Composite particles, methods for their preparation and use

Abstract

The application provides a composite particle, a preparation method and application thereof. The composite particle is obtained by reacting polyvinyl alcohol and a crosslinking agent containing a benzene ring under the action of a catalyst and filling a phenyl rubber. The composite particle provided by the application can resist high temperature (not less than 130 DEG C), resist high salt (mineralization degree not less than 210000 mg / L), has self-healing ability, can be secondarily adhered at high temperature, has strong deformation ability after adhesion, and can realize deep liquid flow diversion.

Description

Technical Field

[0001] This invention belongs to the field of oilfield water shut-off and profile control technology, and particularly relates to a composite particle, its preparation method and application. Background Technology

[0002] With the continuous development of water injection in oilfields, data shows that the average water cut of oil wells in my country has exceeded 80%, and the water cut of some wells has even reached over 90%. The continuous formation of well-drained channels for water injection in the reservoirs has led to serious water production problems, resulting in low control of injection wells, reduced oil recovery, severe scaling and corrosion of pipelines, and increased environmental pollution. These issues severely restrict the efficient development of oilfields, thus necessitating the research and development of more efficient and high-quality chemical water shut-off and profile control agents for oilfields.

[0003] Over the past few decades, domestic and international oilfield chemical profile control and water shut-off technologies have evolved from initial cement slurry water shut-off to resin-based water shut-off and profile control, and now to the mainstream water shut-off agent—water-soluble polymer gel-based plugging agents. The variety of oilfield water shut-off agents has become increasingly diversified. Most oilfields have complex geological structures with severe heterogeneity, extremely strong conductivity in dominant flow channels, and many wells exhibit high temperature and high salinity characteristics. Due to limitations in the effectiveness of water shut-off in fractured-vuggy reservoirs, existing profile control and water shut-off materials exhibit rapid water absorption and expansion, thus limiting injection depth. Once saturated with water, the materials are prone to breakage, hindering precise plugging and resulting in poor plugging performance. Furthermore, current water shut-off technologies suffer from high usage and cost. Therefore, research into deep profile control and flooding technologies, along with the development of novel temperature- and salt-resistant plugging agents for high-temperature and high-salinity reservoirs, is essential.

[0004] Rubber powder composite particles are a promising particle plugging agent, capable of functioning continuously under a wide temperature range during deep drilling, providing excellent plugging and filtration reduction effects. However, current rubber powder composite particles suffer from the following problems: In terms of performance, they lack sufficient temperature and salt resistance, and their stability deteriorates under the influence of formation temperature, salinity, and pressure. Regarding production processes, energy consumption is high; the modification of waste rubber composites requires reactions at high temperatures, and in some cases, mechanical stirring is necessary. The production equipment is complex, requiring significant initial investment, which hinders widespread adoption. In terms of production costs, the investment in waste rubber composite modified asphalt production lines is high. Due to poor storage and transportation stability, they are unsuitable for long-term storage and long-distance transportation. The relatively dense production sites increase production costs, and the entire production process is cumbersome and costly, making industrialization difficult.

[0005] Therefore, existing composite rubber powder plugging agents still have considerable room for improvement in terms of technology and performance. The development of high-performance fracture-type deep-seated plugging particles will undoubtedly have a positive impact on the development of fractured-vuggy carbonate reservoirs and ultimately on their economic benefits. Summary of the Invention

[0006] One aspect of the present invention provides a method for preparing composite particles, comprising the following steps:

[0007] 1) Polyvinyl alcohol, phenyl rubber, a crosslinking agent containing benzene rings and a first dispersant are mixed to obtain a first dispersion;

[0008] 2) Mix the first dispersion and the second dispersant to obtain the second dispersion;

[0009] 3) The second dispersion is reacted under the action of a catalyst to obtain the composite particles.

[0010] According to a specific embodiment of the present invention, the total mass of the polyvinyl alcohol and the first dispersant is 100%, the mass of the polyvinyl alcohol is 5 wt% to 10 wt%, the mass of the phenyl rubber is 5 wt% to 15 wt%, and the mass of the benzene ring-containing crosslinking agent is 1 wt% to 3 wt%; and / or

[0011] The ratio of the total mass of the polyvinyl alcohol and the benzene ring-containing crosslinking agent to the volume of the catalyst is (6 to 13):(1 to 3); and / or

[0012] The mass of the second dispersant is 2 to 4 times the total mass of the polyvinyl alcohol and the first dispersant.

