RU2705113C1 - Granular magnetic polymer and grouting mixture for cementing of casing columns based on magnetic polymer - Google Patents

Abstract

FIELD: composite materials.SUBSTANCE: invention relates to production of composite materials, in particular to production of magnetically active elastic composites (polymers), intended for production of cement mixture controlled by magnetic field, as well as to methods of fixing gas-oil-water wells during cementing of casing strings at different stages of construction and operation of well, if necessary providing extremely low values of fluid permeability of plugging material behind production string. Technical result is achieved by the fact that disclosed is a granular magnetic polymer for making composite materials in cement mixture elements, consisting of an elastic polymer matrix, a magnetic filler and a cement additive, wherein the polymer matrix used is natural and/or synthetic rubber, magnetic filler with particle size in range of 1–100 mcm is magnetic powders of iron-neodymium boron NdFeB, and/or magnetite FeO, and/or iron powder, and/or magnetic alloys of iron – iron-cobalt, and/or iron-nickel, and/or permalloy alloy, portland cement is used as cement additive at following content of components, wt h: magnetic filler 1–75, portland cement 1–75, polymer matrix – 100 and additionally carbon or basalt fibers – 0–50, to produce granules with the following characteristics: density of magnetic polymer 2–3.5 g/cm, elasticity 0.5–30 MPa, residual magnetization 1–30 Gs·cm/g with operating temperature from -50 to + 200 °C.EFFECT: technical result consists in producing a magnetic polymer and grouting mixture containing a magnetic polymer, characterized by the following characteristics: reduced cracks of the frozen solution, increased elasticity, increased adhesion with the casing string, namely improved operational properties of the cement solution consists in reduction of cracks, increase in elasticity, increasing adhesion with a casing string due to addition of a complex polymer additive in form of polymer particles into the cement solution, including magnetic particles and cement particles.4 cl, 9 dwg, 3 tbl

Description

The invention relates to the field of creating composite materials, in particular, to the production of magnetically active elastic composites (polymers) intended for the manufacture of magnetic field-controlled elements of a cement mixture, as well as to methods for attaching gas-oil-water production wells when cementing casing strings at different stages of construction and well operation, if necessary, ensuring extremely low fluid permeability values of the plugging material behind the production string.

From RU 2316073 C1, publ. 01/27/2008 and RU 2226012 C1, publ. 03/20/2004 known magnetic polymers, which are a composition of magnetic fillers in a polymer binder.

From RU 2286374 C2, publ. October 27, 2007, an invention is known that relates to the field of exploratory drilling and can be used in the production of cementing conductors and technical columns in oil and gas wells. The composition of the cement slurry mixture for cementing columns in boreholes, containing caustic magnesite, double superphosphate, starch reagent, sodium tripolyphosphate and water, as a cementing base it contains sludge from magnesium production in the following ratio of components, mass. shares: the specified waste product of magnesium production 1.0, caustic magnesite 0.14-0.76, double superphosphate 0.2, starch reagent 0.007, sodium tripolyphosphate 0.06, water 0.6-1.0.

US 8,424,598 B2, publ. 04/23/2013 describes a method for monitoring underground flows in wells, through the use of intelligent material containing magnetically sensitive components.

The most complete overview of such magnetoelastos is presented in the book by Alekseev AG, Kornev A.E. Magnetic elastomers. - M .: Chemistry, 1987.240 s.

These materials are used to create permanent magnets and as magnetodielectrics in electronics.

A disadvantage of the known solutions is the lack of ability to interact with the cement matrix with the formation of a strong bond, and to increase the strength and elastic properties of concrete.

The objective of the invention is to create an effective controlled composition for filling the annulus of a well with a directed cementing process, which provides a controlled grouting system and flexible cement stone from a standard grouting mortar with high adhesive ability and low permeability.

The technical result of the invention is to obtain a magnetic polymer and cement slurry containing a magnetic polymer, characterized by the following characteristics: reducing cracks in the hardened mortar, increasing elasticity, increasing adhesion to the casing string, namely, improving the operational properties of the cement mortar consists in reducing cracks, increasing elasticity, increased adhesion to the casing due to the addition of a complex polymer additive in the form of polymer particles to the cement mortar constituents in the structure of magnetic particles and the cement particles.

