• 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.

• Journal of Korean Society on Water Environment
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• v.30 no.4
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• pp.403-408
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• 2014

The toxicity of heavy metals (Zn, Pb) and diesel, in single and binary solution was investigated using the photobacterium Vibrio fischeri (Microtox test) as a test organism. In this experiment, the concentration of water soluble fraction of diesel was based on the total petroleum hydrocarbon (TPH). The toxicity of each single compound showed the following $EC_{50}$ (15min): Zn 1.90 mg/L, Pb 0.31 mg/L, TPH 2.09 mg/L. The observed toxicity of binary mixtures increased, depending on the concentration of the mixed substance. The effects were defined as synergistic, antagonistic, or additive, in accordance with the sign of difference between the predicted and observed toxicity at binary mixtures. The interactive effects between zinc and lead were synergistic, on the other hand, antagonistic and additive effects were found in each metal and TPH mixtures on the bioluminescence of V. fischeri.

• Resources Recycling
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• v.20 no.3
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• pp.62-67
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• 2011

This study has been investigated for characteristic of removal on the effect of changes in soil moisture, microwave power, and temperature through the decomposition of oil-contaminated soil under high temperature conditions with high temperature heating elements and microwave. A lubricating oil having long carbocyclic(C18-C50) commonly known as a non-resolvable material was treated and the efficient for removal of TPH(Total Petroleum Hydrocarbon) obtained 85.2% at 6 kW and $700^{\circ}C$ and thus the contaminant was found to be removed to 1788 mg/kg for 40 minutes. In case of contaminated soil by light oil and gasoline, the amount of removal was achieved with 567 mg/kg at 6 kW, 500 for 20 minutes that corresponds to reach 98.4% of treatment efficient. In addition, non-resolvable materials contaminated by oil reached TPH concentration on 2,000 mg/kg of worrisome level of soil contamination in the 3-zone at 6kW, $700^{\circ}C$, and 30 minutes, and processing cost at this time was about 8,173 won per ton.

• Journal of Soil and Groundwater Environment
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• v.13 no.5
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• pp.81-87
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• 2008

In accompany with the transfer of US army bases, recent surveys reported serious contamination of soils by the release of petroleum from storage facilities and heavy metals accumulated in rifle-ranges. These problems have made an increased concerns of cleanup technology for contaminated soils. In this study, a full-scale soil washing process improved by multistage continuous desorption and agitational desorption techniques was examined for petroleum-contaminated soils obtained from three different remedial sites that contained 29.3, 16.6, and 7.8% of silt and clay, respectively. The initial concentrations of total petroleum hydrocarbon (TPH) were 5,183, 2,560, and 4,860 mg/kg for each soil. Pure water was applied to operate washing process, in which water used for washing process was recycled 100% for over 6 months. The results of full-scale washing tests showed that the TPH concentrations for soils (> 3.0 mm) were 50${\sim}$356 mg/kg (85.2${\sim}$98.2% removal rates), regardless of the contents of silt and clay from in A, B and C soil, when the soils were washed at 3.0 kg/$cm^2$ of injection pressure with the method of wet particle separation. Based on the initial TPH concentration, the TPH removal rates for each site were 85.2, 98.2 and 89.9%. For soils in the range of 3.0${\sim}$0.075 mm, the application of first-stage desorption technique as a physical method resulted 834, 1,110, and 1,460 mg/kg of TPH concentrations for each soil, also additional multi-stage continuous desorption reduced the TPH concentration to 330, 385, and 245 mg/kg that were equivalent to 92.4, 90.6, and 90.1% removal rates, respectively. The result of multi-stage continuous desorption for fine soil (0.075${\sim}$0.053 mm) were 791, 885, and 1,560 mg/kg, and additional agitation desorption showed 428, 440, and, 358 mg/kg of TPH concentrations. Compared with initial concentration, the removal rates were 92.0, 93.9 and 92.9%, respectively. These results implied we could apply strategic process of soil washing for varies types of contaminated soils to meet the regulatory limit of TPH.

