An improved relationship to predict expanded bed height in particulate fluidization

Abstract

To predict the bed expansion in liquid-solid fluidization, which is typically particulate in nature, the earlier equation, proposed by the author, is a polynomial one of the following form: 1 R = 1 − 1.762U + 0.95U 2 . The proposed equation, unfortunately, suffers a few drawbacks, the most serious of which is that it does not satisfy one of the essential conditions of bed expansion, i.e. at U = 1 (or u f = u t), 1 R = 0 . To eradicate such defect, an alternative method is suggested to predict directly the expanded bed height of poly-dispersed systems as: L e = 1 Σ alli ( x i L ei ) . The equation is found to cause an overall improvement of 16.7% from the previous one, based on 646 bed expansion data of 49 multicomponent fluidized bed systems.