CN115572092A - Composite hollow lightening agent for well cementation and preparation method thereof - Google Patents
Composite hollow lightening agent for well cementation and preparation method thereof Download PDFInfo
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- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B40/00—Processes, in general, for influencing or modifying the properties of mortars, concrete or artificial stone compositions, e.g. their setting or hardening ability
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- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B20/00—Use of materials as fillers for mortars, concrete or artificial stone according to more than one of groups C04B14/00 - C04B18/00 and characterised by shape or grain distribution; Treatment of materials according to more than one of the groups C04B14/00 - C04B18/00 specially adapted to enhance their filling properties in mortars, concrete or artificial stone; Expanding or defibrillating materials
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Abstract
The application relates to the technical field of oil and gas field well drilling and cementing, and particularly discloses a composite hollow lightening admixture for well cementing and a preparation method thereof. The raw materials of the composite hollow weight reducer for well cementation comprise modified silicon nitride hollow microspheres, fly ash, micro silicon powder, a stabilizer, a drag reducer and a fluid loss agent. The hollow lightening admixture for the composite well cementation can be used for meeting the well cementation construction requirement of a deep well with the bottom hole pressure of more than 40Mpa, and has the advantage of improving the compressive strength and compactness of well cementation slurry.
Description
Technical Field
The application relates to the field of oil and gas field well drilling and cementing technology, in particular to a composite hollow lightening admixture for well cementation and a preparation method thereof.
Background
The oil-gas fields in China are of various types, including low-pressure permeable oil-gas fields, thick oil-gas fields, crack-shaped oil-gas fields and the like, most of the oil-gas fields have low oil layer pressure coefficient, some oil-gas fields have low original pressure, and some oil-gas fields can leak during drilling because of pressure reduction of oil wells opened for a long time, and sometimes well cementation and leakage are caused because of longer sealing, so that the oil-gas layers and the wells need to be well fixed, different well cementation methods must be adopted aiming at different oil-gas reservoir characteristics to meet the requirement, special well cementation methods such as low-density cement well cementation, graded injection well cementation and the like sometimes need to be adopted, so that special cement paste must be adopted in well cementation, and the addition of a low-density lightening admixture in the cement paste is one of the methods.
The well cementation lightening admixture is a main admixture applied to the well cementation technology of low-density cement slurry of an oil well, and directly influences the technical indexes of the density, the compressive strength and the like of the cement slurry in the oil well. The high-quality cementing and lightening agent can stabilize a cement slurry system, has good rheological property, high compressive strength, low water loss and low free liquid, does not shrink in volume after being condensed into cement stone, has a compact structure and low permeability, and has certain anti-channeling capacity.
In the related technology, for example, the application document of 200910310954.1 discloses a high-temperature low-density cement and the application thereof, the used lightening admixture is single or combined of fly ash, micro-beads, diatomite and bentonite, and the cement paste prepared by adopting the lightening admixture has the advantages of high temperature resistance, low density and high strength, so that the cement paste has good well cementation construction performance.
Aiming at the related technologies, the inventor thinks that the compressive strength of the microbeads in the related technologies is not good and cannot bear the pressure of more than 20Mpa, and in the hardening process of the well cementation cement paste, alkaline substances are generated by the hydration of cement, the concentration of the alkaline substances in the well cementation cement paste is increased along with the hardening of the well cementation cement paste, and the microbeads are easily corroded by the high-concentration alkaline substances, so that the microbeads are cracked or seeped, the compressive strength of the microbeads is greatly reduced, and the compressive strength of the well cementation paste cannot meet the requirements of deep well cementing.
Disclosure of Invention
In order to improve the compressive strength of the well cementation slurry, the application provides a composite hollow lightening admixture for well cementation and a preparation method thereof.
In a first aspect, the application provides a composite hollow lightening agent for well cementation, which adopts the following technical scheme:
the composite hollow lightening agent for well cementation is characterized by comprising the following raw materials in parts by weight: 50-60 parts of modified silicon nitride hollow microspheres, 15-25 parts of fly ash, 10-20 parts of micro silicon powder, 2-4 parts of stabilizing agent, 2-5 parts of drag reducer and 1-3 parts of fluid loss agent.
