System for Transporting Sand for Wellbore Operations

Abstract

A transport system for carrying a proppant, the system comprising a loading tower, a first transfer tower, a second transfer tower and an unloading tower. The loading tower is located proximate a loading area while the unloading tower is located proximate an unloading area. The system also includes a first transfer tower and a second transfer tower. A first aerial cable conveys a transfer container from the loading tower to the first transfer tower, while a second aerial cable conveys the transfer container from the second transfer tower to the unloading tower. The transfer container is configured to be suspended from the first and second aerial cables en route from the loading tower to the unloading area. Sand or supplies from the transfer container is received at the unloading area for use in a wellbore operation. Methods of transporting sand for use in wellbore fracturing operations are also provided.

Claims

1. A transport system, comprising: a loading tower located proximate a loading area; a first transfer tower located proximate a transfer area; a second transfer tower also located proximate the transfer area; an unloading tower located proximate an unloading area; a first aerial cable extending from the loading tower to the first transfer tower; a second aerial cable extending from the second transfer tower to the unloading tower; a transfer container, wherein the transfer container is configured to be suspended from the first and second aerial cables en route from the loading tower to the unloading tower; and a staging area located proximate one or more well sites undergoing downhole well operations; and wherein: the staging area is located at or proximate the unloading area, and the transfer container is configured to hold materials in support of the downhole well operations.

2. The transport system of claim 1, further comprising: two or more intermediate towers placed between the loading tower and the first transfer tower for supporting the first aerial cable and the transfer container above ground; and two or more intermediate towers placed between the second transfer tower and the unloading tower for supporting the second aerial cable and the transfer container above ground.

3. The transport system of claim 2, wherein: the downhole well operations comprise formation acidizing; and the transfer container is configured to hold an acid in fluid form.

4. The transport system of claim 2, wherein: the downhole well operations comprise formation fracturing; the transport system comprises a plurality of transfer containers; and each transfer container is configured to hold frac proppant, frac iron, frac chemicals or field personnel.

5. The transport system of claim 4, wherein: the frac proppant is sand; at least some of the plurality of transfer containers are configured to hold sand to be used in the formation fracturing operation, and to serve as sand boxes; and the staging area is dimensioned to receive over 100 sand boxes.

6. The transport system of claim 5, wherein the sand boxes have been loaded with sand prior to arrival at the loading area.

7. The transport system of claim 5, wherein each of the plurality of transfer containers is configured to be suspended from the first and second aerial cables en route from the loading tower to the unloading tower by means of a grip assembly.

8. The transport system of claim 7, wherein each grip assembly comprises: one or more rollers or sheaves configured to contact an aerial cable; and a hook configured to releasably connect to and support a transfer container.

9. The transport system of claim 8, wherein: each of the plurality of transfer containers comprises a latching mechanism dimensioned to receive the hook, allowing the hook and latching mechanism to support a respective transfer container along the first and second aerial cables.

10. The transport system of claim 9, wherein: a distance from the loading area to the transfer area is at least one mile; and a distance from the transfer area to the unloading area is also at least one mile.

11. The transport system of claim 10, wherein: the plurality of transfer containers holds at least 500 ft.sup.3 of sand; and the sand unloading area is configured to receive at least 200 transfer containers per day, in series, from the second aerial cable.

12. A method of transporting proppant to a wellsite, comprising: receiving a plurality of transfer containers at a loading area, wherein each of the transfer containers is in modular form; transporting each of the plurality of transfer containers from the loading area to a transfer area, in series, via a first aerial cable conveyance system, wherein each of the transfer containers is loaded with frac sand; moving each of the transfer containers from the first aerial cable conveyance system to a second aerial cable conveyance system; transporting each of the plurality of transfer containers from the transfer area to an unloading area, in series, via the second aerial cable conveyance system; and removing the sand from each of the transfer containers for use in a wellbore fracturing operation.

13. The method of claim 12, wherein: the first aerial cable conveyance system comprises: a loading tower located proximate the loading area; a first transfer tower located proximate the transfer area; two or more intermediate towers placed between the loading tower and the first transfer tower; and a first aerial cable extending from the loading tower, across the two or more intermediate towers, and the first transfer tower for supporting the transfer containers above ground; and wherein the second aerial cable conveyance system comprises: a second transfer tower located proximate the transfer area; an unloading tower located proximate the unloading area; two or more intermediate towers placed between the second transfer tower and the unloading tower; and a second aerial cable extending from the second transfer tower, across the two or more intermediate towers, and the unloading tower for also supporting the transfer containers above ground.

14. The method of claim 13, wherein: each of the plurality of transfer containers: has been delivered to the loading area by means of a truck; is configured to be loaded onto a truck by means of a fork lift; and is pre-loaded with frac sand upon arrival at the unloading area; and the method further comprises: securing each of the transfer containers to the first aerial cable; and upon arrival at the transfer area, securing each of the transfer containers to the aerial second cable.

