• Proceedings of the Korea Air Pollution Research Association Conference
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• 1999.10a
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• pp.451-452
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• 1999

석탄이나 석유와 같은 화석연료의 연소 시 대기 중에 발생되는 황산화물의 배출저감 방법으로서 사용연료의 황 함유량을 감소시키는 연소 전 처리방법과 연소과정 중 제거방법, 연소 후 제거하는 방법으로 구분할 수 있다. 본 논문에서는 전기 생산능력 40만 kW 급 중유화력 발전소의 연료 연소 후 배기가스 중 황 성분을 제거하는 방법으로 석회석 슬러리와 배기가스를 효과적으로 접촉시켜 SOx 와 먼지 등의 환경오염물질을 제거하고 부산물로 재활용 가능한 고순도의 석고를 생산하게 되는 JBR (Jet Bubbling Reactor) 형식의 습식 석회석-석고법 배연탈황 시스템을 소개하고자 한다.(중략)

• Transactions of the Korean Society of Automotive Engineers
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• v.10 no.2
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• pp.80-86
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• 2002

A fuel injection system has an important role in the performance and emission gas in a diesel engine. In this paper, an experimental study has been performed to verify the effect of the performance and the emission gas with the factors such as diameters of an injection nozzle hole, diameters of an injection pipe, and injection timing in the fuel injection system. We have obtained the results that the fuel consumption ratio is reduced and NOx concentration is increased as the smaller diameter of injection nozz1e hole, the smaller diameter of injection pipe, and more advanced injection timing. They show that optimizing the factors of fuel injection system is significant to enhance the performance of the engine system and consumption ratio of fuel, smoke, and NOx.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.9
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• pp.196-205
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• 2016

The exhaust gas discharged by cars not only threatens the health of the human body, but also contributes to global warming, due to the resulting increase in the concentrations of ozone, fine dust and carbon dioxide. Therefore, the government has steadily implemented careful inspection systems for exhaust emissions, in order to efficiently regulate the exhaust gas of cars. Studies on reducing the exhaust emissions of automobiles have been conducted in various fields, including ones designed to reduce the generation of HC, NOx, and $CO_2$ in the exhaust emission of vehicles. However, there have been insufficient studies on the reduction of the exhaust emission for old diesel vehicles. To develop careful inspection systems for the exhaust emissions of old diesel vehicles, studies on the reduction of the exhaust emissions and improvement of power are necessary by cleaning the carbon sediment in both the intake manifold and injector. Therefore, in this study, we analyzed and compared the amounts of gas emitted when simultaneously cleaning or not cleaning the intake manifold and injector of diesel automobiles with mileages over 80,000 km and operating periods over 5 years. The experimental results showed that in the case where the intake manifold and injector were simultaneously cleaned, there was a decline of 75.2% in the gas emission compared to the cases where only the manifold or injector is cleaned. Also, it was found that simultaneously cleansing the intake manifold and injector enabled the exhaust standard to be satisfied for less than 30% within 8.5 sec.

• Transactions of the Korean Society of Automotive Engineers
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• v.22 no.7
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• pp.8-15
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• 2014

In order to satisfy stringent future emission regulation in diesel engines, systematic approaches to mitigate the harmful exhaust emissions were developed, such as engine hardware, fuel injection equipment, engine control, and after-treatment system. In this study, to improve the nano-particle and NOx emissions from a state-of-the-arts diesel engine, effect of various EGR and fuel injection pressure with combustion analysis were evaluated. Size-resolved nano-particle and NOx emissions showed trade-off characteristics with various EGR rate and increment of fuel injection pressure.