The technical result is achieved by the fact that a granular magnetic polymer (MAP) is proposed for creating composite materials in the elements of a cement mixture consisting of an elastic polymer matrix, a magnetic filler and a cement additive, while natural and / or synthetic rubber is used as the polymer matrix, as magnetic filler with a particle size in the range of 1-100 μm using magnetic powders iron-neodymium-boron NdFeB and / or magnetite Fe ₃ O ₄ and / or powder iron and / or magnetic alloys of iron - yellow eso-cobalt and / or iron-nickel and / or permalloy alloy, as a cement additive Portland cement in the following components, wt. including: magnetic filler 1-75, Portland cement 1-75, polymer matrix - 100 and additionally carbon or basalt fibers - 0-50 to obtain granules with the following characteristics - magnetic polymer density of 2-3.5 g / cm ³ , elasticity 0 , 5-30 MPa, residual magnetization 1-30 G.s. cm ³ / g with a working temperature of -50 to + 200 ° C.

Another aspect of the invention is a grouting mixture for cementing casing strings based on a magnetic polymer, containing, by weight. including: Portland cement 100, magnetic polymer 1-50, fresh water 45, functional additives 0-50, while the magnetic polymer is a granular polymer with the following characteristics - the density of the magnetic polymer is 2-3.5 g / cm ³ , elasticity 0, 5-30 MPa, residual magnetization 1-30 G.s. cm ³ / g with a working temperature of -50 to + 200 ° C based on an elastic polymer matrix of natural and / or synthetic rubber, selected from a number of synthetic rubber contains styrene-butadiene, butyl rubber , silicone, vinyl chloride, butylac yl, polyurethane rubber, copolymers of these rubbers with Portland cement additive, and a magnetic filler of a magnetic powder with a particle size of 1-100 microns such as iron-boron-neodymium NdFeB and / or magnetite Fe ₃ O4 and / or iron powder and / or magnetic alloys of iron - iron-cobalt and / or iron-nickel and / or permalloy alloy, in the following components, wt. including: magnetic filler 5-40, Portland cement 1-50, polymer matrix 100, and additionally carbon or basalt fibers 0-50.

In addition, the invention discloses a magnetic polymer in which the polymer matrix as synthetic rubber contains styrene butadiene, butyl rubber, silicone, chlorovinyl, butyl acrylic, polyurethane rubber, copolymers of these rubbers.

It also describes a grouting mixture containing, as functional additives, reinforcing additives, accelerators, moderators, weighting agents, lightening additives, gas generating additives, water loss reducers, dispersants, sedimentation improvement additives, antifoam agents, foaming agents, thixotropic additives and their combinations in the form traditionally used for these purposes substances, such as, for example, crystalline silicon dioxide, amorphous silicon dioxide, hydrating clays, calcined or vitrified slate, slag, zelgur, metakaolin, rice hull ash, natural pozzolana, zeolite, cement kiln dust, lime, salts and resins, latex, combinations thereof and the like in the form of fibers, spheres, and hollow spheres, particles, pellets, toroids.

The technical result of the invention is as follows:

1) elastic materials and products - materials and products with elastic properties capable of restoring their original shape after unloading.

2) elasticity is the property of solid materials to return to their original shape upon elastic deformation. Solid objects will deform after the force exerted on them. If you remove the force, then the elastic material will restore its original shape and size.

3) in engineering, the elasticity of materials is measured by three types of material parameters:

- The first main parameter, “Elastic Modulus (Young's Modulus),” shows the mechanical stress (amount of force per unit area) that must be applied to achieve a certain level of deformation. The modulus is measured in Pascals (Pa) or pounds of force per square meter. inch (psi or lbf / in2). A high modulus usually indicates that the material is harder to deform.

Poisson's ratio is the ratio of relative transverse compression to relative longitudinal tension. This coefficient does not depend on the size of the body, but on the nature of the material from which the sample is made. The Poisson's ratio and Young's modulus fully characterize the elastic properties of an isotropic material and are most often indicated together. It is dimensionless, but can be specified in relative units: mm / mm, m / m.

“The elastic limit (Ultimate stress) is the maximum stress after which the material no longer behaves as elastic, and plastic (irreversible) deformation of the material will take place. After stress relief, the material will retain some permanent deformation (it can be indicated together or instead of the Poisson's ratio).

