Bottom dump pneumatic material handling system

A material (e.g., proppant) handling system includes a storage container, a mechanical conveyor system, and a pneumatic conveyor system. The mechanical conveyor system is configured to convey material from an unloading station to a conveyor system discharge and into an inlet of the storage container (e.g., at an elevation that is higher than the unloading station). The pneumatic delivery system is configured to deliver material from the storage container to an off-system destination (e.g., a silo or the like), pneumatically. In a typical implementation, the storage container, the mechanical conveyor system, and the pneumatic conveyor system are all on, or connected to, or supported by one common chassis.

FIELD OF THE INVENTION

This application relates to a handling system for bulk powder or granular material, such as proppant, and methods of utilizing the proppant handling system and, more specifically, relates to a proppant handling system configured to receive a bottom dump (or gravity fed) proppant delivery and to convey that proppant delivery, pneumatically, to an off-system destination (e.g., a silo or the like).

BACKGROUND

Hydraulic fracturing (or fracking) refers to a well stimulation technique that involves injecting high-pressure fracking fluid into a wellbore to create cracks in deep-rock formations through which petroleum resources, such as oil or natural gas, can flow. Fracking fluid may vary in composition depending on a variety of considerations and the specific application to which the fracking fluid is to be applied. Typically, however, fracking fluid contains sand or some other proppant that is designed to keep any fractures produced by the fracking process open during and after the fracking process.

Proppant (e.g., sand or the like) typically is delivered to a work site (e.g., a hydraulic fracturing well head), stored temporarily at the work site in one or more silos or other types of storage containers, then, at an appropriate time, blended together with other components of the fracking fluid to form the end product to be injected into the wellbore.

A variety of other industries exist that involve handling bulk powder or granular material.

SUMMARY OF THE INVENTION

In one aspect, a handling system for bulk powder or granular material (e.g., proppant) includes a storage container, a mechanical conveyor system, and a pneumatic conveyor system. The mechanical conveyor system is configured to convey proppant from a proppant unloading station to a conveyor system discharge that unloads into a storage container that may have an inlet that is at a higher-elevation than the proppant unloading station. The pneumatic delivery system is configured to deliver proppant from the storage container to an off-system destination (e.g., a silo or the like), pneumatically. In a typical implementation, the storage container, the mechanical conveyor system, and the pneumatic conveyor system are all on, or connected to or supported by, a common portable chassis (e.g., a trailer chassis, skid, framework, base, etc.).

In another aspect, a method is disclosed for using the handling system at a worksite (e.g., near a wellhead for a hydraulic fracking operation, where there are silos or other types of onsite proppant storage containers). The method includes providing the handling system at the worksite, receiving a delivery of material (e.g., proppant) at the handling system, conveying the material in the system to the system's storage container, and utilizing the system's pneumatic conveying system to convey the material from the storage container to an off-system destination (e.g., an onsite silo or the like).

In some implementations, one or more of the following advantages are present.

For example, in some implementations, the handling system described herein provides a simple, elegant solution for conveying material (e.g., proppant) that has been delivered to a worksite via a gravity feed trailer or other container, into a silo or other onsite container, pneumatically. In this regard, many dry bulk products can be transported economically in bottom dump or end dump containers (or even in pneumatic trailers that have bottom dump capabilities) where they are unloaded via gravity flow out the lowest point of the container. At the destination it may be desirable to move the product pneumatically, into a silo or the like, to suit existing work methods and physical facilities. In various implementations, the systems and techniques disclosed herein can help facilitate achieving that goal.

Moreover, in a typical implementation, the handling system described herein can provide fairly significant advantages if it is available at a worksite (e.g., near a hydraulic fracturing wellhead site with silos and/or other onsite proppant storage containers). More specifically, having the handling system available at such a worksite would make that worksite very well suited to receive a delivery of material (e.g., proppant) from virtually any kind of conventional proppant delivery vehicle or container. If, for example, a proppant delivery arrived via a pneumatic trailer, then the proppant could simply be conveyed directly from the pneumatic trailer into any one or more of the silos or other storage containers (bypassing system100) by using the trailer's own pneumatic delivery system. Alternatively, if the pneumatic trailer also has bottom dump capabilities, them the pneumatic trailer could be used to deliver proppant via bottom dump into the handling system. In many instances, unloading via bottom dump in reliance on gravity may be faster, and energy efficient, than unloading in reliance on the trailer's built-in pneumatic conveying system.

If, however, a proppant delivery arrived via a gravity feed trailer (positioned over the proppant unloading station102), then the proppant could be gravity fed into the proppant handling system and the proppant handling system can be used to convey the proppant into the silo or other off-system storage container with pneumatic power.

Likewise, if the proppant delivery arrived in a proppant delivery container, such as a container made by the SandBox Logistics™ company, then the proppant delivery container can be placed atop the proppant handling system (e.g., supported by a cradle or container unloader kit, described herein), emptied into the proppant handling system (via gravity), and the proppant handling system can be used to convey the proppant into the silo or other off-system storage container with pneumatic conveyance.

In some implementation, the delivery system described herein has some built-in redundancies that can provide a hedge against the possibility of certain system components failing, but that also can be used to throttle the system's proppant delivery rate up or down.

Moreover, in various implementations, the storage container between the truck unloading conveyor and pneumatic system provides more than just a convenient transition between one conveyor (i.e., a mechanical one) and a second conveyor (i.e., a pneumatic one). For instance, in some implementations, the storage container can provide a buffer between disparate conveying rates between the mechanical conveyor system (which may include one or more belt conveyors) and the pneumatic system. Pneumatic systems tend to be slower than mechanical conveying systems and so establishing a good transfer rate and operating it at steady-state may be desirable rather than taking the slower system and then adding inefficiency by sporadic flow of product. Moreover, the storage container may allow movement of trucks between separate storage hoppers or different trucks without running the pneumatic system out of product. By its nature, unloading the trucks creates uneven flow—start/stop, move truck to next hopper, switch trucks etc. so there may be lots of non-productive time in terms of unloading. The storage container allows for a fast belt conveyor that creates a buffer of product to allow the pneumatics to operate continuously (or more continuously than the mechanical conveyor), often at a steady, optimal rate. Moreover, the storage container may allow more trucks to be unloaded, via gravity, more quickly than pneumatics would do alone.

Other features and advantages will be apparent from the description and drawings, and from the claims.

Like reference characters refer to like elements.

DETAILED DESCRIPTION

There are a variety of ways that material (e.g., proppant) can be delivered to a worksite (e.g., a wellhead in the hydraulic fracturing (fracking) industry).

