• Clean Technology
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• v.20 no.4
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• pp.439-448
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• 2014

The potential mitigation of greenhouse gas (GHG) is studied in the Pohang steel industrial complex (PHSIC). The total GHG emission in 2010 is estimated to be in the range from 4,174,000 to 4,574,000 $tCO_2-eq$ in PHSIC. To meet the target proposed by the government, it is needed to reduce 552,000 $tCO_2-eq$ at minium by 2020. To estimate the potential amount of GHG reduction, the technologies used in the voluntary carbon reduction projects are applied to 51 companies which are subject to GHG target management. From the viewpoint of technological availability and payback period, the fuel conversion and waste heat recovery have an advantage in the short term with a possibility to reduce 160,000 $tCO_2-eq$. In the mid term, the thermal technologies in steel and iron industry have the potential to cut 229,000 $tCO_2-eq$, while the electrical technologies have the potential of 125,000 $tCO_2-eq$ reduction. The gap between the target GHG mitigation and potential reduction using the short and mid term technologies is about 38,000 $tCO_2-eq$, which should be compensated by the fundamental process innovation and the implementation of the most cutting-edge technologies including renewable energy.

• Korean Journal of Soil Science and Fertilizer
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• v.47 no.5
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• pp.374-380
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• 2014

To estimate greenhouse gas (GHG) emission, the inventory of rice cultivation at the farming without agricultural chemicals was established from farmers in Gunsan, Jeonbuk province in 2011~2012. The objectives of this study were to calculate carbon footprint and analyse the major factor of GHGs. To do this, we carried out a sensitivity analysis using the analyzed main factors of GHGs and estimated the mitigation potential of GHGs. Also we suggested agricultural methods to reduce GHGs that can be appled by farmers at this region. At the farming system without agricultural chemicals, carbon footprint of rice production unit of 1 kg was 2.15 kg $CO_2.-eq.kg^{-1}$. Although the amount of carbon dioxide ($CO_2$) emission was the largest among GHGs, methane ($CH_4$) emission had the highest contribution to carbon footprint on rice production system when it was converted to carbon dioxide equivalent ($CO_2-eq.$) multiplied by the global warming potential (GWP). Main source of $CO_2$ emission in the rice farming system without agricultural chemicals was combustion of fossil fuels used by agricultural machinery. Most of the $CH_4$ was emitted during rice cultivation practice and its major emission factor was flooded paddy field in anaerobic condition. Also, most of the $N_2O$ was emitted from rice cultivation process. Major sources of the $N_2O$ emission was application of fertilizer such as compound fertilizer. As a result of sensitivity analysis in energy consumption, diesel had the highest sensitivity among the energy inputs. With the reduction of diesel consumption by 10%, it was estimated that $CO_2$ potential reduction was about 2.0%. With reducing application rate of compound fertilizer by 10%, the potential reduction was calculated that $CO_2$ and $N_2O$ could be reduced by 0.5% and 0.9%, respectively. At the condition of 10% reduction of silicate and compost, $CO_2$ and $CH_4$ could be reduced by 1.5% and 1.6%, respectively. With 8 days more drainage than the ordinary practice, $CH_4$ emission could be reduced by about 4.5%. Drainage and diesel consumption were the main sources having the largest effect on the GHG reduction at the farming system without agricultural chemicals. Based on the above results, we suggest that no-tillage and midsummer drainage could be a method to decrease GHG emissions from rice production system.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2011.05a
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• pp.5-6
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• 2011

CO₂ reduction is the most urgent issue the world is facing. So, there should be a measure to reduce the CO₂ emission in construction industry which has more released CO₂ gas than other industries. CO₂ emission of building depend on using energy. Then efficient energy use process working efficiently at CO₂ reduction. Therefore In this study, author find the technical possibility of saving the building energy using the PCM which is able to control heat, storage heat and potential heat. So, it considered that apply to floor heating type which is major heating system of living space in Korea. And evaluate the Using possibility.