15. The method of claim 14, wherein: removal of sand from each of the transfer containers results in a plurality of empty transfer containers; and the method further comprises, following removal of the sand from each of the transfer containers: transporting each of the empty transfer containers from the unloading area back to the transfer area, in series, via the second aerial cable conveyance system; and upon arrival at the transfer area, transporting each of the empty transfer containers from the transfer area back to the loading area, in series, via the first aerial cable conveyance system.

16. A method of transporting supplies to a wellsite, comprising: receiving a plurality of transfer containers at a loading area; securing each of the plurality of transfer containers to a first cable along a first aerial cable conveyance system; transporting each of the plurality of transfer containers along the first cable, in series, from the loading area to a transfer area; securing each of the plurality of transfer containers to a second cable along a second aerial cable conveyance system; transporting each of the plurality of transfer containers along the second cable, in series, from the transfer area to an unloading area; and placing each of the transfer containers at a staging area located proximate one or more well sites, wherein the one or more well sites is undergoing downhole well operations.

17. The method of claim 16, wherein the first aerial cable conveyance system comprises: a loading tower located proximate the loading area; a first transfer tower located proximate the transfer area; and two or more intermediate towers placed between the loading tower and the first transfer tower; and wherein the first cable extends from the loading tower, across the two or more intermediate towers, and to the first transfer tower and supports the transfer containers above ground.

18. The method of claim 17, wherein the second aerial cable conveyance systems comprises: a second transfer tower located proximate the transfer area; an unloading tower located proximate the unloading area; and two or more intermediate towers placed between the second transfer tower and the unloading tower; and wherein the second aerial cable extends from the second transfer tower, across the two or more intermediate towers, and to the unloading tower to further support the transfer containers above ground.

19. The method of claim 18, wherein: the downhole well operation comprises formation acidizing; and at least some of the transfer containers are configured to hold acid in fluid form.

20. The method of claim 18, wherein: the downhole well operation comprises formation fracturing; and each of the transfer containers is configured to hold frac sand, frac iron, frac chemicals or field personnel.

21. The method of claim 20, wherein: at least some of the plurality of transfer containers are configured to hold sand to be used in the formation fracturing operation, to serve as sand boxes; and the staging area is dimensioned to receive over 200 sand boxes per day.

22. The method of claim 21, wherein: a distance from the loading area to the transfer area is at least one mile; a distance from the transfer area to the unloading area is also at least one mile; and

23. The method of claim 21, wherein each of the plurality of transfer containers has been pre-loaded with sand prior to arrival at the loading area.

24. The method of claim 23, wherein each of the plurality of transfer containers: has been delivered to the loading area by means of a truck; is configured to be loaded onto the truck by means of a fork lift; securing each of the plurality of transfer containers to a first cable comprises latching each of the transfer containers to the first cable; and securing each of the plurality of transfer containers to a second cable comprises latching each of the transfer containers to the second cable.

25. The method of claim 20, wherein: each of the transfer containers is configured to be suspended from the first and second aerial cables en route from the loading tower to the unloading tower by means of a grip assembly.

26. The method of claim 25, wherein each grip assembly comprises: one or more rollers or sheaves configured to contact an aerial cable; and a latching mechanism configured to releasably connect to and support a transfer container; and wherein each of the plurality of transfer containers comprises a latching mechanism dimensioned to receive the hook, allowing the hook and latching mechanism to support a respective transfer container along the first and second aerial cables.

27. The method of claim 20, wherein each sand box holds at least 500 ft.sup.3 of sand.

28. A method of transporting supplies to a wellsite, comprising: receiving a plurality of transfer containers at a loading area; transporting each of the plurality of transfer containers from the loading area to a transfer area, in series, via a first aerial cable conveyance system; selecting from one of a plurality of second aerial cable conveyance systems, wherein each of the second aerial cable conveyance systems terminates at a different unloading area; moving each of the transfer containers from the first aerial cable conveyance system to the selected second aerial cable conveyance system; transporting each of the plurality of transfer containers from the transfer area to the unloading area of the selected second aerial cable conveyance system, in series; placing each of the transfer containers at a staging area located proximate one or more well sites, wherein the one or more well sites is undergoing formation fracturing operations.

29. The method of claim 28, wherein: the first aerial cable conveyance system comprises: a loading tower located proximate the sand loading area; a first transfer tower located proximate the transfer area; two or more intermediate towers placed between the loading tower and the first transfer tower; and a first aerial cable extending from the loading tower, across the two or more intermediate towers, and the first transfer tower for supporting the transfer container above ground; and each of the second aerial cable conveyance systems comprises: a second transfer tower located proximate the transfer area; an unloading tower located proximate a sand unloading area; two or more intermediate towers placed between the second transfer tower and the unloading tower; and a second aerial cable extending from the second transfer tower, across the two or more intermediate towers, and the unloading tower for further supporting the transfer containers above ground.

