Patent Application
20100000740
This section is intended to introduce the reader to various aspects of art, which may be associated with exemplary embodiments of the present invention, which are described and/or claimed below. This discussion is believed to be helpful in providing the reader with information to facilitate a better understanding of particular aspects of the present invention. Accordingly, it should be understood that these statements are to be read in this light, and not necessarily as admissions of prior art.
The production of hydrocarbons, such as oil and gas, has been performed for numerous years. To produce these hydrocarbons from a subsurface formation or basin, one or more wells may be distributed above the subsurface formation to provide access to the subsurface formation. In the wells, tools and equipment, which are generally installed into a well during a completion phase, are utilized to produce hydrocarbons from the wells. In this phase, the tools and equipment are actively utilized to manage the flow of hydrocarbons from the subsurface formation to the surface. Accordingly, by utilizing these tools and equipment, companies produce hydrocarbons from the reserves in the subsurface formations. Further, it may also be desirable to inject water, treatment fluids, or other materials into the well utilizing the tools and equipment indicated above in the completion phase.
As the demand for hydrocarbons continues to grow, additional challenges are encountered in developing subsurface formations. For instance, to produce hydrocarbons from some subsurface formations, long-interval completions and/or multilateral technology may be utilized to provide access to multiple subsurface formations with a single well. The use of a long-interval completion may reduce development costs and justify access to certain subsurface formations. In particular, the long-interval completion may justify access to subsurface formations located in remote areas or in deepwater environments.
However, wells with long, multiple-interval completions typically encounter a number of technical issues that may limit or stop production of the hydrocarbons from the subsurface formation. That is, the extended depth of these wells increases the probability of encountering multiple technical issues, while operating the well over a period of time. These technical issues may reduce productivity, cause mechanical damage to the subsurface/surface equipment, or end production for the well.
If data is available, these specific technical issues may be compensated for in the design and planning phases. With this approach, each technical issue is typically addressed individually. Unfortunately, the personnel designing a completion may require accurate data to address the technical issues that may be encountered over the life of the well. The lack of data and/or uncertainties in the accuracy of the data precludes reliable predictions, often resulting in completion designs that limit production or require repeated interventions or workovers to maintain a certain level of production. That is, typical well completions can not react to problems encountered during its operation, which results in relying on a well strategy that utilizes remedial interventions or workovers to address problems with the well.
Some techniques related to designing completion architectures have been disclosed. For example, U.S. Patent Application No. 2002/0177955 discloses a method and apparatus for performing well planning and “general-level” design such as well depth, angle, position, divergence, etc. The patent also discloses use of inflow control devices and valves to allow operator intervention if an event such as a gas breakthrough should occur. However, the patent fails to disclose the use of technologies that proactively address wellbore issues by remaining dormant until needed and fails to teach the selection and use of a variety of wellbore technologies to address the plurality of technical issues that can and do arise in well completions.
Accordingly, the need exists for a method or mechanism that may enhance the operation of a well by handling multiple technical issues concurrently, while reducing potential interventions and workovers. Also, the method or mechanism may be proactive instead of reactive by installing technology in the completion initially to enable an automated or instantaneous response to technical issues during the operation of the well.
In one embodiment, a method of completing a well is disclosed. The method includes identifying technical issues associated with a well. Then, a technology is selected for each identified technical issue to address at least one of the technical issues. Further, a set of criteria is defined for each selected technology to determine when to employ the selected technology in the well because each selected technology may remain dormant until the set of criteria are met. Finally, the technologies are integrated into a well completion profile and utilized in the deployment of the technologies into the well to produce hydrocarbons. Some of the technical issues include: the presence of water in the wellbore, formation of a sand bridge, rupture of a primary sand screen, and the presence of hydrocarbons in the well. The well may be a producing well or an injection well.
