WO2021026300A1

WO2021026300A1 - System and method for monitoring and controlling of venting of a fluid discharge line in a well system

Info

Publication number: WO2021026300A1
Application number: PCT/US2020/045119
Authority: WO
Inventors: John F. Schaupp
Original assignee: Q.E.D. Environmental Systems, Inc.
Priority date: 2019-08-06
Filing date: 2020-08-06
Publication date: 2021-02-11

Abstract

A system is disclosed for monitoring for the presence of air in a force main line of a well system, wherein the force main line is collecting liquid from at least one fluid pump disposed in a wellbore, and enabling venting of the air from the force main line. The system may have a controller, a pneumatic pump, a force main line in fluid communication with a discharge line of the fluid pump, a valve assembly and a primary vent valve. The valve assembly may be in fluid communication with the force main line and has an internal valve element movable in response to the presence of air or fluid flowing through the valve assembly. Signals from the valve assembly inform the controller whether only air or only fluid is flowing through the valve assembly, and the primary vent valve is controlled to allow venting when it is detected that only air is flowing through the valve assembly.

Description

SYSTEM AND METHOD FOR MONITORING AND CONTROLLING OF VENTING OF A FLUID DISCHARGE LINE IN A WELL SYSTEM

CROSS-REFERENCE TO RELATED APPLICATIONS [0001] This PCT International Application claims the benefit of U.S. Provisional Application No. 62/883,368, filed on August 6, 2019. The entire disclosure of the above application is incorporated herein by reference.

FIELD

[0002] The present disclosure relates to well pumps and systems for controlling well pumps, and more particularly to a system and method for use with a pump disposed in a wellbore, for monitoring a force main line of the system for the presence of air in the liquid fluid line, and controlling venting of the force main line to remove air from the line.

BACKGROUND

[0003] The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.

[0004] In applications such as landfills, often a number of well bores are located, often on different sides of a hill of the landfill. A fluid pump is disposed in each well bore. The fluid pumps are typically float controlled pneumatic pumps that rely on a compressed air source to periodically apply compressed air into a casing of each pump when the pump’s float indicates that the pump is full of fluid (typically water or some combination or water and leachate). When the float moves to an upper limit position, this controls an air supply integrated into the pump to open and admit the compressed air. The compressed air forces the fluid which has collected within each pump casing up through a discharge line connected to an upper end of the pump casing. The fluid discharged from the discharge line is directed into a force main line disposed at, slightly above, ground level. More typically, the force main line is located to direct fluid to the waste water treatment facility. Thus, one force main often has a plurality (e.g., 2, 3 or more) pumps that feed it with discharged fluid collected from the independent pumps on the hill. [0005] A problem that can develop is if one of the pumps has its air supply valve stick in the open position. This was cause the fluid in the pump to be ejected, but then cause compressed air to be blown through the full length of the fluid discharge line extending up the well bore, and into the force main line. This condition will continue as long as the air supply valve is stuck in the open position. This will pressurize the force main line up to the maximum PSI rating of the compressor that feeds all of the pumps on the hill. When this happens, as other ones of the pumps that are still operating satisfactorily begin to execute a fluid discharge cycle, they will not be able to overcome the pressure “seen” at the force main line. Put differently, the pressure head existing at the input of the force main line will prevent fluid from other pumps to be discharged into the force main line. Thus, the sticking air supply valve at one pump can operate to shut down the pumping operation of all the other pumps that have their fluid discharge lines teed into the input end of the force main line.

[0006] As one can imagine, the condition described above can require significant man hours to remediate. Typically at least one technician has to go out onto the hill and first determine which of several pumps has had its air supply valve become stuck in the open positon. This may involve checking one, two or more pumps before finding the one causing the problem. And then the problem pump has to be removed from the well bore, disassembled, cleaned and reinstalled. The entire process can take hours or more to resolve. The problem with sticking air valves is often one that can arise with significant frequency, which can give rise to repeated shut downs of all the pumps on a hill when one of them has an air supply valve that sticks in the open position.

[0007] Accordingly, a system and method which can automatically monitor for the presence of air in the force main line, and take corrective action to alleviate the problem condition to permit the other pumps to continue operating in normal fashion, would be extremely helpful to maintaining operation of the remaining properly- operating wells.

