Patent Abstract:
A method to produce formation fluid from an oil or gas well. The methods employs a jet pump and a spoolable multi-string tubing system. The jet pump is adapted to produce formation fluid, which may be produced in combination with power fluid. The multi-string tubing system consists of two or more tubing conduits, allowing surface pump equipment to deliver power fluid to the jet pump down a supply tubing string, while return fluid is returned up a return tubing string. Other downhole functions can be provided with the inclusion of additional features on the jet pump and additional conduits or conductors in the multi-string tubing system. Preferred embodiments provide additional functionality by inclusion of a jetting sub, sensing elements, or a back-pressure valve to the jet pump, and auxiliary tubing strings or communication members to the spoolable multi-string tubing system.

Full Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of priority of U.S. Provisional Patent Application No. 61/181,209 filed May 26, 2009, which is incorporated herein by reference in its entirety. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates generally to jet pumps. More particularly, the present invention relates use of jet pumps for fluid production. 
     BACKGROUND OF THE INVENTION 
     Various types of formation fluid recovery systems have been devised for moving fluid from a downhole hydrocarbon formation to the surface. Common fluid recovery systems are beam pumps, progressive cavity pumps electric submersible pumps and gas lift systems. All of the above have operational issues which can limit their performance and application. Jet pumps are useful in a wide range of well applications. Nonetheless, jetpumps for use in hydrocarbon production are a relatively underdeveloped technology. 
     To date, jet pump systems have been installed using either conventional jointed tubing or conventional coiled tubing. In some of these installations, the process requires that there be two strings installed in the well. Where two strings are used, they are most typically configured as a tubing string inside of a tubing string, or a concentric configuration. In most of these applications the tubing systems are not adapted for rapid deployment and retrieval. 
     There are operational and technical advantages to configuring the system with two or more substantially parallel tubing strings or electrical conductors. However, until recently significant practical problems with this approach had not been addressed. The present invention provides a bundled tubing system which is readily deployed and installed in a wellbore using a single conventional coiled tubing unit. Combining this system with a jet pump facilitates a broad range of applications, for example production of hydrocarbons from a hydrocarbon bearing formation. 
     The abstract of U.S. Pat. No. 5,033,545 reads as follows: “The device employs the jet pump principle to bring a power fluid to sedimented solids and the like plugging a conduit, and it includes at least one nozzle which directs the power fluid in a high-velocity jet against the solids to bring the solids into suspension for subsequent removal thereof using the jet pump principle.” 
     The abstract of U.S. Pat. No. 5,372,190 reads as follows: “A down hole jet pump having various unique features which enables the pump to be used with various types of producing wells including those which produce gas along with a large ratio of water which may include considerable abrasive solid materials and can be run and retrieved inside coil tubing of relative small diameter as well as conventional threaded pipe of relatively small diameter. The embodiments of the jet pump disclosed enable the components of the jet pump to be retrieved by reversal to enable removal, replacement or adjusted to provide optimum operation of the pump in accordance with the installation requirements without the use of special tools.” 
     Concentric completion may require that a service rig first run an outer string and then run an inner string. The inner string may be a jointed string or a string of coiled tubing. In either case a considerable amount of time is required for installing the concentric strings; equipment and operating costs can therefore be significant. Similarly, if the downhole equipment must be retrieved, concentric tubing may increase the time required for retrieval of the downhole equipment. 
     It is, therefore, desirable to provide a system and method for multi-string tubing jet pump system for fluid production. 
     SUMMARY OF THE INVENTION 
     It is an object of the present invention to obviate or mitigate at least one disadvantage of previous systems and methods for multi-string tubing jet pump system for fluid production. 
     In a first aspect, the present invention provides a method of producing formation fluid from a hydrocarbon bearing formation including:
         providing a jet pump having a jet pump intake, a venturi nozzle, a venturi gap, a diffuser, and a jetting sub;   deploying the jet pump into a wellbore;   supplying power fluid to the jet pump via a supply tubing string; and   receiving return fluid from the jet pump via a return tubing string.       

     In a further aspect, the present invention provides a method of producing formation fluid from a hydrocarbon bearing formation including:
         providing a spoolable multi-string tubing system having two or more conduits laterally disposed with respect to one another, the two or more conduits comprising a supply tubing string and a return tubing string;   providing a jet pump having a power fluid inlet; a jet pump intake, a venturi nozzle, a venturi gap, and a diffuser in fluid communication with the power fluid inlet; a return tube in fluid communication with the diffuser; and a return fluid outlet in fluid communication with the return tube; wherein the power fluid inlet and the return fluid outlet are laterally disposed with respect to one another to facilitate connection of the power fluid inlet to the supply tubing string and of the return fluid outlet to the return tubing string;   establishing fluid communication between the two or more conduits and the jet pump at the power fluid inlet and the return fluid outlet;   deploying the jet pump into a wellbore;   supplying power fluid to the jet pump via a supply tubing string; and   receiving return fluid from the jet pump via a return tubing string.       

