대형 2행정 디젤엔진의 SCR 및 EGR 시스템에 의한 NOx 배출물 저감 특성에 관한 연구

배명환(Myung-whan Bae),류지호(JiHo Ryu),김성완(SeongWan Kim),박희성(Hui-seong Park) 대한기계학회 2020 大韓機械學會論文集B Vol.44 No.7

본 연구의 목적은 선박용 대형 2행정 디젤엔진에 있어서 NOX 배출물에 대한 Tier III 규제값에 따르는 EGR 시스템의 적용 가능성을 확인하는 것이다. 디젤엔진에 Miller 사이클, SCR 및 EGR 시스템을 적용하여 엔진부하에 따른 최대 연소압력, 최대 압축압력, 배기온도, 연료소비율, O₂ 및 NOX 배출물을 실험에 의해 측정하여 비교하였다. 실험 결과는 Miller 사이클을 적용한 경우, 연비는 SCR 및 EGR 시스템보다 높았고, ISO 수정식에 의한 NOX 배출물의 최종 산정값은 Tier II 규제값을 만족하였다. 또한, SCR 및 EGR 시스템을 적용하여 측정한 NOX 배출물의 ISO 수정식에 따른 산정값은 Tier III 규제값을 만족하였고, EGR 시스템에 있어서 NOX 배출물의 산정값은 SCR 시스템보다 0.4 g/kWh 더 많았지만, EGR 시스템 적용에 의해 규제값을 만족시킬 수 있음을 알았다. The purpose of this study is to identify the applicability of EGR system complying with the Tier III regulation values for NOx emissions in a marine large two-stroke diesel engine. The Miller cycle, SCR and EGR systems were applied to the diesel engine, and the maximum combustion pressure, maximum compression pressure, exhaust temperature, fuel consumption rate, and the O₂ and NOx emissions as a function of engine load in each case were experimentally measured and subsequently compared. It was concluded that the fuel economy was higher than those of SCR and EGR systems, and the final estimated NOx emissions bases on the modified ISO formula satisfied the Tier II regulation values when the Miller cycle was applied. In addition, it was found that the estimated values of NOx emissions measured by applying the SCR and EGR systems corresponding to the modified ISO formula met in the Tier III regulation values, and this value of NOx emissions by EGR system was 0.4 g/kWh more than that of SCR system, but the regulation value could be met by the application of EGR system.

모형 가스터빈 연소기에서 촉매에 의한 유해 배출물 저감 특성

임경달(Kyung-Dal Lim) 산업기술교육훈련학회 2011 산업기술연구논문지 (JITR) Vol.16 No.2

The interests on the environmental problem associated with energy are growing fast in recent years. Many countries enforce the trade restriction such as Green Round in order to preserve their environment. In order to solve these problems, we should develop the new combustion technique and flame diagnosis method in the combustion field. And, it is necessary to find basic information used for improvement of efficiency and reduction to combustion emission. In order to this purpose, this paper is to investigate the combustion emission characteristics changing excess air ratio(a), catalytic materials(Pt, Pd, Pt/Rh) and volume(0.237m3, 0.34m3) in emission after treatment system of model gas turbine combustor. For this purpose, mean temperature, CO, CO2, O2 HC and NOx concentration were measured by changing excess air ratio, catalytic materials and volume at inlet and outlet of catalyst. Each subject is summarized as following. The reduction effects of Pt catalyst-loaded for HC, CO is more notable in the same volume. It was found that volume change of Pt/Rh catalyst-loaded have not an influence on the reduction effects of HC, CO. The reduction effects of Pt/Rh catalyst-loaded for NOx is more notable without regard to the excess air ratio. In case of Pt, Pd catalyst-loaded, excess air ratio have an influence on the reduction effects of NOx and was more notable a=1.26.