• Journal of Climate Change Research
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• v.4 no.3
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• pp.211-219
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• 2013

This study uses the LEAP model that is a long-term energy analysis model to analyze reduction potential on S city residential sector energy usage for greenhouse gas emission. Energy consumption of S-si in 2009 is consumed most in residential and commerce sector by 39.1%. Also, energy and greenhouse gas emission of residential sector is expected to increase due to increase of households. Therefore, greenhouse gas reduction measures are desperately required in residential sector. For this study recognizes energy consumption of S-si residential sector and has established reduction measure of S-si residential sector greenhouse gas through literature search on domestic and foreign climate change correspondence policies. Also, construction of greenhouse gas reduction potential by reduction measures through LEAP model. There were a total of 5 reduction measures scenarios is Reference Scenario, LED Lighting, Energy Alternative, Green Life Practice, and Total Reduction Measure. As a result, greenhouse gas emission of Light Emitting Diode Lightings by 2020 was $1,181.0thousand\;tonCO_2eq$, decrease of 6.1% compared to the Reference Scenario and Greenhouse gas emission of Energy Alternative by 2020 was $1,171.6thousand\;tonCO_2eq$, decrease of 6.8% compared to the Reference Scenario. Greenhouse gas emission of Green Life Practice by 2020 was $1,128.7thousand\;tonCO_2eq$, decrease of 10.2% compared to the Reference Scenario. For Total Reduction Measures by 2020 emission was $966.9thousand\;tonCO_2eq$, decrease 23.1% compared to Reference Scenario.

• Bulletin of the Korean Chemical Society
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• v.20 no.9
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• pp.1056-1060
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• 1999

New water soluble and highly electron deficient cobalt(II) tetrakis-(1,2,5,6-tertrafluoro-4-NN'N"-trimethyla-nilinium)-β-octabromoporphyrin [Co II (Br8TTFP)(Y)2] was synthesized and used for the electrocatalytic reduction of dioxygen. The first reduction of synthesized [Co II (Br8TTFP)(Y)2] involves one electron process to give metal centered [Co I (Br8TTFP)(Y)2]. The reduction of potential [E1/2 = -0.32 V] of [Co II (Br8TTFP)(Y)2] shifts positively 370 mV compared with that of [Co II (TTFP)(Y)2] due to the substituted bromide to β-pyrrole positions. The electrochemically reduced [Co I (Br8TTFP)(Y)2] binds dioxygen and catalytically reduces it to HOOH by 2e - transfer. Cyclic and hydrodynamic voltammetry at a glassy carbon electrode in dioxygen-saturated aqueous solutions are used to study the electrocatalytic pathway.

• Journal of Korean Society of Forest Science
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• v.97 no.5
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• pp.530-539
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• 2008

The study evaluates the greenhouse gas (GHG) reduction potential of paper recycling by paper industry in South Korea and determines the positive impact on global warming by conserving the world's forests through decreasing pulp wood use. South Korea is one of the leading countries in the world thai recycle papers with a collection rate of 71.8 percent and a recycling rate of 74.4 percent in 2005. Greenhouse gas emission reduction potential in terms of carbon dioxide ($CO_2$) equivalent from paper recycling was assessed scientifically by the use of Life Cycle Assessment (LCA). Three types of papers including newsprint, container-board, and white-board were used for assessment in this study. Results of this study indicate that $CO_2$ emission reduction potential of recycling paper varies according to its types and recycling rates. Greenhouse gas emission reduction factor of 0.74869 $tCO_2$ per ton of recycled paper was derived from this study. In applying this factor. it was found out that the South Korean paper industry reduced GHG emission of around 6,364,550 $tCO_2$ by recycling paper in 2005. With this. the country's paper industry could claim that by recycling in thai particular year. approximately $23.8million\;m^3$ of woods were not harvested and thus 212,500 ha of world's forests were estimated to be saved in that particular year. Overall. it could be concluded that the Korean paper industry was able to reduce $CO_2$ emission and was able to conserve world's forests by its high rates of paper recycling.

