and diesel-contaminated soil. Soil artificially contaminated with 10000mg/kg of diesel was used for the experiment. In the batch test, diesel removal seemed to increase as the concentration of hydrogen peroxide increases. When iron catalyst was added, removal efficiency of diesel was much higher than the time when hydrogen peroxide was added solely. The removal efficiency showed greater when Fe(III) was added compared to Fe(II). Column experiment was executed on the basis of results of the batch test to investigate adequate reagent mixing and input methods. The highest efficiency was acquired in the case of separate input mode. Also, it was found that when inputting Fe(III) iron catalyst and separately inputting hydrogen peroxide after dividing the bundle in the column, removal efficiency was 92.8%, which was 9 times greater than that of the first method, 10.5%, when only hydrogen peroxide was added. Thus, it is expected that if the result of this research is applied to Fenton oxidation for the remediation of soil contaminated by diesel, the problem of the 2nd contamination and excessive treatment charge caused by excessive addition of hydrogen peroxide and iron catalyst could be solved.

• Journal of Microbiology and Biotechnology
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• v.16 no.5
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• pp.704-715
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• 2006

Oil spill was found in 1999 from a diesel storage facility located near the top of Baekun Mountain in Uiwang City. Application of bioremediation techniques was very relevant in removing oil spills in this site, because the geological condition was not amenable for other onsite remediation techniques. For efficient bioremediation, bacterial communities of the contaminated site and the uncontaminated control site were compared using both molecular and cultivation techniques. Soil bacterial populations were observed to be stimulated to grow in the soils contaminated with diesel hydrocarbon, whereas fungal and actinomycetes populations were decreased by diesel contamination. Most of the dieseldegrading bacteria isolated from contaminated forest soils were strains of Pseudomonas, Ralstonia, and Rhodococcus species. Denaturing gradient gel electrophoresis (DGGE) analysis revealed that the profiles were different among the three contaminated sites, whereas those of the control sites were identical to each other. Analysis of 16S rDNA sequences of dominant isolates and clones showed that the bacterial community was less diverse in the oil-contaminated site than at the control site. Sequence analysis of the alkane hydroxylase genes cloned from soil microbial DNAs indicated that their diversity and distribution were different between the contaminated site and the control site. The results indicated that diesel contamination exerted a strong selection on the indigenous microbial community in the contaminated site, leading to predominance of well-adapted microorganisms in concurrence with decrease of microbial diversity.

• 한국생물공학회:학술대회논문집
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• 2000.04a
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• pp.418-421
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• 2000

A model was developed to describe the microbial decontamination of diesel contaminated soil in a soil column. The biodegradation rate of diesel in nature depends on temperature and the pH of soil, availability of nutrients, oxygen and water. The soil moisture content is one of the essential factors because it characterizes the availability not only of water to microorganisms but also of oxygen and nutrient dissolved in soil. In this work, the rate of biodegradation was modeled by coupling Michaelis-Menten kinetics for the aqueous-phase solute with adsoption-desoption equation for diesel sorption and desorption from soil.

• Journal of Korean Society on Water Environment
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• v.22 no.5
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• pp.824-830
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• 2006

Several tests were conducted to optimize the design parameters of ln-situ soil flushing processes for diesel contaminated soil. According to the batch extraction test for three anionic surfactants evaluation, Calgonit limiting bubble occurrence was selected for its higher oil cleaning efficiency. After optimum surfactant selection, there were many sets of column flushing test. Over 70% of BTEX was removed in this surfactant dose with 400% of soil volume. In the case of no surfactant addition flushing in column, so called "blank flushing test", BTEX removal rate was 64%. But when we reused the effluent for the cleaning solution, the removal rate was decreased to 46.9%. This result showed reabsorption of oil occurred on the soil. With the addition of Calgonit solution to the diesel contaminated column, BTEX was removed up to 98.9% during the first flushing and 99.4% for the second recirculation flushing. In microcosm tests, diesel contaminated soils were cleaned by both surfactant flushing and biological activities. In anoxic condition, nitrate was used as an electron acceptor while the surfactant and the oil were used an electron donor. BTEX removal efficiency could be achieved up to 80% by biological degradation.

• Journal of Korea Soil Environment Society
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• v.4 no.1
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• pp.49-55
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• 1999

The treatment of petroleum contaminated soil requires various physico-chemical remediation technologies which are efficient in time and can reduce the possibility of secondary contamination by themselves In this study, an innovated soil washing process was proposed to treat the diesel-contaminated soil. Micro-bubbles, which were generated by hydrogen peroxide, deserted and floated the contaminants. Soils less than #60(0.25mm) were artificially contaminated by 6,500mg TPH/kg dry soil initially. The process was examined for pH, the soil to water mixing ratio, concentration of $H_2O$$_2$, and contacting times. In the case of less than #60 soil, maximum removal efficiency(60%) was obtained at pH 12. 1.0% hydrogen peroxide, and 1 : 5 soil to water mixing ratio for 1 hour.