In a second embodiment, a method of completing a well is disclosed. The method includes identifying at least three technical issues associated with a well; identifying at least three technologies, wherein each of the technologies addresses at least one of the technical issues; defining criteria for each of the technologies to determine when to employ the specific technology in the well; and integrating the technologies into a well completion profile for the deployment of the technologies into the well, wherein at least one of the technologies remains dormant until the criteria is met for that specific technology. The well may be a producing well or an injection well.
In a third embodiment, a method of producing hydrocarbons is disclosed. The method includes identifying technical issues associated with a well; determining one or more technologies to address each technical issue; creating a well completion profile that includes the technologies to address the plurality of technical issues; and producing hydrocarbons from the well based on the well completion profile. The well completion profile may be stored in the memory of a processor based device.
The foregoing and other advantages of the present technique may become apparent upon reading the following detailed description and upon reference to the drawings in which:
In the following detailed description, the specific embodiments of the present invention will be described in connection with its preferred embodiments. However, to the extent that the following description is specific to a particular embodiment or a particular use of the present techniques, this is intended to be illustrative only and merely provides a concise description of the exemplary embodiments. Accordingly, the invention is not limited to the specific embodiments described below, but rather, the invention includes all alternatives, modifications, and equivalents falling within the true scope of the appended claims.
Some embodiments of the present techniques relate to a method and mechanism for enhancing hydrocarbon well completions to facilitate well operations. Well operations may include production of hydrocarbons, injection operations, and other activities known to those of skill in the art. Under some aspects of the present techniques, the design of a completion configuration is managed as a well completion profile that accounts for potential technical issues in the producing environment during the life of the well. That is, the well completion profile is utilized to enhance production, injection, or other activities by designing the well completion to account for various technical issues expected to impact these activities. Accordingly, tools may be deployed into a well and remain dormant until specific events activate the tools. The tools provide a flexible mechanism for managing the well on a foot-per-foot basis. As a result of this proactive method, interventions and workovers may be reduced to enhance the operation of the well.
The present techniques, may utilize different types of well completions, such as an open-hole completion or a cased-hole completion, to access a subsurface formation. With a cased-hole completion, a production casing string is set adjacent to the subsurface formation. Then, the production casing string is perforated to provide a fluid flow path from the subsurface formation to the production casing string. The production casing string supports the walls of the wellbore and controls the flow of fluids through specific perforations. Alternatively, with an open-hole completion, no production casing string is placed adjacent to the subsurface formation. As a result, the open-hole completion may experience more technical issues because it does not provide same level of fluid inflow control and wellbore support as a cased-hole completion. Accordingly, to clarify aspects of the present techniques, an open-hole completion is utilized for exemplary purposes, as discussed below in
Turning now to the drawings, and referring initially to
Various casing strings may be installed into the wellbore 102 to provide access to the subsurface formation 106. For example, a surface casing string 120 may be installed from the surface 104 to a specific location beneath the surface 104. Within the surface casing string 120, an intermediate or production casing string 122 may be utilized to provide support for walls of the wellbore 102. The production casing string 122 may extend down to a depth near the subsurface formation 106. The surface and production casing strings 120 and 122 may be cemented into a fixed position within the wellbore 102 to provide further support.
In some embodiments of the present techniques, equipment and tools may be connected from the surface 104 to positions near the subsurface formation 106. As an example, the well 100 may include a tree 124 located over the wellbore 102 at the surface 104. The tree 124 may be coupled to various tools 126a-126d via a production tubing or workstring 128 and a control cable 130. The production tubing 128 may extend through the tools 126 or be coupled to specific tools 126. This connectivity may be based upon the specific configuration of the tools 126 utilized in the wellbore 102. Similarly, the control cable 130 may be connected to one or more of the tools 126 to provide control signals and sensory data to monitoring equipment (not shown) that tracks the conditions within the wellbore 102.
