Collapsible particulate matter container

In accordance with presently disclosed embodiments, a collapsible and optionally stackable storage container for bulk material is provided. The disclosed storage container includes a collapsible frame defined by a rigid upper support structure, a rigid lower support structure and a support member coupled at one end to the upper support structure and coupled at another end to the lower support structure. An actuator is also provided which is coupled to the support member at one end. The disclosed storage container further includes a storage sack having an upper portion coupled to the upper support structure and a lower portion coupled to the lower support structure. The lower portion of the storage sack is generally taper-shaped and may be equipped with a discharge opening that enables release of the bulk material onto a conveyor, which may be employed when the collapsible storage container is integrated into a bulk storage system.

CROSS-REFERENCE TO RELATED APPLICATION

The present application is a U.S. National Stage Application of International Application No. PCT/US2015/045019 filed Aug. 13, 2015, which is incorporated herein by reference in its entirety for all purposes.

TECHNICAL FIELD

The present disclosure relates generally to transferring dry bulk materials, and more particularly, to a transportable particulate matter container which is collapsible.

BACKGROUND

During the drilling and completion of oil and gas wells, various wellbore treating fluids are used for a number of purposes. For example, high viscosity gels are used to create fractures in oil and gas bearing formations to increase production. High viscosity and high density gels are also used to maintain positive hydrostatic pressure in the well while limiting flow of well fluids into earth formations during installation of completion equipment. High viscosity fluids are used to flow sand into wells during gravel packing operations. The high viscosity fluids are normally produced by mixing dry powder and/or granular materials and agents with water at the well site as they are needed for the particular treatment. Systems for metering and mixing the various materials are normally portable, e.g., skid- or truck-mounted, since they are needed for only short periods of time at a well site.

The powder or granular treating material is normally transported to a well site in a commercial or common carrier tank truck. Once the tank truck and mixing system are at the well site, the dry powder material (bulk material) must be transferred or conveyed from the tank truck into a supply tank for metering into a blender as needed. The bulk material is usually transferred from the tank truck pneumatically. More specifically, the bulk material is blown pneumatically from the tank truck into an on-location storage/delivery system (e.g., silo). The storage/delivery system may then deliver the bulk material onto a conveyor or into a hopper, which meters the bulk material through a chute into a blender tub.

Recent developments in bulk material handling operations involve the use of portable containers for transporting dry material about a well location. The containers can be brought in on trucks, unloaded, stored on location, and manipulated about the well site when the material is needed. The containers are generally easier to manipulate on location than a large supply tank trailer. The containers are eventually emptied by dumping the contents thereof onto a mechanical conveying system (e.g., conveyor belt, auger, bucket lift, etc.). The conveying system then moves the bulk material in a metered fashion to a desired destination at the well site.

DETAILED DESCRIPTION

Certain embodiments according to the present disclosure may be directed to containers and systems for efficiently managing bulk material (e.g., bulk solid or liquid material) delivery to a well site. Bulk material handling systems are used in a wide variety of contexts including, but not limited to, drilling and completion of oil and gas wells, concrete mixing applications, agriculture, and others. The disclosed embodiments are directed to containers and systems for efficiently moving bulk material into a blender inlet of a blender unit at a job site. The collapsible and optionally stackable containers are designed to be efficiently delivered to a well site and returned to a central location for refilling. The bulk material systems are designed to include a plurality of the collapsible containers which may be modularly loaded onto a skid, which can be efficiently delivered to the well site. The disclosed techniques may be used to efficiently handle any desirable bulk material having a solid or liquid constituency including, but not limited to, sand, proppant, gel particulate, diverting agent, dry-gel particulate, liquid additives and others.

In currently existing on-site bulk material handling applications, dry material (e.g., sand, proppant, gel particulate, or dry-gel particulate) may be used during the formation of treatment fluids. In such applications, the bulk material is often transferred between transportation units, storage tanks, blenders, and other on-site components via pneumatic transfer, sand screws, chutes, conveyor belts, and other components. Recently, a new method for transferring bulk material to a hydraulic fracturing site involves using portable containers to transport the bulk material. The containers can be brought in on trucks, unloaded, stored on location, and manipulated about the site when the material is needed. These containers generally include a discharge gate at the bottom that can be actuated to empty the material contents of the container at a desired time.

