Tank fluid level measurement systems and methods

A tank volume measurement system and method. The tank volume measurement system receives a tank identifier indicating which tank the level sensor is sensing, receives a tank level indication from a level sensor, correlates the tank level to a tank volume using a calibrated strapping chart, and outputs a volume indication to a user.

BACKGROUND

Field of the Disclosure

The present disclosure relates generally to tanker truck fluid level measurement systems and methods. The systems and methods may include management capabilities related to filling, draining, and transport of fluids.

Description of the Related Art

Tanker trucks do not currently have an effective way of measuring the amount of fluid that is in a tank of a tanker truck. One method of measuring the fluid in a tanker is by placing the truck on a scale when it is empty and again when it is full and determining how many gallons are in the tank by weight and specific gravity of the fluid. Weighing trucks in certain industries, including the oil and gas industry, is seldom used, however, at least because the weight of fluids can vary greatly and because it is impracticable to put a scale at every gas and oil extraction site, such as drill pads.

Other methods of measuring fluid in a tank are through the use of level gauges and monitoring systems. Those systems are very inaccurate and do not reflect the correct quantity of liquid being hauled, however. Tanks on trucks are typically manufactured with inherent variability, often due to inconsistency in the raw materials used to manufacture the tank. The volume of each tank varies from one tank to the next even though they may be labeled the same container size. The same tank often varies +/−3-5% in volume due to manufacturing differences. Moreover, tanker trucks that desire to measure fluid level currently use several different types of gauges and monitoring systems. All of those systems provide an approximation of volume and do not accurately measure the tank liquid volume or take into account inaccuracies, such as tank manufacturing variances. Thus, the volumes of tanker truck tanks commonly differ from 10-15% when measured by various existing methods. Measuring systems that assume that all tanks are equivalent likely do not account for tank discrepancies and imbedded assumptions, such as equivalent tank capacities, ripple through existing measuring systems resulting in inaccurate tank level measurement.

Another method used to determine fluid volume in a tanker truck is to measure the volume of fluid placed into the tank when it is filled. When such a method is employed, a flow meter may measure the volume of liquid being placed in the tank. This volume measurement method is sometimes used in industries such as hauling gasoline and chemicals.

The use of flow meters to measure the volume of fluid placed into or removed from a tank is not practical in certain industries, either, because, for example, it may be expensive, time consuming, or otherwise impractical to include a flow meter at each extraction site to monitor fluid flow into or out of a truck.

Truck monitoring gauges are also employed in known systems. Those gauges use an interior float to measure fluid level. Those gauges are also inaccurate, however, because the float changes the level of the fluid itself and variances in fluid specific gravity and varying tank dimensions contribute to error.

Yet another volume measurement system uses an external sight glass to determine fluid level in a tank, however sight glasses only provide level approximations and do not provide an output capable of being utilized by an asset monitoring system or program.

For at least the foregoing reasons, it is desirable to have an improved tanker truck fluid level measurement system.

It is also desirable to have an improved tanker truck fluid volume measurement system.

It would also be advantageous to include fluid transfer management capabilities in a tank filling or draining system.

In addition, it would be advantageous to identify the location of a tanker truck that is filling or draining.

It would also be advantageous to have a system for creating a custom strap chart for a specific tanker truck.

It would also be advantageous to have a user interface to receive information from the measurement systems discussed herein.

It would also be beneficial to have indictors that indicate to an operator when a truck tank is nearly full and when the truck tank is full.

It would be beneficial to automatically shut-off flow to a tank when that tank is nearly full.

A measurement system that controls an amount of pressure applied to a tank based on the level of fluid in the tank or the volume of fluid in the tank would also be beneficial.

Accordingly, the present invention provides solutions to the shortcomings of prior tanker truck filling and draining systems, apparatuses, and methods. Those of ordinary skill in the art will readily appreciate, therefore, that those and other details, features, and advantages of the present invention will become further apparent in the following detailed description of the preferred embodiments of the invention.