By adopting the technical scheme, the lightening admixture takes the modified silicon nitride hollow microspheres as a main body, the modified silicon nitride hollow microspheres have better strength and corrosion resistance, and can meet the well cementation construction requirement that the bottom hole pressure is more than 40 pa.
Optionally, the modified silicon nitride hollow microsphere comprises the following components in percentage by weight: 40-50% of modified silicon nitride micro powder and 50-60% of phosphate;
the modified silicon nitride micro powder is obtained by coating a hydrophobic film on the surface of the silicon nitride micro powder.
By adopting the technical scheme, the silicon nitride micro powder has better strength and hardness, the strength requirement of deep well cementing slurry on the modified silicon nitride hollow microsphere can be met, the hydrophobic film is coated on the surface of the silicon nitride micro powder, finally, a hydrophobic layer is formed on the surface of the modified silicon nitride hollow microsphere, and the hydrophobic layer blocks alkaline substances generated in the cementing slurry, so that the modified silicon nitride hollow microsphere is prevented from being corroded by the alkaline substances, the modified silicon nitride hollow microsphere can keep better corrosion resistance, the silicon nitride hollow microsphere is favorable for keeping better strength for a long time under the alkaline environment of the cementing slurry, and the well cementing construction performance of the cement slurry is further favorably improved.
Optionally, the hydrophobic film is an aluminum oxide film, and the aluminum oxide film is made of hydrophobic aluminum oxide micro powder.
By adopting the technical scheme, the hydrophobic alumina micro powder has good dispersibility, so that the electrostatic adsorption ball coating phenomenon formed in the flowing process of the hydrophobic alumina micro powder can be effectively reduced, the hydrophobic alumina micro powder is uniformly distributed on the surface of the silicon nitride micro powder, and meanwhile, the alumina film has good hydrophobicity, so that alkaline substances are prevented from permeating into the silicon nitride microspheres, and the corrosion resistance of the modified silicon nitride hollow microspheres is effectively enhanced.
Optionally, the modified silicon nitride hollow microsphere is prepared by a method comprising the following steps:
s1: pretreating silicon nitride micro powder; preparing hydrophobic alumina micro powder;
s2: soaking the pretreated silicon nitride micro powder and the hydrophobic alumina micro powder in a saturated lithium sulfate solution for 5-6h, slowly heating to 70-80 ℃ in the soaking process, keeping for 1-2h, drying to obtain modified silicon nitride micro powder, and then uniformly mixing the modified silicon nitride micro powder and phosphate at the temperature of 70-80 ℃ to obtain a liquid mixture, wherein the mass ratio of the silicon nitride micro powder to the hydrophobic alumina micro powder is 1:1;
s3: and granulating and sintering the liquid mixture to obtain the modified silicon nitride hollow microspheres.
By adopting the technical scheme, after the silicon nitride micro powder is pretreated, the hydrophobic aluminum oxide micro powder is easier to coat on the silicon nitride micro powder, the pretreated silicon nitride micro powder and the hydrophobic aluminum oxide micro powder are soaked in a saturated lithium sulfate solution, the saturated lithium sulfate solution is reduced in solubility due to the temperature rise along with the temperature rise, so that a lithium sulfate crystal with a stable structure can be separated out, the separated lithium sulfate crystal is attached to the silicon nitride micro powder and grows by taking the silicon nitride micro powder as an attachment point, the hydrophobic aluminum oxide micro powder dispersed on the surface of the silicon nitride micro powder can be bonded with the silicon nitride micro powder along with the growth of the lithium sulfate crystal, a stable monoclinic crystal bonding structure can be formed between the silicon nitride micro powder and the hydrophobic aluminum oxide micro powder through the lithium sulfate crystal, a stable aluminum oxide film is formed on the surface of the silicon nitride micro powder, and finally a hydrophobic layer is formed on the surface of the modified silicon nitride hollow microsphere, so that the corrosion resistance of the modified silicon nitride hollow microsphere is enhanced.
Optionally, the hydrophobic alumina micro powder in S1 is prepared by the following steps:
dispersing alumina micro powder in a beta-alanine solution with the mass concentration of 30-35%, then adding a trifluorobromoethane solution with the mass concentration of 0.2-0.025%, reacting for 10-12h at 25 ℃, washing the obtained product with distilled water for multiple times, and drying to obtain hydrophobic alumina micro powder; wherein the mass ratio of the alumina micro powder to the trifluorobromochloroethane solution is 1: (0.02-0.5).