[0013] According to one specific embodiment of the present invention, the polyvinyl alcohol is selected from polyvinyl alcohol 1788 and / or polyvinyl alcohol 1799.

[0014] According to a specific embodiment of the present invention, the phenyl rubber is styrene-butadiene rubber;

[0015] Preferably, the phenyl rubber is styrene-butadiene rubber powder that has passed through an 80-mesh sieve.

[0016] In this invention, the phenyl rubber is waste phenyl rubber powder, preferably styrene-butadiene rubber powder obtained by crushing waste tires made of styrene-butadiene rubber.

[0017] According to one specific embodiment of the present invention, the benzene ring-containing crosslinking agent is selected from at least one of terephthalaldehyde, dicumyl peroxide, p-toluenesulfonic acid, and p-toluenesulfonyl chloride; and / or

[0018] The catalyst is an inorganic strong acid;

[0019] Preferably, the catalyst is concentrated hydrochloric acid and / or concentrated sulfuric acid.

[0020] According to one specific embodiment of the present invention, the first dispersant is water.

[0021] According to one specific embodiment of the present invention, the second dispersant is a surfactant solution;

[0022] Preferably, the mass of the solvent in the surfactant solution is 100%, and the amount of the surfactant is 0.1 wt% to 0.5 wt%.

[0023] Preferably, the surfactant is at least one selected from Span-80, Span-60, Span-40, and polysorbate;

[0024] and / or

[0025] The solvent is at least one of carbon tetrachloride, propylene glycol, ethanol, diethyl ether, and petroleum ether.

[0026] According to a specific embodiment of the present invention, the mixing temperature in step 1) is 85°C to 95°C; and / or

[0027] In step 2), mixing is performed by stirring; and / or the stirring speed is 350 rpm to 400 rpm; and / or

[0028] In step 3), the reaction conditions are to react at 25°C to 40°C for 2 to 4 hours.

[0029] According to a specific embodiment of the present invention, in step 3), the reaction product obtained from the reaction is filtered, washed with methanol and then washed with water to obtain the composite particles.

[0030] The second aspect of the present invention provides a composite particle prepared by the method described in the first aspect of the present invention;

[0031] Preferably, the particle size of the composite particles is 10 to 60 mesh.

[0032] The application of composite particles prepared by the method described in one of the present inventions or composite particles described in the second of the present invention in water shut-off and profile control of high-temperature and high-salinity fractured-vuggy carbonate reservoirs, especially as a plugging agent;

[0033] Preferably, the high temperature is not lower than 130°C; and / or

[0034] The term "high salt" refers to a mineralization degree of not less than 210,000 mg / L.

[0035] The beneficial effects of this invention are:

[0036] To address the problems of high production cost, complex processes, excessively high preparation temperatures, poor temperature and salt resistance, and poor stability at high temperatures associated with existing composite rubber powder granule plugging agents, this invention provides a composite particle, its preparation method, and its application. The composite particle is obtained by reacting polyvinyl alcohol and a benzene ring-containing crosslinking agent under the action of a catalyst, followed by filling with phenyl rubber.

[0037] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0038] (1) The composite particles provided by the present invention are inexpensive to prepare, the raw materials are readily available, and the cost is saved;

[0039] (2) It solves the environmental pollution problem caused by the direct disposal of waste phenyl rubber, and the resources are reused, turning waste into treasure;

[0040] (3) Waste phenyl rubber has a high filler content, simple process equipment and steps, simple reaction conditions, and is easy to industrialize;

[0041] (4) Waste phenyl rubber is both a filler and a proppant, playing a role in buffering and supporting, giving the particles excellent toughness and good deformability. The density can be adjusted according to the rubber powder ratio, making the particles easy to suspend and carry.

[0042] (5) The composite particles are resistant to high temperature (not less than 130℃) and high salt (mineralization not less than 210000mg / L). The crosslinking agent containing benzene ring and the phenyl rubber have a synergistic effect, which enhances the high temperature resistance and high salt resistance of the composite particles.