SUMMARY

[0008] This section provides a general summary of the disclosure, and is not a comprehensive disclosure of its full scope or all of its features. [0009] In one aspect the present disclosure relates to a system for monitoring for air in a force main line of a well system, wherein the force main line is collecting liquid from at least one fluid pump disposed in wellbore at a site, and enabling venting of the air from the force main line. The system may comprise a controller, a pneumatic fluid pump, a force main line in fluid communication with a discharge line of the pneumatic fluid pump, a valve assembly, and a primary vent valve. The valve assembly is in fluid communication with the force main line and includes an internal valve element movable between first and second positions in response to the presence of air or fluid flowing through the valve assembly. The valve assembly is further configured to send signals to the controller indicative of whether the valve element is in the first or second position. The primary vent valve is in communication with the valve assembly. The primary vent valve is periodically opened, and signals from the valve assembly are used by the controller to determine if air or liquid is flowing through the valve assembly, and to further control the primary vent valve in accordance with the signals provided by the first and second sensing components to enable venting of air from the force main line.

[0010] In another aspect the present disclosure relates to a system for monitoring for air in a force main line of a well system, wherein the force main line is collecting liquid from at least one fluid pump disposed in wellbore at a site where the system is employed, and enabling venting of the air from the force main line. The system may comprise a controller, a pneumatic fluid pump, a force main line in fluid communication with a discharge line of the pneumatic fluid pump, and a poppet valve assembly in fluid communication with the force main line. The poppet valve assembly may include an internal poppet valve element movable elevationally between first and second elevationally spaced apart positions in response to the presence of air or liquid flowing through the valve assembly. The poppet valve assembly may further include first and second sensing elements for sensing a position of the poppet valve element, and sending signals to the controller indicative of whether the valve element is in the first or second position. A primary vent valve is also included which in communication with the poppet valve assembly. The primary vent valve is periodically opened, and signals from the poppet valve assembly are used by the controller to determine if air or liquid is flowing through the poppet valve assembly, and to further control the primary vent valve in accordance with the signals provided by the first and second sensing components to enable air within the force main line to be vented therefrom.

[0011] In still another aspect the present disclosure relates to a method for monitoring for air in a force main line of a well system, wherein the force main line is collecting liquid from at least one fluid pump disposed in wellbore at a site, and enabling venting of the air from the force main line. The method may comprise using a valve system to receive a portion of a flow of at least one of air and liquid from the force main line. The method may further include using a primary vent valve in communication with the valve system to vent the valve system. The method may further include, while the primary vent valve is venting the valve system, sensing a position of a movable valve element within the valve system to determine if liquid or air is flowing through the valve system, and when only fluid is detected as flowing through the valve system, closing the valve system.

[0012] In still another aspect the present disclosure relates to a system for monitoring for air in a force main line of a well system, wherein the force main line is collecting liquid from at least one fluid pump disposed in wellbore at a site, and enabling venting of the air from the force main line. The system may comprise a pneumatic fluid pump, a force main line in fluid communication with a discharge line of the pneumatic fluid pump, a pressure transducer in fluid communication with the force main line, and a primary vent valve in communication with the force main line. The primary vent valve is opened when a signal from the pressure transducer indicates that a predetermined pressure within the force main line has been at least one of reached or exceeded, to enable venting of the force main line for a time sufficient to remove air from the force main line, before returning the primary vent valve to a closed position.

[0013] Further areas of applicability will become apparent from the description provided herein. It should be understood that the description and specific examples are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS [0014] The drawings described herein are for illustrative purposes only of selected embodiments and not all possible implementations, and are not intended to limit the scope of the present disclosure.

[0015] Corresponding reference numerals indicate corresponding parts throughout the several views of the drawings, wherein:

[0016] Figure 1 is a high level schematic block diagram of one embodiment of a system for automatically monitoring a fluid discharge line for the presence of air pockets, and venting the air discharge line to remove the air pockets; and

[0017] Figure 2 is a high level flowchart setting forth operations that may be performed by the system shown in Figure 1 .

DETAILED DESCRIPTION

[0018] Example embodiments will now be described more fully with reference to the accompanying drawings.

