• Journal of Mechanical Science and Technology
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• v.18 no.7
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• pp.1169-1176
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• 2004

Soot has a great effect on the formation of PM (Particulate Matter) in D.I. (Direct Injection) Diesel engines. Soot in diesel flame is formed by incomplete combustion when the fuel atomization and mixture formation were poor. Therefore, the understanding of soot formation in a D.I. diesel engine is mandatory to reduce PM in exhaust gas. To investigate soot formation in diesel combustion, various measurements have been performed with laser diagnostics. In this study, the relative soot diameter and the relative number density in a DJ. engine was measured by using LIS (Laser Induced Scattering) and LII (Laser Induced Incandescence) methods simultaneously which are planar imaging techniques. And a visualization D.I. diesel engine was used to introduce a laser beam into the combustion chamber and investigate the diffusion flame characteristics. To find the optimal condition that reduces soot formation in diesel combustion, various injection timing and the swirl flow in the cylinder using the SCV (Swirl Control Valve) were applied. From this experiment, the effects of injection timing and swirl on soot formation were established. Effective reduction of soot formation is possible through the control of these two factors.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.7 no.3
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• pp.278-284
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• 2006

The popularity of the diesel engine revolves around its fuel efficiency, reliability, and durability compared to the gasoline engine. However, the main disadvantage of diesel engine is the emission of particulate matter (PM) which is known as carcinogenic substance. Therefore recent progress in engine management and after-treatment systems has led to great improvement to satisfy strict emission regulations. To comply with powerful environment regulations, this study is focused on the decrease of PM(soot) as to increase significantly exhaust temperature. Therefore, HC injection is used as the method to go to the PM regeneration temperature in front of filters composed of diesel oxidation catalyst(DOC) and diesel particulate filter(DPF). And especially, LPG is used because it has good chemical reactions with exhaust. In this study, we could manufacture the test bench thought LPG injection - with which soot can be decreased-, construct 3 kinds of database(DB) according to quantity of temperature to decide the LPG injection quantity and develop DPF ECU algorithm.

• Korean Chemical Engineering Research
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• v.56 no.5
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• pp.752-760
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• 2018

The lowering of temperature for combustion of diesel particulate matters (or diesel soot) is one of the important tasks in automotive industry that is searching for a way to meet up "high-fuel efficiency, low-emission" standard. In this study, it was discussed how the use of ozone over platinum-based catalyst promotes a low-temperature soot oxidation occurred at $150^{\circ}C$. The use of platinum catalyst did not increase oxidation rate largely but was very effective in improving the selectivity of carbon dioxide. The pre-oxidation of NO into $NO_2$ using ozone was rather crucial in improving the oxidation rate of soot at $150^{\circ}C$.

• International Journal of Automotive Technology
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• v.3 no.1
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• pp.1-8
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• 2002

There is Increasing world-wide interest in diesel particulate filters (DPF) because of their proven effectiveness in reducing exhaust smoke and particulate emissions. Fine particulates have been linked to human health . DPF use requires a means to secure the bum-out of the accumulated soot, a process called regeneration. If this is not achieved, the engine cannot continue to operate. A number of techniques are available, but most are complex, expensive or have a high electrical demand. The use of fuel additives to catalyse soot bum-out potentially solves the problem of securing regeneration reliably and at low cost. Work on organo-metallic fuel additives has shown that certain metals combine to glove exceptional regeneration performance. Best performance was achieved with a combination of iron and strontium based compounds. Tests were carried out un a bed engine and on road vehicles, which demonstrated effective and reliable regeneration from a tow dose fuel additive, using a single passive DPF. No control valves, flow diverters. heaters or other devices were employed to assist regeneration. Independent particle size measurements showed that there were no harmful side effects from the use of the iron-strontium fuel additive.

• Journal of Environmental Health Sciences
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• v.33 no.1 s.94
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• pp.36-42
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• 2007

Diesel PM can be controlled using Diesel Particulate Filter, which can effectively reduce the level of soot emissions to ambient background levels. In the Heavy Duty Diesel area, the Continuously Regeneration trap has been widely applied in the retrofit market. As the Special act for the improvement of air quality in the capital area, the retrofit program for DPF to used diesel vehicle has progressed favorably and there are currently over 1,000 of these DPF in use in retrofit applications in korea. These DPF comprise a specially formulated Diesel Oxidation Catalyst upstream of a DPF. The $NO_2$ generated by the DOC is used to combust the carbon collected in the DPF at low temperature. To certificate DPF device that is suitable to domestic circumstances, it is necessary to evaluate exactly the DPF devices according to the regulation of DPF certificate test procedure for retrofit(ministry of environment(MOE) announcement NO. 2005-16). To do so the understand of that regulation like the standard of PM reduction rate is needed. In this study the test procedure including test cycle and BPT test condition was examined and also the test result for specific DPF was analyzed. In every test like field test, PM reduction efficiency test and seoul-10 mode test, no defect could be showed.

