# US 2023/0272702 A1 · System and method of using a thermoplastic casing in a wellbore > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2023/0272702 A1 - Document ID: US20230272702A1 - Status: Published application - Kind: A1 - Application number: 18/115,387 - Filed: 2023-02-28 - Published: 2023-08-31 - Earliest claimed: 2022-02-28 - Assignees: Ur-Energy USA Inc. - Applicants: Ur-Energy USA Inc. - Inventors: Steven M. Hatten; John W. Cash - Web page: https://patentgrep.com/patent/US20230272702A1 ## CPC - E21B 43/28: Dissolving minerals other than hydrocarbons, e.g. by an alkaline or acid leaching agent (E21B43/241 takes precedence) - E21B 17/1078: {Stabilisers or centralisers for casing, tubing or drill pipes (E21B17/1007 - E21B17/1064 take precedence)} - E21B 29/002: {Cutting, e.g. milling, a pipe with a cutter rotating along the circumference of the pipe} - E21B 33/14: for cementing casings into boreholes - E21B 43/04: Gravelling of wells - E21B 43/08: Screens or liners {(expandable screens or liners E21B43/108)} - E21B 43/10: Setting of casings, screens, liners {or the like} in wells - E21B 43/30: Specific pattern of wells, e.g. optimising the spacing of wells - E21B 7/28: Enlarging drilled holes, e.g. by counterboring - E21B: EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS ## Abstract Systems and methods for using a continuous, thermoplastic tubing as a casing in a wellbore are provided. A continuous, thermoplastic tubing can be a high density polyethylene (HDPE) material that is stored in a coiled manner on a spindle. A screen can be attached to an end of the casing, and a tremie line can be selectively connected to the screen to inject gravel and cement downhole to pack the screen in place and grout the casing in place in the wellbore. The use of a continuous, thermoplastic tubing removes joints from the casing to improve performance, and such tubing is more readily available and cheaper than alternatives among other benefits described herein. ## Claims ### Claim 1 A method of installing a casing composed of a continuous, non-jointed, thermoplastic tubing in a wellbore, comprising: providing a coil of the tubing; attaching a screen to an end of the tubing; uncoiling the tubing and lowering the tubing and a tremie line into the wellbore until the screen reaches a predetermined depth; raising the tubing and the tremie line by a predetermined distance to straighten and centralize the tubing within the wellbore; injecting gravel through the tremie line to surround the screen with gravel as the tremie line is retrieved from the wellbore; injecting cement through the tremie line to fill an annular space between the tubing and the wellbore as the tremie line is further retrieved from the wellbore; and removing the tremie line from the wellbore and cutting the tubing leaving the casing without joints from a surface of the wellbore to the screen. ### Claim 2 (depends on 1) The method of claim 1, further comprising selectively connecting the tremie line to the screen prior to lowering the tubing and the tremie line into the wellbore, wherein the selective connection between the tremie line and the screen is offset from a lower end of the screen by between 1 foot and 3 feet. ### Claim 3 (depends on 1) The method of claim 1, further comprising sealing the end of the tubing and introducing a fluid into an interior volume of the tubing to increase a pressure required to collapse the tubing during injection of cement into the annular space. ### Claim 4 (depends on 1) The method of claim 1, further comprising drilling the wellbore, wherein the inner diameter of the wellbore is between 150% and 300% of the outer diameter of the casing. ### Claim 5 (depends on 1) The method of claim 1, further comprising depositing an impermeable layer through the tremie line between the gravel and the cement. ### Claim 6 (depends on 1) The method of claim 1, further comprising attaching a plurality of centralizers to the tubing as the tubing and the tremie line are lowered into the wellbore, wherein a lowest centralizer of the plurality of centralizers is offset from the screen by approximately 2 feet, and wherein two centralizers of the plurality of centralizers are offset from each other by approximately 40 feet. ### Claim 7 (depends on 1) The method of claim 1, further comprising under-reaming a portion of the wellbore at the predetermined depth. ### Claim 8 (depends on 1) The method of claim 1, wherein the tubing is made from one of polyethylene (PE), polyvinyl chloride (PVC), polypropylene (PP), polyvinylidene fluoride (PVDF), thermoplastic elastomer (TPE), Tygon®, Nylon, polytetrafluoroethylene (PTFE), or polyurethane. ### Claim 9 A system for using a continuous, non-jointed thermoplastic casing in a wellbore, comprising: a screen