Cement paste retarder as well as preparation method and application thereof

Abstract

The invention discloses a cement paste retarder as well as a preparation method and application thereof. The cement paste retarder is an organic-inorganic hybrid material formed by an organic material and an inorganic material; the organic material is selected from a substance with a carboxylate radical and / or hydroxyl structure; the inorganic material is selected from a compound with a layered structure. The retarder is a solid retarder after inorganic and organic hybridization, has the characteristics of efficient adsorption of organic materials and filling and enhancement of inorganic materials, and is good in stability and excellent in performance, so that the problems that the retarder is poor in stability, poor in thickening linear relation and slow in top strength development at high temperature and high pressure are solved.

Description

Technical Field

[0001] The present invention relates to the technical field of oilfield chemical additives, and more particularly to a cement slurry retarder and a preparation method and application thereof; still more particularly to an oil well cement slurry retarder and a preparation method and application thereof. Background Art

[0002] In order to meet the needs of cementing construction and control the setting time of cement slurry, it is necessary to add a certain proportion of retarder to the cement slurry to adapt to the requirements of different bottom hole temperatures. Retarder is usually divided into low-temperature, medium-temperature and high-temperature retarders. At present, high-temperature retarders are mainly classified into: (1) lignin sulfonates; (2) cellulose and its derivatives; (3) organic small molecules with special functional groups and structures; (4) inorganic acids, inorganic salts or oxides; (5) synthetic polymers. Inorganic acids, polysaccharides and synthetic polymers are still the most commonly used. These materials are inexpensive, easy to obtain and have good retarding effect. They are very popular among major oil fields and enterprises. However, due to their heterogeneous structure, the use effect varies greatly. They often have the disadvantages of strong selectivity for cement, sensitivity to dosage, lack of high temperature resistance, and slow strength development at the top of a long cementing section with large temperature difference.

[0003] China is welcoming a strategic opportunity period for the parallel development of conventional and unconventional oil and gas. The market scale of deep and ultra-deep well services is growing. Deep and ultra-deep wells have high bottom temperatures, long sealing sections, large temperature differences, and difficulty in building top strength, which has become a bottleneck restricting oil and gas exploration and development. Solving the engineering and technical problems of large temperature differences can start with the optimization of cement slurry systems and cementing processes, but the most fundamental and effective way is to develop high temperature resistant and stable retarder. Summary of the invention

[0004] In order to solve the problems in the prior art, the present invention proposes a cement slurry retarder and its preparation method and application. The present invention develops a new type of oil well cement retarder through an inorganic-organic hybridization method. The retarder of the present invention is a solid retarder after inorganic-organic hybridization, which takes into account the characteristics of efficient adsorption of organic materials and filling and enhancement of inorganic materials, has good stability and excellent performance, thereby solving the problems of poor stability of the retarder under high temperature and high pressure, poor thickening linear relationship and slow development of top strength.

[0005] One of the purposes of the present invention is to provide a cement slurry retarder, which is an organic-inorganic hybrid material formed by an organic material and an inorganic material; the organic material is selected from substances having a carboxylate and / or hydroxyl structure; the inorganic material is selected from compounds having a layered structure.

[0006] In the present invention, the cement slurry retarder is a cement slurry retarder formed by hybridization of inorganic materials and organic materials in an ion-bonded manner.

[0007] In the cement slurry retarder of the present invention, preferably,

[0008] The organic material includes a stabilizer and a coagulant;

[0009] Preferably, the stabilizer is selected from at least one of yellow dextrin and white dextrin; and / or,

[0010] The coagulant is selected from at least one of tartaric acid, sodium glucoheptonate and sodium gluconate;

[0011] More preferably, the coagulant is selected from a mixture of tartaric acid, sodium glucoheptonate and sodium gluconate.

