Optimization of vacuum membrane distillation parameters for water desalination using Box-Behnken design

Water desalination via vacuum membrane distillation (VMD) requires a proper process parametric study to determine optimal performance characteristics. In this study, response surface methodology, involving Box-Behnken design matrix for most important operating parameters: feed temperature, vacuum pressure, feed flow rate, and feed concentration, have been employed. Consequently, 27 experiments were conducted to construct a quadratic model. Optimal experimental conditions for water desalination via VMD were obtained using analysis of variance, feed temperature (T=55 degrees C), vacuum pressure (P-v=10mbar), feed flow rate (Q=38.63mL/s), and feed concentration (C=100g/L). Under these conditions the measured permeate flux 17.96kg/m(2)h was found to be the highest value in this study confirming the validity of the applied optimization procedure. Regression analysis showed agreement of the experimental data with the second-order polynomial model with determination coefficient (R-2) value of 0.9880.