Well treatment apparatus and method

Abstract

Apparatus and methods are disclosed for sequentially treating multiple zones in underground formation in a single trip of the well treatment work string. In the one embodiment, the work string includes composite tubing having electrical conductors embedded within the walls, the conductors enabling power transmission and two way communication between the surface and the sensor or detectors downhole so that real time data can be sensed and communicated. Isolation packers are actuated via electrical signals from the surface communicated to the bottom hole assembly via the conductors. A detector located in the bottom hole assembly may be provided to detect perforations or other anomalies in the casing, such as joints, enabling the surface controller to position packers properly in blank segments of casing so that well intervals can be properly isolated and the adjacent formation effectively treated.

What is claimed is:  
     
         1 . Apparatus for treating zones in a subterranean formation intersected by a wellbore that extends from the surface through the zones, the apparatus comprising: 
 a bottom hole assembly comprising a tubular sub, said tubular sub having an internal fluid passageway and a fluid port for conducting fluids from said internal passageway into the wellbore;    a composite tubing string having an internal flow bore and interconnected with said bottom hole assembly such that said flow bore of said tubing string and said fluid passageway of said tubular sub are in fluid communication.    
     
     
         2 . The apparatus of  claim 1  further comprising: 
 a controller located at the surface;  
 a sensor in said bottom hole assembly;  
 a conductor coupling said sensor to said surface controller, said conductor being embedded in said composite tubing string and extending from said bottom hole assembly to the surface.  
 
     
     
         3 . The apparatus of  claim 1  further comprising: 
 a controller located at the surface;  
 a packer on said bottom hole assembly;  
 a packer actuator for causing said packer to expand in response to an electrical signal transmitted by said-surface controller;  
 a conductor embedded in said composite tubing string coupling said packer actuator to said surface controller.  
 
     
     
         4 . The apparatus of  claim 3  further comprising: 
 an electric power supply at the surface;  
 a power distribution sub in said bottom hole assembly;  
 a conductor embedded in said composite tubing string coupling said surface power supply to said power distribution sub;  
 conductors in said bottom hole assembly coupling said power distribution sub to said packer actuator.  
 
     
     
         5 . The apparatus of  claim 2  wherein said sensor senses anomalies in the casing and transmits signals indicative of the anomaly to said surface controller via said conductor.  
     
     
         6 . The apparatus of  claim 5  wherein said sensor is a magnetoresistive sensor.  
     
     
         7 . The apparatus of  claim 5  further comprising: 
 a packer on said bottom hole assembly;  
 a packer actuator for causing said packer to expand in response to an electrical signal transmitted by said surface controller; and  
 a conductor embedded in said composite tubing string coupling said packer actuator to said surface controller.  
 
     
     
         8 . The apparatus of  claim 7  further comprising a conductor embedded in said composite tubing transmitting power from the surface to said bottom hole assembly, and transmitting data from said bottom hole assembly to said surface controller.  
     
     
         9 . The apparatus of  claim 8  further comprising a pressure sensor in said bottom hole assembly sensing pressure adjacent said fluid port and communicating the sensed pressure to said surface controller via a conductor in said composite tubing string.  
     
     
         10 . The apparatus of  claim 9  wherein said bottom hole assembly includes a plurality of packers supported along said tubular sub, said packers being sequentially actuatable in response to electrical signals from said surface controller.  
     
     
         11 . An apparatus for treating a subterranean zone in a formation that is intersected by a wellbore, the apparatus comprising: 
 a surface controller;    a composite tubing string extending from the surface into the wellbore;    a bottom hole assembly releaseably attached to said composite tubing string, said bottom hole assembly comprising a plurality of packers that are sequentially actuatable in response to electrical signals from said controller, and an actuator associated with each of said packers for selectively actuating its associated packer;    wherein said composite tubing string includes embedded conductors, and wherein said conductors couple said actuators with said surface controller.    
     
     
         12 . The apparatus of  claim 11  further comprising a hydraulic unit in said bottom hole assembly for generating hydraulic power; and wherein at least one of said actuators is a solenoid valve directing hydraulic fluid from said hydraulic unit to said associated packer in response to receiving a signal transmitted from said surface controller to said bottom hole assembly via a conductor embedded in said composite tubing.  
     
