Numerical Investigation of Co-Firing of Palm Kernel Shell into Pulverized Coal Combustion

Abstract

Co-firing of palm kernel shell (PKS) into 7 MW existing pulverized-coal boiler has been modeled and analyzed using the computational fluid dynamics (CFD). Co-firing of coal and PKS is a complex chemical reaction involving both gas and solid phases with turbulence effect along the combustor. In numerical simulation, two-steps global reaction mechanisms for homogeneous (volatile matter) and heterogeneous (char) combustion, turbulence and radiation heat transfer are considered. Moreover, five different mass fractions of PKS to coal are observed: 0 (fully coal), 10, 15, 25 and 50 %, respectively. In this study, the analysis is focused on the comparative prediction related to the distribution of temperature, velocity and produced gases of CO2, CO, SO2. As the result, higher PKS mass fraction leads to a favorable combustion in terms of combustion temperature and produced gases exhausted from the combustor.

Numerical analysis of flow and combustion of Coal-Ammonia blend in coal-fired furnace

“…The diminished O 2 levels at the furnace's centre indicated a state of complete combustion for both fuel and air. As the flue gases ascended from the windbox into the rear pass and outlet, a gradual increase in O 2 content was noticed, corresponding to a significant reduction in the combustion of fuel and air, given that a substantial portion of the fuel had already undergone complete combustion [26].…”

“…However, incomplete combustion occurred due to insufficient O 2 , resulting in the production of CO [25]. The CO content gradually decreased as the exhaust gases moved into the rear pass zone, where combustion of fuel and air significantly diminished, given that most of the fuel had already undergone complete combustion [26].…”

“…Therefore, it can be concluded that CO 2 production is highest in areas where the O 2 content is most depleted, particularly in the windbox region. As the flue gases progress upwards from the windbox through the rear pass and into the outlet, the CO 2 concentration decreases due to diminished combustion of fuel and air, as much of the fuel has already undergone complete combustion [26].…”

Analysis of Biomass Waste Cofiring into Existing Coal-Fired Power Plant Using Computational Fluid Dynamics

“…Related to cofiring using CFD analysis, it is expected that the combustion performance for all stages of the combustion including the combustion temperature, kinetic behavior, and concentration of the produced gases can be clarified. Cofiring simulation considers dynamical equations, conservation of mass (continuity), momentum and enthalpy, turbulence, radiation heat transfer, and reactions in both particle and gas phases [10].…”