Other equipment may also be utilized to manage various zones within the wellbore 102. For instance, packers, such as packer 136, may be utilized to isolate the wellbore annulus from other zones within the wellbore 102. In a similar manner, a safety valve 132 may also be utilized to block the flow of fluid from a specific point to the surface 104. In particular, the safety valve 132 may be utilized to prevent the abnormal flow of fluids from reaching the surface 104. That is, the safety valve 132 may control the flow of fluids in the production tubing 128, while being controlled by sensors (not shown) or the control cable 130.
Because open-hole completions generally have higher production rates with lower drilling and completion costs, these types of completions are frequently utilized to develop subsurface formations. However, the open-hole completions are not designed to concurrently manage multiple technical issues that the well could face over its lifetime. Generally, the technical issues of open-hole completions are addressed when they occur through remedial actions, such as a workover or intervention, and are not proactively evaluated to determine technical solutions for potential technical issues that may be encountered concurrently.
The problem with open-hole completions is further compounded by accessing subsurface formations with a long-interval completion. As noted above, these well completions typically encounter multiple technical issues because of the length and complexity of the completion. Unlike short single zone/single interval completions, long-interval completions may access multiple hydrocarbon zones with a single well, such as well 100. Because of its length or complex geology, the long-interval completions may encounter multiple technical issues that limit production rates and/or lead to numerous interventions/workovers over the lifetime of the well. The technical issues present in a long-interval completion may include sand production, early water breakthrough, early gas breakthrough, cross flow and/or other similar problems. As a result, the well may have productivity reduced, mechanical damage to the subsurface/surface equipment, and/or a loss of production.
For example, the well 100 may produce sand during its operation. The sand production may result in subsurface equipment damage, fill-ins or cave-ins of the wellbore 102. As a result, remedial action, such as a workover or intervention, may be performed to clean out the well before production from the subsurface formation 106 is resumed. This problem is further complicated with the well being in a remote location, such as a deep-water environment or remote location, which also increases the cost of the remedial actions.
Further, the remedial actions may only provide a partial solution to the technical issue. For example, in addition to sand production, a well may experience water breakthrough in the well. The water breakthrough may result in another remedial action to plug the interval or zone that is producing water. This remedial action may include setting a bridge plug inside a sand screen within the wellbore 102. However, this bridge plug may simply slow down the water from the problem zone because the wellbore annulus remains in communication with the water producing zone, if the annulus has not collapsed. If the trouble zones can not be controlled or shut-off, the well's productivity is compromised because the equipment on the surface may be limited by the amount of water, gas or sand that it can process. In this situation, the excess sand may damage equipment, while excess water may make the well non-economical because the oil production may have to be reduced. As such, sand production and water breakthrough in an open-hole completion may result in two or more interventions to resolve the problem or may even result in the abandonment of the well.
As another approach to managing technical issues within a portion of the wellbore 102, flow control valves and zonal isolation devices may be utilized to manage the flow of unwanted fluids from a specific zone. These devices provide large or “macro scale” control of water or gas by shutting off or limiting the water of gas from the appropriate zones. That is, the flow control valves and zonal isolation devices block an entire zone to prevent the flow of the water or gas from that zone or limit the flow of water or gas from that zone. As a result, the oil or gas from those specific zones of the subsurface formation may be lost or production may be severely limited.
To address these different issues, the present techniques provide a mechanism that proactively adapts the well completion profile to address multiple technical issues without operator intervention, as discussed in greater detail in
The flow chart begins at block 202. At block 204, technical issues that are predicted or expected to be present are identified. The identification of technical issues may be based on sample well cores that are provided from the wellbore 102, modeling tools, similar experiences with other wells, or a combination of these techniques. The identified technical issues may include gravel placement, reliable screen running, water or gas breakthrough, screen reliability, flow impairment, flow control, zonal isolation, and/or intervention. With the technical issues identified, a well completion profile may be created, as shown in block 206.