30. The method of claim 29, wherein: the transfer containers are configured to be suspended from the first and second aerial cables en route from the loading tower to the unloading tower by means of a grip assembly; and each grip assembly comprises: one or more rollers configured to move across an aerial cable; and a hook configured to releasably connect to and support a transfer container; and wherein each of the transfer containers comprises a latching mechanism dimensioned to receive the hook, allowing the hook to support a respective transfer container along the first and second aerial cables.

31. The method of claim 30, wherein: each of the transfer containers is configured to hold frac sand, frac iron, frac chemicals or field personnel; a distance from the sand loading area to the transfer area is at least one mile; and a distance from the sand transfer area to the unloading area is also at least one mile

32. The method of claim 31, wherein each of the plurality of transfer containers: is configured to hold at least 500 ft.sup.3 of sand; at least some of the plurality of transfer containers has been pre-loaded with sand prior to arrival at the loading area, serving as sand boxes; and the staging area is dimensioned to receive over 100 sand boxes.

33. The method of claim 32, wherein each of the sand boxes: has been delivered to the loading area by means of a truck; and is configured to be loaded onto the truck by means of a fork lift.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0037] So that the manner in which the present inventions can be better understood, certain illustrations, charts and/or flow charts are appended hereto. It is to be noted, however, that the drawings illustrate only selected embodiments of the inventions and are therefore not to be considered limiting of scope, for the inventions may admit to other equally effective embodiments and applications.

[0038] FIG. 1 is a schematic view of a known well site. The well site is set up to conduct a hydraulic fracturing operation.

[0039] FIG. 2 is a schematic view of a sand logistics operation of the present invention, in one embodiment. Sand is transported from one of several mines, to a loading area for distribution to well sites.

[0040] FIG. 3A is a perspective view of a transfer container as may be used in the transport system of the present invention, in one embodiment.

[0041] FIG. 3B is a side view of a plurality of transfer containers, formed as individual and stackable modules.

[0042] FIG. 3C is a side view of a single illustrative transfer container. Here, the transfer container is being lifted and moved via forklift.

[0043] FIG. 3D is a somewhat schematic side view of a truck delivering a transfer container to a loading area. The transfer container has been loaded onto a trailer of the truck using the fork lift of FIG. 3C.

[0044] FIG. 4 is a side view of an illustrative transport system of the present invention, in one embodiment. Stackable, portable and modular transfer containers are shown at a loading area, a transfer area and an unloading area.

[0045] FIG. 5 is a schematic view of a transport system of the present invention, in an alternate embodiment.

[0046] FIG. 6 is a flow chart showing steps for a method of transporting materials or personnel to selected well sites.

DETAILED DESCRIPTION OF CERTAIN EMBODIMENTS

Definitions

[0047] Various terms as used in the specification and in the claims are defined below. To the extent a term used in the claims is not defined below, it should be given the broadest reasonable interpretation that persons in the upstream oil and gas industry have given that term as reflected in at least one printed publication or issued patent.

[0048] For purposes of the present application, it will be understood that the term hydrocarbon refers to an organic compound that includes primarily, if not exclusively, the elements hydrogen and carbon. Hydrocarbons may also include other elements such as, but not limited to, halogens, metallic elements, nitrogen, oxygen, and/or sulfur.

[0049] As used herein, the term hydrocarbon fluids refers to a hydrocarbon or mixtures of hydrocarbons that are gases or liquids. For example, hydrocarbon fluids may include a hydrocarbon or mixtures of hydrocarbons that are gases or liquids at formation conditions, at processing conditions, or at ambient condition. Hydrocarbon fluids may include, for example, oil, natural gas, coalbed methane, shale oil, pyrolysis oil, pyrolysis gas, a pyrolysis product of coal, and other hydrocarbons that are in a gaseous or liquid state, or combination thereof.

[0050] As used herein, the terms produced fluids, reservoir fluids and production fluids refer to liquids and/or gases removed from a subsurface formation, including, for example, an organic-rich rock formation. Produced fluids may include both hydrocarbon fluids and non-hydrocarbon fluids. Production fluids may include, but are not limited to, oil, natural gas, pyrolyzed shale oil, synthesis gas, a pyrolysis product of coal, oxygen, carbon dioxide, hydrogen sulfide and water.

[0051] As used herein, the term fluid refers to gases, liquids, and combinations of gases and liquids, as well as to combinations of gases and solids, combinations of liquids and solids, and combinations of gases, liquids, and solids.

[0052] As used herein, the term subsurface refers to geologic strata occurring below the earth's surface.