[0043] (6) The composite particles can be bonded a second time at high temperature, and have strong deformation ability after bonding: In the aging test at 130℃ and 210000mg / L mineralization, the composite particles provided by the present invention begin to bond when the aging time is 3 to 6 days, moderately bond when the aging time is 27 to 36 days, and completely bond when the aging time is 43 to 54 days; after the aging time reaches 60 days, there is no large amount of dissolution, good chemical stability, and still has good elasticity, deformability and toughness, and can be used as a blockage agent to realize deep liquid flow diversion. Attached Figure Description

[0044] Figure 1 The infrared spectra of polyvinyl alcohol and the composite particles prepared in Example 2 are shown, where (a) is the infrared spectrum of polyvinyl alcohol and (b) is the infrared spectrum of the composite particles prepared in Example 2.

[0045] Figure 2 The thermogravimetric curves of the composite particles prepared in Example 1 and the ordinary particles prepared in Comparative Examples 1 and 2 are shown.

[0046] Figure 3The aging of the composite particles prepared in Examples 1 to 4 and the ordinary particles prepared in Comparative Examples 1 and 2 at 130°C and 210,000 mg / L mineralization is shown.

[0047] Figure 4 The adhesion of the composite particles prepared in Example 2 after aging at 130°C and 210,000 mg / L mineralization for 60 days is shown. Detailed Implementation

[0048] The present invention will be further described below with reference to the embodiments. However, the embodiments of the present invention are merely illustrative examples and should not be construed as limiting the present invention under any circumstances.

[0049] The styrene-butadiene rubber powder used in Examples 1 to 4 and Comparative Example 2 was obtained by crushing waste tires made of styrene-butadiene rubber and passing them through an 80-mesh sieve. The styrene-butadiene rubber powder that could pass through the 80-mesh sieve was collected.

[0050] Example 1

[0051] 5g of polyvinyl alcohol (PVA1799), 5g of styrene-butadiene rubber powder, and 1g of terephthalaldehyde were added to 95g of water and mixed at 95℃ for 2 hours. The mixture was then dispersed in 300g of carbon tetrachloride containing 0.1wt% Span-80 under vigorous stirring to form a water-in-oil dispersion system. The stirring speed was controlled at 350rpm. Subsequently, 1mL of concentrated hydrochloric acid was added as a catalyst, and the mixture was reacted at 25℃ for 4 hours to gradually form composite particles. The mixture was filtered, and the adhering carbon tetrachloride was washed off with methanol and then washed with water to obtain composite particles with a particle size mainly distributed between 10 and 60 mesh.

[0052] Example 2

[0053] 10g of polyvinyl alcohol (PVA1799), 15g of styrene-butadiene rubber powder, and 3g of terephthalaldehyde were added to 90g of water and mixed at 95℃ for 2 hours. The mixture was then dispersed in 200g of carbon tetrachloride containing 0.1wt% Span-80 under vigorous stirring to form a water-in-oil dispersion system. The stirring speed was controlled at 400rpm. Subsequently, 2mL of concentrated hydrochloric acid was added as a catalyst, and the mixture was reacted at 30℃ for 3 hours to gradually form composite particles. The mixture was filtered, and the adhering carbon tetrachloride was washed off with methanol and then washed with water to obtain composite particles with a particle size mainly distributed between 10 and 60 mesh.

[0054] Example 3

[0055] 10g of polyvinyl alcohol (PVA1788), 5g of styrene-butadiene rubber powder, and 2g of terephthalaldehyde were added to 90g of water and mixed at 85℃ for 2 hours. The mixture was then dispersed in 250g of carbon tetrachloride containing 0.1wt% Span-80 under vigorous stirring to form a water-in-oil dispersion system. The stirring speed was controlled at 350rpm. Subsequently, 2.5mL of concentrated hydrochloric acid was added as a catalyst, and the mixture was reacted at 30℃ for 3 hours to gradually form composite particles. The mixture was filtered, and the adhering carbon tetrachloride was washed off with methanol and then washed with water to obtain composite particles with a particle size mainly distributed between 10 and 60 mesh.

[0056] Example 4

[0057] 10g of polyvinyl alcohol (PVA1788), 10g of styrene-butadiene rubber powder, and 2g of terephthalaldehyde were added to 90g of water and mixed at 85℃ for 2 hours. The mixture was then dispersed in 300g of carbon tetrachloride containing 0.1wt% Span-80 under vigorous stirring to form a water-in-oil dispersion system. The stirring speed was controlled at 400rpm. Subsequently, 3mL of concentrated hydrochloric acid was added as a catalyst, and the mixture was reacted at 40℃ for 2 hours to gradually form composite particles. The mixture was filtered, and the adhering carbon tetrachloride was washed off with methanol and then washed with water to obtain composite particles with a particle size mainly distributed between 10 and 60 mesh.