The well completion profile may include selecting one or more technologies to address each of the technical issues It should be noted that one or more technologies may be available to address a technical issue. “Technical issues” are problems that are specific in nature, but include uncertainty as to their timing, location and magnitude during the lifetime of a well. Technical issues can generally be addressed by a particular apparatus, system, or process, called a “technology.” Examples of technologies that address technical issues are shown below in Table 1.
From the available technologies of Table 1, one or more technologies may be selected as part of the well completion profile, which is discussed further in
In blocks 208 and 210, the various technical solutions of the well completion profile may be deployed to produce the hydrocarbons from the well. At block 208, the selected technologies that represent the technical solutions may be deployed into specific locations of the wellbore. Then, at least some of the selected technologies may be utilized to produce hydrocarbons from the well, as shown in block 210. Accordingly, the process ends at block 212.
Beneficially, the present techniques provide a proactive mechanism to address multiple technical issues without operator intervention. In the present techniques, the design of a completion is configured to proactively adapt the well completion profile to changes in the producing environment, such as geologic/reservoir uncertainties such as early water or gas breakthrough, for example. That is, the well completion profile may be developed to integrate various technologies to address technical issues during the installation of, design of, and production from the well completion. By managing the production of hydrocarbons from the subsurface formation 106 as a well completion profile, interventions and workovers may be reduced or eliminated for the well. However, it should be noted that the present techniques are fully compatible with standard intervention techniques known to those of skill in the art, such as, for example, a subsea intervention module (SIM), some embodiments of which are disclosed in U.S. Pat. No. 6,488,093.
Further, as noted in Table 1, the selected technologies may either be active or remain dormant until certain criteria are met to active the technology. That is, tools, which incorporate the technologies, may be deployed into or adjacent to the wellbore 102 to provide selected technologies that address specific technical issues expected or predicted to occur during the life of the well. Some of these technologies may be active technologies that perform the specific function that they are designed to perform. As an example of active technologies, an inflow control device is an active technology because it manages the flow of fluids regardless of its settings or configuration. Also, a safety valve is an active technology that operates in multiple configurations and performs its specific function when it is installed.
However, some of the tools may be dormant because the tools include technologies that remain inactive or dormant until certain criteria are met, as noted above. For example, redundant screening is a technology that remains dormant because the redundant sand screens are not actively filtering sand from the fluids within the wellbore. The technology becomes active only when the primary sand screen is ruptured or damaged and the redundant screens are utilized to filter sand from the subsurface formation fluids. Similarly, for the alternate path technology, shunt tubes are not utilized until a bridge is formed forcing the fluid to flow through the shunt tubes to access the annulus space below the bridge that is not packed with sand or gravel. As such, the shunt tubes remain dormant until pressure increases to force the fluid to flow through the shunt tubes. The creation of the flexible well completion profile is further explained in
The flow chart begins at block 302. In blocks 304-310, a first technical issue may be addressed by a selected technology. At block 304, a first technical issue is identified in a manner similar to the block 204 of
As shown in blocks 312-316, another technical issue may be analyzed, which is similar to the discussion of blocks 304-310 above. In block 312, another technical issue may be identified. Then, one or more technologies may be identified to address the technical issue in block 314. At block 316, another technology is selected to address the technical issue.
At block 318, the previously selected technologies are compared to the currently selected technology for the other technical issue to determine if the technologies are compatible. The previously selected technologies may be the first technology, other technologies previously selected in this process, or other technologies installed within the wellbore. That is, some technologies may not be designed to Interact with each other. As a specific example in open-hole gravel pack completion, use of a conventional packer for zone isolation may be unsuitable with external shunt screen due to its complex geometry. Accordingly, modifications of the technologies may be performed to ensure a compatible and reliable design. If the technologies are incompatible, then another technology is selected in block 316. However, if the technologies are compatible, then the criteria to activate the selected technology is established in block 320, which may be similar to the discussion of block 310.