[0053] As used herein, the term formation refers to any definable subsurface region regardless of size. The formation may contain one or more hydrocarbon-containing layers, one or more non-hydrocarbon containing layers, an overburden, and/or an underburden of any geologic formation. A formation can refer to a single set of related geologic strata of a specific rock type, or to a set of geologic strata of different rock types that contribute to or are encountered in, for example, without limitation, (i) the creation, generation and/or entrapment of hydrocarbons or minerals, and (ii) the execution of processes used to extract hydrocarbons or minerals from the subsurface.

[0054] The term sand refers to any granular material containing quartz or silica (meaning a combination of silicon and oxygen, or SiO2). Non-limiting examples include Northern White sand and or West Texas eolian sand. Sand is one form of proppant that may be used in a formation fracturing operation.

[0055] The term aggregate refers to an inorganic mixture containing sand.

[0056] As used herein, the term wellbore refers to a hole in the subsurface made by drilling or insertion of a conduit into the subsurface. A wellbore may have a substantially circular cross section. The term well, when referring to an opening in the formation, may be used interchangeably with the term wellbore.

[0057] A well site is a surface area where a wellbore is being or has been formed.

Description of Selected Specific Embodiments

[0058] Described herein is a transport system used to convey frac sand or other material. Also described are methods for transporting frac sand for use in wellbore fracturing operations.

[0059] FIG. 1 is a schematic view of a well site 100 undergoing a completion operation. More specifically, the well site 100 is undergoing a high-pressure fluid injection operation. The operation may include an acid treatment of a subsurface formation. However, the operation principally represents a hydraulic fracturing operation.

[0060] The well site 100 is placed on a so-called well pad 110. The well pad 110 represents an area where the ground surface has been prepared for drilling and completion operations. The pad 110 may be, for example, two to four acres. In some cases, more than one well may be drilled and completed on a single pad, with each well being completed in the same horizontal plane but in a different azimuth, or optionally along different horizontal planes.

[0061] The well site includes a series of sand bins 120. The sand bins 120 may be trailers carried to the well pad 110 using trucks. The sand bins 120 may be pre-filled with sand, or may be filled with sand using a separate sand truck 125. Alternatively, the sand bins 120 may actually each be a sand truck.

[0062] The well site also includes a frac tree 165. The frac tree 165 is disposed over a wellbore (not shown) and includes a series of vertically-stacked flow control valves. The flow control valves control the high-pressure injection of fracturing fluids into the wellbore. It is understood that the current inventions are not limited by the architecture of the well tree or the nature of well completion.

[0063] The well site 100 also includes frac storage tanks 130. The frac storage tanks 130 have been brought on location 110 using trucks. In one aspect, the frac storage tanks 130 represent trailers having water tanks that are brought to the location 100 by trucks. More preferably, the frac storage tanks 130 are stationary tanks that are filled by water transport trucks 135. In either instance, the tanks 130 contain water (typically brine) used as the carrier medium for the injection fluid.

[0064] FIG. 1 also shows that chemical storage trucks 140 have been driven onto the pad 110. The chemical storage trucks 140 carry surfactants or other chemicals (typically referred to as slickwater) that are mixed with the brine of the frac storage tanks 130 to reduce friction. The chemicals may also optionally include biocides, scale inhibitors and stabilizers as well as guar gum, which is used as a thickening agent. The chemicals are mixed along with sand into the brine using so-called frac blenders 145.

[0065] The well site 100 of FIG. 1 also shows a series of frac pumps 150. Each of the frac pumps 150 is preferably part of a truck that is configured to receive injection fluids from frac blenders 145, and then send the fluids under high pressure through a high-pressure injection line (shown partially at 150) In some cases, the frac pumps deliver the slurry to a so-called frac missile (not shown). A service truck 155 may be used to provide tools and equipment such as so-called frac iron. It is understood that FIG. 1 is merely illustrative; the inventions herein are not limited to an exact arrangement of trucks, pumps, tanks, blenders or frac iron.

[0066] As noted, between the frac pumps 150 and the frac tree 165 is a high pressure injection line 150. A pressure relief valve (not shown) is typically provided along the injection line 150. In the event a pressure is detected along the high-pressure injection line 150 that exceeds a designated threshold pressure, the pressure relief valve (or frac relief valve or FRV) is opened. Injection fluids are then diverted to an open relief pit 160.

[0067] In an actual hydraulic fracking operation, fluids are pumped into different longitudinal portions of a horizontal wellbore in stages. In addition, a series of different fluids may be pumped into each stage, including for example an acid stage, a slickwater stage (having no proppant), a proppant stage and a flushing stage. This application is not intended to be a primer on hydraulic fracturing, and the person of ordinary skill in the art will be familiar with the fracking process. For purposes of the present disclosure, all of these fluids, individually and together, are considered injection fluids or fracturing fluids.

