Particle Distribution And Wear Characteristics Research In Liquid Solid CFB

The liquid-solid CFB heat exchanger can prevent fouling depositing on the wall effectively depending on the particle collisions and the scouring wear with the wall constantly. Therefore, the particle distribution and wearing character research in the CFB become one of the hot spots of the heat exchanger surface fouling preventing.First according to the actual structure of single-tube CFB, the research to 90°bend in particle distribution and wearing character has conducted using the discrete phase model. When particles curved pipe flow, the bend place particles concentrated in the outboard wall; Along with the axial increase, the particles mainly distributes in the vertical pipe center, the particles speed near the wall area is lower than the tube center, the wall surface's collision probability decreases, the wear rate reduces; The wear rate of the external wall increases with the fluid velocity and mass flow rate increases, but increases with the particle size decreases; and across the comparison and the analysis to the different angles of particle distribution, it obtained that 90°elbow piece's overall performance was best. Meanwhile, the particle distribution has conducted the experimental study to the vertical pipe, the simulation results and the experimental data agree well, it confirms the applicability of the model and also provides certain reference for the particles on fouling preventing in multiphase fluidized bed.Secondly based on the multi-tube liquid-solid fluidized bed heat exchanger's actual structure, it simulates and analyses the particle distribution in the heat exchanger. The existence of particles causes the liquid phase flow field change, compared with the single phase, the liquid turbulent degree increases obviously; The different structure of heat exchanger, from top to bottom and all the same cone angle of 60°, the particle distribution in the heat exchanger bundle is uniform, the results provide certain theoretical foundation for the particles uniform distribution.