Aiming at the problems being that the return system and cyclone separator of a circulating fluidized bed boiler fail to achieve the expectation in the actual operation process

thus the CPFD-based Barracuda software was used to conduct numerical simulation to study the influence of different bed particle size and feedcoal bias setting on the stable combustion of the boiler and the imbalance of cyclone separator. According to the result: the oversized particle tend to slag and has done a bad job in particulate fluidization and inner circulation in the furnace

as well as fail to achieve a good distribution of the dilute-phase zone and dense-phase zone. The particle size of the pulverized coal has an important effect on the combustion in the circulating fluidized bed. With different entrainment capacity of the pulverized coal

different particle sizes would have great influence on the combustion simulation in the furnace. The larger the particle size is

the smaller the entrainment capacity of the pulverized coal is

resulting a higher temperature in the upper dilute phase region. The most effective bias setting from left to middle to right is 1.93

2.93

3.93 kg/s respectively.