[0012] In the present invention, the tartaric acid in the setting agent plays a role in complexing and adsorbing with calcium ions of the cement slurry to control the setting time of the cement slurry, and can be replaced by sodium glucoheptonate or sodium gluconate, but the effect of using one or both is not as good as the effect of a combination of tartaric acid, sodium glucoheptonate and sodium gluconate.

[0013] In the cement slurry retarder of the present invention, preferably,

[0014] The organic material is loaded into the layered structure of the inorganic material; preferably, the organic material is intercalated into the layered structure of the inorganic material.

[0015] In the cement slurry retarder of the present invention, preferably,

[0016] The mass ratio of the organic material to the inorganic material is 0.4 to 0.7;

[0017] Preferably, the mass ratio of the coagulant to the stabilizer in the organic material is 0.7 to 1.3;

[0018] More preferably,

[0019] In the cement slurry retarder, the content of inorganic material is greater than 61wt%, preferably 64wt% to 70wt%; the content of setting regulator is greater than 11wt%, preferably 16wt% to 21.5wt%; and the rest is stabilizer.

[0020] In the cement slurry retarder of the present invention, preferably,

[0021] The inorganic material is selected from hydrotalcite;

[0022] More preferably, the inorganic material is selected from at least one of calcium aluminum hydrotalcite and calcium magnesium hydrotalcite.

[0023] In the cement slurry retarder of the present invention, inorganic materials such as calcium aluminum hydrotalcite play a role in reinforcing cement paste, and the metal ions in the hydrotalcite have the effect of accelerating the early hydration of cement slurry. In addition, the layered structure can also protect the retarder and improve the temperature resistance of the retarder.

[0024] Further preferably, the hardness of the hydrotalcite is 3.5-4 and the density is 2.7-2.8 g / cm 3 .

[0025] In the cement slurry retarder of the present invention, preferably,

[0026] The stabilizer is 6 to 10 parts by weight;

[0027] Tartaric acid is 3 to 5 parts by weight;

[0028] Sodium glucoheptonate is 1 to 3 parts by weight;

[0029] Sodium gluconate is 0.5 to 3 parts by weight;

[0030] The inorganic material is 25 to 30 parts by weight.

[0031] In the cement slurry retarder of the present invention, preferably,

[0032] 6 to 8 parts by weight of a stabilizer; and / or,

[0033] 3 to 5 parts by weight of tartaric acid; and / or,

[0034] Sodium glucoheptonate is 1 to 2 parts by weight; and / or,

[0035] Sodium gluconate is 0.5 to 1 parts by weight; and / or,

[0036] The inorganic material is 27 to 29 parts by weight.

[0037] The second object of the present invention is to provide a method for preparing a cement slurry retarder, comprising the following steps:

[0038] Dry-mixing and loading the organic material and the inorganic material to obtain the cement slurry retarder;

[0039] It is preferably used for the preparation of the cement slurry retarder as claimed in any one of the objects of the present invention.

[0040] In the preparation method of the cement slurry retarder of the present invention, preferably,

[0041] When the dry mix is ​​loaded, a planetary ball mill is used for grinding;

[0042] Preferably, the grinding speed is 60 to 180 r / min; and / or,

[0043] Each grinding time is 20 to 40 minutes, and the number of grinding times is 4 times; and / or,

[0044] The grinding balls are made of 3-5 mm zirconium oxide; and / or,

[0045] The mass ratio of the grinding balls to the ground sample is controlled at 8 to 10; and / or,

[0046] The particle size of each material in the organic material is between 180 and 200 meshes.

[0047] The preparation method of the organic material in the present invention is: dry-mix and grind the corresponding components of the organic material to obtain the organic material, preferably dry-mix and grind the stabilizer and the coagulant to obtain the organic material. When dry-mixing and grinding the various substances in the organic material of the present invention, a common mortar is used for grinding, and the large particles are roughly ground until the particle sizes of the various materials in the organic material are roughly the same.