가솔린엔진 운행자동차 배기 배출물에 미치는 튜닝 흡기 및 배기 시스템의 효과에 관한 연구

배명환,구영진,박희성 대한기계학회 2019 大韓機械學會論文集B Vol.43 No.5

The purpose of this study is to obtain the basic data of engine tuning inspection by confirming the working possibility of effective engine tuning and identifying the characteristics of tuned engine that are no safety and environmental problems in a driving car of gasoline engine. The actual driving car with a four-cycle, four-cylinder DOHC, turbo-intercooler, water-cooled gasoline engine operating under four types of non-tuning, and tuning 2-1, 2-2 and 2-3 was applied to investigate the effects of tuned engine on the characteristics of excess air ratio and exhaust emissions by the low speed idle and acceleration simulation mode inspections. The tuned parts of gasoline engine in a driving car include the intake manifold, intake pipe, air filter, exhaust manifold, exhaust pipe and silencer. It was found that the measured values of CO emission, THC emissions and excess air ratio by the low speed idle inspection method, and NOX, CO and THC emissions by the acceleration simulation mode inspection method for the gasoline non-tuned and tuned engines of driving car were all satisfied with the inspection standard without any environmental problems. However, the measured values of tuned engine were greater than those of non-tuned engine. 본 연구의 목적은 가솔린엔진 운행자동차에 있어서 안전과 환경에 문제가 없는 효과적인 엔진튜닝의 작업가능성을 확인하고, 튜닝엔진의 특징을 파악하여 엔진튜닝 검사의 기초자료를 확보하는 것이다. 저속 공회전 및 정속 모드 검사에 의해 공기과잉률 및 배기 배출물을 측정해 튜닝엔진의 효과를 조사하기 위하여 4행정, 4기통 DOHC, 터보 인터쿨러, 수냉 가솔린엔진에 대한 비튜닝 및 튜닝 2-1, 2-2, 2-3의 4종류를 실제 운행자동차에 적용하였다. 운행자동차에 대한 가솔린엔진의 튜닝부분은 흡기 다기관, 흡기 파이프, 공기필터, 배기 다기관, 배기 파이프 및 소음기이다. 운행자동차 가솔린 비튜닝 및 튜닝 엔진에 대해 저속 공회전 검사방법에 의한 CO 배출물, THC 배출물 및 공기과잉률과 정속모드 검사방법에 의한 NOX, CO 및 THC 배출물 측정값은 모두 환경에 대한 문제가 없이 검사기준에 만족하였지만, 이 측정값들은 튜닝엔진의 경우가 비튜닝엔진보다 더 증가되었음을 알았다.

소형 선박용 디젤엔진에서 엔진초기화 세팅을 통한 연소성능 및 배기배출물 개선에 관한 연구

류영현,정균식,남정길 한국마린엔지니어링학회 2019 한국마린엔지니어링학회지 Vol.43 No.7

Tugboats that sail along a coast may experience poor engine combustion performance due to frequent entry and departure and frequent change of the ship’s speed. Decrease in combustion performance may cause an increase in specific fuel consumption and an increase in harmful exhaust emissions. Consequently, the engine maintenance cycle may be shortened, and its maintenance cost may increase. An initialization method that returns a small marine diesel engine to the state of a new engine needs to be employed to improve the combustion performance and reduce exhaust emissions. This method involves adjusting the matching of the exhaust turbocharger initialization, fuel injection timing, and fuel injection amount. By using this method, it is possible to optimize the engine by considering its future load range. This study measured and diagnosed the combustion condition of a small ship (tugboat) equipped with a 4-stroke diesel engine, which is currently operated. The methods to improve combustion performance and reduce exhaust emissions were then suggested. When the engine performance was improved through engine initialization, the maximum compression pressure increased by 34.9%, maximum explosion pressure by 24.7%, indicated mean effective pressure by 10.9%, engine output by 20.0%, and specific fuel consumption by 4.2%. Additionally, the exhaust gas temperature decreased by an average of 39.2 °C. The result of exhaust emission measurement revealed that particulate matter decreased by 55.8%, carbon dioxide known as greenhouse gas by 12.5%, carbon monoxide by 74.4%, and nitrogen oxide by 4.4%. 연안을 항해하는 소형선박(Tug boat)은 잦은 입·출항과 잦은 선속 변경으로 엔진의 연소성능이 저하될 수 있다. 연소성능의 저하는 연료 소비율 증가 및 유해 배기배출물 증가의 원인이 될 수 있다. 또한 그러한 이유로 엔진정비 주기가 짧아질 수 있어 엔진정비 비용이 증가될 수 있다. 소형 선박용 디젤엔진의 연소성능 및 배기배출물을 개선하기 위하여 제시된 방안으로 엔진을 신조시의 상태로 돌려보내는 초기화 방법으로 배기 과급기 초기화 매칭, 연료분사시기 및연료분사량을 조정하는 것이며, 이 방법을 이용하여 향후 엔진의 사용부하영역을 고려한 최적화도 가능하다. 본 연구에서는 현재 운항되고 있는 4행정 디젤엔진이 탑재된 소형선박(Tug boat)의 연소상태를 계측하여 진단하였으며, 연소성능개선 및 배기배출물 저감 방안을 제시하였다. 엔진초기화를 통해 엔진성능이 개선된 후에 최고압축압력은 34.9%, 최고폭발압력은 24.7%, 도시평균유효압력은 10.9%, 엔진 출력은 20.0% 증가하였으며, 연료소비율도 4.2% 향상되었다. 또한, 배기가스 온도는 평균 39.2 ℃ 감소하는 결과를 얻을 수 있었다. 배기배출물의 계측결과, Dust(PM)는 엔진성능 개선 후에55.8% 감소하였으며 GHG(Green House Gas)로 알려진 이산화탄소는 12.5%, 일산화탄소는 74.4% 감소하였고 질소산화물도 4.4% 감소되는 결과를 얻었다.

