System and Method of Liquefying a Heavy Oil Formation for Enhanced Hydrocarbon Production

Abstract

A system and method of liquefying a heavy oil formation to enhance oil production in a well, by inducing shear stress reversal within the formation by a plurality of expanding/contracting bladders in contact with the formation. The induced liquefaction enables formation materials and fluids to flow into the well and thus initiate and propagate the CHOPS (Cold Heavy Oil Production System) process, and thereby enhancing the hydrocarbon production of the well.

1 . A system for producing hydrocarbons from a formation at a depth horizon comprising:
 a. a cyclic shear stress reversal device in contact with the formation for applying cyclical shear stress reversal to the formation to induce liquefaction of the formation;   b. an inlet connecting the formation to the cyclic shear stress reversal device; and   c. an extraction device for drawing formation materials and fluids from the formation into the inlet.   
     
     
         2 . The system of  claim 1 , wherein the cyclic shear stress reversal device comprises a plurality of cyclically expanding/contracting bladders to load the formation under a near zero volume change condition to induce liquefaction of the formation. 
     
     
         3 . The system of  claim 1 , wherein the cyclic shear stress reversal device is self-boring down to the required formation depth horizon. 
     
     
         4 . The system of  claim 1 , wherein the cyclic shear stress reversal device is driven down to the required formation depth horizon. 
     
     
         5 . The system of  claim 1 , wherein the cyclic shear stress reversal device is inserted into a pre-drilled borehole down to the required formation depth horizon. 
     
     
         6 . The system of  claim 1 , wherein the cyclic shear stress reversal device is inserted into an existing well, in which the existing casing has been removed across the formation depth horizon. 
     
     
         7 . The system of  claim 2 , wherein the cyclic shear stress reversal device comprises a piston in a fluid cylinder connected to the plurality of bladders, and movement of the piston extracts fluid from contracting bladders and injects fluid into expanding bladders to ensure the formation is cyclically loaded under near zero volume change condition. 
     
     
         8 . The system of  claim 2 , wherein a pore water pressure sensor obtains data measurements for formation pore pressure response to cyclic loading, and other sensors measure the rate of change of expansion/contraction of the bladders, and the fluid pressures inside of the bladders. 
     
     
         9 . The system of  claim 2 , wherein the cyclic shear stress reversal device consists of two expansion/contraction bladders. 
     
     
         10 . The system of  claim 1 , wherein the extraction device extracts formation material and formation fluids from the formation during or immediately after cyclic loading of the formation by the cyclic shear stress reversal device. 
     
     
         11 . A system of  claim 10 , wherein the extraction device is a piston sampling device. 
     
     
         12 . A system of  claim 10 , wherein the extraction device is a progressive cavity pump. 
     
     
         13 . A system of  claim 10 , wherein the extraction device further includes a pump that injects a foaming fluid into the formation. 
     
     
         14 . The system of  claim 1 , wherein the cyclic shear stress reversal device is removed from the well, and a perforated liner is placed across the formation horizon. 
     
     
         15 . The system of  claim 14 , wherein a pump is inserted in the well and formation materials and fluids are extracted from the well via production tubing. 
     
     
         16 . The system of  claim 15 , wherein the pump is of the progressive cavity type. 
     
     
         17 . A method for producing hydrocarbons from a formation at a depth horizon comprising:
 a. Cyclically applying shear stress reversal loading to the formation under a near zero volume change condition to induce liquefaction of the formation; and   b. extracting formation materials and fluids from the formation.   
     
     
         18 . The method of  claim 17 , wherein the method includes placing a cyclic shear stress reversal device within the formation for cyclically applying shear stress reversal loading to the formation. 
     
     
         19 . The method of  claim 18 , wherein the cyclic shear stress reversal device comprises a plurality of cyclically expanding/contracting bladders to load the formation under a near zero volume change condition to induce liquefaction of the formation. 
     
     
         20 . The method of  claim 18 , wherein placing the cyclic shear stress reversal device includes the cyclic shear stress reversal device being self-boring and boring down to the required formation depth horizon. 
     
     
         21 . The method of  claim 18 , wherein placing the cyclic shear stress reversal device includes driving the cyclical shear stress reversal device down to the required formation depth horizon. 
     
     
         22 . The method of  claim 18 , wherein placing the cyclic shear stress reversal device includes inserting the cyclical shear stress reversal device into a pre-drilled borehole down to the required formation depth horizon. 
     
     
         23 . The method of  claim 18 , wherein placing the cyclic shear stress reversal device includes inserting the cyclical shear stress reversal device into an existing well, in which the existing casing has been removed across the formation depth horizon. 
     
     
         24 . The method of  claim 19 , wherein loading the formation includes alternatively extracting fluid from contracting bladders and injecting fluid into expanding bladders to ensure the formation is cyclically loaded under near zero volume change condition. 
     
     
         25 . The method of  claim 19 , wherein the method further includes measuring a pore water pressure of the formation in response to cyclic loading, measuring the rate of change of expansion/contraction of the bladders, and measuring the fluid pressures inside of the bladders. 
     
     
         26 . The method of  claim 19 , wherein the device consists of two expansion/contraction bladders. 
     
     
         27 . The method of  claim 17 , wherein formation material and formation fluids are extracted from the formation during or immediately after cyclic loading of the formation. 
     
     
         28 . A method of  claim 27 , wherein the method of extracting formation material and fluids is by a piston sampling device. 
     
     
         29 . A method of  claim 27 , wherein the method of extracting formation material and fluids is by a pump, being of the progressive cavity type. 
     
     
         30 . A method of  claim 27 , wherein the method of extracting formation material and fluids is by a foaming fluid injected into the well, with formation material, fluids and foam extracted from the well. 
     
     
         31 . The method of  claim 19 , wherein the bladders are removed from the formation and a perforated liner is placed across the formation horizon. 
     
     
         32 . The method of  claim 31 , wherein a pump is inserted in the well and formation materials and fluids are extracted from the well via production tubing. 
     
     
         33 . The method of  claim 32 , wherein the pump is of the progressive cavity type. 
     
     
         34 . The method of  claim 17 , wherein steam is injected into the formation upon the onset of induced liquefaction of the formation and prior to extraction of formation materials and fluids. 
     
     
         35 . The method of  claim 17 , wherein a vaporized hydrocarbon solvent is injected into the formation upon the onset of induced liquefaction of the formation and prior to extraction of formation materials and fluids. 
     
     
         36 . The method of  claim 35 , wherein the vaporized hydrocarbon solvent is one of a group of ethane, propane, butane or a mixture thereof. 
     
     
         37 . The method of  claim 35 , wherein the injected vaporized hydrocarbon solvent is maintained saturated at or near its dew point.