• Title/Summary/Keyword: carbon dioxide content

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Experimental Study on the Flue Gas Phenomena in Infrared Mobile Heaters (이동식 적외선 가스히터의 배기가스현상에 대한 실험적 연구)

  • 김영규;류근준
    • Journal of the Korean Society of Safety
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    • v.11 no.3
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    • pp.119-125
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    • 1996
  • The experimental work is performed to obtain content levels and characteristics of flue gas in infrared mobile heaters for butane gas with varying the chamber size and its room temperature. The results showed that the oxygen depletion sensor device is operated at 18.3% of oxygen content. And the relation of oxygen content and carbon dioxide content in an enclosed space show linear aspect, but the content rate of carbon monoxide occurs at random without the level of oxygen content and carbon dioxide content.

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Study on the Dissolution Characteristics of Liquid $CO_2$ Released by Fixed Pipeline (고정 파이프라인에서 분사된 액체 이산화탄소 용해특성 연구)

  • 김남진;김종보
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.16 no.9
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    • pp.863-871
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    • 2004
  • The use of fossil fuels like coal, oil and natural gases around the world causes an increase of the carbon dioxide content in the atmosphere. In order to reduce the concentration of the greenhouse gas, the idea of carbon dioxide sequestration in the ocean is proposed to be an effective mitigation strategy to counteract potential global warming due to the greenhouse effect. Therefore, in the present study, calculations of the dissolution behavior of carbon dioxide when liquid carbon dioxide is released at 1,000m and 1,500m in depth by fixed pipeline are performed. The results show that carbon dioxide droplets change to carbon dioxide bubbles in gas phase around 500m in depth, and the droplets are completely dissolved below 500 m in depth if the liquide carbon dioxide is released both at 1,000 m in depth with the initial diameter of 0.007m or less and at 1,500m in depth with the diameter of 0.011m or less.

Observations of Variations in Soil Organic Carbon and Carbon Dioxide in the Constructed Wetland at Goheung Bay (고흥만 인공습지의 토양유기탄소와 이산화탄소 변동 관측)

  • Kang, Dong-Hwan;Kim, Sung-Soo;Kwon, Byung-Hyuk;Kim, Il-Kyu
    • Journal of Fisheries and Marine Sciences Education
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    • v.20 no.1
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    • pp.58-67
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    • 2008
  • Seasonal variations in carbon dioxide in the air and soil organic carbon in the sediments were monitored at the constructed wetland formed by reclamation work at Goheung Bay. Sediment sampling in the constructed wetland and carbon dioxide measurement in the air were conducted on June 16 and August 23, 2007. Sediments in the constructed wetland were sampled at 11 different points (June 16) and 14 points (August 23), while carbon dioxide in the air was measured at 13 points (June 16) and 15 points (August 23). Water content and organic carbon in the sampled sediments were analyzed in the laboratory. Water content of the sediments was higher than that of general soil, and the variation between June and August was not evident. The amounts of organic carbons in the sediments sampled on August 23 were higher than those sampled on June 16. Also, there was more organic carbon in the sediments sampled at the field of reeds than in the pure wetland area. Daily maximum variation in carbon dioxide in the air was higher on June 16, but the amount of carbon dioxide in the air was greater on August 23. The results of the study suggest that organic carbon in the sediments and carbon dioxide in the air were greater in summer (August 23) than in spring season (June 16) in the constructed wetland at Goheung Bay.

Evaluation of the Utilization of Carbon Dioxide Microbubble Mixing Water for Mineral Carbonation of Cement Materials (시멘트 재료의 광물탄산화를 위한 이산화탄소 마이크로버블 배합수 활용성 평가)

  • Nam, Min-Seok;Park, Dong-Cheon
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2023.11a
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    • pp.205-206
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    • 2023
  • In this study, the characteristics of cement were analyzed using carbon dioxide microbubble water as a mixed water for mineral carbonation of cement materials. Carbon dioxide reacts with the calcium compound of cement to produce calcium carbonate and affects the initial strength improvement. Therefore, in this study, temperature, air content, thermal analysis, and compressive strength tests were conducted to confirm the reaction between cement materials and carbon dioxide. As a result of the measurement, the reaction between cement and carbon dioxide was confirmed in a specimen using carbon dioxide microbubble water as a mixed water, which affected the initial strength improvement.

