Temperature-sensitive plugging agent and preparation method thereof
By using temperature-sensitive plugging regulators of polyethylene glycol glycidyl ether, polyethylene polyamine and water, the problem of the existing polyacrylamide gel-type plugging regulators being affected by injection factors has been solved, and it has been achieved in conventional reservoirs. Excellent plugging performance and adaptability within the temperature range.
Patent Information
- Application Number
- CN202310893493.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2023-07-20
- Publication Date
- 2025-01-21
Abstract
Description
Technical Field
[0001] The present invention relates to the field of chemical water plugging and profile control in oil fields, and in particular to a plugging control agent. Background Art
[0002] The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.
[0003] At present, the commonly used plugging agent in oil fields is mainly polyacrylamide gel. Because its system contains long-chain structure and metal ions, it is affected by factors such as chromatographic separation effect, ion adsorption and shear dilution. If the injection factors such as ion adsorption and shear dilution change, the concentration of the cross-linking agent will be reduced by more than 15%, thus affecting the plugging effect. In view of the above problems, oil fields are in urgent need of developing a temperature-sensitive plugging agent that is not affected by injection factors, is only sensitive to temperature, has excellent plugging performance, can be used for conventional reservoir profile control and water plugging operations, and can also be used as a post-segment plug for traditional plugging agents.
[0004] It should be noted that the information disclosed in the above background technology section is only used to enhance the understanding of the background of the present disclosure, and therefore may contain information that does not constitute prior art. Summary of the invention
[0005] In view of this, the present disclosure provides a temperature-sensitive plugging agent to solve the problem that the existing polyacrylamide gel plugging agent is easily affected by injection factors, resulting in a decrease in cross-linking concentration and a decrease in the compressive strength of the gel, thereby affecting the plugging effect.
[0006] In the first aspect, the temperature-sensitive plugging agent comprises: Polyethylene glycol glycidyl ether, polyethylene polyamine and water.
[0007] In the present disclosure and possible embodiments, the mass of the polyethylene polyamine is 0.02 to 0.04 times the mass of the polyethylene glycol glycidyl ether.
[0008] In the present disclosure and possible embodiments, the mass of the polyethylene polyamine is 0.02, 0.03 or 0.04 times the mass of the polyethylene glycol glycidyl ether; and / or, The polyethylene polyamine is diethylene triamine or triethylene tetramine.
[0009] In the present disclosure and possible embodiments, the method for preparing polyethylene glycol glycidyl ether comprises: A phase transfer catalyst is added to a polyethylene glycol aqueous solution at a certain temperature, epichlorohydrin is dripped into the system under stirring, and then a base is added to react by heating. The reaction product is filtered and distilled to obtain the polyethylene glycol glycidyl ether.
[0010] In the present disclosure and possible embodiments, the phase transfer catalyst is tetrabutylammonium bromide; and / or, The certain temperature is 35°C to 50°C, and the temperature increase is to 55°C to 60°C; and / or, The molar ratio of the polyethylene glycol to the epichlorohydrin is 1:3 to 1:5; and / or, The amount of the phase transfer catalyst used is 0.03 to 0.05 times the amount of the epichlorohydrin used.
[0011] In the present disclosure and possible embodiments, the molar ratio is 1:3, 1.4 or 1:5, and the amount of the phase transfer catalyst is 0.03, 0.04 or 0.05 times the amount of epichlorohydrin; and / or, The molecular weight of the polyethylene glycol is 600-1000; and / or, The alkali is sodium hydroxide, and the amount of the alkali used is 0.2 to 0.5 times the amount of the epichlorohydrin used.
[0012] In the present disclosure and possible embodiments, the amount of the base used is 0.2, 0.3, 0.4 or 0.5 times the amount of epichlorohydrin used; and / or, The distillation is vacuum distillation, which is performed twice. The vacuum distillation temperature is 55° C., the negative pressure of the vacuum pump is -1 MPa, anhydrous ethanol is used during the distillation, and the light yellow substance remaining after the distillation is the polyethylene glycol glycidyl ether.
[0013] In a second aspect, a method for preparing the temperature-sensitive plugging agent according to the first aspect comprises: Polyethylene polyamine is added to the aqueous solution of polyethylene glycol glycidyl ether, and the reaction is carried out at a certain temperature and time, and the reaction product is the temperature-sensitive plugging agent.
