Study Of Effect Of High Temperature Seperator On Hydrodynamices In CFB Boiler Furance

As one of the most mature combustion technologies, Circulating Fluidized Bed (CFB) technique is facing a main trend of maximization. And it leads to certain problems, and the structural-related ones are of the major. As the scales of CFB device are large, experimental research is difficult to perform. Numerical simulation has become a common method to study the gas-solid two phase flow in CFBs. Different arrangement of the positions of the cyclone separators are considered to study the influence to the flow process. Fluent software is used for simulation.The flow characteristics of gas and particles in a HG-670t/h CFB boiler are simulated. In order to reflect practical situation objectively, the geometry size of the CFB used in simulation is the same as its actual size .The results show that different arrangement of the positions of the cyclone separators have great influences on the distributions of velocity, particle concentration and pressure in the furnace. On the basis of analyzing the different cases, we can know whether they are good or not for the operation of the CFB.The result shows the particle velocity turns down along with the height increases. The maximum of particle concentration appears at the bottom. Second-air causes the higher particle concentration in the middle part.Simulations are carried out on different structure models of CFB to study the influent to the particle-gas flow. Cyclone separators are placed on front and rear wall, side wall and unilateral wall. Parameters such as velocity, concentration and pressure of particles are gained. Gas pressure drops along the height. The Porosity reaches the top point at the exit of the cone. Conclusion is draw that the position of cyclone separator is important to the flow process inside the bed.Results of different structure models of CFB provide the reference opinions to the design and modification engineering in practical industry.