CN110229266B - Preparation method of crosslinked polymer, modified calcium carbonate particles and plugging agent - Google Patents
Preparation method of crosslinked polymer, modified calcium carbonate particles and plugging agent Download PDFInfo
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- CN110229266B CN110229266B CN201910317917.7A CN201910317917A CN110229266B CN 110229266 B CN110229266 B CN 110229266B CN 201910317917 A CN201910317917 A CN 201910317917A CN 110229266 B CN110229266 B CN 110229266B
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
- C08F220/00—Copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and only one being terminated by only one carboxyl radical or a salt, anhydride ester, amide, imide or nitrile thereof
- C08F220/02—Monocarboxylic acids having less than ten carbon atoms; Derivatives thereof
- C08F220/04—Acids; Metal salts or ammonium salts thereof
- C08F220/06—Acrylic acid; Methacrylic acid; Metal salts or ammonium salts thereof
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- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
- C09K8/00—Compositions for drilling of boreholes or wells; Compositions for treating boreholes or wells, e.g. for completion or for remedial operations
- C09K8/42—Compositions for cementing, e.g. for cementing casings into boreholes; Compositions for plugging, e.g. for killing wells
- C09K8/426—Compositions for cementing, e.g. for cementing casings into boreholes; Compositions for plugging, e.g. for killing wells for plugging
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- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
- C09K2208/00—Aspects relating to compositions of drilling or well treatment fluids
- C09K2208/08—Fiber-containing well treatment fluids
Abstract
The invention provides a preparation method of a cross-linked polymer, modified calcium carbonate particles and a plugging agent. A process for the preparation of a crosslinked polymer comprising the steps of: 1) mixing acrylic acid, 2-acrylamide-2-methylpropanesulfonic acid and water, and adjusting the pH value to obtain a first mixed solution; 2) and adding a cross-linking agent into the first mixed solution, heating, adding an initiator, and stirring to obtain the cross-linked polymer. The modified calcium carbonate particle comprises a shell and a core material, wherein the shell is the cross-linked polymer obtained by the preparation method, and the core material is the calcium carbonate particle. The main agent in the plugging agent is modified calcium carbonate, so that the brittleness of the original calcium carbonate particles is reduced, and the pressure-bearing capacity is improved. The modified calcium carbonate particles with different particle sizes are matched with each other in particle size, and other plugging materials are used for preparing the plugging agent, so that the acid dissolution rate is up to 75%, and the temperature resistance is high. (2) The plugging agent is more convenient to use.
Description
Technical Field
The invention provides a preparation method of a cross-linked polymer and cross-linked polymer modified calcium carbonate particles prepared by the method, and particularly relates to a plugging agent containing the modified calcium carbonate particles.
Background
The reservoir has a higher porosity and permeability relative to the cap rock. The porosity directly determines the amount of hydrocarbon stored in the formation, and the permeability controls the hydrocarbon production capacity of the reservoir. The pore space of the reservoir is not only a storage space but also an important percolation channel, in the exploration and development process, the reservoir is relatively poor in cementation and rich in pores, so that leakage is easy to occur, a solid phase in drilling fluid enters a hydrocarbon reservoir to cause pore throat blockage, and a liquid phase enters the hydrocarbon reservoir to act with the rock and the fluid of the hydrocarbon reservoir to destroy the original balance of the hydrocarbon reservoir, so that potential damage factors of the hydrocarbon reservoir are induced, the permeability is reduced, and the yield of the reservoir is influenced. The carbonate reservoir is an important oil and gas reservoir, the oil and gas reserves in the carbonate reservoir account for about half of the total oil and gas reserves in the world, and the yield reaches more than 60 percent of the total yield. The fractured reservoir is the main reservoir type of the carbonate reservoir and is also an important leakage channel, and the plugging agent used for the stratum has strong plugging capability and focuses on the condition that the reservoir cannot be polluted. Therefore, the research on the carbonate reservoir fractured leakage plugging agent which is plugged and opened has important practical significance.
