Foam sand consolidant, its preparation method and application

Abstract

The present application provides a kind of foam sand stabilizer and its preparation method and application, the foam sand stabilizer includes the following components according to weight parts: epoxy resin 100 weight parts, curing agent 25-35 weight parts, emulsifier 5-6 weight parts, foaming agent 1-3 weight parts and foam stabilizer 0.75-4 weight parts.The foam sand stabilizer realizes the salt resistance and high efficient foaming performance of foam sand stabilizer by the design of preparation material and formula, under the simulated salt cave gas storage field application working condition (saturated brine concentration 25%, density 1.22g / cm 3 , temperature 50℃), using the foam sand stabilizer provided by the present application, foaming effect is good, the solid phase particle cementation performance is good, after the adsorption and sedimentation of surrounding particles such as desalination pipe column is cemented and solidified, the sand prevention barrier formed has good permeability and good sand prevention effect, when 1000ml of brine is discharged, the cumulative sand discharge is 0.45g, and the sand discharge rate is only about 0.4%.

Description

Technical Field

[0001] This invention belongs to the field of oil and gas storage technology, specifically relating to a foamed sand-fixing agent, its preparation method, and its application. Background Technology

[0002] Underground salt cavern storage facilities possess unique advantages such as large storage capacity, high storage pressure, high utilization rate, and good economic efficiency. In recent years, they have been widely used in the storage of energy sources such as natural gas, oil, compressed air, hydrogen, and helium, and the scale of application has been increasing year by year. Foreign salt cavern gas storage facilities are generally built in huge salt domes with high salt content, few interlayers, and low insoluble content. Therefore, the insoluble accumulation after the cavity is dissolved in foreign salt cavern gas storage facilities is relatively small, resulting in less storage capacity loss. However, the geological resources for the construction of domestic salt cavern gas storage facilities are mostly layered salt layers (lacustrine sediments), with interlayers of varying proportions (10%-50%). The lithology is mainly mudstone, with some containing anhydrite and glaucophane. The insoluble content in both the salt layers and interlayers is high, reaching as high as 40% in salt layers and over 90% in interlayers. After the cavity is dissolved, a thick layer of accumulated insoluble material remains at the bottom of the cavity, and this accumulation of insoluble material and internal brine occupies a large amount of storage capacity. Statistics show that in areas under construction or planned for construction in China, such as Jintan, Chuzhou, Huai'an, and Pingdingshan, after the creation of salt cavern gas storage wells using the water-soluble method, the volume of insoluble sediment accumulation inside the salt cavern typically accounts for 1 / 3 to 2 / 3 of the total cavity volume, resulting in nearly half of the cavity volume not being effectively utilized. To address this, companies such as CNPC, National Pipeline Network, and Jintan Salt Industry have conducted research and experiments on utilizing the void space in salt cavern sediment and expanding the gas storage space within the cavity.

[0003] The sediment at the bottom of the salt cavern is mainly formed by the fragmentation, expansion, sedimentation, and accumulation of salt rock and water-insoluble interlayers during the water-soluble cavern formation process. The sediment particles vary in size and shape, with an internal porosity as high as 40%-50%, filled with saturated brine and fine sediment particles. The brine density is 1.22-1.3 g / cm³. 3The concentration is around 27%, typically between 40℃ and 60℃. During exploratory experiments on gas injection and brine drainage expansion in the voids of salt cavern bottom sediment, effectively preventing sediment particles from entering and clogging the drainage tubing is a critical challenge. Lowering the drainage tubing into the sediment at the bottom of the salt cavern and using a foam-based sand-fixing agent to bind and solidify the sand around the tubing, forming a highly permeable, sand-controlling artificial wellbore, is considered a feasible process. Existing foam-based sand-fixing agents are mostly used in oil and water wells. By forming a solidified layer around the production tubing or in near-wellbore reservoir fractures and binding it together, they control the amount of sand produced from the reservoir, demonstrating good sand-fixing and sand-controlling effects. However, the sediment at the bottom of salt cavern gas storage tanks is mainly formed by the settling and accumulation of water-insoluble matter from the salt layer and interlayers after fracturing and expansion. It is loosely packed, with low compaction and low mechanical strength, and a porosity as high as approximately 45%. The interior is filled with brine and small particles of residue. During the secondary brine drainage and expansion process in the sediment's void space, these residue particles easily clog the drainage pipes as the brine flows. Currently, there is no relevant research or report abroad regarding the utilization of the void space in the salt cavern sediment, anti-clogging technology measures for the drainage and expansion pipes within the sediment, and the development of reagents. Domestic research is still in the theoretical research and technological breakthrough stage. Therefore, it is urgent to develop a low-cost, high-performance salt-resistant foam sintering agent that can be used for brine drainage and expansion of the sediment at the bottom of salt cavern gas storage tanks, taking into account the physical properties of the sediment and the application environment of highly saturated brine. Summary of the Invention