[0048] The third object of the present invention is to provide a cement slurry retarder as described in any one of the objects of the present invention or a cement slurry retarder prepared by the method described in any one of the objects of the present invention for use in the oil field, preferably in oil production cementing construction.

[0049] A fourth object of the present invention is to provide a cement slurry, wherein the cement slurry comprises the cement slurry retarder as described in any one of the objects of the present invention or the cement slurry retarder prepared by the method as described in any one of the objects of the present invention and cement ash;

[0050] Preferably, in the cement slurry, the mass ratio of the added cement slurry retarder to the added cement ash is 1% to 3%:1.

[0051] Most preferably, the technical scheme of the present invention is: to develop a high-temperature oil well cement retarder, wherein the retarder is dry-mixed and ground with organic materials: stabilizer, tartaric acid, sodium glucoheptonic acid and sodium gluconate in a certain proportion under certain temperature conditions; then added to a planetary ball mill for dry mixing and coating together with inorganic functional materials, wherein the inorganic material is calcium aluminum hydrotalcite: white granular, with glass luster, hardness of 3.5-4, density: 2.7-2.8 g / cm 3 The mass ratio of organic and inorganic materials is 1:2, and the hybridization conditions are: planetary ball milling, 60r / min, 30min×4, alternating forward and reverse rotations.

[0052] The endpoints and any values ​​of the scope disclosed in the present invention are not limited to the precise scope or value, and these scopes or values ​​should be understood to include values ​​close to these scopes or values. For numerical ranges, the endpoint values ​​of each scope, the endpoint values ​​of each scope and the individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be regarded as specifically disclosed in this article. Hereinafter, in principle, each technical solution can be combined with each other to obtain a new technical solution, which should also be regarded as specifically disclosed in this article.

[0053] Compared with the prior art, the present invention has the following beneficial effects:

[0054] (1) The preparation process is simple, and the retarder after hybridization is uniform and has good stability;

[0055] (2) Good temperature resistance, able to meet the 160℃ test requirements, and good thickening linear relationship;

[0056] (3) The strength of cement slurry develops rapidly and can adapt to the large temperature difference of 80℃. DETAILED DESCRIPTION

[0057] The present invention is described in detail below in conjunction with specific embodiments. It is necessary to point out that the following embodiments are only used to further illustrate the present invention and cannot be understood as limiting the scope of protection of the present invention. Some non-essential improvements and adjustments made to the present invention by those skilled in the art based on the contents of the present invention still fall within the scope of protection of the present invention.

[0058] It should also be noted that the various specific technical features described in the following specific embodiments can be combined in any suitable manner without contradiction. To avoid unnecessary repetition, the present invention will not further describe various possible combinations.

[0059] In addition, the various embodiments of the present invention may be arbitrarily combined as long as they do not violate the concept of the present invention. The technical solutions thus formed belong to part of the original disclosure of this specification and also fall within the protection scope of the present invention.

[0060] The raw materials used in the examples and comparative examples, unless otherwise specified, are disclosed in the prior art, for example, they can be directly purchased or prepared according to the preparation methods disclosed in the prior art.

[0061] The calcium aluminum hydrotalcite used in the following examples of the present invention has a hardness of 3.7 and a density of 2.75 g / cm 3 .

[0062] The G-grade cement used in the following examples of the present invention was purchased from Sichuan Jiahua Cement Factory, and the fluid loss reducer 1 was purchased from the fluid loss reducer DZJ-Y of Shandong Dezhou Continental Shelf Additive Factory.

[0063] [Example 1]

[0064] Preparation of retarder 1:

[0065] Weigh 7 parts by weight of a stabilizer (yellow dextrin), 4 parts by weight of tartaric acid, 2 parts by weight of sodium gluceptate and 1 part by weight of sodium gluconate, put them into an ordinary mortar and grind them, roughly grind the large particles to about 180-200 mesh, and then put them into a planetary ball mill together with 28 parts by weight of calcium aluminum hydrotalcite. The ball milling parameters are: 60r / min, 30min×4, the grinding balls are 3-5mm zirconium oxide, the mass ratio of the grinding balls to the ground samples is controlled to be 9, and the positive and reverse rotations are performed alternately to obtain the cement slurry retarder of the present invention.