The existing acid-soluble plugging agent or formula mostly uses calcium carbonate particles as bridging materials, the calcium carbonate particles have low bearing capacity, so that the overall bearing capacity of the prepared plugging slurry is low, the plugging effect is influenced, most of the acid-soluble plugging agent cannot be used as the plugging formula alone, the acid solubility of the compounded plugging formula is basically about 50%, the plugging rate is not high, and the plugging agent with strong bearing capacity and high acid solubility needs to be researched and developed.
Disclosure of Invention
The invention provides a preparation method of a cross-linked polymer, which comprises the following steps:
1) mixing acrylic acid, 2-acrylamide-2-methylpropanesulfonic acid and water, and adjusting the pH value to obtain a first mixed solution;
2) and adding a cross-linking agent into the first mixed solution, heating, adding a first initiator and a second initiator, and stirring to obtain the cross-linked polymer.
In one embodiment, the acrylic acid is 30 to 45 parts, the 2-acrylamide-2-methylpropanesulfonic acid is 10 to 15 parts, the water is 100 to 120 parts, the crosslinking agent is 0.05 to 0.1 part, the first initiator is 0.15 to 0.2 part, and the second initiator is 0.15 to 0.2 part by mass.
In a particular embodiment, in step 1), the pH is between 6.8 and 7.2, for example pH 7.
In a specific embodiment, in step 2), the temperature after the temperature rise is 50 to 60 ℃.
In a particular embodiment, in step 2), the stirring time is between 20 minutes and 30 minutes.
In one embodiment, the crosslinker is N, N' -methylenebisacrylamide.
In one embodiment, the first initiator is potassium persulfate and the second initiator is sodium bisulfite.
The second aspect of the present invention provides a modified calcium carbonate particle comprising a shell and a core material, wherein the shell is the crosslinked polymer obtained by the production method according to any one of the first aspect of the present invention, and the core material is a calcium carbonate particle.
In one embodiment, the calcium carbonate particles have a particle size of 0.8 to 5mm, and the modified calcium carbonate particles having the calcium carbonate particles as a core material have a particle size of 0.8 to 5 mm.
In one embodiment, the calcium carbonate particles have a particle size of 0.8 to 1mm, and the modified calcium carbonate particles having the calcium carbonate particles as a core material have a particle size of 0.8 to 1 mm.
In one embodiment, the calcium carbonate particles have a particle size of 3 to 5mm, and the modified calcium carbonate particles having the calcium carbonate particles as a core material have a particle size of 3 to 5 mm.
In one embodiment, the calcium carbonate particles have a particle size of 3.35 to 4.75mm, and the modified calcium carbonate particles having the calcium carbonate particles as a core material have a particle size of 3.35 to 4.75 mm.
The third invention provides a plugging agent, which comprises modified calcium carbonate particles, filling particles and fibers.
In one embodiment, the modified calcium carbonate particles comprise first modified calcium carbonate particles and second modified calcium carbonate particles, wherein the first modified calcium carbonate particles have a particle size of 3 to 5mm and the second modified calcium carbonate particles have a particle size of 0.8 to 1 mm.
In one embodiment, the first modified calcium carbonate particles have a particle size of 3.35 to 4.75 mm.
In a specific embodiment, the first modified calcium carbonate particles and the second modified calcium carbonate particles are independently used in an amount of 23% to 25% based on 100% by mass of the plugging agent.
In one embodiment, the filler particles are 58 to 75 μm calcium carbonate powder, which is used in an amount of 35 to 38% based on 100% by mass of the plugging agent.
In one specific embodiment, the fibers are polyester fibers with breaking strength of more than 4 cN and sepiolite fibers with the sepiolite content of more than 60% by mass, wherein the polyester fibers account for 0.2-0.3% by mass of the plugging agent and the sepiolite fibers account for 11.7-18.8% by mass of the plugging agent.
In one embodiment, the polyester fibers have a length of 8 to 12mm (e.g., 10 nm).
In one embodiment, the fibers have a breaking strength in the range of 10 centinewtons to 35 centinewtons.
In a particular embodiment, the sepiolite fibers have a sepiolite mass content in the range of from 60% to 66%.