[0004] To address the shortcomings of existing technologies, the present invention aims to provide a foam sand-fixing agent, its preparation method, and its application. Through the screening and compounding of the various components of the foam sand-fixing agent, it achieves both good sand-fixing and sand-prevention effects and high permeability. It can be applied to the expansion of brine drainage in the pore space of salt cavern gas storage tanks, providing a guarantee for the expansion of brine drainage in the pore space of salt cavern gas storage tanks.

[0005] To achieve this objective, the present invention adopts the following technical solution:

[0006] In a first aspect, the present invention provides a foam slag stabilizer, wherein the foam slag stabilizer comprises the following components by weight: 100 parts by weight of epoxy resin, 25-35 parts by weight of curing agent, 5-6 parts by weight of emulsifier, 1-3 parts by weight of foaming agent and 0.75-4 parts by weight of foam stabilizer.

[0007] The foam slag-fixing agent provided by this invention can be applied to the expansion of brine drainage from the bottom of salt cavern gas storage tanks. Addressing the characteristics of high porosity and strong fluidity of residual particles in the brine from the bottom of salt cavern gas storage tanks, and considering the requirements of high temperature and saturated brine environments in field applications, the foam slag-fixing agent formula has been optimized for salt resistance and foaming performance. Through the synergistic effect of each component, it exhibits excellent foaming and bonding properties, as well as good permeability, fully meeting the application requirements for the expansion of brine drainage from the bottom of salt cavern gas storage tanks.

[0008] The curing agent is 25-35 parts by weight, for example, 25 parts by weight, 26 parts by weight, 27 parts by weight, 28 parts by weight, 29 parts by weight, 30 parts by weight, 31 parts by weight, 32 parts by weight, 33 parts by weight, 34 parts by weight or 35 parts by weight, and specific values ​​between the above values. Due to space limitations and for the sake of brevity, the present invention will not exhaustively list the specific values ​​included in the range.

[0009] The emulsifier is 5-6 parts by weight, for example, 5 parts by weight, 5.1 parts by weight, 5.2 parts by weight, 5.3 parts by weight, 5.4 parts by weight, 5.5 parts by weight, 5.6 parts by weight, 5.7 parts by weight, 5.8 parts by weight, 5.9 parts by weight, or 6 parts by weight, as well as specific values ​​between the above-mentioned values. Due to space limitations and for the sake of brevity, the present invention will not exhaustively list the specific values ​​included in the range.

[0010] The foaming agent is 1-3 parts by weight, for example, it can be 1 part by weight, 1.2 parts by weight, 1.5 parts by weight, 1.8 parts by weight, 2 parts by weight, 2.2 parts by weight, 2.5 parts by weight, 2.8 parts by weight or 3 parts by weight, and specific values ​​between the above values. Due to space limitations and for the sake of brevity, the present invention will not exhaustively list the specific values ​​included in the range.

[0011] The foam stabilizer is 0.75-4 parts by weight, for example, it can be 0.75 parts by weight, 1 part by weight, 1.2 parts by weight, 1.5 parts by weight, 1.8 parts by weight, 2 parts by weight, 2.5 parts by weight, 2.8 parts by weight, 3 parts by weight, 3.5 parts by weight, 3.8 parts by weight or 4 parts by weight, and specific values ​​between the above values. Due to space limitations and for the sake of brevity, the present invention will not exhaustively list the specific values ​​included in the range.

