Chapter 12 - Influence of alcohol and gaseous fuels on NOx reduction in IC engines

Abstract

Automotive vehicles operated with conventional fuels lead to increasing exhaust gases and reduced crude oil availability. In particular, NOx emissions from automotive engines fueled with fossil fuels are major pollutants of the environment. To diminish these effects, stringent norms enacted by various countries have led to the identification of significant techniques. For that, blending or complete replacement of alcohol and gaseous fuel with fossil fuel is an effective technique. This chapter discusses the ability of various alcohol and gaseous fuels as blends or alternates for fossil fuel to control NOx emissions. Also, it provides a comparative analysis of the physicochemical characteristics of alcohol and gaseous fuels with fossil fuels. Even a minor variation in the alcohol and gaseous fuel is sufficient to make changes in the combustion process, which will affect NOx formation. These increasing and decreasing effects of NOx related to various properties of alcohol and gaseous fuels are provided in separate tables. Generally, the NOx decrease has been done with alcohol fuels. But with hydrogen and compressed natural gas (CNG), NOx reduction has not been attained with all operating and blending conditions. Moreover, the reduction of NOx in alcohol fuels can be attained only by using appropriate blending ratios or mixing proportions. Finally, this chapter discusses the characteristics and various compositions of fuel that affect NOx formation.