     In an embodiment, the present invention provides a method of producing formation fluid from a hydrocarbon bearing formation wherein the jet pump further includes a jetting sub, and further including flowing jetting fluid out of the jetting sub. 
     In an embodiment, the present invention provides a method of producing formation fluid from a hydrocarbon bearing formation wherein the jet pump further includes a jetting sub, and further including flowing jetting fluid out of the jetting sub continuously and simultaneously with supplying power fluid to the jet pump and receiving return fluid from the jet pump. 
     In an embodiment, the present invention provides a method of producing formation fluid from a hydrocarbon bearing formation wherein the jet pump further includes a jetting sub, and further including flowing jetting fluid out of the jetting sub intermittently and simultaneously with supplying power fluid to the jet pump and receiving return fluid from the jet pump. 
     In an embodiment, the present invention provides a method of producing formation fluid from a hydrocarbon bearing formation wherein the jet pump further includes a jetting sub, and further including:
         ceasing to receive return fluid from the jet pump;   flowing jetting fluid out of the jetting sub;   ceasing to flow jetting fluid out of the jetting sub; and   receiving return fluid from the jet pump via the return tubing string.       

     In an embodiment, the present invention provides a method of producing formation fluid from a hydrocarbon bearing formation wherein the jet pump further includes a jetting sub, wherein the spoolable multi-string tubing system further includes an auxiliary tubing string, and further including:
         establishing fluid communication between the jet pump and the auxiliary tubing string;   supplying jetting fluid to the jetting sub via the auxiliary tubing string; and   flowing jetting fluid out of the jetting sub.       

     In an embodiment, the present invention provides a method of producing formation fluid from a hydrocarbon bearing formation wherein the jet pump further includes a jetting sub, wherein the spoolable multi-string tubing system further includes an auxiliary tubing string, and further including:
         establishing fluid communication between the jet pump and the auxiliary tubing string;   ceasing to supply power fluid to the jet pump;   ceasing to receive return fluid from the jet pump;   supplying jetting fluid to the jetting sub via the auxiliary tubing string;   flowing jetting fluid out of the jetting sub;   ceasing to flow jetting fluid out of the jetting sub;   supplying power fluid to the jet pump; and   receiving return fluid from the jet pump.       

     In an embodiment, the present invention provides a method of producing formation fluid from a hydrocarbon bearing formation wherein the jet pump further includes a data-sensing sub, wherein the spoolable multi-string tubing system further includes a communications line, and further including:
         operatively connecting the data-sensing sub and the communications line;   sensing data with the data-sensing sub; and   receiving the data at the surface via the communications line.       

     In an embodiment, the present invention provides a method of producing formation fluid from a hydrocarbon bearing formation wherein the wherein the venturi nozzle, venturi gap, and diffuser are located on a carrier sub, and further including:
         ceasing to supply power fluid to the jet pump;   ceasing to receive return fluid from the jet pump; and   supplying power fluid to the jet pump via the return tubing string to unseat the carrier sub and convey it to the surface via the supply tubing string.       

     In an embodiment, the present invention provides a method of producing formation fluid from a hydrocarbon bearing formation wherein the wherein the venturi nozzle, venturi gap, and diffuser are located on a carrier sub, and further including:
         ceasing to supply power fluid to the jet pump;   ceasing to receive return fluid from the jet pump;   supplying power fluid to the jet pump via the return tubing string to unseat the carrier sub and convey it to the surface via the supply tubing string; and   supplying power fluid to the jet pump via the supply tubing string to convey the carrier sub to the jet pump and seat the carrier sub in the jet pump.       

     In an embodiment, the venturi nozzle and diffuser are substantially parallel with the return tube. 
     In a further aspect, the present invention provides a method of producing formation fluids from a hydrocarbon bearing formation including:
         providing a jet pump having a jet pump intake, a venturi nozzle, a venturi gap, and a diffuser;   providing a permanent spoolable multi-string tubing system having two or more conduits in fluid communication with the jet pump, the two or more conduits comprising a permanent supply tubing string and a permanent return tubing string;   providing a production spoolable multi-string tubing system having two or more conduits in fluid communication with the jet pump and with the permanent spoolable multi-string tubing system, the two or more conduits comprising a production supply tubing string and a production return tubing string;   deploying the jet pump into a wellbore;   supplying power fluid to the jet pump via the production supply tubing string and permanent supply tubing string; and   receiving return fluid from the jet pump via the production return tubing string and permanent return tubing string.       

     In an embodiment, the present invention provides a method of producing formation fluids from a hydrocarbon bearing formation further including:
         providing a cleanout spoolable multi-string tubing system having two or more conduits, the two or more conduits comprising a cleanout supply tubing string and a cleanout return tubing string;   ceasing to supply power fluid to the jet pump;   ceasing to receive return fluid from the jet pump;   disconnecting the production spoolable multi-string tubing system from the permanent spoolable multi-string tubing system;   establishing fluid communication between the two or more conduits of the cleanout spoolable multi-string tubing system and the two or more conduits of the permanent spoolable multi-string tubing system;   supplying power fluid to the jet pump via the cleanout supply tubing string and permanent supply tubing string; and   receiving return fluid from the jet pump via the cleanout return tubing string and permanent return tubing string.       