[0012] The following are preferred technical solutions of the present invention, but are not intended to limit the technical solutions provided by the present invention. The purpose and beneficial effects of the present invention can be better achieved and realized through the following preferred technical solutions.

[0013] As a preferred technical solution, the epoxy resin includes epoxy resin E51.

[0014] Preferably, the curing agent includes acid anhydrides and / or amines.

[0015] Preferably, the anhydride includes 4-methyl-1,2-cyclohexanediol.

[0016] Preferably, the amines include any one or a combination of at least two of 650 epoxy resin curing agent, 651 epoxy resin curing agent, or H-113 modified aromatic amine epoxy curing agent.

[0017] As a preferred technical solution, the emulsifier includes dodecylphenol polyoxyethylene ether.

[0018] Preferably, the foaming agent comprises any one or a combination of at least two of polysorbate-80, sodium lauryl sulfate, lauramide propyl hydroxysulfonate betaine, or dodecyl dimethylamine acetone, with dodecyl dimethylamine acetone being more preferred.

[0019] As a preferred technical solution, the foam stabilizer includes a combination of polymeric foam stabilizers and particulate foam stabilizers.

[0020] Preferably, the polymeric foam stabilizer includes any one of PEG-2000, PEG-6000, PEG-10000, PVA1788, or hydroxyethyl cellulose.

[0021] Preferably, the polymeric foam stabilizer is 0.5-3 parts by weight, for example, 0.5 parts by weight, 0.8 parts by weight, 1 part by weight, 1.5 parts by weight, 1.8 parts by weight, 2 parts by weight, 2.5 parts by weight, 2.8 parts by weight or 3 parts by weight, and specific values ​​between the above values. Due to space limitations and for the sake of brevity, the present invention will not exhaustively list the specific values ​​included in the range.

[0022] Preferably, the particulate foam stabilizer comprises nano-silica.

[0023] Preferably, the foamed sand-fixing agent also includes an accelerator.

[0024] Preferably, based on 100 parts by weight of the epoxy resin, the mass of the accelerator is ≤13 parts by weight, for example, it can be 0 parts by weight, 1 part by weight, 3 parts by weight, 5 parts by weight, 7 parts by weight, 10 parts by weight, 11 parts by weight, 12 parts by weight or 13 parts by weight, and specific values ​​between the above values. Due to space limitations and for the sake of brevity, the present invention will not exhaustively list the specific values ​​included in the range.

[0025] Preferably, the accelerator comprises any one or a combination of at least two of 2,4,6-tris(dimethylaminomethyl)phenol, methyl dibenzylamine, or organophosphorus / bromine complexes.

[0026] Preferably, the foamed sand-fixing agent further includes a solvent.

[0027] Preferably, the mass ratio of the epoxy resin to the solvent is 1:(0.4-0.8), for example, it can be 1:0.4, 1:0.45, 1:0.5, 1:0.55, 1:0.6, 1:0.65, 1:0.7, 1:0.75 or 1:0.8, etc.

[0028] Preferably, the solvent includes water.

[0029] In a second aspect, the present invention provides a method for preparing a foamed sand-stabilizing agent as described in the first aspect, the method comprising the following steps:

[0030] (1) The epoxy resin is mixed with an emulsifier and then emulsified to obtain an emulsion. A solvent is added to the emulsion to obtain a base liquid.

[0031] (2) The base liquid, curing agent, optional accelerator, foaming agent and foam stabilizer obtained in step (1) are mixed to obtain the foam sand fixing agent.

[0032] Preferably, the emulsification temperature is 70-80℃, for example, it can be 70℃, 71℃, 72℃, 73℃, 74℃, 75℃, 76℃, 77℃, 78℃, 79℃ or 80℃, as well as specific values ​​between the above points. Due to space limitations and for the sake of brevity, the present invention will not exhaustively list the specific values ​​included in the range.

