MEMS Based Membrane Sensor System and Method of Use

• US 20140180610A1
• Filed: 12/21/2012
• Published: 06/26/2014
• Est. Priority Date: 12/21/2012
• Status: Active Grant

• Current Assignee: BL Technologies Inc. (Ashland Global Holdings, Inc.)
• Original Assignee: General Electric Company
• Inventors: Chatterjee, Aveek, Bhattacharyya, Arjun, Chandrasekaran, Shankar
• Granted Patent: US 9,709,429 B2
• Time in Patent Office: Days
• US Class Current: 702/45
• CPC Class Codes: B01D 2311/14 Pressure control
• CPC Class Codes: B01D 2311/16 Flow or flux control
• CPC Class Codes: B01D 2311/243 Electrical conductivity control
• CPC Class Codes: B01D 2313/60 Specific sensors or sensor arrangements
• CPC Class Codes: B01D 2313/64 Bar codes; Data storage means; RFID
• CPC Class Codes: B01D 2317/04 Elements in parallel
• CPC Class Codes: B01D 2319/022 Reject series
• CPC Class Codes: B01D 61/12 Controlling or regulating
• CPC Class Codes: B01D 63/106 Anti-Telescopic-Devices [ATD]
• CPC Class Codes: B01D 63/12 comprising multiple spiral-wound assemblies
• CPC Class Codes: C02F 1/008 Control or steering systems not provided for elsewhere in subclass C02F
• CPC Class Codes: C02F 1/441 by reverse osmosis
• CPC Class Codes: C02F 1/442 by nanofiltration
• CPC Class Codes: C02F 2209/008 comprising telecommunication features, e.g. modems or antennas
• CPC Class Codes: C02F 2209/02 Temperature
• CPC Class Codes: C02F 2209/03 Pressure
• CPC Class Codes: C02F 2209/05 Conductivity or salinity
• CPC Class Codes: C02F 2209/40 Liquid flow rate
• CPC Class Codes: G01F 1/8436 signal processing
• CPC Class Codes: G01F 3/00 Measuring the volume flow of fluids or fluent solid material wherein the fluid passes through the meter in successive and more or less isolated quantities, the meter being driven by the flow measuring a proportion of the volume flow G01F5/00
• CPC Class Codes: G06F 17/00 : Digital computing or data processing equipment or methods, specially adapted for specific functions information retrieval, database structures or file system structures therefor G06F16/00

Abstract

A MEMS sensor system for monitoring membrane elements in a membrane based water filtration plant having a remote telemetry unit (RTU), a SCADA, and a plurality of MEMS sensors for measuring pressure, flow rate. and conductivity. The water filtration plant has a train with a membrane vessel containing a plurality of membrane elements arranged in series creating interfaces between each membrane element. The MEMS sensors are located at the membrane element interfaces. A method of monitoring membrane elements in a membrane based water filtration plant using a plurality of MEMS sensors for measuring pressure, flow rate. and conductivity placed at the filtration plant membrane element interfaces.

Claims

1. A micro-electromechanical systems (MEMS) sensor system for a membrane based water filtration plant comprising:

a remote telemetry unit (RTU), a supervisory control and data acquisition unit (SCADA), and a plurality of MEMS sensors for measuring pressure, flow rate. and conductivity of a stream;

said water filtration plant is comprised of a train comprised of a membrane vessel containing a plurality of membrane elements;

said membrane elements receive a feed stream and produce a concentrate stream and a permeate stream;

said membrane elements are arranged in series creating interfaces between each membrane element;

said MEMS sensors measure the flow rate, pressure, and conductivity of said feed stream, concentrate stream, and permeate stream at said membrane interfaces;

said membrane vessel receives a feed stream and produces a permeate stream and a concentrate steam;

conventional pressure sensors measure the pressure of said membrane vessel permeate, concentrate, and feed streams;

conventional conductivity sensors measure the conductivity of said membrane vessel permeate, concentrate, and feed streams;

conventional flow sensors measure the flow rate of said membrane vessel permeate, concentrate, and feed streams;

conventional temperature sensor measures the temperature of said membrane vessel feed stream;

said RTU communicates with said MEMS sensors and said SCADA to provide said MEMS sensor pressure and conductivity measurements to said SCADA, said RTU communicates wirelessly with said MEMS sensors;

said conventional sensors provide measurements directly to said SCADA;

wherein said SCADA uses said MEMS sensor and said conventional sensor measurements to identify compromised membrane elements.

