Soot emissions (PM 2.5) from land-based sources pose a substantial health risk, and now are subject to new and tougher EPA regulations. Flaring produces significant amount of particulate matter in the form of soot, along with other harmful gas emissions. A few experimental studies have previously been done on flames burning in a controlled condition. In these lab-experiments, great effort is needed to collect, sample, and analyze the soot so that the emission rate can be calculated. Soot prediction in flares is tricky due to variable conditions such as radiation and surrounding air available for combustion. Work presented in this paper simulates some lab-scale flares in which soot yield for methane flame mixture was measured under different conditions. The focus of this paper is on soot modeling with various flair operating conditions. The computational fluid dynamics software ANSYS Fluent 13 is used. Different soot models were explored along with other chemistry mechanisms. The effect of radiation models, quantity of air supplied, different fuel mixture and its effect over soot formations were also studied.
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