[0033] Preferably, the emulsification time is 5-30 min; for example, it can be 5 min, 7 min, 10 min, 13 min, 15 min, 18 min, 20 min, 23 min, 25 min, 28 min or 30 min, as well as specific values ​​between the above values. Due to space limitations and for the sake of brevity, the present invention will not exhaustively list the specific values ​​included in the range.

[0034] Preferably, the emulsification is carried out under stirring.

[0035] Preferably, the stirring speed is 5000-8000 r / min, for example, it can be 5000 r / min, 5200 r / min, 5500 r / min, 5800 r / min, 6000 r / min, 6200 r / min, 6500 r / min, 6800 r / min, 7000 r / min, 7200 r / min, 7500 r / min, 7800 r / min or 8000 r / min, and specific values ​​between the above values. Due to space limitations and for the sake of brevity, the present invention will not exhaustively list the specific values ​​included in the range.

[0036] Preferably, the viscosity of the base liquid is 0.05-2 Pa·s; for example, it can be 0.05 Pa·s, 0.08 Pa·s, 0.1 Pa·s, 0.12 Pa·s, 0.15 Pa·s, 0.18 Pa·s, or 0.2 Pa·s, as well as specific values ​​between the above values. Due to space limitations and for the sake of brevity, the present invention will not exhaustively list the specific values ​​included in the range.

[0037] Thirdly, the present invention provides an application of a foamed epoxy resin composition in a foamed sand-fixing agent, wherein the foamed epoxy resin composition comprises the following components by weight: 100 parts by weight of epoxy resin, 25-35 parts by weight of curing agent, 5-6 parts by weight of emulsifier, 1-3 parts by weight of foaming agent and 0.75-4 parts by weight of foam stabilizer.

[0038] The present invention also provides an application of the foamed sand-fixing agent as described in the first aspect, wherein the foamed sand-fixing agent is used in the expansion of the brine discharge from the bottom of a salt cavern gas storage tank.

[0039] Preferably, the curing temperature of the foam slurry is 25-50℃, for example, it can be 25℃, 28℃, 30℃, 32℃, 35℃, 38℃, 40℃, 42℃, 45℃, 48℃ or 50℃, as well as specific values ​​between the above points. Due to space limitations and for the sake of brevity, the present invention will not exhaustively list the specific values ​​included in the range.

[0040] Preferably, the curing time of the foamed sand-fixing agent is 2-5 days, for example, it can be 2 days, 2.2 days, 2.5 days, 2.8 days, 3 days, 3.2 days, 3.5 days, 3.8 days, 4 days, 4.2 days, 4.5 days, 4.8 days or 5 days, as well as specific values ​​between the above values. Due to space limitations and for the sake of brevity, the present invention will not exhaustively list the specific values ​​included in the range.

[0041] This invention also provides a supporting process for the application of the foamed sand-fixing agent as described in the first aspect in the brine drainage and expansion of the bottom sediment of a salt cavern gas storage facility: According to the raw material formula and preparation method of the foamed sand-fixing agent, the required foamed sand-fixing agent is prepared on-site. Using equipment such as cement pump trucks / slurry pumps, the prepared foamed sand-fixing agent is injected into the bottom sediment of the salt cavern through a brine drainage pipe column. The agent is squeezed into the sediment surrounding the pipe column through pre-set drainage holes in the sediment section of the pipe column. The process is allowed to solidify for 2 days or more, allowing the foamed sand-fixing agent to fully bond and solidify with the sediment particles around the pipe column. Before applying the foamed sand-fixing agent to the brine drainage and expansion of the bottom sediment of a salt cavern gas storage facility, all ground equipment, pipelines, and instruments must be carefully inspected to ensure that the injection of the foamed sand-fixing agent into the sediment through the brine drainage pipe column is continuous and stable, avoiding incomplete injection, solidification, or blockage of the brine drainage pipe column or ground equipment and pipelines due to equipment / pipeline failure.

