Determination of optimally feasible operating parameters for gasification of high-ash-content coal

Abstract

The use of the coal in power generation poses serious issues of particulate emissions and efficiency limitations. Power generation through a gasification route is a potential eco-friendly method. However, the gasification of high-ash-content coal itself is a major challenge, as the presence of high ash content (> 40%) limits the rate of reaction and leads to flow resistance, significantly affecting the gas quality. To overcome this limitation, one has to determine the optimal feasible operating parameters for its gasification. In the present investigation, a two-phase equilibrium model is used to determine the optimally feasible range of the equivalence ratio for gasification of five different types of coals whose ash content varies from 41.08 to 52.56% on a dry weight percentage basis. A parametric study is also carried out with respect to enriched O_2 air and steam addition to find the optimal process configuration. Moreover, response surface methodology is used to optimize the operating variables. From the analysis, it is finally observed that for high-ash-content coals, the most optimally feasible operating parameters are the use of 26.5% O_2-enriched air with 10% mass addition by steam. Graphical abstract