Improvement of Separation Efficiency in Multiple Hydrocyclones

• Main Authors: Sin-Yi Lyu, 呂信毅
• Other Authors: Kuo-Jen Hwang
• Format: Others
• Language: zh-TW
• Published: 2004
• Online Access: http://ndltd.ncl.edu.tw/handle/68537099639641552824

碩士 === 淡江大學 === 化學工程與材料工程學系碩士班 === 94 === Effects of operating conditions on the particle separation efficiency of multiple hydrocyclones are studied and discussed. Two 10 mm-diameter hydrocyclones installed in series are used in experiments and in computational fluid dynamics (CFD) analyses. Experimental results show that an increase in pressure drop or split ratio, whatever in the first or the second hydrocyclone, leads the partial separation efficiency to be increase and the concentration of the final overflow to be decrease. The optimum operating condition for the separation of corn starch suspension can be selected as: the split ratios are set as 3.3 and 1.57 in the first and the second hydrocyclone, respectively, and the pressure drop is set as 0.4 MPa in the first hydrocyclone. The particle concentration in the final overflow is 13% lower than that in the use of single hydrocyclone. The fluid velocity and pressure profiles in the hydrocyclone are simulated by computational fluid dynamics method. The locus of zero velocity in the equilibrium orbit theory, the air core in the center of hydrocyclone and the short-cut phenomenon near the vortex finder can also be simulated using FLUENT software. Although the tendency and the occurrence of fish-hook effect in partial separation efficiency curve agree with experimental data, simulation results are still two-fold lower than experimental data. It is necessary to improve the simulation method to obtain accurate data in the near future.