The invention has the beneficial effects that:
compared with the existing reservoir plugging agent, the carbonate reservoir fracture-type leakage plugging agent has the following advantages:
(1) the main agent in the plugging agent is modified calcium carbonate, and the polymer is attached to the surface of the sodium carbonate, so that the brittleness of the original calcium carbonate particles is reduced, and the bearing capacity is improved, and the plugging agent is more suitable for solving the problem of leakage of a low-pressure reservoir. The modified calcium carbonate particles with different particle sizes are matched with each other in particle size and are supplemented with other plugging materials to prepare the plugging agent, so that the acid dissolution rate is up to 75 percent, the temperature resistance is high, and the plugging agent can be directly used for plugging 5-8mm cracks.
(2) Simultaneously using two fibers, namely polyester fiber and sepiolite fiber; the polyester fiber has high strength, can wrap large particles and other materials, and can improve the compactness of a plugging layer so as to enhance the plugging capability of the plugging material; the sepiolite fibers can be uniformly dispersed in the slurry to form a fiber net structure, so that the suspension property of the plugging material in the slurry is improved, the particle size is uniformly matched, and the plugging capability is improved.
(3) The plugging agent is more convenient to use, does not need particle size matching, and can be directly added into drilling fluid during slurry preparation or prepared by using 5% bentonite slurry.
Detailed Description
The present invention is further illustrated by the following examples, which are intended to be purely exemplary of the invention and are not to be construed as limiting the invention in any way.
The materials used in the following examples are commercially available unless otherwise specified.
Example 1
Preparation of crosslinked polymer, modified calcium carbonate particles and plugging agent
Preparation of crosslinked polymers: accurately weighing 30 parts of acrylic acid and 10 parts of 2-acrylamide-2-methylpropanesulfonic acid in 100 parts of distilled water, adding 20% of sodium hydroxide solution while stirring to adjust the pH value to 7, adding 0.05 part of N, N' -methylenebisacrylamide, heating to 50 ℃, adding 0.15 part of potassium persulfate and 0.15 part of sodium bisulfite, continuously stirring for 20 minutes, and pouring into a tray to obtain the crosslinked polymer 1 #.
Preparation of first modified calcium carbonate particles: sieving out calcium carbonate particles 1-1A # with the particle size of 3.35-4.75mm by using standard sieves with the particle size of 3.35mm and 4.75mm, immediately soaking the calcium carbonate particles in the crosslinked polymer 1# in a tray, vibrating the tray for 5 minutes to uniformly wrap the calcium carbonate particles, standing for 1 minute, fishing out the calcium carbonate particles by using a screen with the particle size of 0.60mm, baking the calcium carbonate particles in an oven with the temperature of 105 ℃ for 2 hours, taking out the calcium carbonate particles, and naturally cooling the calcium carbonate particles to the room temperature to obtain the modified calcium carbonate particles 1-1B # with the particle size of 3.35-4.75 mm.
Preparation of the second modified calcium carbonate particles: sieving out 0.83-1.00mm calcium carbonate particles 1-2A # by using a standard sieve of 0.83mm and 1.00mm, immediately soaking the calcium carbonate particles in the crosslinked polymer 1# in a tray, vibrating the tray for 5 minutes to uniformly wrap the calcium carbonate particles, standing for 1 minute, fishing out the calcium carbonate particles by using a 0.60mm screen, baking the calcium carbonate particles in an oven at 105 ℃ for 2 hours, taking out the calcium carbonate particles, and naturally cooling to room temperature to obtain 0.83-1.00mm modified calcium carbonate particles 1-2B #.
Preparing a plugging agent: the plugging agent 1# is obtained by mixing the following components: stirring 23 wt% of first modified calcium carbonate particles 1-1B #, 23 wt% of second modified calcium carbonate particles 1-2B #, and 38 wt% of calcium carbonate particles with the particle size of 58-75 mu m in a mixer at 25 ℃ until the mixture is uniform, slowly adding 0.3 wt% of polyester fiber with the length of 8mm and the breaking strength of 12 cN and 15.7 wt% of sepiolite fiber (the mass content of sepiolite is 65%), and stirring until the mixture is uniform.