     In an embodiment, the present invention provides a method of producing formation fluids from a hydrocarbon bearing formation wherein the jet pump further includes a jetting sub, and further including flowing jetting fluid out of the jetting sub. 
     In an embodiment, the present invention provides a method of producing formation fluid from a hydrocarbon bearing formation wherein the jet pump further includes a jetting sub, and further including flowing jetting fluid out of the jetting sub continuously and simultaneously with supplying power fluid to the jet pump and receiving return fluid from the jet pump. 
     In an embodiment, the present invention provides a method of producing formation fluid from a hydrocarbon bearing formation wherein the jet pump further includes a jetting sub, and further including flowing jetting fluid out of the jetting sub intermittently and simultaneously with supplying power fluid to the jet pump and receiving return fluid from the jet pump. 
     In an embodiment, the present invention provides a method of producing formation fluids from a hydrocarbon bearing formation wherein the jet pump further includes a jetting sub, and further including:
         ceasing to receive return fluid from the jet pump;   flowing jetting fluid out of the jetting sub;   ceasing to flow jetting fluid out of the jetting sub; and   receiving return fluid from the jet pump via the permanent return tubing string and production return tubing string.       

     In an embodiment, the present invention provides a method of producing formation fluid from a hydrocarbon bearing formation wherein the jet pump further includes a jetting sub, wherein the permanent spoolable multi-string tubing system further includes a permanent auxiliary tubing string, wherein the production spoolable multi-string tubing system further includes a production auxiliary tubing string, and further including:
         establishing fluid communication between the jet pump and the permanent auxiliary tubing string;   establishing fluid communication between the permanent auxiliary tubing string and the production tubing string;   supplying jetting fluid to the jetting sub via the production auxiliary tubing string and the permanent auxiliary tubing string; and   flowing jetting fluid out of the jetting sub.       

     In an embodiment, the present invention provides a method of producing formation fluid from a hydrocarbon bearing formation wherein the permanent spoolable multi-string tubing system further includes a permanent auxiliary tubing string, wherein the production spoolable multi-string tubing system further includes a production auxiliary tubing string, and further including:
         establishing fluid communication between the jet pump and the permanent auxiliary tubing string;   establishing fluid communication between the permanent auxiliary tubing string and the production tubing string;   ceasing to supply power fluid to the jet pump;   ceasing to receive return fluid from the jet pump;   supplying jetting fluid to the jetting sub via the production auxiliary tubing string and the permanent auxiliary tubing string;   flowing jetting fluid out of the jetting sub;   ceasing to flow jetting fluid out of the jetting sub;   supplying power fluid to the jet pump; and   receiving return fluid from the jet pump.       

     In an embodiment, the present invention provides a method of producing formation fluid from a hydrocarbon bearing formation wherein the jet pump further includes a data-sensing sub, wherein the permanent spoolable multi-string tubing system further includes a permanent communications line, wherein the production spoolable multi-string tubing system further includes a production communications line, and further including:
         operatively connecting the data-sensing sub and the permanent communications line;   operatively connecting the permanent communications line and the production communications line;   sensing data with the data-sensing sub; and   receiving the data at the surface via the communications line.       

     In an embodiment, the present invention provides a method of producing formation fluid from a hydrocarbon bearing formation wherein the wherein the venturi nozzle, venturi gap, and diffuser are located on a carrier sub, and further including:
         ceasing to supply power fluid to the jet pump;   ceasing to receive return fluid from the jet pump; and   supplying power fluid to the jet pump via the production return tubing string and permanent return tubing string to unseat the carrier sub and convey it to the surface via the supply tubing string.       

     In an embodiment, the present invention provides a method of producing formation fluid from a hydrocarbon bearing formation wherein the wherein the venturi nozzle, venturi gap, and diffuser are located on a carrier sub, and further including:
         ceasing to supply power fluid to the jet pump;   ceasing to receive return fluid from the jet pump;   supplying power fluid to the jet pump via the production return tubing string and permanent return tubing string to unseat the carrier sub and convey it to the surface via the supply tubing string; and   supplying power fluid to the jet pump via the production supply tubing string and permanent supply tubing string to convey the carrier sub to the jet pump and seat the carrier sub in the jet pump.       

     In a further aspect, the present invention provides a method of producing formation fluid from a hydrocarbon bearing formation including:
         providing a spoolable multi-string tubing system having two or more conduits and an auxiliary tubing string, the two or more conduits comprising a supply tubing string and a return tubing string;   providing a jet pump having a jet pump intake, a venturi nozzle, a venturi gap, a diffuser, and a jetting sub;   establishing fluid communication between the two or more conduits and the jet pump, and between the auxiliary tubing string and the jet pump;   deploying the jet pump into a wellbore;   supplying power fluid to the jet pump via the supply tubing string;   receiving return fluid from the jet pump via the return tubing string;   supplying jetting fluid to the jetting sub via the auxiliary tubing string; and   flowing jetting fluid out of the jetting sub.       

