ELASTOMER ALLOY FOR INTELLIGENT SAND MANAGEMENT
20230416594 ยท 2023-12-28
Inventors
- Jinglei Xiang (Lawrence, KS, US)
- Jason Holzmueller (Lawrence, KS, US)
- Xiaohong Ren (Sugar Land, TX, US)
- Jushik Yun (Sugar Land, TX, US)
Cpc classification
E21B43/103
FIXED CONSTRUCTIONS
C08J2315/00
CHEMISTRY; METALLURGY
E21B43/082
FIXED CONSTRUCTIONS
C08L2201/08
CHEMISTRY; METALLURGY
C08L2205/06
CHEMISTRY; METALLURGY
C08J2203/04
CHEMISTRY; METALLURGY
E21B2200/08
FIXED CONSTRUCTIONS
C08J9/0061
CHEMISTRY; METALLURGY
C08J2203/02
CHEMISTRY; METALLURGY
International classification
C08J9/10
CHEMISTRY; METALLURGY
C08J9/00
CHEMISTRY; METALLURGY
E21B43/10
FIXED CONSTRUCTIONS
Abstract
An elastomer alloy includes a base polymer including hydrogenated nitrile butadiene rubber (HNBR) and at least one secondary polymer, which is at least one of paraffin wax, low-density polyethylene (LDPE), linear low-density polyethylene (LLDPE), high-density polyethylene (HDPE), and a plastomer. The base polymer and the at least one secondary polymer are blended into a polymer matrix. The elastomer alloy also includes a plurality of smart fillers dispersed within the polymer matrix, at least one chemical foaming agent, and a curing activator.
Claims
1. An elastomer alloy, comprising: a base polymer comprising hydrogenated nitrile butadiene rubber (HNBR); at least one secondary polymer selected from the group consisting of: paraffin wax; low-density polyethylene (LDPE); linear low-density polyethylene (LLDPE); high-density polyethylene (HDPE); and a plastomer, wherein the base polymer and the at least one secondary polymer are blended into a polymer matrix; a plurality of smart fillers dispersed within the polymer matrix; at least one chemical foaming agent; and a curing activator.
2. The elastomer alloy of claim 1, wherein the plurality of smart fillers comprises at least one selected from the group consisting of: a swellable filler; and a reinforcing filler.
3. The elastomer alloy of claim 2, wherein the swellable filler comprises at least one selected from the group consisting of: a super absorbent polymer (SAP); and MgO.
4. The elastomer alloy of claim 2, wherein the reinforcing filler comprises at least one selected from the group consisting of: Portland cement, aluminous cement, fly ash, slag cement, MgO, ZnO, Ca(OH).sub.2, ZnCl.sub.2, MgCl.sub.2, CaCl.sub.2), CaCO.sub.3, Na.sub.2CO.sub.3, and K.sub.2CO.sub.3.
5. The elastomer alloy of claim 1, further comprising an antioxidant.
6. The elastomer alloy of claim 1, further comprising a process aid.
7. The elastomer alloy of claim 1, wherein the at least one chemical foaming agent is at least one selected from the group consisting of: azodiacarbonamide; and sodium bicarbonate.
8. The elastomer alloy of claim 1, wherein the curing activator comprises at least one selected from the group consisting of: sulfur; and peroxide.
9. The elastomer alloy of claim 1, wherein the elastomer alloy is an open cell foam.
10. The elastomer alloy of claim 1, wherein a permeability coefficient of the elastomer alloy is greater than 10 Darcy.
11. The elastomer alloy of claim 1, wherein a linear expansion ratio in air at about 105 C. in a thickness direction of the elastomer alloy is greater than 20%.
12. The elastomer alloy of claim 1, wherein a linear expansion ratio in a hydrocarbon oil at about 105 C. in a thickness direction of the elastomer alloy is greater than 20%.
13. A sand screen apparatus for use in a downhole operation for hydrocarbon recovery, comprising: the elastomer alloy of claim 1 having a compressed state and an expanded state; a mechanical retainer that compresses the elastomer alloy in the compressed state, wherein the plurality of smart fillers reacts with the polymer matrix in the expanded state after exposure to a wellbore condition.