[0058] Comparative Example 1

[0059] 5g of polyvinyl alcohol (PVA1799) and 1g of terephthalaldehyde were added to 95g of water and mixed at 95°C for 2 hours. The mixture was then dispersed in 300g of carbon tetrachloride containing 0.1wt% Span-80 under vigorous stirring to form a water-in-oil dispersion system. The stirring speed was controlled at 350rpm. Subsequently, 1mL of concentrated hydrochloric acid was added as a catalyst, and the mixture was reacted at 25°C for 4 hours to gradually form composite particles. The particles were filtered, and the adhering carbon tetrachloride was washed off with methanol and then washed with water to obtain ordinary particles.

[0060] Comparative Example 2

[0061] 5g of polyvinyl alcohol (PVA1799), 5g of styrene-butadiene rubber powder, and 1g of glutaraldehyde were added to 95g of water and mixed at 95°C for 2 hours. The mixture was then dispersed in 300g of carbon tetrachloride containing 0.1wt% Span-80 under vigorous stirring to form a water-in-oil dispersion system. The stirring speed was controlled at 350rpm. Subsequently, 1mL of concentrated hydrochloric acid was added as a catalyst, and the mixture was reacted at 25°C for 4 hours to gradually form composite particles. The particles were filtered, and the adhering carbon tetrachloride was washed off with methanol and then washed with water to obtain ordinary particles.

[0062] Test Example 1

[0063] Infrared spectra of polyvinyl alcohol and the composite particles prepared in Examples 1 to 4 were measured using an infrared spectrometer. The infrared spectrum of the composite particles prepared in Example 2 is used as an example for analysis here.

[0064] Figure 1 The infrared spectra of polyvinyl alcohol and the composite particles prepared in Example 2 are shown, where (a) is the infrared spectrum of polyvinyl alcohol and (b) is the infrared spectrum of the composite particles prepared in Example 2. It can be seen that the -OH stretching vibration band of polyvinyl alcohol is located at 3442 cm⁻¹. -1 The spectrum of the composite particles is at 871 cm⁻¹ -1 (for para-disubstituted benzene), 1100cm -1 The presence of a new absorption band at the (C-O-C group) indicates that polyvinyl alcohol and terephthalaldehyde underwent a chemical cross-linking reaction in the composite particles prepared in Example 2.

[0065] The infrared spectra of the composite particles prepared in Examples 1, 3, and 4 are similar to those of... Figure 1 Similar to (b) in Examples 1, 3 and 4, polyvinyl alcohol and terephthalaldehyde underwent chemical cross-linking reactions in the composite particles prepared in Examples 1, 3 and 4.

[0066] Test Example 2

[0067] Thermogravimetric analysis (TGA) was used to measure the thermogravimetric curves of the composite particles prepared in Examples 1 to 4 and the ordinary particles prepared in Comparative Examples 1 and 2 to evaluate their thermal stability. Here, the TGA curves of the composite particles prepared in Example 1 and the ordinary particles prepared in Comparative Examples 1 and 2 are used as examples for analysis.

[0068] Figure 2 The thermogravimetric curves (TGA) of the composite particles prepared in Example 1 and the ordinary particles prepared in Comparative Examples 1 and 2 are shown. As can be seen from the figure, the ordinary particles prepared in Comparative Example 1 without added styrene-butadiene rubber powder began to lose weight at approximately 250°C, and remained stable at 450°C, maintaining a mass of approximately 5%, corresponding to a weight loss rate of 95%. The ordinary particles prepared in Comparative Example 2 with glutaraldehyde as the crosslinking agent began to lose weight at approximately 230°C, and remained stable at 500°C, maintaining a mass of approximately 10%, corresponding to a weight loss rate of 90%. The composite particles prepared in Example 1 with benzene ring-containing crosslinking agent terephthalaldehyde and filled with styrene-butadiene rubber powder only began to decompose above 300°C, and the weight loss ended at 480°C, maintaining a mass of approximately 20%, corresponding to a weight loss rate of 80%. Comparing the thermogravimetric curves of the three, it can be seen that the thermal stability of the composite particles prepared in Example 1 is significantly better than that of the ordinary particles prepared in Comparative Examples 1 and 2. The terephthalaldehyde and phenyl rubber powder in the composite particles have a synergistic effect, which enhances the thermal stability of the composite particles and gives them good temperature resistance.