Example 2
Preparation of crosslinked polymer, modified calcium carbonate particles and plugging agent
Preparation of crosslinked polymers: accurately weighing 40 parts of reaction acrylic acid and 15 parts of reaction 2-acrylamide-2-methylpropanesulfonic acid in 110 parts of distilled water, adding 20% sodium hydroxide solution while stirring to adjust the pH value to 7, adding 0.08 part of N, N' -methylenebisacrylamide, heating to 55 ℃, adding 0.2 part of potassium persulfate and 0.2 part of sodium bisulfite, continuously stirring for 25 minutes, and pouring into a tray to obtain the crosslinked polymer 2 #.
Preparation of first modified calcium carbonate particles: sieving out calcium carbonate particles 2-1A # with the particle size of 3.35-4.75mm by using standard sieves with the particle size of 3.35mm and 4.75mm, immediately soaking the calcium carbonate particles in the crosslinked polymer 2# in a tray, vibrating the tray for 5 minutes to uniformly wrap the calcium carbonate particles, standing for 1 minute, fishing out the calcium carbonate particles by using a screen with the particle size of 0.60mm, baking the calcium carbonate particles in an oven with the temperature of 105 ℃ for 2 hours, taking out the calcium carbonate particles, and naturally cooling the calcium carbonate particles to room temperature to obtain modified calcium carbonate particles 2-1B # with the particle size of 3.35-4.75 mm.
Preparation of the second modified calcium carbonate particles: sieving out 0.83-1.00mm calcium carbonate particles 2-2A # by using a standard sieve of 0.83mm and 1.00mm, immediately soaking the calcium carbonate particles in the crosslinked polymer 2# in a tray, vibrating the tray for 5 minutes to uniformly wrap the calcium carbonate particles, standing for 1 minute, fishing out the calcium carbonate particles by using a 0.60mm screen, baking the calcium carbonate particles in an oven at 105 ℃ for 2 hours, taking out the calcium carbonate particles, and naturally cooling to room temperature to obtain 0.83-1.00mm modified calcium carbonate particles 2-2B #.
Preparing a plugging agent: the plugging agent 2# is obtained by mixing the following components: stirring 24 wt% of first modified calcium carbonate particles 2-1B #, 25 wt% of second modified calcium carbonate particles 2-2B #, and 36 wt% of calcium carbonate particles with the particle size of 58-75 mu m in a mixer at 20 ℃ until the mixture is uniform, slowly adding 0.2 wt% of polyester fiber with the length of 10mm and the breaking strength of 10 cN and 14.8 wt% of sepiolite fiber (the mass content of sepiolite is 60%), and stirring until the mixture is uniform.
Example 3
Preparation of crosslinked polymer, modified calcium carbonate particles and plugging agent
Preparation of crosslinked polymers: accurately weighing 45 parts of reaction acrylic acid and 15 parts of reaction 2-acrylamide-2-methylpropanesulfonic acid in 120 parts of distilled water, adding 20% of sodium hydroxide solution while stirring to adjust the pH value to 7.2, adding 0.1 part of N, N' -methylenebisacrylamide, heating to 60 ℃, adding 0.2 part of potassium persulfate and 0.15 part of sodium bisulfite, and continuously stirring for 30 minutes to obtain the crosslinked polymer No. 3.
Preparation of first modified calcium carbonate particles: sieving out 3.35-4.75mm calcium carbonate particles 3-1A # by using a standard sieve of 3.35mm and 4.75mm, immediately soaking the calcium carbonate particles in the crosslinked polymer 3# in a tray, vibrating the tray for 5 minutes to uniformly wrap the calcium carbonate particles, standing for 1 minute, fishing out the calcium carbonate particles by using a 0.60mm sieve, baking the calcium carbonate particles in an oven at 105 ℃ for 2 hours, taking out the calcium carbonate particles, and naturally cooling to room temperature to obtain 3.35-4.75mm modified calcium carbonate particles 3-1B #.