• Microbiology and Biotechnology Letters
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• v.39 no.2
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• pp.161-167
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• 2011

We previously showed that five strains belonging to Pseudomonas could remove TPH (Total Petroleum Hydrocarbons) efficiently when they are applied to TPH-contaminated soil. We optimized the bioremediation condition using different hydrocarbons and nutrients conditions to improve the efficiency. We setup lab-scale column bioreactor to monitor TPH and diesel removal efficiency. When we applied five Pseudomonas sp. mixtures to 25,000 $mg{\cdot}kg^{-1}$ TPH-contaminated soil (diesel 10,000 $mg{\cdot}kg^{-1}$, kerosene 10,000 $mg{\cdot}kg^{-1}$, gasoline 5,000 $mg{\cdot}kg^{-1}$) with the optimum condition, 76.3% of TPH removal efficiency was shown for 25 days. Meanwhile, in the application of five Pseudomonas sp. mixtures to 20,000 $mg{\cdot}kg^{-1}$ diesel-contaminated soil with the optimum condition, 99.2% of diesel removal efficiency was shown for 40 days. In the application to lab-scale bioreactor with five high efficiency bacteria, 88.5% of TPH removal efficiency was shown for 45 days. Based on the results from this study, we confirmed that this mixed Pseudomonas sp. consortium might improve the bioremediation of TPH in contaminated soil, the efficacy can be controlled by improving the nutrients. We also confirmed that the nutrients and oxygen for biodegradation of TPH could contribute on the management and control of applications of these strains for the study of bioremediation of TPH-contaminated soil.

• Journal of Korea Soil Environment Society
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• v.4 no.2
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• pp.193-201
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• 1999

This study was conducted to check the applicability of pilot-scale co-composting for the remediation of diesel contaminated soil during the winter. Nutrients and microbes were added to enhance the efficiency of bioremediation and fermenting composts were also added to stimulate the microbial activities. As a result. the soil pile was kept at adequate temperature for the bioremediation during the test period of 30∼40 days and initial concentration(2,340mg TPH/kg dry soil) was reduced to 216mg TPH/kg dry soil (approximately 91% removal). During the initial 10∼30 days, it was found that the TPH concentration and the microbial population were rapidly reduced and increased. respectively. The co-composting technology studied can be effectively applied to remediate the diesel contaminated soil during the winter.

• Journal of Soil and Groundwater Environment
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• v.13 no.2
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• pp.30-35
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• 2008

In this study, the feasibility of soil washing, chemical oxidation and sonication was investigated to treat lubricantcontaminated railroad soil. Tergitol, a non-ionic surfactant, was used as a washing agent with or without iso-propyl acohol as a cosolvent. However, it was not effective to remove lubricant from soil even though tergitol was the most effective washing agent for diesel-contaminated soil. The cosolvent reduced the overall washing efficiency. Chemical oxidation removed 30% of lubricant from contaminated soil. Soil washing after chemical oxidation extracted additionally 16-17% of lubricant. Sonication enhanced-soil washing showed enhanced overall efficiency of soil washing. Lubricant-contaminated soil should be remediated by the other technology used for diesel-contaminated soil.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.10
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• pp.1825-1832
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• 2000

Column experiments were conducted by using soil columns, to investigate feasibility and efficiency of in-situ ozone enhanced remediation for diesel-contaminated soil. The injection of gaseous ozone into soil column revealed the enhanced decomposition of ozone due to the catalytic reaction between ozone and metal (e.g., Fe, Mn etc.) oxides as evidenced by as much as 25 times shorter half-life of ozone in a sand packed column than in a glass beads packed column. Substantial retardation in the transport of and the consumption of ozone were observed in the diesel contaminated field soil and sand packed columns. After 16 hrs ozonation, 80% of the initial mass of diesel (as diesel range organic) concentration of $800{\pm}50mg/kg$, was removed under the conditions of the flow rate of 50mL/min and $6mg-O_3/min$. Whereas, less than 30% of diesel was removed in the case of air injection. Analysis of the residual TPH(total petroleum hydrocarbon) and selected 8 aliphatics of diesel compounds in the inlet and the outlet of the column confirmed that diesel nonselectively reacted with ozone and then shifted to lower carbon numbered molecules. Water content also was found to be an important parameter in employing ozone to the hydrocarbon-contaminated soil.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2003.04a
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• pp.124-127
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• 2003

Laboratory scale experiments on in-situ ozonation were carried out to delineate the effects of liquid phases, such as soil water and nonaqeous phase liquid (NAPL) on the transport of gaseous ozone in unsaturated soil. Soil water enhanced the transport of ozone due to water film effect, which prevent direct reaction between soil particles and gaseous ozone, and increased water content reduced the breakthrough time of ozone because of increased average linear velocity of ozone and decreased air-water interface area. Diesel fuel as NAPL also played a similar role with water film, so the breakthrough time of ozone in diesel-contaminated soil was significantly reduced compared with uncontaminated soil. However, ozone breakthrough time was retarded with increased diesel concentration, because of high reactivity of diesel fuel with ozone. In multiphase liquid system of unsaturated soil, the ozone transport was mainly Influenced by nonwetting fluid, diesel fuel in this study.