High-temperature triggering type CO2 gas channeling resisting blocking agent and preparation method thereof

Abstract

The invention provides a high-temperature triggering type blocking agent for resisting CO2 gas channeling and a preparation method thereof. The high-temperature triggering type blocking agent for resisting CO2 gas channeling is prepared from the following components in parts by weight: 100 to 120 parts of cement, 100 to 120 parts of epoxy resin, 3 to 8 parts of aluminum dihydrogen phosphate, 25 to 35 parts of curing agent and 15 to 20 parts of diluent. Aluminum dihydrogen phosphate reacts with aluminum oxide in cement to generate aluminum phosphate with a spatial net structure, the aluminum phosphate participates in cement curing to promote cement curing, hydroxyl in phosphoric acid reacts with epoxy resin, adhesion between cement and epoxy resin is converted into connection of chemical bonds, and the cement curing effect is improved. The cohesiveness, the stability and the strength of the plugging agent are obviously improved. In addition, through mutual cooperation of all the components, the plugging agent further has good construction performance, not only is excellent in compressive strength, but also has the advantages of being small in volume shrinkage, tight in joint, high in corrosion resistance and the like.

Description

Technical Field

[0001] The present invention relates to the field of oil development, and in particular, to a high-temperature triggered CO 2 gas escape plugging agent and a preparation method thereof. Background Art

[0002] CO 2 As an effective method to improve oil recovery, carbon dioxide capture, utilization and storage (CCUS) has been applied to oilfield development practice as early as the 1960s abroad. In recent years, with the development of low-permeability oil reservoirs, the use of water and chemical flooding methods can no longer meet the production requirements, and it is extremely easy to cause damage to the injected fluid. However, during the CO 2 flooding process, due to the slippage effect and viscous fingering effect of gas, gas channeling is likely to occur, and generally there are problems such as large pore channel crossflow and high-permeability layer breakthrough. The early breakthrough of the injected CO 2 will cause most of the reservoirs in the oil reservoir not to be affected, making the CO 2 development difficult to achieve the expected effect. Therefore, before CO 2 flooding, effective channel plugging must be carried out. Therefore, for the formation of relatively wide escape channels due to large fractures and large pore channels in the formation, a CO 2 gas escape plugging agent and a preparation method thereof need to be proposed. At present, the use of cement and gel particles for plugging during water flooding has been widely used, and good on-site effects and experience have been obtained. However, there are few reports on its application effect in the acidic environment of high-temperature CO 2 flooding.

[0003] Patent Application No. 201811171792.3 discloses a cement slurry system and a preparation method thereof, which are made of the following raw materials: G-class oil well cement, high-temperature resistant elastic material, high-temperature resistant fluid loss reducer, high-temperature resistant inorganic channeling prevention emulsion, weighting agent, high-temperature strength stabilizer, dispersant, slurry regulator, retarder and water. This system has good elastic properties in high-temperature and high-pressure environments and can effectively ensure interlayer sealing, but its compressive strength is <35 MPa / 7d, and the compressive strength at 60d is greater than 30 MPa.

[0004] In view of this, the present invention is specifically proposed. Summary of the Invention

[0005] The main object of the present invention is to provide a high-temperature triggered CO 2 gas escape plugging agent and a preparation method thereof to solve the problem of low compressive strength of the existing cement slurry system plugging agent.

[0006] To achieve the above object, according to one aspect of the present invention, a high-temperature triggered CO 2Gas escape plugging agent. By weight, this high-temperature triggered anti-CO 2 The gas escape plugging agent comprises 100 - 120 parts of cement, 100 - 120 parts of epoxy resin, 3 - 8 parts of aluminum dihydrogen phosphate, 25 - 35 parts of curing agent, and 15 - 20 parts of diluent.

[0007] Furthermore, the above-mentioned cement includes at least one of high-alumina cement or portland cement, preferably high-alumina cement.

[0008] Furthermore, the above-mentioned high-alumina cement includes alumina, and the content of the alumina is 50 - 77 wt%, preferably the above-mentioned high-alumina cement is selected from at least one of CA50 - A600, CA60 - A600, and CA70 - A600.