FGR 시스템 동력 플랜트 보일러의 성능 및 배기 배출물에 미치는 재순환 배기의 영향에 관한 연구

배명환(Myung-whan Bae),정광호(Kwong-ho Jung),박성범(Sung-bum Park) 대한기계학회 2016 大韓機械學會論文集B Vol.40 No.4

자연순환식 압입 송풍식 수관보일러에 FGR시스템을 설치하여 보일러 부하 및 공기량 댐퍼개도를 파라미터로 해서 FGR률에 따른 성능 및 배기 배출물에 미치는 재순환 배기의 영향을 조사하였다. 본 연구의 목적은 NOx 배출물을 저감시키기 위하여 동력플랜트 보일러에 FGR시스템을 적용하는 것이다. 연소를 활성화시키기 위해 0 ∼ 20%의 연소용 공기를 화염 내에 공급한다. 공기상자 상부에 설치된 2단 연소시스템의 흡입댐퍼를 0° ∼ 90° 사이에서 레버를 조작하여 열면, 버너로 공급되는 연소용 공기가 변화된다. 증발률당의 연료소비율은 FGR률의 증가에 따라 증가 혹은 감소의 명확한 경향을 나타내지 않았고, 동일 공기량 댐퍼개도에서는 FGR률이 증가할수록, 또한, 보일러 부하가 감소할수록 NOx 배출물이 감소되었다. 매연 배출물은 전기 집진기에서 86.7%의 포집효율로 매연이 제거되었기 때문에, 보일러 부하, 공기량 댐퍼 개도 및 FGR률의 운전조건에 관계없이 극소량의 매연이 배출되었다. The effect of recirculated exhaust gas on performance and exhaust emissions with FGR rate are investigated by using a natural circulation, pressurized draft and water tube boiler with FGR system operating at several boiler loads and over fire air damper openings. The purpose of this study is to apply the FGR system to a power plant boiler for reducing NOx emissions. To activate the combustion, the OFA with 0 to 20% is supplied into the flame. When the suction damper of two stage combustion system installed in the upper side of wind box is opened by handling the lever between 0° and 90°, also, the combustion air supplied to burner is changed. It is found that the fuel consumption rate per evaporation rate did not show an obvious tendency to increase or decrease with rising the FGR rate, and NOx emissions at the same OFA damper opening are decreased, as FGR rates are elevated and boiler loads are dropped. While a trace amount of soot is emitted without regard to the operation conditions of boiler load, OFA damper opening and FGR rate, because soot emissions are eliminated by the electrostatic precipitator with a collecting efficiency of 86.7%.

디젤-에탄올 혼합연료의 에탄올 함량이 미세 그을음(Soot) 입자 배출특성에 미치는 영향

박수한(Su Han Park),차준표(Junepyo Cha),권석주(Seokju Kwon),박성욱(Sungwook Park),이창식(Chang Sik Lee) 대한기계학회 2011 大韓機械學會論文集B Vol.35 No.12

본 연구의 목적은 디젤-에탄올 혼합연료로 운전되는 디젤엔진에서 에탄올 혼합비율이 나노 크기 입자 배출 특성에 미치는 영향을 분석하는 것이다. 엔진의 연소 및 배기 배출물 특성은 배기량 373cc 의 단기통 디젤엔진과 배기 배출물 측정 장치, SMPS 를 이용하여 실험하였다. 그을음(soot) 배출은 착화지연기간이 길어짐에 따라 증가하였다. 에탄올 혼합비율이 증가함에 따라 나노 입자의 총 개수 및 질량은 대체로 감소하는 경향을 나타냈다. 그러나 에탄올이 30% 혼합되었을 때 그을음(soot) 입자의 응결로 인해 큰 입자의 수 분포가 증가하였으며, 질량 또한 크게 증가하였다. The purpose of this study is to investigate the effect of ethanol content on the emission of nanosized particles from a diesel-ethanol blended fuel engine. The engine combustion and exhaust emission characteristics of a singlecylinder diesel engine were analyzed using an emission analyzer and an SMPS(scanning mobility particle sizer). The analysis revealed that soot emission increased with the ignition delay. When the ignition delay was fixed, an increase in the ethanol content caused a decrease in the soot emission. With an increase in the ethanol blending ratio, the number concentration and mass distribution of nanosized particles generally decreased. However, for 30% ethanol blending, large particles were observed because of the agglomeration of soot particles, and consequently, the particle mass increased.