14. The apparatus of claim 13, wherein the mechanical retainer is a degradable polymeric wrapping tape.
15. The apparatus of claim 14, wherein the wellbore condition causes the degradable polymeric wrapping tape to dissolve.
16. The apparatus of claim 13, wherein the wellbore condition causes the mechanical retainer to release from the elastomer alloy.
17. The apparatus of claim 13, wherein the elastomer alloy conforms to a wellbore in the expanded state.
18. A well completion method, comprising: covering at least one base pipe with the elastomer alloy of claim 1; compressing the elastomer alloy with a mechanical retainer; running the base pipe to a location in a wellbore; expanding the elastomer alloy; conforming the elastomer alloy to a wall of the wellbore; filtering fluids through the elastomer alloy to the base pipe; detaching the elastomer alloy from the base pipe; and lifting the base pipe out of the wellbore.
19. The method of claim 18, wherein the one or the plurality of smart fillers comprises at least one a swellable filler and a reinforcing filler.
20. (canceled)
21. (canceled)
22. The method of claim 18, wherein the expanding step comprises releasing the mechanical retainer.
23. (canceled)
24. (canceled)
25. (canceled)
26. (canceled)
27. (canceled)
28. (canceled)
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] Certain embodiments of the disclosure will hereafter be described with reference to the accompanying drawings, wherein like reference numerals denote like elements. It should be understood, however, that the accompanying figures illustrate the various implementations described herein and are not meant to limit the scope of various technologies described herein, and:
[0010]
[0011]
[0012]
[0013]
[0014]
[0015]
[0016]
[0017]
[0018]
DETAILED DESCRIPTION
[0019] In the following description, numerous details are set forth to provide an understanding of some embodiments of the present disclosure. However, it will be understood by those of ordinary skill in the art that the system and/or methodology may be practiced without these details and that numerous variations or modifications from the described embodiments may be possible.
[0020] In the specification and appended claims: the terms up and down, upper and lower, upwardly and downwardly, upstream and downstream, uphole and downhole, above and below, and other like terms indicating relative positions above or below a given point or element are used in this description to more clearly describe some embodiments of the disclosure.
[0021] The present disclosure generally relates to making and using an elastomer composite for sand control applications. More specifically, one or more embodiments of the present disclosure relate to an elastomer alloy that is able to expand from a compacted or compressed configuration once deployed downhole to conform to an irregularly shaped wellbore for sand control operations. Without the need for additional activation fluids, the elastomer alloy according to one or more embodiments of the present disclosure is much safer than conventional TPU materials. Moreover, the elastomer alloy according to one or more embodiments of the present disclosure also provides excellent thermal stability allowing it to be used at much higher temperatures, up to 150 C. for example, for long-term applications. In contrast, conventional TPU materials are only operable up to 85 C. As further described below, the elastomer alloy according to one or more embodiments of the present disclosure exhibits permeability, robustness, and an expansion ratio that are favorable for sand control operations.
[0022] Referring now to
[0023] Still referring to
[0024] To control the rate of swell of the elastomer alloy due to swellable smart fillers, salt may be used to balance the osmotic pressure differential that might exist in a downhole condition. If the osmotic pressure is too high, the rate of swell will be excessive, and the structure of the elastomer may be damaged. In one or more embodiments of the present disclosure, micro-sized fine salt may be used in the formulation, and the salt may also act as a secondary swelling agent to increase the water uptake by the elastomer alloy.
[0025] As previously described, MgO may also be used as a swellable filler in one or more embodiments of the present disclosure. For example, Nalco D176 is an MgO high temperature expanding additive that reacts with water to form a crosslinked micro domain to stiffen the elastomer alloy according to one or more embodiments of the present disclosure. The reaction rate depends on the pH, temperature, pressure, and the polymer matrix of the elastomer alloy. In particular, MgO may be important for the elastomer alloy according to one or more embodiments of the present disclosure to increase the hardness of the elastomer with time so that the sand screen does not easily deform from differential pressure that may build up across the filter membrane during operation.
