DEVICES AND METHODS FOR LANDFILL GAS WELL MONITORING AND CONTROL

• US 20140182846A1
• Filed: 03/11/2013
• Published: 07/03/2014
• Est. Priority Date: 01/02/2013
• Status: Active Grant

• Current Assignee: Q.E.D. Environmental Systems, Inc. (Graco Incorporated)
• Original Assignee: Q.E.D. Environmental Systems, Inc. (Graco Incorporated)
• Inventors: Fischer, David A., Mioduszewski, David
• Granted Patent: US 9,062,536 B2
• Time in Patent Office: Days
• US Class Current: 166/250.15
• CPC Class Codes: B09B 1/006 Shafts or wells in waste dumps
• CPC Class Codes: B09B 3/80 involving an extraction step
• CPC Class Codes: E21B 34/025 Chokes or valves in wellheads and sub-sea wellheads for variably regulating fluid flow
• CPC Class Codes: E21B 43/12 Methods or apparatus for controlling the flow of the obtained fluid to or in wells E21B43/25 takes precedence; valve arrangements E21B34/00
• CPC Class Codes: E21B 44/00 Automatic control systems specially adapted for drilling operations, i.e. self-operating systems which function to carry out or modify a drilling operation without intervention of a human operator, e.g. computer-controlled drilling systems; Systems specially adapted for monitoring a plurality of drilling variables or conditions
• CPC Class Codes: E21B 47/00 Survey of boreholes or wells monitoring pressure or flow of drilling fluid E21B21/08
• CPC Class Codes: H04B 1/3833 Hand-held transceivers
• CPC Class Codes: H04W 4/80 Services using short range communication, e.g. near-field communication [NFC], radio-frequency identification [RFID] or low energy communication

Abstract

A landfill well control system includes a mobile hand-held device provided with a software monitoring application including a table having data related to determination of a desired methane gas output flow rate. A landfill gas (LFG) wellhead gas control valve includes: an electronically controlled, powered flow control device actuator; a flow measurement element producing differential pressures proportional to a gas flow rate; a pressure sensor/transducer; and a microprocessor having control logic capability and the ability to communicate via a local wireless signal to the mobile hand-held device. The powered flow control device actuator using data from the table of the mobile hand-held device or remotely stored data provides automatic valve positioning.

Claims

1. A landfill well control system for use in connection with landfill well, wherein landfill gas is produced within a wellbore of the landfill well, the system comprising:

a hand holdable device having a processor with a software monitoring application running thereon, the software monitoring application including a table having stored data used by the processor in computing a desired landfill gas output flow rate; and

a landfill gas (LFG) wellhead gas control valve operably associated with a wellhead assembly, the LFG wellhead gas control valve including a flow control device operating to control a landfill gas flow rate of the landfill gas being withdrawn through the LFG wellhead gas control valve from the landfill well bore, the LFG wellhead gas control valve.

2. The landfill well control system of claim 1, wherein the hand holdable device comprises a wireless communications device, and wherein the flow control device of the LFG wellhead gas control valve comprises an electronically controlled flow control device;

and

further including a flow measurement element provided at the LFG wellhead gas control valve producing differential pressures proportional to the landfill gas flow rate, the differential pressures converted to signals communicated to the wireless communications device.

3. The landfill well control system of claim 1, further including a pressure sensor/transducer provided at the LFG wellhead gas control valve.

4. The landfill well control system of claim 1, further including a microprocessor provided at the LFG wellhead gas control valve having control logic capability and a wireless transmitter to communicate via a local wireless signal to the hand holdable device.

5. The landfill well control system of claim 1, wherein the hand-holdable device comprises a wireless device configured to communicate wirelessly with the LFG wellhead gas control valve.

7. The landfill well control system of claim 1, further including:

a pressure drop measurement device configured to be removably coupled to a pressure gradient producing orifice assembly associated with the wellhead assembly.

8. The landfill well control system of claim 1, further including indexing marks created on the LFG wellhead gas control valve identifying a plurality of corresponding valve position element positions for enabling a user to set the LFG wellhead gas control valve to a desired position that corresponds to a desired gas flow rate and for a set of well operating parameters including temperature, barometric pressure and humidity.