2. The MEMS sensor system of claim 1, wherein said system identifies compromised membrane elements by calculating a normalized permeate flow rate, normalized differential pressure, and normalized salt passage for each membrane element using said MEMS sensor and said conventional sensor measurements, and comparing said calculated normalized permeate flow rate, normalized differential pressure, and normalized salt passage for each membrane element to normalized permeate flow rate, normalized differential pressure, and normalized salt passage for each membrane element at reference conditions.

3. The MEMS sensor system of claim 1, wherein said system identifies compromised membrane vessels by calculating a normalized permeate flow rate, normalized differential pressure, and normalized salt passage for said membrane vessel using said conventional sensor measurements, and comparing said calculated normalized permeate flow rate, normalized differential pressure, and normalized salt passage for said membrane vessel to normalized permeate flow rate, normalized differential pressure, and normalized salt passage for said membrane vessel at reference conditions.

4. The MEMS sensor system of claim 3, wherein said membrane element is identified as compromised when said calculated normalized permeate flow of said membrane element is at least about 5% less than said normalized permeate flow of said membrane element at reference conditions;

wherein said membrane element is identified as compromised when said calculated normalized differential pressure of said membrane element is at least about 5% greater than said normalized pressure differential of said membrane element at reference conditions;

wherein said membrane element is identified as compromised when said calculated normalized salt passage of said membrane element is at least about 5% greater than said normalized salt passage of said membrane element at reference conditions;

wherein said membrane vessel is identified as compromised when said calculated normalized permeate flow of said membrane vessel is at least about 5% less than said normalized permeate flow of said membrane vessel at reference conditions;

wherein said membrane vessel is identified as compromised when said calculated normalized differential pressure of said membrane vessel is at least about 5% greater than said normalized pressure differential of said membrane vessel at reference conditions;

wherein said membrane vessel is identified as compromised when said calculated normalized salt passage of said membrane vessel is at least about 5% greater than said normalized salt passage of said membrane vessel at reference conditions.

5. The MEMS sensor system of claim 1, wherein each of said MEMS sensors is comprised of at least one of a flow sensor, pressure sensor, or a conductivity sensor.

6. The MEMS sensor system of claim 1, wherein each of said MEMS sensors is comprised of a removable smart sensor structure (RSSS) and a control/data transceiver chip (CDTC);

said RSSS is comprised of a smart part and at least one of a pressure sensor or a conductivity sensor;

wherein said smart part is comprised of a coil, voltage regulator, inductive transceiver, non-volatile memory, microprocessor, and conversion circuitry;

wherein said CDTC is comprised of a coil, inductive transceiver, and RF transceiver.

7. The MEMS sensors of claim 6, wherein each of said MEMS sensor is powered by a battery in said CDTC, or wirelessly by said RTU.

8. The MEMS sensor of claim 1, wherein each of said MEMS sensors employs one or both of smart power or smart monitoring.

9. The MEMS sensor of claim 1, wherein each of said MEMS sensors contain housekeeping information.

10. The MEMS sensor of claim 1, wherein each of said MEMS sensors are mounted to an anti-telescoping device (ATD) of said membrane elements, wherein said MEMS sensors are mounted in a press-fit slot or a fastener slot of said ATD.

11. A method of operating a MEMS sensor system for a membrane based water filtration plant comprising:

providing a MEMS sensor system and a membrane train, said membrane train is comprised of a membrane vessel containing a plurality of membrane elements, said membrane elements are arranged in series to create membrane interfaces between each membrane element;

said MEMS sensor system is comprised of a plurality of MEMS sensors and a SCADA;

providing said membrane vessel with a feed stream, wherein said membrane vessel produces a concentrate stream and a permeate stream;

said membrane vessel is further comprised of a conventional flow sensor, a conventional pressure sensor and a conventional conductivity sensor in each of said feed stream entering said membrane vessel, and concentrate stream and permeate stream exiting said membrane vessel;

