Conventionally membrane research implements cross-flow filtration scheme to reduce membrane fouling. The control and optimization of such membrane apparatus have been tedious due to the simultaneous change of various parameters such as applied pressure, flow rate of feed, permeate and concentrate, and feedwater recovery during the course of membrane filtration. Since the accurate control of the operating parameters is critical for data quality, it becomes imperative to have system being controlled automatically. Automatic data acquisition and control ensures accurate data collection and that the data generated are more reliable and with minimum possible errors.; In this study, a fully automated cross flow nanofiltration apparatus has been successfully developed and characterized. Using LabVIEW as a programming language, it has been possible to completely automate the filtration system. System is designed to control two parameters and acquire two additional data simultaneously. Numbers of experiments have been carried out to optimize control parameters such as acquisition rate, number of samples per second, various control parameters for two controllers etc.; A detailed and user-friendly front panel (user interface) has been developed to make system easy to use. This panel shows two plots showing trend of all the parameters. It also has auto-manual selection switch, knob for valve opening selection in manual mode, set point selectors and indictors for all present value. It does give smooth mode transfer from manual to auto.; It is observed that best rate for the data acquisition is 100 samples/sec with 100 samples averaged every second. The optimum control parameters, obtained by Ziegler-Nickols technique, for flow controller are: Kc = 0.26, Ti = 0.0335 mins, Td = 0.00837 mins. These parameter for the pressure controller are found to be: Kc = 0.0195, Ti = 0.05 mins, Td = 0.0125 mins.
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