Patent Application
20120305241
Exploring, drilling and completing hydrocarbon and other wells are generally complicated, time consuming and ultimately very expensive endeavors. In recognition of the potentially enormous expense of well completion, added emphasis has been placed on well monitoring and maintenance throughout the life of the well. That is, placing added emphasis on increasing the life and productivity of a given well may help ensure that the well provides a healthy return on the significant investment involved in its completion. Thus, over the years, well diagnostics and treatment have become more sophisticated and critical facets of managing well operations.
In certain circumstances, well diagnostics takes place on a near-continuous basis such as where pressure, temperature or other sensors are disposed downhole. For example, such sensors may be provided in conjunction with production tubing, laterally disposed frac-liners, chemical injection hardware, or a host of other completions equipment. That is, a monitoring tool with sensors may be affixed downhole with the equipment in order to track well conditions over time. In some cases, the monitoring tools may be fairly sophisticated with capacity to simultaneously track a host of well conditions in real-time. Thus, both sudden production profile changes and more gradual production changes over time may be accurately monitored. Such monitoring allows for informed interventions or other adjustments where appropriate.
In many cases, such called-for adjustments may involve minimal actuations such as the opening or closing of a valve, shifting the position of a sliding sleeve or other similarly low-powered maneuvers. As alluded to above, providing completions equipment outfitted with sensors may avoid the introduction of dramatically more costly logging operations. Thus, by the same token, efforts have been undertaken to outfit completions equipment with affixed tools suitable for achieving minimal actuations such as the noted shifting of a sliding sleeve. So, for example, the costly introduction of a separate coiled tubing intervention dedicated to sliding a sleeve may be avoided.
Providing continuous downhole power to completions equipment may face certain challenges. This is particularly the case where the completions equipment is installed throughout various lateral legs of a multi-lateral well, thereby rendering power supply via conventional electrical cable near impossible. For example, in order to supply a separate electrical cable to each lateral leg of a multi-lateral well, cabling may be dropped through a central bore. This results in separate cable lines exiting the bore into each separate lateral leg. Not only does this present significant installation challenges, the well is left with a myriad of cables running into and out of lateral legs and serving as impediments to follow on applications and/or production itself.
In order to avoid the challenges and obstacles presented as a result of power supply via electric cable, efforts have been made to direct actuation tools via hydraulics. So, for example, it may be possible to direct the shifting of a sliding sleeve in a lateral leg through the hydraulics of the well and/or completions equipment without the need to supply a dedicated electric cable to the vicinity of the sleeve. Of course, such efforts may be fairly sophisticated and lack a degree of reliability. Further, such efforts are impractical in terms of supplying power to monitoring tools. Thus, the effectiveness of the shifting of the sliding sleeve would remain unchecked by any associated nearby monitor.
Given the limitations on hydraulic power as noted above, more discrete and dedicated power supplies have been affixed to completions equipment in hopes of supplying necessary power for low-power monitoring and actuation. For example, completions equipment has been outfitted with lithium-based battery packages adjacent monitoring and/or actuation tools. Thus, in the case of a multi-lateral leg of the well, a monitor or actuation tool therein may be supplied with power directly from the associated battery pack.
The power requirements for the noted monitoring or actuations are small enough to be supplied by the indicated lithium-base batteries. Unfortunately, the life of such lithium-based or other conventionally available batteries is dramatically less than the life of the well. For example, in theory, such batteries may have a life ranging from about 2-3 years whereas the life of the well may be closer to 20 on average. Furthermore, in practice, as the batteries are employed and exposed to high temperature downhole conditions, battery life is even further reduced. As a result, operators may undertake repeated interventions for battery change-outs. Alternatively, repeated logging and actuation interventions may be undertaken with the option of discrete independently powered monitoring and actuation tools foregone altogether. Regardless the particular undertaking selected by the operator, the time and expense involved may be quite dramatic.