[0009] Furthermore, the above-mentioned epoxy resin includes at least one of waterborne epoxy resin, adhesive-curing epoxy resin, and solvent-based epoxy resin.

[0010] Furthermore, the epoxy resin is selected from at least one of E-44, E-51, and E-52; and / or, the epoxy resin is selected from at least one of EP-301, EP-404, and EP-512; and / or, the epoxy resin is selected from at least one of BE-234X-85, BE-501L-65, and BE-501M-70.

[0011] Furthermore, the above-mentioned curing agent is an amine substance, including at least one of ethylenediamine, polyamide, and m-phenylenediamine.

[0012] Furthermore, the above-mentioned diluent is an organic solvent, including at least one of ethanol, acetone, and benzene.

[0013] According to another aspect of the present invention, there is provided a preparation method of the aforementioned high-temperature triggered anti-CO 2 gas escape plugging agent. The preparation method includes: mixing the above-mentioned cement, the above-mentioned epoxy resin, the above-mentioned aluminum dihydrogen phosphate, the above-mentioned curing agent, and the above-mentioned diluent evenly to obtain the above-mentioned high-temperature triggered anti-CO 2 gas escape plugging agent.

[0014] Furthermore, first mix the above-mentioned diluent and the above-mentioned epoxy resin for the first time, then add the above-mentioned curing agent for the second time, and then add the above-mentioned cement and the above-mentioned aluminum dihydrogen phosphate for the third time to obtain the above-mentioned high-temperature triggered anti-CO 2 gas escape plugging agent.

[0015] Applying the technical solution of the present invention, the high-temperature triggered anti-CO provided by the present invention 2The gas channeling plugging agent reacts with alumina in cement through aluminum dihydrogen phosphate to generate spatial network-structured aluminum phosphate, which participates in the cement curing process and promotes cement curing. The hydroxyl groups in phosphoric acid react with epoxy resin to convert the adhesion between cement and epoxy resin into a chemical bond connection, significantly improving the bonding property, stability, and strength of the plugging agent. In addition, through the mutual coordination of its components, the plugging agent of the present invention also has good construction performance, not only excellent compressive strength, but also characteristics such as small volume shrinkage, tight joints, and strong corrosion resistance, having broad application prospects in the field of reservoir development. Detailed implementation mode

[0016] It should be noted that, without conflict, the embodiments in this application and the features in the embodiments can be combined with each other. The present invention will be described in detail below with reference to the embodiments.

[0017] As analyzed in the background art of this application, there are problems in the plugging agent of the cement slurry system in the current technology, such as low compressive strength, poor corrosion resistance, and serious strength decline. To solve this problem, the present invention provides a high-temperature triggered anti-CO 2 gas channeling plugging agent and its preparation method.

[0018] In a typical implementation mode of this application, a high-temperature triggered anti-CO 2 gas channeling plugging agent is provided. In terms of parts by weight, this high-temperature triggered anti-CO 2 gas channeling plugging agent includes 100 - 120 parts of cement, 100 - 120 parts of epoxy resin, 3 - 8 parts of aluminum dihydrogen phosphate, 25 - 35 parts of curing agent, and 15 - 20 parts of diluent.

[0019] The high-temperature triggered anti-CO 2 gas channeling plugging agent provided in this application forms aluminum phosphate through the reaction of aluminum dihydrogen phosphate with alumina in cement. Using the phosphoric acid structure, the physical mixture between cement and epoxy resin is transformed into a chemical bond combination, not only making the channel plugging system have higher strength and better durability, but also having good compressive resistance and acid resistance.

[0020] In addition, the high-temperature triggered anti-CO 2 gas channeling plugging agent provided in this application, through the mutual coordination of cement, epoxy resin, aluminum dihydrogen phosphate, curing agent, and diluent, has low viscosity and high fluidity at normal temperature, providing good pumpability for the plugging agent. At the same time, using the curing agent, a chemical reaction occurs with epoxy resin to form a networked three-dimensional polymer. After mixing with cement, a plugging system with higher strength, better bonding property, and acid resistance is formed.

