Computational Simulation of Gas-Solid Flow to Reduce Erosion in a Circulating Fluidized Bed (CFB) Boiler

Abstract

Circulating fluidized bed (CFB) is one type of coal combustion technologies that plays an essential role in the power generation. CFB boilers use the principle of the thermal inertia of material deliberately inserted into the furnace (known as bed materials) which is usually sand particles. The existence of materials in the form of particles with high speed can lead to erosion on the wall furnace. The amount of erosion in the furnace wall is influenced by the speed and flow pattern as well as the particle shape of the particle. This paper performed three-dimensional simulations of a CFB boiler using CPFD software to determine the behavior and location of erosion on furnace modelling and simulation. A computational particle fluid dynamics model of a pilot-scale circulating fluidized bed (CFB) was used to simulate its gas-solid flow characteristics numerically. The accuracy of the model was confirmed by a comparison of the simulation results with the operation data. Decreasing the operating parameters according to the calculation of stoichiometry reactions shows a decrease in erosion, thereby making CFB boiler more reliable. Furthermore, the simulation result provide a reference for further comprehension of the flow characteristics in CFBs.