4) Rubber, as a rule, shows great elasticity. Due to its low tensile strength, it is usually highly tensile because it has a low modulus of elasticity, much lower than metals and concrete in daily use. If you take two rubber materials, one with a lower modulus will seem more elastic.

Based on these theses, it follows that the main objective of the invention is to increase the elasticity of cement cement by reducing the elastic modulus (Young's Modulus) as the main parameter. Thus, the technical result is determined by the characteristic of the elastic modulus and Poisson's ratio and / or Ultimate stress, thereby showing the elasticity of the properties. The data in the table according to patent US 20110028593 A1 characterize elastic cement according to the following criteria: filler concentration, compressive strength for 4 days, Young's modulus, Poisson's ratio (The ultimate stress is not indicated, since the ultimate strength is indicated). The table shows that the elasticity result is compared with a cement sample at a concentration of 0% filler and a decrease in modulus with an increase in rubber concentration is recorded, thereby proving that the cement has become more elastic.

Also according to the results on the graphs of sample No. 1 - 0% MAP filler (control sample), and sample No. 2 - 5% MAP filler, it is seen that when superimposed on each other, that green line (change in deformation during loading) of sample No. 2 with 5% of the filler passes lower than in the case of sample No. 1, and the tangent of the angle is correspondingly smaller, which also graphically confirms the decrease in Young's modulus, i.e. increased elasticity (Figures 2 and 3).

According to the previous paragraph, “in the case of a non-filler MAP, 0% has a higher modulus compared to the polymer, thereby demonstrating a more rigid structure, more fragile, which demonstrates the results of impact tests”.

- Fragility - the property of a material to collapse under the influence of mechanical forces suddenly (impact), without a significant change in shape.

Brittle materials poorly resist impact and shock loads. Therefore, they cannot be used where there may be shock loads, in our case it is advisable to use elastic cement in the perforation zone, since perforation creates a shock.

An example of a brittle material is glass or cast iron, whose Young's modulus is much higher than the Young's modulus of concrete or elastic cement.

In the case of checking the images for shock loading on a special bench, the test is as follows: the hammer is dropped on a cylindrical sample and the resistance of the sample to crack formation is evaluated.

The article “Bench tests of well support models” during perforation by cumulative perforators, designed by the authors of the patent of the analogue RU 2471962 with the addition of rubber in foam cement, also demonstrates this dependence of the properties of elasticity on resistance to shock loads.

The technical result of the invention also consists in the following: since the filler in the cement mixture combines an elastic polymer matrix and a magnetic filler, this magnetic filler during magnetization has additional strength due to the physical field, which is fixed and reflected in table 2 for our samples, this the force will be added to the initial chemical adhesion of the cement mixture, thereby increasing the final value of the contact force of the cement mixture with the casing.

Description of figures.

Figure 1. Portland cement particles located in the surface of spherical or flat particles of a magnetic polymer provide a strong chemical bond of the particles of the magnetic polymer with the cement stone.

Figure 2 and Figure 3. Graphs of increasing elasticity, according to a decrease in Young's modulus for samples No. 1 and No. 2.

Figure 4 and Figure 5. It is shown that the control sample completely cracked upon impact.

Figure 6. A sample of cement 5% before impact (var. 1.)

Figure 7. A sample of cement 5% after impact (var. 1.)

Figure 8. A sample of cement 5% before impact (var. 2.)

Figure 9. A sample of cement 5% after impact (var. 2.).

Grouting mortar for cementing casing strings, includes Portland cement, magnetic polymer, mixing fluid - fresh water.

Other additives suitable for use in the cementing operation may also be added to the cement preparation options.

Examples of such additives include, but are not limited to, reinforcing additives, accelerators, retarders, weighting agents, lightening agents, gas generating additives, fluid loss reducers, dispersants, additives for improving sedimentation stability, defoamers, foaming agents, thixotropic additives, and combinations thereof in the form a variety of substances traditionally used for these purposes, such as, for example, crystalline silicon dioxide, amorphous silicon dioxide, hydrating clays, calcined or vitrified th shale slag, diatomaceous earth, metakaolin, rice hull ash, natural pozzolana, zeolite, cement kiln dust, lime, salts and resins, latex, combinations thereof and the like in the form of fibers, microspheres, and others.

The cement bound to the polymer and partially extending to the surface of the elastomer provides a strong structural bond between the polymer and the total cement mass. A magnetic filler located in the bulk or on the surface of the polymer improves the bond of the composition to the metal casing.

