The Effect Of Feeding Capacity Ratio To Air Densemedium Fluidized Bed

The air dense medium fluidized bed could deal with grade size of-50+6 mm coal efficient. However, under the constraints of separation efficiency and sorting time, the feeding quantity and property should be limited within a certain range. To obtain highly and stable separation results, the dense phase similar fluid environment in the fluidized bed should keep dynamic stability. Therefore, the feeding disturbanse to the fluidization and separation characteristics in the fluidized bed need to be studied, the feeding quantity and property interval under a certain time with satisfactory separation results need to be tested.The particle flow around impact to the fluidized environment of gas-solid fluidized bed was analysised from particle flow theory. The analysis suggests that compared with pure dense medium flow environment, stream surface area of particles is high pressure zone, the flow back side of particles is low pressure area, in addition turbulent wake region and fluidization dead zone will alternating appeare at the flow back side of particles. Model particles with size of-50+6 mm was used to measure the fluidized environment changes of the area near single particle, the results coincide with analysis of particle flow around. The settlement of differernt density particles in the fluidized bed was analysised from the statistical point of view. The analysis suggests that the surface light product quantity had an significant impact on the settlement of heavy particles, the rules of free settlement and interference with clay of-50+6 mm mineral particle was measured by spark timer.Tracer particles materials with grain size of-50+25 mm,-25+13 mm,-13+6 mm was prepared based on Yujialiang long flame coal. The change rule of fluidization characteristics in fluidized bed under pure heavy medium and add coal feedings with different properties was studied. A simplex lattice design was used to measure the change of separating characteristics under different feeding quantity and properties. A calculation formula of the fluidized bed capacity was put forward between with machine structural parameters and coal feeding properties. As for the coal used in the test, the appropriate capacity limit of the fluidized bed at different machine parameters was figured up.