[0019] Referring to Figure 1 there is shown a system 10 in accordance with one embodiment of the present disclosure for automatically monitoring for the presence of air pockets in a fluid discharge line, and venting the fluid discharge line. The system 10 in this example may include a conventional pneumatic pump 12 having an internal float and air supply valve (not shown) which is positioned in a well bore 14. Typically the well bore 14 will be located on a hill side, for example at a landfill, but it need not be. More typically, a plurality of such pumps 12 will located on a hill 15 at a landfill, and each will be controlled independently in accordance with its own float system. For this example, the well bore 14 is shown extending into a side of the hill 15. Water and leachate enter the well bore through perforations (not shown) in the well bore 14. When the fluid level within a casing 12a of the pump rises to a predetermined “Full” level, the float mechanism within the pump actuates the internal air supply valve to open, which admits compressed air from an air compressor 16 into the pump casing 12a, and the water (or water/leachate mixture) is ejected through a discharge line 18 into a force main line 20. The force main line 20 is typically in communication with other pumps mounted on the hill side 16 as well, and thus in many implementations will be receiving the fluids pumped from two or more fluid pumps mounted on the hill side. All of the fluids pumped into the force main line 20 may be channeled to a main collection tank (not shown) associated with a waste water treatment facility. For the purpose of the following discussion the term “fluid” will mean a liquid comprising either just water, or mixture of water and leachate, or a mixture of water and other compounds.

[0020] The system 10 further includes a controller 22 having an internal valve, which in one embodiment may be a solenoid valve 24. The controller 22 may be an electronic controller, for example a microprocessor based controller with its own non-volatile memory which can be programmed. Optionally, the solenoid valve 24 could be a fully independent valve in electrical communication with the controller 22. Optionally, a wireless communications radio 25 may form a portion of the controller 22 or may be included as a fully independent subsystem in communication with the controller 22. The wireless communications radio 25 may be, for example and without limitation, a BLUETOOTH® protocol radio, a LORA® protocol radio, a ZIGBEE® protocol radio, etc. Optionally, a wired connection may be used in place of a wireless communications protocol radio to enable the controller 22 to communication over a wired connection with a central electronic monitoring system. Optionally, an Internet connection, or possibly even a cellular connection, could be made to the electronic controller 22 to enable it to communicate information (e.g., the status of the well) to other, remote subsystems. Optionally, controller 22 may communicate over a local area network (wired or wireless), which is in turn in communication with a remote monitoring subsystem.

[0021] The system 10 further includes a poppet valve assembly 26 which is in fluid communication with the force main line 20 via a Tee connection 28. The poppet valve assembly 26 is a well-known poppet valve assembly having an internal poppet valve element 26a that moves between a “Home” position, shown in Figure 1 , and a second or raised position, shown in dashed lines in Figure 1. The poppet valve element 26a carries a magnet 26b fixedly thereon. At least one magnet sensing component, but more preferably a pair of magnetic sensing components 26c and 26d, are located adjacent the poppet valve element 26a. Sensing component 26c senses the presence of the magnet 26b in the Home position and the other sensing component 26d senses the presence of the magnet 26b in the fully raised position. When only air is flowing through the poppet valve assembly 26, the magnet 26b will typically be at the Home position or raised just slightly off of the Home position to an intermediate position, but not sufficiently high to be in its “second” position, and will this condition will be sensed by the magnet 26b. When only fluid is flowing through the poppet valve assembly 26, this will force the poppet valve element 26a to the fully raised position, which will be sensed by the sensing component 26d. Thus, the combination of signals (i.e., either a logic “1 ” or “0” signal) from the sensing components 26c and 26d can detect three distinct locations of the magnet 26b: 1 ) at the Home (first) position; 2) at an intermediate position between the Home and fully raised positions; and 3) at the fully raised (second) position. In one embodiment the sensing components 26c and 26d may be conventional Hall effect sensors (“HESs”) or reed switches. Alternatively, conventional ratiometric sensors may be used.

[0022] The system 10 further includes a primary vent valve 30 in communication with an outlet of the poppet valve assembly 26, and also with the solenoid valve 24. The primary vent valve 30 in this example is a pneumatic valve that can be actuated by a compressed air signal from the solenoid valve 24 when the solenoid valve is controlled by the controller 22 to direct the compressed air signal via control line 32 to the primary vent valve 30. Optionally, the primary vent valve 30 could be formed by an electrically actuated vent valve. In that implementation, control line 32 would be an electrical conductor 32’ which applies the needed electrical control signal from the controller 22 to the primary vent valve 30. In either case, an outlet 30a of the primary vent valve 30 is coupled to a supplemental fluid discharge conduit 34 which is positioned with its distal end above a supplemental fluid tank 36.

