Chemical Composition of Submicrometer Particulate Matter (PM1) Emitted from Combustion of Coals of Various Ranks in O2/N2 and O2/CO2 Environments

Abstract

A laboratory-scale investigation has been conducted on the physical and chemical characteristics of particulate matter emissions (ashes) from pulverized coals burning in the air or in simulated oxy-fuel environments. Oxy-fuel combustion is a process that takes place in O2/CO2 gases, using an air separation unit (ASU) to supply the oxygen and a flue-gas recirculation (FGR) stream to supply the carbon dioxide to the boiler. In order to investigate the effects of the background gas on the particulate matter generated by the combustion of coals of different ranks, a bituminous, a sub-bituminous, and a lignite coal were burned in an electrically heated laminar-flow drop-tube furnace (DTF) in both O2/N2 and O2/CO2 environments (21% < O2 < 60%). A recent publication by the authors reports on the physical characteristics of the particulate matter; hence, this work focuses on the chemical composition, specifically targeting the difficult-to-capture submicrometer size (PM1) ashes. Particulate matter was collected b...