• Journal of the Korean Society of Marine Environment & Safety
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• v.29 no.5
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• pp.497-504
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• 2023

In this study, Selective catalytic reduction (SCR) + Diesel particulate filter (DPF) system was installed on a ship with a low-speed engine to conduct the on-board test. The target ship (2,881 gross tons, rated power 1,470 kW@240 rpm ×1) is a general cargo ship sailing in the coastal area. Drawing development, approvals and temporary survey of the ship were performed for the installation of the after-treatment system. For performance evaluation, the gaseous emission analyzer was used according to the NOx technical code and ISO-8178 method of measurement. The particulate matter analyzer used a smoke meter to measure black carbon, as discussed by the International Maritime Organization (IMO). Tests were conducted using MGO (0.043%) and LSFO (0.42%) fuels according to the sulfur content. The test conditions were selected by considering the engine rpm (130, 160 and 180). Gaseous emission and particulate matter (smoke) were measured according to the test conditions to confirm the reduction efficiency of the after treatment system. The results of NOx emission and particulate matter (smoke) revealed that reduction efficiency was more than 90%. The exhaust pressure met the allowable back pressure (less than 50 mbar). This study confirms the importance of the on-board test and the potential of SCR + DPF systems as a response technology for reducing nitrogen oxides and particulate matter.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2015.10a
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• pp.1065-1066
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• 2015

자동차의 수요가 폭발적으로 늘어났으며, 늘어난 자동차 대수를 고려하여 자동차 검사소 또한 많이 늘어났다. 그러나 최근에는 낮은 유지비용과 이동의 편의성으로 인하여 이륜자동차의 수요가 지속적으로 증가하고 있다. 이륜자동차의 경우 검사제도의 미비로 인하여 대기환경오염 및 불법개조로 인한 여러 가지 사회적 문제가 발생하고 있다. 이러한 이유로 최근에는 이륜자동차의 체계적 관리를 통하여 불법개조를 단속하고, 배기가스 오염물질에 의한 대기오염 및 이륜자동차 소음관리를 위하여 이륜자동차에 대한 검사 제도가 더욱 강화되고 있다. 본 논문에서는 중고차 성능점검 시스템 및 기능종합진단 시스템의 아키텍처를 통하여 이륜자동차에 적용되는 종합관리시스템 적용될 수 있는 통신 프로토콜을 분석하고 개발에 필요한 중요한 설계요소를 제시하고자 한다.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.4
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• pp.641-647
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• 2017

In order to meet the stricter emission regulations, the proportion of after-treatments for vehicles and vessels has been increasing gradually. The objective of this study is to investigate the physicochemical properties according to ash cleaning agents of CDPF for Diesel Engines. Penetrating agents with strong penetration into ash and a surfactant component to mix water and oil were prepared properly. The cleaning characteristics of S1 sample were good. Washcoat loss rate of S1 sample was lower by about 2.2% because of less KOH component and lower Na2SiO3 content. Washcoat loss rate of S4 sample with an added KOH and Na2SiO3 components by penetration agents was increased by about 13%. In terms of less than about 13% of CDPF's washcoat loss rate, it was able to reduce the harmful gas components.

• Journal of the Korean Applied Science and Technology
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• v.35 no.4
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• pp.1108-1119
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• 2018

As the interest on the air pollution is gradually rising at home and abroad, automotive and fuel researchers have been studied on the exhaust and greenhouse gas emission reduction from vehicles through a lot of approaches, which consist of new engine design, innovative after-treatment systems, using clean (eco-friendly alternative) fuels and fuel quality improvement. This research has brought forward two main issues : exhaust emissions (regulated and non-regulated emissions, PM particle matter) and greenhouse gases of vehicle. Exhaust emissions and greenhouse gases of automotive had many problem such as the cause of ambient pollution, health effects. In order to reduce these emissions, many countries are regulating new exhaust gas test modes. Worldwide harmonized light-duty vehicle test procedure (WLTP) for emission certification has been developed in WP.29 forum in UNECE since 2007. This test procedure was applied to domestic light duty diesel vehicles at the same time as Europe. The air pollutant emissions from light-duty vehicles are regulated by the weight per distance, which the driving cycles can affect the results. Exhaust emissions of vehicle varies substantially based on climate conditions, and driving habits. Extreme outside temperatures tend to increasing the emissions, because more fuel must be used to heat or cool the cabin. Also, high driving speeds increases the emissions because of the energy required to overcome increased drag. Compared with gradual vehicle acceleration, rapid vehicle acceleration increases the emissions. Additional devices (air-conditioner and heater) and road inclines also increases the emissions. In this study, three light-duty vehicles were tested with WLTP, NEDC, and FTP-75, which are used to regulate the emissions of light-duty vehicles, and how much emissions can be affected by different driving cycles. The emissions gas have not shown statistically meaningful difference. The maximum emission gas have been found in low speed phase of WLTP which is mainly caused by cooled engine conditions. The amount of emission gas in cooled engine condition is much different as test vehicles. It means different technical solution requires in this aspect to cope with WLTP driving cycle.