     In a further aspect, the present invention provides a method of producing formation fluid from a hydrocarbon bearing formation comprising:
         providing a spoolable multi-string tubing system having two or more conduits and an auxiliary tubing string, the two or more conduits comprising a supply tubing string and a return tubing string;   providing a jet pump having a jet pump intake, a venturi nozzle, a venturi gap, a diffuser, and a jetting sub;   establishing fluid communication between the two or more conduits and the jet pump, and between the auxiliary tubing string and the jet pump;   deploying the jet pump into a wellbore;   supplying power fluid to the jet pump via the supply tubing string;   receiving return fluid from the jet pump via the return tubing string;   ceasing to supply power fluid to the jet pump;   ceasing to receive return fluid from the jet pump;   supplying jetting fluid to the jetting sub via the auxiliary tubing string;   flowing jetting fluid out of the jetting sub;   ceasing to flow jetting fluid out of the jetting sub;   supplying power fluid to the jet pump; and   receiving return fluid from the jet pump.       

     In a further aspect, the present invention provides a system for producing formation fluids from a hydrocarbon bearing formation comprising. The system includes: a jet pump having a jet pump intake, a venturi nozzle, a venturi gap, and a diffuser; a permanent spoolable multi-string tubing system having two or more conduits for establishing fluid communication with the jet pump, the two or more conduits including a permanent supply tubing string and a permanent return tubing string; and a production spoolable multi-string tubing system having two or more conduits for establishing fluid communication with the jet pump and with the permanent spoolable multi-string tubing system, the two or more conduits including a production supply tubing string and a production return tubing string. 
     In an embodiment, the system further includes a cleanout spoolable multi-string tubing system having two or more conduits, the two or more conduits including a cleanout supply tubing string and a cleanout return tubing string, for establishing fluid communication between the two or more conduits of the cleanout spoolable multi-string tubing system and the two or more conduits of the permanent spoolable multi-string tubing system. 
     In an embodiment, the jet pump further includes a jetting sub for flowing jetting fluid out of. 
     In an embodiment, the jet pump further includes a jetting sub for flowing jetting fluid out of; the permanent spoolable multi-string tubing system further includes a permanent auxiliary tubing string for establishing fluid communication with the jet pump for supplying jetting fluid to the jetting sub; and the production spoolable multi-string tubing system further includes a production auxiliary tubing string for establishing fluid communication with the jet pump and with the permanent auxiliary tubing string. 
     In an embodiment, the jet pump further includes a data-sensing sub; the permanent spoolable multi-string tubing system further includes a permanent communications line for operatively connecting to the data-sensing sub; and the production spoolable multi-string tubing system further includes a production communications line for operatively connecting to the permanent communications line. 
     In an embodiment, the venturi nozzle, venturi gap, and diffuser are located on a carrier sub for unseating and conveying to the surface via the production supply tubing string and permanent supply tubing string returning to the surface when power fluid is supplied to the jet pump via the production return tubing string and permanent return tubing string. 
     Other aspects and features of the present invention will become apparent to one ordinarily skilled in the art upon review of the following description of specific embodiments of the invention in conjunction with the accompanying figures. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Embodiments of the present invention will now be described, by way of example only, with reference to the attached Figures, wherein: 
         FIG. 1  is a schematic illustrating an embodiment of a fluid recovery system for producing formation fluid from a subsurface or subterranean hydrocarbon bearing formation of the present invention; 
         FIG. 2  is a jet pump of the present invention; 
         FIG. 3  is a jet pump of the present invention having a jetting sub; 
         FIG. 4  is a spoolable multi-string tubing system for use with a jet pump of  FIG. 2  or  3 ; 
         FIG. 5  is a cross section of one embodiment of a jet pump body of the jet pump of  FIG. 2 ; 
         FIG. 6  is a cross section of a further embodiment of a jet pump body of the jet pump of  FIG. 2  having a carrier sub; 
         FIG. 7  is a cross section of one embodiment of a jet pump body of the jet pump of  FIG. 3 ; 
         FIG. 8  is a jet pump of the present invention having an auxiliary tubing string; 
         FIG. 9  is a spoolable multi-string tubing system for use with the jet pump of  FIG. 8 ; 
         FIG. 10  is a cross section of a jet pump body of the jet pump of  FIG. 8 ; 
         FIG. 11  is a jet pump of the present invention having a data-sensing sub; 
         FIG. 12  is a spoolable multi-string tubing system for use with the jet pump of  FIG. 11 ; 
         FIG. 13  is a jetting sub of the present invention; 
         FIG. 14  is a jetting sub of the present invention having a back-pressure valve; 
         FIG. 15  is one embodiment of a jetting nozzle of the present invention; 
         FIG. 16  is a jet pump intake of the present invention; 
         FIG. 17  depicts a method of the present invention of using one embodiment of a jet pump and spoolable multi-string tubing system to produce formation fluid; 
         FIG. 18  depicts a method of the present invention of using one embodiment of a jet pump and spoolable multi-string tubing system to sequentially produce formation fluid and eliminate obstructions from a wellbore; 
         FIG. 19  depicts a method of the present invention of using one embodiment of a jet pump and spoolable multi-string tubing system to sequentially remove wellbore fluid and eliminate obstructions from a wellbore; 
         FIG. 20  depicts a method of the present invention of using the jet pump and spoolable multi-string tubing system of  FIG. 19  to sequentially remove wellbore fluid, and simultaneously remove wellbore fluid and eliminate obstructions from a wellbore; 
         FIG. 21  depicts a method of the present invention of using the jet pump and spoolable multi-string tubing system of  FIG. 19  to simultaneously remove wellbore fluid and eliminate obstructions from a wellbore; 
         FIG. 22  is a schematic illustrating one embodiment of a fluid recovery system for producing formation fluid from a subsurface or subterranean hydrocarbon bearing formation of the present invention; 
         FIG. 23  is a production spoolable multi-string tubing system of the present invention attached to a permanent spoolable multi-string tubing system of the present invention; and 
         FIG. 24  is a schematic illustrating deployment of a jet pump and spoolable multi-string tubing system of the present invention for a cleanout operation. 
     
