• Economic and Environmental Geology
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• v.43 no.1
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• pp.13-20
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• 2010

Acid mine drainage (AMD) from abandoned mine sites typically has low pH and contains high level of various heavy metals, aggravating ground- and surface water qualities and neighboring environments. This study investigated removal of heavy metals in a biological treatment system, mainly focusing on the removal by adsorption on a substrate material. Bench-scale batch experiments were performed with a mushroom compost to evaluate the adsorption characteristics of heavy metals leached out from a mine tailing sample and the role of SRB in the overall removal process. In addition, adsorption experiments were perform using an artificial AMD sample containing $Cd^{2+}$, $Cu^{2+}$, $Pb^{2+}$ and $Zn^{2+}$ to assess adsorption capacity of the mushroom compost. The results indicated Mn leached out from mine tailing was not subject to microbial stabilization or adsorption onto mushroom compost while microbially mediated stabilization played an important role in the removal of Zn. Fe leaching significantly increased in the presence of microbes as compared to autoclaved samples, and this was attributed to dissolution of Fe minerals in the mine tailing in a response to the depletion of $Fe^{3+}$ by iron reduction bacteria. Measurement of oxidation reduction potential (ORP) and pH indicated the reactive mixture maintained reducing condition and moderate pH during the reaction. The results of the adsorption experiments involving artificial AMD sample indicated adsorption removal efficiency was greater than 90% at pH 6 condition, but it decreased at pH 3 condition.

• Economic and Environmental Geology
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• v.53 no.4
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• pp.441-477
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• 2020

There have been raised other environmental issues related to remediated soils piled up in numerous carry-out processing facilities because a considerable quantity of them have been produced every year, but most of them have not been relevantly reused or recycled. Thus, this article reports the trend of researches on the development of techniques to restore the quality of remediated soils to activate their reuse and recycling. Firstly, the tendency of change in soil properties through remediation processes was looked over, and then the degradation of soil quality was characterized according to the type of remediation processes. Besides, the direction of policy to promote the reuse and recycling of remediated soils was introduced, and finally, the future works needed were suggested. This article was prepared based on the results of the survey of domestic and foreign literature. A number of literature were reviewed to scrutinize the change of soil properties due to remediation processes and diverse techniques for the amendment and restoration of remediated soils. Furthermore, the policies related to the reuse and recycling of remediated soils were arranged with the reference of the first and second versions of the Soil Conservation Master Plan of Korea. The literature survey focused on three kinds of remediation technologies, such as land farming, soil washing, and thermal desorption, which were most frequently used so far in Korea. The results indicate that the tendency of change in soil properties was significantly different depending on the type of remediation processes applied, and the degradation characteristics of soil quality were also totally different between them. The soil amendment and restoration can be categorized as three techniques depending on the type of substances used, such as inorganic, organic, and biological ones. Diverse individual materials have been used, and the soil properties improved or enhanced were dependent on the type of specific materials utilized. However, few studies on the restoration of soil qualities degraded during the remediation processes have not been carried out so far. The second Soil Conservation Master Plan states the quality certification and target management system of remediated soils, and it is expected that their reuse and recycling will be facilitated hereafter. With the consideration of the type of remediation processes implemented and public utility, the restoration technologies of remediated soils should be developed for the vitalization of their reuse and recycling. Besides, practical and specific measures should be taken to support the policy specified in the second Soil Conservation Master Plan and to promote reuse/recycling of remediated soils.

• Economic and Environmental Geology
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• v.47 no.1
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• pp.39-48
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• 2014

In coastal region, estuaries have complex environments where dissolved and particulate matters are mixed with marine water and substances. Suspended sediment (SS) dynamics in coastal water, in particular, plays a major role in erosion/deposition processes, biomass primary production and the transport of nutrients, micropollutants, heavy metals, etc. Temporal variation in suspended sediment concentration (SSC) can be used to explain erosion/sedimentation patterns within coastal zones. Remotely sensed data can be an efficient tool for mapping SS in coastal waters. In this study, we analyzed the variation in SSC in coastal water using the Geostationary Ocean Color Imager (GOCI) and Landsat Enhanced Thematic Mapper Plus (ETM+) in Gyeonggi-bay. Daily variations in GOCI-derived SSC showed low values during ebb time. Current velocity and water level at 9 and 10 am is 37.6, 28.65 $cm{\cdot}s^{-1}$ and -1.23, -0.61 m respectively. Water level has increased to 1.18 m at flood time. In other words, strong current velocity and increased water level affected high SSC value before flood time but SSC decreased after flood time. Also, we compared seasonal SSC with the river discharge from the Han River and the Imjin River. In summer season, river discharge showed high amount, when SSC had high value near the inland. At this time SSC in open sea had low value. In contrast, river discharge amount from inland showed low value in winter season and, consequently, SSC in the open sea had high value because of northwest monsoon.

