Performance of ultrafiltration membrane technology in treatment of soy whey wastewater

The capability and process characteristics of ultrafiltration membrane technology treating soy whey wastewater were investigated by using regenerated fiber membrane (RC) and PES membrane (PES) with molecular weight cutoff (MWCO) of 5000, 10000 and 30000, respectively. The permeation flux, membrane attenuation coefficient, rejection rate of protein, carbohydrate permeation rate of all kinds of membranes were studied through the test. The results showed that by comprehensively considering flux, decline factor, protein rejection coefficient and carbohydrates permeation rate, RC-10000 was the suitable membrane for separating soybean whey. The experimental results demonstrated that the optimal operation pressure of ultrafiltration membrane was 30 kPa, the optimal pH was 9, concentration ratio was 3:1, and temperature was 20°C. The permeation flux was 31.2 L·m^-2·h^-1 and rejection rate of protein and protein content were 78.46% and 51.37%, respectively. In order to optimize operation parameters and predict the permeation flux of the ultrafiltration membrane for soy whey wastewater treatment, a simulation model of operation parameters was established based on curve fitting and back-propagation neural network (BPNN). Simulated results by the simulation model analysis were basically consistent with experimental values. This indicated that the simulation model on the basis of curve fitting and BPNN was practical.