• Journal of Korean Society of Environmental Engineers
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• v.31 no.8
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• pp.679-689
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• 2009

Light olefins are very important hydrocarbons widely used as the raw materials of the most petrochemicals including plastics and medicines. In addition, the nation's olefin production capacity is regarded as one of the key indicators to predict the nation's economic scale and growth. Steam cracking of naphtha (or called "NCC (Naphtha Cracking Center) technology"), the traditional process to produce light olefins, is one of the most consuming energy processes among the chemical industries. Therefore, this process causes tremendous $CO_2$ emission. To reduce the energy consumption and $CO_2$ emission from NCC process, the present paper, firstly, investigates and analyses some alternative technologies which can be potentially substituted for traditional process. Secondly, applying the alternative technologies to NCC process, their effects such as energy savings, $CO_2$ emission reduction and CER (Certified Emission Reduction) were estimated. It is found that the advanced NCC process can reduce approximately 35% of SEC (Specific Energy Consumption) of traditional NCC process. This effect can lead to the reduction of 3.3 million tons of $CO_2$ and the acquisition of the 128 billion won of CER per year. Catalytic cracking of naphtha technology, which is other alternative processes, can save up to approximately 40% of SEC of traditional NCC process. This value equates to the 3.8 million tons of $CO_2$ mitigation and 147 billion won of CER per year.

• Journal of Electrochemical Science and Technology
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• v.6 no.3
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• pp.106-110
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• 2015

This study investigates Cu(II) complexes of cyclam, propylene cross-bridged cyclam (PCB-cyclam), and propylene cross-bridged cyclam diacetate (PCB-TE2A) as homogeneous electrocatalysts for CO₂ reduction in comparison with Ni(II)-cyclam. It is found that Cu(II)-cyclam can catalyze CO₂ reduction at the potential close to its thermodynamic value (0.75 V vs. Ag/AgCl) in tris-HCl buffer (pH 8.45) on a glassy carbon electrode. Cu(II)-cyclam, however, suffers from severe demetalation due to the insufficient stability of Cu(I)-cyclam. Cu(II)-PCB-cyclam and Cu(II)-PCB-TE2A are revealed to exhibit much less demetalation behavior, but poor CO₂ reduction activities as well. The inferior electrocatalytic ability of Cu(II)-PCB-cyclam is ascribed to its redox potential that is too high for CO₂ reduction, and that of Cu(II)-PCB-TE2A to the steric hindrance preventing facile contact with CO₂ molecules. This study suggests that in addition to the redox potential and chemical stability, the stereochemical aspect has to be considered in designing efficient electrocatalysts for CO₂ reduction.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.44 no.7
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• pp.603-610
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• 2016

This paper describes experimental results about emission and NOx reduction of dilution effect (Nitrogen and carbon dioxide) about various fuel compositions of synthetic natural gas (SNG). Combustion experiment was performed to investigate the combustion characteristics for SNG with various hydrogen ratio in SNG, heat input and equivalence ratio in a partially premixed model gas turbine combustor. NOx emission was similar to each hydrogen ratio and flame characteristics was investigated from OH chemiluminescence images. There was a singularity of CO emission in stoichiometric condition and it can be identified using OH chemiluminescence intensity. In addition, dilution effect was studied in using nitrogen and carbon dioxide as diluent to reduce the NOx emission. Carbon dioxide diluent was more effective to NOx reduction than nitrogen diluent because of its high diluent specific heat and its heat capacity.

• Korean Journal of Food Science and Technology
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• v.30 no.3
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• pp.574-580
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• 1998

The technical feasibility of removing cholesterol from milk fat by supercritical carbon dioxide $(SC-CO_2)$ extraction followed by adsorption on different adsorbents and of fractionating milk fat into different fatty acid composition at $40^{\circ}C/276$ bar was investigated. Cholesterol could be selectively removed from milk fat by adsorption on a typical commercial florisil with $SC-CO_2$ extraction. Lower weight ratio of milk fat feed to florisil showed higher reduction of cholesterol, but gave lower yield in the milk fat fractions. The effective capacity of florisil for removing cholesterol from milk fat was 2.0g/g, which is the ratio of the fat feed to the adsorbent for 89% cholesterol reduction with a fat yield of 57.5%. Fatty acid composition showed higher short-chain and lower unsaturated long-chain fatty acids in the extracted fractions. Milk fat fractionation method by supercritical fluid extraction in coupled with adsorption would appear suitable for removing undesirable ingredients such as cholesterol and for enriching short-chain fatty acids in the fractions.

• KEPCO Journal on Electric Power and Energy
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• v.2 no.4
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• pp.517-523
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• 2016

South Korea is the 8th biggest greenhouse gas emitter in the world due to its phenomenal economic growth based on manufacturing, and it is ranked first among OECD members for the rate of increase in emissions. Thus, the Korea government has voluntarily presented a reduction target and demonstrated global leadership. For the reduction of nation's GHG emission, importance of CCU(Carbon Capture and Utilization) along with CCS(Carbon Capture and Storage) technology development is increased. CCU technology is $CO_2$ utilization technology for the usage of $CO_2$ from flue gas and it can create a new economic value while reducing $CO_2$ emission. Therefore, with continued technology development, the number of application of CCU technology is increasing globally.

