Gas lift assembly

Abstract

An apparatus ( 11 a ) for introduction of gas into a wellbore containing production tubing ( 12 a ) is provided. The apparatus consists of a conduit ( 30 a ) for location at least partly within the production tubing ( 12 a ), an inlet ( 32 a ) providing communication between the conduit ( 30 a ) and a wellbore annulus, and an outlet ( 34 a ) providing communication between the conduit and a reservoir ( 16 ). The apparatus therefore allows gas to be introduced into reservoir fluids at a distance from introduction of gas into the production tubing, so increasing the effective depth of gas introduction. A method of gas introduction is also described.

1 . An apparatus for use in a well having a wellbore containing production tubing, the apparatus comprising conduit means for location at least partly within the production tubing, inlet means for allowing communication between the conduit means and a wellbore annulus, and outlet means for allowing communication between the conduit means and a reservoir of the well.  
     
     
         2 . The apparatus of  claim 1 , wherein a first portion of said conduit means is provided within the production tubing while a second portion of said conduit means is provided upstream of the production comprises a major portion of said conduit means.  
     
     
         3 . The apparatus of  claim 2 , wherein said first portion comprises a minor portion of said conduit means, while said second portion comprises a major portion of said conduit means.  
     
     
         4 . The apparatus of any preceding claim, wherein said outlet means is provided upstream of said inlet means.  
     
     
         5 . The apparatus of any preceding claim, wherein said conduit means comprises tubing.  
     
     
         6 . The apparatus of  claim 5 , wherein said tubing is jointed tubing.  
     
     
         7 . The apparatus of  claim 5 , wherein said tubing is continuous tubing.  
     
     
         8 . The apparatus of  claim 5 , wherein said tubing is coiled tubing.  
     
     
         9 . The apparatus of any preceding claim, wherein said outlet means includes a valve.  
     
     
         10 . The apparatus of  claim 9 , wherein said inlet means includes a further valve.  
     
     
         11 . The apparatus of  claim 9  or  claim 10 , wherein said valve(s) is/are one-way valve(s).  
     
     
         12 . The apparatus of any preceding claim, wherein said inlet means is adapted to cooperate with a pre-existing aperture in the production tubing.  
     
     
         13 . The apparatus of any preceding claim, wherein the apparatus comprises seal means for forming a seal at or around said inlet means, in order to seek to prevent direct communication between the annulus and the production tubing.  
     
     
         14 . The apparatus of  claim 13 , wherein said seal means takes the forms of at least one elastomeric seal.  
     
     
         15 . The apparatus of any preceding claim, wherein the apparatus further comprises securing means for locating the apparatus at a desired point within the production tubing.  
     
     
         16 . The apparatus of  claim 15 , wherein said securing means is selectively engageable, allowing the apparatus to be retrieved if necessary.  
     
     
         17 . The apparatus of  claim 16 , wherein said securing means comprises retractable lock dogs.  
     
     
         18 . A well having a wellbore containing production tubing and further including an apparatus comprising conduit means for location at least partly within the production tubing, inlet means for allowing communication between the conduit means and a wellbore annulus, and outlet means for allowing communication between the conduit means and a reservoir of the well.  
     
     
         19 . The well of  claim 18 , wherein the well also provides a casing.  
     
     
         20 . The well of  claim 18  or  claim 19 , wherein a seal, such as a packer, is provided between the casing and the production tubing.  
     
     
         21 . A method of providing artificial lift to a well having a wellbore containing production tubing, the method comprising the steps of: 
 providing a conduit means comprising an inlet means and an outlet means;    locating the conduit means within the production tubing, and that the inlet means is in communication with a wellbore annulus and the outlet means is in communication with a reservoir of the well; and    introducing gas into the wellbore annulus, such that gas is transferred via the conduit means to reservoir fluids.    
     
     
         22 . The method of  claim 21 , wherein the outlet means is located further upstream than the inlet means.  
     
     
         23 . The method of  claim 21  or  claim 22 , wherein the wellbore further contains a seal within the annulus, located between the inlet means and the outlet means.  
     
     
         24 . The method of  claim 23 , wherein the seal comprises a packer.