Reaction Characteristics of the Diesel Oxidation Catalyst of Particulate Matters from the Diffusion Flame of a Boiler Burner

김화남,최병철,김태준,임명택 한국자동차공학회 2008 International journal of automotive technology Vol.9 No.5

The objective of this experimental study is to investigate the characteristics of the size distribution and the number concentration of PM (particulate matters) emitted from the diffusion flame of a boiler burner, which has the same type of combustion as a diesel engine. This study is performed to investigate the emission characteristics of nanoparticles generated from diffusion combustion in diesel fuel, and it considered fuel factors and the reaction characteristics of the nanoparticles on the DOC (Diesel oxidation catalyst). The factors examined in this experiment included the sulfur content in the fuel, the blend of the diesel fuel containing biodiesel and bio-ethanol, and the concentration of engine oil (0.1% and 1.0%) blended with diesel fuel. The particle size distribution of the nanoparticles exhausted from the boiler burner was measured by an SMPS(scanning mobility particle sizer). The number concentration of PM that were smaller than 70 nm in diameter greatly increased in the rear of the DOC when fuel containing 250 ppm of sulfur was used. The experiment also suggested that the particle number concentration in both the front and rear of the DOC was lower when ULSD (ultra low sulfur diesel) fuel blended with biodiesel and bio-ethanol, which are oxygenated fuels, was used than when only ULSD fuel was used. The higher the content of engine oil in the fuel, the higher the particle number concentration was in the front and rear of the catalyst. When the first dilution air temperature is increased from 30℃ to 180oC, the nanoparticle number concentration dramatically dropped in the rear of the catalyst when fuel containing 250 ppm of sulfur was used, while the particle size distribution remained almost the same when the fuel with engine oil was used. The objective of this experimental study is to investigate the characteristics of the size distribution and the number concentration of PM (particulate matters) emitted from the diffusion flame of a boiler burner, which has the same type of combustion as a diesel engine. This study is performed to investigate the emission characteristics of nanoparticles generated from diffusion combustion in diesel fuel, and it considered fuel factors and the reaction characteristics of the nanoparticles on the DOC (Diesel oxidation catalyst). The factors examined in this experiment included the sulfur content in the fuel, the blend of the diesel fuel containing biodiesel and bio-ethanol, and the concentration of engine oil (0.1% and 1.0%) blended with diesel fuel. The particle size distribution of the nanoparticles exhausted from the boiler burner was measured by an SMPS(scanning mobility particle sizer). The number concentration of PM that were smaller than 70 nm in diameter greatly increased in the rear of the DOC when fuel containing 250 ppm of sulfur was used. The experiment also suggested that the particle number concentration in both the front and rear of the DOC was lower when ULSD (ultra low sulfur diesel) fuel blended with biodiesel and bio-ethanol, which are oxygenated fuels, was used than when only ULSD fuel was used. The higher the content of engine oil in the fuel, the higher the particle number concentration was in the front and rear of the catalyst. When the first dilution air temperature is increased from 30℃ to 180oC, the nanoparticle number concentration dramatically dropped in the rear of the catalyst when fuel containing 250 ppm of sulfur was used, while the particle size distribution remained almost the same when the fuel with engine oil was used.

OXIDATION CHARACTERISTICS OF PARTICULATE MATTER ON DIESEL WARM-UP CATALYTIC CONVERTER

Choi, B.C.,Yoon, Y.B.,Kang, H.Y.,Lim, M.T. The Korean Society of Automotive Engineers 2006 International journal of automotive technology Vol.7 No.5

Modern passenger cars with diesel engines are equipped with DOC(diesel oxidation catalyst) for the purpose of reducing HC and CO in the exhaust stream. Cold start exhaust emissions pose troubles here as on gasoline engine vehicles. As a result, some of the diesel passenger cars roll off todays the assembly lines with WCC(warm-up catalytic converter). Oxidation characteristics of the particulates in WCC is analyzed in this study by EEPS(engine exhaust particulate size spectrometer). The maximum number of PM is found to come out of WCC in sizes near 10nm when an HSDI diesel engine is operated under the conditions of high speed and medium to heavy load. When the temperature of the WCC exceeds $300^{\circ}C$, the number of PM smaller than 30 nm in diameter sharply increases upon passing through the WCC. Total mass of emitted PM gets reduced downstream of the WCC under low speed and light load conditions due to adsorption of PM onto the catalyst. Under conditions of high speed and medium to heavy load, the relatively large PM shrink or break into fine particles during oxidation process within the WCC, which results in more mass fraction of fine particles downstream of the WCC.