    
    
     DETAILED DESCRIPTION 
     Generally, the present invention provides a method and system for multi-string tubing jet pump system for fluid production. 
     System 
       FIG. 1  depicts an embodiment of a fluid recovery system for producing formation fluid  10  from a subsurface or subterranean hydrocarbon bearing formation  20  via a wellbore  30 . A jet pump  150  is run on the end of a Spoolable, Multi-string Tubing System (SMTS)  100 . The SMTS  100  may include two or more conduits, for example a supply tubing string  110  and a return tubing string  120 . The SMTS  100  is hung off in the wellhead  140  which is configured to provide separate surface tie-ins for each of the tubing strings in the SMTS  100 . The SMTS  100  is run through a wellbore  30 . The wellbore  30  may be cased. 
     Power fluid  70  may flow from the injection line  650  to the supply tubing string  110  of the SMTS  100 . The power fluid  70  is typically either water- or hydrocarbon-based. The downhole end of the SMTS  100  is in fluid communication with the jet pump  150 , which is deployed into the wellbore  30  to produce formation fluid  10 . Inside the jet pump  150 , formation fluid  10  is combined with the power fluid  70 ; the resulting combination is return fluid  160 . Return fluid  160  may be used as power fluid  70 . 
     Return fluid  160  may flow from the return tubing string  120  to a production handling system  580  via a surface flowline  590 . This process operates on an on-going basis to continuously produce formation fluid  10  from the hydrocarbon bearing formation  20 . Gas flow (not shown) from the hydrocarbon bearing formation  20  may flow up through up through an annulus  595  in the wellbore  30  to a production handling system  580  via a surface flowline  590 . 
     At the production handling system, produced return fluid  160  may flow through the sales line  600  for further processing or other use. A fixed quantity of return fluid  160  may remain in the production handling system for use as power fluid  70  in the jet pump  150 . Return fluid  160  may flow through a pump skid suction line  610  and solids may be removed by an in-line filter system  620 . 
     A chemical injection pump  630  may be present and in fluid communication with the pump skid suction line  610  via a chemical injection line  640 . The chemical injection pump  630  may be used to administer chemicals to, for example, prevent scale and corrosion, and mitigate the detrimental effects to the SMTS  100  and jet pump  150  of exposure to, for example, paraffin. The return fluid  160  will flow to one or more pumps  660 , which may be driven by one or more motors  670 . Return fluid  160  that will now be used as (and referred to as) power fluid  70  flows into the injection line  650 . A flow meter  680  may be present to measure the flow rate of the power fluid  70 . A pressure indicator  690  (for example a pressure transducer or pressure gauge) may be present to measure pressure in the injection line  650 . A pressure relief valve  700  may be present to release excessive pressure into the pump skid suction line  610 , which has a lower pressure than the injection line  650 . 
     Jet Pump 
       FIG. 2  depicts an embodiment of a jet pump  150  for use with a SMTS  100  wherein the SMTS  100  includes a supply tubing string  110  and a return tubing string  120 . Connectors  190  connect a power fluid inlet  200  and the supply tubing string  110 , and a return fluid outlet  210  and the return tubing string  120 . The connectors  190  may be threaded, welded, or otherwise adapted to connect the jet pump body  220  with the supply tubing string  110  and the return tubing string  120 . The jet pump body  220  may, for example, have a unibody design (as illustrated), or be a dual barrel jet pump body (not shown). 
     Power fluid  70  flows through the power fluid inlet  200  into the jet pump body  220 , causing formation fluid  10  to flow into the jet pump body  220  through a jet pump intake  240 . Power fluid  70  and formation fluid  10  are combined as return fluid  160  in the jet pump body  220 . The return fluid  160  flows from the jet pump body  220  and into the return fluid outlet  210 . 
       FIG. 3  depicts an embodiment of a jet pump  150  having a jetting sub  250 . The jet pump body  220  may be adapted to direct power fluid  70  or return fluid  160  to a jetting sub  250 . Jetting fluid  260  flows out of a jetting nozzle  270 . Jetting fluid  260  is any fluid, for example power fluid  70 , return fluid  160 , or wellbore treatment fluid (not shown), that flows to the jetting sub  250 . 
     SMTS 
       FIG. 4  depicts an embodiment of the SMTS  100  for use with the jet pump  150  of  FIG. 2 . The supply tubing string  110  and the return tubing string  120  may be encapsulated in a single bundle  280  to facilitate deployment or retrieval with a single running operation using a conventional coiled tubing unit with modified injector chains. The bundle  280  may include an exterior polymer coating that is resistant to the effects of exposure to corrosive gases and fluids. The supply tubing string  110  and the return tubing string  120  are substantially parallel with one another. As illustrated by  FIG. 4 , the supply tubing string  110  and the return tubing string  120  may be laterally disposed with respect to one another. The tubing string  110  and the return tubing string  120  may abut along their long axes or, as illustrated in  FIG. 4 , may be positioned apart from one another. 
