• Asian Journal of Atmospheric Environment
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• v.4 no.3
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• pp.166-176
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• 2010

In this research, the environmental behavior of carbon dioxide ($CO_2$) was investigated in a mountainous site in the proximity of a highly industrialized megacity, Seoul, Korea. The concentration data of $CO_2$ monitored routinely at hourly intervals at Mt. Gwan-Ak (GA), Seoul, Korea throughout 2009 were analyzed in several respects. The mean $CO_2$ value was $405{\pm}12.1$ ppm (median=403 ppm) with a range of 344 to 508 ppm (N=8548). The analysis of its seasonal trend indicated that the $CO_2$ levels peaked in the winter but reached a minimum in fall. If the short-term trend is analyzed, the $CO_2$ values generally peaked during daytime along with the presence of two shoulders; this is suspected to be indicative of strong man-made effects (e.g., traffic activities). It is seen that the general patterns of $CO_2$ distribution in this study area are highly comparable to those typically found in urban areas with strong signals of anthropogenic activities.

• Journal of Sensor Science and Technology
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• v.30 no.6
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• pp.456-460
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• 2021

In this study, a Non-Dispersive Infrared (NDIR) Carbon Dioxide (CO₂) sensor with an externally exposed optical cavity is proposed for improving sensitivity. NDIR CO₂ sensors with high performance must use a lamp-type infrared (IR) source with a strong IR intensity. However, a lamp-type IR source generates high thermal energy that induces thermal noise, interfering with the accuracy of the CO₂ concentration measure. To solve this problem, the optical cavity of the NDIR CO₂ sensor is exposed to quickly dissipate heat. As a result, the proposed NDIR CO₂ sensor has a shorter warm-up time and a higher sensitivity compared to the conventional NDIR CO₂ sensor.

• Journal of the Korean Society for Railway
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• v.14 no.1
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• pp.1-5
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• 2011

High concentration of carbon dioxide at subway cabin is one of the serious environmental concerns because carbon dioxide causes drowsiness, headache, and nervelessness of passengers. Ministry of Environment set a guideline for indoor carbon dioxide levels in train or subway in 2007. In this study, a carbon dioxide removal system for subway cabin was developed and tested using a test subway cabin. Various types of modified zeolites were used as the adsorbent of carbon dioxide. The tested zeolites were applied to the subway cabin, and showed high potential to lower the indoor $CO_2$ level.

• Bulletin of the Korean Chemical Society
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• v.35 no.1
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• pp.57-61
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• 2014

In this study, carbon aerogel (CA) was synthesized using a soft-template method, and the optimum conditions for the adsorption of carbon dioxide ($CO_2$) by the carbon aerogel were evaluated by controlling the activation temperature. KOH was used as the activation agent at a KOH/CA activation ratio of 4:1. Three types of activated CAs were synthesized at activation temperatures of $800^{\circ}C$(CA-K-800), $900^{\circ}C$(CA-K-900), and $1000^{\circ}C$(CA-K-1000), and their surface and pore characteristics along with the $CO_2$ adsorption characteristics were examined. The results showed that with the increase in activation temperature from 800 to $900^{\circ}C$, the total pore volume and specific surface area sharply increased from 1.2165 to $1.2500cm^3/g$ and 1281 to $1526m^2/g$, respectively. However, the values for both these parameters decreased at temperatures above $1000^{\circ}C$. The best $CO_2$ adsorption capacity of 10.9 wt % was obtained for the CA-K-900 sample at 298 K and 1 bar. This result highlights the importance of the structural and textural characteristics of the carbon aerogel, prepared at different activation temperatures on $CO_2$ adsorption behaviors.

• Journal of Construction Engineering and Project Management
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• v.1 no.1
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• pp.11-17
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• 2011

According to the United Nations Framework Convention on Climate Change (UNFCCC), many countries around the world have been concerned with reducing Greenhouse Gas (GHG) emissions. Reducing the level of building energy consumption is particularly important in bringing GHG down. Because of this, many countries including the US and the EU are enforcing energy-related policies. However, these policies are focused on management of single types of buildings such as public buildings and office buildings, instead of management on a national level. Thus, although various policies have been enforced in many countries, $CO_2$ management on a national level is still not an area of focus. Therefore, this study proposed a community-based $CO_2$ management process that allows government-led GHG management. The minimum unit of the community in this study is a plot, and the process consists of three steps. First, the current condition of the GHG emission was identified by plot. Second, based on the identified results, the GHG emission reduction target was distributed per plot by reflecting the weighted value according to (i) the target $CO_2$ reduction in the buildings in the standard year, (ii) region, and (iii) building usage and size. Finally, to achieve the allocated target reduction, building energy management was executed according to the properties of the building located on each plot. It can be expected that the proposed community-based $CO_2$ management process will enable government-level GHG management, through which environment-friendly building construction can be promoted.

