• Journal of Mechanical Science and Technology
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• v.18 no.12
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• pp.2303-2309
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• 2004

Flue gas recirculation (FGR) is a method widely adopted to control NOx in combustion system. The recirculated flue gas decreases flame temperature and reaction rate, resulting in the decrease in thermal NO production. Recently, it has been demonstrated that the recirculated flue gas in fuel stream, that is, the fuel induced recirculation (FIR), could enhance a much improved reduction in NOx per unit mass of recirculated gas, as compared to the conventional FGR in air. In the present study, the effect of FGR/FIR methods on NOx reduction in turbulent swirl flames by using N$_2$ and CO$_2$ as diluent gases to simulate flue gases. Results show that CO$_2$ dilution is more effective in NO reduction because of large temperature drop due to the larger specific heat of CO$_2$ compared to N$_2$ and FIR is more effective to reduce NO emission than FGR when the same recirculation ratio of dilution gas is used.

• Journal of the Architectural Institute of Korea Structure & Construction
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• v.34 no.10
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• pp.37-44
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• 2018

In this study, the effects of considering hourly metabolic rate variations for predicted mean vote (PMV) control on the heating and cooling energy and greenhouse gas emission were investigated. The case adopting PMV control taking the hourly metabolic rate into account was comparatively analyzed against the conventional dry-bulb air temperature control, using a detailed simulation technique. Under the assumption that all the apartments in Korea adopt the PMV control incorporating real-time metabolic rate measurements, nationwide reductions of primary energy and greenhouse gas emission were analyzed. As a result, PMV control considering hourly metabolic rate variations is expected to reduce national primary energy by 6.2% compared to conventional dry-bulb air temperature control, corresponding to reduction of 10,342 GWh. In addition, it turned out that 6.6% of tCO2 emission can be reduced by adopting PMV control, corresponding to nationwide reduction of greenhouse gas emission by approximately 1,720,000 tCO2.

• Journal of Mechanical Science and Technology
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• v.19 no.6
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• pp.1358-1365
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• 2005

Flue gas recirculation (FGR) is widely adopted to control NO emission in combustion systems. Recirculated flue gas decreases flame temperature and reaction rate, resulting in the decrease in thermal NO production. Recently, it has been demonstrated that the recirculated flue gas in fuel stream, that is, the fuel induced recirculation (FIR), could enhance much improved reduction in NO per unit mass of recirculated gas, as compared to conventional FGR in air. In the present study, the effect of dilution methods in air and fuel sides on NO reduction has been investigated numerically by using $N_2$ and $CO_2$ as diluent gases to simulate flue gases. Counterflow diffusion flames were studied in conjunction with the laminar flamelet model of turbulent flames. Results showed that $CO_2$ dilution was more effective in NO reduction because of large temperature drop due to the larger specific heat of $CO_2$ compared to $N_2$. Fuel dilution was more effective in reducing NO emission than air dilution when the same recirculation ratio of dilution gas was used by the increase in the nozzle exit velocity, thereby the stretch rate, with dilution gas added to fuel side.

• Journal of Environmental Impact Assessment
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• v.8 no.4
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• pp.59-72
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• 1999

The purpose of the study is to propose the concrete and realistic alternative measures for $CO_2$ emission reduction on commercial sector. To achieve the purpose, this study adopted AIM/KOREA simulation model modified from AIM(Asia-Pacific Integrated Model) originally developed by Japan National Environmental Research Institute. The results of simulation demonstrate that the $CO_2$ emission from the commercial sector in 1995 was estimated 864 million TC(tons of carbon); however, according to the base scenario, $CO_2$ emission in 2020 is expected to be increased to 1,872 million TC, which is 2.17 times greater than that in 1995. In order to mitigate the ever-increasing $CO_2$ emission, the results of AIM/KOREA simulations under various scenarios showed that the 30-thousand-won carbon tax scenario does not successfully motivate the selection of advanced technology; however, with the 300-thousand-won carbon tax, a substantial amount of $CO_2$ emission reduction by 1.69 million TC from the BaU((Business-as-Usual)scenario is expected to be achieved by year 2020. Such substantial reduction of $CO_2$ emission under the 300-thoudsand-won carbon tax scenario is due to the introduction of advanced technology, such as use of condensing boilers, forced by heavier carbon tax. Under the scenario that presumes the maximum introduction of gas-burning industrial appliances, an 2.66 million TC of $CO_2$ reduction was expected. The results of this study suggest that the $CO_2$ emission reduction measures can be interpreted in many different views. However, if people and industries are fully aware of the economic benefit of energy saving, a certain level of $CO_2$ reduction by a successful introduction of advanced energy saving technology appears to be achieved without carbon tax or subsidies.

• KIEAE Journal
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• v.11 no.2
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• pp.67-74
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• 2011

Recently environmental regulations like the Kyoto Protocol, adopted in 1997, required the reduction of the greenhouse gas of 5.2% up to 1990's emissions and 13th General Assembly in 2007, held in Bali of India, have agreed to duty reduction even in developing countries in 2013. Korean government needs research on climate change and greenhouse gas management, such as carbon emissions calculation system and the introduction of greenhouse gas reduction program. Using Top-Down approach with method of IPCC, greenhouse gas emissions from energy, transportation, agriculture, land use and forest, and waste was calculated. Total amount from Shiheung-City in 2007 was about 3,299.581 tons of greenhouse gas $CO_2$. By sectors, the total greenhouse gas emissions in the energy sector mostly accounted for 78 percent, 12 percent from transportation, 6 percent of waste, the landuse/forest sector, 4% of the greenhouse gas emissions. Approximately 5,401,618 tons of the greenhouse gas $CO_2$ was total amount from Ansan-City in 2007. The share of energy sector greenhouse gas emissions was the highest portion of 79 % and 14 percent of transportation, 4% from the waste sector, 3 % from landuse/forest sector.