[0021] Typical but non-limiting, in the high-temperature triggered anti-CO 2In the gas escape plugging agent, the dosage of cement is 100 parts, 102 parts, 105 parts, 108 parts, 110 parts, 112 parts, 115 parts, 118 parts, 120 parts or a range value composed of any two numerical values; the dosage of epoxy resin is 100 parts, 102 parts, 105 parts, 108 parts, 110 parts, 112 parts, 115 parts, 118 parts, 120 parts or a range value composed of any two numerical values; the dosage of aluminum dihydrogen phosphate is 3 parts, 3.5 parts, 4 parts, 4.5 parts, 5 parts, 6 parts, 7 parts, 8 parts or a range value composed of any two numerical values; the dosage of curing agent is 25 parts, 28 parts, 30 parts, 32 parts, 35 parts or a range value composed of any two numerical values; the dosage of diluent is 15 parts, 16 parts, 17 parts, 18 parts, 19 parts, 20 parts or a range value composed of any two numerical values.

[0022] The cement is the cement commonly used in the art, including but not limited to any one or a mixture of high-alumina cement and portland cement. In order to increase the chemical corrosion resistance and high-temperature resistance of the cement, high-alumina cement is preferably used. The high-alumina cement contains 50-77 wt% of alumina. By controlling the content of alumina, the setting reaction of the cement can be improved, and at the same time, the friction between cement particles can be reduced, and the fluidity and plasticity of the cement can be improved.

[0023] Typically but not restrictively, in the above high-alumina cement, the mass content of the above alumina is 50%, 52%, 55%, 58%, 60%, 62%, 65%, 68%, 70%, 72%, 75%, 77% or a range value composed of any two numerical values.

[0024] The above high-alumina cement includes but not limited to the following models: CA50-A600 (alumina content is 50-60 wt%), CA60-A600 (alumina content is 60-68 wt%), CA70-A600 (alumina content is 68-77 wt%). One or more of the above models of cement can be obtained through commercial channels, such as Zhengzhou Dengfeng Melting Material Co., Ltd.

[0025] In this application, using the above high-alumina cement as a raw material is more conducive to the reaction between alumina in the cement and aluminum dihydrogen phosphate, so that the physical mixing between the cement and the epoxy resin is transformed into a chemical bond combination, thereby further improving the strength and chemical corrosion resistance of the plugging system formed by the plugging agent.

[0026] In this application, the epoxy resin is the main resin for forming a crosslinked system. When the epoxy resin is cured, it generally does not release small molecule compounds and has a small shrinkage rate. Therefore, the molding process is better, and at the same time, a crosslinked system with fewer voids and higher strength can be obtained.

[0027] The specific type of epoxy resin used in this application is not limited, and any epoxy resin that can form a plugging system is acceptable, including but not limited to any one or several of waterborne epoxy resin, glue-curing epoxy resin, and solvent-based epoxy resin to form a mixed epoxy resin.

[0028] In some specific embodiments, the above epoxy resin includes a mixed resin of any one or several of E-44, E-51, and E-52, and E-44, E-51, and E-52 can be obtained commercially, such as Nantong Xingchen Synthetic Materials Co., Ltd.

[0029] In some other specific embodiments, the above epoxy resin includes a mixed resin of any one or several of EP-301, EP-404, and EP-512, and EP-301, EP-404, and EP-512 can be obtained commercially, such as Dongguan Fuze Chemical Co., Ltd.

[0030] In some other specific embodiments, the above epoxy resin includes a mixed resin of any one or several of BE-234X-85, BE-501L-65, and BE-501M-70, and BE-234X-85, BE-501L-65, and BE-501M-70 can be obtained commercially, such as Xiamen Aikema Chemical Co., Ltd.

[0031] In order to make the formed slurry have a closer connection, a more regular structure, and better compressive strength than traditional gels, the high-temperature triggered anti-CO 2 gas escape plugging agent is added with aluminum dihydrogen phosphate, and aluminum phosphate is generated by the reaction of aluminum dihydrogen phosphate with alumina in cement. Using the phosphate structure, the physical mixing between cement and epoxy resin is transformed into a chemical bond combination, so that the prepared high-temperature triggered anti-CO 2 gas escape plugging agent has higher compressive strength and better durability with the increase of temperature, and at the same time has good acid resistance.