     When using the SMTS  100 , only a single coiled tubing unit ( FIG. 24 ) is necessary to install or retrieve the tubing string, reducing the time required for such operations compared to use of concentric tubing. Further, in some cases the size of the wellbore casing will be too restrictive to allow the use of concentric tubing but will be suitable for use of a SMTS  100 . 
     Jet Pump Body 
       FIG. 5  is a cross-section of one embodiment of the jet pump body  220  of  FIG. 2 . Power fluid  70  flows into a venturi nozzle  290 . While flowing through the venturi nozzle  290 , the power fluid  70  flows past a venturi gap  300  between the venturi nozzle  290  and a diffuser  310 , creating a low pressure condition at the venturi gap  300 . The low pressure condition causes formation fluid  10  to flow into a jet pump intake  240  and to the venturi gap  300 . Upon entering the venturi gap  300  and the diffuser  310 , formation fluid  10  combines with power fluid  70 , forming return fluid  160 . The return fluid  160  flows through a return tube  320  and into a return fluid outlet  210 . 
     A check valve  330  may prevent backflow when flowing power fluid  70  is not flowing through the venturi nozzle  290 , as may occur, for example, when the jet pump  150  ( FIG. 2 ) is in a jetting mode (see  FIG. 18 ). 
       FIG. 6  is a cross section of a further embodiment of the jet pump body  220  wherein the venturi nozzle  290 , the venturi gap  300 , and a diffuser  310  are all located on a carrier sub  750 . The carrier sub  750  is seated in the jet pump body  220  during normal production operations, but is not integral with the jet pump body  220 . The carrier sub  750  is adapted to travel up the supply tubing string  110  of the SMTS  100  via the power fluid inlet  200 . To cause the carrier sub  750  to travel up the supply tubing string  110 , the flow of power fluid  70  from the power fluid inlet  200  and the flow of return fluid  160  into the return fluid outlet  210  are reversed, and power fluid  70  is supplied to the jet pump  150  via the return tubing string  120  to unseat the carrier sub and convey it to the surface. The carrier sub  750  may then be returned to the jet pump body  220  by resuming normal flow of power fluid  70  from the power fluid inlet  200  and the flow of return fluid  160  into the return fluid outlet  210 , and by supplying power fluid  70  to the jet pump via the supply tubing string to seat the carrier sub  750  in the jet pump  150 . Alternatively, a second carrier sub (not shown) may take the place of the carrier sub  750 . The carrier sub  750 , and with it the venturi nozzle  290 , the venturi gap  300 , and a diffuser  310 , may be circulated to the surface without withdrawing the jet pump  150  from the wellbore  30 . The carrier sub  750  and its use thus allow retrieval of the venturi nozzle  290 , the venturi gap  300 , and a diffuser  310  to facilitate, for example, inspection, cleaning, or changing parts. 
       FIG. 7  is a cross section of a further embodiment of the jet pump body  220  wherein the jet pump body  220  includes a jetting sub  250 . At least a portion of the return fluid  160  may flow through the return tube  320  into the jetting sub  250 . 
     Jet Pump with Auxiliary Tubing String 
       FIGS. 8 and 9  depict an embodiment of a jet pump  150  for use with a SMTS  100  wherein the SMTS  100  includes an auxiliary tubing string  380 . A supply tubing string  110 , a return tubing string  120 , and the auxiliary tubing string  380  are encapsulated in a single bundle  280 . The supply tubing string  110 , the return tubing string  120 , and the auxiliary tubing string  380  are all substantially parallel with, and laterally disposed with respect to, one another. A jetting sub  250  may be in fluid communication with the auxiliary tubing string  380 . Jetting fluid  260  flows from the auxiliary tubing string  380  to the jetting sub  250 . 
       FIG. 10  is a cross-section of the jet pump body  220  of  FIG. 8  wherein an auxiliary tubing string  380  is in fluid communication with a jetting flow passage  340  through which jetting fluid  260  flows to the jetting sub  250 . 
     Jet Pump with Data-Sensing Sub 
       FIGS. 11 and 12  depict an embodiment of a jet pump  150  for use with a SMTS  100  wherein the SMTS  100  includes a communications line  390 . A supply tubing string  110 , a return tubing string  120 , and the communications line  390  are encapsulated in a single bundle  280 . The supply tubing string  110 , the return tubing string  120 , and the communications line  390  are all substantially parallel with, and laterally disposed with respect to, one another. The communications line  390  may be a small tubing string or an electrical conductor, include, for example, hydraulic, electric, or fiber optic communication means. A communications connector  400  operatively connects a data-sensing sub  410  with the communications line  390 . The communications connector  400  may be threaded, welded, or otherwise adapted to operatively connect the data-sensing sub  410  with the communications line  390 . When data such as bottomhole pressure, temperature, or both are required, data from the data-sensing sub  410  is received at the surface electronically or through pressure communication. Examples of data that the data-sensing sub  410  may be adapted to receive include temperature and pressure. 