     
         13 . The apparatus of  claim 11  wherein at least one of said actuators is a propellant disposed in said bottom hole assembly adjacent to said associated packer and electrically ignited in response to a signal transmitted from said surface controller to said bottom hole assembly via a conductor embedded in said composite tubing.  
     
     
         14 . The apparatus of claim of  11  wherein at least one of said actuators is an electric motor disposed in said bottom hole assembly, said motor actuating to actuate its associated packer in response to receipt of a signal transmitted from said surface controller to said bottom hole assembly via a conductor embedded in said composite tubing.  
     
     
         15 . The apparatus of claim of  11  further comprising a detector assembly in said bottom hole assembly capable of detecting anomalies in the casing of the wellbore, said detector transmitting to the surface controller data relating to the anomalies via said embedded conductors.  
     
     
         16 . The apparatus of claim of  15  further comprising a sensor in said bottom hole assembly for sensing data indicative of a condition in the well bore and communicating the sensed data to the surface controller via said embedded conductors.  
     
     
         17 . The apparatus of  claim 16  further comprising a power supply on the surface, and wherein said embedded conductors transmit power from said power supply to said bottom hole assembly, transmit control signals from said surface controller to said bottom hole assembly, and transmit well bore data from said bottom hole assembly to said surface controller.  
     
     
         18 . The apparatus of  claim 11  further comprising a disconnect assembly connecting said bottom hole assembly to said composite tubing string, said disconnect being actuated electrically via electrical signals communicated from said surface controller via said embedded conductors.  
     
     
         19 . The apparatus of  claim 18  further comprising a latch releasably latching said plurality of packers on said bottom hole assembly.  
     
     
         20 . Apparatus for conducting well treatment operations in a wellbore that extends from the surface through a subterranean formation having producing zones, the apparatus comprising: 
 a work string extending into the wellbore from the surface;    a bottom hole assembly connected to said work string and having an elongate tubular member with a central flow bore and discharge ports;    a surface controller;    electrical conductors supported by said work string for communicating signals from said surface controller to said bottom hole assembly;    a plurality of packers supported on said tubular member, said packers being sequentially operable so as to isolate different intervals of the well bore in response to signals transmitted from said surface controller to said bottom hole assembly.    
     
     
         21 . The apparatus of  claim 20  further comprising a detector in said bottom hole assembly coupled to said surface controller via said conductors, said detector detecting segments of the well casing that are free of perforations and casing joints.  
     
     
         22 . The apparatus of  claim 20  further comprising a sensor in said bottom hole assembly coupled to said surface controller via said conductors.  
     
     
         23 . The apparatus of  claim 22  wherein said work string includes metal tubing and wherein said conductors extend between said bottom hole assembly and the surface in an umbilical supported by said metal tubing.  
     
     
         24 . The apparatus of  claim 22  wherein said work string includes composite tubing and wherein said conductors extend between said bottom hole assembly and the surface and are embedded in the wall of said composite tubing.  
     
     
         25 . The apparatus of  claim 20  further comprising: 
 a plurality of actuators, each of which being associated with a packer for selectively actuating its associated packer;  
 a hydraulic unit in said bottom hole assembly for generating hydraulic power;  
 wherein at least one of said actuators is a solenoid valve directing hydraulic fluid from said hydraulic unit to said associated packer in response to receiving a signal transmitted from the surface controller to said bottom hole assembly via said electrical conductors.  
 
     
     
         26 . The apparatus of  claim 20  further comprising: 
 a plurality of actuators, each of which being associated with a packer for selectively actuating its associated packer;  
 wherein at least one of said actuators is a propellant disposed in said tubular member adjacent to its associated packer and electrically ignited in response to a signal transmitted from said surface controller to said bottom hole assembly via said electrical conductors.  
 
     
     
         27 . The apparatus of  claim 22  wherein said sensor includes a pressure sensor sensing pressure indicative of the pressure in the well bore adjacent said tubular member.  
     
     
         28 . The apparatus of  claim 22  wherein said sensor is a differential pressure sensor sensing the pressure in the wellbore above and below one of said packers.  
     