[0068] Current completion operations operate under the principle that more sand is better. It is estimated that a standard horizontal well now uses between 1,900 pounds (nearly 1 ton) and 3,000 pounds (1.5 tons) of sand per lateral foot. A 10,000 foot lateral well may consume 12 million to 25 million pounds (6,000-12,500 tons) of proppant, which is mixed into a water-based slurry using mixers and blenders. While only a few illustrative sand bins/trailers 120 are shown, it is understood that a fracturing operation for a 10,000 foot lateral well may require a delivery of sand by over 450 trucks. A single frac crew can place downhole 4 million pounds or more of sand in a day, emptying 100 dry bulk trailers every 24 hours.

[0069] The last-mile logistics for moving frac sand involves transportation by heavy truck haulers, each carrying approximately 22.5 tons of sand. As discussed in detail above, the delivery of sand and other materials to a well site 110 causes considerable strain upon state and county roads and resources. Sand delivery by truck is expensive and contributes to road infrastructure deterioration and traffic congestion. In addition, sand hauling via truck requires a large number of drivers that are currently in short supply in the United States. Therefore, an improved proppant delivery system is needed, particularly in wells being completed in such areas as the Delaware Basin, the Midland Basin and the Bakken Shale.

[0070] FIG. 2 is a schematic view of a logistics map 200 for transporting sand to various well sites 100 according to the present invention, in one embodiment. The intent is to reduce the number of transport vehicles needed incident to well completion activities, particularly in connection with hydraulic fracturing and other well completion operations.

[0071] The logistics map 200 first shows a plurality of sand sources, or mines 210. Specifically, three illustrative mines 210A, 210B and 210C are shown. Each mine 210A, 210B, 210C represents an area where a permit has been issued to extract sand suitable for formation proppant. Appropriate leases have been obtained from the land owners, or the land has been purchased by mining companies.

[0072] The sand mines 210A, 210B, 210C may be adjacent to one another or may be located in different counties. Indeed, they may even be located in different states. In any event, the sand is procured and then transported to a processing facility 220. The processing facility 220 is used to filter rocks and larger aggregate (and any organic matter), leaving behind quartz or silica of a desirable mesh size.

[0073] For sand mine 210A, the sand is transported via line 212; for sand mind 210B, the sand is transported via line 214; and for sand mine 210C, the sand is transported via line 216. Lines 212, 214 and 216 may represent short conveyor systems. Alternatively, they may represent railroad spurs or perhaps longer rail lines. Alternatively still, lines 212, 214, 216 may be county roads or interstate highways, with the sand being carried in over-the-road trailers via Full-Truck-Load (or FTL) trucks. In any instance, the sand is filtered and processed at the processing facility 220 and is ready for delivery to an area where oilfield operations are taking place.

[0074] In the map 200 of FIG. 2, the filtered sand is transported to a receiving area 230. Transport is made via line 225, which typically includes a plurality of over-the-road trucks carrying trailers or, in some instances, boxes of sand. Upon arrival, a series of sand bins or silos 235 are provided for temporary storage. It is understood that in many areas where sand might be held (such as western North Dakota, eastern New Mexico or West Texas), ambient wind can actually blow the sand away. Therefore, the sand is typically held in bins or silos 235. Alternatively, the sand may be held in closed-top containers.

[0075] In the present methods, the receiving area 230 serves as a loading station. Many well completion operations are conducted in remote locations. Therefore, it is preferred that the receiving area 230 be located near a truck stop, or near a rural gas station and restaurant.

[0076] From the receiving area, sand is carried to a transfer area 240 via line 234. From there, the sand is delivered to any of a plurality of unloading areas 250A, 250B, 250C. Each unloading area is preferably associated with a well site, such as well site 100 of FIG. 1, the exception being that far fewer sand bins 120 or sand delivery trucks 125 are required.

[0077] The logistics map 200 shows separate lines for transporting sand from the transfer area 240 to the unloading areas 250A, 250B, 250C. Sand is transported to unloading area 250A via line 242. Similarly, sand is transported to unloading area 250B via line 244. Similarly still, sand is transported to unloading area 250C via line 246.

[0078] In order to reduce or even eliminate the use of delivery trucks 125 to the well sites 250A, 250B, 250C, line 234 is provided as an aerial cable conveyance system. Similarly, lines 242, 244 and 246 also represent aerial cable conveyance systems. The aerial conveyance systems transport large cargo boxes, referred to herein as transfer containers, via respective cables. The cables cross over roads and greatly eliminate congestion on state and county highways while expediting delivery of proppant, materials and even personnel to well sites.