     Jetting Sub 
       FIG. 13  depicts a jetting sub  250  for a jet pump  150 , with a jetting nozzle  270 . Jetting fluid  260  flows from a jet pump body  220 , through the jetting sub  250 , and out the jetting nozzle  270 . 
       FIG. 14  depicts a jetting sub  250  for a jet pump  150  wherein access by jetting fluid  260  to the jetting nozzle  270  is subject to a back-pressure valve  460 . The back-pressure valve  460  may include, for example, a ball  470 , a spring  480 , and a seat  490 . The back-pressure valve  460  may be adapted to open at a selected back-pressure setting. The back-pressure setting is selected by selecting a spring rate, distance, or combination thereof, of the spring  480 . When fluid pressure equal to or greater than the back-pressure setting is applied, the spring  480  is compressed and jetting fluid  260  flows through the jetting nozzle  270 . 
     Jetting Nozzle 
       FIG. 15  depicts a jetting nozzle  270  for a jetting sub  250  wherein jetting fluid  260  flows through a converging jetting passage  500  and a diverging jetting passage  510 . The diverging jetting passage  510  may be present on a threaded insert  520 . The converging jetting passage  500  and the diverging jetting passage  510  form a jetting pinch  530 . The jetting pinch  530  is sized to provide back-pressure for the jetting nozzle  270 . Entrained particulates that flow in the jetting fluid  260  will eddy in the diverging jetting passage  510  preferentially to in the converging jetting passage  500 , protecting the converging jetting passage  500  from damage. 
     Jet Pump Intake 
       FIG. 16  depicts a jet pump intake  240  for a jet pump  150 , which includes slots  550 . A dimension  560  of the slots  550  is selected based on the size of a venturi gap  300  in the jet pump body  220  ( FIG. 5 ) and the size of any material in the wellbore  30  which may enter the jet pump intake  240 . The dimension  560  is selected to be large enough to admit most particulates that will be found in a given wellbore  30  but small enough to prevent intake of particulates that are large enough to plug the venturi gap  300 . 
     Method of Using a Jet Pump 
       FIG. 17  illustrates one embodiment of a method of using a jet pump  150  to produce formation fluid  10 . The jet pump  150  includes a jet pump body  220 , a jetting sub  250  and a jet pump intake  240 . Formation fluid  10  may be pumped to the surface by the jet pump  150 . 
     Method of Using a Jet Pump Including a Jetting Sub 
       FIG. 18  illustrates one embodiment of a method of using a jet pump  150  to produce formation fluid  10 . The jet pump  150  includes a jet pump body  220 , a jetting sub  250  and a jet pump intake  240 . The jetting sub  250  includes a jetting nozzle  270 . Formation fluid  10  may be pumped to the surface by the jet pump  150  (production mode). If a wellbore obstruction  570  (for example a sand bridge) is present, suction at the jet pump intake  240  may cease and jetting fluid  260  may be emitted from the jetting nozzle  270  to disperse the wellbore obstruction  570  (jetting mode). Once the wellbore obstruction  570  is sufficiently dispersed, emission of jetting fluid  260  from the jetting nozzle  270  may cease and production of formation fluid  10  by the jet pump  150  may be resumed. Dispersal of a wellbore obstruction  570  is provided as an example and is not the sole application of emission of jetting fluid  260  from the jetting sub  250 . 
     Changing from the production mode to the jetting mode may be accomplished by reconfiguring a return tubing string  120  such that power fluid  70  is supplied to the jet pump body  220  through both a supply tubing string  110  and the return tubing string  120 . The same change may be accomplished by blocking the return tubing string  120 . Changing from the jetting mode to the production mode may be accomplished by reconfiguring the return tubing string  120  to remove return fluid  160 . A jet pump  150  having a jet pump body  220  as in  FIG. 7  is suitable for use in the method of  FIG. 18 . Other embodiments of a jet pump body  220 , which may, for example, include a jetting sub  250  having a back-pressure valve  460  ( FIG. 14 ) may allow simultaneous emission of jetting fluid  260  from the jetting nozzle  270  while producing formation fluid  10 . Simultaneous emission of jetting fluid  260  from the jetting nozzle  270  while producing formation fluid  10  may be intermittent with merely producing formation fluid or may be constant. 
     Method of Using a Jet Pump Including an Auxiliary Tubing String 
       FIG. 19  illustrates a further embodiment of a method of using a jet pump  150 . The jet pump  150  further includes an auxiliary tubing string  380  in fluid communication with the jetting sub  250 , and may have a jet pump body  220  configured, for example, as in  FIG. 10 . Similarly to the method of  FIG. 18 , the jet pump  150  may be used in a production mode or a jetting mode. Changing from the production mode to the jetting mode may be accomplished by flowing jetting fluid  260  through the auxiliary tubing string  380 , and reducing or removing fluid pressure from a supply tubing string  110 . Changing from the jetting mode to the production mode may be accomplished by ceasing to flow jetting fluid  260  through the auxiliary tubing string  380  and supplying power fluid  70  to the supply tubing string  110  at a sufficient fluid pressure to generate suction at the jet pump intake  240 . 