[0014] In the present disclosure and possible embodiments, the mass concentration of the polyethylene glycol glycidyl ether aqueous solution is 10-25%; and / or, The temperature is 40° C. to 60° C., and the time is 16 to 72 hours.
[0015] In the present disclosure and possible embodiments, the mass concentration is 10%, 12%, 16%, 20% or 25%; The temperature is 40°C, 45°C, 50°C, 55°C or 60°C; The time period is 16, 24, 36, 48, 60 or 72 hours.
[0016] The temperature-sensitive plugging agent disclosed in the present invention does not contain metal ions and polymer long chains in its structure, so the plugging effect is not affected by factors such as chromatographic separation effect, ion adsorption and shear dilution, and the performance results of the compressive strength, storage modulus and core plugging rate of the gelled material fully meet the standard requirements of plugging agents for oil field construction. In addition, the conventional reservoir temperature range is 40°C to 60°C, and the plugging agent disclosed in the present invention can prepare a series of temperature-sensitive plugging agents with adjustable gelling temperature within the range of 40°C to 60°C by changing the concentration of the gel solution, thereby meeting the plugging demand at any temperature within the conventional reservoir temperature range. In addition, the synthetic process of the plugging agent disclosed in the present invention uses low-priced raw materials with a wide range of sources. Implementation
[0017] The present disclosure is described below based on embodiments, but it is worth noting that the present disclosure is not limited to these embodiments. In the detailed description of the present disclosure below, some specific details are described in detail. However, for the parts that are not described in detail, those skilled in the art can also fully understand the present disclosure.
[0018] At the same time, unless the context clearly requires otherwise, the words "include", "comprises" and similar words throughout the specification and claims should be interpreted as inclusive rather than exclusive or exhaustive; that is, the meaning is "including but not limited to". Example
[0019] 1. Composition of temperature-sensitive plugging agent In this embodiment, a temperature-sensitive plugging agent with a reservoir temperature of 40° C. is pre-configured, and the weight percentage of its components is designed to be: 24.5% of polyethylene glycol glycidyl ether, 0.5% of diethylenetriamine, and 75% of water.
[0020] 2. The preparation method of temperature-sensitive plugging agent is as follows: 1. Synthesis of polyethylene glycol glycidyl ether: 50 g of polyethylene glycol (molecular weight 1000) was added to a three-necked flask with stirring, reflux condenser and constant pressure dropping funnel, and stirred at 50 °C and 500 r / min until the polyethylene glycol was dissolved; 0.6 g of tetrabutylammonium bromide was added under the same conditions; then 18.5 g of epichlorohydrin was slowly added to the reaction solution at 0.5 drops / second using a constant pressure dropping funnel; after stirring for 5 min, the temperature was raised to 60 °C; 9 g of solid sodium hydroxide was added and reacted for 6 h; the solution was filtered twice while hot using a Buchner funnel, and the liquid in the suction flask was retained; finally, the liquid in the suction flask was transferred to a single-necked flask and distilled under reduced pressure twice, the reduced pressure distillation temperature was set to 55 °C, the negative pressure of the circulating water vacuum pump was -1 MPa, and 30 mL of anhydrous ethanol was added during each distillation to obtain a light yellow product, polyethylene glycol glycidyl ether.
[0021] 2. Take 4.89 g of the prepared polyethylene glycol glycidyl ether and prepare it into an aqueous solution with a mass concentration of 25%.
[0022] 3. Add 0.1 g of diethylenetriamine and react with the prepared 25% mass concentration of polyethylene glycol glycidyl ether aqueous solution at a temperature of 40°C for 16 hours to obtain the temperature-sensitive plugging agent WMD-40.
[0023] 3. Performance test of temperature-sensitive plugging agent 1. Gelation temperature sensitivity test In order to test the temperature response performance of the temperature-sensitive plugging agent of this embodiment and the strength of the elastic body after gelation, the temperature-sensitive plugging agent was taken and subjected to UV and compressive strength tests: the experimental results show that when the transmittance of the WMD-40 system was tested by UV, when the test temperature gradually increased to 40°C, the transmittance decreased significantly. At this time, the temperature is the phase transition temperature point of the gel system, and the system begins to undergo a phase transition and gradually becomes an elastomer; it can be seen that the phase transition temperature point of the gel system of this embodiment is 40°C, which meets the requirement that the reservoir temperature is 40°C.