• Journal of the Korean Recycled Construction Resources Institute
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• v.11 no.4
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• pp.493-500
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• 2023

The use of TiO₂ photocatalyst in the production of concrete blocks for the purpose of nitrogen oxide reduction is an issue of controversy due to the conflicting evidence on its effectiveness. Efforts have been made to reduce the level of nitrogen oxides in the environment by using of titanium dioxide (TiO₂). This study examined the effect of incorporating activated carbon into concrete blocks on the reduction of nitrogen oxides released into the atmosphere and the durability of the blocks. The efficiency of photocatalyst was enhanced through the addition of a surrounding conductive substance. The addition of activated carbon resulted in a significant increase in the electrical conductivity of photocatalytic blocks and improved durability. The cement mixture using 5 % TiO₂ and 15 % activated carbon exhibited the optimal mixing ratio for the purpose of nitrogen oxide removal. The effect of the addition of conductive carbon to the photocatalytic blocks was discussed with the results of conductivity, flexural and comprssive strength and nitrogen oxide removal test. The relationship between the addition of conductive carbon to the photocatalytic blocks and its resulting effects have been studied by several tests, including conductivity, flexural and compressive strength, and nitrogen oxide removal.

• Korean Journal of Poultry Science
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• v.31 no.4
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• pp.213-219
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• 2004

The objectives of this study were to investigate the effect of applying three different chemical additives to the litter (rice hull) on broiler performance, ammonia and carbon dioxide gas reduction in a poultry house at 6 weeks. A total of 96 broiler chicks (6 treatments$\times$4 replicates$\times$4 birds) were fed the experimental diets for 6 weeks. The chemical additives were applies as a top dressing to the litter at a rate of 200 g ferrous sulfate $(FeSO_4)$, 200 g aluminum chloride $(AlCl_3)$ + 50 g calcium carbonate $(CaCO_3)$ and 20 g potassium permanganate $(KMnO_4)$ per kg litter, while the control group did not have the three different chemicals added to the litter. There were no significant differences in broiler performance between the three chemical additives and control group. $FeSO_4\;and\;AlCl_3\;+\;CaCO_3$ treatment reduced ammonia production from the litter at 6 weeks by as much as 91 and $53\%$, respectively (P<0.05). $KMnO_4$ treatment decreased ammonia production at 6 weeks up to $69\%$ compared to the controls (P<0.05). Poultry litter amended with $AlCl_3\;+\;CaCO_3\;and\;KMnO_4$ also caused a decrease (P<0.01) in carbon dioxide productions at 6 weeks (59 and $65\%$, respectively). In conclusion, although broiler performance was not affected by the three chemical additives and control group, these results indicate that $FeSO_4,\;AlCl_3\;+\;CaCO_3\;and\;KMnO_4$ application to litter in a poultry house resulted in a significant reduction in atmospheric ammonia and carbon dioxide gas.

• 한국연소학회:학술대회논문집
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• 2014.11a
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• pp.37-40
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• 2014

Capturing the carbon dioxide emitted from coal-fired power plants will be necessary if targeted reduction in carbon emissions is to be achieved. Modelling and simulation are the base for optimal operation and control in thermal power plant and also play an important role in energy savings. This study aims to analyze the performance of supercritical coal fired power plant through steady and dynamic simulation using a commercial software gCCS. A whole power plant has been modeled and validated with design data of 500 MWe power plant, base and part load operations of the plant were also evaluated, consequently it had been proven that the simulated result had a good agreement with actual operating data. In addition, the effect of co-firng on the plant efficiency and flue gases were investigated using gCCS simulator.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.26 no.1
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• pp.25-31
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• 2020

Recently, applications of biomass-based plastics have increased according to the eco-friendly policy of the reduction of carbon dioxide emissions in domestic and foreign government. In this study, a paper plastic composite was produced by compounding polypropylene and micronized paper powder that was prepared using dry pulverization technology. Subsequently, the specimen of paper plastic was verified with mechanical properties, formability and product safety test to confirm the suitable packaging materials for food packaging. Paper plastics showed slightly lower mechanical properties than currently commercialized PP composites. However, paper plastics are valuable materials as environmentally friendly carbon-reducing material because of high biocarbon content, light weight features and applicability of existing manufacturing machines or system.

• Spatial Information Research
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• v.22 no.2
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• pp.1-9
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• 2014

UN-REDD (United Nations programme on Reducing Emissions from Deforestation and forest Degradation in Developing Countries) and AR-CDM (Afforestation/Reforestation-Clean Development Mechanism) is currently being emerged as one of important mechanism to reduce carbon dioxide in relation to the deforestation. Discussion on North Korea as UN-REDD/AR-CDM project target continues with a view to preventing deforestation and to securing CER(certified emission reduction) for South Korea. The forests in Mt. Baekdu are degraded, deforestation is occurred, nevertheless, portion of forested area is still high, where both REDD and AR-CDM investment potential are quite high. Accordingly, this study is intended to explore a simultaneous registration potential to UNREDD/AR-CDM for Mt. Baekdu although separate registration to UN-REDD or AR-CDM has already gained worldwide recognition as a typical method in the process of GHG (Greenhouse Gas) reduction project. The results indicate that selecting UN-REDD or AR-CDM in accordance with sub-watershed forest condition could capture 53.2% more carbon dioxide than REDD alone and 21.9% more than AR-CDM alone. It is anticipated that this research output could be used as a realistic evidence to introduce carbon sequestering project in accordance with sub-watershed forest condition.