승용 디젤 엔진에서 엔진 주요 변수가 EGR cooler fouling에 미치는 영향 평가

박상준(Sangjun Park),이영복(Youngbok Lee),송순호(Soonho Song),전광민(Kwang Min Chun),민선기(Sunki Min),정도영(Doyoung Chung),정종화(Chonghwa Chung) 한국자동차공학회 2012 한국자동차공학회 부문종합 학술대회 Vol.2012 No.5

EGR technology is one of the method to achieve NOx reduction from diesel engine. Cooled EGR system has been used to meet the strict emission regulation. However, when using this system for a long period of time, a fouling phenomenon defined by deposition of PM on cooler wall. As a result, the performance of the engine and NOx reduction rate was deteriorated. In this study, the effects of various variables (coolant temperature, flow rate, BMEP) on EGR cooler fouling were evaluated using engine exhaust partial flow at steady-state. In addition, in order to evaluate the diesel oxidation catalyst effect on EGR cooler fouling, the experiment was carried out about the diesel oxidation catalyst when it was installed before the EGR cooler. The effectiveness drop of the EGR cooler became larger as the coolant temperature decreased. But flow rate did not affect the fouling phenomenon. Furthermore, the effectiveness of the EGR cooler was improved with diesel oxidation catalyst.

OXIDATION CHARACTERISTICS OF PARTICULATE MATTER ON DIESEL WARM-UP CATALYTIC CONVERTER

B. C. CHOI,Y. B. YOON,H. Y. KANG,M. T. LIM 한국자동차공학회 2006 International journal of automotive technology Vol.7 No.5

Modern passenger cars with diesel engines are equipped with DOC (diesel oxidation catalyst) for the purpose of reducing HC and CO in the exhaust stream. Cold start exhaust emissions pose troubles here as on gasoline engine vehicles. As a result, some of the diesel passenger cars roll off todays the assembly lines with WCC (warm-up catalytic converter). Oxidation characteristics of the particulates in WCC is analyzed in this study by EEPS (engine exhaust particulate size spectrometer). The maximum number of PM is found to come out of WCC in sizes near 10㎚ when an HSDI diesel engine is operated under the conditions of high speed and medium to heavy load. When the temperature of the WCC exceeds 300oC, the number of PM smaller than 30 ㎚ in diameter sharply increases upon passing through the WCC. Total mass of emitted PM gets reduced downstream of the WCC under low speed and light load conditions due to adsorption of PM onto the catalyst. Under conditions of high speed and medium to heavy load, the relatively large PM shrink or break into fine particles during oxidation process within the WCC, which results in more mass fraction of fine particles downstream of the WCC.

디젤 연료의 황농도에 따라 배출되는 입자상물질의 산화촉매에서 반응특성

김화남(Hwanam Kim),성용하(Yongha Sung),정길성(Kil Sung Jung),강한용(Hanyong Kang),최병철(Byungchul Choi),임명택(Myung Taeck Lim) 한국자동차공학회 2006 한국자동차공학회 춘 추계 학술대회 논문집 Vol.- No.-

Diesel particulate matters are one of a major harmful component of the emission under strict regulations. Diesel oxidation catalyst (DOC) is using to reduce hydrocarbon and carbon monoxide in current diesel engines. The objectives of this study are to further understand the formation characteristics of nano-particles in nuclei mode, for the purpose we examined formation of nano-particle with various sulfur concentrations in diesel fuel in both of a common-rail diesel engine and a boiler for household heating equiped with DOC. Experimental parameters adopted equivalence ratio, dilution air temperature, fuel injection pressure and engine speed. The particle size distribution and the number concentration were measured by SMPS. PM nano-particle number in boiler exhaust gas was increased by diesel fuel with 500 ppm sulfur, and when the exhaust gas temperature is more than 300℃, the particles range of 20 to 40 ㎚ increased greatly in the rear of the DOC. Number of the particle smaller than 30 ㎚ size increased as the sulfur concentration in the diesel fuel increased in the common-rail diesel engine.

Fe-doped LaCoO3 perovskite catalyst for NO oxidation in the post-treatment of marine diesel engine’s exhaust emissions

안소라,송경호,이관영,박기태,정순관,김학주 한국화학공학회 2018 Korean Journal of Chemical Engineering Vol.35 No.9

New post-treatment process for marine diesel engine exhaust emissions was proposed by combining NO oxidation and wet scrubbing technology for the simultaneous removal of SOX, NOX and PM. NO, insoluble in aqueous scrubbing absorbent, is preferentially oxidized to NO2, which then turns fully soluble in it. Fe substituted LaCo1 xFexO3 perovskite catalysts were developed for NO oxidation to NO2. The catalysts were prepared by co-precipitation method and analyzed with XRD, XRF, BET, FT-IR, NO-TPD and XPS techniques. Crystal structure change from rhombohedral to orthorhombic was observed with the increased amount of Fe substituted in the B site of the perovskite by XRD analysis. From FT-IR and NO-TPD analysis, nitrate on perovskite species was found to be the active species for NO oxidation. Quantitative analysis was performed within the prepared catalysts. Catalytic activity was measured using a packed bed reactor operated at 150-400 oC, atmospheric pressure and with gas hourly space velocity (GHSV) of 20,000 h1 using a simulated exhaust gas composed of NO 400 ppm, O2 10% balanced with N2. Formation of Fe4+ cation enhanced the redox property as well as the mobility of the lattice oxygen present in the perovskite catalysts, confirmed by XPS analysis. Reaction mechanism of NO oxidation on Fe substituted LaCo1xFexO3 was discussed based on Mars-van Krevelen mechanism.