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Effect of High Concentration Carbon Dioxide and Pre-Cooling Treated with Solid Carbon Dioxide on the Storability of Radish Sprout in MA Storage (고체 이산화탄소를 이용한 고농도 이산화탄소와 예냉 처리가 싹채소의 저장성에 미치는 영향)

  • Kang, Ho-Min;Choi, In-Lee;Kim, Il-Seop;Park, Keun-Woo
    • Journal of Bio-Environment Control
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    • v.18 no.3
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    • pp.285-290
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    • 2009
  • The solid carbon dioxide used for prolongation shelf life of radish sprout that was just 7days. The developed equipment for treated carbon dioxide consisted of solid carbon dioxide evaporated part and high carbon dioxide and low temperature treated part that can hold products. The inner temperature of equipment decreased temperature to below $5^{\circ}C$ from room temperature for 10minutes and carbon dioxide concentration increased to 80%. The radish sprouts treated 4 different conditions that was nontreated condition (control), solid carbon dioxide put into package (CO2-1), solid carbon dioxide treated before storage using the developed equipment (CO2-2), solid carbon dioxide treated before storage and during storage, and sprout packaged with solid carbon dioxide (CO2-3). These radish sprout packaged with $25{\mu}m$ ceramic film stored at $8^{\circ}C$. The high carbon dioxide treatment did not affect the fresh weight loss. The carbon dioxide and oxygen content in package changed 40% and 10%, respectively in CO2-1 and CO2-2 at 1day after treatments. But carbon dioxide content of all treatments was decreased to 5% and stabilized. The high carbon dioxide showed the effect of reduction ethylene production, but did not affect to visual quality and offodor.

Analysis of Carbon Emissions from Combustion of Three Arbor in Youngdong Area (영동지역 교목 3수종 생엽의 연소에 따른 탄소배출량 분석)

  • Park, Young-Ju;Lee, Hae-Pyeong
    • Journal of the Korean Society of Safety
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    • v.25 no.6
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    • pp.210-215
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    • 2010
  • In this study, when the forest fire occurred, in order to estimate greenhouse gas emissions, tree glow in Gangwon Youndong area, Juglans mandshurica, Alnus japonica, Acer palmatum of carbon dioxide and carbon monoxide emissions were about. Water content were measured before the experiment, Juglans mandshurica 196.24%, Alnus japonica 169.17% Acer palmatum 210.10% moisture content showed a big difference, Living leaves of Acer palmatum were a lot of moisture. Also, 50g weight of carbon dioxide on the Juglans mandshurica 53.3644g, Alnus japonica 49.4256g, was released about Acer palmatum 51.3394g, Juglans mandshurica living leaves were the most carbon dioxide emissions. Carbon monoxide emissions result, About weight 50g Juglans mandshurica 1.5329g, Alnus japonica 1.7189g, 2.5002g about Acer palmatum was released, Acer palmatum living leaves were the most carbon monoxide emissions.

Extraction of Active Compounds from Angelica gigas using Supercritical Carbon Dioxide and its Physiological Activity (초임계 이산화탄소를 이용한 참당귀 유효 성분의 추출 및 생리활성 효능)

  • Park, Su In;Heo, Soo Hyeon;Lee, Jinseo;Shin, Moon Sam
    • Journal of Convergence for Information Technology
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    • v.11 no.6
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    • pp.206-212
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    • 2021
  • This study aimed to maximize the efficacy of Angelica gigas by finding a more effective way to extract active compounds from Angelica gigas. After extracting Angelica gigas by hydrothermal, ethanol, and supercritical carbon dioxide extraction methods, analysis of decursin and decursinol angelate content, quantification of total polyphenol content, and evaluation of efficacy of antioxidant, whitening, and antibacterial were conducted. The content of decursin and decursinol angelate was very high at 38.65% of the supercritical carbon dioxide extract, and the total polyphenol content was high in the order of hydrothermal extract, ethanol extract and supercritical carbon dioxide extract, but the difference was relatively small. The antioxidant effects were consistent with the total polyphenol content, and the antibacterial effects were consistent with the decursin and decursinol angelate content. In other words, through this study, we found that the optimal method for extracting active compounds from Angelica gigas is the supercritical carbon dioxide extraction method.