[0079] FIG. 3A is a perspective view of a transfer container 300 as may be used in a transport system of the present invention, in one embodiment. (A transport system is shown schematically in FIG. 4). The transfer container 300 represents a cargo box having four sides 310 and a base 312. Preferably, each container 300 has a normally-closed top having a hatch for opening during sand loading, and has a gate at the base 312 for sand unloading. An internal compartment 315 is formed by the sides 310 and the base 312. Various support rails 316 are placed along the sides 310 providing structural integrity.

[0080] In one embodiment, the transfer container 300 is 10 feet by 5 feet, or other dimension providing for a volume of about 500 ft.sup.3. When substantially full of sand, the transfer container 300 may weigh 45,000 to 50,000 pounds or more. Accordingly, the support rails 316 are fabricated from an extremely durable material such as steel, carbon-fiber material or graphite fiber material.

[0081] The transfer container 300 is designed to be stackable and scalable. FIG. 3B is a side view of a plurality of transfer containers 300B, in stacked relation. The individual transfer containers 300 may be moved and stacked using a fork lift.

[0082] FIG. 3C is a side view of a single illustrative transfer container 300. Here, the transfer container 300 is being lifted and moved via forklift 360. The fork lift 360 may stack boxes 300B, or may move boxes 300 onto a trailer for delivery.

[0083] FIG. 3D is a schematic side view of a truck 370. The truck 370 includes a flatbed trailer 375 hitched there behind. In this view, a transfer container 300 has been loaded onto the trailer 375 such as by using the fork lift 360 of FIG. 3C. It is understood that a flatbed trailer 375 may be dimensioned to carry multiple transfer containers 300.

[0084] Returning to FIG. 3A, the transfer container 300 is designed to be hoisted and then carried along a cable 340. Hoisting may be done using a winch line or by the fork lift 360. In the illustrative arrangement of FIG. 3A, a latching system is provided. The latching system includes a series of eye bolts 320 and a series of support cables 322. The cables 322 all lead to a central eye bolt 325. The central eye bolt 325, in turn, is picked up by a hook 330 for latching.

[0085] There are, or course, various alternative latching systems for the hook 330 to capture the transfer container 300. The current inventions are not limited to any particular means for supporting and carrying a transfer container 300 along the cable 340 unless so expressly stated in the claims. For purposes of the present disclosure, any such means may be referred to as latching. Thus, securing each of the plurality of transfer containers 300 to a cable 340 and hook 330 comprises latching each of the transfer containers 300 to the cable 340.

[0086] It is noted in FIG. 3A that a pair of opposing towers 350 is shown. The towers 350 support and suspend the cable 340. The towers 350 may be, for example 0.25 km apart, or 0.5 km apart, or up to 1 km apart. The towers 350 are configured to allow the hook 330 to carry transfer containers 300 from tower 350 to tower 350, with the towers 350 leading to designated areas that are part of a transport system.

[0087] To facilitate the transfer of transfer containers 300 from tower 350 to tower 350, a grip assembly 335 is provided. The grip assembly 335 includes a plurality of wheels 332 residing above and below the cable 340. The wheels 332 ride along the cable 340 and are held within a block 334. The block 334, in turn, supports the hook 330.

[0088] To move the transfer containers 300 from tower 350 to tower 350, an electrical power source is provided. The electrical power source may be an on-board battery, or a combination of a battery and a capacitor. Alternatively, the power source may be a power cable (not shown) that is suspended between the towers 350 adjacent the cable 340. Alternatively still, the cable 340 itself may be electrified. In this instance, the hook 330 and block 334 will preferably be heavily insulated. In any instance, CO.sub.2 emissions will be reduced by reducing the number of large trucks traversing the highways and idling en route to well sites.

[0089] Some combination of these power sources may be considered. In any instance, power is supplied to on-board motors (not shown) associated with the wheels 332. Specifically, a plurality of small motors (not shown) may be provided along the block 334. The motors rotate shafts connected to the respective wheels 332. The shafts cause the wheels 332 to turn, moving the block 334 and suspended transfer containers 300 along the cable 340, from tower 350 to tower 350.

[0090] As an alternative, the cable 340 may be a looping steel cable. In this instance, the steel cable 340 moves across sheaves (not shown) placed between and along the towers 350. In this instance, the cable 340 is driven by a bullwheel (not shown) located in a terminal. The bullwheel, in turn, is driven by an electrical motor or a combustible engine. The block 334 and connected hook 330 are then fixed along the cable 340. In other words, the cable 340 moves the hook 330 rather than the hook 330 self-conveying along the cable 340.

[0091] It is understood that the present inventions are not limited by the mechanical and electrical systems used for transporting the transfer containers 300 along the cable 340 unless so expressly stated in the claims.

[0092] FIG. 4 is a side view of an illustrative transport system 400 of the present invention, in one embodiment. The transport system 400 is designed to carry transfer containers 300 across cables 414, 424. One illustrative transfer container 300 is shown being supported by each of cables 414 and 424. However, it is understood that each cable 414, 424 may and likely will transport a plurality of transfer containers 300, in series, at the same time.