• Economic and Environmental Geology
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• v.48 no.6
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• pp.491-500
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• 2015

Batch experiments were performed to determine the feasibility of the surfactant-enhanced soil washing process at various washing conditions for the Kuwait soil seriously contaminated with the crude oil. The soil was sampled at a dried oil pond in Kuwait and its average TPH concentration was 223,754 mg/kg, which was too high to apply the conventional remediation process. Nine commercialized non-ionic surfactants were used for the batch experiment to measure the surfactant solubility for the crude oil because it was reported that they have worked for the soil remediation. Among them, three surfactants having high crude oil solubility were used for the soil washing experiment. From the result of batch experiment, 5% TritonX-100 washing solution showed the highest TPH removal efficiency (67%) for the crude oil contaminated soil. However, because the residual TPH concentration in the washed soil was still higher than the clean-up level in Kuwait (10,000 mg/kg), the repeated soil washing was performed. After five washings with 2% surfactant solution, the cumulative TPH removal efficiency was higher than 96% and the residual TPH concentration in the soil went down below the clean-up level. To measure the desorption capacity of TritonX-100 remained in the soil after the soil washing, the silica beads and the soil were washed five times with 2% TritonX-100 surfactant solution and then they were washed again with distilled water to detach the surfactant adsorbed on beads or soil. After five washings with surfactant solution, 7.8% and 19.6% of the surfactant was adsorbed on beads and soil, respectively. When additionally washed with distilled water, most of the residual surfactant were detached from beads and only 4.3% of surfactant was remained in soil. From the results, it was investigated that the surfactant-enhanced soil washing process with TritonX-100, Tergitol S-15-7, and Tergitol S-15-9 has a great capability for the remediation of the Kuwait soil seriously contaminated by crude oil (more than 220,000 mg/kg).

• Korean Journal of Plant Resources
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• v.18 no.1
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• pp.1-7
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• 2005

This study was conducted to investigate the possibility of cultivating tea plants planted in the mountain area of west Gyeongnam province, Korea for 2 years from March 27th, 2001 to July 30th 2003. Ninety each plants collected from 5 different sife were cultivated in nursery cup pot$(\phi\;16cm)$. in the greenhouse condition and transplanted in 5 different location and monitored their survival growing state etc. The results obtained are as follow : 1. Survival rate tea plants after transfer to soil was relatively high Gaya-myeon Hanyang-gun with $90.0\%$ and the lowest in Buksang-meyon Geochang-gun with $80.0\%$. The tea plant collected from Gaya-myeon showed the best growing activity at early stage. 2. For the second year of harvesting time, survival rate was the highest in Machun-myeon Hamyang-gun with $92.2\%$ and the lowest was Buksang-myeon Geochang-gun with $76.7\%$. 3. For the 3rd year of harvesting time, it was impossible to data collection because of the most upper parts of plants were killed by severe freezing weather condition. In the Baekjeon-myeon, Hamyang-gun Buksang-myeon, Ungyang-myeon Geochang-gun, which are severly cold$(below\;-10^{\circ}C)$ in winter season, seems not a suitable places for tea plant cultivation since it is very different to harvest the young loaves in growing season. In conclnsion we could select two sites Gaya-myeon, Hapcheon-gun, Machun-myeon, Hamyang-gun, as tea plant cultivation in the mountain area of west-Gyeongnam province, korea.

• Resources Recycling
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• v.29 no.2
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• pp.55-61
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• 2020

Selective catalytic reduction (SCR) has been a promising technology to reduce the air pollution caused by nitrogen oxides (NOx) in several industries. The consumption of SCR catalysts increases every year as technology evolves, however those have a limited lifespan and usually end up in landfills after they deactivate. Currently, the most widely used catalyst for and stationary applications is V₂O₅-WO₃/TiO₂ which can contain around 50% wt V₂O₅ and 7-10% wt of WO₃. The vast uses for both vanadium and tungsten and the worldwide interest in recycling methods that allow for the extraction of metals from secondary sources represent the major motivation for this research. The extraction time, pH dependency, extraction concentration studies were carried out using Aliquat 336 in exxol D80 as the extractant. It was determined that to optimize the extraction of both metals 30min of contact time with an organic phase containing 0.5mol/L of Aliquat 336 are needed at a slightly acidic pH (~5.0). In addition, counter McCabe-Thiele studies allowed us to determine that one stage is necessary for the removal of 99% of vanadium while 2 stages are necessary for the extraction of tungsten and counter current simulations proved that the theoretical approach was correct.