Nitrogen Oxides Adsorbing Capacity of High Carbon Fly Ash Containing Cementitious Materials (탄소함량이 높은 플라이애쉬를 함유한 시멘트 페이스트의 질소산화물 흡착 성능)

  • Lee, Bo Yeon
    • Journal of the Architectural Institute of Korea Structure & Construction
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    • v.34 no.3
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    • pp.37-42
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    • 2018
  • The use of fly ash in construction materials is increasing worldwide due the various advantages of using it, such as to produce durable concrete, or to use less cement and thus lower carbon dioxide emissions. The quality of fly ash is often determined by loss on ignition value (LOI), where an upper limit of LOI is set in each country for quality control purpose. However, due to many reasons, production of high LOI fly ash is increasing that cannot be utilized in concrete, ending up in landfill. In this study, the effect of fly ash use in cementitious materials on nitrogen oxides adsorption is examined. In particular, the effect of using high LOI, and thus high carbon content fly ash on nitrogen oxides adsorption is investigated. The results suggest that the higher carbon content fly ash is related to higher nitrogen dioxide adsorption, although normal fly ash was also more effective in nitrogen dioxide adsorption than ordinary portland cement. Also, higher replacement rate of up to 40% of fly ash is beneficial for nitrogen dioxide adsorption. These results demonstrate that high carbon fly ash can be used as construction materials in an environmentally friendly way where strength requirement is low and where nitrogen oxides emissions are high.

Effects of Carbon Dioxide Application on the Plant Growth and Productivity of Strawberry in Greenhouse (시설내의 탄산가스 시용이 딸기의 생육 및 생산성에 미치는 영향)

  • Jung-Eun, Lee;Hyeon-Do, Kim;Gyu-Bin, Lee;Jum-Soon, Kang
    • Journal of Environmental Science International
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    • v.31 no.11
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    • pp.951-958
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    • 2022
  • The aim of this study was to determine the optimum level of carbon dioxide to maximize the quality and yields of strawberries cultivated in a greenhouse. Specifically, two strawberry cultivars, namely, 'Seolhyang' and 'Maehyang', were subjected to varying concentrations of carbon dioxide and patterns linked to their productivity were noted. Both cultivars showed improvements across various physical variables (i.e., leaf area, crown diameter, plant height, fresh weight, and dry weight) when carbon dioxide concentrations were at 1,500 ppm. The optimum carbon dioxide concentration for increased fruit yields and quality was 1,000 ppm. When carbon dioxide was at 1,000 ppm the yields of 'Seolhyang' and 'Maehyang' increased by 1.99 and 1.78 times, respectively, compared to control plants. The influence of carbon dioxide on fruit color was negligible. However, the carbon dioxide increased the sugar content and sugar-acid ratio of the experimental fruits compared to control plants. Specifically, the sugar-acid ratio, which is directly related to taste, was at its highest when the concentration of carbon dioxide was at 1,000 ppm (i.e., for both 'Seolhyang' and 'Maehyang'). Overall, the application of carbon dioxide culminated in improved yields and fruit quality for both cultivars of interest.

Experimental Study on CO2 Diffusivity in Cementitious Materials

  • Jung, Sang-Hwa;Lee, Myung-Kue;Kim, Jee-Sang
    • Corrosion Science and Technology
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    • v.4 no.2
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    • pp.69-74
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    • 2005
  • The carbonation of concrete is one of the major factors that cause durability problems in concrete structures. The rate of carbonation depends largely upon the diffusivity of carbon dioxide in concrete. The purpose of this study is to identify the diffusion coefficients of carbon dioxide for various concrete mixtures. To this end, several series of tests have been planned and conducted. The test results indicate that the diffusion coefficient increases with the increase of water-cement ratio. The diffusion coefficient decreases with the increase of relative humidity at the same water-cement ratio. The diffusion of carbon dioxide reached the steady state within about five hours after exposure. The content of aggregates also influences the diffusivity of carbon dioxide in concrete. It was found that the diffusion coefficient of cement paste is larger then that of concrete or mortar. The quantitative values of diffusivity of carbon dioxide in this study will allow more realistic assessment of carbonation depth in concrete structures.