[0069] Test Example 3

[0070] High-temperature and high-salt aging experiments were conducted on the composite particles prepared in Examples 1 to 4 and the ordinary particles prepared in Comparative Examples 1 and 2 at 130℃ and 210,000 mg / L. The specific steps are as follows:

[0071] 5g of the composite particles prepared in Examples 1 to 4 and the ordinary particles prepared in Comparative Examples 1 and 2 were weighed and placed in pressure-resistant bottles containing 20mL of simulated water from the Tarim Basin with a mineralization of 210,000mg / L. The bottles were sealed and placed in an aging chamber at 130℃ for 60 days. For ordinary particles that had achieved complete adhesion within 30 days, the experiment was stopped after 30 days of aging. The adhesion state of the ordinary particles was observed and recorded. The experimental conditions for the composite particles and ordinary particles are as follows: Figure 3 As shown.

[0072] The aging conditions of the composite particles prepared in Examples 1 to 4 and the ordinary particles prepared in Comparative Examples 1 and 2 are as follows: Figure 3 As shown. From Figure 3 As can be seen, at 130℃ and 210,000 mg / L mineralization: the composite particles prepared in Example 1 began to agglomerate after approximately 3 days of aging, reached moderate agglomeration after approximately 27 days of aging, and were completely agglomerated after approximately 43 days of aging; the composite particles prepared in Example 2 began to agglomerate after approximately 6 days of aging, reached moderate agglomeration after approximately 36 days of aging, and were completely agglomerated after approximately 54 days of aging; the composite particles prepared in Example 3 began to agglomerate after approximately 4 days of aging, reached moderate agglomeration after approximately 29 days of aging, and were completely agglomerated after approximately 48 days of aging; the composite particles prepared in Example 4 began to agglomerate after approximately 4 days of aging, reached moderate agglomeration after approximately 33 days of aging, and were completely agglomerated after approximately 52 days of aging. The ordinary particles prepared in Comparative Example 1 began to agglomerate after aging at 130℃ and 210,000 mg / L mineralization for 1 day, reached moderate agglomeration after approximately 7 days, and achieved complete agglomeration after approximately 13 days. The ordinary particles prepared in Comparative Example 2 began to agglomerate after aging at 130℃ and 210,000 mg / L mineralization for approximately 1 day, reached moderate agglomeration after approximately 6 days, and achieved complete agglomeration after approximately 9 days. These results demonstrate that the composite particles prepared in Examples 1 to 4 are resistant to high temperature and high salt content and exhibit good self-healing ability under high temperature and high mineralization conditions.

[0073] Because the ordinary particles prepared in Comparative Examples 1 and 2 adhered too quickly, they completely adhered before the aging time reached 30 days. The experiments in Comparative Examples 1 and 2 were stopped after 30 days of aging to observe the state of the ordinary particles after complete adhesion. Observations revealed that the ordinary particles prepared in Comparative Example 1 could not be stretched after complete adhesion, exhibiting poor mechanical properties, poor chemical stability, and poor resistance to high temperatures and high salts. The ordinary particles prepared in Comparative Example 2 dissolved completely after achieving complete adhesion within 30 days of aging at 130℃ and 210,000 mg / L mineralization, exhibiting poor chemical stability and poor resistance to high temperatures and high salts.

[0074] After aging for 60 days, the composite particles prepared in Examples 1 to 4 were taken out and found that the four composite particles did not dissolve in large quantities after being completely bonded, had good chemical stability, and still had good elasticity, deformability and toughness. Figure 4 The composite particles prepared in Example 2, which were completely adhered after aging for 60 days, showed that even after complete adhesion, the composite particles maintained a certain spherical shape without excessive adhesion or significant dissolution. From the formulation, compared to Example 1, Comparative Example 1 lacked styrene-butadiene rubber powder in its raw materials, and Comparative Example 2 replaced the benzene ring-containing crosslinking agent terephthalaldehyde with glutaraldehyde. This resulted in the ordinary particles prepared in Comparative Examples 1 and 2 exhibiting excessively fast adhesion, poor chemical stability, poor mechanical properties, and poor high-temperature and high-salt resistance. This indicates that the benzene ring-containing crosslinking agent and phenyl rubber used in the method for preparing composite particles provided by this invention have a synergistic effect, contributing to the excellent high-temperature and high-salt resistance of the composite particles.

