Influence of carbon dioxide content in the biogas to nitrogen oxides emissions

Abstract

Fuels derived from biomass are an alternative solution for the fossil fuel shortage. Usually this kind of fuels is called low calorific value fuels, due to the large proportion of inert components in their composition. The most common is carbon dioxide, and its proportion in biogas can be different, from 10 up to 40%, or even more. The presence of inert component in the composition of biogas causes the problems that are related with flame blow off limits. One of the possibilities for efficient combustion of biogas is the combustion in swirling flow including a pilot burner, aimed to expand the borders of stable combustion. This paper presents an analysis of the influence of the carbon dioxide content to the nitrogen oxides emissions. Laboratory biogas was used with different content of CO2 (10, 20, 30 and 40%). Investigation was carried out for different nominal powers, coefficients of excess air and carbon dioxide content. With increasing content of carbon dioxide, emission of nitrogen oxides was reduced, and this trend was the same throughout the whole range of excess air, carried out through measurements. Still, the influence of carbon dioxide content is significantly less than the influence of excess air. The coefficient of excess air greatly affects the production of radicals which are essential for the formation of nitrogen oxides, O, OH and CH. Also, the results show that the nominal power has no impact on the emission of nitrogen oxides

Analysis of the Correlation between Combustion Products in Biomass Thermal Power Plant Using Association Rule Mining

“…The authors of [23] showed that CO occurs due to low combustion temperature, while the low level of NO x is caused by a small percentage of nitrogen in straw and optimal combustion temperature. Furthermore, the authors of [24] showed that, with the increase in CO 2 , the emission of NO x is reduced and the authors of [22] showed that the concentration of NO can be reduced with a higher concentration of SO 2 . In addition, the low levels of NO x can be achieved by coupling the DeNO x catalyst with urea to construct an in-situ NH3-SCR system during the combustion process, as discussed in [25].…”