• Journal of the Korean Society of Combustion
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• v.9 no.1
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• pp.11-17
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• 2004

The purposes of this study are to analyze nitrogen oxides(NOx) formation mechanism and to reduce abnormal NOx emissions in gas turbines. Industrial gas turbines emissions have potential to negative affect to the atmosphere in many different ways such as photochemical smog, acid rain and global warming. In conventional gas turbine combustors, one of the main pollutants such as nitrogen oxide(NOx) species, are principally formed from combustion process of fuel with oxygen in the primary combustion zone, and their emission levels are highly depend on peak temperatures in the combustor. In order to examine the characteristics and the effect of NOx formation, we used gas turbine of which commercial operating in Korea. From the examination, it has been found that NOx emissions are relatively high at low load(output) and during combustion mode change. Also, the effect of Air/Fuel ratio was considered. As the Air/Fuel ratio was increased in Lean-Lean mode, the NOx emission was decreased. The results of this study indicated that NOx emission levels are highly depend on peak temperature and pressure of combustion process in the combustor.

• Proceedings of the KSME Conference
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• 2004.11a
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• pp.1751-1755
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• 2004

Increasing environmental pressures to reduce NOx emission are being placed on coal-fired boilers. To meet the environmental requirements, Doosan Heavy Industries & Construction Co., Ltd.(Doosan) has developed low NOx pulverized coal burner. Low NOx pulverized coal burner has already delivered, and it's combustion performance was evaluated to the NOx and Unburned Carbon(UBC) during the commissioning tests. The test results are shown that the strong relationship is existed between NOx and OFA flow rate, and also fuel-N fraction of coal has effected on NOx emission.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.46 no.4
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• pp.487-494
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• 2010

In order to test the applicability of bunker-A in a diesel engine for small-fishing boat, the investigation of the engine performance and the exhaust emission was performed under various conditions of fuel property, intake air pressure and fuel temperature. It was also performed based on IMO NOx Technical code. At high load, the energy consumption rate of bunker-A was lower than that of diesel oil, and the characteristics of exhaust emission of bunker-A were similar to those, and NOx emission rates of both fuels satisfied the IMO NOx emission regulation limits. The energy consumption rate and characteristics of exhaust emission were improved as the intake air pressure was increased, but these were not improved remarkably as the temperature of bunker-A was heated. However, at low load the energy consumption rate, CO emission rate and HC emission rate of bunker-A were higher than those of diesel oil, but NOx emission rates of the fuels were about the same. In addition, at low load the energy consumption rate and CO emission rate of bunker-A were increased as the intake air pressure and the temperature were higher than normal conditions. Accordingly, it is thought that the use of bunker-A in a kind of test engine is possible at high load. On the other hand, it is thought that more research is needed to improve the combustion efficiency under low temperature and low load condition.

• Journal of Korean Society for Atmospheric Environment
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• v.22 no.5
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• pp.693-700
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• 2006

The important factor for the development of burner is the achievement of low emissions with maintaining combustibility. In case of maintaining high temperature flame and excess air to increase the combustibility, it is possible to achieve high combustion efficiency, due to the reduction of UHC(unborn hydrocarbon), carbon monoxide and soot. However, it is difficult to reduce the thermal NOx produced in the high temperature flame. To solve this problem, we developed externally oscillated oil burner which is possible for the high efficiency combustion and low NOx emission, simultaneously. The experiment of flame characteristics and NOx reduction were achieved according to the variation of frequency, amplitude and air velocity. Frequency, amplitude and air velocity are the most important parameter. The optimum operating conditions are frequency 1,900 Hz, amplitude 3 $V_{pp.}$ and air velocity 6.8 m/s. Reduction of NOx and CO are 47% and 22%, respectively.