• Journal of Forest and Environmental Science
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• v.33 no.2
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• pp.113-121
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• 2017

In flight particulate matter particularly emissions generated by incomplete combustion processes has become a subject of global concern due to the health problems and environmental impacts associated with them. This has compelled most countries to set standards for coarse and fine particles due to their conspicuous impacts on environment and public health. This contribution therefore explores forest fire emissions and how its particulates affects air quality, damage to vegetation, water bodies and biological functions as architects for lung diseases and other degenerative illnesses such as oxidative stress and aging. Soot was collected from simulated forest fire using a clean glass surface and carefully transferred into amber vials for analysis. Volatile components of soot were collected over 10 mL dichloromethane and analyzed using a QTOF Premier-Water Corp Liquid Chromatography hyphenated to a mass selective detector (MSD), and Gas Chromatograph coupled to a mass spectrometer (GC-MS). To characterize the size and surface morphology of soot, a scanning electron microscope (SEM) was used. The characterization of molecular volatiles from simulated forest fire emissions revealed long chain compounds including octadec-9-enoic acid, octadec-6-enoic acid, cyclotetracosane, cyclotetradecane, and a few aromatic hydrocarbons (benzene and naphthalene). Special classes of organics (dibenzo-p-dioxin and 2H-benzopyran) were also detected as minor products. Dibenzo-p-dioxin for instance in chlorinated form is one of the deadliest environmental organic toxins. The average particulate size of emissions using SEM was found to be $11.51{\pm}4.91{\mu}m$. This study has shown that most of the emissions from simulated forest fire fall within $PM_{10}$ particulate size. The molecular by-products of forest fire and particulate emissions may be toxic to both human and natural ecosystems, and are possible precursors for various respiratory ailments and cancers. The burning of a forest by natural disasters or man-made fires results in the destruction of natural habitats and serious air pollution.

• Transactions of the Korean Society of Automotive Engineers
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• v.19 no.3
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• pp.52-56
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• 2011

Active regeneration in CDPF requires $O_2$ which regenerates soot at high temperature. However, small amount of NO can interrupt $O_2$ regeneration in CDPF. To verify this phenomena, soot oxidation experiments using a flow reactor with a $Pr/CeO_2$ catalyst are carried out to simulate Catalyzed Diesel Particulate Filter (CDPF) phenomena. Catalytic soot oxidation with and without small amount of NO is conducted under tight contact condition. As the heating rate rises, the temperature gap of maximum reaction rate is increased between with and without 50ppm NO. To accelerate the $NO_2$ de-coupling effect, CTO process is performed to eliminate interfacial contact for that time. As CTO process is extended, temperature which indicates peak reaction rate increases. From this result, it is found that small amount of NO can affect tight contact soot oxidation by removal of interfacial contact between soot and catalyst.

• Journal of Advanced Marine Engineering and Technology
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• v.30 no.1
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• pp.88-92
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• 2006

This study is intended to check the flame temperature to raise in burning grade C heavy fuel oil and emulsion fuel oil in a boiler and to measure the concentration of Dry Shoot(DS) and Soluble Organic Fraction(SOF) after collecting the Particulate Matters (PM). The flames temperature in boiler was measured by burning grade C heavy oil and oil-water emulsion (C heavy oil $70\%\;and\;30\%$ of water) Combustion characteristics of two fuels was also compared by trapping particulate matters (PM) in exhaust gas and measuring the generated quantities of DS and SOF in fuel gas.

• Particle and aerosol research
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• v.19 no.4
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• pp.101-110
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• 2023

In order to reduce particulate matters (PM) from marine diesel engines, we developed novel electrostatic diesel particulate matter filtration system. Electrostatic diesel particulate filtration (DPF) system consists of electrostatic charger and filtration part. The electrostatic charger and filtration part are composed of a metal discharge electrode and a metal fiber filter (porosity: 68.1-86.1%), respectively. In the electrostatic charger part, diesel soot particles are reduced by electrostatic force. The filtration part after electrostatic charger part reduces diesel soot particles through inertial and diffusion forces. The filtration efficiency of electrostatic DPF system was examined through the experiments using engine dynamometer system (300 kW) and ship (200 kW). The PM reduction efficiencies due to inertial and electrostatic forces showed about 70-75% and 80-90%, respectively, according to the RPM of the engine. The differential pressure of the electrostatic DPF system applied to the ship was about 1-9 mbar, which was less than the allowable differential pressure for ship engines in South Korea (100 mbar). The results show that the electrostatic DPF system is suitable for application to the PM reduction emitted from ships.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.3
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• pp.163-170
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• 2016

Regulations for the exhaust gas of diesel vehicles are being strengthened every year. Recently, diesel emission regulations for HC, CO, NOx, and particulate matter (PM) have been subject to very strict standards. In the future, the regulation of PM is expected to become stricter. Accordingly, diesel particulate filters (DPFs) have been applied to most diesel vehicles for PM reduction. With increasing engine mileage, ash and soot from the engine exhaust gas accumulate inside the DPF. This accumulation can damage the DPF or degrade engine performance. Therefore, efficient cleaning of the DPF is critical for the maintenance of the engine. If the DPF is well managed through regular cleaning, it can improve the power and fuel economy of the engine and reduce maintenance costs. Therefore, this study was performed to develop a high-efficiency cleaning method for DPFs and an apparatus that can more effectively clean out the accumulated ash and soot.