wherein said membrane vessel is further comprised of a conventional temperature sensor in said feed stream entering said membrane vessel;

providing each of said membrane elements with a feed stream, wherein each of said membrane elements produce a concentrate stream and a permeate stream;

said MEMS sensors are placed in said feed stream, concentrate stream, and permeate stream at said membrane interfaces;

obtaining normalized permeate flow rate, normalized differential pressure, and normalized salt passage for each of said membrane elements and membrane vessel at reference conditions;

prompting said MEMS sensors and said conventional sensors to acquire flow rate, pressure, and conductivity measurements;

prompting said conventional temperature sensor to acquire the temperature of said feed stream at time “

t”

;

providing said flow rate, pressure, and conductivity measurements of said feed, permeate, and concentrate streams at said membrane interfaces and said membrane vessel at time “

t”

to said SCADA;

providing said temperature of said feed stream of said membrane vessel at time “

t”

to said SCADA;

calculating said normalized permeate flow rate, normalized differential pressure, and normalized salt passage for each membrane element and membrane vessel at time “

t”

using said temperature, flow rate, pressure and conductivity measurements obtained at time “

t”

; and

comparing said calculated normalized permeate flow rate, normalized differential pressure, and normalized salt passage of each membrane element and membrane vessel at time “

t” and

normalized permeate flow rate, normalized differential pressure, and normalized salt passage of each membrane element and membrane vessel at reference conditions to identify compromised membrane elements and membrane vessels.

12. The method of claim 11 further comprising retrieving housekeeping information from said MEMS sensors and updating said housekeeping information.

13. The method of claim 11 further comprising reporting to a user said normalized permeate flow rate, normalized differential pressure, and normalized salt passage of each membrane element and membrane vessel at time “

t”

, said normalized permeate flow rate, normalized differential pressure, and normalized salt passage of each membrane element and membrane vessel at reference conditions, and the location of said compromised membrane elements and membrane vessels.

14. The method of claim 12, wherein said membrane element is identified as compromised when said calculated normalized permeate flow of said membrane element is at least about 5% less than said normalized permeate flow of said membrane element at reference conditions;

wherein said membrane element is identified as compromised when said calculated normalized differential pressure of said membrane element is at least about 5% greater than said normalized pressure differential of said membrane element at reference conditions;

wherein said membrane element is identified as compromised when said calculated normalized salt passage of said membrane element is at least about 5% greater than said normalized salt passage of said membrane element at reference conditions;

wherein said membrane vessel is identified as compromised when said calculated normalized permeate flow of said membrane vessel is at least about 5% less than said normalized permeate flow of said membrane vessel at reference conditions;

wherein said membrane vessel is identified as compromised when said calculated normalized differential pressure of said membrane vessel is at least about 5% greater than said normalized pressure differential of said membrane vessel at reference conditions;

wherein said membrane vessel is identified as compromised when said calculated normalized salt passage of said membrane vessel is at least about 5% greater than said normalized salt passage of said membrane vessel at reference conditions.

15. The method of claim 11, wherein said conductivity measurements are comprised of measurements of the concentration of individual analytes of interest and the total concentration of all analytes of interest.

16. The method of claim 11, wherein each of said MEMS sensors is comprised of at least one of a flow sensor, pressure sensor, or a conductivity sensor.

17. The method of claim 11, wherein said MEMS sensor is comprised of a removable smart sensor structure (RSSS) and a control/data transceiver chip (CDTC);

said RSSS is comprised of a smart part and at least one of a pressure sensor or a conductivity sensor;

wherein said smart part is comprised of a coil, voltage regulator, inductive transceiver, non-volatile memory, microprocessor, and conversion circuitry;

wherein said CDTC is comprised of a coil, inductive transceiver, and RF transceiver.

18. The method of claim 11, wherein said MEMS sensor is powered by a battery in said CDTC.

19. The method of claim 11, wherein a remote telemetry unit (RTU) communicates with said MEMS sensors and said SCADA to provide said MEMS sensor pressure and conductivity measurements to said SCADA, wherein said MEMS sensors are powered wirelessly by said RTU.

20. The method of claim 11, wherein said MEMS sensors employ one or both of smart power or smart monitoring.