[0032] In order to form a material with higher strength, better adhesion, and acid resistance, the high-temperature triggered anti-CO 2 gas escape plugging agent is added with a curing agent. Since this application uses epoxy resin as the main resin of the cross-linking agent, amines are preferably used as the curing agent. Different amine substances have different activities, and the curing temperature of epoxy resin is different. Ethylenediamine is preferably used. Ethylenediamine has a large activity and can cross-link and cure epoxy resin at room temperature.

[0033] During the curing process, the curing effect of amines on epoxy resin is to open the C-O bond of the epoxy group by the active hydrogen on the nitrogen atom of primary amine and / or secondary amine, so that the epoxy resin crosslinks and cures. If the curing agent is too little, the epoxy resin cannot cure after being left for a long time. If it is too much, the epoxy resin cures too quickly and becomes a non-sticky solid without adhesive force. Therefore, in the plugging agent provided in this application, the mass ratio of the curing agent to the epoxy resin is 25-35:100-120.

[0034] To improve the pumpability of the plugging agent and make the plugging agent have good injection performance, a diluent is added to the high-temperature triggered anti-CO 2 gas escape plugging agent. Preferably, an organic solvent is used as the diluent. After adding the diluent, the viscosity of the plugging system is reduced and the fluidity is increased, so that it has good injection performance. At the same time, the organic solvent is cheap and easily available, reducing the cost.

[0035] In this application, there is no restriction on the specific type of the diluent. Any diluent commonly used in the field of plugging agents can be used, including but not limited to any one or a mixture of ethanol, acetone, and benzene. Especially when ethanol is selected as the diluent, it can reduce the cost while ensuring safety and environmental protection.

[0036] A high-temperature triggered anti-CO 2 gas escape plugging agent provided by this application adds a diluent to increase the fluidity of the epoxy resin, adds a curing agent to cause chemical crosslinking of the epoxy resin, and uses aluminum phosphate with a phosphate structure formed by aluminum oxide and aluminum dihydrogen phosphate in cement to transform the physical mixture of epoxy resin and cement into chemical crosslinking, giving play to the synergistic effect between each component, improving the compressive strength, corrosion resistance and durability of the plugging agent, while retarding setting at normal temperature and accelerating setting at high temperature, and the forming process is controllable. The raw materials in the plugging agent are easily available and have good compatibility.

[0037] In another typical embodiment of this application, a preparation method of a high-temperature triggered anti-CO 2 gas escape plugging agent is provided. The preparation method includes: mixing cement, epoxy resin, aluminum dihydrogen phosphate, curing agent and diluent evenly to obtain a high-temperature triggered anti-CO 2 gas escape plugging agent.

[0038] The preparation method of the high-temperature triggered anti-CO 2 gas escape plugging agent provided by this application has a simple process and is easy to operate, and is suitable for application in oilfield development practice.

[0039] In some embodiments, the high-temperature triggered anti-CO 2The preparation method of the gas leakage plugging agent is carried out according to the following steps: firstly, the diluent and the epoxy resin are mixed for the first time to obtain a first mixture, the fluidity of the epoxy resin is increased, and the viscosity thereof is reduced; then, a curing agent is added to the first mixture for a second mixing to obtain a second mixture, so that the epoxy resin in the first mixture is chemically cross-linked to form a network-like three-dimensional polymer; then, cement, aluminum dihydrogen phosphate and kashun are added to the second mixture for a third mixing to obtain the high temperature triggered anti-CO 2 Gas leakage plugging agent. During the third mixing process, the aluminum phosphate generated by mixing cement and aluminum dihydrogen phosphate converts the physical adhesion between cement and epoxy resin into chemical crosslinking, making the obtained high temperature triggered anti-CO 2 The compressive strength of the gas leakage plugging agent is increased.

[0040] During the preparation of the first mixture, 15 to 20 parts of ethanol and 100 to 120 parts of epoxy resin are mixed evenly.

[0041] During the preparation of the second mixture, 25 to 35 parts of ethylenediamine are added to the first mixture.

[0042] During the preparation of the third mixture, 100 to 120 parts of cement and 3 to 8 parts of aluminum dihydrogen phosphate are added to the second mixture.

