Design And Performance Study Of Circular Reflux Dynamic Cyclone Separator

For the demand of efficient dust removal of the coal bed methane, according to the actual working conditions, with comprehensive comparison and analysis of the existing dedusting technology, using the experience of the relevant research results of cyclone separation in recent years, we improve the structure of the traditional static cyclone to design the circular reflux dynamic cyclone separator. The new dynamic cyclone separator contains active rotating parts, through the acceleration of rotating impeller rotation to drive the gas, removing particles in the vortex process of inside and outside two layers, completed two stage separation, and eventually exhaust clean gas. Primary separation process remove particles directly to the ash storehouse, and secondary separation process remove particles through circular reflux line back to the ash storehouse to complete the separation process. Two stage separation process ensure that the short circuit flow and existing problems of static cyclone separator are completely ruled out, and it will improve the processing efficiency of the equipment.In this paper, we use three-dimensional modeling software Pro/e to establish numerical simulation model, and Gambit software to discrete it. Using CFD method, through a combination of RNG k-ε two equations turbulence model, multiple reference frame (MRF) model and DPM discrete phase model, we performed numerical simulations of the continuous phase flow field and the movement of discrete phase particles. We make research through changing the structure of the equipment model parameters such as center rotating drum structure, the structure of the rotating impeller, cone angle of the separator and operating parameters such as operational capacity, speed of the rotating impeller to explore their effects on the performance of the separator, and to optimize its structure.We process a prototype and build experimental platform. We can verify the new dynamic cyclone performance by simulating the operation of equipment under different conditions in which we will change the appropriate structure parameters and operating parameters of the equipment and comparing the experimental results with the conclusions of numerical simulation.It can be drawn through numerical simulation and experimental study:the circular reflux dynamic cyclone separator can effectively remove more than5μm particles in the two-stage separation through reflux dust exhaust and other measures, and the overall efficiency of5μm is more than95%. For particles above10μm, the efficiency is close to100%. The pressure drop of the equipment raises with the increase of treatment capacity and impeller speed, and it reduces slightly with the decrease of the cone angle. The pressure drop of straight type center rotating drum model is greater than diverging type. And the pressure drop of rotating impeller with backward bent vane model is higher than the backward sideling vane model and higher than the straight vane model.The numerical simulation and experimental results show that circular reflux dynamic cyclone separator can basically meet the coal bed methane dedusting requirements of high efficiency, low resistance and anti-fluctuant abilities.