Spectral energy characteristics of radiation in oxy-coal combustion for energy utilization

Abstract

In this paper, the radiative energy characteristics, especially the spectral distribution characteristics, of the oxy-fuel combustion of pulverized coal are studied from the perspective of radiative energy utilization. Based on a modified tube furnace test platform, the radiative energy flux and spectral distribution of oxy-fuel combustion for three typical Chinese coals under O2/N2 and O2/CO2 atmospheres in the temperature range of 600–1000 °C are measured online using radiative heat flux sensors. In particular, the radiative exergy and its spectral distribution characteristics are analyzed based on the second law of thermodynamics. It is found that the intensity of the radiative energy and exergy increase, as does the proportion of spectral radiation below the wavelength of 4.1 μm, with the increase of the oxygen ratio and combustion temperature under the experimental conditions. In contrast, different atmospheres are found to have little effect on the radiation characteristics. One-dimensional calculation cases of media radiation transfer constructed according to the combustion characteristics can better reveal the proportional characteristics of the spectral radiation. The results provide a reference for research on the cascade conversion and management of photo-thermal energy in fuel combustion.