Preparation of the second modified calcium carbonate particles: sieving out 0.83-1.00mm calcium carbonate particles 3-2A # by using a standard sieve of 0.83mm and 1.00mm, immediately soaking the calcium carbonate particles in the crosslinked polymer 3# in a tray, vibrating the tray for 5 minutes to uniformly wrap the calcium carbonate particles, standing for 1 minute, fishing out the calcium carbonate particles by using a 0.60mm screen, baking the calcium carbonate particles in an oven at 105 ℃ for 2 hours, taking out the calcium carbonate particles, and naturally cooling to room temperature to obtain 0.83-1.00mm modified calcium carbonate particles 3-2B #.
Preparing a plugging agent: the plugging agent 3# is obtained by mixing the following components: stirring 23 wt% of first modified calcium carbonate particles 3-1B #, 25 wt% of second modified calcium carbonate particles 3-2B #, and 38 wt% of calcium carbonate particles with the particle size of 58-75 mu m in a mixer at 30 ℃ until the mixture is uniform, slowly adding 0.2 wt% of polyester fiber with the length of 12mm and the breaking strength of 29 cN and 13.8 wt% of sepiolite fiber (the mass content of sepiolite is 62.5%), and stirring until the mixture is uniform.
Example 4
Preparation of crosslinked polymer, modified calcium carbonate particles and plugging agent
Preparation of crosslinked polymers: accurately weighing 38 parts of reaction acrylic acid and 12 parts of reaction 2-acrylamide-2-methylpropanesulfonic acid in 120 parts of distilled water, adding 20% of sodium hydroxide solution while stirring to adjust the pH value to 7, adding 0.1 part of N, N' -methylenebisacrylamide, heating to 58 ℃, adding 0.2 part of potassium persulfate and 0.15 part of sodium bisulfite, and continuously stirring for 30 minutes to obtain the crosslinked polymer No. 4.
Preparation of first modified calcium carbonate particles: sieving out calcium carbonate particles 4-1A # with the particle size of 3.35-4.75mm by using standard sieves with the particle size of 3.35mm and 4.75mm, immediately soaking the calcium carbonate particles 4-1A # in a cross-linked polymer 4# in a tray, vibrating the tray for 5 minutes to uniformly wrap the calcium carbonate particles, standing for 1 minute, fishing out the calcium carbonate particles by using a screen with the particle size of 0.60mm, baking the calcium carbonate particles in an oven with the temperature of 105 ℃ for 2 hours, taking out the calcium carbonate particles, and naturally cooling to room temperature to obtain modified calcium carbonate particles 4-1B # with the particle size of 3.35-4.75 mm.
Preparation of the second modified calcium carbonate particles: sieving out 0.83-1.00mm calcium carbonate particles 4-2A # by using a standard sieve of 0.83mm and 1.00mm, immediately soaking the calcium carbonate particles in the crosslinked polymer 4# in a tray, vibrating the tray for 5 minutes to uniformly wrap the calcium carbonate particles, standing for 1 minute, fishing out the calcium carbonate particles by using a 0.60mm screen, baking the calcium carbonate particles in an oven at 105 ℃ for 2 hours, taking out the calcium carbonate particles, and naturally cooling to room temperature to obtain 0.83-1.00mm modified calcium carbonate particles 4-2B #.
Preparing a plugging agent: the plugging agent 4# is obtained by mixing the following components: stirring 23 wt% of first modified calcium carbonate particles 4-1B #, 23 wt% of second modified calcium carbonate particles 4-2B #, and 35 wt% of calcium carbonate particles with the particle size of 58-75 mu m in a mixer at 25 ℃ until the mixture is uniform, slowly adding 0.2 wt% of polyester fiber with the length of 10mm and the breaking strength of 35 cN and 18.8 wt% of sepiolite fiber (the mass content of sepiolite is 65%), and stirring until the mixture is uniform.