SUMMARY OF THE INVENTION

In an embodiment, a tanker truck volume measurement system includes a processor having access to a plurality of strap charts and coupled to a level sensor. One strap chart exists for every tank in which fluid volume is to be measured and each strap chart correlates a level of fluid in a particular tank to a volume of fluid held by that tank at that level. The level sensor is mounted adjacent to the tank currently being loaded or unloaded and may be removable for use on various tanks. The processor includes instruction which, when executed by the processor, cause the processor to receive a tank identifier indicating which tank the level sensor is sensing, receive a tank level indication from the level sensor, correlate the tank level to a tank volume using the strap chart for the tank having its level sensed, and output the volume that correlates to the sensed level in that tank, making that volume accessible to a user.

In another embodiment, a tanker truck volume measurement system that includes a processor having access to a plurality of strap charts and coupled to a level sensor receives a unique identifier for a tank in position to be filled, receives periodic fluid level measurements in the tank, and correlates the level of fluid in the tank to a volume of fluid in the tank by referencing a strap chart prepared for the specific tank having its level. The processor then provides indicators to assist the tank truck operator in knowing when the tank is full, empty or at a desired level. Those indicators include a first indicator that indicates when the tank is less than full by a volume of a fill hose and a second indicator that indicates when the tank is full. In an embodiment, the indicators may include illuminating different colored lights and sounding an audible indicator.

A method of operating a latch is also provided. That method includes receiving an identifier for a tank, receiving a level of fluid in the tank, correlating the level of fluid to a volume of fluid using a strap chart prepared for the specific tank having its level sensed, and outputting the volume that correlates to the sensed level in that tank.

Other embodiments, which may include one or more portions of the aforementioned apparatuses and methods or other parts or elements, are also contemplated, and may have a broader or different scope than the aforementioned apparatuses and methods. Thus, the embodiments in this Summary of the Invention are mere examples, and are not intended to limit or define the scope of the invention or claims.

DETAILED DESCRIPTION

As employed herein, the term “number” shall mean one or an integer greater than one (e.g., a plurality).

Any reference in the specification to “one embodiment,” “a certain embodiment,” or a similar reference to an embodiment is intended to indicate that a particular feature, structure or characteristic described in connection with the embodiment is included in at least one embodiment of the invention. The appearances of such terms in various places in the specification do not necessarily all refer to the same embodiment. References to “or” are furthermore intended as inclusive, so “or” may indicate one or another of the ored terms or more than one ored term.

FIG.1illustrates a tanker truck fluid level measurement system2with management capabilities, in accordance with one non-limiting embodiment of the disclosed tank management system. The tanker truck fluid level measurement system2includes a tanker truck10having a tank12and a level sensor30mounted adjacent to the tank. A processor-based device20communicates with the level sensor30. The processor-based device20may be coupled to the level sensor30by wires or wirelessly. The truck10in this embodiment also includes a global positioning device40, which may determine the relationship of the truck10to various gas or oil sites or drill pads46and48, possibly using geofencing technology42and44arranged to identify those sites46and48.

The processor-based device20may be a general-purpose computer; a tablet; a mobile smartphone, referred to herein as a phone; an application specific user interface device; or another device that can be used to transfer information to the tanker truck fluid level measurement system2or receive information from the tanker truck fluid level measurement system2.

The level sensor30may be any desired level measuring device, including, for example, a radar level sensor discussed herein, a float type level sensor, a capacitive type level sensor, a sensor that converts pressure into level, or any other type of sensor desired. The level sensor30may be mounted adjacent to the tank, for example a radar sensor mounted in or near the top or the tank12, a pressure sensor mounted in the bottom of the tank, or a float sensor mounted in a tube in fluid communication with the tank12. Moreover, the level sensor30may be permanently attached to the tank12or may be removable from the tank12for use on another tank12or reuse on the same tank12at another time.

In an embodiment, the level sensor30, is a radar-based device and is mounted inside the top of the tank12. The radar device level measuring device may have an accuracy of 2 mm or 0.08″, and may be mounted internally near the top of the tank12and near the center of the tank12. Such a radar device may utilize 80 GHz radar, so that the radar device is small, compact, and light (possibly approximately 1.4 lbs.). The radar device may be center mounted underneath a main hatch of the tank12for protection. The radar device may point down into the tank12and shoot a radar beam to measure the liquid level height. The radar device may be advantageous because it may be extremely accurate in terms of providing the level of the liquid height in the tank12.

FIG.2illustrates an embodiment of the processor-based device20. In that embodiment, the processor-based device20includes a processor212and a communication device214. The processor20and communication device214can be combined in a microprocessor or other device and other components (e.g.,220and236) may also be included in such a microprocessor or other device.