     
         29 . The apparatus of  claim 22  wherein said sensor is a temperature sensor sensing temperature in the well bore adjacent said tubular member.  
     
     
         30 . A method of treating zones in a subterranean formation intersected by a cased well bore that extends from the surface through the zones, the method comprising: 
 placing into the wellbore a tubing string with a bottom hole assembly having a ported sub and a plurality of sequentially settable packers;    locating a blank segment of casing above the depth of a first producing zone;    setting a first packer in the blank region of casing to isolate a first well interval below the first packer from the annulus extending above the first packer;    pumping treatment fluid through the ported sub into the first isolated interval;    sensing within the first isolated interval at least one downhole parameter and communicating the sensed parameter to the surface via conductors that extend along the tubing string between the bottom hole assembly and the surface.    
     
     
         31 . The method of  claim 30  further comprising: 
 ceasing the pumping of treatment fluid when the sensed parameter meets a predetermined criteria.  
 
     
     
         32 . The method of  claim 30  further comprising: 
 ceasing the pumping of treatment fluid;  
 raising the bottom hole assembly to a position above the set first packer;  
 locating a blank segment of casing above the depth of a next producing zone;  
 setting a second packer in the blank region of casing to isolate a second well interval above the first packer and below the second packer from the annulus extending above the second packer;  
 pumping treatment fluid through the ported sub into the second isolated interval;  
 sensing within the second isolated interval at least one downhole parameter and communicating the sensed parameter to the surface via conductors that extend along the tubing string between the bottom hole assembly and the surface.  
 
     
     
         33 . A method of stimulating subterranean zones that are intersected by a wellbore comprising: 
 positioning a tubing string in the wellbore;    isolating a first interval of the wellbore adjacent to a first zone;    stimulating the first zone by pumping fluids through the tubing string into the first isolated interval;    sensing at least one downhole parameter while stimulating the first zone;    communicating the sensed parameters to the surface via conductors in the tubing string while stimulating the first zone.    
     
     
         34 . The method of  claim 33  further comprising sensing the pressure in the first isolated interval and ceasing the stimulation when the rate of change in the pressure sensed exceeds a predetermined value.  
     
     
         35 . The method of  claim 33  further comprising: 
 ceasing the stimulation of the first zone;  
 raising the tubing string in the well bore;  
 isolating an interval adjacent to a second zone;  
 stimulating the second zone by pumping fluids through the tubing string into the second isolated interval;  
 sensing parameters within the second isolated interval while stimulating the second zone;  
 communicating the sensed parameter to the surface via conductors in the tubing string while stimulating the second zone.  
 
     
     
         36 . A method of treating a subterranean formation having a casing extending through the formation, the casing having perforations adjacent the formation and casing joints adjacent the perforations, the method comprising: 
 lowering a detector assembly, packer and mandrel on a coiled tubing into the casing;    locating the perforations using the detector assembly;    transmitting the location of the perforations to the surface;    setting the packer to isolate the perforations; and    pumping fluid through ports in the mandrel and through the perforations and into the formation.    
     
     
         37 . The method of  claim 36  further comprising providing a conductor on the coiled tubing to transmit the location of the perforations to the surface.  
     
     
         38 . The method of  claim 36  further comprising sensing the pressure downhole providing and a conductor on the coiled tubing to transmit the pressure to the surface.  
     
     
         39 . The method of  claim 36  further comprising transmitting a signal from the surface through a conductor on the coiled tubing to actuate the packer.  
     
     
         40 . An apparatus for treating a formation adjacent a casing extending from the surface into a well, the casing having anomalies such as casing joints and perforations, comprising: 
 a coiled tubing having a flowbore and at least one conductor supported by a wall of said coiled tubing;    a detector assembly having a detector sensor to detect one or more of the anomalies in the casing, the detector assembly transmitting signals of the detection through said conductor to the surface;    a mandrel having a packer mounted thereon and a port in fluid communication with a flow passage through said mandrel and with said flowbore of said coiled tubing;    said detector assembly and mandrel being supported by said coiled tubing.    
     
     
         41 . The apparatus of  claim 40  wherein said detector sensor is a magnetoresistive sensor.  
     
