Predictive tool for monitoring RO and NF membranes

A method for monitoring fouling of membranes of a desalination or water softening plant comprising reverse osmosis (RO) membranes, nanofiltration (NF) membranes, or a combination thereof, the method comprising:

• predicting, for one or more RO/NF skids, a time until which a cleaning in place (CIP) of the one or more RO/NF skids is indicated, wherein each of the one or more RO/NF skids comprises one or more RO/NF arrays, wherein each of the one or more RO/NF arrays comprises a plurality of RO units and each RO unit contains therein a plurality of RO membranes, a plurality of NF units and each NF unit contains therein a plurality of NF membranes, or a combination thereof, wherein the predicting comprises:
• calculating and/or monitoring one or more RO/NF parameters,
• comparing each of the one or more RO/NF parameters to a performance threshold, wherein the performance threshold indicates a time at which a cleaning in place (CIP) of the RO/NF skid based on that parameter is to be performed, and estimate a time until which each of the one or more RO/NF parameters will reach the performance threshold therefor, and
• predicting as the time until which a cleaning in place (CIP) of the one or more RO/NF skids is indicated as the lowest time estimated from among the estimated times until which each of the one or more RO/NF parameters will reach the performance threshold therefor.

A computer system operable for monitoring fouling of membranes of a desalination or water softening plant comprising ultrafiltration (UF) membranes, reverse osmosis (RO) membranes, nanofiltration (NF) membranes, or a combination thereof, the system comprising:

• a controller comprising a processor configured to:
• receive as inputs:
• for one or more UF skids comprising a plurality of UF units, each UF unit containing therein a plurality of UF membranes:
• an inlet temperature, inlet pressure, outlet pressure, flow rate, or a combination thereof;
• for one or more RO/NF skids comprising one or more RO/NF arrays, wherein each of the one or more RO/NF arrays comprises a plurality of RO units, each RO unit containing therein a plurality of RO membranes, a plurality of NF units, each NF unit containing therein a plurality of NF membranes, or a combination thereof:
• inlet temperature, feed pressure, outlet pressure, feed flow rate, permeate flow rate, total dissolved solids (TDS) in the permeate streams from, or a combination thereof for each of the one or more RO/NF arrays;
• or a combination thereof,
• utilize the inputs:
• for the one or more UF skids to calculate and/or monitor, for each of the one or more UF skids, one or more UF parameters,
• for the one or more RO/NF skids to calculate and/or monitor one or more RO/NF parameters;
• or a combination thereof;
• compare:
• each of the one or more UF parameters to a first performance threshold, wherein the first performance threshold indicates a time at which a cleaning in place (CIP) of the UF skid is to be performed, and predict an estimated time until which each of the one or more UF parameters will reach the first performance threshold;
• each of the one or more RO/NF parameters to a second performance threshold, wherein the second performance threshold indicates a time at which a cleaning in place (CIP) of the RO/NF skid is to be performed, and predict an estimated time until which each of the one or more RO/NF parameters of an RO/NF skid will reach the second performance threshold therefor;
• or a combination thereof;
• and
• predict a time until which a cleaning in place (CIP) of each of the one or more RO/NF skids, UF skids, or both is indicated as the lowest time estimated from among the estimated times until which each of the one or more RO/NF parameters or UF parameters will reach the first performance threshold or the second performance threshold, respectively.