Once another technology has been selected for the other technical issue, a determination is made if other technical issues are to be addressed, as shown in block 322. If another technical issue is to be addressed, then another technical issue is identified in block 312. However, if no other technical issues are to be addressed, the flexible well completion profile may be saved, as shown in block 324. The saving of the flexible well completion profile may include storing the well completion profile in the memory of a processor-based system, such as computer system or database, for example. Accordingly, the process ends at block 326.
Based on the selected technologies in the flexible well completion profile, various combinations of technologies may be integrated together to address any number of technical issues for a well completion. These selected technologies may be integrated, on a case-by-case basis, to design a well completion that enhances productivity, while reducing the potential for interventions or workovers by an operator. That is, the flexible well completion manages the production of hydrocarbons as a well completion profile rather than a single event or issue during the life of the well. Accordingly, because of the flexibility of the well completion profile, the potential number of configurations that may be utilized together is limited by available technologies.
As a general example, several technologies may be combined based on the technical issues to be addressed in the well completion. These various configurations are shown below in Table 2 for a well completion.
As shown in Table 2, a flexible well concept may include various technical issues to be addressed. Based on the technical issues, different technologies, which are referenced by technology reference numbers of Table 1, are selected to be included as part of the well completion profile. Accordingly, these exemplary configurations integrate the technologies to manage the production of hydrocarbons in an efficient manner from the well.
As a specific example, during the design phase, sand control, shale instability, screen erosion, flow impairment from filtercake and water breakthrough may be the technical issues identified for the well. Based on these technical issues, the associated technologies may include alternate path, completion packing process, redundant screening, filtercake removal process, swellable polymers and swellable packer. Of these selected technologies, alternate paths, redundant screening device, swellable polymer and swellable packer are dormant technologies, while the completion packing process and filtercake removal process are active technologies utilized within the well.
Advantageously, the flexible completion profile does not require precise knowledge of the technical issues, such as the location and specific details about the technical issue. Indeed, the adaptive nature of the flexible well completion utilizes the selected technologies, when certain criteria are met. That is, the selected technology may remain dormant, until an event satisfies the criteria established for the selected technology. As a result, remedial activities, such as workovers and interventions, may be reduced or eliminated for the specific well.
Further, the present technique provides a flexible mechanism for managing a well in specific portions of a zone, instead of the entire zone. For instance, the present technique may block portions of a zone that is producing water or gas, while retaining the capability to produce oil within the remaining portions of the zone. This functionality may be provided by utilizing a technology, such as swellable polymers, for example, that activate automatically based on certain criteria being detected or present within the wellbore 102. In this manner, the reserves from the zone may be recovered, while preventing or reducing the production of water or gas. Exemplary embodiments of a well completion based on the well completion profile is discussed in greater detail in
In
The alternate path technology is deployed within the wellbore 102 as part of the tools 402a, 402b, and 402c, which may be collectively referred to as tools 402. As noted above in Table 1, the alternate path technology includes external or internal shunt tubes adjacent to sand screen to provide a redundant path for slurry to bypass annular bridges. Each of the tools 402 includes a shunt pipe 410 with different nozzles, such as nozzles 412a, 412b and 412c. During gravel pack placement, the tools 402 may remain dormant when the fluid, such as gravel slurry, flows through the annulus between the screens 404a-404b and the walls of the wellbore 102, the tools 402 may be activated by the formation of a sand bridge in the annulus that forces the gravel slurry through the shunt pipe 410 and nozzles 412a, 412b and 412c. As such, the tools 402 may include a dormant technology that is placed within a well completion, but not utilized until sand bridges are formed within the wellbore 102.