ULSD 使用에 따른 機關性能과 排氣가스 및 DOC에 미치는 影響에 關한 實驗的 硏究

한영출,박귀열,박봉규 국민대학교 생산기술연구소 2002 공학기술논문집 Vol.25 No.-

Automobile industries have been developed rapidly mainly as a key manufacturing industry. On the other hands, atmosphere pollution is getting worse noticeably than in any other times. In the diesel emission, PM(Particulate Matter) and NOx(Nitrogen Oxidation) have been exhausted with a great amount and the regulation is getting stringent. In order to develop a low emission engine, it is necessary to research on better quality of fuel. Sulfur contained in fuel is transformed to sulfur compound by DOC(Diesel Oxidation Catalyst) and then it causes to increase of sulfate-laden PM on the surface of catalyst. Recently diesel automobile industries are focused on the development of reduction techniques on PM by modifying combustion of sulfur in fuel. In this research, ULSD(Ultra Low Sulfur Diesel) is used as a fuel and some experimental results are investigated. ULSD can reduce not only PM but also gas materials because cetane value, flash point, distillation 90%, pour point and viscosity are improved in the process of desulfurization. However, excessively reduced sulfur may cause to decrease lubricity of fuel and engine performance in fuel injection system. Therefore, it requires only modest adjusted amount of sulfur can improve engine performance and DOC, as well as decrease of emission.

메탈 DOC+cDPE의 강제재생 온도에 따른 열화 특성

고상철(SangChul Ko),오광철(KwangChul Oh),정재우(Jae-Woo Chung),김덕진(DeokJin Kim),염경민(Kyoungmin Yeom),서충길(Choong-Kil Seo) 한국자동차공학회 2013 한국자동차공학회 학술대회 및 전시회 Vol.2013 No.11

Diesel vehicles are considered as one of major sources of PM, recently In-use diesel vehicle and retrofit. One of the problems of the exhaust gas temperature some diesel vehicle and retrofit is too low to apply passive regeneration DPF systems. In this study it was carried out conversion efficiency test for fresh and aged catalyst on metal DOC with cDPF. Also it was evaluated the characteristics of CO, THC conversion according to aging conditions.

메탈 DOC의 수열 열화에 따른 특성

고상철(SangChul Ko),오광철(KwangChul Oh),서충길(Choong-Kil Seo),정재우(Jae-Woo Chung),김덕진(DeokJin Kim),이춘범(ChunBum Lee) 한국자동차공학회 2012 한국자동차공학회 학술대회 및 전시회 Vol.2012 No.11

Recently, reduction of CO and THC, as well as the DOC will be used for the regeneration of the DPF. DOC deactivated by repetitive regeneration and the deactivation progresses, depending on the conversion decrease of CO, THC and NO. The metal DOC In this study used washcoat on a metal mesh plate is raised. Deactivated rapidly up to 10 hours of hydrothermal deterioration after 25, 45 hours in the deactivation rate was reduced. Results of the TEM analysis, Pt particle size increased according to the increase of the temperature and time of hydrothermal aging, this reason is due to sintering, migration and agglomeration of Pt particles.

예혼합 압축 착화 엔진용 저온 산화촉매의 성능 평가

정길성(Kil Sung Jung),김화남(Hwanam Kim),성용하(Yongha Sung),최병철(Byungchul Choi),임명택(Myung Taeck Lim) 한국자동차공학회 2006 한국자동차공학회 춘 추계 학술대회 논문집 Vol.- No.-

HCCI engines exhaust gas that contains THC and CO at a level comparable to the gasoline engines. Development of exhaust treatment devices like DOC's with high conversion efficiency especially at low temperature is therefore very important for commercialization of HCCI engines. Experimental DOC's are designed and fabricated in this study using 600 cpsi monolith, coated with either a L type or H type wash coat. Different amount of platinum is impregnated on the washcoat layers before canning and performance tests. Experimental results show that DOC's with low-temperature type wash coat have higher HC conversion efficiency at low exhaust gas temperature in comparison with those of high-temperature type wash co at and heavier Pt loading. DOC's with heavier Pt loading show higher HC conversion efficiency at exhaust temperature over 300℃. CO conversion is above 90 % on all types of DOCs as long as the exhaust temperature stays over 200 ℃.