In existing systems, the containers are generally supported above a mechanical conveying system (e.g., moving belt, auger, bucket lift, etc.) prior to releasing the bulk material. The discharge gates on the containers are opened to release the bulk material via gravity onto the moving mechanical conveying system. The mechanical conveying system then directs the dispensed bulk material toward a desired destination, such as a hopper on a blender unit. Unfortunately, this process can release a relatively large amount of dust into the air and result in unintended material spillage. In addition, the mechanical conveying system is generally run on auxiliary power and, therefore, requires an external power source to feed the bulk material from the containers to the blender.

The material handling systems having the portable and collapsible support structure disclosed herein are designed to address and eliminate the shortcomings associated with existing container handling systems. The portable support structure includes a frame for receiving and holding one or more portable collapsible and optionally stackable bulk material containers in an elevated position proximate the blender inlet (e.g., blender hopper or mixer inlet), as well as one or more gravity feed outlets for routing the bulk material from the containers directly into the blender inlet. In some embodiments, the portable support structure may be transported to the well site on a trailer, unloaded from the trailer, and positioned proximate the blender unit. In other embodiments, the portable support structure may be a mobile support structure that is integrated into a trailer unit. The portable support structure may be designed with an open space at one side so that the blender unit can be backed up until the blender inlet is in position directly under the gravity feed outlet(s) of the support structure.

The disclosed portable support structure may provide an elevated location for one or more bulk material containers to be placed while the proppant (or any other liquid or solid bulk material used in the fluid mixtures at the job site) is transferred from the containers to the blender. The support structure may elevate the bulk material containers to a sufficient height above the blender inlet and route the bulk material directly from the containers to the blender inlet. This may eliminate the need for any subsequent pneumatic or mechanical conveyance of the bulk material (e.g., via a separate mechanical conveying system) from the containers to the blender. This may improve the energy efficiency of bulk material handling operations at a job site, since no auxiliary power sources are needed to move the material from the containers into the blender inlet. In addition, the portable support structure may simplify the operation of transferring bulk material, reduce material spillage, and decrease dust generation.

Turning now to the drawings,FIG. 1is a block diagram of a bulk material handling system10illustrating the collapsible storage containers in accordance with present disclosure in a stacked configuration. As those of ordinary skill in the art will appreciate, the collapsible storage containers in accordance with present invention may or may not be stacked. The system10includes collapsible storage container12, which will be described in further detail below, which is elevated on a portable support structure14and holding a quantity of bulk material (e.g., solid or liquid treating material). The portable support structure14may include a frame16for receiving and holding the container12and a gravity-feed outlet18for directing bulk material away from the container12. The outlet18may be coupled to and extending from the frame16. The outlet18may utilize a gravity feed to provide a controlled, i.e., metered, flow of bulk material from the container12to a blender unit20.

As illustrated, the blender unit20may include a hopper22and a mixer24(e.g., mixing compartment). The blender unit20may also include a metering mechanism26for providing a controlled, i.e. metered, flow of bulk material from the hopper22to the mixer24. However, in other embodiments the blender unit20may not include the hopper22, such that the outlet18of the support structure14may provide bulk material directly into the mixer24.

Water and other additives may be supplied to the mixer24(e.g., mixing compartment) through a fluid inlet28. As those of ordinary skill in the art will appreciate, the fluid inlet28may comprise more than the one input flow line illustrated inFIG. 1. The bulk material and liquid ingredients may be mixed in the mixer24to produce (at an outlet30) a fracing fluid, a mixture combining multiple types of proppant, proppant/dry-gel particulate mixture, sand/sand-diverting agents mixture, cement slurry, drilling mud, a mortar or concrete mixture, or any other fluid mixture for use on location. The outlet30may be coupled to a pump for conveying the treating fluid to a desired location (e.g., a hydrocarbon recovery well) for a treating process. It should be noted that the disclosed system10may be used in other contexts as well. For example, the bulk material handling system10may be used in concrete mixing operations (e.g., at a construction site) to dispense aggregate from the container12through the outlet18into a concrete mixing apparatus (mixer24). In addition, the bulk material handling system10may be used in agriculture applications to dispense grain, feed, seed, or mixtures of the same.