The communication device214may be wired to a device to which it communicates; the communication device214may wirelessly communicate with one or more other devices over a network240; which may be a wireless network, such as a mobile smartphone network; and the communication device214may operate both wired and wirelessly. The processor-based device20may furthermore include memory220, an input224that may receive an input signal, such as a signal transmitted by a sensor, and an output226that may transmit a control signal, instruction, or data to another device, such as a valve actuator or other controlled device. The output device may alternatively or in addition provide a reading, for example a current volume of fluid in the tank12, which may be mounted on or near a tank12that is being loaded or unloaded.

The processor-based device20may also be coupled to a user interface218to receive one or more signals from, for example, one or more of a keyboard, touch screen222, mouse, microphone or other input device or technology and may have associated software. The user interface may also transmit information to, for example, a printer or screen222coupled to the user interface218or the output226.

The memory220may, for example, include random-access memory (RAM), flash RAM, dynamic RAM, or read only memory (ROM) (e.g., programmable ROM, erasable programmable ROM, or electronically erasable programmable ROM) and may store computer program instructions and information. In embodiments, the memory220may be partitioned into sections including an operating system partition232where system operating instructions are stored, and a data partition239in which data, such as one or more strap charts300is stored.

The storage device236may include a memory device or a data storage device or a combination of both memory and data storage devices, or another device or devices for storage of data. The data storage236may be considered local storage when the data is stored directly on the processor-based device20or the data may be accessible to the processor-based device20over a wired or a wireless network. The storage device236may furthermore include a computer readable storage medium that includes code executable by the processor212of the tanker truck fluid level measurement system2that causes the processor212to, at least in part, perform as disclosed herein.

In an embodiment, the storage for the processor-based device20may include a combination of flash storage and RAM. The storage may include a computer readable storage medium and may include code executable by the processor212.

In an embodiment, the elements, including the processor212, communication adaptor218, memory220, input device224, output device226, and data storage device236may communicate by way of one or more communication busses230. Those busses230may include, for example, a system bus or a peripheral component interface bus.

The processor212may be any desired processor and may be a part of a controller16, such as a microcontroller, may be part of or incorporated into another device, or may be a separate device. The processor212may, for example, be an Intel® manufactured processor or another processor manufactured by, for example, AMD®, DEC®, or Oracle®. The processor212may furthermore execute the program instructions and process the data stored in the memory220. In one embodiment, the instructions are stored in the memory220in a compressed or encrypted format. As used herein the phrase, “executed by a processor,” is intended to encompass instructions stored in a compressed or encrypted format, as well as instructions that may be compiled or installed by an installer before being executed by the processor212.

The data storage device236may be, for example, non-volatile battery backed static random-access memory (RAM), a magnetic disk (e.g., hard drive), optical disk (e.g., CD-ROM) or any other device or signal that can store digital information. The data storage device236may furthermore have an associated real-time clock, which may be associated with the data storage device236directly or through the processor212. The real-time clock may trigger data from the data storage device236to be sent to the processor212, for example, when the processor212polls the data storage device236. Data from the data storage device236that is to be sent across the network240through the processor212may be sent in the form of messages in packets if desired. Those messages may furthermore be queued in or by the processor212.

The communication adaptor218permits communication between the processor-based device20and other nodes, such as a tanker truck controller35, which may be associated with the level sensor30, or a remote monitoring peripheral computer37or server, both illustrated inFIG.4. The communication adaptor218may be a network interface that transfers information from a node such as a networked device, which would include an actuating device such as valve60or a sensing device, such as level sensor30, the tanker truck controller35, the remote monitoring peripheral computer37, a general purpose computer (not illustrated), a user interface device, such as the processor-based device20depicted inFIGS.1and2, or another node. The communication adaptor218may be an Ethernet adaptor or another adaptor for another type of network communication. It will be recognized that the processor-based device20may alternately or in addition be coupled directly to one or more other devices through one or more input/output adaptors (not shown).