[0042] Compared with the prior art, the present invention has the following beneficial effects:

[0043] The foamed sand-fixing agent provided by this invention fully considers the on-site application environment and the physical properties of the sediment at the bottom of the salt cavern gas storage facility. Through the optimization of the preparation materials and formula, the foamed sand-fixing agent achieves both salt resistance and high-efficiency foaming performance. Under simulated on-site application conditions of a salt cavern gas storage facility (saturated brine concentration 25%, density 1.22 g / cm³), it is effective.3 When the temperature is 50℃, the foaming sand-fixing agent provided by this invention has a good foaming effect, good cementing performance for solid particles, and the curing time can be shortened to 2 days. After adsorbing and cementing the sediment particles around the brine discharge column, the sand barrier formed has good permeability and sand-fixing effect. When 1000mL of brine is discharged in simulated working conditions, the cumulative sand discharge is 0.45g, and the sand discharge rate is only about 0.4%. Attached Figure Description

[0044] Figure 1 These are bar charts showing the foaming performance of the foamed sand-fixing agents provided in Examples 1-5 and Comparative Example 1;

[0045] Figure 2 These are bar charts showing the foaming performance of the foamed sand-fixing agents provided in Examples 1 and 6-10;

[0046] Figure 3 These are microscopic images of composite quartz sand bonded and cured using the foam sand-fixing agent provided in Example 1;

[0047] Figure 4 This is another microscopic image of the composite quartz sand bonded and cured using the foam sand-fixing agent provided in Example 1;

[0048] Figure 5 It is an indoor experimental device for simulating the bonding of sediment by injecting foam curing agent;

[0049] Figure 6 The foam sand-fixing agent provided in Example 1 simulates the cementing and sand-fixing effect around the brine discharge column indoors. Detailed Implementation

[0050] The technical solution of the present invention will be further described below with reference to the accompanying drawings and specific embodiments. Those skilled in the art should understand that the embodiments described are merely illustrative of the present invention and should not be considered as specific limitations thereof.

[0051] The sources of some components in the following examples and comparative examples are as follows:

[0052] (1) Epoxy resin E51: Jinan Rongxin Fine Chemical Co., Ltd., industrial grade, molecular weight 392;

[0053] (2) Dodecylphenol polyoxyethylene ether: Shandong Jintai Hongfa Biotechnology Co., Ltd., molecular weight 646;

[0054] (3) Nano silica: Nanjing Baoket New Materials Co., Ltd., particle size 20nm;

[0055] (4) 4-Methyl-1,2-cyclohexanediol: Hubei Yunmei Technology Co., Ltd.;

[0056] (5) PVA1788: Guangzhou Qihua Chemical Co., Ltd.

[0057] Example 1

[0058] A foam-based sand-fixing agent comprises 100 parts by weight of epoxy resin E51, 33 parts by weight of 4-methyl-1,2-cyclohexanediol, 10 parts by weight of 2,4,6-tris(dimethylaminomethyl)phenol (DMP-30), 6 parts by weight of dodecylphenol polyoxyethylene ether, 2 parts by weight of dodecyl dimethylamine acetone, 2 parts by weight of PVA1788, 0.5 parts by weight of nano-silica, and 80 parts by weight of distilled water.

[0059] A method for preparing a foamed sand-stabilizing agent, the method comprising the following steps:

[0060] (1) Epoxy resin E51 and dodecylphenol polyoxyethylene ether are mixed and emulsified at 8000 r / min, the emulsification temperature is 70℃ and the emulsification time is 5 min to obtain an emulsion. Distilled water is added to the emulsion to obtain a base liquid with a viscosity of 0.5 Pa·s.

[0061] (2) The base liquid obtained in step (1), 4-methyl-1,2-cyclohexanediol, DMP-30, dodecyl dimethylamine hydantoin, PVA1788 and nano silica are mixed to obtain the foam sand-fixing agent.

[0062] Examples 2-5

[0063] A foam sand-fixing agent, which differs from Example 1 only in the addition amount of dodecyl dimethylamine acetone being 1 part by weight, 1.5 parts by weight, 2.5 parts by weight, and 3 parts by weight, respectively, while the other components and addition amounts are the same as in Example 1.