It should be noted that the disclosed container12may be utilized to provide bulk material for use in a variety of treating processes. For example, the disclosed systems and methods may be utilized to provide proppant materials into fracture treatments performed on a hydrocarbon recovery well. In other embodiments, the disclosed techniques may be used to provide other materials (e.g., non-proppant) for diversions, conductor-frac applications, cement mixing, drilling mud mixing, and other fluid mixing applications.

As illustrated, the container12may be elevated above an outlet location via the frame16. The support structure14is designed to elevate the container12above the level of the blender inlet (e.g., blender hopper22and/or mixing tub24) to allow the bulk material to gravity feed from the container12to the blender unit20. This way, the container12is able to sit on the frame16of the support structure14and output bulk material directly into the blender unit20via the gravity feed outlet18of the support structure14.

Although shown as supporting a single container12, other embodiments of the frame16may be configured to support multiple containers12. In particular, the frame structure16may be a skid or other transportation unit. One such exemplary transportation unit is the Mountain Mover® trailer system marketed by the present assignee. The Mountain Mover® trailer has a bin capable of storing 2,500 ft3(70.8 m3) of proppant and is equipped with a self-contained hydraulic power package. A portable level sensor and automatic remote controls help to maintain a constant sand level in the hopper when discharging. The Mountain Mover® unit allows operators to manage inventory and have the gates open in a specific sequence. The unit may optionally be equipped with a hydraulic backup system that can be run by another comparably equipped Mountain Mover® unit or a separately provided hydraulic power package. The collapsible storage containers12in accordance with the present disclosure may be utilized to make up the storage bin area of the existing Mountain Mover® storage system. The exact number of containers12that may be implemented in such a system may depend on a combination of factors such as, for example, the volume, width, and weight of the containers12to be disposed thereon.

In any case, the container(s)12may be completely separable and transportable from the frame16, such that any container12may be selectively removed from the frame16and replaced with another container12. That way, once the bulk material from the container12runs low or empties, a new container12may be placed on the frame16to maintain a steady flow of bulk material to an outlet location. In some instances, the container12may be closed before being completely emptied, removed from the frame16, and replaced by a container12holding a different type of bulk material to be provided to the outlet location. The collapsible nature of the container12enables transportation the containers to be stacked when transporting back to the material source location. By being able to collapse the containers12, multiple containers can occupy the space previously occupied by a single container. This enables efficient use of space and resources at the well site location. It also helps to minimize traffic into and out of a well site, which can be challenge to manage in certain remote and tight locations.

Turning toFIG. 2, the details of the collapsible and optionally stackable bulk storage container12in accordance with the present disclosure is shown. Preferably, the container12is designed to hold 100-500 cubic feet of proppant. The bottom structure of the container12is also optionally designed to have a construction where a fork lift can be used to move the full or empty container, as further explained below. For practical purposes, the bottom of the container12may have a conical shape, e.g., 20-30 degrees square cone, for better downward flow of the particulate matter, as illustrated in the bottom half of the drawing shown inFIG. 2. While steeper angles may be better for the particulate flow, this cone could be equipped with one or more sonic or ultrasonic vibrators to help particles to slide easily downward. The walls of the containment portion of the container12(later referred to as the storage sack) may be, in one exemplary embodiment, made of cloth, which could be made of a woven nylon or glass, covered (or dipped) with nitrile rubber/elastomer. The conical-shaped section of the containment portion of the container12may be formed of the same cloth material as the walls.

The collapsible container12is preferably constructed such that the top frame, which may be a rectangular or in one exemplary embodiment a square shape, has a matching construction or shape on the bottom (the bottom frame), and when folded, securely locks the bottom frame to the top frame, while at the same time safely containing/protecting the soft structure of the containment portion (storage sack) between the two stiff/rigid top and bottom frames.

The top frame houses a port, which may be used for filling the container12. It may be a simple open port that can be closed manually when so needed, or alternatively, it can be a port that can be automatically open when a matching delivery structure is inserted. It may also even be designed such that the delivery structure opens and seals the connection between the two ports. In another exemplary construction, the delivery structure may actually be the bottom of the container12. This would allow stacking of the containers one on top of the other, where each upper container12could automatically fill the lower ones when so stacked. Sensors, e.g., an optical sensor disposed at the output port of the container12, could be utilized to indicate an “empty status” of each container. Alternatively, the frequency response of the sonic/ultrasonic vibrators could be used to determine the empty status of the container12.