[0043] This application provides a high temperature triggered anti-CO 2 After the gas leakage plugging agent is injected into the reservoir, it forms a stable three-dimensional network structure through cementation as the temperature rises, making the plugging agent have good chemical stability and can achieve long-term plugging. 2 The gas leakage plugging agent has slow coagulation at room temperature and accelerated coagulation at high temperature, and the gelling process is controllable, thus having good construction performance. At the same time, it significantly improves the compressive strength of the cross-linking system, making it have the characteristics of small volume shrinkage, tight joints, and strong corrosion resistance.

[0044] The following will further illustrate the beneficial effects of the present application in combination with the embodiments and comparative examples.

[0045] Example 1

[0046] This embodiment provides a high temperature triggered anti-CO 2 The gas leakage plugging agent includes, by weight, 15 parts of ethanol, 100 parts of epoxy resin, 25 parts of ethylenediamine, 100 parts of cement and 3 parts of aluminum dihydrogen phosphate; wherein the cement is CA50-A600 and the epoxy resin is EP-301.

[0047] ​The plugging agent is prepared according to the following steps: Add 15 parts of ethanol to 100 parts of epoxy resin. After uniform mixing, slowly add 25 parts of ethylenediamine, and finally add 100 parts of cement and 3 parts of aluminum dihydrogen phosphate to obtain a high-temperature triggered anti-CO 2 gas escape plugging agent.

[0048] Example 2

[0049] This example provides a high-temperature triggered anti-CO 2 gas escape plugging agent. By weight, the plugging agent includes 17 parts of ethanol, 100 parts of epoxy resin, 30 parts of ethylenediamine, 100 parts of cement and 5 parts of aluminum dihydrogen phosphate; among them, the cement is CA50 - A600, and the epoxy resin is EP - 301.

[0050] The plugging agent is prepared according to the following steps: Add 17 parts of ethanol to 100 parts of epoxy resin. After uniform mixing, slowly add 30 parts of ethylenediamine, and finally add 100 parts of cement and 5 parts of aluminum dihydrogen phosphate to obtain a high-temperature triggered anti-CO 2 gas escape plugging agent.

[0051] Example 3

[0052] This example provides a high-temperature triggered anti-CO 2 gas escape plugging agent. By weight, the plugging agent includes 20 parts of ethanol, 100 parts of epoxy resin, 35 parts of ethylenediamine, 100 parts of cement and 5 parts of aluminum dihydrogen phosphate; among them, the cement is CA50 - A600, and the epoxy resin is EP - 301.

[0053] The plugging agent is prepared according to the following steps: Add 20 parts of ethanol to 100 parts of epoxy resin. After uniform mixing, slowly add 35 parts of ethylenediamine, and finally add 100 parts of cement and 5 parts of aluminum dihydrogen phosphate to obtain a high-temperature triggered anti-CO 2 gas escape plugging agent.

[0054] Example 4

[0055] This example provides a high-temperature triggered anti-CO 2 gas escape plugging agent. By weight, the plugging agent includes 15 parts of ethanol, 100 parts of epoxy resin, 25 parts of ethylenediamine, 100 parts of cement and 8 parts of aluminum dihydrogen phosphate; among them, the cement is CA50 - A600, and the epoxy resin is EP - 301.

[0056] The plugging agent is prepared according to the following steps: Add 15 parts of ethanol to 100 parts of epoxy resin. After uniform mixing, slowly add 25 parts of ethylenediamine, and finally add 100 parts of cement and 8 parts of aluminum dihydrogen phosphate to obtain a high-temperature triggered anti-CO 2Gas escape plugging agent.

[0057] Example 5

[0058] This example provides a high-temperature triggered anti-CO 2 gas escape plugging agent. By weight, the plugging agent includes 15 parts of ethanol, 100 parts of epoxy resin, 25 parts of ethylenediamine, 120 parts of cement, and 3 parts of aluminum dihydrogen phosphate; among them, the cement is CA50-A600, and the epoxy resin is EP-301.

[0059] The plugging agent is prepared according to the following steps: Take 15 parts of ethanol and add it to 100 parts of epoxy resin. After uniform mixing, slowly add 25 parts of ethylenediamine, and finally add 120 parts of cement and 3 parts of aluminum dihydrogen phosphate to obtain a high-temperature triggered anti-CO 2 gas escape plugging agent.

