G. A. Ryabov, O. M. Folomeev
Circulating fluidized bed (CFB) plants are widely used in energy, petrochemicals, aluminum production and other industrial sectors. The CFB technology is characterized by relatively high reactor velocity that exceed the transport velocity of medium-sized particles, and the presence of separators (mainly of the cyclone type) with a recirculating system for returning trapped particles to the reactor. In fact, it is the cyclone capture efficiency that directly determines the multiplicity of circulation and the flow rate of circulating particles and their size characteristics. The dependence of the correction on the mass concentration of particles is proposed. A brief description of the test rigs and the results of our own studies of particle separation in cyclones are given. Experimental data on the effect of dust on the capture efficiency are presented in the form of a dependence of the relative entrainment of particles (1-efficiency) on the mass concentration of particles at the entrance to the cyclone. Recirculating systems consist of downpipes equipped in the lower part with pneumatic valves for transporting material from the low (atmospheric) pressure zone in the cyclone to the high-pressure zone in the furnace. Pneumatic valves operate on the principle of fluidized valves, and the locking function of the valves is performed by a lifting section with an inclined return flow to the furnace (loop gate or J-valve) or a horizontal section connecting the drain to the furnace (L-valve). The report discusses the current state of development and methods for standpipe and pneumatic valve operation and calculating. The results of the work can be used for the design and commissioning of a circulating fluidized bed reactors, including systems with dual reactors for polygenerating systems and chemical looping.
circilated fluidized bed, hydrodynamics, solids separation efficiency pressure drop, recicrulating systems, down flow behavior, pneumatic valve
Cite this paper
G. A. Ryabov, O. M. Folomeev. (2021) The Influence of Particles Flow Rate on Separation and Pressure Drop in Cyclones and Down Flow Behavior in Recirculating Systems. International Journal of Environmental Science, 6, 477-485