• Journal of the Korean GEO-environmental Society
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• v.25 no.3
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• pp.5-11
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• 2024

Promising geological structures for carbon dioxide capture and subsurface storage include aquifers, depleted reservoirs, and gas fields. Among these, aquifers are gaining attention due to their potential for storing significant amounts of carbon dioxide compared to other geological structures. Therefore, there is a growing interest in enhancing carbon dioxide storage efficiency by understanding the characteristics of aquifers and developing technologies tailored to their properties. In this study, the storage efficiency of carbon dioxide injection following surfactant pre-injection into porous micro-models was evaluated. The results indicate that as the concentration of the surfactant solution injected prior to carbon dioxide injection increases, storage efficiency improves. Conversely, lower concentrations require more surfactant injection to enhance storage efficiency. Furthermore, under identical surfactant concentration conditions, the storage efficiency from surfactant pre-injection prior to supercritical carbon dioxide injection is approximately 30% lower compared to surfactant-co-solvent substitution as observed in previous studies. However, under the maximum concentration conditions investigated in this study, similar storage efficiencies to those of previous studies were achieved. These findings are expected to guide concentration determinations for surfactant application aimed at enhancing carbon dioxide storage efficiency in aquifers in future studies.

• Proceedings of the Korean Society for Food Science of Animal Resources Conference
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• 2004.10a
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• pp.227-230
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• 2004

본 연구에서는 신선육 및 원료육의 미생물 저감화 및 안전성 확보를 위해 식육에 초임계 이산화탄소 처리를 실시하였다. 이산화탄소의 초임계점인 78 atm, $38^{\circ}C$에서 10분 처리한 시료에서 병원성 미생물의 저감화가 나타나기 시작했으며, 압력을 100 atm 이상으로 증가시켰을 때 5 log 이상의 억제 효과가 나타나 신선육 및 원료육의 미생물학적 안전성이 검증되었다. 하지만 초임계 이산화탄소의 압력을 증가시킬수록 안정성은 확보되는 반면 시료의 구조${\cdot}$물성 변이가 심화되어 원료육의 가공적성도는 떨어지는 것으로 판단된다. 따라서 신선육 및 원료육의 품질을 고려한 미생물적 안전성을 확보하려면, 이산화탄소의 초임계점수준의 처리가 요구되며, 향후 초임계 이산화탄소 처리에 따른 육질변이 및 가공적성도에 대한 다각적이고 심도 있는 연구가 요구된다.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2003.11a
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• pp.506-507
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• 2003

전 세계적으로 이산화탄소를 저감하기 위한 연구활동이 활발히 진행중이나 현재까지는 산업생산성에 영향을 미치지 않을 정도로 경제적인 이산화탄소 저감법은 개발이 되지 않은 실정이다. 미국, 일본 등 선진국을 중심으로 각국별 사정에 맞는 이산화탄소 저감법을 연구중인데, 대표적인 기술로는 흡수법, 흡착법, 생물학적 고정화, 막분리법, 심냉법, 산소연소법 등이 있다. 각 기술별로 장·단점이 있지만 배출되는 이산화탄소 중 보다 많은 양을 줄이기 위해서는 발전소, 철강업 그리고 시멘트업 등과 같은 대규모 발생원에서 발생되는 배기가스 중 함유된 이산화탄소를 저감하는 것이 효율적이다.(중략)

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 1995.11a
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• pp.33-37
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• 1995

최근 문제시 되고있는 지구온난화 현상은 태양으로부터 발산된 태양파 중 지구 표면에 흡수되지 않은 일부 반사 에너지파와 지구표면 자체에서 발산하는 에너지파가 온난화가스들에 의하여 대기권 밖으로 발산되지 못하고 흡수되어 대기의 온도를 상승시키는 것에 기인한다. 이산화탄소는 이와같은 지구온난화 현상에 절반 이상의 영향을 미치고 있으며, 날로 증가하는 에너지 소모량에 의하여 대기중 이산화탄소의 농도가 계속 증가하고 있다. 따라서, 1988년 토론토 회의 이후, 각종 국제회의에서 이산화탄소 배출 규제문제가 논의되고 있으며, 연소 배 가스로부터 이산화탄소를 제거하는 기술에 대한 관심이 높아지고 있다. 각종 지구온난화 가스의 분리 회수기술로는 흡수법, 흡착법, 막분리법, 산소연소법 등이 개발되어 있으나, 이산화탄소의 경우 상용화 되어있는 분리기술은 흡수법으로서, 알카놀아민을 이용한 화학흡수법이 가장 널리 사용되고 있다.(중략)

• Proceedings of the Membrane Society of Korea Conference
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• 1994.10a
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• pp.24-25
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• 1994

고분자 분리막을 통한 메탄과 이산화탄소의 분리는 천연가스에서 불순물로 작용하는 이산화탄소를 분리시켜 천연가스의 순도를 향상시키는데 활용할 수 있으며, 바이오가스나 제철소 폐가스로부터의 이산화탄소의 분리, enhanced oil revovery 공정에서의 이산화탄소의 분리, 그리고 지구 온난화의 원인이 되는 대기중의 이산화탄소 농도의 감소등에서 활용될수 있다. 이러한 분리막 공정은 여러 혼합기체에 대해 단순하고 간편하며 에너지 소비가 적다는 장점에 의해 기체분리에 효과적이고 응용성있는 공정으로 대두되고 있는데, 그 중에서도 분리막의 투과도(Permeability)와 선택도(Selectivity)를 동시에 높일수 있는 새로운 막재료의 개발에 관한 연구가 활발히 진행되고 있다. 이를 위해 고분자 구조를 화학적으로 변화시키는데, 이 경우에는 고분자의 구조 변화와 투과특성간의 관계를 밝히는 것이 매우 중요하다.

