Fuel and Combustion

Fuel and Combustion

Experimental Study of Natural Gas Temperature Effects on the Flame Luminosity and NO Emission in a 120 kW Boiler

Authors
Seyed Mohammad Javadi
Mohammad Moghiman
Faculty of Engineering, Department of Mechanical Engineering, Ferdowsi University of Mashhad, Mashhad, Iran
Abstract
In gas-fired furnaces, the flame radiation enhancement significantly improves the radiative heat transfer, which in turn reduces flame temperature and NO emission. In this paper, the effect of inlet natural gas preheating on the flame luminosity and overall efficiency in a 120KW boiler are investigated experimentally. Flame radiation is measured by use of laboratory pyranometer with photovoltaic sensor. A Testo350XL gas analyzer is also used for measuring the temperature and combustion species. The experimental measurements show that the effect of increasing inlet gas temperature on flame luminosity is increased abruptly for temperatures over 240°C. This luminosity increase has considerable effects on flame temperature and NO emission reduction and enhances the boiler efficiency. The results also show that increasing the inlet gas temperature from 240°C up to 300◦C increases the flame luminous radiation by 60%. The obtained results are in desirable accordance with finding of other studies regarding fuel preheating.
Keywords
Fuel preheating
Flame luminosity
Maximum temperature
NO emission
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