[0024] 2. Determination of compressive strength In the gel strength test, the gelled plugging agent (length 40mm × width 30mm) is placed at the center of the lower support block of the upper part of the testing machine as required, and the two end faces are kept flat. The pressure when pressed down 1cm is the compressive strength of the plugging agent. A group of strength test specimens should not be less than 3 pieces, and the average value is taken and accurate to 0.1N. The compressive strength is greater than or equal to 8N. The test result shows that the compressive strength of WMD-40 is 14.2N.
[0025] 3. Storage modulus determination The storage modulus was measured by a rheometer using the standard method published in SY / T 6296-2013 to determine the strength of the plugging agent of this embodiment.
[0026] The temperature-sensitive plugging agent WMD-40 sample was subjected to three parallel oscillation time sweep tests to obtain the average value of the sample storage modulus G'. Among them, the plugging agent with G' less than 1 Pa is defined as weak strength, the plugging agent with G' between 1 Pa and 10 Pa is classified as medium strength, and the plugging agent with G' greater than 10 Pa is judged as high strength plugging agent. According to the standard, the test result shows that the storage modulus of WMD-40 is 7.6 Pa, which meets the standard requirements for plugging agents used in oilfield construction.
[0027] 4. Determination of core plugging rate A Φ2.5 cm × 20 cm sand-filled tube physical simulation experimental device was used, and the permeability range was selected as 0.5 μm. 2The sand-filled pipes on the left and right were used as simulated cores for the test. WMD-40 temperature-sensitive plugging agent was continuously injected into the simulated cores, and the displacement pressure difference began to rise significantly (305.29 kPa) and liquid always flowed out from the output end, indicating that WMD-40 temperature-sensitive plugging agent has excellent injection performance. After subsequent water flooding of multiple pore volumes, the displacement pressure difference is still much greater than the initial injection pressure. The plugging rate of WMD-40 temperature-sensitive plugging agent for simulated cores reached 83.46%, which meets the standard requirements for plugging agents used in oilfield construction. Example
[0028] 1. Composition of temperature-sensitive plugging agent In this embodiment, a temperature-sensitive plugging agent with a reservoir temperature of 45° C. is pre-configured, and the mass percentage of each component is designed to be: 9.6% of polyethylene glycol glycidyl ether, 0.4% of triethylenetetramine, and 90% of water.
[0029] 2. Preparation method of temperature-sensitive plugging agent 1. Synthesis of polyethylene glycol glycidyl ether: 30 g of polyethylene glycol (molecular weight 600) was added to a three-necked flask equipped with a stirrer, a reflux condenser and a constant pressure dropping funnel, and stirred at 35 °C and 400 r / min until the polyethylene glycol was dissolved; 1.2 g of tetrabutylammonium bromide was added under the same conditions; then 23.13 g of epichlorohydrin was added dropwise to the reaction solution at 0.5 drops / second using a constant pressure low liquid funnel; after stirring for 5 min, the temperature was raised to 55 °C; 6 g of solid sodium hydroxide was added and reacted for 4 h; the mixture was filtered twice while hot using a Buchner funnel, and the liquid in the suction flask was retained; finally, the liquid in the suction flask was transferred to a single-necked flask and distilled under reduced pressure twice, the temperature of the reduced pressure distillation was set to 55 °C, the negative pressure of the circulating water vacuum pump was -1 MPa, and 30 mL of anhydrous ethanol was added during each distillation to obtain a light yellow product, polyethylene glycol glycidyl ether.
[0030] 2. Take 2.34 g of the obtained polyethylene glycol glycidyl ether and prepare it into a 10% mass concentration aqueous solution.
[0031] 3. Add 0.1 g of triethylenetetramine and react with a 10% mass concentration of polyethylene glycol glycidyl ether aqueous solution at 45°C for 72 hours to obtain a temperature-sensitive plugging agent WMD-45.
[0032] 3. Performance test of temperature-sensitive plugging agent 1. Gelation temperature sensitivity test The transmittance of the WMD-45 system was tested by ultraviolet light. When the test temperature gradually increased to 45°C, the transmittance decreased significantly. At this time, the temperature is the phase transition temperature of the gel system. The system begins to undergo a phase transition and gradually becomes an elastomer. The phase transition temperature of the gel system in this embodiment is 45°C, which meets the requirement that the reservoir temperature is 45°C.
