Optimization of the Outlet Flow Ratio of Mini-Hydrocyclone Separators Using the Full Factorial Design Method to Determine the Separation Efficiency

Cyclone separators are widely used to eliminate particles flowing through pipelines in equipment from various industrial processes. Unlike general filters, cyclone separators can constantly and effectively eliminate foreign substances present in the fluid flowing through the equipment. In this study, we fabricated mini-hydrocyclone separators using the 3D printing method for application in the steam and water analysis system (SWAS) in a thermal power plant instead of the conventional strainer filter. The gravimetric method was used to measure the separation efficiency of the hydrocyclone separators and compare the weights of the sludge discharged from the underflow and overflow outlets. The outlet flow ratio was optimized by adjusting the diameters of the spigot and vortex finder of the separators, which influenced the outlet flow rate. To apply the gravimetric method more objectively, the optimum values of the diameters of the vortex finder and spigot with an outlet flow ratio of 1 were determined using full factorial design (FFD) in the design of experiments (DOE). The obtained values were verified through numerical analysis using the ANSYS Fluent software. Furthermore, after fabrication of the mini-hydrocyclone separators using an SLA-type 3D printer, we conducted a numerical analysis, and the results were compared with that of the actual experiment. It was observed that the use of FFD can effectively optimize the desired outlet flow ratio in the mini-hydrocyclone separator. In addition, the changes in the outlet flow ratio do not affect the separation efficiency of the cyclone separators.

Optimization of hydrocyclon for phosphatic rock separation using CFD

Hydrocyclones are equipment for the separation of solid-liquid and liquid-liquid mixtures through the centrifugal flow. The phosphate rock is an essential raw material to the industry of phosphate fertilizers. The mineral needs to be concentrated in its processing, and this can be done through hydrocyclones, considering its robustness and low operation costs. This work aimed to use the computational fluid dynamics to study different multiphase models to represent the hydrocyclones, as well as modifications to its geometry to increase its efficiency. Three multiphase models were studied in order to analyze their efficiency in simulating the separation through hydrocyclones: Eulerian-Lagrangian, Eulerian-Eulerian, and Mixture Model. In order to optimize the separation process and reduce operating costs, 11 modifications were proposed in the geometry of HC11, called B1, B2, B3, C1, C2, C3, D1, D2, E1, E2 and E3. The first 8 proposals involved changes in the vortex finder and the last 3 proposals added a wall in the air core formation region. Geometry and mesh were generated in the GAMBIT® software and the simulation was made in the FLUENT® 19.2 software. In order to compare the multiphase models, the individual and overall efficiency were used along with the experimental results. The Mixture model had the smallest relative error and was used for the subsequent simulations. The parameters evaluated to measure the optimization of HC11 were the pressure drop (?P), the liquid ratio (RL) and the overall efficiency (?). The results obtained for each of the proposals were compared with the value found in the HC11 simulations to evaluate the possible optimization. With that, it was possible to verify that modifications B2, B3, and D1 improved all the parameters evaluated, optimizing the separation process and reducing energy costs involved in the operation.

Influence of Vortex Finder Structure on Separation Performance of Double-Overflow Three-Product Hydrocyclones

In view of the difficulty of traditional hydrocyclones to meet the requirements of fine classification, a double-overflow three-product (internal overflow, external overflow and underflow) hydrocyclone was designed in this study. Numerical simulation and experimental research methods were used to investigate the effects of double-overflow flow field characteristics and structural parameters (i.e., internal vortex finder diameter and insertion depth) on separation performance. The research results showed that the larger the diameter of the internal vortex finder, the greater the overflow yield and the larger the cut size. The finest internal overflow product can be obtained when the internal vortex finder is 30 mm longer than the external vortex finder. The separation efficiency is highest when the internal vortex finder is 30 mm shorter than the external vortex finder.