[0026] The SAPs that may be used in accordance with one or more embodiments of the present disclosure include cross-linked forms of polyacrylate (acrylic acid and acrylamide), polyvinyl alcohol, poly(ethylene oxide), starch-acrylate copolymer, carboxymethyl cellulose, and other hydrophilic swellable polymers. As understood by those having skill in the art, the degree of swelling and the swelling rate of SAPs depend on the type of cross-linked polymer, the conditions of the water with respect to pH, salinity, temperature, and pressure, the duration of immersion in a solution, and the design of the samples.
[0027] In addition to the swellable smart filler, the plurality of smart fillers may include at least one reinforcing smart filler according to one or more embodiments of the present also disclosure. Examples of a reinforcing smart filler according to one or more embodiments of the present disclosure include Portland cement, aluminous cement, fly ash, slag cement, MgO, ZnO, Ca(OH).sub.2, ZnCl.sub.2, MgCl.sub.2, CaCl.sub.2, CaCO.sub.3, Na.sub.2CO.sub.3, and K.sub.2CO.sub.3, for example.
[0028] Still referring to
[0029] Still referring to
[0030] Still referring to
[0031] In an example for making an elastomer alloy for a swellable sand screen according to one or more embodiments of the present disclosure, about 5-15 parts per hundred of rubber (PHR) of sodium bicarbonate is incorporated with about 1-5 PHR of azo-based organic foaming agent in the presence of 0.5-1.5 PHR curing activator such as Rhenogran Geniplex-70 in a sulfur cured formulation. Specifically, Geniplex-70 is a zinc dicyanato diamine based inorganic isocyanate that can be used to activate sulfur curing and decomposition of an azo foaming agent during the foaming and curing reaction steps (S18, S20) of the method according to one or more embodiments of the present disclosure.
[0032] To initiate sulfur curing, elemental sulfur or sulfur donors are needed. In one or more embodiments of the present disclosure, a sulfur donor is selected for use over elemental sulfur insofar as sulfur donors react to contribute primarily mono and disulphidic bridges that have much higher heat resistance to a polysulphidic bridge formed by elemental sulfur. According to one or more embodiments of the present disclosure, Rhenogran CLD-80, a sulfur donor that does not generate carcinogenic N-nitrosamines during vulcanization, is used for example. Moreover, when Rhenogran CLD-80 is used as the sulfur donor, the resulting vulcanizates do not show any blooming. In a method according to one or more embodiments of the present disclosure, to control the rate of curing and the state of curing, primary and secondary accelerators such as thiurams (tetramethylthiuram disulfide (TMTD), tetraethylthiuram disulfide (TETD), etc.), thiazoles (zinc salt of 2-mercaptobenzothiazole (ZMBT), 2-mercaptobenzothiazole (MBT), 2,2-benzothiazolyl disulfide (MBTS), etc.) or sulfonamides (carboxybenzenesulfonamide (CBS), N-tert-butyl-benzothiazole sulfonamide (TBBS), N,N-Dicyclohexyl-2-benzothiazolsulfene amide (DCBS), etc.) may be used to balance the reaction speed (scorch time) and curing time. In this example, secondary accelerators such as MBTS may be used to provide scorch resistance and to delay the reaction of curing to slightly trail behind the reaction of blowing, which facilitates creation of the open cell structure within the polymer matrix (S22). According to one or more embodiments of the present disclosure, the curing reaction may trail behind the blowing or foaming reaction by about 15 minutes, 10 minutes, 5 minutes, 2 minutes, 1 minute, 30 seconds, 20 seconds, 10 seconds, 5 seconds, 3 seconds, 2 seconds, or 1 second, for example.
