Abstract: A numerical simulation of a dense flow absorber with Fluent software was performed to study the effects of the flue gas rectifier system and the chain agitator on the flow field and turbulent flow of flue gas, the trajectory of circulating ash and the pressure loss of the dense flow absorber. The optimal layout form of the baffle plate was determined under the simulated condition. It is found that the chain agitator obviously amplifies the turbulent kinetic energy inside the dense flow absorber, while the increase of revolving speed cannot obviously improve the whole turbulent intensity of flue gas. The double-deck chain agitator can enlarge the area with high turbulent intensity and retard turbulent dissipation. Under this condition, the desired speed of the double-deck chain agitator is 100 r·min^-1. Meanwhile, the uniform distribution of flue gas inside the dense flow absorber and the gas-solid sufficient contact can be realized, most of particles are involved in internal recycling, and a small quantity of particles enter the dust catcher. The pressure loss of the system is approximately 200 Pa.