[0066] [Example 2]

[0067] Preparation of retarder 2:

[0068] Weigh 7 parts by weight of a stabilizer (white dextrin), 5 parts by weight of tartaric acid, 2.5 parts by weight of sodium glucoheptonate and 1.5 parts by weight of sodium gluconate, put them into a grinder, grind them to a uniform particle size, and then put them into a planetary ball mill together with 26 parts by weight of calcium aluminum hydrotalcite. The ball milling parameters are the same as in Example 1.

[0069] [Example 3]

[0070] Preparation of retarder 3:

[0071] Weigh 7 parts by weight of stabilizer (yellow dextrin), 3 parts by weight of tartaric acid, 1.5 parts by weight of sodium glucoheptonate and 0.5 parts by weight of sodium gluconate, put them into a grinder, grind them to a uniform particle size, and then put them into a planetary ball mill together with 30 parts by weight of calcium aluminum hydrotalcite. The ball milling parameters are the same as in Example 1.

[0072] [Example 4]

[0073] Preparation of retarder 4:

[0074] Weigh 8 parts by weight of a stabilizer (yellow dextrin), 4 parts by weight of tartaric acid, 2 parts by weight of sodium gluceptate and 1 part by weight of sodium gluconate, put them into a grinder, grind them to a uniform particle size, and then put them into a planetary ball mill together with 27 parts by weight of calcium aluminum hydrotalcite. The ball milling parameters are the same as in Example 1.

[0075] [Example 5]

[0076] Preparation of retarder 5:

[0077] Weigh 6 parts by weight of stabilizer (yellow dextrin), 4 parts by weight of tartaric acid, 2 parts by weight of sodium gluceptate and 1 part by weight of sodium gluconate, put them into a grinder, grind them to a uniform particle size, and then put them into a planetary ball mill together with 29 parts by weight of calcium aluminum hydrotalcite. The ball milling parameters are the same as in Example 1.

[0078] [Comparative Example 1]

[0079] The preparation conditions are basically the same as those in Example 1, except that an equal amount of organic material is used to replace the inorganic material.

[0080] [Comparative Example 2]

[0081] The preparation conditions are basically the same as those in Example 1, except that an equal amount of inorganic material is used to replace the organic material.

[0082] The hybridized retarder was added into the cement slurry system for high temperature and high pressure thickening and strength performance evaluation. The oil well cement test method was carried out in accordance with GB / T19139-2012.

[0083] [Test Example 1]

[0084] Oil well cement slurry system:

[0085] G grade cement (100 parts), silica fume (35 parts), fluid loss reducer 1 (5 parts), retarder (0 parts), tap water (53 parts).

[0086] [Test Example 2]

[0087] Oil well cement slurry system:

[0088] G-grade cement (100 parts), silica fume (35 parts), fluid loss reducer 1 (5 parts), retarder of Example 1 (1.5 parts), tap water (53 parts).

[0089] [Test Example 3]

[0090] Oil well cement slurry system:

[0091] G grade cement (100 parts), silica fume (35 parts), fluid loss reducer 1 (5 parts), retarder of Example 2 (1.5 parts), tap water (53 parts).

[0092] [Test Example 4]

[0093] Oil well cement slurry system:

[0094] G grade cement (100 parts), silica fume (35 parts), fluid loss reducer 1 (5 parts), retarder of Example 3 (1.5 parts), tap water (53 parts).

