(563b) The Influence of Ammonia on Flame Characteristics and Soot Formation in Ammonia/Methane Diffusion Flames | AIChE

(563b) The Influence of Ammonia on Flame Characteristics and Soot Formation in Ammonia/Methane Diffusion Flames

Authors 

Montgomery, M. - Presenter, Yale University
Montgomery, M. - Presenter, Yale University
Kwon, H., Penn State University
Kwon, H., Penn State University
Xuan, Y., Penn State University
Xuan, Y., Penn State University
Pfefferle, L., Yale University
Pfefferle, L., Yale University
McEnally, C. S., Yale University
McEnally, C. S., Yale University
Because of narrow stability limits for the efficient burning of ammonia (NH3), strategies for enhancing the stability of NH3 combustion processes have been pursued, such as through co-firing with hydrocarbons. Under these circumstances soot formation becomes possible, and the influence of NH3 on soot emissions in these technologies becomes relevant. However, there is a lack of studies that have analyzed the effect of NH3 on soot formation pathways and how it ultimately impacts particulate matter emissions. In order to begin answering these questions, we measured the flame structure characteristics and relative soot volume fraction distributions in NH3-CH4 co-flow diffusion flames with varying levels of NH3-blending. We also compared these measurements to those in N2-diluted CH4 flames for reference. Center-line temperature measurements and flame images were taken to determine flame heights and lift-off heights, respectively, and relative maximum soot volume fractions in flames with varying ratios of NH3 and CH4 were measured using line-of-sight spectral radiance. Computational 2D flame simulations were also employed in order to estimate flame lengths, lift-off heights, and distributions of species relevant to soot formation. Experimental and computations results are compared against each other in order to assess the accuracy of the underlying chemical mechanism and begin explaining the soot formation pathways affected by the presence of NH3.