A completions assembly is disclosed for installing in a well. The assembly includes one of a sensor and an actuator that is powered by an atomic battery. The battery is equipped for effective supply of power to the mechanisms for an uninterrupted period substantially exceeding about two years.
The noted uninterrupted period may be between about 10 and about 30 years and the atomic battery may be a nano-based beta voltaic battery. Further, a transceiver, transmitter or receiver may also be coupled to the battery to support communications between the mechanisms and equipment at an oilfield accommodating the well.
Embodiments are described with reference to certain downhole completions assemblies. In particular, focus is drawn to assemblies which employ upper or main bore completion portions in conjunction with lower or physically independent completion portions disposed throughout various multi-lateral well legs. However, other types and configurations of completions assemblies may take advantage of the embodiments of tools and techniques detailed herein. For example, completions assemblies of non-multi-lateral architecture and even those lacking a physically independent downhole completion portion may nevertheless utilize tools and techniques detailed herein. Regardless, embodiments of assemblies do include an atomic battery of extended life for powering of certain monitoring and low power actuations over the substantial life of the well.
Referring now to
The structure of the main bore portion 110 includes features for servicing the main bore of the well 180. Namely, production tubing 115 is anchored therein by way of a packer 120 that is sealingly engaged with casing 185 defining the well 180. Similarly, structure of the leg portion 150 includes its own production tubing 116 anchored by production or isolation packers 160, 165, 167 against the uncased wall of the open-hole lateral leg 187. In the embodiment shown, the isolation packers 160, 165, 167 serve to define different production zones 103, 105, 107 of the lateral leg 187. Thus, uptake of production fluids 400 at each zone 103, 105, 107 may be independently achieved through valves 450 (see
Continuing with reference to
The physically independent nature of the separately disposed portions 110, 150 allows for ease of installation and use of the completions assembly 100. Additionally, in the embodiment depicted, this independent nature is further enhanced by the use of wireless telemetry between these portions 110, 150. That is, in addition to avoiding direct tubular connection between the portions 110, 150, use of a physical power and/or data line is also avoided. Such lines may present physical interference and be potentially quite difficult to install. This may be particularly true where the well 180 is multi-lateral in nature and lined power/data telemetry would present a whole host of interweaving physical lines to deal with (see
In the embodiment shown, the absence of power and data lines running all the way to the lateral portion 150 is replaced with a combination of a self-sustained power source (atomic battery 101) integrated into this portion 150 along with wireless communications thereto (note wireless transmission 145). More specifically, the lateral portion 150 is equipped with the noted atomic battery 101 for meeting power requirements and a lower transceiver 140 for wireless communications (with an upper transceiver 130 of the main bore portion 110). As detailed below, the power requirements met by the battery 101 may relate to monitoring, actuating or even the needs of a wireless communication device such as the lower transceiver 140.
The noted communications may be achieved over conventional radio frequency (RF), Bluetooth or other suitable downhole frequencies. Further, depending on the overall configuration and nature of the assembly 100, the transceivers 130, 140 may include any functional variety or combination of wireless communication devices (i.e. transmitters or receivers). For example, in an embodiment limited to monitoring conditions of the lateral leg 150, the lower transceiver 140 may be no more than a transmitter for one way wireless data transmission to a receiver serving as the upper transceiver 130.
