Combustion of Pakistani lignite (Thar coal) in a pilot-scale pulverized fuel down-fired combustion test facility

Abstract

In this study, Pakistan’s first and foremost pilot-scale combustion test results of Thar lignite Block-8 have been reported. The reported data will be an addition to the existing literature on lignite firing testing. In this paper, NOx, CO, and CO2 measurements were recorded at different axial locations in a down-fired combustion test facility for 2, 2.3, and 2.6 s of primary combustion zone residence times in a 4 m long down-fired pulverized fuel furnace. The overall NOx and SO2 emissions have also been reported for unstaged and air-staged combustion conditions. The reported data (emissions and carbon burnouts) is for fuel/air stoichiometric ratios of 0.9, 1.01, and 1.16 near the burner zone. The fly ash sample was analyzed, and the percentage of iron oxide was found in the range of 18–21%, whereas the percentage of alumina concentration was in the range of 14–16%, for varying stoichiometric ratios. Furthermore, slagging and fouling analyses have also been carried out on the collected ash samples during testin