Abstract:
A system which may be used to replace workover rigs and metallic pipes for the production of hydrocarbon from wellbores uses a non-metallic, substantially continuous, flexible tube comprising a flexible, non-metallic, e.g. resin-based, substantially continuous production tube that can be wellbore deployed and retrieved without the need of onsite rigs. The system&#39;s components can be placed inside existing pipes for work in old wells where removal of the existing tube is not economical. The tubes may also be spoolable, thereby increasing installation rates and flexibility. Connectors for the tube may be dimensioned and configured to allow for providing and/or sealing downhole tools to the production tube. In certain embodiments, an onsite power generator will provide a clean alternative to existing diesel burning generators and will typically use a furnace, boiler, steam engine and electrical power generator.

Description:
RELATION TO OTHER APPLICATIONS 
     This application claims the benefit of U.S. Provisional Application No. 61/159,589, filed on Mar. 12, 2009. 
    
    
     BACKGROUND OF THE INVENTION 
     Currently, deployment and retrieval of downhole devices such as pumps and production pipes requires a rig, which can be costly. Further, wellbore tubulars tend to be made of metals which may corrode and are rigid, leading to less flexible installation procedures. 
     Over the past 10 years, the application of non-metallic materials in flowlines such as in those used wellbores has proven itself an alternative to metallic flowlines. Metallic materials tend to be less resistant to corrosion and/or chemicals and their rigidity is a factor to be taken into consideration during installation and use. 
     SUMMARY 
     A system is disclosed that uses a non-metallic, substantially continuous, flexible tube comprising a flexible, non-metallic, e.g. resin-based, substantially continuous production tube that can be wellbore deployed and retrieved without the need of on site rigs. Reusability is enhanced since the tube can be retrieved and redeployed in the wellbore. The system&#39;s components can be placed inside existing pipes for work in old wells where removal of the existing tube is not economical. 
     Non-metallic materials such as thermoplastics have high chemical resistance, depending on material chosen, and are typically imperative to corrosion. Tubes comprising such non-metallic materials may also be spoolable, thereby increasing installation rates and flexibility. Such systems may also require fewer personnel and less time to deploy equipment and tube in a well. Systems as claimed herein can be easily insulated for special applications. 
     Connectors for the tube are dimensioned and configured to allow for sealing the downhole tools to the production tube. Additionally, an interface to a tool such as a downhole pump may be provided to allow downhole processes, e.g. dewatering and/or chemical injection. 
     The system may be used to replace workover rigs and metallic pipes for the production of hydrocarbon from wellbores. 
     In certain embodiments, an onsite power generator will provide a clean alternative to existing diesel burning generators and will typically use a furnace, boiler, steam engine and electrical power generator. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The various drawings supplied herein are representative of one or more embodiments of the present inventions. 
         FIG. 1  is a diagram of an exemplary system embodiment; 
         FIGS. 2 and 3  are perspectives in partial cutaway of an exemplary tube illustrating embedded umbilical and/or electrical cables; 
         FIG. 4  is an exemplary plan view of a tube with filters; and 
         FIG. 5  is an exemplary plan view of a tube with deformable material. 
     
    
    
     DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS 
     As used herein, “tube” will be understood by one of ordinary skill in these arts to include a production pipe, an injection pipe, a portion of a tubular to be used within a wellbore, a portion of a tubular to be used within another tubular, or the like. 
     Referring now to  FIG. 1 , rigless intervention and production system  10  comprises flexible, non-metallic, substantially continuous tube  20  and connector  30 . 
     Tube  20  comprises a high temperature tolerant, non-metallic material such as a carbon-enhanced, resin-based thermoplastic, a fluoropolymer, a polyemide material, or the like, or a combination thereof. Kevlar® or other similar materials may be used as part of the tube wall to strengthen tube  20  such as to improve pressure collapse and burst properties. 
     In typical embodiments, a predetermined portion of tube  20  is dimensioned and configured to be deployed within wellbore  100 , with the predetermined portion of tube  20  further comprising first connection end  24  disposed distally from fluid outlet  22 . Tube  20  is typically dimensioned and configured into continuous lengths to reach a desired wellbore depth, typically from around between 6,000 feet to around 10,000 feet. In typical embodiments, tube  20  can withstand a maximum working pressure of around 15,000 psi (1,034 bar). 