More likely, however, each transceiver 130, 140 would be equipped with both conventional transmitters and receivers for two-way short hop wireless communications. Thus, data from sensors 170, 175, 177 monitoring temperature, pressure, flow and other environmental conditions at zones 103, 105, 107 may be carried uphole over a cable 179 to the lower transceiver 140. This data may then be wirelessly transmitted to the upper transceiver 130 (see 145) and ultimately carried over an upper data line 135 to surface equipment for analysis thereat (see
Furthermore, upon analysis of such data, signaling from surface may be supported over this same line 135 such that instructions to the upper transceiver 130 may be wirelessly transmitted back to the lower transceiver 140 (see 145). Such data signal may include actuation instructions directed at a conventional low power downhole actuator 157 which may be configured to responsively open or close certain valves in the production zones 103, 105, 107 based on the noted data analysis (see
As alluded to above, the above described monitoring and actuations which take place at the physically isolated lateral leg portion 150 of the assembly 100 may be powered by an atomic battery 101. More specifically, the atomic battery 101 may be made up of nano-based beta voltaic battery packages as detailed with respect to
By way of example, a hockey puck like 2-5 inch diameter, 5-15 watt nano-based beta voltaic battery may be configured for continuous power drain suitable for monitoring and actuation applications as described above. A battery of this nature may be constructed according to techniques such as those detailed in U.S. Pat. No. 7,663,288 to Chandrashekhar, et al., incorporated by reference herein in its entirety, although other atomic battery construction techniques may also be utilized. Regardless, the need for battery replacement during the life of the well 180 may be avoided due to the atomic nature of the battery 101. Further, in the embodiment shown, a conventional rechargeable or ‘trickle’ charge battery 155 is coupled to the atomic battery 101, further ensuring downhole power reliability and life.
In addition to increased life as compared to, say a conventional lithium ion or polymer battery, the described atomic battery 101 also provides enhanced efficiency. For example, the use of a self-sustained power source at the lower assembly portion 150 means that power losses over potentially several thousand feet of line running from surface are completely avoided. Furthermore, where the atomic battery 101 is of a nano-based beta voltaic variety, power efficiency substantially exceeds about 5%, in contrast to an atomic battery that is of a radioactive theremal generator (RTG) variety.
Referring now to
In
In addition to the upper 130 and lower 140 transceivers referenced in
Regardless of the particular downhole architectural construct, the oilfield 201 is equipped with a variety of surface equipment 210 which may be utilized in carrying out monitoring and actuation applications as noted above. For example, such applications may be carried out in the context of production operations as depicted in
Continuing with reference to
Referring now to
With particular reference to
With added reference to
Referring now to
Referring now to
With particular reference to
Referring now to
As indicated at 545, conditions at the well location of the installed autonomous portion may be monitored by an atomic battery powered sensor thereof. The monitored data may be communicated to surface as noted at 560 in a wireless manner over the referenced surface connected assembly portion. Thus, surface equipment adjacent the well may be utilized to keep track of conditions at the location of the autonomous portion. Indeed, analysis of such data may be performed on a substantially real-time basis (see 575). Furthermore, as indicated at 590, such analysis may even lead to the wireless direction of an actuation at the noted well location, such as the opening or closing of a valve thereat, for example, to affect production therefrom. The atomic battery powered actuator employed may rely on the same atomic battery as that of the sensor as noted above or another more particularly tailored to its own power requirements.
Embodiments described hereinabove include completion assemblies employing stand-alone self-sustaining downhole portions that may be sufficiently powered for certain monitoring and/or actuation applications over the life of the well. This is achieved without the requirement of a cumbersome power or data cable running uninterrupted from surface to the downhole portion. This is also achieved without the requirement of repeated battery change outs. Rather, a practical long-life atomic battery may be incorporated into the independent lower completion portion thereby meeting such power requirements throughout the life of the well.
The preceding description has been presented with reference to presently preferred embodiments. However, other embodiments not detailed hereinabove may be employed. For example, wireless telemetry employed over such completions assemblies may take place outside of the main bore or be acoustic or electromagnetic in nature. Further, the atomic battery may also be utilized in conjunction with storage devices in addition to rechargeable battteries such as capacitors for higher power applications over shorter durations. Indeed, persons skilled in the art and technology to which these embodiments pertain will appreciate that still other alterations and changes in the described structures and methods of operation may be practiced without meaningfully departing from the principle and scope of these embodiments. Furthermore, the foregoing description should not be read as pertaining only to the precise structures described and shown in the accompanying drawings, but rather should be read as consistent with and as support for the following claims, which are to have their fullest and fairest scope.