Another technology that may be deployed into the wellbore 102 may be redundant screening technology. The redundant screening technology addresses sand screen reliability issues and may be deployed as redundant screens within tools 404a and 404b, which may be collectively referred to as tools 404. Again, as noted above in Table 1, the tools 404 provide redundant sand screens to improve reliability and longevity of sand filtering screens that may be damaged by erosion. Each of the tools 404 include a first sand screen 414 adjacent to the walls of the wellbore 102 and a second sand screen 416 along the flow path 418 from the first sand screen 414 to the production tubing 128. With this technology, the first sand screen 414 is active because it prevents sand from flowing into the production tubing 128, but the second sand screen 416 is dormant because it is not actively filtering sand from the fluids entering the wellbore 102. However, the second sand screen 416 may automatically become active when a failure, such as a puncture or rupture of the first sand screen 414 occurs. Thus, the tools 404 may be a dormant technology placed within a well completion, but not utilized until a specific event, such as a rupture of the first sand screen 414 has occurred.
The final technologies utilized In this embodiment are swellable polymers along with an inflow control device in a tool 406. In this tool 406, the swellable polymer technology addresses water breakthrough issues, while the inflow control device may be adjusted to manage the flow of fluids through the tool 406 into the production tubing 128. This tool 406 has a sleeve 428 with an opening that engages with different ports 422, 424 and 426 to manage the flow of fluids from the zone 116. Based on the location of the sleeve 428 relative to the port 422, 424 and 426, different configurations or settings may control the amount of fluid that enters the tool 406. For instance, in an open configuration, the sleeve 428 may permit fluid to flow through the port 422. In a choked or restricted configuration, the sleeve 428 may permit fluids to flow through the port 424. In a closed configuration, the sleeve 428 may prevent the flow of fluids to the production tubing 128. The sleeve 428 may be adjusted to the various ports 422, 424 and 426 based on a comparison of a value determined from monitors or sensors associated with the wellbore and a predetermined or set value. In addition to the sleeve 428 and ports 422, 424 and 426 of the inflow control device, a polymer may be disposed adjacent to the ports 422, 424 and 426 to swell on contact with water. This polymer may be utilized to provide a water shut-off functionality to the tool 406. As such, the tool 406 utilizes technology that remains dormant until water is detected in the wellbore 102.
As an additional technology, the swellable packer technology may be deployed into the wellbore 102 as a first swellable packer 502 and a second swellable packer 504. The swellable packers 502 and 504 are utilized along with the tools 402, 404 and 406 to divide the completion interval into different production sections, which may correspond to the zones 108, 112 and 116. As noted above in Table 1, the swellable packers 502 and 504 expand on contact with hydrocarbons and provide annular isolation for open-hole completions. In this example, the swellable packer 502 along with the production packer 136 isolate the fluids in zone 108 to force the fluids to follow the fluid flow path 418. The swellable packers 502 and 504 isolate the fluids in zone 112 to force the fluids to follow the fluid flow path 506. Finally, the swellable packer 504 forces the fluids in zone 116 to follow the fluid flow path 420. Because the swellable packers 502 and 504 do not expand until the hydrocarbons contact the swellable packers 502 and 504, they may be considered a dormant technology that is placed within a well completion, but not utilized until hydrocarbons are present.
It should also be noted that a well completion profile may be developed to address the technical issues facing a cased-hole completion under the present techniques. For instance, the well completion profile may include gravel pack along with other technologies to address technical issues associated with a well. The creation of the well completion profile may be performed in a similar manner to the discussion above relating to open-hole completion. It should be appreciated that the selection, integration and deployment of technologies within the cased-hole well may be different from the use of these technologies within an open-hole completion. Regardless, the well completion profile may be utilized to proactively address technical issues to reduce workovers and interventions for a well.
While the present techniques of the invention may be susceptible to various modifications and alternative forms, the exemplary embodiments discussed above have been shown by way of example. However, it should again be understood that the invention is not intended to be limited to the particular embodiments disclosed herein. Indeed, the present techniques of the invention are to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention as defined by the following appended claims.
This application claims the benefit of U.S. Provisional Application No. 60/772,067, filed 10 Feb. 2006.
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/US07/00536 | 1/9/2007 | WO | 00 | 4/14/2009 |
| Number | Date | Country | |
|---|---|---|---|
| 60772067 | Feb 2006 | US |
