Simulations of pulverized coal oxy-combustion in swirl burner using RANS and LES methods

• Oxy-combustion process has been modeled with simplified coal devolatelization model.
• Oxy-combustion process has been modeled with simplified char combustion model.
• Comparison of oxy and air combustion process of pulverized coal has been done.
• Comparison of RANS and LES results for pulverized coal combustion has been done.

Oxy-combustion is a technology that is used to reduce the emission of greenhouse gases to the atmosphere. Adaptation of the existing systems to burn coal in oxy-combustion technology requires a number of studies that can be greatly supported by numerical investigations — computational fluid dynamics (CFD). The paper presents results of pulverized coal combustion process in swirl burner using RANS and LES methods for turbulent flow. Numerical simulations have been performed for oxy-combustion technology for various ratio of oxygen in the oxidizer and compared to conventional combustion in air. Comparison of the air and oxy-coal combustion process for pulverized coal shows significant differences in temperature, especially the temperature close to the burner exit. In order to represent the conventional coal combustion process, oxidizer should contain about 30% of oxygen in the O2/CO2 mixture.