Using bi‐reforming of methane in natural gas burners: A novel environmentally friendly method for enhancement of thermal properties of flame

Abstract A novel interesting method based on bi‐reforming of methane was proposed for improvement of flame thermal characteristics and radiation heat flux (RHF) in natural gas (NG) furnaces. In the proposed plan, bi‐reforming was done by recirculation of the flue gas. The recirculated flue gas which dominantly including CO 2 and H 2 O and inert gas N 2 mixed with a certain part of NG flow and the mixture passed through an array of nickel based catalysts placed inside a helical tube mounted in the furnace wall to bi‐reforming process is done. Gasses mixture temperature of 800°C, p = 1 atm and the ratio of CH 4 /(CO 2 + H 2 O) = 0.8 were the proposed bi‐reforming condition. The results indicated that in the proposed bi‐reforming condition, significant portion of CH 4 and CO 2 converted to H 2 and CO. The CH 4 and CO 2 conversion were 98.47% and 81.18% while the yield of H 2 and CO as the target reaction products were 94.40% and 93.38%, respectively. Bi‐reforming changed the NG flame from blue to a yellow luminous. Furthermore, since the methane adiabatic flame temperature at p = 1 atm is greater than that of for hydrogen, H 2 generated by bi‐reforming combusted inside the combustion reaction zone and raises the flame temperature. Both enhance the flame temperature and luminosity raises RHF as much as 30%. Finally, although the bi‐reforming slightly increases the NO x emission, it decreases the total amount of flue gas emission to environment, which makes the method environmentally friendly.