connected to an end of the casing, wherein the casing is stored in a coil; a tremie line is selectively connected to the screen at a location above a lower end of the screen; wherein, in a first mode of operation, the casing is uncoiled and the casing and the tremie line are lowered into the wellbore until the screen reaches a geologic formation, wherein the wellbore has an inner diameter that is larger than an outer diameter of the casing to allow for the tremie line to provide a grout or cement seal; and wherein, in a second mode of operation, the tremie line is disconnected from the screen, and at least one of gravel or cement flows through the tremie line to pack the screen and grout the casing as the tremie line is removed from the wellbore. ### Claim 10 (depends on 9) The system of claim 9, wherein the casing is made from one of polyethylene (PE), polyvinyl chloride (PVC), polypropylene (PP), polyvinylidene fluoride (PVDF), thermoplastic elastomer (TPE), Tygon®, Nylon, polytetrafluoroethylene (PTFE), or polyurethane. ### Claim 11 (depends on 9) The system of claim 9, wherein an outer diameter of the tremie line is between 30% and 110% of the outer diameter of the casing. ### Claim 12 (depends on 9) The system of claim 9, wherein the inner diameter of the wellbore is between 150% and 300% of the outer diameter of the casing. ### Claim 13 (depends on 9) The system of claim 9, further comprising a plurality of centralizers attached to the casing, wherein a lowest centralizer of the plurality of centralizers is offset from the screen by approximately 2 feet, and wherein two centralizers of the plurality of centralizers are offset from each other by approximately 40 feet. ### Claim 14 (depends on 9) The system of claim 9, wherein the tremie line is a continuous, non-jointed, thermoplastic tubing. ### Claim 15 A method of extracting an ore from a geologic formation, comprising: lowering a casing and an injection screen which is connected to an end of the casing into a wellbore; sealing a distal end of the casing and pressurizing an interior volume of the casing with a fluid as the casing is cemented in place in the wellbore to form an injection well; providing a production well having a casing and a production screen engaged with the casing of the production well; injecting a lixiviant fluid into the injection well where the lixiviant fluid travels through the casing of the injection well, through the injection screen, and into the geologic formation; receiving a combination of the lixiviant fluid and the ore from the geologic formation through the production screen of the production well; and drawing the combination of the lixiviant fluid and the ore through the casing of the production well and out of the production well. ### Claim 16 (depends on 15) The method of claim 15, wherein a diameter of the casing of the production well is greater than a diameter of the casing of the injection well. ### Claim 17 (depends on 15) The method of claim 15, wherein the injection well is one of a plurality of injection wells arranged in a hexagonal pattern with an injection well located at each corner of the hexagonal pattern; and wherein the production well is located within the hexagonal pattern and is located between six injection wells of the plurality of injection wells. ### Claim 18 (depends on 15) The method of claim 15, wherein providing the injection well comprises: uncoiling a continuous, non-jointed, thermoplastic tubing to serve as the casing of the injection well, and lowering the tubing and a tremie line into the wellbore until the injection screen reaches a predetermined depth; raising the tubing and the tremie line by a predetermined distance to straighten and centralize the tubing within the wellbore; injecting gravel through the tremie line to surround the injection screen with gravel as the tremie line is retrieved from the wellbore; injecting cement through the tremie line to fill an annular space between the tubing and the wellbore as the tremie line is further retrieved from the wellbore; and removing the tremie line from the wellbore and cutting the tubing leaving the casing without joints from a surface of the wellbore to the injection screen. ### Claim 19 (depends on 15) The method of claim 15, further comprising drilling a wellbore, wherein an inner diameter of the wellbore of the injection well is between 150% and 300% of an outer diameter of the casing of the injection well. ### Claim 20 (depends on 15) The method of claim 15, wherein the casing of the injection well and the casing of the production well are each made from one of polyethylene (PE), polyvinyl chloride (PVC), polypropylene (PP), polyvinylidene fluoride (PVDF), thermoplastic elastomer (TPE), Tygon®, Nylon, polytetrafluoroethylene (PTFE), or polyurethane.