• Journal of Climate Change Research
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• v.9 no.3
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• pp.245-251
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• 2018

Creating Shared Value (CSV) is a new business paradigm in which enterprises benefit from social works. The goal of this study is to assess greenhouse gas emission reduction through CSV-related activities of Yuhan-Kimberly (YK) Company. YK Company has planted over 50 million trees between 1984 and 2016 as a part of CSV activities. Through planting of trees, annual $CO_2 $ emission reduction ranged from 196.2 thousand to $336.3\;thousand\;tCO_2-eq$ depending on forest type in 2016, representing 44 million to 84 million KRW. Those results indicate that the company can contribute to reduction of greenhouse gas emissions as well as obtain economic profits through CSV-related activities. Furthermore, this study provides motives for other companies interested in similar CSV projects.

• Resources Recycling
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• v.22 no.6
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• pp.3-11
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• 2013

This study was carried out to estimate greenhouse gas reduction potentials under treatment methods of combustible wastes excavated from closed landfill. The treatment methods of solid wastes were landfilling, incineration, and production of solid recovery fuel. The greenhouse gas reduction potentials were calculated using the default emission factor presented by IPCC G/L method of IPCC (Intergovernmental Panel on Climate Change). The composition of excavated waste represented that screened soil was the highest (65.96%), followed by vinyl/plastic (19.18%). This means its own component is similar to the other excavated waste from unsanitary landfill sites. Additionally, its bulk density was 0.74 $t/m^3$. In case of landfilling of excavated waste, greenhouse gas emission quantity was 60,542 $tCO_2$. In case of incineration of excavated waste, greenhouse gas emission quantity was 9,933 $tCO_2$. However, solid recovery fuel from excavated waste reduced 33,738 $tCO_2$ of the greenhouse gas emission quantity. Therefore, solid recovery fuel production is helpful to reduce of greenhouse gas emission.

• Journal of Climate Change Research
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• v.5 no.3
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• pp.219-230
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• 2014

In this study, greenhouse gas emission of magnesium industry was estimated and the reduction potential of the greenhouse gas emission was evaluated with reduction technologies. Default value of IPCC guideline was used to calculate the greenhouse gas emission and $SF_6$ alternatives were considered in reduction potential. Import of magnesium ingot was 22,806 ton in 2013, which will be expected to increase to 81,700 ton with 20% rate in 2020. Magnesium ingot was consumed to produce magnesium alloy in diecasting process. Recently, commercial production of crown magnesium and magensium plate began. Based on ingot consumption, $CO_2$ emission of domestic magnesium industry was estimated to 504,000 ton, which is about 0.79% of domestic industrial emissions. Reduction potential of diecasting process was estimated to 489,320 ton by changing SF6 to alternative gases such as HFC-134a, Novec-612. Emission factor of Tier 3 level should be developed to enhance the accuracy of greeenhouse gas emission of magnesium industry.

• Journal of Korea Society of Waste Management
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• v.35 no.7
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• pp.606-615
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• 2018

Over the past two decades, the options for solid waste management have been changing from land disposal to recycling, waste-to-energy, and incineration due to growing attention for resource and energy recovery. In addition, the reduction of greenhouse gas (GHG) emission has become an issue of concern in the waste sector because such gases often released into the atmosphere during the waste management processes (e.g., biodegradation in landfills and combustion by incineration) can contribute to climate change. In this study, the emission and reduction rates of GHGs by the municipal solid waste (MSW) management options in D city have been studied for the years 1996-2016. The emissions and reduction rates were calculated according to the Intergovernmental Panel on Climate Change guidelines and the EU Prognos method, respectively. A dramatic decrease in the waste landfilled was observed between 1996 and 2004, after which its amount has been relatively constant. Waste recycling and incineration have been increased over the decades, leading to a peak in the GHG emissions from landfills of approximately $63,323tCO_2\;eq/yr$ in 2005, while the lowest value of $35,962tCO_2\;eq/yr$ was observed in 2016. In 2016, the estimated emission rate of GHGs from incineration was $59,199tCO_2\;eq/yr$. The reduction rate by material recycling was the highest ($-164,487tCO_2\;eq/yr$) in 2016, followed by the rates by heat recovery with incineration ($-59,242tCO_2\;eq/yr$) and landfill gas recovery ($-23,922tCO_2\;eq/yr$). Moreover, the cumulative GHG reduction rate between 1996 and 2016 was $-3.46MtCO_2\;eq$, implying a very positive impact on future $CO_2$ reduction achieved by waste recycling as well as heat recovery of incineration and landfill gas recovery. This study clearly demonstrates that improved MSW management systems are positive for GHGs reduction and energy savings. These results could help the waste management decision-makers supporting the MSW recycling and energy recovery policies as well as the climate change mitigation efforts at local government level.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.31 no.4D
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• pp.603-611
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• 2011

After Kyoto Protocol was adopted for green gas reduction, each nations are stepping up efforts to reduce $CO_2$ of a typical green gas. Construction industry also is trying $CO_2$ reduction with the techniques of two types which are software and hardware techniques. The software technique are Passive Design considered green gas emission and the environment impact assessment by LCA. The hardware techniques are adjustment of equipment system and development of eco- friendly material. But, it is nonexistent that a study related to $CO_2$ emission considered detail process in construction industry. This study analyzed the correlation of equipment combination, $CO_2$ emission and duration by calculate $CO_2$ emission follow to equipment combination on earth-work which is the process emitted most $CO_2$ among railway bedding construction.