Method and apparatus for distributing fluids within a subterranean wellbore

Abstract

A method and apparatus for distributing fluids within a subterranean borehole wherein a submersible pump is introduced into the borehole at a first location. An intake port of the pump is connected to the first end of an intake duct having an unconnected second end located at a second location within the wellbore from which location fluid is to be withdrawn. An output port of the pump is connected to a first end of a second duct having an unconnected second end at a third location within the wellbore into which location fluid is to be introduced. By activating the pump, fluids, such as scale and corrosion inhibitors, are distributed from above the intake of a production pump to as low in the borehole as is required to protect wellbore contents.

What is claimed is: 
     
       1. Apparatus for distributing fluids around equipment including a production pump to be protected within a subterranean borehole comprising: a submersible pump being positioned at a first location within the borehole and having an intake port and an output port;   means, connected to said submersible pump, for activating said submersible pump;   an intake duct having a first end connected to said intake port and having a free second end at a second location within the borehole for withdrawing fluid from the second location said second location being on a first side of the equipment to be protected; and   an output duct having a first end connected to said output port and having a free second end at a third location within the wellbore for introducing fluids into the third location, said third location being on a second side of the equipment to be protected, said equipment to be protected including a production pump having an intake and wherein said second location is above said intake and wherein said third location is below said intake.   
     
     
       2. The apparatus as recited in claim 1 further comprising a casing having perforations in a production zone and wherein said third location is below said perforations. 
     
     
       3. The apparatus as recited in claim 1 wherein said output duct comprises a tailpipe. 
     
     
       4. The apparatus as recited in claim 1 wherein said pump is a single stage pump. 
     
     
       5. A method for distributing fluids within a subterranean borehole around equipment to be protected comprising the steps of: introducing into the borehole at a first location apparatus comprising a submersible pump having an intake port connected to a first end of an intake duct and having an output port connected to a first end of an output duct;   positioning a free second end of said intake duct within the borehole at a second location from which fluid is to be withdrawn, the second location being on a first side of the equipment to be protected;   locating a free second end of said output duct within the borehole at a third location into which fluid is to be introduced, the third location being on a second side of the equipment to be protected;   activating said submersible pump; and   providing a treatment fluid to said second location, said treatment fluid selected from the group consisting of a corrosion inhibitor, scale inhibitor, a defoamer, an emulsion breaker, a focculant, a paraffin inhibitor, a bactericide and mixtures thereof. .Iadd.   
     
     
       6.  In a well installation, having casing, a string of tubing extending to a downhole centrifugal pumping assembly, defining an annulus between the casing and the tubing and pumping assembly, and means at the surface for introducing inhibiting chemicals into the annulus, the pumping assembly including a centrifugal primary pump driven by an electrical motor located below the pump and separated by a seal section for preventing well fluids from entering the motor, the improvement comprising in combination: a centrifugal secondary pump having an upper end adapted to be connected to the bottom of the primary pump and a lower end adapted to be connected to the top of the seal section;   the secondary pump having an intake port on its upper end adapted to be connected to an intake tube that extends above an intake of the primary pump, terminating in the annulus; and   the secondary pump having a discharge port on its lower end adapted to be connected to a discharge tube that extends downwardly through the annulus alongside the motor to a point in the annulus below the motor, for pumping inhibiting chemicals drawn from the annulus to a location below the motor, which then flow upwardly around the motor and into the intake of the primary pump. .Iaddend. .Iadd.   
     
     
       7.  Apparatus for introducing inhibiting chemicals into a wellbore comprising: (a) a production pump at a first location in the wellbore;   (b) a secondary pump at a second location within the wellbore further comprising: (i) an intake tube; and   (ii) a discharge tube;     (c) a motor for driving said production pump above discharge tube. .Iaddend. .Iadd.   
     
     
       8.  In a well installation, having casing, a string of tubing extending to a downhole pumping assembly, defining an annulus between the casing and the tubing and pumping assembly, and means at the surface for introducing inhibiting chemicals into the annulus, the pumping assembly including a primary pump driven by an electrical motor located below the pump and separated by a seal section for preventing well fluids from entering the motor, the improvement comprising in combination: a secondary pump having an upper end adapted to be connected to the bottom of the primary pump and a lower end adapted to be connected to the top of the seal section;   the secondary pump having an intake pump on its upper end adapted to be connected to an intake tube that extends above an intake of the primary pump, terminating in the annulus; and   the secondary pump having a discharge port on its lower end adapted to be connected to a discharge tube that extends downwardly through the annulus alongside the motor to a point in the annulus below the motor, for pumping inhibiting chemicals drawn from the annulus to a location below the motor, which then flow upwardly around the motor and into the intake of the primary pump. .Iaddend. .Iadd.   
     
     
       9.  Apparatus for introducing inhibiting chemicals into a wellbore comprising: (a) casing;   (b) tubing within the casing defining an annulus between the tubing and the casing;   (c) a pumping assembly substantially at the end of said tubing and further comprising: (i) a primary pump;   (ii) an electrical motor for driving said primary pump; and     (iii) a seal section between said pump and said motor;   (d) a secondary pump having an upper end connected to the bottom of said primary pump and a lower end connected to the top of said seal section and further comprising:   (i) an inhibitor intake port connected to an intake tube operably terminating in said annulus; and   (ii) a discharge port adapted to be connected to a discharge tube extending downwardly through said annulus alongside said motor to a point in said annulus below said motor. .Iaddend.