One way of delivering proppant to a worksite uses pneumatic trailers that have built-in provisions for pneumatically unloading the proppant directly into an onsite silo. If proppant is delivered to a worksite using a pneumatic trailer, then the proppant usually can be off-loaded easily using the trailer's own pneumatic conveying system. The pneumatic system on the trailer, however, can be complex, costly, heavy and take up a lot of valuable space on the trailer that otherwise might be used to carry more proppant. Moreover, pneumatic conveyance can, in some instances, be slower than bottom dump gravity conveyance.

Another way of delivering proppant to a worksite uses gravity feed trailers that simply drop the proppant out of one or more openings in the bottom of the trailer under the influence of gravity. This is a relatively simple approach for delivering proppant to a worksite, and one that tends to maximize the proppant-carrying capacity of the trailer. These trailers also tend to be less expensive than pneumatic trailers and also unload faster and more efficiently than pneumatic trailers. However, if the proppant is simply dropped out of the bottom of the trailer, the worksite may need various material handling equipment to move the proppant up and into its onsite storage silos. This added equipment can be complex, costly, difficult to obtain where needed, particularly in a timely manner, and can require onsite expertise to assemble/operate.

Some pneumatic trailers also have the ability to deliver material via gravity through a hoppered opening via bottom dump in addition to pneumatic conveying capabilities.

Yet another way of delivering proppant to a worksite uses discrete proppant delivery containers, such as the type of containers available from the SandBox Logistics™ company that are able to be lifted off a delivery trailer with a forklift, for example, and placed, full of proppant, onsite for temporary storage. These types of containers can be loaded by forklift onto a cradle or container unloader kit that enables the proppant to be gravity fed from the container into a blender hopper, for example. Using these kinds of proppant delivery containers provides for a relatively simple way of delivering proppant to a worksite. However, storing the proppant delivery containers onsite requires extra storage space onsite. Moreover, various material handling equipment may be needed at the worksite to facilitate delivering proppant from the container into the blender hopper and/or into a silo. This added equipment can be complex, costly, difficult to obtain where needed, particularly in a timely manner, and can require onsite expertise to assemble/operate.

FIGS. 1-8show an example of a material handling system1100that can be used at a worksite to conveniently transfer proppant, for example, from a gravity feed source (e.g., a trailer, proppant delivery container, etc., not shown inFIGS. 1-8) into a silo or other storage container onsite (also not shown inFIGS. 1-8), pneumatically.

If the illustrated system1100is available at a particular worksite that has one or more silos, then proppant can be easily conveyed into any of those silos, pneumatically, regardless of how the proppant was delivered to the worksite (i.e., whether the delivery was by pneumatic trailer, by gravity feed trailer, by one of the proppant delivery containers mentioned above, or by some other means). Moreover, the material handling system1100is portable and, therefore, can be moved around a worksite, or from worksite-to-worksite, with relative ease to deliver the proppant into silos. Of course, this portability makes the material handling system1100easy to stow away when not being used as well. The system1100also is relatively simple in design and operation.

At the outset, it should be made clear thatFIGS. 1-8show only one example of how certain aspects of the invention(s) disclosed herein may be implemented. Numerous variations are possible. Indeed, each individual component of the system1100shown inFIGS. 1-8could be replaced with a different component(s) that performs substantially similarly as the component shown without departing from the spirit and scope of the invention(s). The arrangement of components also can be varied without departing the spirit and scope of the invention(s). This idea is reiterated and expanded upon throughout the specification.

The illustrated system1100has a chassis1101supported on wheels1105. The front end of the chassis1101can be connected to a truck or other vehicle for hauling around as desired or needed. All other system components shown in the illustrated implementation are mounted, either directly or indirectly, onto and, therefore, supported by the chassis1101.

The illustrated system1100has a proppant unloading station1102, a mechanical conveying system1104, a proppant holding container1106, and a pneumatic conveying system1108. The proppant unloading station1102is configured so that a bottom dump trailed can be driven over the proppant unloading station1102and delivery proppant (e.g., via gravity drop) into the proppant unloading station1102. The mechanical conveying system1104utilizes mechanical components (e.g., a conveyor belt assembly) to convey the proppant from the proppant unloading station1102up and into an opening at or near the top of the proppant holding container1106. Belts are absent inFIG. 2, for example, but would follow the angled upward track defined by the belt supports shown. The pneumatic conveying system1108uses pneumatic pressure to convey proppant that is released from the bottom of the proppant holding container1106to a discharge1109near a rear of the system1100. In a typical implementation, a hose or pipe can be attached to the discharge1109of the pneumatic conveying system1108to carry the discharged proppant to an on-site storage container, such as a silo or the like. An air lock1124(or functionally similar structure(s)) is provided to allow the proppant to move from the proppant holding container1106into the pneumatic conveying system1108, without compromising the pressure differential between the proppant holding container1106and the pneumatic conveying system1108.

The chassis1101in the illustrated system1100is a rigid structure and includes high strength, typically metallic, beams that may be welded together to form a structure or frame to support various other system components, as shown. The chassis1101is coupled to, and supported by, the wheels1105and typically includes provisions for hitching the chassis1101to a hauling vehicle. In a typical implementation, t one or more rigid plates are provided to form platforms or walls that may be mounted to and supported by the frame structure of the chassis1100as well.

The chassis1100supports a drive-over ramp assembly1130. The drive-over ramp assembly1130includes four ramp panels1131—two on each lateral side of the chassis1100. Each ramp panel1131is supported at a proximal end by a hinged connection1133along an upper lateral side edge of the chassis1101that enables the ramp panel1131to move, about the hinged connection1133, between the deployed position (shown inFIG. 1-4) and a stowed (or transport) position (shown inFIGS. 5-8). In the stowed (or transport) position (shown inFIGS. 5-8), the ramp panels1131extend in a substantially upward (and slightly inward) direction. In the deployed position (shown inFIGS. 1-4), the ramp panels1131extend laterally outward and downward so that their distal ends rest on the ground, thereby forming a ramp, over which a proppant delivery vehicle can drive.

In the illustrated implementation, hydraulic rams1135provide the energy to move the ramp panels1131between the deployed position and the stowed position. Each ramp panel1131has two hydraulic rams1135—one at a forward end of the ramp panel1131and one at a rear end of the ramp panel1131. Each hydraulic ram1135has a first end that is secured to and supported by a portion of the chassis that remains stationary as the associated ramp panel1131moves up or down, and a second end that is secured to the ramp panel1131itself. In the illustrated implementation, the hydraulic rams1135extend to raise the ramp panels1131and retract to lower the ramp panels1131.