Examples.

Getting a magnetic polymer.

To prepare a magnetically active polymer, cement, a magnetically active component and a polymer are mixed in a mixer. After the mixer, the mixture is fed into the extruder, where the mixture is fused with a polymer additive and is issued in the form of granules or in the form of a tape that is cut into cubes. In the second stage, granules or cubes are mixed with excess cement, for example, in a ratio of 1: 5 by weight and fed to the hot rollers with a screw, where spherical granules turn into plates with cement particles melted to the surface. The mixture is then dispersed on sieves with a mesh of 0.5 mm to remove excess cement.

To cement or magnetic filler in the first stage can be added: thinly cut or scraps of carbon or basalt fibers, which will allow to strengthen additionally the polymer matrix.

The content of the components of the mixture are presented in Table 1.

Example 1

A magnetic polymer is obtained by mixing Portland cement, a polymer and a magnetic filler, in which natural rubber is used as the polymer matrix, and NdFeB iron-neodymium boron magnetic powder is used as the magnetic filler, see Example 1 of the Table.

Example 2

A magnetic polymer is obtained in which natural rubber and butyl rubber are used as the polymer matrix, and magnetite is used as the magnetic filler, see Example 2 of the Table.

Example 3

A magnetic polymer is obtained in which silicone rubber is used as the polymer matrix, and powdered iron is used as the magnetic filler, see Example 3 of the Table.

Example 4

A magnetic polymer is obtained in which chlorovinyl rubber is used as the polymer matrix, and a magnetic alloy of iron-cobalt and iron is used as the magnetic filler, see Example 4 of the Table.

Example 5

A magnetic polymer is obtained in which butyl acrylic rubber is used as the polymer matrix, and the iron-nickel magnetic alloy is used as the magnetic filler, see Example 5 of the Table

Example 6

A magnetic polymer is obtained in which polyurethane rubber is used as the polymer matrix, and a permalloy alloy is used as the magnetic filler. Example 6

Also in other, non-limiting examples, styrene-butadiene rubber and copolymers of the above rubbers can be used as the polymer matrix.

The magnetic fillers used in Examples 1-6 have a particle size of 1-100 microns.

All granules obtained in Examples 1-6 are characterized by the following parameters - the density of the magnetic polymer is 2-3.5 g / cm ³ , the elasticity is 0.5-30 MPa, the residual magnetization is 1-30 G / cm ³ / g with a working temperature of -50 up to + 200 ° С magnetic polymers demonstrate the following characteristics: the density of the magnetic polymer is 2 - 3.5 g / cm ³ , the elasticity is 0.5-30 MPa, the residual magnetization is 1-30 G / cm ³ / g with a working temperature of -50 up to + 200 ° С.

Examples 7-11 show the technology by adding fibers to obtain the same final polymer characteristics.

Examples of the cement mixture.

In the preparation of the grouting mixture, the polymers obtained in Examples 1-6 are used as the magnetic polymer.

The grouting mixture may further include additives, for example, crystalline silicon dioxide, amorphous silicon dioxide, salts, fibers, hydrating clays, calcined slate, vitrified slate, microspheres, fly ash, slag, kieselguhr, metakaolin, rice husk ash, natural pozzolan, zeolite cement dust, lime, resins, latex, combinations thereof and the like.

Example (grouting):

For the preparation of cement slurry as a sample No. 1, designed for reservoir temperature of 60 ° C and containing 50 wt. including Portland cement PCT-I-G GOST 1581-96, add May 45, including fresh water, a plasticizer of 0.1 wt. hours, retarder setting cement mortar 0.1 wt. h, a sedimentation additive of 0.2 wt. hours, lower fluid loss 0.6 wt. hours, and then stirred until a homogeneous system.

For the preparation of structure-forming solution as sample No. 2, designed for reservoir temperature of 60 ° C and containing 50 wt. including Portland cement PCT-I-G GOST 1581-96, add 5 wt. h magnetically polymer (polymer) add 45 wt. h of fresh water, a plasticizer of 0.1 wt. h retarder setting of cement mortar 0.1 wt. h, sedimentation additive 0.2 may h, the loss of water loss of 0.6 wt. h and then stirred until a homogeneous system is formed.