[0023] In a first condition the primary vent valve 30 is closed. No fluid can flow through the poppet valve assembly 26. In a second condition the poppet valve assembly 26 is open, which allows air and/or fluid to flow from the force main line 20 through the poppet valve assembly 26, through the primary vent valve 30, and through the supplemental fluid discharge conduit 34. Fluid flowing through the supplemental fluid discharge conduit 34 in the second condition will be collected in the supplemental fluid tank 36.

[0024] In operation, when the pump 12 and its internal air supply valve are operating properly, the fluid being discharged from the pump 12 is pumped into the force main line 20 and eventually to the main collection tank. Thus, there will be no air pockets in the force main line 20, and the poppet valve assembly 26 will experience the full fluid pressure “head” created within the force main line 20. To ensure that the condition of an internal air supply valve of the pump 12 being stuck open is sensed, the controller 22 periodically may open the primary vent valve 30. This periodic operation may be carried out, for example, every 30 minutes, or at any other time interval that one desires. This time interval is programmed into the controller 22, so once programmed into the controller, no further action is required by the system technician or monitoring personnel. If an external timer is used along with an electrical primary vent valve 30, then the external timer may be programmed to open every 30 minutes, or at any other designated time interval. If such an external timer is used, then the controller 22 may be provided with a signal line (not shown) to reset the external electrical timer. Also a programmable logic controller (“PLC”) can be used to turn the electrical primary vent valve on or off with its internal timer.

[0025] Still further, the primary vent valve 30 can be driven by a pressure switch. The pressure switch can be either local to the system 10, or remotely located, and may be used to open the force main primary vent valve 30 either by a timed event, by poppet 26a movement, and/or both combined. For example, if the pressure rises above, for example, ten psi, in the force main line 20, the system 10 would be triggered. Thus, this operation involves watching the poppet valve element 26a to confirm the presence of air in the force main line 20. If the force main line 20 is plugged (i.e., filled with liquid), then the pressure will not decrease.

[0026] When the controller 22 initially opens the primary vent valve 30, if no air is present, then the fluid pressure “seen” by the poppet valve assembly 26 will essentially be that fluid pressure or “head” that is present in the force main line 20. This fluid pressure will be maintaining the poppet valve element 26a in its fully raised (second) position. This will be immediately sensed by the controller 22 via the signal from the sensing component 26d, which senses the presence of the magnet 26b in the fully raised position. The controller 22 may then control the solenoid valve 24 to close the primary vent valve 30. During the time that the primary vent valve 30 is open, a small amount of fluid flows into the supplemental fluid tank 36.

[0027] If the controller 22 signals the solenoid valve 24 to open the primary vent valve 30, and then receives no signal (i.e., “0” level signal) from both of the sensing components 26c and 26d, or possibly a signal from only the sensing component 26d, then the controller 22 will determine that air is flowing through the poppet valve assembly 26. The controller 22 will maintain the primary vent valve 30 in the open condition as long as no signal is received from the sensing component 26d. During this condition the controller 22 may also send out an alarm message via the wireless communications radio 25 or via any other means, or may otherwise display an alarm message on a display thereof (if the controller 22 is configured with a display system). This opening of the primary vent valve 30 allows venting of the air pocket(s) within the force main line 20, which enables fluid being pumped from other ones of the pumps (i.e., pumps besides pump 12) to be discharged into and through the force main line 20. However, as soon as the controller 22 receives a signal from the sensing component 26d indicating that the poppet valve element 26b has moved to the fully raised position, the controller 22 knows that now only fluid is flowing through the poppet valve assembly 26, indicating that the air pocket(s) in the force main line 20 are no longer present. When this condition presents itself, the controller 22 then causes the primary vent valve 30 to close. Before the primary vent valve 30 closes fully, a small amount of fluid flows through the primary vent valve into the supplemental fluid tank 36.

[0028] The foregoing operations serve to automatically detect when the air supply valve within the pump 12 becomes stuck in the open position. When this condition occurs it causes compressed air to continue to be pumped into the force main line 20 after the quantity of fluid collected within the pump casing 12a has been pumped out of the pump casing. By periodically opening the primary vent valve 30 and using the poppet valve assembly 26 to check if fluid is flowing through the poppet valve assembly, the controller 22 can reliably detect if air has been pumped into the force main line 20, and can allow the air pocket(s) in the force main line to be vented.

[0029] Figure 2 shows a high level flowchart 100 of major operations that may be performed using the system 10 of Figure 1 during a single cycle of checking the force main line 20 for the presence of air pockets. At operation 102 the primary vent valve 30 is opened automatically (e.g., by the controller 22 or possibly by an external timer, or by external remote radio communications).

