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EP-4584471-B1 - METHOD FOR DOWNHOLE CHEMICAL STORAGE FOR WELL MITIGATION AND RESERVOIR TREATMENTS

EP4584471B1EP 4584471 B1EP4584471 B1EP 4584471B1EP-4584471-B1

Inventors

  • ALALI, Eyad, Ali
  • BATAWEEL, Mohammed, Abdullah
  • KALGAONKAR, Rajendra, Arunkumar
  • ARAMCO SERVICES COMPANY

Dates

Publication Date
20260513
Application Date
20230907

Claims (15)

  1. A method, comprising: providing a well (200) extending underground from a surface; using radial drilling to drill a primary tunnel (210) extending in an outwardly direction from the well at a first axial location along the well; installing a chemical storage assembly in the primary tunnel, wherein the chemical storage assembly comprises chemicals stored in the chemical storage assembly; drilling a secondary tunnel (212) extending from the well at a second axial location along the main well; installing a power source (228) in the secondary tunnel; connecting the power source to the chemical storage assembly; and ejecting the chemicals from the chemical storage assembly into the well.
  2. The method of claim 1, wherein the chemical storage assembly further comprises a pill capsule containing the chemicals.
  3. The method of claim 1 or 2, wherein the ejecting of the chemicals is triggered by a change in a downhole environmental condition.
  4. The method of claim 1, further comprising: pulling the chemical storage assembly out of the primary tunnel after ejecting the chemicals to remove the chemical storage assembly; and circulating brine through the well as the chemical storage assembly is removed.
  5. The method of any one of claims 1 to 4, wherein the radial drilling comprises using a whipstock to orient a radial drilling bit in the outwardly direction from the well as the radial drilling bit drills the primary tunnel, wherein the method further comprises: rotating the whipstock in the well to orient the radial drilling bit in a second outwardly direction from the well; and drilling an additional primary tunnel in the second outwardly direction from the well at the first axial location.
  6. A method, comprising: providing a well extending underground from a surface; drilling a primary tunnel extending a length from the well in an outwardly direction from the well; installing a chemical storage assembly in the primary tunnel; drilling a secondary tunnel extending outwardly from the well at a different axial location than the primary tunnel; installing a chemical storage compartment in the secondary tunnel; connecting the chemical storage compartment to a dispensing mechanism in the chemical storage assembly in the primary tunnel; moving a downhole tool through the well and past the primary tunnel to perform a well operation; and ejecting chemicals from the chemical storage assembly during or after performing the well operation.
  7. The method of claim 6, wherein the well operation is a workover operation comprising extending a production string through the main well.
  8. The method of any one of claims 6 to 7, further comprising: drilling a secondary tunnel extending outwardly from the well at a different axial location than the primary tunnel; installing a power source in the secondary tunnel; connecting the power source to a controller in the chemical storage assembly; and using the controller to eject controlled dosages of the chemicals from the chemical storage assembly.
  9. A system, comprising: a well extending through an underground formation; a primary tunnel extending a length outwardly from the well at a first axial location along the well; a chemical storage assembly installed in the primary tunnel; a secondary tunnel extending outwardly from the well; and a power source installed in the secondary tunnel, wherein the power source is connected to the chemical storage assembly.
  10. The system of claim 9, wherein the well is a branch well extending from a main well, and the main well extends underground from a surface.
  11. The system of claim 9 or 10, wherein the chemical storage assembly comprises: a chemical storage compartment containing the chemicals; and a pump in fluid communication with the container.
  12. The system of any of claims 9 to 11, further comprising an additional primary tunnel at the first axial location extending outwardly from the well in a different direction from the primary tunnel.
  13. The system of any of claims 9 to 12, further comprising: an additional tunnel extending outwardly from the well; and a chemical storage compartment disposed in the additional tunnel, wherein the chemical storage compartment is fluidly connected to the chemical storage assembly in the tunnel.
  14. The system of any one of claims 9 to 13, wherein the primary tunnel and the secondary tunnel have diameters that are less than 7 inches.
  15. The system of any one of claims 9 to 14, wherein the primary tunnel and the secondary tunnel extend outwardly from a horizontal section of the well.