The ramp panels1131are configured to facilitate a proppant delivery vehicle driving over them to position its bottom dump opening above the proppant unloading station1102. More specifically, there is a forward-most ramp panel and a rear-most ramp panel on each side of the chassis. In the deployed position (FIGS. 1-4), the forward-most ramp panel on the left side of the chassis aligns with the forward-most ramp panel on the right side of the chassis, and the rear-most ramp panel on the left side of the chassis aligns with the rear-most ramp panel on the right side of the chassis. Moreover, the forward-most ramp panel on each respective side of the chassis is sufficiently displaced from the rear-most ramp panel on that side of the chassis such that a proppant delivery vehicle (e.g., a delivery truck with bottom dump capabilities) attempting to drive over the ramp panels will have its right side wheels supported by either the forward-most ramp panels or the rear-most ramp panels, and will have its left side wheels supported by the other of the forward-most ramp panels or the rear-most ramp panels.

Panels extend across the top of the chassis1101to support the wheels of a proppant delivery vehicle driving over them. These panels, together with the ramp panels1131, collectively define two tracks to support the wheels of a proppant delivery vehicle driving over the proppant unloading station1102. The chassis and panels supported by the chassis near the proppant unloading station1102define an upward-facing aperture (or opening)1137, covered by a grating1139, between the two tracks. The aperture1137is above part of the mechanical conveying system1104. More specifically, the aperture1137in the illustrated implementation is above a moving conveyor belt of the mechanical conveying system1104. As such, if a proppant delivery vehicle drives over the ramp assembly and bottom dumps a delivery of proppant into the aperture1137and through the grading1139, the moving conveyor belt can immediately convey the proppant, as it is being unloaded, in a rearward direction away from just under the grating1137. In a typical implementation, the grating helps prevent large objects (e.g., non-proppant from falling into the mechanical conveying system1104.

The mechanical conveying system1104moves the unloaded proppant away from the proppant unloading station1102and to an opening in or near the top of the proppant holding container1106. There are a variety of ways that the mechanical conveying system1104can perform this function. In one exemplary implementation, the mechanical conveying system1104has one or more moving conveyor belts that convey the proppant in a rearward, horizontal direction away from the proppant unloading station1102and then in an upwardly angled direction to the opening in or near the top of the proppant holding container1106. In one such implementation, the mechanical conveying system1104has a first section of conveyor belt that extends (and moves proppant) from just under the grating1137in a rearward direction to a second section of conveyor belt that extends (and moves proppant) from the end of the first section in an upwardly-angled direction to the opening in or near the top of the proppant holding container1106.

In some implementations, the conveyor belt(s) may be curved to define a lateral cross-section with a somewhat concave upper surface to discourage proppant from falling off the sides of the conveyor belt as the proppant is being conveyed. In some implementations, other measures, such as providing separate physical barriers on the sides of the conveyor belt(s), may help prevent the proppant being conveyed from falling off the sides of the conveyor belt(s).

The conveyor belt(s) may be supported and/or directed, by pulleys and/or guide elements. The conveyor belt(s) can be powered in any one of a variety ways. In a typical implementation, one or more of the pulleys for the conveyor belt is driven by prime mover, such as an electric or hydraulic motor or the like.

The upward angle of the upwardly-angled portion of the conveyor belt will depend on the specific geometry of the system1100. In some implementations, however, the upward angle is between about 10 to 45 degrees (or more preferably between about 20 to 30 degrees) from the longitudinal axis of the chassis1101. In one exemplary implementation, the upward angle is 28 degrees.

The mechanical conveying system1104has a housing1116that covers significant portions of the mechanical conveying system1104. This housing1116helps prevent contamination from getting into the system1100and potentially contaminating the proppant, and also helps contain any dust that may be generated by the proppant being conveyed in the mechanical conveying system1104. The illustrated system1100also has a dust collector1118coupled to the housing1116of the mechanical conveyor system1104to help collect dust that is generated from the proppant being conveyed in the mechanical conveying system1104.

The dust collector1118can perform its function in any one of a variety of ways. In some implementations, the dust collector1118may be a closed loop dust collection system like the dust collector in the Quickload 300™ transloading system, available from Smart Sand, Inc. In some implementations, the dust collector1118may be similar to any one of the dust collectors described in U.S. Pat. No. 10,301,108, entitled Silo Dust Collection and assigned to Quickthree Technology, LLC, the owner of this application. In some implementations, the dust collector creates a low pressure, or vacuum, inside the housing1116of the mechanical conveying system1104. This low pressure, or vacuum, may help draw proppant into the system1100through the aperture at the proppant unloading station1102, thereby helping to contain the escape of dust from the system at the point of unloading.

At the end of the mechanical conveying system1104, proppant is dropped into an opening at or near the top of the proppant holding container1106. In a typical implementation, the housing1116of the mechanical conveying system1104seals against the outer surface of the proppant holding container1106to prevent environmental contamination from entering the system1100and to prevent proppant dust from escaping to the environment.

The proppant holding container1106is a large, hollow, rigid container. In one implementation, the proppant holding container1106has a storage capacity of approximately 43 tons. In another implementation, the proppant holding container1106has a storage capacity of approximately 40 tons. The proppant holding container1106has a lower surface that forms a hopper1120with a discharge opening (or outlet)1122at its bottom. In some implementations, the discharge opening1122at the bottom of the hopper1120is gated or otherwise controllable (e.g., with a valve or the like) to regulate the flow of proppant out of the proppant holding container1106.

The pneumatic conveying system1108has multiple air blower assemblies1126, each of which is configured to provide pressurized air inside the pneumatic conveying system1108for conveying proppant that has been released from the proppant holding container1106to the system discharge1109and beyond. Each air blower assembly1126has an intake air filter1141, which is connected in series to an intake silencer1143, which is connected in series to a blower1145, which is connected in series to an outlet silencer1147. The blowers1145are driven by prime movers, which, in the illustrated implementation, are electric motors. More specifically, the pneumatic conveying system1108in the illustrated implementation has three such air blower assemblies1126.

In each air blower assembly1126, the blower1145draws air into the system from the environment through the air filter1141and the air intake silencer1143. The air filter1141filters the air entering the system1100to help ensure that the air passing into and through the blower1145and the system1100will be relatively free of contaminants.

The intake air silencer1143in each blower assembly1126helps reduce any air borne noise produced by the blower1145. If the blower1145is a rotary positive displacement blower, for example, as the blower's impeller rotates, air is sucked into the blower, drawing slugs of air into the system1100at a frequency that depends on the speed and number of lobes in the impellor. The intake air silencer1143in this instance may serve to smooth out these slugs of air and reduce the noise emanating from the blower inlet.