[0095] [Test Example 5]

[0096] Oil well cement slurry system:

[0097] G-grade cement (100 parts), silica fume (35 parts), fluid loss reducer 1 (5 parts), retarder of Example 4 (1.5 parts), tap water (53 parts)

[0098] [Test Example 6]

[0099] Oil well cement slurry system:

[0100] G grade cement (100 parts), silica fume (35 parts), fluid loss reducer 1 (5 parts), retarder of Example 5 (1.5 parts), tap water (53 parts).

[0101]

Test Example 7

[0102] Oil well cement slurry system:

[0103] G grade cement (100 parts), silica fume (35 parts), fluid loss reducer 1 (5 parts), retarder of comparative example 1 (1.5 parts), tap water (53 parts).

[0104]

Test Example 8

[0105] Oil well cement slurry system:

[0106] G grade cement (100 parts), silica fume (35 parts), fluid loss reducer 1 (5 parts), retarder (1.5 parts) of comparative example 2, tap water (53 parts).

[0107] Table 1 Comparative experimental results

[0108]

[0109] Note: 160℃×80min×80MPa in Table 1 is the experimental condition for evaluating the high temperature and high pressure thickening performance after the retarder is added to the cement slurry.

[0110] 80℃×21MPa×72h in Table 1 is the curing condition of cement.

[0111] It can be seen from the results of Test Examples 2, 7 and 8 that the effect of cement slurry retarders prepared from single organic materials or inorganic materials is not as good as the effect of cement slurry retarders prepared from organic-inorganic hybrid materials formed by organic materials and inorganic materials of the present invention. It can be seen that the organic-inorganic hybrid materials formed by organic materials and inorganic materials of the present invention have a synergistic effect, and the retarders prepared by them are added to the cement slurry system for high temperature and high pressure thickening, and the thickening time is longer and the compressive strength is greater.

[0112] Test Example 9

[0113] The cement slurry retarder prepared in Example 1 was added to the cement slurry in an amount of 1% to 3% of the mass of cement ash, and the high temperature and high pressure thickening performance was evaluated under the conditions of 160°C×80min×80MPa. The specific results are shown in Table 2.

[0114] Table 2

[0115] Serial number Retarder dosage % Experimental conditions Thickening time / min 1 1.0 160℃×80min×80MPa 121 2 1.2 160℃×80min×80MPa 246 3 1.5 160℃×80min×80MPa 306 4 1.8 160℃×80min×80MPa 367 5 2.0 160℃×80min×80MPa 435

[0116] It can be seen from the results in Table 2 that the cement retarder of the present invention has good temperature resistance, can meet the experimental requirements at 160° C., and has a good thickening linear relationship.

[0117] In summary, the present invention provides a novel oil well cement retarder, which is a solid retarder after inorganic and organic hybridization, has good stability, can adapt to the requirements of different external environmental changes, has small addition amount and high efficiency, has good temperature resistance, can be used under 160°C conditions, and within 72 hours, the curing strength develops rapidly under 80°C conditions, which can effectively solve the problem of cementing construction with large temperature difference.

[0118] The present invention has been described in detail above in conjunction with specific implementations and exemplary examples, but these descriptions cannot be understood as limiting the present invention. Those skilled in the art understand that, without departing from the spirit and scope of the present invention, a variety of equivalent substitutions, modifications or improvements may be made to the technical solution of the present invention and its implementation methods, all of which fall within the scope of the present invention. The scope of protection of the present invention shall be subject to the attached claims.

[0119] All publications, patent applications, patents and other references mentioned in this specification are incorporated herein by reference. Unless otherwise defined, all technical and scientific terms used in this specification have the meanings conventionally understood by those skilled in the art. In the event of a conflict, the definition in this specification shall prevail.

[0120] When this specification uses the prefix "well-known to those skilled in the art", "prior art" or similar terms to introduce materials, substances, methods, steps, devices or components, etc., the objects introduced by the prefix cover those commonly used in the art when this application is filed, but also include those that are not commonly used at present but will become recognized in the art as being suitable for similar purposes.