The processor212may contain in its memory220or data storage device226, or may communicate with another node or data storage device to access, a plurality of strap charts300, an example of which is illustrated inFIG.3. The strap charts300may equate the level of fluid in a tank12to the volume of fluid in that tank12, establishing a simple and accurate way to determine the volume of fluid in a tank12. A separate strap330chart may exist for each of a variety of tanks12from which the processor-based device210receives information. For example, a first tanker truck10may include a tank12and a unique identifier may be associated with that tank12or the truck10on which the tank10is situated.

The tank identifier may be any unique identifier of the tank12or the truck10on which a particular tank12is mounted and may be recognized in a variety of ways. For example, a user interface may be used to identify the tank currently in position to operate (e.g., load or unload), may be transmitted by the tank12or associated truck10by any signal transmitting device, or may be read and transmitted by a geofencing42,44or other position determination device that senses the presence of the tank12or its associated truck10.

Because of the variances that may occur through manufacturing, use, and damage, for example, to each tank12on each truck10, the volume of a variety of tanks12, potentially every tank12, at various levels may be desired to be determined. To provide the volume of the liquid in the tank12, each tank12may be separately calibrated. Such calibration may use a calibration pump skid and each calibration pump skid may utilize a flowmeter62(illustrated inFIG.4) to measure an amount of fluid placed in the tank12. The amount of fluid placed in the tank12may be associated with a level of the fluid in the tank12to create a strap chart220for that tank that provides the volume of fluid in the tank12as an output to a user or device when the level of fluid in the tank is provided as an input by a user or device. For example, in one embodiment, the level of the fluid may be measured each time a barrel of fluid is placed in the tank12and the volume of fluid that has been placed in the tank12may be associated with the current fluid level in the tank12in a table or strap chart300so that the number of barrels of fluid in the tank12may thereafter be determined by reading from the strap chart300the volume that corresponds to the fluid level in the tank12.

In one embodiment, the flowmeter62may be a National Institute of Standards and Technology (NIST) certified calibrated flowmeter that is calibrated to be accurate to 0.02%. That flowmeter62may be employed to achieve an accuracy of + or − less than 10 gallons and may be accurate to 1 gallon in a nominal 110 bbl tank. The strap chart300may be established in the processor-based device20in the form of a two-dimensional array or other database format. The calibrated accuracy of the combined flow meter62and strap chart300can be correlated to the overall accuracy of the level system, creating a calibrated level system by proxy.

It may furthermore be noted that water may, for example, be placed in the tank12to create the strap chart330, but any liquid may thereafter be placed in the tank12and the volume of the tank12may be measured using a level sensor30and the strap chart300. Fluids that may be measured in the tank using the disclosed system may include, but are not limited to, oil, gasoline, water, milk, water mixed with various other solids and liquids, or any other fluid or other substance that may be transported via a tank.

The custom calibrating pump skid disclosed herein may be used when filling the tank12during a calibration phase. At the same time the tank12is being filled, the radar or other level measuring device30will measure the liquid level in the tank12and the processor-based device20can develop a custom strap chart300for the tank12as the liquid is placed into the tank12.

FIG.3illustrates a level vs. volume table300, also called a strap chart, for a particular tank12. The strap chart300may thereafter be used for level/volume correspondence for that tank12for the life of that tank12or until a modification is made to that tank12. Similarly, other tanks12could be calibrated on the pump skid and have custom strap charts300attached to them for use throughout the life of those tanks12. Accordingly, in the future, when the level device30reads the liquid level, it may compare the level sensed to the custom strap chart300for that tank12and identify the exact volume of liquid in the tank12from the level of the fluid in that tank12. In that way, variations in tank manufacturing are advantageously irrelevant due to use of the custom strap chart300developed for each tank12. Furthermore, the tank calibration is performed independent of the type of liquid in the tank12, as chemical composition does not impact the readings or volume.

In an embodiment, a plurality of strap charts300is accessible by the processor-based device20, one strap chart300existing for every tank12in which fluid volume is to be measured. Each strap chart300correlates a level of fluid in a particular tank12to a volume of fluid held by that tank12at that level.