• Journal of environmental and Sanitary engineering
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• v.18 no.2
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• pp.27-33
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• 2003

This survey was performed to investigate the NOx emission factors at 3 Municipal Solid Waste Incinerators(MSWI) and 5 Power generation boilers in Seoul. The NOx concentrations were measured before and after control systems. The results were as follows. 1) The NOx reduction efficiencies of Selective Catalytic Reduction (SCR) using ammonia as reducing agent ranged from 53.7% to 89.9%. The NOx reduction efficiencies of SCR using methanol as reducing agent, Non- Selective Catalytic Reduction (NSCR) using ethanol as reducing agent and low-NOx burner were 20.8%, 29.1% and 24.7%, respectively. 2) The NOx emission factors at A-1, A-2 and A-3 facilities of MSWI were 0.786, 0.127 and 0.594 kg Nox/ton fuel, respectively. The factors of A-1 and A-3 facilities were higher than the average value of Korea. 3) The NOx emission factors at B-1, B-2, B-3, B-4 and B-5 facilities of Power generation boiler were 2.109, 0.726, 4.106, 8.378 and 5.168 kg Nox/ton fuel, respectively. The factors of B-4 and B-5 facilities were higher than the average value of Korea.

• Proceedings of the KSME Conference
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• 2003.11a
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• pp.379-384
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• 2003

Coal-burning utilities are facing a major NOx control compliance challenge due to the heavy emission regulation. In response to this challenge, some applicative technologies to effectively reduce NOx are developed and applied in the pulverized coal power plants. One of these is low NOx burner(LNB) equipped with multi-staged air register. In this study, NOx emission rate and flame shapes are investigated with secondary and tertiary air flow conditions in air staged coal burner, and the optimal windows of flow conditions to minimize NOx emission rate are found out. The test conditions treated in this study are the flow rate, swirl direction and intensity and throat injection velocity of secondary and tertiary air.

• 한국연소학회:학술대회논문집
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• 2003.05a
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• pp.301-310
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• 2003

Eco-Machinery engineering technologies in KIMM for reducing NOx emission were introduced. Combustion technologies such as reburning and fuel staged or air staged combustion have been applied to reduce NOx emission in the field of boiler furnaces. Lean premixed combustion method have been studied in gas turbine combustor. Hybrid system with plasma and SCR being considered as prospective method of De-NOx has been developed. Also, low NOx technologies including common rail system, EGR and DPF in diesel engine have been investigated.

• 한국연소학회:학술대회논문집
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• 2001.11a
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• pp.17-26
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• 2001

Self flue gas recirculation flow is an effective method for low NOx emission in the regenerative low NOx burner. The object of this study is to analyze the self flue gas recirculating flow by varying jet velocity of the combustion air. Fuel and air flow rates are fixed and combustion air jet nozzle diameters are 13, 6.5 and 5mm. The stoichiometric line is obtained from the concentration of the fuel using an acetone PLIF technique. It is found that the self flue gas recirculating flow is entrained into that line using a two color PIV technique. As the jet velocity of combustion air is increased, the flue gas entrainment rate into the stoichiometric line is increased. This result suggests that NOx emission can be reduced due to the effects of flue gas which is lowering the flame temperatures.

• Journal of the Korean Society of Combustion
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• v.6 no.1
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• pp.20-28
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• 2001

Self flue gas recirculation flow is an effective method for low NOx emission in a regenerative low NOx burner. The object of this study is to analyze self flue gas recirculating flow by varying the jet velocity of the combustion air. Fuel and air flow rates are fixed and combustion air jet nozzle diameters are 13, 6.5 and 5mm. The stoichiometric line is obtained from the concentration of fuel using the acetone PLIF technique. It is found that self flue gas recirculating flow is entrained into that line using the two color PIV technique. As the jet velocity of combustion air is increased, the flue gas entrainment rate into the stoichiometric line is increased. This result suggests that NOx emission can be reduced due to the effects of flue gas lowering the flame temperature.

• Journal of the Korean Society for Marine Environment & Energy
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• v.7 no.4
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• pp.174-179
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• 2004

Domestic marine diesel engine makers reduce the NOx emission mostly by applying low NOx fuel nozzle and injection timing retard. However, it is necessary to develop high efficient technology (EGR, DWI and SCR, etc.) to reduce NOx emission in order to prepare for the further reinforcement of the NOx emission limit. Also, in the near future, IMO will restrict additively THC, PM and CO with NOx. Therefore, domestic engine makers have to prepare for it and the relevant government ministries should give a sufficient support to these technology research and establish or amend the relevant law, which should include the excursion riverboat.