The containers12would be filled at a central bulk material source location. They would then be delivered to the well site using conventional delivery means. Forklifts are the preferred method for moving the containers12around the plant and well site given their pervasive use in other well operations. It should be further noted, as those of ordinary skill in the art will appreciate, that while the containers12are primarily designed for delivering sand, proppant, and possibly additives used in the fracturing process, it is also suitable for cement transport as well and other applications.

As noted above, the containers may be implemented into the existing Mountain Mover® storage system. One way in which they may be implemented into such a system is by extending the volume of the each compartment of the Mountain Mover® storage system. To do this, the walls do not have to have any bottom (such as would otherwise be necessary to accommodate the folks of a forklift, as would be the case in the use of individual containers) so as the top structure is lifted, it is open to the lower part of the compartment. Furthermore, the lower conical structure feature would also not be necessary in such an application. Furthermore, a matching container can be stacked on it to further enhance its capacity.

With further reference toFIG. 2, additional details of the collapsible container12will now be described. The container12includes a collapsible frame. The collapsible frame includes a rigid upper support structure40and a rigid lower support structure42. The upper support structure or frame40may take many different forms or configurations. In one exemplary embodiment, the upper support structure40is formed by connecting four bars or beams into a rectangular configuration. In one exemplary embodiment, the rectangular configuration is a square. Additional beams or other support structures may be provided to further strengthen the upper support structure40. The cross-beams may be formed of any number of materials. Some exemplary materials include a metal alloy or composite material. Any other suitable rigid material may be utilized as those of ordinary skill in the art will recognize. The lower support structure or frame42may be formed in the same configuration and of the same materials as that of the upper support structure40.

The collapsible frame further includes one or more support members44coupled at one end to the upper support structure40and coupled at another end to the lower support structure42. The one or more support members may in one exemplary embodiment be a rod or bar which is fixed but pivots at one end located, for example, at the upper support structure40and which is restrained vertically at the other end, for example, at the lower support structure42. In one exemplary embodiment, the support members44are allowed to slide horizontally along the lower support structure42. They slide along one or more tracks46. By sliding along tracks46the support members44enable the upper support structure40to expand and collapsible relative to the lower support structure42much like an accordion. In one exemplary embodiment, there are two support members44disposed on one side of the container12, as illustrated inFIG. 2. There may also be two additional support members45on an opposite side of the container12, as shown inFIG. 3. The dashed lines illustrate the support members44in their fully vertical orientation wherein the container12is at its full storage capacity configuration. The solid lines show the support members transitioning either between the expanded position to the collapsed position or vice versa. Alternatively, the container12may assume a partially collapsed configuration so that multiple containers containing bulk material can be stacked on the bed of a trailer, even though full of material to save space. The flexible nature of the material containment portion of the container as discussed below further enables this configuration.

Actuators48aand48bare coupled to the support members44at the ends secured within the tracks46. By activation of the actuators48aand48b, the support members44move along the tracks46and thereby raise and lower, i.e., expand and collapse the upper support structure40relative to the lower support structure42. One or more devices may be used as the actuators. They may be pneumatic cylinders, hydraulic cylinders, manually-operated cylinders, cylinders operated by an electric motor, linear actuators, ball cylinders or any combination thereof. Furthermore, the support structures45on the other side of the container may be connected to the support members44via cross-bars56, as shown inFIG. 3. This enables the support members45to be activated by the actuators48aand48bthus obviating the need for a second pair of actuators48on the other side of the container12.

The collapsible container12further includes a containment portion, which in one exemplary embodiment is a storage sack50. The storage sack50is defined by an upper portion52coupled to the upper support structure40and a lower portion54coupled to the lower support structure42. The upper portion52of the storage sack50may be formed of a plurality of attached rigid or semi-rigid panels, e.g., panels58a-d, as shown inFIG. 4. The lower portion54of the storage sack50may be generally taper-shaped and formed of a generally flexible material60. As noted above, the lower portion54may be conical in shape. In one exemplary embodiment, it is a 20-30 degree square cone. Having a generally taper or conical shape allows for better downward flow of the particulate matter.