FIG.4illustrates another embodiment of a tanker truck volume monitoring system402. The tanker truck fluid level measurement system402includes a tanker truck10having a tank12, a transfer hose64that can carry fluid either to the tank12or away from the tank12, a processor-based device20, a level sensor30, an indicator40, a breather valve50, and a fluid valve60. The volume monitoring system ofFIG.4includes an indicator package to assist an operator in filling the tank12. In one embodiment, the system402contains an indicator package that includes two indicator lights that are used for an indicator40in this embodiment. The first light on the indicator40may illuminate when the tank12is almost full (e.g., 5 barrels less than full) and the second light on the indicator40may illuminate when the tank is full or very nearly full. The first light on the indicator40may, for example, be yellow and may be used to direct the operator to close a valve on a production tank from which the fluid is being pumped or otherwise transferred into the tank12of the truck10. After stopping the flow of fluid from its source, the operator may empty a transfer hose64communicating between the fluid source and the tank12into the tank12. For example, the operator may open a breather valve50on the tank12and drain the transfer hose64into the tank12. The truck10may draw a vacuum during tank12filling and may continue to draw the vacuum when draining the transfer hose64, thereby draining the fluid from the transfer hose64into the tank12.

The second light on the indicator40may illuminate when the tank12is full or very nearly full. The operator may then cease placing fluid in the tank12and shut the production water valve60and the breather valve50, thus yielding a full tank12of fluid. As such, the first and second lights on the indicator40advantageously assist the driver or other operator to know when to stop filling the tank12and shut the valve60on the tank12so the truck10is filled accurately and fully. Other light functionality may also or alternatively be included to indicate empty status or other important points in the filling or emptying process.

In an embodiment, various color indicator40lights turn on at the rear of the truck10during the filling operation to assist the driver or operator. A yellow light illuminates on the indicator40on when the truck is almost full (i.e., 5 bbls to full) and a red light illuminates on the indicator40to direct the driver to close the incoming production water valve60. The operator then opens a ½″ breather valve50on the tank12and empties the transfer hose64into the tank12.

Truck10tanks12and the vessels they are loading from or unloading into may be pressurized to enhance that process. For example, when a truck10tank12is unloading, the tank12may be pressurized to assist in moving fluid out of the tank12or a vessel the tank12is unloading into may create a vacuum or negative pressure to assist in drawing the fluid out of the tank12. Conversely, when the tank12is being loaded, a vessel providing fluid to the tank12may be pressurized to assist the fluid in moving from the vessel to the tank12or the tank12may draw a vacuum to assist in moving the fluid from the vessel to the tank12. In various embodiments, the truck10may continue to operate and pull vacuum until the transfer hose64is empty to drain the fluid in the transfer hose64into the tank12. The operator may then shut the production water valve60and should have a full load of fluid.

In embodiments, the level sensor may be used to adjust the pressure or vacuum applied to the tank12or the vessel. For example, when the tank12is draining, the volume monitoring system402may provide a signal to an apparatus pressurizing the tank12reducing the pressure applied in the tank12as the level or volume of the tank12is reduced. When the tank12is filling, the volume monitoring system402may provide a signal to an apparatus creating a vacuum in the tank to reduce the vacuum when the tank12nears full.

It should be recognized that any number of lights may be included on the indicator40to indicate fluid level in the tank12and thereby to assist the operator in filling the tank12. It should furthermore be recognized that indicators40other than lights or in addition to lights may be employed. For example, an audible indicator may be employed to attract the attention of the operator and warn the operator that the tank12is nearing its full fill point. In certain embodiments, a combination of an audible indicator, a light indicator, and possibly other indicators are included in the system2indicator40to gain the attention of the operator when the tank is nearly full.

Furthermore, in accordance with the disclosed concept, the production water valve60may be automated to close-off flow to or from the tank12at a predetermined time associated with tank12level. Accordingly, the lighting package may operate as described hereinabove, and the automated valve60may automatically close when a pre-set tank12fill level is reached. Automatic closure of the production water valve60advantageously prevents the tank12from overfilling and scrubbing out.

A fill-level other than completely full for a tank12can alternatively be pre-set so that the production water valve60closes automatically when that preset level is reached, in embodiments in which a full tank12is not desired, for example when the truck10is to travel roads that do not permit the weight of a full tank12load of fluid. One example of when the aforementioned may be applied advantageously is where a 110 bbl truck is not permitted to carry 110 bbls of fluid to a particular location, such as a site in Ohio where a driver must carry no more than 64 bbls per load due to weight restrictions. In the past it has been difficult to determine if there were 64 bbls on the truck, but using the present fluid level measurement system, the driver or operator can pre-set 64 bbls to be transferred into the tank12and the automatic valve60will close when the tank12load reaches 64 bbls.