The blower1145in each blower assembly1126can be virtually any kind of mechanical component that can move air. In a typical implementation, the blower1145is a positive-displacement blower, such as a rotary blower or a reciprocating blower. A rotary-type blower may use internal gears, screws, shuttle blocks, flexible vanes or sliding vanes, circumferential pistons, flexible impellers, helical twisted roots, or liquid-ring pumps, for example, to move the air. A reciprocating-type blower may be a piston pump, plunger pump, or diaphragm pump. Other configurations for the blower1145are possible as well.

The outlet silencer1147in each blower assembly1126can serve to reduce pressure pulses and generally smooth out air flow from the blower. If a blower1145is a rotary positive displacement blower, for example, the blower1145generally discharges air in compressed slugs that can be destructive to equipment downstream of the blower1145. The outlet silencer1147helps reduce these pulsations, and smooth out the resulting air flow.

In various implementations, providing the system1100with multiple air blower assemblies1126, as shown, provides a degree of redundancy in the system1100. Alternatively, in some implementations, more than one of the air blower assemblies1126may be operated together, simultaneously, to increase the conveying capacity of the pneumatic conveying system1108. In a typical implementation, the air blower assemblies1126are connected to the discharge1109(which in the illustrated implementation is the distal open end of a pipe) via a network of pneumatic channels, which may include pipes, hoses, and/or valves, for example.

The discharge1109can be connected to an external proppant delivery channel (not shown), which may be a pipe, tube, hose, etc. that can carry the proppant to a nearby silo, blender hopper, or some other on-site storage or proppant treatment container. Typically, this external proppant delivery channel would be routed to an inlet at or near the top of the silo, blender hopper, or other container. The inlet to the silo, blender hopper, or other container would usually be significantly higher than the discharge1109of the system1100. Thus, the conveying capacity of system1100is high enough to convey the proppant to that higher point.

The proppant holding container1106discharges proppant from the discharge opening1122at the bottom of the hopper1120. The discharged proppant passes through the air lock1124and into the pneumatic conveying system1108. In general, the air lock1124can be any mechanical component or combination of mechanical components that allows proppant to flow out of the proppant holding container1106and into the pneumatic conveying system1108, without compromising or significantly compromising the pressure differential between the proppant holding container1106and the pneumatic conveying system1108.

There are numerous ways to implement the air lock1124. Some of these are discussed below. However, the discussion below is not exhaustive. Other options are possible and fall within the scope of the current disclosure.

In some implementations, the air lock is a rotary-type air lock. Typically, a rotary-type air lock has a housing that defines an inlet, an outlet, and a rotor housing between the inlet and the outlet. The inlet of the air lock would be connected to the discharge opening of the proppant holding container1106and the outlet of the air lock would be connected to the pneumatic conveying system1108. The rotor housing houses a centrally-disposed rotor shaft that can rotate and that supports a plurality of rotor vanes that extend radially outward from the rotor shaft. These rotor vanes are usually regularly spaced around a perimeter of the rotor shaft. Each vane is sized so that its distal end will be very close to, or in contact with, the inner surface of the rotor housing. The rotor shaft may be driven by a small engine or motor (e.g., electric, pneumatic, hydraulic, etc.) or any type of rotational drive. During operation, the engine or motor, for example, turns the rotor shaft, which causes the rotor vanes to rotate thereabout. Granular proppant falls, by gravity, into the inlet, and the rotating rotor vanes move the granular proppant in a downward direction into the pneumatic conveying system1108beneath the rotary air lock. At the same time, the close proximity or contact of the vanes to the inner surface of rotor housing help prevent pressurized air from the pneumatic conveying system1108from escaping through the rotary air lock and into the proppant holding container1106. Thus, granular proppant is moved from the lower pressure proppant holding container1106into the higher pressure pneumatic conveying system1108without compromising the pressure differential therebetween.

In some implementations, the air lock is a screw-type air lock. One example of a screw-type air lock is a Meyer pneumatic screw pump, available from the Meyer Industrial Solutions company. A pneumatic screw pump is an airlock that uses a screw auger to move the proppant from a gravity feed hopper into a pneumatic conveying system. A pneumatic screw pump typically utilizes the conveyed material itself (e.g., the proppant) to form a seal between the lower pressure proppant holding container and the higher pressure pneumatic conveying system. In some implementations, the pneumatic screw pump may have a gate valve (e.g., a flap-style gate valve downstream of the screw auger) to help prevent blow-back (e.g., the screw pump is being primed and/or when the screw pump runs on empty).

In some implementations, the air lock may include gate lock valves configured, for example, in a manner described in section 3.5 of thePneumatic Conveying Design Guide, by David Mills, Second Edition. ThePneumatic Conveying Design Guideis hereby incorporated by reference in its entirety herein. An air lock that incorporates gate lock valves typically includes two (or more) gate lock valves that alternately open and close to permit proppant to pass from the proppant holding container to into the pneumatic conveying system. Pressurized air that passes through the lower gate from the pneumatic conveying system may be vented so that it does not interfere with the material about to flow through the upper gate. These gates may be driven in any number of ways including, for example, by motor, cam or air cylinder, or gravity. The gate valves may be virtually any kind of gate valves. One such example is a pneumatic ceramic rotary gate valve, available from Henan Quanshun Flow Control Science & Technology Co., Ltd. Other variations are, of course, possible as well.

In various implementations, the air lock may be configured in any other manner that is disclosed in thePneumatic Conveying Design Guide, including, for example, those described in section 3.2, entitled “Rotary Valves” of thePneumatic Conveying Design Guide.

FIGS. 9-11show an alternative implementation of an air lock1924between a proppant holding container1906and a pneumatic conveying system1908. The illustrated air lock1924has multiple pressure tanks1980, each of which has an upper inlet valve1982and a lower outlet valve1984. The inlet valve1982controls the flow of proppant from the proppant holding container1906into the associated tank1980. The outlet valve1984controls the flow of proppant from the tank1980into a corresponding conveying line of the pneumatic conveying system1908. The system also has air lines1986that can feed pressurized air into the tanks1980.

In various implementations, the air lock1924may have single or multiple valves. One design iteration uses dual inlet and outlet valves. The purpose is that the upper valve in each pair is used to control the flow of proppant and the lower valve in each pair controls air flow. The valves have offset open and close functions so that the valve which seals airflow operates without the flow of sand occurring. This arrangement helps promote lifespan of the critical air-seal function. For example, if you close the upper valve first and stop the flow of proppant and then wait to operate the lower valve until the sand has flowed through it, it can close without cutting through the column of flowing sand. Advantageously, with the use of dual valves, the top valve cuts and stops the flow of sand and the lower valve closes free of sand and thus the seal will last a lot longer.

