• 한국연소학회:학술대회논문집
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• 2006.04a
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• pp.121-127
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• 2006

It has become inevitable to search for alternative fuels due to severe energy crisis these days. Use of alternative fuels, which are typically of lower quality, tends to increase environmental pollution, including formation of nitrogen oxides (NOx). In this paper performance of vacuum residue has been investigated experimentally as well as numerically in typical operating conditions of a furnace. Heat release reaction is modeled as sequential steps of devolatilization, simplified gas phase reaction and char oxidation as that for pulverized coal. Thermal and fuel NOx are predicted by conditional estimation of elementary reaction rates and are compared against measured experimental data. On the overall reasonable agreement is achieved for spatial distributions of major species, temperature and NOx for all test cases.

• Journal of Power System Engineering
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• v.6 no.2
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• pp.12-17
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• 2002

Recently, the world is faced with very serious problems related to the air pollution due to the exhaust emissions of the diesel engine. So, many of researchers have studied to reduce the exhaust emissions of diesel engine. This study was investigated for various exhaust emissions according to operating conditions in a turbocharged D.I. diesel engine. As a result of experiments in a test engine, the $CO_2\;and\;NO_x$ increased with increasing load, the $CO_2$ and CO decreased with increasing charge air pressure in manifold, the CO decreased with increasing cooling fresh water temperature, and the $NO_x$ decreased with worming cooling fresh water before engine start.

• Transactions of the Korean Society of Automotive Engineers
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• v.5 no.6
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• pp.120-127
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• 1997

A diesel engine is one of the major prime movers owing to its high thermal efficiency. But due to the recent attention for the environmental pollution, the emissions of diesel engine became a important problem. So it is needed to understand the characteristics of diesel spray injected into a combustion chamber. Because the diesel combustion is strongly controlled by a fuel spray injected into a combustion chamber. This study provides the informations for the diesel spray with the atmospere condition in combustion chamber by PMAS. As the result, the spray tip penetration and angle is increased with the increase of spray pressure and nozzle diameter. And the comparisions between the measured outline of the free-spray and the calculated model have been conducted and obtained the resonable results.

• Proceedings of the KIEE Conference
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• 1997.07c
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• pp.1088-1090
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• 1997

This paper presents an effective methodology of optimal environmental and economic operation using evolution strategy. In power systems, evolution strategy, based on natural selection and genetics, can analyze non-linear and discontinuous functions in global search techniques. The formulation using this search techniques is multi-objective function, which consists of fuel cost and environmental effects concerning the pollution of the Earth's atmosphere caused by the emission of $SO_2$ and $NO_x$ from thermal generator plants. The proposed algorithms are applied on system with 6 generator.

• International Journal of Advanced Culture Technology
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• v.3 no.1
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• pp.78-85
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• 2015

In Thailand, the electricity consumption is very high with the intention of reduce high temperature in the building. Since 2000, a lot of people paying attention to Green-Building concept. A similar concept is natural building, which is usually on a smaller scale and tends to focus on the use of natural materials that are available locally. Therefore, the Earth-Block (EAB) product is appropriated approach to reduce energy consumption in the buildings. The EAB is produced with environmentally friendly process, which does not release harmful pollution and effective cost. The main significant character is durable materials for building construction. This study aims to develop the new thermal insulation by using soil-cement with vetiver grass fibre. Additionally, it describes the innovative systems used in production of EAB materials by mixing the soil-cement with vetiver grass fibre. This paper reveals lowest costs, space configurations changing and greater design flexibility for constructing the building.

• Membrane Journal
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• v.8 no.3
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• pp.117-129
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• 1998

The atmospheric pollution by diesel emission is mainly attributed to particulate matters and NO$_x$. Their regulation limits have become tighter. This paper reviews the characteristics and the fabrication method of the diesd particulate filter(DPF) which is used to control the particulate matters of diesel emission. First the constituent of particulate matters and the regulation standard are discussed and then the state of the art post-treatment system is reviewed. The materials, the fabrication method and the control of thermal expansion of the ceramic honeycomb filter, which is widely used as the DPF, are also reviewed.

• Journal of the Korean Applied Science and Technology
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• v.21 no.4
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• pp.352-358
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• 2004

The firing reaction and calcination characteristics of the waste shellfish were examined for the future use as absorbent. The weight variation was measured according to thermal-decomposition using TGA and observed variation of the phase. The qualitative and quantitative analysis of the sample were performed using XRD and the structural analysis, SEM. The results of TGA and XRD experiments showed that the almost all of the raw Corbicula Japonica and Ostrea virginjca were changed from calcite to lime by firing and calcination reaction. The result of SEM experiment showed that the plate type of the raw sample was changed to circle type, so the surface area ratio was increased. Above results suggested that waste shellfish were usable as absorbent in the viewpoint of the reuse of resource and the decrease of environmental pollution.

• Proceedings of the Korea Concrete Institute Conference
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• 2005.05b
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• pp.457-460
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• 2005

The stone powder sludges, which are occurred in aggregate production company, have classified the specified waste, so taking place the environment pollution and the disposal cost. In this causes, the stone powder sludge is required the development of recycling technique. This study concerned with the using possibility of stone powder sludge on light weight concrete. We acquired the fundamental date on recycling technique of stone sludges, by hydro-thermal reaction. The results shows that it is possible to develop the light weight concrete, having various range of properties according to the content of foam.

• Journal of the Korean Society of Safety
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• v.16 no.3
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• pp.41-44
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• 2001

The removal characteristics of nitrogen oxides (NOx) by the dielectric ($Al_2O_3$) packed-bed plasma reactor are experimentally investigated Reactor is packed with 5[mm] diameter $Al_2O_3$ beads, and was desisted to remove NOx at atmospheric pressures from the moving pollution source such as diesel automobile. The experiments were conducted for applied voltages from 5 to 10[kV], flue gas rate from 2 to 5[l/min] and frequency from 0.5 to 2[kHz]. The NOx removal efficiency significantly increasing with increasing applied voltage. Especially removal rate significantly increased with increasing frequency. However, in this experiment discharged poler n relatively high.

• Journal of Advanced Marine Engineering and Technology
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• v.24 no.4
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• pp.454-459
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• 2000

Diesel engine which has high thermal efficiency is one of the major movers. Recently, as people pay attention to the environmental pollution, the emission of Diesel engine becomes an important problem. So it is needed to understand the characteristics of diesel fuel spray injected into a combustion chamber to reduce the emission. The factors which control the diesel fuel spray are the injection pressure, the nozzle diameter, the impinging angle and the variation of an ambient pressure and temperature. In this paper, the experiments were conducted in the free spray and the impinging spray with various ambient temperatures(273K, 373K, 573K). And the behaviors of the diesel fuel spray, such as penetration, spray angle and axial distance in the free spray and axial distance and spray thickness in the impinging spray were studied.