Where indicator40lights are used in such a less than full load embodiment, the first light on the indicator40may illuminate when the tank12is approximately 64 barrels less the volume of the transfer hose64so the operator can stop flow through the transfer hose64from the fluid source and empty the transfer hose64into the truck10tank12at that time. The second indicator40light may illuminate when the tank12is filled with 64 barrels of fluid to indicate that the tank12is full to the desired volume. In certain embodiments, the processor212may have stored or receive a quantity of fluid held by the transfer hose64and may determine when to indicate that fluid transfer should cease based on the difference between the capacity of the tank12and the capacity of the transfer hose64.

In accordance with the disclosed system, the amount of fluid in the tank12can advantageously be determined with precision. Once that is known, reports can be generated for invoicing and billing purposes, regulatory reporting purposes, safety purposes (e.g., if the truck10would have an accident the responders will know exactly how much liquid is in the truck10) and other desired purposes.

The level reading may be transmitted to one or more computerized devices for processing. For example, the level may be sensed by a level sensor30and the level may be transmitted electronically to a computerized device, such as the processor-based device20, that uses the strap chart302for that tank12to determine the volume of fluid contained in the tank12. In an embodiment, the level sensor30is a radar unit and the level is wirelessly transmitted via Bluetooth or another form of transmission to a level gauge located at the rear of the truck10, a level gauge in the cab of the truck10, or to an external user interface, such as a computer, a phone20shown in simplified form inFIG.1, a tablet, or another electronic device. The processor-based device20may also receive the level from the level sensor30and generate volume data for the fluid for tracking purposes or other purposes. Regulatory reports, Bills of Lading, and other documentation may be automatically be generated from the processor-based device20or another device based on the information received and determined by the device20or another device. For example, the volume of water discharged at a site by each truck that discharged water at that site may be provided electronically or in printed form by the device20

Alternatively, or in addition, the level sensor30may transmit to another device, an electronic signal that corresponds to an output signal provided by the level sensor30, such as an electronic signal that corresponds to a 4-20 mA signal. In an embodiment, a wireless device, such as a Bluetooth device, is enabled to capture 4-20 mA signal from a radar-based level sensor30or another level sensing device. The radar-based level sensor30senses the level of the fluid in the tank12and transmits that level to the wireless device via a 4-20 mA signal. That signal is then referenced against the calibrated strap chart and the volume of fluid held in the tank12is produced, for example in gallons or barrels, from the level and the strap chart.

It is also contemplated herein that the system2may be employed with a number of geo-fences200,300, shown in simplified form in dashed line drawing inFIG.1to determine the location of the truck10when it loads or unloads. For example, reference numerals210,310denote well pads configured to contain oil that the truck10will obtain. As shown, surrounding each well pad210,310is a corresponding one of the geo-fences200,300, a virtual fence that may include GPS coordinates of the location of the well pads210,310. Additionally, as shown, the truck10may also have a GPS system100, shown in simplified form and the location of the truck10may be determined from the GPS system100. Using that system, when a truck10that arrives at well pad210, the GPS system100will indicate that the truck10is on the geo-fence200. Accordingly, when the truck10arrives at the geo-fence200, the geo-fence200will advantageously be able to know that the truck10was previously at, for example, the geo-fence300. This makes tracking the fluid in the truck10significantly easier. Once the fluid is moved to a new well pad210,310, the truck10is registered at the new geo-fence200,300, which is recorded for the specific truck. In this manner, the travel path and distribution or accumulation of the liquid in the tank12can be recorded and monitored.

FIG.5illustrates a method500of measuring the volume of a tanker truck10tank12performed by a processor212. At502, a tank identifier indicates to the processor212which tank12the level sensor30is sensing, the level sensor30providing a signal corresponding to the level of fluid in that identified tank12. At504, the level sensor30provides a signal to the processor212corresponding to the level of fluid in the identified tank12and the processor212receives that level signal. At506, the processor212correlates the level of the fluid to a strap chart300for the identified tank12, the strap chart300having been previously created and stored for access by the processor. At508, the processor212provides an output representing the volume of fluid that corresponds to the level of fluid indicated for the tank12, the volume correlating to level in the strap chart300.