Document Type : Regular Article
Author
Faculty of Petroleum and Chemical Engineering, Razi University, Kermanshah, Iran
Abstract
A new approach is proposed to evaluate various designs for gas-solid cyclone separators. This approach uses single-phase flow simulation results to find a quantitative measure of flow symmetry in a given cyclone. Flow symmetry is computed by averaging imbalances of non-axial velocities throughout the cyclone. Using this approach, two standard design methods are evaluated and the cyclone with a more symmetric flow pattern is chosen as a starting point for further design improvements by reducing the diameter of its vortex finder. Two-phase computational fluid dynamics (CFD) simulations compute 90.2 % collection efficiency for the improved design. CFD simulations reveal using a cascade of four cyclones results in an overall 99.98 % collection efficiency. Once installed in the actual industrial setting, the cyclone cascade achieves a 98.56 % collection efficiency and a particle size distribution which is in good agreement with CFD computed results.
Keywords
Main Subjects
References
- Khare, N. P., Seavey, K. C. and Liu, Y. A., “Steady state and dynamic modeling of commercial slurry high density polyethylene (HDPE) processes”, Industrial and Engineering Chemistry Research, 41, 5601 (2002).
- Cui, J., Chen, X., Gong, X. and Yu, G., “Numerical study of gas-solid flow in a radial-inlet structure cyclone separator”, Industrial and Engineering Chemistry Research, 49, 5450 (2010).
- Zhao, B., Su, Y. and Zhang, J., “Simulation of gas flow pattern and separation efficiency in cyclone with conventional single and spiral double inlet configuration”, Chemical Engineering Research and Design, 84 (A12), 1158 (2006).
- Elsayed, K. and Lacor, C., “The effect of cyclone inlet dimensions on the flow pattern and performance”, Applied Mathematical Modelling, 35, 1952 (2011).
- Lee, J. W., Yang, H. J. and Lee, D. Y., “Effect of cylinder shape of a long coned cyclone on the stable flow-field establishment”, Powder Technology, 165, 30 (2006).
- Su, Y., Zhao, B. and Zheng, A., “Simulation of tubulent flow in square cyclone separator with different gas exhaust”, Industrial and Engineering Chemistry Research, 50, 12162 (2011).
- Zhang, T., Liu, C., Guo, K., Liu, H. and Wang, Z., “Analysis of flow field in optimal cyclone separators with hexagonal structure using mathematical models and computational fluid dynamics simulation”, Industrial and Engineering Chemistry Research, 55, 351 (2015).
- Lim, K. S., Kim, H. S. and Lee, K. W., “Characteristics of the collection efficiency for a cyclone with different vortex finder shapes”, Journal of Aerosol Science, 35, 743 (2004).
- Shepherd, C. B. and Lapple, C. E., “Flow pattern and pressure drop in cyclone dust collectors”, Journal of Industrial and Engineering Chemistry, 31 (8), 972 (1939).
- Shepherd, C. B. and Lapple, C. E., “Flow pattern and pressure drop in cyclone dust collectors”, Journal of Industrial and Engineering Chemistry, 32, 1246 (1940).
- Stairmand, C. J., “The design and performance of cyclone separators”, Transactions of the Institution of Chemical Engineers, 29, 356 (1951).
- Safikhani, H., Akhavan-Behabadi, M. A, Shams, M. and Rahimyan, M. H., “Numerical simulation of flow field in three types of standard cyclone separators”, Advanced Powder Technology, 21, 435 (2010).
- Andersson, B., Andersson, R., Hakansson, L., Mortensen, M., Sudiyo, R. and van Wachem, B., Computational fluid dynamics for engineers, Cambridge University Press, (2012).
- Slack, M. D., Prasad, R. O., Bakker, A. and Boysan, F., “Advances in cyclone modelling using unstructured grids”, Chemical Engineering Research and Design, 78 (8), 1098 (2000).
- Chuaha, T. G., Gimbun, J. and Choong, T. S. Y., “A CFD study of the effect of cone dimensions on sampling aero cyclones performance and hydrody namics”, Powder Technology, 162 (2), 126 (2006).
- Elsayed, K. and Lacor, C., “Optimization of the cyclone separator geometry for minimum pressure drop using mathematical models and cfd simulations”, Chemical Engineering Science, 65, 6048 (2010).
- Raoufi, A., Shams, M., Farzaneh, M. and Ebrahimi, R., “Numerical simulation and optimization of fluid flow in cyclone vortex finder”, Chemical Engineering and Processing, 47, 128 (2008).