     Referring additionally to  FIGS. 2 and 3 , tube  20  may further comprise umbilical  26  and/or electrical cable  27  which may be disposed about a predetermined portion of tube  20 , such as about an interior or exterior surface of tube  20 , or at least partially embedded into tube  20 . In certain configurations, umbilical  26  may further comprise electrical cable  27 . 
     Annulus  28  of tube  20  is typically dimensioned and configured to allow fluids to be pumped into wellbore  100 . 
     Connector  30  is typically attached to first connection end  24  and dimensioned and configured to sealably attach tube  20  to tool  110  which is deployable within wellbore  100 , e.g. pump  110   a  (not specifically shown in the figures), downhole gauge  110   b  (not specifically shown in the figures), sensors  110   c  (not specifically shown in the figures), or the like, or a combination thereof. Tools  100  such as downhole gauge  110   b  may be used to optimize production from wellbore  100 . For example, downhole gauge  110   b  may be dimensioned and configured to measure pressure of injected water near the bottom of wellbore  100 , temperature of injected water near the bottom of wellbore  100 , or the like, or a combination thereof. As used herein, “wellbore” and “well” may be used synonymously, as the context requires. 
     Sensors  110   c  may be embedded into tube  20  such as during the manufacturing process. These sensors  110   c  may comprise induction system sensors for formation evaluation and fluid evaluation; radio frequency identification sensors (RFID); pressure and temperature sensors, or the like, or combinations thereof. Sensors  110   c  may be operatively connected to cable  27 , e.g. using wired or wireless connections, umbilical  26 , or to a cable disposed outside tube  20 . Fiber wire  28  may also be embedded or otherwise disposed inside tube  20  and used for sensing downhole data such as data regarding production status, fluid configuration, fluid flow, fluid density, microseismic data, strain, pressure, temperature, or the like, or a combination thereof. As will be apparent to one of ordinary skill in these arts, sensor  110   c  may be a plurality of sensors  110   c  embedded at a corresponding plurality of locations in tube  20  or gathered into less than a corresponding plurality of locations in tube  20 . Sensors  110   c  may further comprise one or more coils dimensioned and configured to provide formation evaluation data, data communications, or the like, or a combination thereof. 
     In certain embodiments, tube spooler  40  is operatively connected to tube  20 , i.e. tube  20  may be spooled and/or unspooled from tube spooler  40 . Tube spooler  40  may comprise a power cable spooler or a combination of a power cable and a tube spooler. 
     Vehicle  130  may be part of rigless intervention and production system  10  and dimensioned and configured to accept tube spooler  40 . One or more tube spoolers  40  and/or power cable spoolers may be located in the same unit for deployment, e.g. vehicle  130 . 
     In currently contemplated embodiments, vehicle  130  comprises mast  132  and controller  134 . Controller  134  is operatively in communication with tube spooler  40 . Controller  134  controls the tension on tube  20 , depth of tube  20  into wellbore  100 , as well as control the starting and stopping of tube spooler  40 . Controller  134  may be an electro-hydraulic controller, an electronic controller, or the like, or a combination thereof. 
     Rigless intervention and production system  10  may further comprise power generator  50 . Typically, power generator  50  is a steam-powered electricity generator disposed at or near a surface location of wellbore  100 . Power generator  50  may be in fluid connection with fluid outlet  22  to allow use of water from wellbore  100  obtained through fluid outlet  22  to be turned into steam to provide power for power generator  50 . In currently envisioned embodiments, power generator  50  may be dimensioned and configured to use natural gas to generate heat to boil the water into steam for use by power generator  50 . The water and natural gas may be obtained from wellbore  100 , transported from a remote location, or the like, or a combination thereof. 
     Injector  60  may be present and operatively in fluid communication with tube  20  and used at wellhead  102  for the deployment of the system in wellbore  100 . In these embodiments, injector  60  is dimensioned and configured for injection of fluids into wellbore  100  from the surface through a predetermined portion of tube  20 . These fluids are typically usable for water injection suitable for well desalination or chemical injection. 