The illustrated implementation has three conveying lines and six pressure tanks1980. Each pressure tank1980is connected via its inlet valve1982to the proppant holding container1906(e.g., typically to a hoppered outlet at the bottom of the container1906). Moreover, each pressure tank1980is connected via its outlet valve1984to one of the conveying lines. Additionally, each conveying line is connected to two of the pressure tanks. During operation, in a typical implementation, each tank1980draws sand from the proppant holding container through its inlet valve (or gate) which controls the flow of proppant into the tank. Once full, the inlet valve for that gate is closed. Then, the tank may be “topped off” with pressurized air—delivered from an on-system air compressor, for example—to increase the pressure within the tank to the same pressure as the conveying line, or higher. Then, the outlet valve1984for that tank1980is opened to allow the pressurized proppant to flow into the conveying line (and out to a silo, for example). Once the tank1980has been emptied, the outlet valve1984for that tank can be closed. Then, the pressure within the tank1980is vented and the inlet valve1982can be opened again. In this regard, the system may include a vent line from each tank1980to allow the tank to discharge pressure prior to opening the inlet for filling. In some instances, the vent line may be connected to the dust collector

In a typical implementation, the air lock1924may be operated by filling one tank1980that is attached to a particular conveying line, while unloading the other tank1980that is attached to that conveying line. This helps achieve more constant flow of proppant out of the system. One or more than one conveying lines may be operational to convey proppant at any given time. Moreover, the opening and closing of the valves, the introduction of air into the tanks, etc. may be performed automatically by a system controller.

The illustrated system has three conveying lines, with two tanks1980per conveying line. This, however, can be varied considerably. For example, in some implementations, a system might include only one tank1980and one conveying line. In some implementations, a system might include any number of tanks1980with only one conveying line. In some implementations, a system might include only one tank1980per conveying line, but more than one conveying line. Essentially, any combination of tanks and conveying lines may be included in a particular implementation.

Returning toFIGS. 1-8, the system1100shown there also has an electrical generator set1429on a raised platform1421near the front end of the chassis101. The electrical generator set1429may be virtually any set of components (e.g., diesel engine with an electrical generator) configured to produce electrical energy that can be used by one or more of the various components (e.g., lights, blowers, controls, etc.) in the system1100. In some implementations, in fact, the electrical energy produced by the electrical generator set1429may be used to power motor(s) for the air blower(s)1145, motor(s) for the air lock(s), and/or the ramp panels, etc. IN a typical implementation, the system1100includes a fuel tank as well. The fuel tank also may be mounted on the raised platform, near or integrated into the electrical generator set1429. The fuel tank supplies fuel to the internal combustion engines (typically via one or more fuel pumps).

The electrical generator set1429feeds the electrical energy it generates to a power distribution panel1427, which distributes the electrical energy to any electrically-powered components in the system1100.

The system1100also has an operator control panel1425. The operator control panel1425can have any one of a variety of different configurations. However, in a typical implementation, the operator control panel1425would include all of the controls that a system operator would need access to in order to operate the system1100. This might include controls for the electrical generator set1429, controls for the pneumatic conveying system1108(including each air blower1145), controls for the mechanical conveying system1104, controls for the air lock(s)1124), etc.

The system1100has jacks1123attached to the chassis1101and extended in a downward direction. The jacks1123can be retracted so that the system1101can be moved (e.g., hauled by a hauling vehicle). The jacks1123can be extended to lift the system1101, when the system is intended to remain stationary.

In use, the system1100can be hauled with a hauling vehicle to a worksite that includes one or more silos for storing proppant. While being hauled, the system1100rolls behind the hauling vehicle on its wheels1105. Also, while being hauled, the jacks1123are in raised positions and the ramp panels1131are as well (as shown inFIG. 5-8). When the system1100reaches the worksite, the jacks can be extended and the system1100decoupled from its hauling vehicle.

Next, the ramp panels1131can be lowered to the positions shown inFIGS. 1-4. In the lowered position, the ramp panels1131extend in an outward, slightly downward direction so that their distal ends touch the ground.

Next, a bottom dump delivery vehicle drives on the ramp panels to position its bottom dump discharge port above the upward-facing aperture (or opening)1137. The operator turns on the mechanical conveying system1108and opens the bottom dump discharge port over the aperture1137. Proppant begins pouring into the aperture1137, through the grating1139. The proppant is carried by the mechanical conveying system1104into the proppant holding container1106.

A hose, or the like, is attached to the discharge1109of the pneumatic conveying system1108and routed into one of the on-site silos. The pneumatic conveying system1108and the air lock(s)1124are started. Then, the proppant is released (e.g., by opening a valve) from the proppant holding container1106. The proppant passes through the air lock and into a conveying line of the pneumatic conveying system1108, which carries the proppant through the conveying line, then through the hose to the on-site silo.

FIGS. 12-14show another example of a material handling system100that can be used at a worksite to conveniently transfer proppant, for example, from a gravity feed source (e.g., a trailer, proppant delivery container, etc.) into a silo or other storage container onsite, pneumatically.

If the illustrated system100is available at a particular worksite that has one or more silos, then proppant can be easily conveyed into any of those silos, pneumatically, regardless of how the proppant was delivered to the worksite (i.e., whether the delivery was by pneumatic trailer, by gravity feed trailer, by one of the proppant delivery containers mentioned above, or by some other means). Moreover, the material handling system100is portable and, therefore, can be moved around the worksite with relative ease to deliver the proppant into any one of the one or more silos. Of course, this portability makes the material handling system100easy to stow away as well.

Like the system1100inFIGS. 1-8, the system100inFIGS. 12-14is relatively simple in design and operation and highly portable.

In the illustrated implementation, the system100has a chassis101on wheels105. The chassis101can be connected to a truck or other vehicle for hauling around as desired or needed. All other system components shown in the illustrated implementation are mounted, either directly or indirectly, onto and, therefore, supported by the chassis101.

The illustrated system100has two proppant unloading stations102, two mechanical conveying systems104, a proppant holding container106, and a pneumatic conveying system108.

Each proppant unloading station102is configured to receive proppant from above (e.g., via gravity drop from a bottom dump trailer or container positioned above the proppant unloading station102). Each proppant unloading station102includes a portion of one of the mechanical conveying systems104that is exposed from above so that when a proppant delivery vehicle, for example, is positioned above the proppant unloading station102, the proppant delivery vehicle can bottom dump proppant onto the mechanical conveying system104for mechanical conveying.

