Research On Air Core Characteristics And Structure Optimization Of Gypsum Cyclone In Power Plant

Gypsum cyclone is an important equipment of wet flue gas desulfurization system (WFGD) in power plant, it's main function is concentration and classification of gypsum slurry from absorber tank and the final production is widely used in cement and construction field. The operation of WFGD system will be disturbed and the quality of final gypsum will be affected because of the serious problems as air core and fish-hook in cyclone's operation. Therefore, it's very important to have a correct understanding of the flow characteristics in cyclone, and it's imperative to design new and efficient cyclone.The flow mechanisms of hydrocyclone were studied. In addition, the performance tests of gypsum cyclone with different structures were carried out in order to deserve the variation of indicator parameters, such as split flow ratio, underflow density, discharge style and so on, the classification efficiency curves with different structures were compared and analyzed, and the reasons of fish hook phenomenon were discussed.Air core is an inevitable problem in hydrocyclone, it's shape and diameter always changed in cyclone's operation. It may cause some problems such as:waste of energy, unsteady flow condition, lower separation efficiency and so on. The development process of air core were simulated with RSM and VOF model by Fluent. The simulation results contained certain aspects of the velocity and pressure distribution, the diameter of air core on different axial position, and the energy consumption, et al.A new style of central solid rod with a conical shape was designed aimed at eliminating the air core and imp roving the performance of gypsum cyclone. Experiments were conducted in order to have a further understand about the negative influences by air core. At the same time, the performances of gypsum cyclones with different central solid rod include production capacity, concentration of underflow, solid-containing content in underflow and particle size distribution were measured and compared, the effects on above-mentioned parameters by inlet pressure were studied also. A simple calculation of energy consumption with different central solid rods indicate that:the energy consumption can be reduced about13.41%with conical central solid rod.A new inlet with separation block and bulkhead was designed in order to improve the classification efficiency of gypsum cyclone. The trajectory of particles in new inlet were simulated with Discrete Phase Mode by Fluent, the effects on particles with different inlet structures and velocity were discussed also. The change of characteristics about gypsum cyclone with different inlet structures were tested by experiment, the results indicate that:there is an apparent improvement of classification efficiency about medium-grained particles.