가솔린 기관의 냉간시동 조건에서 합성가스 배기분사 기술에 의한 촉매의 활성화 온도 도달시간 단축 및 유해배출물 저감에 관한 연구

조용석(Yong-Seok Cho),이성욱(Seang-Wock Lee),원상연(Sang-Yeon Won),송춘섭(Chun-Sub Song),박영준(Young-Joon Park) 한국자동차공학회 2008 한국 자동차공학회논문집 Vol.16 No.3

Since regulations of exhaust emissions are continuously reinforced, studies to reduce harmful emissions during the cold start period of SI engines have been carried out very extensively worldwide. During the cold start period, raising the temperature of cold exhaust gas is a key strategy to minimize the light-off time of three way catalysts. In this study, a synthetic gas containing a large amount of hydrogen was injected into the exhaust manifold to raise the exhaust gas temperature and to reduce harmful emissions. The authors tried to evaluate changes in exhaust gas temperature and harmful emissions through controlling the engine operating parameters such as ignition timings and lambda values. Also the authors investigated both combustion stability and reduction of harmful emissions. Experimental results showed that combustion of the synthetic gas in the exhaust manifold is a very effective way for solving the problems of harmful emissions and light-off time. The results also showed that the strategy of retarded ignition timings and increased air/fuel ratios with ESGI is effective in raising exhaust gas temperature and reducing harmful emissions. Futhermore, the results showed that engine operating parameters ought to be controlled to lambda = 1.2 and ignition timing = 0 ~ 3° conditions to reduce harmful emissions effectively under stable combustion conditions.

커먼레일 방식 디젤기관에서 바이오디젤 적용 연구

최승훈,김홍석 한국기계기술학회 2021 한국기계기술학회지 Vol.23 No.2

In recent years, our reality is facing a serious risk of air pollution from transport vehicles. In particular, various exhaust emissions from diesel engines are pointed out as a serious cause of environmental pollution. This study attempted to study the potential of biodiesel as an alternative energy for CRDI diesel engines. When biodiesel 30% was applied, the smoke emission was reduced by 40% at 4000rpm compared to diesel. On the other hand, there was no significant difference in output, torque, and energy consumption. However, NOx emissions tended to increase compared to diesel. The applicability of biodiesel to CRDI diesel engines has been demonstrated for the characteristics of output and smoke emissions.

합성가스 배기분사 기술의 개발

양승일(Seung-Il Yang),원상연(Sang-Yeon Won),송춘섭(Chun-Sub Song),박영준(Young-Joon Park),조용석(Yong-Seok Cho) 한국자동차공학회 2007 한국자동차공학회 춘 추계 학술대회 논문집 Vol.- No.-

During a cold start period of SI engines, increasing temperature of exhaust gas is a key strategy to reduce a light-off time of a three way catalyst. This study performed injection of synthetic gas in exhaust manifold to increase exhaust gas temperature and reduce harmful emissions. Also, this study tried to evaluate changes of exhaust gas temperature and harmful emission through controls of engine operating conditions such as ignition timing and lambda control. Experimental results showed that combustion of synthetic gas in the exhaust manifold is effective in reduction of harmful emissions and decrease of the light-off time. This study also found that retarded ignition timing and increased air/fuel ratio with ESGI is effective in increasing exhaust gas temperature and reducing harmful emissions. Changing engine control variables under stable combustion condition of the engine can increase greatly effect of combustion of synthetic gas.

인터페이스 회로를 적용한 디젤기관의 배출가스특성에 관한 실험적 연구

한영출,김대열,백두성 한국공작기계학회 2003 한국생산제조학회지 Vol.12 No.6

In order to collect the engine performance data and determine optimum engine conditions, engine performance test based on interface unit were tested. This paper was carried out that engine' performance was developed using interface unit between personal computer and diesel engine. The results of the study are summarized as follows: Interface unit was developed. By using PAL, Simulation was carried in order to logic's inspection. From this test, NOx were decreased, otherwise PM were increased. By using EGR system, PM were increased by twice in the high load ranges, it was not seen to come into effect in the low load ranges. This system was tested D13 mode, the results were decreased more than 50% in the NOx emission.