Each mechanical conveying system104is configured to convey proppant from an associated one of the proppant unloading stations102to an opening in the proppant holding container106. The pneumatic conveying system108is configured to pneumatically convey proppant from the proppant holding container106to one or more off-system destinations (e.g., a silo, blender hopper, etc.).

The chassis101in system100is a rigid structure made up of high strength, typically metallic, beams that may be welded together to form a structure or frame to support various other system components, as shown. The chassis101is coupled to wheels105and typically includes provisions for hitching the chassis101to hauling vehicle. In some implementations, the chassis101may have one or more rigid plates mounted on the frame structure as well. The chassis101in the illustrated implementation defines an opening or space, through which the proppant can be dropped from a delivery vehicle or container into the system100at the proppant unloading station102.

Each mechanical conveying system104, in the illustrated implementation, has a first powered belt conveyor110and a second powered belt conveyor112. Each powered belt conveyor110,112has a pair of pulleys and a belt coupled to the pulleys. In a typical implementation, the pulleys may be driven by prime movers, such as electric motors, etc. In some implementations, there is a single, continuous belt conveyor that has both a lower horizontal and upper angled portion.

Each first powered belt conveyor110extends from the proppant unloading station102, in a rearward, substantially horizontal direction to a second powered belt conveyor112. Each second powered belt conveyor112is very close to an end of its corresponding first powered belt conveyor110and configured such that proppant that is carried by the first powered belt conveyor110will be passed along to or dropped onto the second powered belt conveyor112. In some implementations, the second powered belt conveyor could be a conveyor with a bend in it so that it has one horizontal section which transitions into a sloped/elevated section. Each second powered belt conveyor112extends away from the first powered belt conveyor110in a rearward, upwardly angled direction to a conveyor system discharge114that discharges, according to the illustrated implementation, into the top of the proppant holding container106.

The specific upward angle of each second powered belt conveyor112will depend on the specific geometry of the system100. In some implementations, however, the upward angle may be between about 10 to 45 degrees (or more preferably between about 20 to 30 degrees) from the longitudinal axis of the chassis101. In one exemplary implementation, the upward angle is 28 degrees.

Each mechanical conveying system104has a housing116(that may be built-in) that covers portions of the first powered belt conveyor110and that covers the second powered belt conveyor112. This housing116helps contain any dust that may be generated by proppant moving along on the conveyor belts of the mechanical conveying system104. There is an opening in the housing116above the first powered belt conveyor110at the proppant unloading station102. It is through this opening that the proppant can be delivered into the system100.

Each mechanical conveying system104has a dust collector118that is coupled to (and that may be built-into) the housing116of the mechanical conveyor system104. The dust collector118is generally configured to draw air and dust out of housing116for the mechanical conveyor system104, via vacuum. The dust collector118may be a closed loop dust collection system like the dust collector in the Quickload 300™ transloading system, available from the Smart Sand, Inc. company.

In some implementations, each dust collector creates a low pressure, or vacuum, in the housing116of its mechanical conveying system104. In some implementations, this low pressure, or vacuum, may help draw proppant into the system100at the corresponding proppant unloading station102.

The upper end of the housing116, in the exemplary implementation shown inFIG. 12, bends slightly downward and extends into the top of the proppant holding container106. The second powered belt conveyor112ends near this point so that the proppant carried up the second powered belt conveyor112will fall off the end of the second powered belt conveyor112and into the proppant holding container106.

The proppant holding container106is a large, hollow, rigid container. In one implementation, the proppant holding container106has a storage capacity of approximately 43 tons. The proppant holding container106has a lower surface that forms a plurality of hoppers120(e.g., three), each of which has a corresponding discharge opening (or outlet)122at its bottom. The specific implementation shown inFIG. 12has four hoppers formed in the bottom of the proppant holding container106, and the hoppers are aligned with one another front-to-back. In some implementations, the discharge opening122at the bottom of each hopper120may be gated or otherwise controllable to regulate the flow of proppant out of the proppant holding container106.

The discharge opening122at the bottom of each hopper120is connected to an air lock124. Each air lock includes one or more mechanical components configured to allow the movement of proppant from the proppant holding container106into the pneumatic conveying system108, without compromising the pressure differential between the proppant holding container106and the pneumatic conveying system108. The air locks124can be or include virtually any kind of mechanical component or combination of mechanical components that can perform the foregoing air lock functionalities. For example, the air locks124can be screw-type air lock, rotary air locks of the kind that are used for discharging solid material from hoppers, bins, etc. into pressure or vacuum-driven pneumatic conveying systems.

During operation, proppant flows out of the proppant holding container106, through one or more of the air locks124, and into one or more proppant conveying channels (not shown inFIG. 12) of the pneumatic conveying system108.

The pneumatic conveying system108has three air blowers126that are configured to blow air into one or more proppant conveying channels. In some implementations, the pneumatic conveying system108has a system of valves that facilitate connecting the various air blowers126to various proppant conveying channels. Each proppant conveying channel has a system output that can be connected to an external proppant delivery pipe or tube (not shown). In a typical implementation, the external proppant delivery pipe or tube may be routed to an off-system silo, a blender hopper, or other container.

The air blowers126are driven by prime movers. The prime movers can be internal combustion engines, electric motors, etc. In one exemplary implementation, each air blower126has a capacity between about 800 and 1180 cubic-feet per minute and is driven by a 100-horsepower diesel engine. In an exemplary implementation, the system1100may be configured to deliver 0.5-0.6 tons per minute with three air blowers and three airlocks. In some implementations, the air blowers126may be driven by electric motors powered by an electrical generator set, which may be supported on the chassis (e.g., on a front trailer gooseneck). There is a fuel tank128mounted on a raised section of the chassis101near the forward end of the chassis101. The fuel tank128is configured to supply fuel to the internal combustion engines that drive the air blowers126. In some implementations, the fuel tank128may be configured to provide fuel to operate an electrical generator (not shown) and/or one or more engines to drive the air lock(s) and/or other components of the system100.

The system100has a drive-over ramp assembly130. The drive-over ramp assembly130has a pair of ramp panels131. Each ramp panel131extends from a hinged connection along a lateral edge of the chassis101. The ramp panels131are movable, about its hinged connection, between a stowed (or transport) position (shown inFIG. 12) and a deployed position (shown inFIG. 13). In the stowed (or transport) position (shown inFIG. 12), the ramp panels131extend in a substantially upward direction. In the deployed position (shown inFIG. 13), the ramp panels131extend laterally outward and downward so that their distal edges rest on the ground, thereby forming a ramp, over which a proppant delivery vehicle (see, e.g.,FIG. 13) can drive. When the proppant delivery vehicle (with one or more bottom delivery chutes, shown inFIG. 13) has driven onto the ramp, the bottom delivery chute(s) of the proppant delivery vehicle can be aligned with (and positioned directly above) the proppant unloading station(s)102. In some implementations, the ramp panels131are moved by one or more electrical motors and/or hydraulically (or otherwise).