[0030] At operation 104 the signals from the sensing components 26c and 26d are read by the controller 22. At operation 106 the controller 22 uses the signals from the sensing components 26c and 26d to determine if the poppet valve element 26a is in its fully raised position. If the check at operation 108 produces a “NO” answer, then the controller 22 understands this is evidencing that only air is flowing through the poppet valve assembly 26, and the controller 22 holds the primary vent valve 30 in the open position, as indicated at operation 108, using a compressed air signal applied via the solenoid valve 24 to the primary vent valve. Operations 104 and 106 are then repeated.

[0031] If the check at operation 106 indicates that the poppet valve element 26a is either at the Home position or an intermediate position (i.e., no longer at the fully raised position), then the controller 22 uses this information to close the primary vent valve 30 (or alternatively to reset the external timer, if an external timer is being used, thus allowing the electrical primary vent valve to close).

[0032] In another embodiment, the system may be implemented with only a single magnetic sensing component, for example using only sensing component 26d. In this embodiment if the primary vent valve 30 is opened start a vent operation, and right away the controller 22 detects that the poppet is in the UP position (the sensing component 26d, such as a single reed sensor produces a “1 ” level signal indicating the poppet valve element is in the fully raised position), then the controller 22 will understand that there is no air in the force main line 20. In this situation, the controller 22, within a short time, for example within 0.5 seconds, closes the primary vent valve 30, and then waits 30 minutes to run the test again. But if the controller 22 reads a “0” signal from the sensing component 26d (e.g., a single reed sensor) as soon as the primary vent valve 30 is opened, or possibly within a very short time thereafter, for example within 1 second thereafter, this will indicate to the controller 22 indicating that the poppet valve element 26a has dropped from the fully raised position. The controller 22 will understand that air is blowing through the poppet valve assembly 26, and will hold the primary vent valve 30 open until it receives a “1 ” level signal from the single sensing component 26d (e.g., from the single reed sensor), which will indicate that the poppet valve element 26a is now in the fully raised position. So while the system 10 can be implemented with a single sensing component, the use of two sensing components (26c and 26d) does provide the “intelligence” for the controller 22 to verify that air is in fact blowing through the poppet valve assembly 26.

[0033] In still another embodiment the system 10 may be modified to incorporate a pressure transducer 21 , as shown in Figure 1 , in place of the poppet valve 26. The pressure transducer 21 in this embodiment is placed near the end of the force main line 20, near the water treatment facility, and communicates with the interior of the force main line. When the pressure within the force main line 20 rises to a pre-determined pressure point, for example 10 psi, the pressure transducer 21 detects this condition and generates a signal indicating the need to initiate a venting operation. This signal can be sent to open the primary vent valve 30 and vent the force main line 20. Possibly this signal (either wired or wireless) may be provided directly to the primary vent valve 30, assuming the primary vent valve is constructed and of the type to receive such an electrical signal. Alternatively, the signal (wired or wireless) may be provided to the controller 22 from the pressure transducer 21 , from which the controller determines that the primary vent valve 30 needs to be opened. Still further, if the pressure transducer 21 is used, it may even be possible to omit use of the poppet valve assembly 26, assuming that the pressure transducer (or multiple pressure transducers) can be configured to sense 1 ) when the pressure within the force main line 20 indicates air in the force main line, and also 2) when the pressure within the force main line 20 has dropped to a point indicating that only liquid exists in the force main line. In either case, when the pressure transducer 21 is used, there would be no need to periodically, routinely open the primary vent valve 30 to check for air in the force main line. The pressure transducer 21 thus may be used to limit the number of times the system 10 is vented. All of the above implementations are envisioned by the present disclosure.

[0034] It will also be appreciated that use of the pump 12 is not absolutely essential to achieve the detection of air in the force main line 20. The system 10 in its various embodiments, as described herein, may all be practiced where no pump is being used, but the implementation is such that it is still important to detect when a pressure has risen within a liquid flow conduit, due to pressurized air or air pockets having entered the liquid flow conduit, and to enable venting of the liquid flow conduit to the point where the air pocket(s) has/have been removed.