[0033] 2. Determination of compressive strength The test results of the gel strength are as follows: the compressive strength of WMD-45 is 10.8N. Example
[0034] 1. Composition of temperature-sensitive plugging agent In this embodiment, a temperature-sensitive plugging agent with a reservoir temperature of 60° C. is pre-configured, and the mass percentage of its components is: 9.6% of intermediate polyethylene glycol glycidyl ether, 0.4% of triethylenetetramine, and 90% of water.
[0035] 2. Preparation method of temperature-sensitive plugging agent 1. Synthesis of polyethylene glycol glycidyl ether: 30 g of polyethylene glycol (molecular weight 600) was added to a three-necked flask equipped with a stirrer, a reflux condenser and a constant pressure dropping funnel, and stirred at 35 °C and 400 r / min until the polyethylene glycol was dissolved; 1.2 g of tetrabutylammonium bromide was added under the same conditions; then 23.13 g of epichlorohydrin was added dropwise to the reaction solution at 0.5 drops / second using a constant pressure low liquid funnel; after stirring for 5 min, the temperature was raised to 55 °C; 6 g of solid sodium hydroxide was added and reacted for 4 h; the mixture was filtered twice while hot using a Buchner funnel, and the liquid in the suction flask was retained; finally, the liquid in the suction flask was transferred to a single-necked flask and distilled under reduced pressure twice, the temperature of the reduced pressure distillation was set to 55 °C, the negative pressure of the circulating water vacuum pump was -1 MPa, and 30 mL of anhydrous ethanol was added during each distillation to obtain a light yellow product, polyethylene glycol glycidyl ether.
[0036] 2. Take 2.34 g of the prepared polyethylene glycol glycidyl ether and prepare it into an aqueous solution with a mass concentration of 10%.
[0037] 3. Add 0.1 g of triethylenetetramine and react with the prepared 10% mass concentration of polyethylene glycol glycidyl ether aqueous solution at a temperature of 60°C for 72 hours to obtain the temperature-sensitive plugging agent WMD-60.
[0038] 3. Performance test of temperature-sensitive plugging agent 1. Gelation temperature sensitivity test The transmittance of the WMD-60 system was tested by ultraviolet light. When the test temperature gradually increased to 60°C, the transmittance decreased significantly. At this time, the temperature is the phase transition temperature of the gel system. The system begins to undergo a phase transition and gradually becomes an elastomer. The phase transition temperature of the gel system in this embodiment is 60°C, which meets the requirement that the reservoir temperature is 60°C.
[0039] 2. Determination of compressive strength In the gel strength test, the test result showed that the compressive strength of WMD-60 was 8.6N.
[0040] 3. Storage modulus determination The storage modulus was measured by a rheometer using the standard method published in SY / T 6296-2013 to determine the strength of the plugging agent of this embodiment.
[0041] The temperature-sensitive plugging agent WMD-40 sample was subjected to three parallel oscillation time sweep tests to obtain the average value of the sample storage modulus G'. Among them, the plugging agent with G' less than 1 Pa is defined as weak strength, the plugging agent with G' between 1 Pa and 10 Pa is classified as medium strength, and the plugging agent with G' greater than 10 Pa is judged as high strength plugging agent. According to the standard, the test result shows that the storage modulus of WMD-60 is 9.1 Pa, which meets the standard requirements for plugging agents used in oilfield construction.
[0042] 4. Determination of core plugging rate A Φ2.5 cm × 20 cm sand-filled tube physical simulation experimental device was used, and the permeability range was selected as 0.5 μm. 2 The sand-filled pipes on the left and right were used as simulated cores for the test. WMD-60 temperature-sensitive plugging agent was continuously injected into the simulated cores, and the displacement pressure difference began to rise significantly (398.11 kPa) and liquid always flowed out from the output end, indicating that WMD-60 temperature-sensitive plugging agent has excellent injection performance. After subsequent water flooding of multiple pore volumes, the displacement pressure difference is still much greater than the initial injection pressure. The plugging rate of WMD-60 temperature-sensitive plugging agent for simulated cores reached 86.95%, which meets the standard requirements for plugging agents used in oilfield construction.
