Method of monitoring membrane cleaning processes
Methods and systems for monitoring and/or controlling the cleaning of membrane separation systems or processes are provided. The present invention utilizes measurable amounts of inert fluorescent tracer(s) added to a membrane cleaning process stream to evaluate and/or control the removal of contaminants and/or impurities during cleaning. The methods and systems of the present invention can be utilized in a variety of different industrial applications including raw water processing and waste water processing.
1 . A cleaning system capable of cleaning a membrane separation system adapted for use in an industrial process comprising:
an inert fluorescent tracer and a cleaning solution added to the membrane separation system during cleaning;
a detection device capable of fluorometrically measuring an amount of the inert fluorescent tracer ranging from about 5 ppt to about 1000 ppm during cleaning of the membrane separation system wherein the detection device is capable of producing a signal indicative of the amount of inert tracer that is measured; and
a controller capable of processing the signal to monitor the cleaning of the membrane separation system.
2 . The cleaning system of claim 1 wherein the membrane separation system is adapted for use in an industrial process selected from the group consisting of raw water processes, waste water processes, industrial water processes, municipal water treatment, food and beverage processes, pharmaceutical processes, electronic manufacturing, utility operations, pulp and paper processes, mining and mineral processes, transportation-related processes, textile processes, plating and metal working processes, laundry and cleaning processes, leather and tanning processes, and paint processes.
3 . The cleaning system of claim 1 wherein the membrane separation system performs a membrane separation process selected from the group consisting of a cross-flow membrane separation process and a dead-end flow membrane separation process.
4 . The cleaning system of claim 3 wherein the membrane separation process is selected from the group consisting of reverse osmosis, ultrafiltration, microfiltration, nanofiltration, electrodialysis, electrodeionization, pervaporation, membrane extraction, membrane distillation, membrane stripping, membrane aeration and combinations thereof.
5 . The method of claim 1 wherein the cleaning system is capable of monitoring at least one parameter specific to cleaning the membrane separation system selected from the group consisting of a concentration of the cleaning solution, a concentration of a treatment chemical, a hold-up volume of the membrane separation system and combinations thereof.
6 . The method of claim 5 wherein the cleaning system monitors a dilution effect on the concentration of the cleaning solution during the circulation step due to the hold-up volume.
7 . The method of claim 5 wherein the cleaning system monitors the removal of the cleaning solution during the rinsing step.
8 . The method of claim 1 wherein the controller controllably adjusts cleaning of The membrane separation system based on the measurable amount of the inert fluorescent tracer.