Optimization and modeling of nanofiltration of tomato paste plant wastewater

In this Research, the effects of transmembrane pressure at three levels (10, 15, 20 bar), pH at three levels (4, 5, 6), temperature at three levels (30, 40, 50 oС) on the permeate flux and the fouling during the nanofiltration of wastewater obtained from tomato paste plant were investigated. Response surface methodology (RSM) based on the D-optimal design was employed to arrange the experiment design and to analyze the experimental data. The results demonstrated that the quadratic polynomial models are highly promising for modelling the permeate flux and fouling (R2 equal to 0.96 & 0.93, respectively). In addition, the results demonstrated that the lack-of-fit tests have been found to be insignificance in all cases, along with high values for the adequacy precision. The desirability function has been achieved as 0.89. The optimum condition has been found as following: the pressure of 20 bars, temperature of 30 oС, and pH of 5.6, respectively. There was no significant difference between experimental and predicted values in the optimum condition.