[0064] A method for preparing a foam sand-fixing agent, which differs from Example 1 only in that the amount of dodecyl dimethylamine acetone added in step (2) is the same as that provided in Examples 2-5, while the other process parameters and steps are the same as in Example 1.

[0065] Examples 6-10

[0066] A foaming sand-fixing agent, which differs from Example 1 only in the amount of distilled water added, which is 40 parts by weight, 60 parts by weight, 100 parts by weight, 120 parts by weight and 140 parts by weight respectively. The other components and the amount added are the same as in Example 1.

[0067] A method for preparing a foamed sand-fixing agent, which differs from Example 1 only in that the amount of distilled water added in step (1) is the amount provided in Examples 6-10, and the base liquid viscosities are 2 Pa·s, 1 Pa·s, 0.2 Pa·s, 0.1 Pa·s and 0.05 Pa·s, respectively. The remaining process parameters and steps are the same as in Example 1.

[0068] Example 11

[0069] A foamed sand-fixing agent, which differs from Example 1 only in that the amount of DMP-30 added is 5 parts by weight, while the other components and the amount added are the same as in Example 1.

[0070] A method for preparing a foamed sand-fixing agent, which differs from Example 1 only in that the amount of DMP-30 added in step (2) is the amount provided in this example, while the other process parameters and steps are the same as in Example 1.

[0071] Comparative Example 1

[0072] A foaming sand-fixing agent, which differs from Example 1 only in that the amount of dodecyl dimethylamine acetone added is 0.5 parts by weight, while the other components and their amounts are the same as in Example 1.

[0073] A method for preparing a foam sand-fixing agent, which differs from Example 1 only in that the amount of dodecyl dimethylamine acetone added in step (2) is the same as the amount provided in this comparative example, and the remaining process parameters and steps are the same as in Example 1.

[0074] Comparative Example 2

[0075] A foamed sand-fixing agent, which differs from Example 1 only in that the amount of DMP-30 added is 15 parts by weight, while the other components and amounts added are the same as in Example 1.

[0076] A method for preparing a foamed sand-fixing agent, which differs from Example 1 only in that the amount of DMP-30 added in step (2) is the same as the amount provided in this comparative example, while the other process parameters and steps are the same as in Example 1.

[0077] Performance testing of foamed sand-stabilizing agent:

[0078] (1) Foaming performance test: The foam slurry agents provided in Examples 1-10 and Comparative Example 1 were stirred at 8000 rad / min for 5 min, and the comprehensive foam value of the foam slurry agents was tested. The specific test method for the comprehensive foam value can be found in CN102455350A; the results are as follows. Figure 1 Bar charts of foaming performance of foamed sand-stabilizing agents provided in Examples 1-5 and Comparative Example 1 Figure 2 The bar charts showing the foaming performance of the foamed sand-stabilizing agents provided in Examples 1 and 6-10 are as follows: Figure 1It can be seen that there is an optimal value for the amount of dodecyl dimethylamine acetate added, which is determined by the critical micelle concentration (CMC). When the amount of dodecyl dimethylamine acetate added is 2 parts by weight, the foaming effect of the foaming sand fixation agent is the best.

[0079] Depend on Figure 2 It can be seen that as the proportion of distilled water in the foam slurry increases, the foaming effect of the foam slurry first improves and then deteriorates. When the ratio of epoxy resin to distilled water is 5:4, the foaming effect of the foam slurry is the best. This is mainly because the higher the proportion of epoxy resin, the higher the viscosity of the base liquid, and the more difficult it is to foam, thus the foaming effect of the foam slurry deteriorates. When the proportion of distilled water in the base liquid increases, on the one hand, the viscosity of the base liquid decreases, which is conducive to foaming; on the other hand, more liquid film can be formed, resulting in an increase in foam volume and a better foaming effect. However, when the proportion of distilled water continues to increase, the viscosity of the liquid film decreases, the foam drainage rate increases, the half-life decreases, the foam stability deteriorates, and the foaming effect deteriorates. In addition, the increase in the proportion of distilled water will lead to a decrease in the resin content in the foam slurry, thereby affecting the slurry strength. Therefore, the proportion of distilled water in the foam slurry has an important impact on the foaming effect.