[0075] In summary, the composite particles provided by this invention are temperature and salt resistant (specifically 130℃, 210000mg / L mineralization), have self-healing ability, can re-adhere at high temperatures, have strong deformation ability, and can be used as a blockage regulator to achieve deep fluid flow diversion.

[0076] While the present invention has been described with reference to specific embodiments, those skilled in the art will understand that various changes can be made without departing from the true spirit and scope of the invention. Furthermore, numerous modifications can be made to the subject, spirit, and scope of the invention to suit specific situations, materials, material compositions, and methods. All such modifications are included within the scope of the claims of the present invention.

Claims

1. A method for preparing composite particles, comprising the following steps: 1) Polyvinyl alcohol, phenyl rubber, a crosslinking agent containing benzene rings and a first dispersant are mixed to obtain a first dispersion; 2) Mix the first dispersion and the second dispersant to obtain a second dispersion, wherein the second dispersion is a water-in-oil dispersion system; 3) The second dispersion is reacted under the action of a catalyst to obtain the composite particles; The total mass of the polyvinyl alcohol and the first dispersant is 100%, wherein the mass of the polyvinyl alcohol is 5 wt% to 10 wt%, the mass of the phenyl rubber is 5 wt% to 15 wt%, and the mass of the benzene ring-containing crosslinking agent is 1 wt% to 3 wt%. The first dispersant is water; The second dispersant is a surfactant solution, wherein the solvent in the surfactant solution is at least one of carbon tetrachloride, diethyl ether, and petroleum ether; The catalyst is an inorganic strong acid.

2. The method according to claim 1, characterized in that, The ratio of the total mass of the polyvinyl alcohol and the benzene ring-containing crosslinking agent to the volume of the catalyst is (6 to 13):(1 to 3); and / or The mass of the second dispersant is 2 to 4 times the total mass of the polyvinyl alcohol and the first dispersant.

3. The method according to claim 1 or 2, characterized in that, The polyvinyl alcohol is selected from polyvinyl alcohol 1788 and / or polyvinyl alcohol 1799.

4. The method according to claim 1 or 2, characterized in that, The phenyl rubber is styrene-butadiene rubber.

5. The method according to claim 4, characterized in that, The phenyl rubber is styrene-butadiene rubber powder that has passed through an 80-mesh sieve.

6. The method according to claim 1 or 2, characterized in that, The benzene ring-containing crosslinking agent is selected from at least one of terephthalaldehyde, diisopropylbenzene peroxide, p-toluenesulfonic acid, and p-toluenesulfonyl chloride.

7. The method according to claim 1 or 2, characterized in that, The catalyst is concentrated hydrochloric acid and / or concentrated sulfuric acid.

8. The method according to claim 1 or 2, characterized in that, The mass of the solvent in the surfactant solution is 100%, and the amount of the surfactant is 0.1 wt% to 0.5 wt%. The surfactant is at least one of Span-80, Span-60, Span-40 and polysorbate.

9. The method according to claim 1 or 2, characterized in that, The mixing temperature in step 1) is 85°C to 95°C; and / or In step 3), the reaction conditions are to react at 25°C to 40°C for 2 to 4 hours.

10. A composite particle prepared by the method of any one of claims 1 to 9.

11. The composite particles according to claim 10, characterized in that, The particle size of the composite particles is 10 to 60 mesh.

12. The application of the composite particles prepared by the method according to any one of claims 1 to 9 or the composite particles according to claim 10 or 11 in water shut-off and profile control of high-temperature, high-salinity fractured-vuggy carbonate reservoirs.

13. The application according to claim 12, characterized in that, The application is the use of the composite particles as a plugging agent in the water shut-off and profile control of the high-temperature, high-salinity fractured-vuggy carbonate reservoir. Wherein, the high temperature is not lower than 130°C; and / or The term "high salt" refers to a mineralization degree of not less than 210,000 mg / L.

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