Patent Application
20130022441
This document relates to methods and apparatuses for bulk transport of proppant.
Proppant is used in downhole fluid treatments such as fracturing operations, which involve the injection of fluid into the well at pressures sufficient to fracture the formation, followed by the injection of proppant into the fractures to hold the fractures open once the operation is finished.
Conventional transport of proppant from a manufacturer to a well site requires the use of one or more transloading facilities, wherein the proppant is transferred from one type of containment vessel to another. A common example of proppant transloading occurs when a bulk rail car empties a load of proppant into a silo, and the proppant in the silo is subsequently loaded into a pneumatic proppant truck for delivery to a well site.
A method of bulk transport of proppant is disclosed comprising: transporting proppant in an intermodal transport container to a well site, the intermodal transport container having four vertical walls, a roof, and a base, defining an enclosed interior, the proppant being loosely disposed within the enclosed interior; and unloading at least a portion of the proppant through one or more gates in the intermodal transport container at the well site.
An apparatus for bulk transport of proppant is also disclosed comprising: an intermodal transport container at a well site, the intermodal transport container having four vertical walls, a roof, and a base, defining an enclosed interior, proppant being loosely disposed within the enclosed interior; and one or more gates in the intermodal transport container for unloading the proppant.
These and other aspects of the device and method are set out in the claims, which are incorporated here by reference.
Embodiments will now be described with reference to the figures, in which like reference characters denote like elements, by way of example, and in which:
Immaterial modifications may be made to the embodiments described here without departing from what is covered by the claims.
Once loaded in the bulk rail cars, the proppant is transported by rail to a second transloading facility 17, where the proppant is transloaded from the bulk rail cars and placed into storage at the transloading facility 17 in a vertical silo or bin for example. Transloading from the rail car may be carried out by gravity feed from the base of the rail cars onto a conveyor into the facility 17, or by other suitable methods. Once in storage at the facility 17, the proppant is available for pickup by a customer for delivery to the well site. Pickup involves transferring the stored proppant into a proppant truck or tanker. Once loaded, the proppant truck then carries the proppant to the well site 18, where the proppant truck offloads the proppant by pneumatics into a blender or mountain mover for use in a downhole fluid treatment such as a fracturing operation.
The conventional method described above requires a large capital expenditure to acquire and operate the transloading facilities, the warehouse space at the port 14 and each transloading facility, and to acquire and operate the bulk rail cars, the pneumatic proppant trucks, and various other components required to make the system run smoothly. In addition, the complexity and limitations of each transloading stage add weeks and sometimes months to the transport of the proppant to the end user. Moreover, the conventional method requires efficient coordination of the various components in order to minimize delays, which are costly. For example, if facility 17 is not ready to receive the proppant on arrival of the rail cars, even a one to two day sitting period for the rail cars may carry substantial expenses that are passed on to the end user directly or indirectly.
Referring to
The intermodal transport container 30 may further comprise a liner 42, within the enclosed interior 38, that conforms to the four vertical walls 32, the roof 34, and the base 36. The liner 42 may be made of suitable materials such as plastic, and may be reusable. The liner 42 may be affixed, for example with webbing, adhesive, or other suitable mechanisms, to the roof 34 and base 36, and one or more of the walls 32 for stability. The liner 42 in combination with the intermodal transport container 30 may provide weather and moisture protection to the proppant 28. The liner 42 may have a port 44 in an upper portion 46 of the liner 42 for loading proppant 28 into the liner 42. A port 47 in a lower portion 48 of the liner 42 may be provided at a rear end 50 of the intermodal transport container 30 for unloading the proppant 28 from the liner 42. Both ports 44 and 47 may be re-sealable, for example using a zipper 49, ziplock, or other suitable sealing mechanism. Two or more rigid support members, such as steel pipes 52, may span the rear wall 29 in support of the liner 42 when the gates 40 are open. Pipes 52 brace the liner 42 from falling out rear end 50 of the intermodal transport container 30 during tilting of the intermodal transport container 30 as is described in further detail below. The rigid support members (pipes 52) may be oriented at suitable angles, such as horizontal or vertical, and may cross one another to form cross-braces.
Referring to
In a second stage 82 (shown in
The method may further comprise storing the proppant in the intermodal transport container 30 before transporting the proppant to the well site 18. Because the proppant is already safely contained within enclosed interior 38, storage does not require further shelter from the elements, and can be carried out in a suitable location such as a field or warehouse until needed. The intermodal transport container 30 and proppant may also be stored at the well site 18, for example until the well 68 is ready for a fracturing operation. The flexibility and low cost of storage of the intermodal transport container 30 is in contrast with the difficulty and expense associated with storing proppant shipped by the conventional methods described above. Because the intermodal transport container 30 effectively forms a weather protected storage unit, little if any storage infrastructure is required, whereas proppant shipped by the conventional method described above may require silos, bins, transloading equipment, and covered warehouses. In addition, the expense of delay along the supply chain in the conventional method in the form of rail charges, storage fees at transloading sites, and other expenses related to the extra infrastructure required is avoided, with delay in the methods disclosed herein generating only expenses associated with locating and positioning the intermodal transport container 30 at a storage site suitable for container storage.
Referring to
Intermodal transport container 30 transport is also advantageous due to the commonality and low cost of intermodal transport containers 30. Examples of standard intermodal transport containers are illustrated below in Table 1. In some embodiments the intermodal transport container 30 has a standard size of eight feet in width, and twenty, forty, or forty-five feet in length, as containers having these dimensions are common. It should be understood that various other sizes and shapes of intermodal transport containers are envisioned within the scope of this document, and the dimensions illustrated in Table 1 are not intended to be limiting. Further examples of intermodal transport containers include air freight transport containers, which are generally smaller in size from the standard intermodal freight containers used primarily in the rail and ship industries.
A potential disadvantage of the disclosed method over the conventional method described above is infrastructure such as unloading equipment like the proppant transfer device 58, that may be present at the well site 18 in some cases. In addition, transport in an enclosed intermodal transport container 30 may be more expensive than transport in an open-topped proppant dump truck. Moreover, it may be more expensive for the manufacturer 10 itself to ship in lined intermodal transport containers 30. However, despite these potentially higher pinpoint expenses, the disclosed method may still result in an overall cost reduction over the conventional method described above, and the overall benefits in efficiency and speed may outweigh the potential disadvantages. In addition, in embodiments where a proppant transfer device 58 is used that can feed directly to the blender, no mountain mover 64 is required thus potentially reducing instead of increasing on-site expenses.
In the claims, the word “comprising” is used in its inclusive sense and does not exclude other elements being present. The indefinite article “a” before a claim feature does not exclude more than one of the feature being present. Each one of the individual features described here may be used in one or more embodiments and is not, by virtue only of being described here, to be construed as essential to all embodiments as defined by the claims.
| Number | Date | Country | |
|---|---|---|---|
| 61509943 | Jul 2011 | US |