[0093] Each cable 414, 424 is associated with a separate aerial cable conveyance system. Cable 414 is associated with a first aerial cable conveyance system 435, while cable 424 is associated with a second aerial cable conveyance system 445. The first aerial cable conveyance system 435 moves transfer containers 300 from a receiving area 430 to a transfer area 440. Similarly, the second aerial cable conveyance system 445 moves transfer containers 300 from the transfer area 440 to an unloading area 450.

[0094] The receiving area 430 may be, for example, the sand gathering area 230 of FIG. 2. Similarly, the unloading area 450 may be any of the unloading areas 250A, 250B or 250C of FIG. 2.

[0095] A plurality of transfer containers 300 are seen in each of the receiving area 430, the transfer area 440 and the unloading area 450. The illustrative transfer containers 300 are stackable, portable and modular. Preferably, each transfer container 300 is designed to hold frac sand. Preferably, the transfer containers 300 arrive at the receiving area 430 pre-loaded with the frac sand.

[0096] It is understood that the transfer containers 300 may be configured to carry other supplies. Such other supplies may include chemicals, water, pumps, cleaning supplies, personal supplies, frac iron or oilfield tubulars. Indeed, the transfer containers 300 may even be configured to transport personnel and food across job sites.

[0097] The first aerial cable conveyance system 435 includes a loading tower 410 and a transfer tower 410. The towers 410, 410 support the cable 414. The loading tower 410 is proximate the loading area 430, while the transfer tower 410 is proximate the transfer area 440. Intermediate the two towers 410, 410 is a plurality of intermediate towers 415. The number of intermediate towers 415 is a function of the distance between towers 410 and 410 and the loads to be borne by the cable 414.

[0098] The second aerial cable conveyance system 445 includes a transfer tower 420 and an unloading tower 420. The towers 420, 420 support the cable 424. The transfer tower 420 is proximate the loading area 430, while the unloading tower 420 is proximate the unloading area 450. Intermediate the two towers 420, 420 is a plurality of intermediate towers 425. The number of intermediate towers 425 is also a function of the distance between towers 420 and 420 and the loads to be borne by the cable 414.

[0099] FIG. 5 is a schematic view of a transport system 500 of the present invention, in an alternate embodiment. FIG. 5 is provided to demonstrate that a transport system for moving frac sand or other supplies may be networked as between a plurality of well sites.

[0100] First, the transport system 500 includes a first receiving area 530. The first receiving area 530 is designed and configured to receive transfer containers 300. The transfer containers 300 may or may not be pre-loaded with frac sand or other equipment and supplies.

[0101] The transport system 500 next includes a second receiving area 530. The second receiving area 530 is designed and configured to receive transfer containers 300 from the first receiving area 530. The transfer containers 300 are moved from the first receiving area 530 to the second receiving area 530 by means of line 535. When moved across line 535, the transfer containers 300 will be loaded with proppant, water, chemicals or supplies.

[0102] From the second receiving area 530, transfer containers 300 may be moved to either of two selected transfer areas 540, 540. Some selected transfer containers 300 are delivered to transfer area 540 by means of line 535. At the same time, other selected transfer containers 300 are delivered to transfer area 540 by means of line 535.

[0103] Each of transfer areas 540, 540 is configured to receive transfer containers 300, and then hold the boxes 300 for delivery to selected unloading areas 550. In the arrangement of FIG. 5, transfer area 540 serves as a transfer area for the delivery of transfer containers 300 to any of unloading areas 550B, 550C or 550D. Similarly, transfer area 540 serves as a transfer area for the delivery of transfer containers 300 to either of unloading areas 550H or 5501. These transports are made by lines 555.

[0104] It is noted that receiving area 530 may also be used as a transfer area. In this respect, transfer containers 300 may be moved from area 530 directly to an unloading area 550A. This is done via a line 555. Additionally, it is noted that unloading area 540 may also function as a transfer area. Using line 545, transfer containers 300 may be moved to transfer area 540, which then delivers transport boxes 300 to any of selected unloading areas 550E, 550F or 550G.

[0105] Each of lines 535, 535 and 535 represents a first aerial cable conveyance system, indicative of cable conveyance system 235 of FIG. 2. Likewise, each of lines 555 represents an aerial cable conveyance system, indicative of any of cable conveyance systems 242, 244, 246 of FIG. 2.

[0106] Finally, each of the unloading areas 550 is intended to be associated with a well site. The well site may be a single well where completion operations are being conducted. Alternatively, the well site may be a multi-well pad where drilling and completion operations (or downhole well operations generally) are being conducted. Preferably, the completion operations include formation fracturing operations.