In one exemplary embodiment, the storage sack50is formed of one of the following materials: a cloth, a canvas, a canvas coated with a rubber material, a canvas coated with an elastomeric material, a woven nylon, woven polyethylene, a plastic, a woven glass coated with a rubber material, a woven glass coated with an elastomeric material, a gunny sack and any combination thereof. The storage sack50has an interior which may also be formed of a plurality of connected tension panels62, as shown inFIG. 4.

The container12may further include a pair of tubes64aand64bformed along opposite sides of the lower support frame42, as shown inFIG. 2. In one exemplary embodiment, the pair of tubes64aand64bare formed as part of (i.e., integrated into) the lower support structure42. The pair of tubes preferably has a generally rectangular cross-section, so as to be able to accommodate the forks of a forklift.

The container12further includes a discharge opening66formed in the lower portion54of the storage sack, as shown inFIG. 4. In one exemplary embodiment, the discharge opening66is equipped with a valve68, which can control the flow rate of the material being discharged out of the container12. Other material control devices may be used in place of the valve. Some other non-limiting examples include a swing gate, pinch gate, annular pinch valve, butterfly valve and combinations thereof. The container12may further include a rope70to couple or attach the lower portion54of the storage sack50to the lower support structure42. Alternatively, a panel or other similar structure may be used to attach the lower portion54of the storage sack50to the lower support structure42. The upper portion52of the storage sack50being semi-rigid may be attached to the upper support structure40by bolts, rivets, or other similar known securing means.

The container12may further include a sonic or ultrasonic vibrator72coupled to the lower portion54of the of the storage sack50to aid in the dispensing of the bulk material out of the container12. As noted above, by monitoring the frequency of the storage sack50's response to the vibration produced by the vibrator72, the empty status of the container12may be monitored.

A portable bulk storage system32may be provided at the well site for storing one or more additional containers12of bulk material to be positioned on the frame16of the support structure14, as shown inFIG. 1. The bulk material containers12may be transported to the desired location on a transportation unit (e.g., truck). The bulk storage system32may be the transportation unit itself or may be a skid, a pallet, or some other holding area. One or more containers12of bulk material may be transferred from the storage system32onto the support structure14, as indicated by arrow34. This transfer may be performed by lifting the container12via a hoisting mechanism, such as a forklift, a crane, or a specially designed container management device. In this embodiment, the containers12are stacked, one on top of another, as shown inFIG. 1.

When the one or more containers12are positioned on the support structure14, discharge gates on one or more of the containers12may be opened, allowing bulk material to flow from the containers12into the outlet18of the support structure14. The outlet18may then route the flow of bulk material directly into a blender inlet (e.g., into the hopper22or mixer24) of the blender unit20.

After one or more of the containers12on the support structure14are emptied, the empty container(s)12may be removed from the support structure14via a hoisting mechanism. In some embodiments, the one or more empty containers12may be positioned on another bulk storage system32(e.g., a transportation unit, a skid, a pallet, or some other holding area) until they can be removed from the site and/or refilled. In other embodiments, the one or more empty containers12may be positioned directly onto a transportation unit for transporting the empty containers12away from the site. It should be noted that the same transportation unit used to provide one or more filled containers12to the location may then be utilized to remove one or more empty containers12from the site. One of the advantages of the collapsible nature of the containers12in accordance with the present invention is that many more empty containers12can be removed from the well site than was previously possible given the compact space that the containers12occupy in their collapsed state.

The embodiment shown inFIG. 5illustrates an embodiment wherein the collapsible containers12in accordance with present disclosure are incorporated into the bins of a large transportation unit such as the Halliburton Mountain Mover® trailer system discussed above. The bulk storage system in accordance with this embodiment is referenced generally by numeral100. The system100includes transportation unit102, which may be a trailer, which can be connected to tractor or one-piece truck. The transportation unit102has a plurality of collapsible containers12disposed on the unit in a stacked configuration. The collapsible containers12may have the structure described with reference toFIGS. 2-4. The plurality of collapsible containers12may be arranged so as to form the bins or silos of the Mountain Mover® trailer system. The discharge openings of the bottom row of collapsible containers12empty the bulk material contents onto a conveyor104, which in turn may deliver the bulk material to the blender unit20.