[0060] Example 6

[0061] This example provides a high-temperature triggered anti-CO 2 gas escape plugging agent. By weight, the plugging agent includes 15 parts of ethanol, 120 parts of epoxy resin, 25 parts of ethylenediamine, 100 parts of cement, and 3 parts of aluminum dihydrogen phosphate; among them, the cement is CA50-A600, and the epoxy resin is EP-301.

[0062] The plugging agent is prepared according to the following steps: Take 15 parts of ethanol and add it to 120 parts of epoxy resin. After uniform mixing, slowly add 25 parts of ethylenediamine, and finally add 100 parts of cement and 3 parts of aluminum dihydrogen phosphate to obtain a high-temperature triggered anti-CO 2 gas escape plugging agent.

[0063] Example 7

[0064] The difference between this example and Example 4 is that E-44 epoxy resin is used to replace EP-301 epoxy resin in Example 4.

[0065] Example 8

[0066] The difference between this example and Example 4 is that BE-234X-85 epoxy resin is used to replace EP-301 epoxy resin in Example 4.

[0067] Example 9

[0068] The difference between this example and Example 4 is that the cement used is CA60-A600.

[0069] Example 10

[0070] The difference between this example and Example 4 is that the cement used is CA70-A600.

[0071] Example 11

[0072] The difference between this example and Example 4 is that the cement used is P052.5 grade portland cement to replace the cement in Example 4.

[0073] Comparative Example 1

[0074] The difference between this comparative example and Example 4 is that no aluminum dihydrogen phosphate is added.

[0075] Comparative Example 2

[0076] The difference between this comparative example and Example 4 is that polyethylene resin is used to replace epoxy resin.

[0077] Comparative Example 3

[0078] The difference between this comparative example and Example 4 is that the dosage of aluminum dihydrogen phosphate is 2 parts by weight.

[0079] Comparative Example 4

[0080] The difference between this comparative example and Example 4 is that the dosage of aluminum dihydrogen phosphate is 10 parts by weight.

[0081] Comparative Example 5

[0082] The difference between this comparative example and Example 4 is that the dosage of CA50 - A600 cement is 75 parts by weight and the dosage of EP - 301 epoxy resin is 125 parts by weight.

[0083] Comparative Example 6

[0084] The difference between this comparative example and Example 4 is that the dosage of CA50 - A600 cement is 135 parts by weight and the dosage of EP - 301 epoxy resin is 65 parts by weight.

[0085] Test Example

[0086] In order to determine the various properties of this high - temperature triggered anti - CO 2 gas escape plugging agent, the plugging property, compressive strength, bond strength, heat resistance, acid resistance and anti - seepage strength of the high - temperature triggered anti - CO 2 gas escape plugging agent provided in the examples and comparative examples were tested, and the results are shown in Table 1.

[0087] 1. Plugging Performance Test

[0088] An indoor sand - filled pipe simulation experiment was adopted. The diameter of the single - pipe sand - filled pipe was 3.0 cm and the length was 40.0 cm. Quartz sand with different particle sizes was used to press the sand - filled pipe. First, the CO 2Driving permeability, then injecting the prepared channel plugging agent solution into the sand-filled tube, keeping it at a constant temperature of 80°C for 48 hours, and then using CO 2 To displace and measure the permeability of the sand-filled tube.

[0089] 2. Compressive strength test

[0090] Conduct the test in accordance with the compressive strength test standard specifications in JGJ / T70-2009 "Standard for Test Methods of Basic Properties of Building Mortars". Pour the prepared channel plugging agent slurry into a weighing densitometer to measure the density, and then pour the prepared channel plugging agent slurry into a mold to make a 25×25mm cylindrical module. Cure it in a water bath at 80°C, 120°C, and 180°C for 10 days and then demold it, and test the compressive strength on a universal material testing device.

[0091] 3. Bonding strength test

[0092] Conduct the interfacial shear strength experiment in accordance with GB / T31541-2015 "Test Methods for Tensile and Shear Bonding Strength of Fine Ceramics - Crossed Cross Method". The loading speed is 0.5mm / min, and apply a compressive load uniformly until the bonding surface (with an area of 4mm×4mm) is damaged, and record the bonding strength at the time of interfacial fracture.

