RESPONSE SURFACE MODELLING AND OPTIMIZATION OF SINGLE STAGE FLUIDIZED BED AND STUDIES ON QUALITY OF FLUIDIZATION

摘要

Experiments have been carried out extensively to study the effect of operating variables such as column diameter, static bed height and gas mass velocity on fluctuation ratio. The statistical software package, design expert have been used for regression analysis of experimental data. Analysis of variance (ANOVA) has been used to estimate the statistical parameter. A 2~3 full factorial central composite design (CCD) has employed. ANOVA shows a high coefficient of correlation value (R~2=0.9787). A satisfactory second order regression model has been developed and it has been observed that the quality of fluidization which can be expressed in terms of fluctuation ratio is a direct function of gas mass velocity and column diameter and varies inversely with static bed height. It has also been observed that the 'Pred R-Squared' of 0.8310 is in reasonable agreement with the 'Adj R-Squared' of 0.9595. Furthermore, the developed model has been optimized using quadratic programming(QP) to minimize the fluctuation ratio within the experimental range studied. The optimum conditions were found to be hs/Dc: 1.21 dp/Dc: 0.0036 and G_g/G_(mf):1.33 to achieve the minimum fluctuation ratio of 1.05538 compared to that of the experimentally observed value of 1.053.