[0033] Instead of using a curing activator that includes sulfur for sulfur curing as previously described with respect to steps S16 and S20 in a method according to one or more embodiments of the present disclosure, a curing activator that includes peroxide for peroxide curing may be used in a method according to one or more embodiments of the present disclosure. For example, dicumyl peroxide may be used as the curing activator to facilitate peroxide curing according to one or more embodiments of the present disclosure. For example,
[0034] Moreover, elastomer alloys cured by peroxide and sulfur according to one or more embodiments of the present disclosure may have very different properties including modulus and elongation at break. For example, in one or more embodiments of the present disclosure, the sulfur cured elastomer alloy may have a much higher elongation at break than a similarly processed peroxide cured elastomer alloy due in part to the short and more flexible disulphidic bond that forms during sulfur curing in contrast with the short and rigid CC bond that forms during peroxide curing. The more flexible and soft nature of SS bonds of the sulfur cured elastomer alloy may allow gases to escape easier than the more rigid and short CC bonds of the peroxide cured elastomer alloy. As such, the sulfur cured elastomer alloy according to one or more embodiments of the present disclosure may have a more porous open cell structure after the curing reaction is completed.
[0035] Referring now to
[0036] Moreover, during a permeability test, the sulfur cured elastomer alloy of
[0037] In addition to the above, the elastomer alloy according to one or more embodiments of the present disclosure may include an antioxidant, which may improve the ageing properties of the rubber. While a downhole environment may be depleted of free oxygen, dissolved oxygen could still exist and attack the polymer sand screen, causing degradation, oxidation, and embrittlement of the material at an elevated temperature. Types of antioxidants that may be used in the elastomer alloy according to one or more embodiments of the present disclosure include an amine and/or imidazole based compound such as VANOX CDPA and ZMTI, which may work synergistically to improve the overall heat aging properties of the elastomer alloy.
[0038] In addition to the above, the elastomer alloy according to one or more embodiments of the present disclosure may include a process aid, which may be an oil or dry liquid concentrate compounded into the elastomer alloy to improve processability by lowering the viscosity of the elastomer alloy. Types of process aids that are compatible with nitrile based compounds, such as the elastomer alloy according to one or more embodiments of the present disclosure, include Paraplex G-25, Plasthall TOTM, Plasthall P-7092, Hallstar Dioplex 100, and Paraplex G-57, for example.
[0039] Referring now to
[0040] Referring now to
[0041] Referring now to
[0042] Of note, the expansion ratio in air at 105 C. in the thickness direction of the elastomer alloy 10 sample of
[0043] Referring now to
[0044] Still referring to
[0045] Advantageously, blending the HNBR base polymer and at least one secondary polymer into the polymer matrix creates an elastomer alloy having an open cell structure that exhibits higher permeability than elastomers that only include the HNBR as the base polymer in the polymer matrix, for example. The elastomer alloys according to one or more embodiments of the present disclosure may also exhibit increased stiffness, apart from any reinforcing smart fillers, over elastomers having HNBR as the base polymer alone. Such increased stiffness improves the robustness and the durability of the elastomer alloy during running in hole, for example. Moreover, the elastomer alloy according to one or more embodiments of the present disclosure, exhibits a superior expansion ratio through heat activation over elastomers having HNBR as the base polymer alone.
[0046] Language of degree used herein, such as the terms approximately, about, generally, and substantially as used herein represent a value, amount, or characteristic close to the stated value, amount, or characteristic that still performs a desired function or achieves a desired result. For example, the terms approximately, about, generally, and substantially may refer to an amount that is within less than 10% of, within less than 5% of, within less than 1% of, within less than 0.1% of, and/or within less than 0.01% of the stated amount. As another example, in certain embodiments, the terms generally parallel and substantially parallel or generally perpendicular and substantially perpendicular refer to a value, amount, or characteristic that departs from exactly parallel or perpendicular, respectively, by less than or equal to 15 degrees, 10 degrees, 5 degrees, 3 degrees, 1 degree, or 0.1 degree.
[0047] Although a few embodiments of the disclosure have been described in detail above, those of ordinary skill in the art will readily appreciate that many modifications are possible without materially departing from the teachings of this disclosure. Accordingly, such modifications are intended to be included within the scope of this disclosure as defined in the claims.