• Korean Chemical Engineering Research
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• v.59 no.1
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• pp.60-67
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• 2021

This study presented techno-economic analysis of a 500 MWe oxy-coal power plant with CO2 capture. The power plant included a circulating fluidized-bed (CFB), ultra-supercritical steam turbine, flue gas conditioning (FGC), air separation unit (ASU), and CO2 processing unit (CPU). The dry flue gas recirculation (FGR) was used to control the combustion temperature of CFB. One FGR heat exchanger, one heat exchanger for N2 stream exiting ASU, and a heat recovery from CPU compressor were considered to enhance heat efficiency. The decrease in the temperature difference (ΔT) of the FGR heat exchanger that means the increase in heat recovery from flue gas enhanced the electricity and exergy efficiencies. The annual cost including the FGR heat exchanger and FGC cooling water was minimized at ΔT = 10 ℃, where the electricity efficiency, total capital cost, total production cost, and return on investment were 39%, 1371 M$, 90 M$, and 7%/y, respectively.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.08a
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• pp.82.1-82.1
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• 2013

SPOES(Self Plasma Optical Emission Spectroscopy)는 반도체 및 LCD 제조 장비의 Foreline에 장착되는 센서로써, Foreline에 흐르는 Gas를 이온화시켜 이때 발생되는 빛을 분광시켜 공정의 상태 및 장비의 상태등을 종합적으로 점검할 수 있는 센서입니다. SPOES의 최대 장점은 공정 장비에 영향을 주기 않으면서 공정을 진단할 수 있고, 장비의 메인챔버에서 플라즈마 방전이 발생하지 않는 RPS (Remote Plasma System)등에 적용이 가능하며, 설치 및 분해이동과 운용이 용이한 장점이 있습니다. 하지만, SPOES는 오염성 가스 및 물질에 의한 오염에 취약한 단점이 있습니다. 예컨대, 플라즈마 방전에 의한 부산물들이 SPOES의 내부에 있는 윈도우의 렌즈에 부착되어 감도를 저하시켜, SEOES의 수명을 단축시킵니다. 또한 오염 물질이 SPOES 내부의 방전 CHAMBER에 증착되어 플라즈마 방전 효울을 저하시켜 센서의 효율을 저하시킵니다. 예를들면, 장비의 공정 챔버에서 배출되는 탄소와 같은 비금속성 오염물질과 텅스텐과 같은 금속성 오염물질이 SPOES의 방전 CHAMBER 내벽과 윈도우에 증착되어 오염을 유발합니다. 오염이 진행된 SPOES는 방전 CHAMBER의 오염으로 CHAMBER의 유전율을 변화시켜, 플라즈마 방전 효율의 저하를 가져오고, 윈도우의 오염은 빛의 투과율을 저하시켜, OES 신호의 감도를 저하시켜, SPOES 감도를 저하시키는 요인으로 작용합니다. 이러한 문제를 해결하기위한 방법으로 능동형 오염 방지 기술을 채용 하였습니다. 능동형 오염 방지 기법은 SPEOS의 방전 챔버에서 플라즈마 방전시 발생하는 진공의 밀도차를 이용하는 기술과 방전 챔버와 연결된 BYPASS LINE에 의해 발생되는 오염물질 자체 배기 시스템, 그리고 고밀도 플라즈마 방전을 일으키는 멀티 RF 기술 및 고밀도 방전을 일으키는 챔버 구조로 구성 되어 있습니다. 능동형 오염 방지 기법으로 반도체 공정에서 6개월 이상의 LIFETIME을 확보 할 수 있고, 고밀도 플라즈마로 인한 UV~NIR 영역의 감도 향상등을 확보 할 수 있습니다.