Keywords: Fourier-transform infrared photoacoustic spectroscopy, loss-on-ignition, unburned carbon
Relationships among loss-on-ignition and unburned carbons, and the FTIR photoacoustic spectra of fly ashes
Loss-on-ignition (LOI) and unburned carbon (UC) concentrations of fly ash are two very important indices for evaluating combustion efficiencies of boilers. They are also very important factors affecting the utilisation of fly ashes. The LOI and UC of five fly ash samples collected from different power plants were analysed. The Fourier-transform infrared (FTIR) photoacoustic spectra (PAS) of these fly ash samples were observed. The LOI and UC of fly ashes were found to correlate with the heights of the baselines of their FTIR PAS. The strength of the photoacoustic signal of fly ash has a stronger relationship with its UC than its LOI. Moreover, the LOI of fly ash is always higher than its UC.