• Journal of Korean Society on Water Environment
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• v.23 no.5
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• pp.665-675
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• 2007

In-situ Air Sparging (IAS, AS) is a remediation technique in which organic contaminants are volatilized from saturated zone to unsaturated layer. This study focuses on the removal and interaction of Volatile Organic Compounds (VOCs) and $CO_2$, and Total Petroleum Hydrocarbon (TPH) in saturated and unsaturated, and air space zone on the unsaturated soil surface. Soil sparging temperature of hot air has risen to $34.9{\pm}2.7^{\circ}C$ from $23.0{\pm}1.9^{\circ}C$ for 36 days. At the diffusing point, fluid TPH concentrations were reduced to 78.7% of the initial concentration in saturated zone when hot air was sparged. The TPH concentrations were decreased to 66.1% for room temperature air sparging. The amount of VOCs for hot air sparging system, in air space, was approximately 26% larger than constant air sparging system. The amount of $CO_2$ was 4,555 mg (in unsaturated zone) and 4,419 mg (in air space) when hot air was sparged was 3,015 mg (in unsaturated zone) and 3,634 mg (in air space) for room air temperature in the $CO_2$ amount. The removals of VOCs and biodegradable $CO_2$ through the hot air sparging system (modified SVE) were more effective than the room temperature air sparging. The regression equation were $Y=976.4e^{-0.015{\cdot}X}$, $R^2=0.98$ (hot air sparging) and $Y=1055e^{-0.028{\cdot}X}$, $R^2=0.90$ (room temperaure air sparging). Estimated remediation time was approximately 500 days, if final saturated soil TPH concentration was set to 1.2 mg/L application of tail effect.

• Economic and Environmental Geology
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• v.52 no.1
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• pp.1-12
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• 2019

Batch experiments for the soil washing coupled with the magnetic separation process were performed to remediate the soil contaminated with metal and oil wastes. The soil was seriously contaminated by Zn and TPH (total petroleum hydrocarbon), of which concentrations were 1743.3 mg/kg and 3558.9 mg/kg, respectively, and initial concentrations of Zn, Pb, Cu, and TPH were higher than the 2nd SPWL (soil pollution warning limit: remediation goal). The soil washing with acidic solution was performed to remove heavy metals from the soil, but Pb and Zn concentration of the soil maintained higher than the 2nd SWPL even after the soil washing with acidic solution. The 2nd soil washing was repeated to increase the Pb and Zn removal efficiency and the Zn and Pb removal efficiencies additionally increased by only 8 % and 5 %, respectively, by the 2nd soil washing (> 2nd SPWL). The small particle separation from the soil was conducted to decrease the initial concentration of heavy metals and to increase the washing effectiveness before the soil washing and 4.1 % of the soil were separated as small particles (< 0.075 mm in diameter). The small particle separation lowered down Zn and Pb concentrations of soil to 1256.3 mg/kg (27.9 % decrease) and 325.8 mg/kg (56.3 % decrease). However, the Zn concentration of soil without small particles still was higher than the 2nd SPWL even after the soil washing, suggesting that the additional process is necessary to lower Zn concentration to below the 2nd SPWL after the treatment process. As an alternative process, the magnetic separation process was performed for the soil and 16.4 % of soil mass were removed, because the soil contamination was originated from unreasonable dumping of metal wastes. The Zn and Pb concentrations of soil were lowered down to 637.2 mg/kg (63.4 % decrease) and 139.6 mg/kg (81.5 % decrease) by the magnetic separation, which were much higher than the removal efficiency of the soil washing and the particle separation. The 1st soil washing after the magnetic separation lowered concentration of both TPH and heavy metals to below 2nd SPWL, suggesting that the soil washing conjugated with the magnetic separation can be applied for the heavy metal and TPH contaminated soil including high content of metal wastes.

• Journal of Microbiology and Biotechnology
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• v.14 no.5
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• pp.901-905
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• 2004

The degradation and mineralization of crude oil were investigated over 50-days in three soils, loamy sand, sand, and combusted loamy, which were artificially contaminated with crude oil (50 g $kg^{-1}$) and inoculated with Nocardia sp. H17-1. The degradation efficiency of total petroleum hydrocarbon (TPH) in sand was the highest at 76% among the three soils. The TPH degradation rate constants $(k_{TPH})$ in loamy sand, sand, and combusted loamy sand were 0.027 $d^{-1}$, 0.063 $d^{-1}$, and 0.016 $d^{-1}$, respectively. In contrast, the total amount of $CO_2$ evolved was the highest at 146.1 mmol in loamy sand. The $CO_2$ evolution rate constants (k_{CO2})$ in loamy sand, sand, and combusted loamy sand were 0.057 $d^{-1}$, 0.066 $d^{-1}$, and 0.037 $d^{-1}$, respectively. Therefore, it seems that the degradation of crude oil in soils can be proportional to the soil pore space and that mineralization can be accelerated with the increase of organic substance.