[0043] It can be seen from the above examples that by changing the concentration of the gel solution, a series of temperature-sensitive plugging agents with adjustable gelling temperature in the range of 40°C to 60°C can be prepared, which meets the plugging control requirements at any temperature within the conventional reservoir temperature range of 40°C to 60°C, and can be used for conventional reservoir profile control and water plugging operations, and can also be used as a post-segment plug for traditional plugging agents.
[0044] The above-described embodiments are only embodiments of the present disclosure, and the descriptions thereof are relatively specific and detailed, but they cannot be construed as limiting the scope of the present disclosure. It should be noted that, for a person of ordinary skill in the art, without departing from the concept of the present disclosure, several variations, equivalent substitutions, improvements, etc. may be made, all of which fall within the scope of protection of the present disclosure. Therefore, the scope of protection of the present disclosure shall be subject to the attached claims.
Claims
1. A temperature-sensitive plugging agent, characterized in that: Its composition includes: Polyethylene glycol glycidyl ether, polyethylene polyamine and water.
2. The temperature-sensitive plugging agent according to claim 1, characterized in that: The mass of the polyethylene polyamine is 0.02 to 0.04 times the mass of the polyethylene glycol glycidyl ether.
3. The temperature-sensitive plugging agent according to claim 2, characterized in that: The mass of the polyethylene polyamine is 0.02, 0.03 or 0.04 times the mass of the polyethylene glycol glycidyl ether; and / or, The polyethylene polyamine is diethylene triamine or triethylene tetramine.
4. The temperature-sensitive plugging agent according to claim 3, characterized in that: The preparation method of the polyethylene glycol glycidyl ether comprises: A phase transfer catalyst is added to a polyethylene glycol aqueous solution at a certain temperature, epichlorohydrin is dripped into the system under stirring, and then a base is added to react by heating. The reaction product is filtered and distilled to obtain the polyethylene glycol glycidyl ether.
5. The temperature-sensitive plugging agent according to claim 4, characterized in that: The phase transfer catalyst is tetrabutylammonium bromide; and / or, The certain temperature is 35°C to 50°C, and the temperature increase is to 55°C to 60°C; and / or, The molar ratio of the polyethylene glycol to the epichlorohydrin is 1:3 to 1:5; and / or, The amount of the phase transfer catalyst used is 0.03 to 0.05 times the amount of the epichlorohydrin used.
6. The temperature-sensitive plugging agent according to claim 5, characterized in that: The molar ratio is 1:3, 1.4 or 1:5, and the amount of the phase transfer catalyst is 0.03, 0.04 or 0.05 times the amount of epichlorohydrin; and / or, The molecular weight of the polyethylene glycol is 600-1000; and / or, The alkali is sodium hydroxide, and the amount of the alkali used is 0.2 to 0.5 times the amount of the epichlorohydrin used.
7. The temperature-sensitive plugging agent according to claim 6, characterized in that: The amount of the base used is 0.2, 0.3, 0.4 or 0.5 times the amount of epichlorohydrin used; and / or, The distillation is vacuum distillation, which is performed twice. The vacuum distillation temperature is 55° C., the negative pressure of the vacuum pump is -1 MPa, anhydrous ethanol is used during the distillation, and the light yellow substance remaining after the distillation is the polyethylene glycol glycidyl ether.
8. The method for preparing the temperature-sensitive plugging agent according to any one of claims 1 to 7, characterized in that: include: Polyethylene polyamine is added to the aqueous solution of polyethylene glycol glycidyl ether, and the reaction is carried out at a certain temperature and time, and the reaction product is the temperature-sensitive plugging agent.
9. The method for preparing the temperature-sensitive plugging agent according to claim 8, characterized in that: The mass concentration of the polyethylene glycol glycidyl ether aqueous solution is 10-25%; and / or, The temperature is 40° C. to 60° C., and the time is 16 to 72 hours.
10. The method for preparing the temperature-sensitive plugging agent according to claim 8, characterized in that: The mass concentration is 10%, 12%, 16%, 20% or 25%; The temperature is 40°C, 45°C, 50°C, 55°C or 60°C; The time period is 16, 24, 36, 48, 60 or 72 hours.