In some implementations, the ramps (ramp panels) could be made as separate units which get placed in position (as shown inFIGS. 1-4, for example) at the worksite via a forklift, for example. The ramps do not necessarily need to be part of single physical unit with the rest of the system components.

In some implementations, the system100may include a rigid framework (not shown inFIGS. 12-14) supported by, or integrated into, the chassis101that is configured to receive and support a proppant delivery container, such as those available from SandBox Logistics™ or the like above the proppant unloading station(s)102. This framework may be provided instead of, or in addition to, the drive over ramp assembly130. In implementations that include this kind of framework, the proppant delivery container may arrive at the worksite on a delivery trailer, lifted off of the trailer with a forklift, for example, and then placed directly onto the framework for gravity unloading directly into the system100. Once emptied, the proppant delivery container may be lifted, again by forklift, and put onto a truck to be taken away, or placed somewhere else for temporary storage until it is ready to be hauled away.

The system100shown inFIGS. 12-14is supported on the ground by wheels in the rear and by a separate support element132in the front.

FIG. 13is a partial, schematic front view of the system100inFIG. 12showing the ramp panels131of the drive over ramp assembly130in a deployed configuration, and a proppant delivery vehicle234positioned atop the drive over ramp assembly130.FIG. 13shows that the two proppant unloading stations102are located on opposite lateral side of the chassis101.

In the deployed configuration, the ramps of the drive over ramp assembly130extend in a laterally outward and slightly downward direction from the chassis101. The distal edge of each ramp is in contact with the ground upon which the system100is located. Thus, it can be seen that the drive over ramp assembly130, when deployed, forms a ramp that a proppant delivery vehicle (e.g.,234) can drive up from one side (to the position shown inFIG. 13) and down on the other side.

The exemplary proppant delivery vehicle234inFIG. 13has a proppant storage container236with a bottom surface having two hopper sections238, each of which has a discharge opening240at its bottom. With the proppant delivery vehicle234positioned atop the drive-over ramp assembly130, as shown, each discharge240aligns with one of the proppant unloading stations102.

In one exemplary implementation, each engine-blower air lock unit will convey about 0.6 of a ton/minute. So, 4 can convey up to 2.4 tons/minute for the entire unit. Moreover, in an exemplary implementation, the design consists of 53 ft. trailer with a drive over 48 inch (or 36 inch) wide belt conveyor with fold out drive over ramps, an approximately 43 ton storage hopper, a conveyor unload rate into the storage compartment of approximately 8 tons/minute, with three rotary air locks mounted to the hoppered storage compartment, and three approximately 100 HP diesel engines driving 900 cfm blowers, available from Gardner Denver (screw type tend to be much quieter and more dependable) and a small hydraulic pump to drive the rotary air lock(s). Moreover, the design can include hydraulic dolly legs to lower the trailer to the ground in order to facilitate the drive over ramp functionality. The system width is approximately 12 feet and its height is approximately 14 feet. These are transport dimensions, not working dimensions. Each blower is connected to a rotary drop out air lock. This provides redundancy, so that if one engine or airlock fails, two others would be interchangeable with each other.

Adding multiple blowers and airlocks provides modular addition of transfer rate which increases incrementally to suit requirements of the user.

FIGS. 15-17show an alternative proppant handling system400that can be used at a worksite to conveniently transfer proppant from a gravity feed trailer or proppant delivery container into a silo or other storage container onsite, pneumatically.

The proppant handling system400inFIGS. 15-17is similar in some ways to the proppant handling system100inFIGS. 12-14. For example, the proppant handling system400inFIGS. 15-17has two proppant unloading stations102, two mechanical conveying systems104, a proppant holding container106, and a pneumatic conveying system108. Each proppant unloading station102is configured to receive proppant from a gravity feed trailer or container positioned above the proppant unloading station102. Each mechanical conveying system104is configured to convey proppant from an associated one of the proppant unloading stations102to an opening in the top of the proppant holding container106. The pneumatic conveying system108is configured to pneumatically convey proppant from the proppant holding container106to one or more off-system destinations (e.g., a silo, blender hopper, etc.).

The proppant handling system400inFIGS. 15-17differs from the proppant handling system100inFIGS. 12-14in at least a few notable ways.

First, for example, the number and specific arrangement of components in the proppant handling system400is different than the number and specific arrangement of components in the proppant handling system100inFIGS. 12-14. More particularly, in system400, there are six air blowers126and six air locks124. The six air blowers126are arranged with three on each lateral side of the chassis101. Each air blower126is driven by an electrical motor. Likewise, the six air locks124are arranged with three on each lateral side of the chassis101. The proppant holding container406in system400has a lower surface that forms six hoppers120, each of which has a corresponding discharge opening (or outlet)122at its bottom, and each of which is aligned with (and connected to) a corresponding one of the air locks124.

In various implementations, the system400will include valves that enable any one of the six air blowers126and six air locks to be connected to the same pneumatic conveying channel(s).

An another example of how the proppant handling system400ofFIGS. 15-17differs from the proppant handling system100ofFIG. 12-14, is that the proppant handling system400has an electrical generator set429together, with the fuel tank128, on a raised section of the chassis101near the forward end of the chassis101. The fuel tank128supplies fuel to an internal combustion engine of the electrical generator set429. The electrical generator set429produces electricity that can be used to power any one or more of the other system components, including, for example, the air blowers126, the air lock(s), the ramp panels, etc.

In some implementations, the proppant pneumatic transfer rate of the system400is in the 3.6 ton per minute range with approximately 70 tons of storage. This equals about 20 minutes of sand conveying if trucks are not available; or equivalently a 28 ton truck load may be unloaded in less than 8 minutes.

FIG. 18shows an unloader kit1891for unloading a proppant delivery container, such as a container made by the SandBox Logistics™ Company, into a system like the ones disclosed herein. More specifically, the illustrated implementation shows three such proppant delivery containers1890. Each proppant delivery container has a bottom surface that defines pockets1899for a forklift to engage, so that the forklift can lift the proppant delivery container1890onto and off of the unloader kit1891.

The unloader kit1891can be attached to a hauling vehicle and hauled. The hauling vehicle would be coupled to the front of the unloader kit1891(which is on the right side of the image as shown) and would roll on its axle1892at a rear end thereof (the left side of the image as shown). The unloader kit1891is shown positioned over the ramp panels and unloading station of a system (e.g., system1100).

