Estudo da formação de poluentes via simulação numérica de modelos cinéticos de frações da gasolina

Abstract

The increase in the use of biofuels is not only a solution to replace the energy mix based on oil, but has also been adopted by the ability to minimize emissions of air pollutants by combustion processes. However to make such types of changes, it is necessary to perform a detailed study of the potential impacts related to these changes. Many studies have been conducted in order to understand the behavior of biofuels when blended to gasoline. It was observed the reduction in concentrations of particulate matter (PM) in the fraction of PM10, however there was an increase in particles with diameter smaller than 2.5 μm. which present higher toxicity than PM10 particles. In this study was evaluated the main pollutants formed during the combustion process of the ethanol-gasoline mixture by kinetics models of gasoline combustion. The used and proposed model is composed by four models: the Mehl s mechanism for gasoline combustion (Mehl et al., 2012), the combustion model of ethanol and n-butane that includes the formation reactions of polycyclic aromatic hydrocarbons (PAH) of Marinov et al., (1998, 1998), and the reaction for nitrogenated compounds proposed by Hori et al., (2008). The proposed model was validated by comparison of ignition delay time calculated by the simulations with the equation proposed by Cancino et al., (2011). The model predicts the formation of fluorene and fluoranthene as the major PAH formed during combustion. The evaluation of the effect of ethanol addition in the gasoline indicates the increase of CO concentration and decrease o NOx concentration as the ethanol concentration increase