Example 5
Preparation of crosslinked polymer, modified calcium carbonate particles and plugging agent
Preparation of crosslinked polymers: accurately weighing 38 parts of reaction acrylic acid and 12 parts of reaction 2-acrylamide-2-methylpropanesulfonic acid in 120 parts of distilled water, adding 20% of sodium hydroxide solution while stirring to adjust the pH value to 6.8, adding 0.1 part of N, N' -methylenebisacrylamide, heating to 60 ℃, adding 0.2 part of potassium persulfate and 0.15 part of sodium bisulfite, and continuously stirring for 28 minutes to obtain the crosslinked polymer No. 5.
Preparation of first modified calcium carbonate particles: sieving out calcium carbonate particles 5-1A # with the particle size of 3.35-4.75mm by using standard sieves with the particle size of 3.35mm and 4.75mm, immediately soaking the calcium carbonate particles in the crosslinked polymer 5# in a tray, vibrating the tray for 5 minutes to uniformly wrap the calcium carbonate particles, standing for 1 minute, fishing out the calcium carbonate particles by using a screen with the particle size of 0.60mm, baking the calcium carbonate particles in an oven with the temperature of 105 ℃ for 2 hours, taking out the calcium carbonate particles, and naturally cooling the calcium carbonate particles to the room temperature to obtain the modified calcium carbonate particles 5-1B # with the particle size of 3.35-4.75 mm.
Preparation of the second modified calcium carbonate particles: sieving out 0.83-1.00mm calcium carbonate particles 5-2A # by using a standard sieve of 0.83mm and 1.00mm, immediately soaking the calcium carbonate particles in the crosslinked polymer 5# in a tray, vibrating the tray for 5 minutes to uniformly wrap the calcium carbonate particles, standing for 1 minute, fishing out the calcium carbonate particles by using a 0.60mm screen, baking the calcium carbonate particles in an oven at 105 ℃ for 2 hours, taking out the calcium carbonate particles, naturally cooling to room temperature, and thus obtaining 0.83-1.00mm modified calcium carbonate particles 5-2B #.
Preparing a plugging agent: the plugging agent 5# is obtained by mixing the following components: stirring 25 wt% of first modified calcium carbonate particles 5-1B #, 25 wt% of second modified calcium carbonate particles 5-2B #, 38 wt% of calcium carbonate particles with the particle size of 58-75 mu m in a mixer at 25 ℃ until the calcium carbonate particles are uniform, slowly adding 0.3 wt% of polyester fiber with the length of 10mm and the breaking strength of 35 cN and 11.7 wt% of sepiolite fiber (the mass content of the sepiolite is 66%), and stirring until the calcium carbonate particles are uniform.
Example 6
Test of pressure-bearing capacity of modified calcium carbonate particles
500g of calcium carbonate particles 1-1A #, 2-1A #, 3-1A #, 1-1B #, 2-1B # and 3-1B # (in terms of mass: M1) before and after modification were respectively added to 2000mL of water and soaked for 16 hours, then the calcium carbonate particles were taken out, surface moisture was sucked off, the calcium carbonate particles were put into a pressure crusher and pressed under 3.5MPa for 5 minutes, then the calcium carbonate particles were taken out, particles (in terms of mass: M2, in terms of unit: g) between a 3.35mm standard sieve and a 4.75mm standard sieve were weighed, and the crushing rate P was calculated according to formula 1 and expressed as a percentage. The test results are shown in Table 1.
The method of calculating the breakage rate P is as follows: p ═ (M1-M2)/M1 ═ 100% (formula 1)
Table 1: three groups of modified calcium carbonate particles and test of breakage rate of modified calcium carbonate particles
From the test results it is possible to obtain: the crushing rate of the five groups of modified calcium carbonate particles is lower than that of the calcium carbonate particles before modification by about 20 percent, and the calcium carbonate particles after modification have stronger pressure-bearing capacity than that of the calcium carbonate particles before modification.
Example 7
Test of pressure bearing capacity of plugging agent
The experimental method comprises the following steps: the plugging experiment instrument is a dynamic simulation device for Hubei Jingzhou linkage, and plugging agents 1#, 2#, 3#, 4# and 5# prepared in examples 1 to 5 are respectively tested by wedge plates with different specifications as shown in Table 2, so that the maximum pressure-bearing capacity is tested. Specific values are shown in Table 2.