• Journal of the Korean Ceramic Society
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• v.55 no.4
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• pp.381-391
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• 2018

In this work, photocatalytic $CO_2$ reduction over a CdSe-graphene-$TiO_2$ nanocomposite has been studied. The obtained material was successfully fabricated via ultrasonic technique. The physical properties of the as-synthesized materials were characterized by some physical techniques. The $TiO_2$ and CdSe dispersed graphene nanocomposite showed excellent results of strong reduction rates of $CO_2$ compared to the results of bare $TiO_2$ and binary CdSe-graphene. An outstanding point of the combination of CdSe-$TiO_2$ and graphene appeared in the form of great photocatalytic reduction capability of $CO_2$. The photocatalytic activity of the asfabricated composite was tested by surveying for the photoreduction of $CO_2$ to alcohol under UV and visible light irradiation, and the obtained results imply that the as-prepared CdSe-graphene-$TiO_2$ nanocomposite is promising to become a potential candidate for the photocatalytic $CO_2$ reduction.

• Bulletin of the Korean Chemical Society
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• v.19 no.7
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• pp.754-760
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• 1998

It was found that the adsorption of a cobalt(III) complex with a macrocyclic ligand, C-meso-5,7,7,12,14,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane (hmc), was induced on a glassy carbon electrode by heavily oxidizing the electrode surface. Adsorption properties are discussed. The glassy carbon electrode with the adsorbed complex was employed to see the catalytic activities for the electro-reduction of O2. In the presence of oxygen, reduction of (hmc)Co3+ showed two cathodic waves in cyclic voltammetry. Compared to the edge plane graphite electrode at which two cathodic waves were also observed in a previous study, catalytic reduction of O2 occurred in the potential region of the first wave while it happened in the second wave region with the other electrode. A rotating disk electrode after the same treatment was employed to study the mechanism of the O2 reduction and two-electron reduction of O2 was observed. The difference from the previous results was explained by the different reactivity of the (hmc)CoOOH2+ intermediate, which is produced after the two electron reduction of (hmc)Co3+ in the presence of O2.

• Bulletin of the Korean Chemical Society
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• v.19 no.2
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• pp.183-188
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• 1998

Incorporation of metalloporphyrins into polypyrrole (PPy) film was achieved either by electropolymerization of pyrrole in the presence of metal-tetra(sulfonatophenyl)porphyrin anion (MTSPP, M=Co, Fe) or by metalizing hydrogenated tetra(4-sulfonatophenyl)porphyrin anion (H2TSPP) doped into PPy through ion-exchange. Electrochemical reduction of oxygen on the PPy doped with metallo porphyrin (PPy-MTSPP) was studied in acidic and basic solutions. Oxygen reduction on PPy-MTSPP electrodes appeared to proceed through a 4-electron pathway as well as a 2-electron path. In acidic solutions, the overpotential for O2 reduction on PPy-CoTSPP electrode was smaller than that on gold by about 0.2 V. In basic solutions the overpotential of the PPy-CoTSPP electrode in the activation range was close to those of Au and Pt. The limiting current was close to that of Au. However, polypyrrole doped with cobalt-tetra(sulfonatophenyl)porphyrin anion (PPy-CoTSPP) or with iron-tetra(sulfonatophenyl)porphyrin anion (PPy-FeTSPP) was found to have limited potential windows at high temperatures (above 50 ℃), and hence the electrode could not be held at the oxygen reduction potentials in basic solutions (pH 13) without degradation of the polymer.

• Bulletin of the Korean Chemical Society
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• v.19 no.4
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• pp.417-422
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• 1998

The electrocatalytic reduction of molecular oxygen was investigated with a Co(II)-glyoxal bis(2-hydroxyanil) complex coated-glassy carbon (GC) electrode in aqueous media. The reduction of $O_2$ at the modified electrode was an irreversible and diffusion-controlled reaction. The complex coated-GC electrode demonstrated an excellent electrocatalytic effect for $O_2$ reduction in an acetate buffer solution of pH 3.2. The coated electrode made the $O_2$ reduction potential shift of 60-510 mV in a positive direction compared to the bare GC electrode depending on pH. The Co(II)-glyoxal bis(2-hydroxyanil) coated electrode converted about 51% of the $O_2$ to $H_2O_2$ via a two-electron reduction pathway, with the balance converted to H_2O$.