[0093] 4. Heat resistance test

[0094] Establish the relationship between the plugging rate and the experimental time (10d, 20d, 30d) to evaluate the heat resistance performance of the plugging agent.

[0095] 5. Acid resistance test

[0096] Soak the dried plugging agent in an acid solution with pH = 3 and seal it. After placing it in a water bath at 180°C for 24 hours, evaluate its acid resistance.

[0097] 6. Impermeability test

[0098] Conduct the test in accordance with the standard specifications in JGJ / T70-2009 "Standard for Test Methods of Basic Properties of Building Mortars". After the test piece is formed and demolded, place it in the curing room for 28 days. After taking it out and waiting for the surface to dry, load it into the mortar permeameter for impermeability test.

[0099] Table 1

[0100]

[0101]

[0102] From the above description, it can be seen that the above embodiments of the present invention achieve the following technical effects:

[0103] The present invention provides a high-temperature triggered anti-CO 2The gas channeling plugging agent adds a diluent to increase the fluidity of epoxy resin, adds a curing agent to cause chemical cross-linking of epoxy resin, and utilizes aluminum phosphate with a phosphoric acid structure formed by aluminum oxide and aluminum dihydrogen phosphate in cement to transform the physical mixture of epoxy resin and cement into chemical cross-linking, giving play to the synergistic effect among the components, improving the compressive strength, corrosion resistance and durability of the plugging agent. At the same time, it has retarding setting at normal temperature and accelerating setting at high temperature, with a controllable forming process and good construction performance, and has broad application prospects in the field of reservoir development.

[0104] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, various changes and modifications can be made to the present invention. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A high temperature triggered anti-CO2 gas leakage plugging agent, characterized in that: In parts by weight, the high-temperature triggered anti-CO2 gas leakage plugging agent includes 100 to 120 parts of cement, 100 to 120 parts of epoxy resin, 3 to 8 parts of aluminum dihydrogen phosphate, 25 to 35 parts of curing agent, and 15 to 20 parts of diluent.

2. The high temperature triggered anti-CO2 gas leakage plugging agent according to claim 1, characterized in that: The cement comprises at least one of high alumina cement or silicate cement, preferably high alumina cement.

3. The high temperature triggered anti-CO2 gas leakage plugging agent according to claim 2, characterized in that: The high alumina cement comprises alumina, and the content of the alumina is 50-77 wt %.

4. The high temperature triggered anti-CO2 gas leakage plugging agent according to claim 3 is characterized in that: The high alumina cement is selected from at least one of CA50-A600, CA60-A600, and CA70-A600.

5. The high temperature triggered anti-CO2 gas leakage plugging agent according to claim 1, characterized in that: The epoxy resin includes at least one of a water-based epoxy resin, a glue-curing epoxy resin, and a solvent-based epoxy resin.

6. The high temperature triggered anti-CO2 gas leakage plugging agent according to claim 5, characterized in that: The epoxy resin is selected from at least one of E-44, E-51, and E-52; And / or, the epoxy resin is selected from at least one of EP-301, EP-404, and EP-512; And / or, the epoxy resin is selected from at least one of BE-234X-85, BE-501L-65, and BE-501M-70.

7. The high temperature triggered anti-CO2 gas leakage plugging agent according to claim 1, characterized in that: The curing agent is an amine substance, and the amine substance includes at least one of ethylenediamine, polyamide, and metaphenylenediamine.

8. The high temperature triggered anti-CO2 gas leakage plugging agent according to claim 1, characterized in that: The diluent is an organic solvent, and the organic solvent includes at least one of ethanol, acetone, and benzene.

9. A method for preparing the high temperature triggered anti-CO2 gas leakage plugging agent according to any one of claims 1 to 8, characterized in that: The preparation method comprises: uniformly mixing the cement, the epoxy resin, the aluminum dihydrogen phosphate, the curing agent and the diluent to obtain the high-temperature triggered anti-CO2 gas leakage plugging agent.

10. The preparation method according to claim 9, characterized in that: The diluent and the epoxy resin are first mixed for the first time, and then the curing agent is added for the second mixing, and then the cement and the aluminum dihydrogen phosphate are added for the third mixing to obtain the high-temperature triggered anti-CO2 gas leakage plugging agent.

Images