• International conference on construction engineering and project management
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• 2011.02a
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• pp.262-268
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• 2011

According to the United Nations Framework Convention on Climate Change (UNFCCC), many countries around the world have been concerned with reducing Greenhouse Gas (GHG) emissions. Reducing the level of building energy consumption is particularly important in bringing GHG down. Because of this, many countries including the US and the EU are enforcing energy-related policies. However, these policies are focused on management of single types of buildings such as public buildings and office buildings, instead of management on a national level. Thus, although various policies have been enforced in many countries, CO₂ management on a national level is still not an area of focus. Therefore, this study proposed a community-based CO₂ management process that allows government-led GHG management. The minimum unit of the community in this study is a plot, and the process consists of three steps. First, the current condition of the GHG emission was identified by plot. Second, based on the identified results, the GHG emission reduction target was distributed per plot by reflecting the weighted value according to (i) the target CO₂ reduction in the buildings in the standard year, (ii) region, and (iii) building usage and size. Finally, to achieve the allocated target reduction, building energy management was executed according to the properties of the building located on each plot. It can be expected that the proposed community-based CO₂ management process will enable government-level GHG management, through which environment-friendly building construction can be promoted.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.11
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• pp.5357-5364
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• 2011

The objective of this study is development of carbon recycle technology which convert carbon dioxide captured from flue gas to carbon monoxide or carbon and reuse in industrial fields. Since carbon dioxide is very stable and difficult to decompose, metal oxide was used as activation agent for the decomposition of carbon dioxide at low temperature. Metal oxides which convert $CO_2$ to CO or carbon were prepared using Ba-ferrite by solid and hydrothermal synthesis. TPR/TPO and TGA were used in this study. The results of TPR by H2 and TPO by $CO_2$ showed that Ba-ferrite powders synthesized by hydrothermal method were better than those by solid method. TGA showed contrary results that reduction of Ba-ferrite powders synthesized using solid method by $H_2$ was 21.96 wt%, oxidation by $CO_2$ was 21.24 wt% and 96.72 wt% of $CO_2$ decomposition efficiency showing excellent oxidation-reduction characteristics at $500^{\circ}C$.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.24 no.3
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• pp.149-157
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• 2018

Low density polyethylene (LDPE) has been researched in many industrial applications, and LDPE/zeolite 4A composites has been extensively studied for many applications such as microporous, breathable film and so on. LDPE/zeolite composite have a great potential for carbon dioxide adsorption film due to its high adsorption ability. In this study, LDPE/zeolite 4A composites with various contents were prepared by melt mixing process, and co-extrusion process was applied to develop a $CO_2$ adsorption conventional film and foamed film. The thermal, rheological, mechanical, physical and morphological properties of composite films has been characterized, and $CO_2$ adsorption of the composite films evaluated by thermogravimetric analysis (TGA) and the performance was found to be about 18 cc/g at 30.9 wt% of the zeolite content.

• Korean Chemical Engineering Research
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• v.47 no.4
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• pp.410-417
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• 2009

Carbon dioxide was absorbed into GMA solution in a stirred flat cell using mesoporous catalyst Imidazole-CP-MS41, which was synthesized by CP-MCM41 with imidazole. Experiments were carried out at a batch-type absorber with different conditions, varying reaction temperature, concentration of GMA, solvent but maintaining 50 rpm of agitation speed and 2 g of catalyst. Absorption rate of $CO_2$ was used to obtain the kinetics based on the film theory using zwitterion mechanism with 2 elementary reaction and the kinetics were correlated with the solubility parameter of the solvents.

• Journal of Environmental Science International
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• v.16 no.3
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• pp.287-297
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• 2007

Increasing carbon dioxide emissions from fossil fuel use and land-use change has been perturbing the balanced global carbon cycle and changing the carbon distribution among the atmosphere, the terrestrial biosphere, the soil, and the ocean. SGCM(Simple Global Carbon Model) was used to simulate global carbon cycle for the IPCC emissions scenarios, which was six future carbon dioxide emissions from fossil fuel use and land-use change set by IPCC(Intergovernmental Panel on Climate Change). Atmospheric $CO_2$ concentrations for four scenarios were simulated to continuously increase to $600{\sim}1050ppm$ by the year 2100, while those for the other two scenarios to stabilize at $400{\sim}600ppm$. The characteristics of these two $CO_2$-stabilized scenarios are to suppress emissions below $12{\sim}13$ Gt C/yr by tile year 2050 and then to decrease emissions up to 5 Gt C/yr by the year 2100, which is lower than the current emissions of $6.3{\pm}0.4$ Gt C/yr. The amount of carbon in the atmosphere was simulated to continuously increase for four scenarios, while to increase by the year $2050{\sim}2070$ and then decrease by the year 2100 for the other two scenarios which were $CO_2$-stabilized scenarios. Even though the six emission scenarios showed different simulation results, overall patterns were such similar that the amount of carbon was in the terrestrial biosphere to decrease first several decades and then increase, while in the soil and the ocean to continuously increase. The ratio of carbon partitioning to tile atmosphere for the accumulated total emissions was higher for tile emission scenario having higher atmospheric $CO_2$, however that was decreasing as time elapsed. The terrestrial biosphere and the soil showed reverse pattern to the atmosphere.