     Tube stop  120 , which may include devices such as packers, may be deployed in wellbore  100  to secure tube  20  to a predetermined location in wellbore  100 , such as near well perforations. 
     In further embodiments, a tool such as packoff unit  136  or tube hanger (not shown in the figures) is dimensioned and adapted to secure tube  20  inside wellbore  100  near wellhead  102 . Tool  136  would typically be attached to the casing wall. 
     In certain embodiments, tube  20  further comprises a material disposed about an outer surface of tube  20 . This material may be disposed along one or more predetermined lengths of tube  20  that match predetermined geological zone  104  in wellbore  100  that needs to be isolated. The material is configured and adapted to swell when in contact with a fluid, such as hydrocarbon or other fluids such as water, such that the material swells and seals the area between the outside of flexible non-metallic continuous tube  20  and well casing  104  or a geological formation when the material gets in contact with the activating fluid. For embodiments where the geographical zone comprises a plurality of zones in wellbore  100 , the material may be disposed along different lengths of tube  20  where each such length matches one of the geological zones. This configuration can be used to isolate a zone in wellbore  100  where metallic production tube may be leaking. In this case, tube  20  can be deployed through the production tube and the production would then continue through tube  20  as opposed to the original production tube. 
     By way of example and not limitation, in certain embodiments, isolation material such as rubber formation isolation material can be attached to packoff unit  136 , tube  20 , or both, either permanently or removably. This material may be swell when in contact with a fluid, such as hydrocarbon or other fluids such as water, such that the material swells and seals the area between the outside of flexible non-metallic continuous tube  20  and well casing  104  or a geological formation when the material gets in contact with the activating fluid. 
     In the operation of preferred embodiments, rigless intervention and production system  10  may be used for wellbore operations. 
     In one exemplary embodiment, rigless intervention and production system  10  is used for dewatering by deploying a predetermined portion of a flexible, non-metallic, substantially continuous tube  20  within wellbore  100 ; attaching first connection end  24  to pump  110   a ; and using pump  110   a  to introduce water from wellbore  100  into an annulus of tube  20 . Pump  110   a  may be attached to first connection end  24  prior to deploying tube  20  and pump  110   a  into wellbore  100 . 
     In a further exemplary embodiment, power generator  50 , which is in fluid communication with the annulus of tube  20 , may be used to generate electricity using water introduced to power generator  50  via tube  20 . 
     Once so deployed, production of hydrocarbons through the annulus of tube  20  may be allowed. Further, water or chemicals may be injected into wellbore  100  through tube  20 . 
     Referring additionally to  FIG. 4 , in certain contemplated embodiments, control of sand or other particulate matter within wellbore  100  may be accomplished using tube  20  or a portion of tube  20 . A control depth of a production pipe within wellbore  100  is determined, where the control depth may be the result of sand or other unwanted solids being present. In these embodiments, tube  20  is fashioned with one or more filters  21  disposed at a predetermined length of tube  20  and then tube  20  deployed into wellbore  100 . Filters  21  are dimensioned and adapted to filter a solid such as sand from fluid being produced in wellbore  100 . Deploying tube  20  to the control depth positions filter  21  in wellbore  100  at the control depth production of the fluid is the allowed through filter  21 , such as into tube  20 . Tube  20  with filter  21  may also be a standalone unit deployed with standard metallic pipe. 
     Referring additionally to  FIG. 5 , in certain contemplated embodiments, tube  20  may further comprise deformable material  23 . By way of example and not limitation, piezoelectric material can be molded onto tube  20 , which itself may comprise a suitable plastic, and deformed to allow or impede the flow of hydrocarbons into tube  20  when electrical current is exerted onto the material. The piezoelectric material may be enhanced with nanotubes dimensioned and configured to control the flow of fluids being produced in wellbore  100 . Tube  20  with deformable material  23  may also be a standalone unit deployed with standard metallic pipe. 
     The foregoing disclosure and description of the inventions are illustrative and explanatory. Various changes in the size, shape, and materials, as well as in the details of the illustrative construction and/or a illustrative method may be made without departing from the spirit of the invention.