Table 2 test of the bearing capacity of three sets of carbonate reservoir fracture-type leakage plugging agents
Experimental data show that the carbonate reservoir fracture type leakage plugging agent can plug 5-8mm fractures, and has the pressure bearing capacity of more than 10MPa and strong pressure bearing capacity.
Example 8
Acid solubility test
The test method comprises the following steps: respectively weighing 20g of the plugging agents No. 1, No. 2 and No. 3 prepared in the embodiments 1 to 5 to be accurate to 0.1g (mass is M3, unit: g), respectively placing the plugging agents in 1000mL beakers, adding a little water to wet samples, dropwise adding 200mL of 15% hydrochloric acid, after the violent reaction stops, stirring by using a glass rod, placing the beakers in a constant temperature water bath kettle at a constant temperature of 60 ℃, continuing to react until no bubble is generated, filtering by using filter paper (mass is M4, unit: g), cleaning the beakers by using distilled water until no residue is generated, and cleaning the residue on the filter paper by using the distilled water until the filtrate is neutral. The residue and the filter paper were placed in an evaporation dish (mass: M5, unit: g), dried in a drying cabinet at 105 ℃. + -. 3 ℃ for 6h, and the mass of the residue + filter paper + evaporation dish (mass: M6, unit: g) was weighed to the nearest 0.1 g.
Calculating the acid solubility according to formula (2): s ═ 100% (formula 2) (M6-M5-M4)/M3 ═ 100%
Wherein S in the formula is the content of hydrochloric acid insoluble substances and is expressed by percentage.
The content of the hydrochloric acid insoluble substance is determined for 3 times according to the test method for the content of the hydrochloric acid insoluble substance, the difference value of the parallel test measurement results is not more than 0.5 percent, and the arithmetic mean value is taken to obtain the content of the hydrochloric acid insoluble substance. The specific test values are shown in Table 3.
Table 3 acid solubility test for five carbonate reservoir fracture-type loss plugging agents
| Examples | Acid solubility% |
| Example 1 | 78.58 |
| Example 2 | 82.05 |
| Example 3 | 80.70 |
| Example 4 | 76.20 |
| Example 5 | 78.92 |
The experimental data show that the acid dissolution rate of the carbonate reservoir fracture type leakage plugging agent is more than 75%.
While the invention has been described with reference to specific embodiments, those skilled in the art will appreciate that various changes can be made without departing from the true spirit and scope of the invention. In addition, many modifications may be made to adapt a particular situation, material, composition of matter, and method to the essential scope and spirit of the present invention. All such modifications are intended to be included within the scope of the present invention as defined in the appended claims.
Claims (13)
1. A plugging agent, which comprises modified calcium carbonate particles, filling particles and fibers;
the modified calcium carbonate particle comprises a shell and a core material, wherein the shell is a cross-linked polymer, the core material is a calcium carbonate particle, and the cross-linked polymer is prepared by the following method:
1) mixing acrylic acid, 2-acrylamide-2-methylpropanesulfonic acid and water, and adjusting the pH value to obtain a first mixed solution;
2) adding a cross-linking agent into the first mixed solution, heating, adding a first initiator and a second initiator, and stirring to obtain the cross-linked polymer; the cross-linking agent is N, N' -methylene bisacrylamide; the first initiator is potassium persulfate, and the second initiator is sodium bisulfite;
the modified calcium carbonate particles comprise first modified calcium carbonate particles and second modified calcium carbonate particles, wherein the particle size of the first modified calcium carbonate particles is 3-5 mm; the second modified calcium carbonate particles have a particle size of 0.8 to 1 mm.
2. The plugging agent according to claim 1, wherein the particle size of the calcium carbonate particles in the second modified calcium carbonate particles is 0.8 to 1mm, and the particle size of the second modified calcium carbonate particles using it as a core material is 0.8 to 1 mm;
the particle size of the calcium carbonate particles in the first modified calcium carbonate particles is 3 to 5mm, and the particle size of the first modified calcium carbonate particles taking the calcium carbonate particles as the core material is 3 to 5 mm.