9. The landfill well control system of claim 1, wherein the hand holdable device comprises a device having wireless communications capability, and further including a mass flow rate device to electronically send a wireless mass flow rate measurement signal of the landfill gas to the hand holdable device.

6. (canceled)

10. A landfill well control system, comprising:

a mobile hand-held device having a wireless communications subsystem and a processor, the processor running a software monitoring application including a table, the table having data related to determination of a desired landfill gas output flow rate of a landfill gas; and

a landfill gas (LFG) wellhead gas control valve including;

an electronically controlled, powered flow control device actuator;

a flow measurement element producing differential pressures proportional to a landfill gas flow rate;

a pressure sensor/transducer; and

a microprocessor having control logic capability for controlling the electronically actuated, powered flow control device actuator, and further being configured to communicate via a short range, wireless signal with the wireless communications subsystem of the mobile hand-held device.

11. The landfill well control system of claim 10, wherein the flow measurement element further includes an internal pressure transducer, a micro-controller and a wireless communications device including a suite of high level communication protocols using digital radios, the flow measurement element being connected to the LFG well head.

12. The landfill well control system of claim 10, wherein the mobile hand-held device includes a program providing for input of a pressure drop device specification including an orifice size of an orifice assembly.

13. The landfill well control system of claim 10, wherein the mobile hand-held device includes a flow control device index position indicated by a set of indexing marks located on the LFG wellhead gas control valve, the index position included in determining the landfill gas flow rate.

14. The landfill well control system of claim 10, wherein the mobile hand-held device includes LFG data including LFG well head vacuum and pressure, LFG gas quality data, LFG gas temperature, site and ambient data readings such as barometric pressure, air temperature, and/or a geospatial location of an LFG well head.

15. A landfill well control system, comprising:

a wireless device provided with a processor running a software monitoring application including a table having data related to determination of a desired landfill gas output flow rate;

a landfill gas (LFG) wellhead gas control valve including an electronically controlled, powered flow control device actuator operating to control a landfill gas flow rate of a landfill gas, the LFG wellhead gas control valve in wireless communication with the wireless device; and

a data storage device in communication with the mobile hand-held device, the data storage device retaining historical data of the landfill gas flow rate accessible in the data storage device at the same time new data is acquired.

16. The landfill well control system of claim 15, further including a mobile hand-held device used to communicate control target settings and readings via local wireless signals to the LFG wellhead gas control valve.

17. The landfill well control system of claim 16, further including a powered flow control device actuator connected to and operating to change a position of the LFG wellhead gas control valve, the powered flow control device actuator having a wireless communications device to communicate and change the valve position using the mobile hand-held device.

18. The landfill well control system of claim 15, further including a keypad and a digital display located at a well head having the LFG wellhead gas control valve, the keypad used to enter desired control target settings of the LFG wellhead gas control valve.

19. The landfill well control system of claim 15, further including a self-regulating gas flow control valve and an oxygen sensor monitored by an operator to maintain a landfill well oxygen level below a desired set-point.

20. A method for controlling an output flow rate of a landfill gas, comprising:

storing historical data of landfill gas output flow rates;

using a processor running a software application to process the historical data to determine a recommended flow control valve position adjustment in real time, to thus adjust the output flow rate of the landfill gas in real time; and

wirelessly transmitting the recommended flow control valve position to a landfill gas wellhead gas control valve.

21. The method of claim 20, further comprising repeating the storing step for multiple landfill gas well heads of a common landfill site, including historical readings from individual ones of the multiple landfill gas well heads and multiple ones of the recommended flow control valve position.

22. The method of claim 20, further comprising:

1) periodically, including from between 1-12 times daily, “

hunt”

via directing stepwise openings and closings of the gas flow control valve;

2) taking new measurements of a landfill gas flow rate; and

3) computing a ratio of an additional landfill gas flow rate gained divided by a change in a vacuum level applied to the well head assembly.