The unloader kit1891has a platform1893that supports the proppant delivery containers1890and a drive mechanism (e.g., a chain drive) that can advance the proppant delivery containers1890across the platform (e.g., from left to right in the illustrated implementation). The left most proppant delivery container1890in the illustrated implementation is a full (having been placed onto the platform without having been unloaded yet), the right most proppant delivery container1890in the illustrated implementation is empty (having passed the proppant unloading station1102and been unloaded), the center proppant delivery container1890in the illustrated implementation is being unloaded (into the proppant unloading station1102immediately below its bottom discharge port.

The illustrated platform1893is supported by a plurality of leveling legs1895(or jacks), some of which sit atop pads1894.

In a typical implementation, the system includes a box advancing mechanism (e.g., a gearbox and motor, electric or hydraulic, that can advance the box container to the unloading and emptying positions on the box unloader kit). In a typical implementation, the kit has rollers (that the boxes can roll on, atop the platform) and a chain drive to drive a chain for moving the boxes. In some implementations, the sand box is a size of about 8 feet wide by 9 feet high, by 20 feet long.

For example, the number of system component can vary considerably from system to system. For example, in various implementations, a system might have any number (one or more) proppant unloading stations, mechanical conveyor systems, dust collectors, proppant holding containers, air locks, and/or air blowers. Moreover, the arrangement of system components on a particular chassis can vary as well. As an example, in some implementations, the proppant holding container may be positioned near the front of the chassis, with the proppant unloading station near the rear of the chassis.

The chassis can be virtually any kind of supporting frame for the other components of the material handling system described herein. It can be made of a variety of different materials or combinations of materials and have a variety of different physical configurations. Prime movers can be virtually any kind of internal combustion engines, electric motors, pneumatic motors, hydraulic motors, etc.

The air blower assemblies1126can have any one of a variety of different physical configurations.

Other support equipment may be included. If, for example, the ramps and/or other equipment (e.g., jacks, etc.) are hydraulically-driven, then the system would include one or more hydraulic pumps and a system for delivering pressurized hydraulic fluid from those hydraulic pump(s) to the ramps and/or other equipment.

In some implementations, the air locks may include dense phase/dilute phase pneumatic conveying technologies, including, for example, such technologies available from the Schenck Process Company. Moreover, in some implementations, the air lock may include dense phase pressure vessels, such as the dense phase pressure vessels, available from the Coperion GmbH.

The mechanical conveyor system can include any one or more of a variety of different mechanical elements and components to mechanically convey material (e.g., the proppant) from the proppant unloading station into the proppant holding container. For example, in some implementations, the mechanical conveyor system may include any number of (one or more) conveyors. Alternatively, or additionally, the mechanical conveyor system could include one or more different types of mechanical conveyor technologies including, for example, screw conveyors, drag chain conveyors, belt conveyors, vibrating conveyors, vertical conveyors, spiral conveyors etc. and/or any combination thereof. Mechanical conveyor systems that use belts can have virtually any size belts. If the system includes only one single conveyor belt, that single belt might have a horizontal portion that extends from the unloading station to a bend and then an angled portion that extends from the bend to the top of the mechanical conveyor system.

The transfer rate or conveying rate for a particular mechanical conveyor system may vary. For example, in a system that includes a single mechanical conveyor system the transfer rate or conveying rate for that single mechanical conveyor system may be between 5 and 15 tons per minute (e.g., 10 tons per minute). Additional mechanical conveyor systems will increase the overall transfer rate or conveying rate by the transfer rate of the additional mechanical conveyor system(s). In one exemplary implementation, each air blower1126has a capacity of about 1000 standard cubic-feet per minute. The capacity of the air blower, and all other components of the system, can vary considerably.

The dust collector could be incorporated into the storage tank and deposit the collected dust into the tank. The vacuum system, in those implementations, would draw air from the tank and conveyor system.

The proppant holding container may have any one of a variety possible sizes (storage capacities), shapes, and styles. The proppant holding container can have any number of (one or more) hoppers-airlocks-discharges.

The ramps could be completely separate objects which are transported separately and put in place (e.g., as shown inFIGS. 5-8) for work.

In some implementations, the system disclosed herein has only one proppant unloading station, whereas in other implementations, the system disclosed herein has two (or possibly more than two) proppant unloading stations. In implementations that include only one proppant unloading station, a trailer may have to move in order to unload each trailer hopper. In implementations that have more than one proppant unloading station, the trailer may be able to unload more than one trailer hopper (one into each proppant unloading station) simultaneously. The system components can be connected, or connectable, together in any one of a variety of possible ways—to facilitate system redundancy and to facilitate ramping up (or down) system capacity. Moreover, in some implementations, one or more of the components may be physically separate from (and not mounted on the same chassis as) the other system components. For example, in some implementations, the drive over conveyor may be provided as a separate piece of equipment from the other system components. In those implementations, a mechanical conveyor would be provided to mechanically convey material from the drive over conveyor to the separate container. As another example, the blowers may be provided as a separate piece of equipment. In those implementations, the blowers would be connected to the air locks at the bottom of the storage container by pneumatic lines. In general, any system component(s) provided on a separate base (e.g., not mounted on the same chassis as the other system components) would be operationally connected into the system (and to the other system components) as shown in the drawings and otherwise described herein to the other system components. In some implementations, more than one of the system components may be provided as a physically discrete component (and not mounted on the same chassis as the other system components).

Similarly, while operations are disclosed herein as occurring in a particular order, this should not be understood as requiring that such operations be performed in the particular order shown or in sequential order, or that all represented operations be performed, to achieve desirable results.

The systems described herein are material handling system. These systems can be used, of course, to deliver proppant (e.g., sand, treated sand, or man-made ceramic materials) designed to keep an induced hydraulic fractures open, during or following a fracturing treatment, or to deliver any one of various other types of solid materials (e.g., any bulk powder or granular material; sand, grain, cement, powdered chemicals, salt, etc.)

The system is described as being useful at a worksite (e.g., one that includes one or more hydraulic fracturing wellheads). The worksite need not have actual wellheads in place though. Instead, a worksite could be a location where fracking is intended to take place, but where not wellheads are in place yet. The worksite could also be at a temporary storage location. The worksite could also be at a material processing site. The system could work for any bulk powder or granular material; sand, grain, salt, etc.

The system described herein is portable. Portability, however, may be provided for in a variety of other ways than just those explicitly mentioned herein.

Other implementations are within the scope of the claims.