[0035] The system 10 thus provides a means for determining when air pockets are present in the force main line 20, as well as when any such air pocket(s) has/have been removed. This eliminates the situation where a single pump having its internal air supply valve stuck in the open condition can cause air to be pumped into the force main line which prevents other pumps feeding into the force main line from discharging their fluid contents into the force main line. [0036] The foregoing description of the embodiments has been provided for purposes of illustration and description. It is not intended to be exhaustive or to limit the disclosure. Individual elements or features of a particular embodiment are generally not limited to that particular embodiment, but, where applicable, are interchangeable and can be used in a selected embodiment, even if not specifically shown or described. The same may also be varied in many ways. Such variations are not to be regarded as a departure from the disclosure, and all such modifications are intended to be included within the scope of the disclosure.

[0037] Example embodiments are provided so that this disclosure will be thorough, and will fully convey the scope to those who are skilled in the art. Numerous specific details are set forth such as examples of specific components, devices, and methods, to provide a thorough understanding of embodiments of the present disclosure. It will be apparent to those skilled in the art that specific details need not be employed, that example embodiments may be embodied in many different forms and that neither should be construed to limit the scope of the disclosure. In some example embodiments, well-known processes, well-known device structures, and well-known technologies are not described in detail.

[0038] The terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting. As used herein, the singular forms “a,” “an,” and “the” may be intended to include the plural forms as well, unless the context clearly indicates otherwise. The terms “comprises,” “comprising,” “including,” and “having,” are inclusive and therefore specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. The method steps, processes, and operations described herein are not to be construed as necessarily requiring their performance in the particular order discussed or illustrated, unless specifically identified as an order of performance. It is also to be understood that additional or alternative steps may be employed.

[0039] When an element or layer is referred to as being “on,” “engaged to,” “connected to,” or “coupled to” another element or layer, it may be directly on, engaged, connected or coupled to the other element or layer, or intervening elements or layers may be present. In contrast, when an element is referred to as being “directly on,” “directly engaged to,” “directly connected to,” or “directly coupled to” another element or layer, there may be no intervening elements or layers present. Other words used to describe the relationship between elements should be interpreted in a like fashion (e.g., “between” versus “directly between,” “adjacent” versus “directly adjacent,” etc.). As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items.

[0040] Although the terms first, second, third, etc. may be used herein to describe various elements, components, regions, layers and/or sections, these elements, components, regions, layers and/or sections should not be limited by these terms. These terms may be only used to distinguish one element, component, region, layer or section from another region, layer or section. Terms such as “first,” “second,” and other numerical terms when used herein do not imply a sequence or order unless clearly indicated by the context. Thus, a first element, component, region, layer or section discussed below could be termed a second element, component, region, layer or section without departing from the teachings of the example embodiments.

[0041] Spatially relative terms, such as “inner,” “outer,” “beneath,” “below,” “lower,” “above,” “upper,” and the like, may be used herein for ease of description to describe one element or feature's relationship to another element(s) or feature(s) as illustrated in the figures. Spatially relative terms may be intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as “below” or “beneath” other elements or features would then be oriented “above” the other elements or features. Thus, the example term “below” can encompass both an orientation of above and below. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

Claims

CLAIMS What is claimed is:

1 . A system for monitoring for air in a force main line of a well system, wherein the force main line is collecting liquid from at least one fluid pump disposed in wellbore at a site, and enabling venting of the air from the force main line, the system comprising: a controller; a pneumatic fluid pump; a force main line in fluid communication with a discharge line of the pneumatic fluid pump; a valve assembly in fluid communication with the force main line, the valve assembly including an internal valve element movable between first and second positions in response to the presence of air or fluid flowing through the valve assembly, and the valve assembly configured to send signals to the controller indicative of whether the valve element is in the first or second position; a primary vent valve in communication with the valve assembly; and wherein the primary vent valve is periodically opened, and signals from the valve assembly are used by the controller to determine if air or liquid is flowing through the valve assembly, and to further control the primary vent valve in accordance with the signals provided by the first and second sensing components to enable venting of air from the force main line.

2. The system of claim 1 , wherein the valve assembly comprises a poppet valve assembly, and wherein the internal valve element comprises a poppet valve element.

3. The system of claim 2, wherein the poppet valve assembly further comprises: a magnet carried on the poppet valve element; a first sensing component for sensing a magnetic field provide by the magnet when the magnet is in a first position in proximity to the first sensing component; and a second sensing component spaced apart from the first sensing component and elevationally above the first sensing component, which senses the magnetic field provided by the magnet when the magnet is in a second position elevationally spaced apart from the first position, and adjacent the second sensing component.