[0080] (2) Curing test: The foam sand-fixing agents provided in Example 1, Example 11 and Comparative Example 2 were poured into the same container, which contained 100g of a combination of quartz sand with different particle sizes, and the gaps between the combination of quartz sand were filled with saturated brine (concentration 25%, density 1.22g / cm³). 3 The curing process was carried out at 50℃, and the curing results are shown in Table 1. Figure 3 Microscopic images of composite quartz sand bonded and cured using the foam-based sand-fixing agent provided in Example 1 and Figure 4 Another microscopic image of the composite quartz sand bonded and cured using the foam sand-fixing agent provided in Example 1 is shown:

[0081] Table 1

[0082]

[0083] Table 1 shows that when the addition amount of accelerator DMP-30 is 10 parts by weight, the shortest curing time of the foam slurry is 2 days; Figure 3 and Figure 4 It can be seen that the sand body is uniformly and firmly consolidated using the foam sand-fixing agent provided in Example 1.

[0084] (3) Sand-fixing and sand-prevention performance test: The sand-fixing and sand-prevention performance of the foam sand-fixing agent provided in Example 1 was tested through a simulation experiment. The simulation experiment device is as follows: Figure 5The indoor simulation device for injecting foam curing agent into sediment is shown. The simulation process is as follows: ① A glass sand-filled tube is used to simulate a salt cavern cavity, and an organic glass tube is pre-placed in the center to simulate a brine discharge column; 100g of a combination of quartz sand of different particle sizes is filled into the glass sand-filled tube, and the quartz sand is filled with saturated brine to simulate sediment at the bottom of the cavity; ② The entire simulation device is placed in a water bath constant temperature chamber, and the water bath temperature is controlled at about 50℃. The water bath temperature can be adjusted and controlled in real time according to experimental needs; ③ The foam curing agent provided in Example 1 is injected into the glass sand-filled tube through a syringe, and after 2 days of curing, the foam curing agent is injected into the sediment in the salt cavern to cement and solidify the sediment particles around the brine discharge column; ④ The injection is simulated by pushing the syringe handle downward. The process involves continuously injecting saturated brine from a syringe into a glass sand-filled tube. This drives the saturated brine and small-particle quartz sand within the tube through the cemented and solidified sediment into the brine discharge column and then into a conical flask. The outflow of water and sand from the conical flask is observed. ⑤ When the conical flask is filled with 250 mL of brine, the injection and discharge time and the sand flow are measured and recorded. ⑥ After four measurements, the simulation experiment is stopped. The glass sand-filled tube is opened, and the internal acrylic tube is removed to observe the cementation of the surrounding sand particles. ⑦ Based on the experimental data, including the cementation of the quartz sand around the acrylic tube and the sand flow in the conical flask, the sand-fixing and sand-prevention effects of the foam sand-fixing agent provided by this invention in simulating brine discharge from a salt cavity can be comprehensively analyzed. The simulation results are shown in Table 2 and... Figure 6 The effect of the foam sand-fixing agent provided in Example 1 on the cementation and sand-fixing around the brine discharge pipe column in an indoor simulation is shown:

[0085] Table 2

[0086] 1 25.5 0.19 2 78.6 0.01 3 160 0.03 4 450 0.22 total 714.1 0.45

[0087] From Table 2 and Figure 6 It can be seen that when a total of 1000mL of brine is discharged, the total time is 714.1s, the total amount of sand discharged is 0.45g, and the sand discharge rate is only 0.45%. The foam sand-fixing agent provided by this invention has good foaming and bonding properties. After adsorbing and bonding the sediment particles around the brine discharge column, the sand-proof barrier formed has good permeability and good sand-proof effect.

[0088] The applicant declares that the detailed process flow of this invention is illustrated by the above embodiments, but this invention is not limited to the above detailed process flow, that is, it does not mean that this invention must rely on the above detailed process flow to be implemented. Those skilled in the art should understand that any improvements to this invention, equivalent substitutions of raw materials for the product of this invention, addition of auxiliary components, and selection of specific methods, etc., all fall within the protection scope and disclosure scope of this invention.