• Journal of the Korean GEO-environmental Society
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• v.11 no.5
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• pp.5-13
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• 2010

The research is intended to develop and verify a biological complex soil treatment process to treat and restore soil and groundwater which is contaminated with oil, heavy metals, and nutrients through experiments with the series of treatment process such as bioreactor, rolled pipe type of contact oxidation system(RPS), and chemical processing system. 5 microbial strains were separated and selected through experiment, whose soil purification efficiency was excellent, and it was noted that anion- and nonion-series of complex agent was most excellent as a surfactant for effectively separating oils from soils. Method to mix and apply selected microbes after treating the surfactant in the contaminated soil was most effective. The removal efficiencies of total petroleum hydrocarbon (TPH)-contaminated soil about 5,000mg/L and above 10,000mg/L were approximatly 90.0% for 28 days and 90.7% for 81 days by soil remediation system and the average removal efficiencies of BOD, $COD_{Mn}$, SS, T-N, and T-P in leachate were 90.6, 73.0, 91.9, 73.8, 65.7% by the bioreactor and RPS. The removal efficiency was above 99.0% by chemical processing system into cohesive agents.

• Journal of Environmental Science International
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• v.17 no.7
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• pp.795-799
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• 2008

We have studied bioremediation of effective microorganisms on crude oil spill in Taean, west-coast of Korea. Oil contaminated soil samples were collected on December 14, 2007, seven days after the Hebei Spirit oil-spilled accident. Total petroleum hydrocarbon (TPH) was measured to evaluate the effectiveness of effective microorganisms (EM) which were composed with yeast, photosynthetic bacteria and lactic acid bacteria on oil degradation. TPH concentration before EM treatment was 323.8 mg/kg, whereas TPH concentrations on 2 days after EM treatment and that of control (without EM) was 102.1 mg/kg and 170.6 mg/kg, respectively. On six days after EM treatment TPH was 91.3 mg/kg and that of control was 127.7 mg/kg. Percentages of degraded crude oil were 47.3% without EM and 68.5% with EM, 60.6% without EM and 71.8% with EM on 2 and 6 days after EM treatment, respectively. These results clearly showed that the application of effective microorganisms toward oil-contaminated soil was quite useful to degrade crude oil spill. These results were derived from the effects of biostimulation of microbial media nutrients and bioaugmentation of effective microorganisms. If we carefully apply these effective microorganisms, it can be a useful bioremediation method to recover oil-contaminated marine ecosystems.

• Journal of Microbiology and Biotechnology
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• v.19 no.4
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• pp.339-345
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• 2009

We evaluated the activity and abundance of the crude-oil-degrading bacterium Nocardia sp. H17-1 during bioremediation of oil-contaminated soil, using real-time PCR. The total petroleum hydrocarbon(TPH) degradation rate constants(k) of the soils treated with and without H17-1 were $0.103\;d^{-1}$ and $0.028\;d^{-1}$ respectively. The degradation rate constant was 3.6 times higher in the soil with H17-1 than in the soil without H17-1. In order to detect and quantify the Nocardia sp. H17-1 in soil samples, we quantified the genes encoding 16S ribosomal RNA(16S rRNA), alkane monooxygenase(alkB4), and catechol 2,3-dioxygenase(23CAT) with real-time PCR using SYBR green. The amounts of H17-1 16S rRNA and alkB4 detected increased rapidly up to 1,000-folds for the first 10 days, and then continued to increase only slightly or leveled off. However, the abundance of the 23CAT gene detected in H17-1-treated soil, where H17-1 had neither the 23CAT gene for the degradation of aromatic hydrocarbons nor the catechol 2,3-dioxygenase activity, did not differ significantly from that of the untreated soil($\alpha$=0.05,p>0.22). These results indicated that H17-1 is a potential candidate for the bioaugmentation of alkane-contaminated soil. Overall, we evaluated the abundance and metabolic activity of the bioremediation strain H17-1 using real-time PCR, independent of cultivation.