4. The system of claim 3, wherein the first and second sensing components comprise Hall Effect Sensors.

5. The system of claim 1 , further comprising a solenoid valve operably associated with the controller, the solenoid valve being controlled by the controller to enable opening of the primary vent valve.

6. The system of claim 1 , further comprising a wireless communications radio operably associated with the controller for transmitting information related to a condition of the system to a remote subsystem.

7. The system of claim 1 , further comprising a local pressure transducer in communication with the force main line and with the controller, to detect a pressure within the force main line, the detected pressure within the force main line being indicative of a need to initiate a venting operation to vent the force main line using the primary vent valve.

8. The system of claim 7, wherein the controller receives a signal from the remote pressure transducer to trigger venting of the force main line using the primary vent valve.

9. The system of claim 1 , wherein the primary vent valve is a pilot operated, pneumatically controlled valve.

10. The system of claim 1 , wherein the primary vent valve comprises an electrically actuated valve controlled by the controller.

11 . A system for monitoring for air in a force main line of a well system, wherein the force main line is collecting liquid from at least one fluid pump disposed in wellbore at a site where the system is employed, and enabling venting of the air from the force main line, the system comprising: a controller; a pneumatic fluid pump; a force main line in fluid communication with a discharge line of the pneumatic fluid pump; a poppet valve assembly in fluid communication with the force main line, the valve assembly including: an internal poppet valve element movable elevationally between first and second elevationally spaced apart positions in response to the presence of air or liquid flowing through the valve assembly; and first and second sensing elements for sensing a position of the poppet valve element, and sending signals to the controller indicative of whether the valve element is in the first or second position; a primary vent valve in communication with the poppet valve assembly; and wherein the primary vent valve is periodically opened, and signals from the valve assembly are used by the controller to determine if air or liquid is flowing through the valve assembly, and to further control the primary vent valve in accordance with the signals provided by the first and second sensing components to enable air within the force main line to be vented therefrom.

12. The system of claim 11 , wherein the primary vent valve is controlled by the controller.

13. The system of claim 12, further comprising a solenoid valve controlled by the controller to apply a compressed air signal to the primary vent valve to selectively open the primary vent valve.

14. The system of claim 11 , further comprising a magnet secured to the poppet valve element.

15. The system of claim 14, wherein the first and second sensing components each comprise reed switches for sensing an elevation position of the magnet, and thus an elevational position of the poppet valve element.

16. The system of claim 11 , wherein the primary vent valve comprises an electrically actuated valve controlled by the controller.

17. The system of claim 11 , wherein the primary vent valve is a pilot operated pneumatic valve.

18. A method for monitoring for air in a force main line of a well system, wherein the force main line is collecting liquid from at least one fluid pump disposed in wellbore at a site, and enabling venting of the air from the force main line, the method comprising: using a valve system to receive a portion of a flow of at least one of air and liquid from the force main line; using a primary vent valve in communication with the valve system to vent the valve system; while the primary vent valve is venting the valve system, sensing a position of a movable valve element within the valve system to determine if liquid or air is flowing through the valve system; and when only fluid is detected as flowing through the valve system, closing the valve system.

19. The method of claim 18, further comprising periodically opening the primary vent valve in accordance with a predetermined time interval to check whether fluid or air flows through the valve system.

20. The method of claim 18, further comprising holding the primary vent valve open continuously until it is detected that only fluid is flowing through the valve system.

21. The method of claim 18, wherein the sensing a position of the movable valve element comprises magnetically sensing a position of the movable valve element using a pair of elevationally spaced apart magnetic sensing elements.

22. The method of claim 21 , further comprising using an electronic controller to receive electrical signals from the pair of magnetic sensing elements and to close the primary vent valve.

23. A system for monitoring for air in a force main line of a well system, wherein the force main line is collecting liquid from at least one fluid pump disposed in wellbore at a site, and enabling venting of the air from the force main line, the system comprising: a pneumatic fluid pump; a force main line in fluid communication with a discharge line of the pneumatic fluid pump; a pressure transducer in fluid communication with the force main line; a primary vent valve in communication with the force main line; and wherein the primary vent valve is opened when a signal from the pressure transducer indicates that a predetermined pressure within the force main line has been at least one of reached or exceeded, to enable venting of the force main line for a time sufficient to remove air from the force main line, before returning the primary vent valve to a closed position.