Claims

1. A salt-resistant foam sand-stabilizing agent, characterized in that, The salt-resistant foam sand-stabilizing agent comprises the following components in parts by weight: Epoxy resin E51100 parts by weight 25-35 parts by weight of curing agent 5-6 parts by weight of emulsifier 1-3 parts by weight of foaming agent Foam stabilizer 0.75-4 parts by weight, Accelerator 1-13 parts by weight; The salt-resistant foam sand-fixing agent also includes a solvent; The mass ratio of the epoxy resin to the solvent is 1:(0.4-0.8). The solvent includes water; The foam stabilizer includes a combination of polymeric foam stabilizer and particulate foam stabilizer, wherein the polymeric foam stabilizer includes any one of PEG-2000, PEG-6000, PEG-10000, PVA1788 or hydroxyethyl cellulose.

2. The salt-resistant foam sand-stabilizing agent according to claim 1, characterized in that, The curing agent includes acid anhydrides and / or amines.

3. The salt-resistant foam sand-stabilizing agent according to claim 2, characterized in that, The acid anhydrides include 4-methyl-1,2-cyclohexanediol.

4. The salt-resistant foam sand-stabilizing agent according to claim 2, characterized in that, The amines include any one or a combination of at least two of the following: 650 epoxy resin curing agent, 651 epoxy resin curing agent, or H-113 modified aromatic amine epoxy curing agent.

5. The salt-resistant foam sand-stabilizing agent according to claim 1, characterized in that, The emulsifier includes dodecylphenol polyoxyethylene ether.

6. The salt-resistant foam sand-stabilizing agent according to claim 1, characterized in that, The foaming agent includes any one or a combination of at least two of polysorbate-80, sodium lauryl sulfate, lauramide propyl hydroxysulfonate betaine, or dodecyl dimethylamine hydantoin.

7. The salt-resistant foam sand-stabilizing agent according to claim 6, characterized in that, The foaming agent is dodecyl dimethylamine acetyl lactone.

8. The salt-resistant foam sand-stabilizing agent according to claim 1, characterized in that, The polymeric foam stabilizer is 0.5-3 parts by weight.

9. The salt-resistant foam sand-stabilizing agent according to claim 1, characterized in that, The particulate foam stabilizer includes nano-silica.

10. The salt-resistant foam sand-stabilizing agent according to claim 1, characterized in that, The accelerator includes any one or a combination of at least two of 2,4,6-tris(dimethylaminomethyl)phenol, methyl dibenzylamine, or organophosphorus / bromine complexes.

11. A method for preparing an anti-salt foaming sand-stabilizing agent as described in any one of claims 1 to 10, characterized in that, The preparation method includes the following steps: (1) The epoxy resin and the emulsifier are mixed and emulsified to obtain an emulsion. A solvent is added to the emulsion to obtain a base liquid. (2) The base liquid, curing agent, accelerator, foaming agent and foam stabilizer obtained in step (1) are mixed to obtain the salt-resistant foam sand-fixing agent.

12. The preparation method according to claim 11, characterized in that, The emulsification temperature is 70-80℃.

13. The preparation method according to claim 11, characterized in that, The emulsification time is 5-30 minutes.

14. The preparation method according to claim 11, characterized in that, The emulsification is carried out under stirring.

15. The preparation method according to claim 14, characterized in that, The stirring speed is 5000-8000 r / min.

16. The preparation method according to claim 11, characterized in that, The viscosity of the base liquid is 0.05-2 Pa·s.

17. An application of the salt-resistant foam sand-stabilizing agent as described in any one of claims 1 to 10, characterized in that, The application of the salt-resistant foam slag-fixing agent in the expansion of brine drainage from the bottom of salt cavern gas storage tanks.

18. The application according to claim 17, characterized in that, The curing temperature of the salt-resistant foam sintering agent is 25-50℃.

19. The application according to claim 17, characterized in that, The curing time of the salt-resistant foam sand-fixing agent is 2-5 days.

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