[0121] In the context of the present specification, any matters or items not mentioned are directly applicable to those known in the art without any changes except those explicitly stated.

Claims

1. A cement slurry retarder, characterized in that: The cement slurry retarder is an organic-inorganic hybrid material formed by an organic material and an inorganic material; the organic material is selected from substances having a carboxylate and / or hydroxyl structure; and the inorganic material is selected from compounds having a layered structure.

2. The cement slurry retarder according to claim 1, characterized in that: The organic material includes a stabilizer and a coagulant; Preferably, the stabilizer is selected from at least one of yellow dextrin and white dextrin; and / or, The coagulant is selected from at least one of tartaric acid, sodium glucoheptonate and sodium gluconate; More preferably, the coagulant is selected from a mixture of tartaric acid, sodium glucoheptonate and sodium gluconate.

3. The cement slurry retarder according to claim 1, characterized in that: The organic material is loaded into the layered structure of the inorganic material; preferably, the organic material is intercalated into the layered structure of the inorganic material.

4. The cement slurry retarder according to any one of claims 1 to 3, characterized in that: The mass ratio of the organic material to the inorganic material is 0.4 to 0.7; Preferably, the mass ratio of the coagulant to the stabilizer in the organic material is 0.7 to 1.

3.

5. The cement slurry retarder according to claim 1, characterized in that: The inorganic material is selected from hydroxides having a layered structure, Preferably, the inorganic material is selected from hydrotalcite; Further preferably, the inorganic material is selected from at least one of calcium aluminum hydrotalcite and calcium magnesium hydrotalcite; More preferably, the hardness of the hydrotalcite is 3.5-4 and the density is 2.7-2.8 g / cm 3 .

6. The cement slurry retarder according to claim 2, characterized in that: In parts by weight, the cement slurry retarder comprises: The stabilizer is 6 to 10 parts by weight; Tartaric acid is 3 to 5 parts by weight; Sodium glucoheptonate is 1 to 3 parts by weight; Sodium gluconate is 0.5 to 3 parts by weight; The inorganic material is 25 to 30 parts by weight.

7. The cement slurry retarder according to claim 6, characterized in that: In parts by weight, the cement slurry retarder comprises: 6 to 8 parts by weight of a stabilizer; and / or, 3 to 5 parts by weight of tartaric acid; and / or, Sodium glucoheptonate is 1 to 2 parts by weight; and / or, Sodium gluconate is 0.5 to 1 parts by weight; and / or, The inorganic material is 27 to 29 parts by weight.

8. A method for preparing a cement slurry retarder, characterized in that: The following steps are involved: Dry-mixing and loading the organic material and the inorganic material to obtain the cement slurry retarder; It is preferably used for the preparation of the cement slurry retarder according to any one of claims 1 to 7.

9. The method for preparing a cement slurry retarder according to claim 8, characterized in that: When the dry mix is ​​loaded, a planetary ball mill is used for grinding; Preferably, the grinding speed is 60 to 180 r / min; and / or, Each grinding time is 20 to 40 minutes, and the number of grinding times is 4 times; and / or, The grinding balls are made of 3-5 mm zirconium oxide; and / or, The mass ratio of the grinding balls to the ground sample is controlled at 8 to 10; and / or, The particle size of each material in the organic material is between 180 and 200 meshes.

10. Use of the cement slurry retarder according to any one of claims 1 to 7 or the cement slurry retarder prepared by the method according to any one of claims 8 to 9 in the oil field, preferably in oil production cementing construction.

11. A cement slurry, characterized in that: The cement slurry comprises the cement slurry retarder according to any one of claims 1 to 7 or the cement slurry retarder prepared by the method according to any one of claims 8 to 9 and cement ash; Preferably, in the cement slurry, the mass ratio of the added cement slurry retarder to the added cement ash is 1% to 3%:1.

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