• Economic and Environmental Geology
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• v.43 no.6
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• pp.555-564
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• 2010

Remediation process by using the bio-carrier (beads) with dead Bacillus sp. B1 and polysulfone was investigated for heavy metal contaminated groundwater. Sorption batch experiments using the bio-carrier were performed to quantify the heavy metal removal efficiencies from the contaminated solution. The analyses using SEM/EDS and TEM for the structure and the characteristic of precipitates on/inside the beads were also conducted to understand the sorption mechanism by the bio-carrier. Various amounts of freeze-dried dead Bacillus sp. B1 were mixed with polysulfone + DMF(N,N-dimethylformamide) solution to produce the bio-carrier (beads; less than 2mm in diameter) and 5% of Bacillus sp. B1 in the bio-carrier was optimal for Pb removal in the solution. The removal efficiency ratings of the bio-carrier for Pb, Cu and Cd were greater than 80% after adding 2g of bio-carrier in 50ml of aqueous solution (<10mg/L of each heavy metal concentration). Reaction time of the bio-carrier was very fast and most of the sorption reaction for heavy metals were completed within few hours. Batch experiments were duplicated at various pH conditions of aqueous solutions and Cu and Pb removal efficiencies highly maintained at wide pH ranges (pH 2-12), suggesting that the bio-carrier can be useful to clean up the acidic waste water such as AMD. From SEM/EDS and TEM analyses, it was observed that the bio-carrier was spherical shape and was overlapped by many porous layers. During the sorption experiment, Pb was crystallized on the surface of porous layers and also was mainly concentrated at the boundary of Bacillus sp. B1 stroma and polysulfone substrate, showing that the main mechanism of the bio-carrier to remove heavy metals is the sorption on/inside of the bio-carriers and the bio-carriers are excellent biosorbents for the removal of heavy metal ions from groundwater.

• Journal of the Geological Society of Korea
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• v.54 no.6
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• pp.587-603
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• 2018

3-D petroleum system modeling was performed on the Jeju Basin, offshore southern Korea to analyze the hydrocarbon migration and accumulation as well as the generation and expulsion of the hydrocarbon, based on subsurface structure maps of respective sedimentary formations. The lowermost formation deposited in Eocene time was assigned as a source rock, for which a mixed kerogen of type II and III was input in the modeling of oil and gas generation in consideration of the sedimentary environment of fluvio-lacustrine condition. Initial TOC was 4% as an input, based on the analysis of the well data and sedimentary environment. The modeling results show that a considerable amount of hydrocarbons was generated and expelled from the source rocks at the western Joint Development Zone (JDZ) sub-block 4, where the hydrocarbons was migrated to the above reservoir rocks at 20 Ma. The oil and gas in the reservoir rocks of the JDZ sub-block 4 are accumulated into the prospects with closure structures that has already been formed at the nearby areas. Another generation of hydrocarbon occurs from the source rock at the eastern border area of JDZ sub-block 1 and 2, where the expulsion of the hydrocarbons occurs at 10 Ma from the source rock into the above reservoir rocks, in which the accumulation also is expected. The generation, migration and accumulation were retarded at the eastern area of the JDZ sub-block 1 and 2, compared with the area of the western JDZ sub-block 4. Based on the modeling results, it is estimated that gases migrated laterally and vertically in long distance whereas oil migrated laterally in shorter distance than gases. A substantial amount of hydrocarbon could have seeped out of the reservoir formations to the surface since the migration of oil and gas actively occurred in Miocene time before the formation of seals. However, the modeling shows that the hydrocarbon could be accumulated smoothly into the closed structures that can be formed locally by alternation of sand and shale beds.

• Korean Journal of Plant Resources
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• v.31 no.4
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• pp.283-293
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• 2018

This study was performed to analysis of chemical constituent in Polygonum multiflorum root (PMR) by different dry methods (hot-air dry, shade dry, and freeze dry). The results are summarized as followings; major free sugar were detected fructose, glucose, and sucrose in dried PMR based on various dry methods. The highest content of free sugars was found in freeze dried PMR. The four organic acids were detected in dried PMR by HPLC analysis. The content of oxalic acid in shade dried PMR was higher than the dried PMR by different dry methods. The content of total amino acid and essential amino acids were high in the orders of freeze drying > shade drying > hot-air drying. The potassium and magnesium levels of freeze dried PMR was significantly higher than the other drying method of PMR. Whereas the calcium and sodium levels were higher in hot-air dried PMR. The major fatty acids were determined the linoleic acid in PMR by different dry methods.

• Journal of the Korea Organic Resources Recycling Association
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• v.19 no.1
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• pp.123-130
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• 2011

Objectives of this study were to compare the environmental effects of digestates produced in bioenergy village on the rice paddy field for recycling. Digestates were applied to the soils and the soil properties and the crop responses were analyzed according to the standard methods of soil evaluation. Plant height and the number of tiller showed similar results in both the conventional and digestate treated field, and the yield of rough rice was higher in the field treated with digestates than that with chemical fertilizer. The amounts of nitrogen absorbed in straw and grain were larger in the digestates-treated field than chemical fertilizer-treated one, and efficiency of nitrogen applied was shown to be the highest in 100% treated digestate of the pig manure. Exchangeable cation and pH increased in the soil treated with digestate after harvesting, but salt was not accumulated. With these results, it was concluded that resource recycling in green town can be facilitated through the securement of arable lands for the application of digestates and the proper use of these fertilizers. Long-term effects of digestate application on the soil environment should be sustainingly studied.