     
         42 . The apparatus of  claim 40  wherein said detector sensor senses anomalies in the casing wall which form fringe effects that cause perturbations in the naturally induced magnetic field of the casing.  
     
     
         43 . The apparatus of  claim 40  wherein said detector sensor detects the perforations and determines the depth of the perforations.  
     
     
         44 . The apparatus of  claim 40  wherein said detector sensor detects the casing joints and determines the depth of the casing joints adjacent the formation.  
     
     
         45 . The apparatus of  claim 40  wherein said coiled tubing is metal tubing and said conductor is mounted on the interior or exterior wall of said metal tubing.  
     
     
         46 . The apparatus of  claim 40  wherein said coiled tubing is composite coiled tubing with said conductor embedded in a wall of the composite coiled tubing.  
     
     
         47 . The apparatus of  claim 40  wherein power is transmitted downhole through said conductor.  
     
     
         48 . The apparatus of  claim 47  wherein data is transmitted to the surface through said power conductor.  
     
     
         49 . The apparatus of  claim 40  further including a pressure sensor supported on said coiled tubing.  
     
     
         50 . The apparatus of  claim 49  wherein said pressure sensor senses the pressure adjacent a lower end of said mandrel.  
     
     
         51 . The apparatus of  claim 49  wherein said pressure sensor senses the pressure above said packer.  
     
     
         52 . The apparatus of  claim 49  wherein said pressure sensor senses the differential pressure between the pressure adjacent a lower end of said mandrel and the pressure above said packer.  
     
     
         53 . The apparatus of  claim 40  further including a temperature sensor supported on said coiled tubing.  
     
     
         54 . The apparatus of  claim 40  further including a load sensor supported on said coiled tubing.  
     
     
         55 . The apparatus of  claim 54  wherein said load sensor senses compression and/or tension on said coiled tubing.  
     
     
         56 . The apparatus of  claim 40  further comprising an electrically actuated valve, wherein said conductor conducts electricity causing actuation of said valve.  
     
     
         57 . The apparatus of  claim 40  wherein said conductor conducts electricity and further including a disconnect between said coiled tubing and said mandrel actuated electrically by said conductor.  
     
     
         58 . The apparatus of  claim 40  wherein said conductor conducts electricity and further including an anchor on said coiled tubing actuated electrically by said conductor.  
     
     
         59 . The apparatus of  claim 40  wherein said conductor conducts electricity and said packer is electrically actuable by said conductor.  
     
     
         60 . The apparatus of  claim 40  wherein said conductor conducts electricity and said packer is actuable by a propellant which is actuated electrically by said conductor.  
     
     
         61 . The apparatus of  claim 40  further including a latch releasably latching said packer onto said mandrel.  
     
     
         62 . The apparatus of  claim 61  further including a closure member for closing said packer upon releasing said packer from said mandrel.  
     
     
         63 . The apparatus of  claim 40  further including another packer mounted on said mandrel.  
     
     
         64 . The apparatus of  claim 63  further including a latch releasably latching said another packer onto said mandrel.  
     
     
         65 . An apparatus for treating a formation adjacent a casing extending from the surface into a well, comprising: 
 a coiled tubing having a flowbore and at least one conductor supported by a wall of said coiled tubing;    a mandrel having a packer mounted thereon and a port in fluid communication with a flowpassage through said mandrel and with said flowbore of said coiled tubing;    a pressure sensor to detect downhole pressure, said pressure sensor transmitting through said conductor to the surface signals that are representative of the downhole pressure;    said pressure sensor and mandrel being supported by said coiled tubing.    
     
     
         66 . The apparatus of  claim 22  wherein said sensor comprises a tilt meter in said bottom hole assembly coupled to said surface controller via said conductors.  
     
     
         67 . The method of  claim 33  further comprising: 
 providing a tilt meter in said tubing string;  
 transmitting to the surface the data sensed by the tilt meter via the conductors in the tubing string.  
 
     
     
         68 . The method of  claim 67  further comprising: 
 evaluating the data transmitted by the tilt sensor;  
 ceasing stimulation when the data transmitted by the tilt meter indicates that predetermined conditions have occurred.