To prepare a structure-forming solution as sample No. 3, designed for reservoir temperature of 60 ° C and containing 100 May portland cement PCT-I-G GOST 1581-96, add 8 wt. h magnetically polymer (polymer) add 45 wt. h of fresh water, a plasticizer of 0.1 wt. h retarder setting of cement mortar 0.1 wt. h, a sedimentation additive of 0.2 wt. h, a loss of fluid loss of 0.6 wt. h and then stirred until a homogeneous system is formed.

Other examples describing the production of cement mixture contain the following component composition in wt. including: Portland cement - 100, magnetic polymer from 1 to 50, fresh water - 45, and also, functional additives in the form of reinforcing additives, accelerators, moderators, weighting agents, lightening additives, gas-generating additives, fluid loss reducing agents, dispersants, can be added. additives that improve sedimentation properties, antifoam agents, foaming agents, thixotropic additives and their combinations in the form of substances traditionally used for these purposes, such as, for example, crystalline silicon dioxide, amorphous silicon dioxide hydrated clays, burnt or vitrified slate, slag, kieselguhr, metakaolin, rice husk ash, natural pozzolan, zeolite, cement dust, lime, salts and resins, latex, their combinations and the like in the form of fibers, microspheres, particles - from 0 up to 50.

The properties of the resulting cement mixture (samples 1-3) and stone from it are shown in Tables 2 and 3.

Claims (18)

1. Granular magnetic polymer to create composite materials in the elements of the cement mixture, consisting of an elastic polymer matrix, a magnetic filler and a cement additive, while natural and / or synthetic rubber is used as a polymer matrix, as a magnetic filler with a particle size in the range of 1 -100 μm use magnetic powders, iron-neodymium-boron NdFeB, and / or magnetite Fe ₃ O ₄ , and / or powdered iron, and / or magnetic alloys of iron - iron-cobalt, and / or iron-nickel, and / or permalloy spl AB, as a cement additive - Portland cement with the following content of components, wt. hours: magnetic filler 1-75, Portland cement 1-75, polymer matrix 100 and optionally carbon or basalt fibers 0-50, to obtain granules with the following characteristics: the density of the magnetic polymer is 2-3.5 g / cm ³ , the elasticity is 0.5-30 MPa, the residual magnetization is 1-30 G.s. ³ / g with a working temperature of -50 to + 200 ° C . 2. The magnetic polymer according to claim 1, characterized in that the polymer matrix as a synthetic rubber contains styrene butadiene, butyl rubber, silicone, chlorovinyl, butyl acrylic, polyurethane rubber, copolymers of these rubbers. 3. Grouting mixture for cementing casing strings based on a magnetic polymer, containing, by weight. hours: Portland cement 100, magnetic polymer 1-50, fresh water 45, functional additives 0-50, the magnetic polymer is a granular polymer with the following characteristics: the density of the magnetic polymer is 2-3.5 g / cm ³ , the elasticity is 0.5-30 MPa, the residual magnetization is 1-30 G · cm ³ / g with a working temperature of -50 up to + 200 ° С based on an elastic polymer matrix made of natural and / or synthetic rubber selected from the range styrene-butadiene, butyl rubber, silicone, chlorovinyl, butyl acrylic, polyurethane rubber, copolymers of these rubbers with the addition of Portland cement and a magnetic filler in the form of a magnetic powder with a particle size of 1-100 microns, such as iron-neodymium-boron NdFeB, and / or magnetite Fe ₃ O ₄ and / or iron powder and / or magnetic alloys of iron - iron, cobalt and / or iron-nickel , and / or permalloy alloy, in the following components, wt. hours: magnetic filler 5-40, Portland cement 1-50, polymer matrix 100 and optionally carbon or basalt fibers 0-50. 4. The grouting mixture according to claim 3, containing as functional additives reinforcing additives, accelerators, moderators, weighting agents, lightening additives, gas-generating additives, water loss reducers, dispersants, sedimentation improvement additives, defoamers, foaming agents, thixotropic additives and their combinations in the form substances traditionally used for these purposes, such as, for example, crystalline silicon dioxide, amorphous silicon dioxide, hydrating clays, calcined or vitrified slate, slag, kieselguhr , metakaolin, rice husk ash, natural pozzolan, zeolite, cement dust, lime, salts and resins, latex and their combinations, in the form of fibers, microspheres, particles.

Images