3. The plugging agent according to claim 2, wherein the first modified calcium carbonate particles have a particle size of 3.35 to 4.75mm, the calcium carbonate particles have a particle size of 3.35 to 4.75mm, and the modified calcium carbonate particles using the same as a core material have a particle size of 3.35 to 4.75 mm.
4. The plugging agent according to claim 1, wherein the acrylic acid is 30 to 45 parts, the 2-acrylamido-2-methylpropanesulfonic acid is 10 to 15 parts, the water is 100 to 120 parts, the crosslinking agent is 0.05 to 0.1 part, the first initiator is 0.15 to 0.2 part, and the second initiator is 0.15 to 0.2 part by mass.
5. Lost circulation additive of claim 1 wherein in step 1) the pH is from 6.8 to 7.2.
6. Lost circulation additive according to claim 1, wherein in step 2), the temperature after temperature rise is 50 to 60 ℃.
7. Plugging agent according to claim 1, characterized in that in step 2), the stirring time is 20 to 30 minutes.
8. The plugging agent according to claim 1, wherein the first modified calcium carbonate particles and the second modified calcium carbonate particles are independently used in an amount of 23% to 25% based on 100% by mass of the plugging agent.
9. The plugging agent according to claim 1, wherein the filling particles are 58 to 75 μm calcium carbonate powder in an amount of 35 to 38% based on 100% by mass of the plugging agent.
10. The plugging agent according to claim 1, wherein the fibers are polyester fibers with breaking strength of more than 4 cN and sepiolite fibers with sepiolite mass content of more than 60%, wherein the amount of the polyester fibers is 0.2-0.3% and the amount of the sepiolite fibers is 11.7-18.8% based on 100% of the plugging agent.
11. Lost circulation additive of claim 10 wherein the polyester fibers have a length of 8 to 12 mm.
12. Lost circulation additive of claim 10 wherein the breaking strength of the fibers is in the range of 10 to 35 centinewtons.
13. Lost circulation additive of claim 10 wherein the sepiolite fibers have a sepiolite mass content in the range of 60% to 66%.
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102993370A (en) * | 2011-09-14 | 2013-03-27 | 彭仕明 | Preparation process of leak protection plugging agent along with drilling by controlling reaction temperature |
| CN104448136A (en) * | 2014-10-31 | 2015-03-25 | 中国石油化工集团公司 | Preparation method of while-drilling plugging fluid for oil-based drilling fluid |
| CN106317321A (en) * | 2015-07-06 | 2017-01-11 | 中国石油化工股份有限公司 | Composition used for preparing downhole cross-linked complex gel and cross-linked complex gel prepared thereby |
| CN107987807A (en) * | 2017-11-28 | 2018-05-04 | 中国石油集团渤海钻探工程有限公司 | Shell core formula oil base drilling fluid leak stopping bridge formation particle and preparation method thereof |
| CN108727535A (en) * | 2017-04-21 | 2018-11-02 | 中国石油化工股份有限公司 | A kind of delay water swelling sealing agent and preparation method thereof |
-
2019
- 2019-04-19 CN CN201910317917.7A patent/CN110229266B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102993370A (en) * | 2011-09-14 | 2013-03-27 | 彭仕明 | Preparation process of leak protection plugging agent along with drilling by controlling reaction temperature |
| CN104448136A (en) * | 2014-10-31 | 2015-03-25 | 中国石油化工集团公司 | Preparation method of while-drilling plugging fluid for oil-based drilling fluid |
| CN106317321A (en) * | 2015-07-06 | 2017-01-11 | 中国石油化工股份有限公司 | Composition used for preparing downhole cross-linked complex gel and cross-linked complex gel prepared thereby |
| CN108727535A (en) * | 2017-04-21 | 2018-11-02 | 中国石油化工股份有限公司 | A kind of delay water swelling sealing agent and preparation method thereof |
| CN107987807A (en) * | 2017-11-28 | 2018-05-04 | 中国石油集团渤海钻探工程有限公司 | Shell core formula oil base drilling fluid leak stopping bridge formation particle and preparation method thereof |
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