Description

BACKGROUND Wells are drilled into subsurface formations to produce valuable resources, such as oil and gas. A well is typically drilled by moving a rotating drill bit attached at an end of a drill string through the earth to form a wellbore. The drill string and attached drill bit may be rotated and extended underground using rig equipment at the surface of the well. Drilling fluid, also referred to as "drilling mud" or simply "mud," is used to facilitate drilling wellbores into the earth. As the drill string and bit are rotated to drill the wellbore, one or more mud pumps at the surface of the well circulates drilling fluid through the well, where the drilling fluid may flow from the surface of the well, through the drill string, out the end of the drill string, and back up the well through an annulus formed around the outside of the drill string to return to the surface of the well. As the wellbore is formed, strings of casing and/or liner may be installed to line the wellbore wall. Casing may be installed in the well by pumping cement into an annulus formed between the casing string and the wellbore wall. Wells may be drilled to extend vertically, horizontally, or other direction through the earth. Radial drilling refers to a method of drilling small generally radially extending tunnels (typically a few inches, an inch corresponding to 2,54 cm, in diameter) extending from a main well into the formation strata (typically to a maximum of about 91,44 - 121,92 m: 300-400 feet). Radial drilling is commonly used to access trapped oil or gas in the near-well formation and stimulate production. Radial drilling tools are often deployed through the main well using coiled tubing, although slickline has also been used. Unlike drill string, which is made of multiple rigid sections of pipe that are threaded together in an end-to-end fashion, coiled tubing is a long, continuous length of pipe that is wound on a spool to be stored or transported and then straightened to be pushed into a well. Radial drilling may include radial jet drilling, where a high-pressure fluid is jetted through radial drilling tools to penetrate and form the tunnel, or mechanical radial drilling, where a radial drilling bit (rotated by a downhole mud motor) may be used to drill the tunnel. When radially drilling from a cased well, radial drilling may include a combination of milling through the casing with a radial drilling bit and jetting the tunnel from the milled hole in the casing. Radial drilling tools may vary depending on the radial drilling technique being used and may include, for example, a downhole mud motor, a jetting nozzle and hose, a milling bit, and others. For example, a typical radial drilling system 100 is shown in FIG. 1, which may be used to drill a tunnel 101 extending radially from a cased main well 102 through a formation 103. A whipstock 104 (also referred to as a deflector shoe) may be lowered into the main well 102 via a tubing 105. One or more centralizers 109 may be positioned around the tubing 105 to keep the whipstock 104 centered within the tubing 105. Coiled tubing 106 having radial drilling equipment attached at the end may be extended through the tubing 105. The radial drilling equipment may include a downhole mud motor 107 and a radial drilling bit 108 rotatable by the mud motor 107 via a flexible pipe 110. As the mud motor 107 rotates the radial drilling bit 108, the radial drilling bit 108 may be directed through the whipstock 104 at a turn 111 ("heel") to contact and cut through the main well casing into the formation 103 around the main well 102. In radial jet drilling operations, the radial drilling bit 108 may be removed after initiating the tunnel 101 from the main well 102, and a high-pressure nozzle and hose may be extended through the whipstock 104 to eject a high-pressure fluid to hydraulically impact and extend the tunnel 101 into the formation 103. Radial drilling is different from coiled-tubing sidetracking procedures and conventional horizontal drilling, which may be used to drill branch wellbores, e.g., for multilateral wells. A multilateral well is a well with two or more branch wells drill from a main well that may allow one well to produce from several reservoirs via the branch wells (rather than drilling multiple separate wells from the surface to the different reservoir areas). A major difference between radial drilling and conventional sidetracking or horizontal drilling is that radial drilling generally operates at a much smaller scale, e.g., 2 to 4 orders of magnitude smaller than conventional sidetracking and horizontal drilling. For example, branch wellbores (sometimes referred to as laterals) may be drilled at an angle from the main well around a heel that is typically hundreds or thousands of feet ( a foot corresponding to 30,48 cm) in length. In contrast, radial drilling typically involves a change of direction with a tighter radius of curvature that occurs entirely around a whipst