       FIG. 20  illustrates a further embodiment of a method of using the jet pump  150  of  FIG. 19 . The jet pump  150  may be used in the production mode or in production and jetting mode. Changing from the production mode to jetting and production mode may be accomplished by flowing jetting fluid  260  through the auxiliary tubing string  380 . Changing from the jetting mode to the production mode may be accomplished by ceasing to flow jetting fluid  260  through the auxiliary tubing string  380 . 
       FIG. 21  illustrates a further embodiment of a method of using the jet pump  150  of  FIG. 19 . Formation fluid  10  may be pumped to the surface by the jet pump  150  while jetting fluid  260  continuously flows from the jetting nozzle  270 . 
     Permanent and Production SMTS 
       FIG. 22  depicts an embodiment of a fluid recovery system for producing formation fluid  10  from a subsurface or subterranean hydrocarbon bearing formation  20  via a wellbore  30 . A jet pump  150  is run on the end of a permanent SMTS  730 . The permanent SMTS  730  may include two or more conduits, for example a permanent supply tubing string  760  and a permanent return tubing string  770 . A production SMTS  740  is hung off in a wellhead  140 . The production SMTS  740  may include two or more conduits, for example a production supply tubing string  780  and a production return tubing string  790 . The permanent SMTS  730  is in fluid communication with the production SMTS  740 . The permanent SMTS  730  may be connected to the jet pump  150  and the production SMTS  740  may be connected to the injection line  650  and the surface flowline  590 . 
       FIG. 23  depicts a production SMTS  740  in fluid communication with a permanent SMTS  730 . The production SMTS  740  is connected to the permanent SMTS  730  by connectors  190 . Connectors  190  connect the permanent SMTS  730  with the production SMTS  740 . When cleanout is desired, the production SMTS  740  may be disconnected from the permanent SMTS  730  and a cleanout SMTS  720  ( FIG. 24 ) may be connected to the permanent SMTS  730 . It is thus not necessary to remove the permanent SMTS  730  and the jet pump  150  to reconfigure the jet pump  150  from production to cleanout. While the permanent SMTS  730  and production SMTS  740  each have two conduits, analogous embodiments wherein, for example the permanent SMTS  730  includes a permanent auxiliary tubing string (not shown) or a permanent communications line (not shown), and the production SMTS  740  includes a production auxiliary tubing string (not shown) or a production communications line (not shown). All embodiments discussed above for methods of production may substitute a permanent SMTS  730  in fluid communication with a production SMTS  740  for a SMTS  100 . 
     Cleanout System 
       FIG. 24  depicts a system including one embodiment of a multi-string tubing system and jet pump for removing wellbore fluid  710  from a subsurface or subterranean hydrocarbon bearing formation  20  via a wellbore  30 . The wellbore fluid  710  may include entrained solids. A pressure pump truck  40  includes a surface pump  50  and a fluid storage tank  60 . Power fluid  70  is conveyed to a coiled tubing unit  80 . The power fluid  70  is typically either water- or hydrocarbon-based. The coiled tubing unit  80  includes a coiled tubing reel  90  with a cleanout SMTS  720 . The cleanout SMTS  720  may include two or more conduits, for example a cleanout supply tubing string  800  and a cleanout return tubing string  810 . 
     Power fluid  70  flows in a cleanout supply tubing string  800  of the cleanout SMTS  720 . The cleanout SMTS  720  is deployed using a coiled tubing injector  130  with injector blocks adapted to run the cleanout SMTS  720 . The cleanout SMTS  720  is positioned through a wellhead  140  and into the wellbore  30 . The downhole end of the permanent SMTS  730  includes a jet pump  150  powered by power fluid  70 , which is deployed into the wellbore  30  to remove wellbore fluid  710 . Inside the jet pump  150 , wellbore fluid  710  is combined with the power fluid  70 ; this combination is return fluid  160 . 
     Return fluid  160  is pumped to the surface via the permanent return tubing string  770  and the cleanout return tubing string  810 . The return fluid  160  exits the coiled tubing reel  90  and is conveyed to a return tank  170 . Any gas from the wellbore  30  flows into a gas line  180 . The gas line  180  may be shut in or opened to gas flow during use of the jet pump  150 . 
     In the preceding description, for purposes of explanation, numerous details are set forth in order to provide a thorough understanding of the embodiments of the invention. However, it will be apparent to one skilled in the art that these specific details are not required in order to practice the invention. 
     The above-described embodiments of the invention are intended to be examples only. Alterations, modifications and variations can be effected to the particular embodiments by those of skill in the art without departing from the scope of the invention, which is defined solely by the claims appended hereto.

Technology Classification (CPC): 4