• Journal of Korean Society of Environmental Engineers
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• v.33 no.4
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• pp.251-257
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• 2011

In the present study, a 3-dimensional (3D) numerical model was developed to mimic the micro porous structure of a geological $CO_2$ storage reservoir. Especially, 3D modeling technique assigning random pore size to a 3D micro porous structure was devised. Numerical method using CFD (computational fluid dynamics) was applied for the 3D micro porous structure to calculate supercritical $CO_2$ flow field. The three different configurations of 3D micro porous model were designed and their flow fields were calculated. For the physical conditions of $CO_2$ flow, temperature and pressure were set up equivalent to geological underground condition where $CO_2$ fluid was stored. From the results, the characteristics of the supercritical $CO_2$ flow fields were scrutinized and the influence of the micro pore configuration on the flow field was investigated. In particular, the pressure difference and consequent $CO_2$ permeability were calculated and compared with increasing $CO_2$ flow rate.

• KSBB Journal
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• v.18 no.5
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• pp.385-392
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• 2003

Biodegradable poly (L-lactide) (L-PLA) solution in methylene chloride was precipitated into microparticles by using supercritical carbon dioxide modified with polar cosolvents. The effects of the amount of polar cosolvents, solution concentration, temperature, and solution flow rate on the formation of microparticles were investigated. The mean particle size was found to increase with the increase of solution concentration and flow rate. It was also observed that the particle size not only increases but the size distribution also becomes less uniform as the temperature increases. The percent recovery of microparticles was found to be 30∼40% at all experimental conditions. The supercritical carbon dioxide modified with methanol and ethanol was employed to enhance the recovery, resulting in significant improvement up to about 80 and 70%, for methanol and ethanol, respectively. Furthermore, the mean diameter of L-PLA microparticles was found to be less than 1 $\mu\textrm{m}$ for both cosolvents.

• Food Science and Preservation
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• v.11 no.2
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• pp.246-249
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• 2004

This study was conducted to evaluate the inhibition efficacy of high CO$_2$ atmosphere (35, 60, and 100% ${\times}$ 24, 48, and 72 h) on growth of Botrytis cinerea in vitro in order to offer sterilizing method of horticultural crops including peach fruits. Botrytis cinerea was isolated from a naturally infected peach fruits. Growth of the fungus at 25$^{\circ}C$ declined with increased CO$_2$ concentration and treatment duration. Especially, 100% CO$_2$ provided completely inhibition effect of growth of the fungus for 72 h. After removal of high CO$_2$ condition, however, the fungus showed normal growth speed. The growth of fungus at low temperature was completely inhibited temporarily by short-term 100% CO$_2$ treatment, but resumed right after transferring to normal atmosphere at 25$^{\circ}C$.

• Journal of the Korean Recycled Construction Resources Institute
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• v.8 no.2
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• pp.153-160
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• 2020

In this study, the optimum ratio of soil-cement was derived to utilize carbon capture minerals(CCM) as soil-cement for deep mixing method, quality characteristics of soil-cement mixed with carbon capture minerals were evaluated. The CCM is generated in the form of a slurry, and as a result of evaluating water content, it was found to be about 50%. Accordingly, the water content of CCM was removed in the unit water of Soil-cement mix. As a result of field mixing of soil-cement using CCM on field soil, it showed that the design allowable bearing capacity was satisfied by showing 3.0MPa or more as of 28 days of age. As a result of the hazard verification of carbon capture minerals, 0.055mg/L of Cu was detected, but satisfies the acceptance criteria, and no other harmful substances were eluted.

• Clean Technology
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• v.24 no.4
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• pp.287-292
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• 2018

Effect of physical property of activated carbon on its carbon dioxide adsorption was investigated for the effective control of carbon dioxide. Pinewood sawdust and coal were used as raw materials of activated carbon. Specific surface area, micropore volume and mesopore volume of the prepared activated carbons were determined, respectively. The prepared activated carbons were analyzed for their adsorption capacity of carbon dioxide. The adsorption capacity was then presented with respect to the surface area, micropore volume and mesopore volume, respectively. As a result, the specific surface area and micropore volume of both pinewood and coal activated carbon were highly related to its carbon dioxide capacity. Its mesopore volume hardly affected its carbon dioxide capacity. Preparation of activated carbon with high specific surface area and micropore volume was found to be critical to the effective control of carbon dioxide.