[0107] Based on the sand transport systems 200, 400 and 500 described above, a method of using a transport system is provided herein. FIG. 6 is a flow chart showing steps for a method 600 of transporting materials or personnel to well sites, in one embodiment. More specifically, a method for transporting proppant in support of a wellbore operation is provided.

[0108] The method 600 first includes receiving a plurality of transfer containers. This is shown in Box 610. The transfer containers are received at a loading area. In one aspect, each of the transfer containers is delivered to the loading area by means of a truck. Preferably, each of the transfer containers is in modular form, making it movable and stackable using a fork lift. In a preferred embodiment, the transfer containers are pre-loaded with an aggregate such as frac sand. In this instance, the loading area is a sand loading area.

[0109] The method 600 also includes transporting each of the plurality of transfer containers from the loading area to a transfer area. Transport is done in series via a first aerial cable conveyance system. This is shown in Box 620.

[0110] In one aspect, the method 600 also comprises selecting from one of a plurality of second aerial cable systems. This is provided in Box 630. Each of the second aerial cable conveyance systems terminates at a different unloading area. Each unloading area, in turn, is associated with a respective well site.

[0111] The method 600 additionally includes moving each of the transfer containers from the first aerial cable conveyance system to the selected second aerial cable conveyance system. This is indicated at Box 640. This transfer is preferably done using one or more fork lifts, although other conveyance means such as cranes may be used.

[0112] The method 600 then includes transporting each of the plurality of transfer containers from the transfer area to an unloading area, in series. This step is seen in Box 650. The step of Box 650 is done via a selected second aerial cable conveyance system.

[0113] The first and second aerial conveyance systems may be as described above. In this respect, the first aerial cable extends from a first loading tower located at the receiving area to a first transfer tower located at the transfer area. At the same time, the second aerial cable extends from a second transfer tower at the transfer area to an unloading tower at an unloading area.

[0114] Preferably, two or more intermediate towers are placed between the loading tower and the first transfer tower for supporting the transfer containers above ground. Similarly, two or more intermediate towers may be placed between the second transfer tower and the unloading tower for supporting the transfer containers above ground. Preferably, a distance from the loading area to the transfer area is at least one mile (1.61 km), while a distance from the transfer area to a selected unloading area is also at least one mile (1.61 km).

[0115] The method 600 also comprises removing the sand from each of the transfer containers. This is shown at Box 660. The sand (or other contents) is preferably used in connection with a wellbore fracturing operation.

[0116] It is noted that the removal of sand from each of the transfer containers results in a plurality of empty transfer containers at an unloading area. Accordingly, the method 600 may further comprise, following removal of the sand (or other contents) from each of the transfer containers: transporting each of the empty transfer containers from the unloading area back to the transfer area, in series, via the second aerial cable conveyance system; and upon arrival at the transfer area, transporting each of the empty transfer containers from the transfer area back to the loading area, in series, via the first aerial cable conveyance system. In this way, the transfer containers may be recycled.

[0117] As can be seen, an improved method for transporting aggregate in support of a downhole well operation is provided. Although the transport system and the transport methods have been described in the present disclosure primarily with respect to moving frac sand, the system and methods may be used to transport other supplies or personnel in support of wellbore drilling and completion operations. For example, the transfer containers may contain frac chemicals, water/brine, drilling mud, pumps, cleaning supplies, personal supplies for service personnel or frac iron. The transfer containers may be used to transport acid in fluid form in support of a downhole acid treatment operation. In addition, selected transfer containers may be used to transport field personnel.

[0118] It is anticipated that the first and second aerial cables described herein may traverse across farm-to-market roads, county roads, streams, farms and pasture. In some instances, an aerial cable may pass through a town or cross over a freeway, though this is certainly not preferred.

INDUSTRIAL APPLICABILITY

[0119] The systems and methods disclosed herein are applicable to the oil and gas industries.

[0120] It is believed that the disclosure set forth above encompasses multiple distinct inventions with independent utility. While each of these inventions has been disclosed in its preferred form, the specific embodiments thereof as disclosed and illustrated herein are not to be considered in a limiting sense as numerous variations are possible. The subject matter of the inventions includes all novel and non-obvious combinations and subcombinations of the various elements, features, functions, and/or properties disclosed herein. Similarly, where the claims recite a or a first element or the equivalent thereof, such claims should be understood to include incorporation of one or more such elements, neither requiring nor excluding two or more such elements.

[0121] It is believed that the following claims particularly point out certain combinations and subcombinations that are directed to one of the disclosed inventions and are novel and non-obvious. Inventions embodied in other combinations and subcombinations of features, functions, elements, and/or properties may be claimed through amendment of the present claims or presentation of new claims in this or a related application. Such amended or new claims, whether they are directed to a different invention or directed to the same invention, whether different, broader, narrower, or equal in scope to the original claims, are also regarded as included within the subject matter of the inventions of the present disclosure.