By adopting the technical scheme, after the alumina micro powder is added into the beta-alanine solution, the stable Al2O3/PD composite core-shell structure is formed after stirring reaction, and as the beta-alanine on the surface of the alumina micro powder contains rich amino groups, the fluorine-containing substances with low surface energy can be more stably modified on the alumina micro powder, so that the hydrophobic alumina micro powder with better hydrophobicity is formed.
Optionally, the pretreatment of the silicon nitride micro powder in S1 includes the following steps:
dispersing silicon nitride micro powder in hydrofluoric acid solution, soaking for 0.5-1h, repeatedly washing with distilled water until the pH of the washing water is 7 +/-0.5, and drying the silicon nitride micro powder.
By adopting the technical scheme, the silicon nitride micro powder is pretreated by hydrofluoric acid solution in advance, so that the roughness of the surface of the silicon nitride can be improved, the subsequent modification operation of the silicon nitride micro powder is facilitated, and the hydrophobic alumina micro powder is more stably attached to the surface of the silicon nitride.
Optionally, the phosphate is at least one of potassium phosphate and sodium phosphate.
By adopting the technical scheme, the phosphate is beneficial to keeping better fluidity and dispersibility of the liquid mixture, and further is beneficial to forming the modified silicon nitride microspheres with uniform size and uniform wall thickness in the granulation process, and further is beneficial to improving the compressive strength of the modified silicon nitride microspheres.
In a second aspect, the application provides a preparation method of a composite hollow lightening admixture for well cementation, which adopts the following technical scheme:
a preparation method of a composite hollow lightening admixture for well cementation is characterized in that modified silicon nitride hollow microspheres, fly ash, micro silicon powder, a stabilizer, a drag reducer and a fluid loss agent are mixed according to a proportion and are uniformly stirred to obtain the composite hollow lightening admixture for well cementation.
By adopting the technical scheme, the preparation method is simple, rapid and easy to operate, the prepared lightening admixture can effectively improve the compression strength and the rheological property of the well cementation slurry in the well cementation slurry, and the modified silicon nitride hollow microspheres in the lightening admixture have higher strength and corrosion resistance, can meet the well cementation construction requirement that the bottom hole pressure is more than 40Mpa, and effectively improve the well cementation construction property of the cement slurry.
In summary, the present application has the following beneficial effects:
1. because the modified silicon nitride hollow microspheres are used as the main body of the lightening admixture, the modified silicon nitride hollow microspheres have better strength and can meet the well cementation construction requirement that the bottom hole pressure is more than 60Mpa, a hydrophobic film is coated on the surface of the silicon nitride micro powder, a hydrophobic layer is finally formed on the surface of the modified silicon nitride hollow microspheres, and the hydrophobic layer blocks alkaline substances generated in well cementation slurry, so that the modified silicon nitride hollow microspheres are prevented from being corroded by the alkaline substances, the modified silicon nitride hollow microspheres can keep better corrosion resistance, the silicon nitride hollow microspheres can be favorable for keeping better strength for a long time in the alkaline environment of the well cementation slurry, and the well cementation construction performance of the cement slurry is further improved.
2. The hydrophobic alumina micro powder is preferably coated on the surface of the silicon nitride micro powder, and the hydrophobic alumina micro powder has good dispersibility, so that the electrostatic adsorption ball coating phenomenon of the hydrophobic alumina micro powder formed in the flowing process can be effectively reduced, the hydrophobic alumina micro powder is uniformly distributed on the surface of the silicon nitride micro powder, and meanwhile, the alumina film has good hydrophobicity, so that alkaline substances are prevented from permeating into the silicon nitride micro powder, and the corrosion resistance of the modified silicon nitride hollow micro powder is effectively enhanced.
3. The modified silicon nitride hollow microsphere can form a stable monoclinic crystal connection structure between silicon nitride micro powder and hydrophobic aluminum oxide micro powder through lithium sulfate crystals in the preparation process, so that a stable aluminum oxide film is formed on the surface of the silicon nitride micro powder, and finally a hydrophobic layer is formed on the surface of the modified silicon nitride hollow microsphere, so that the corrosion resistance of the modified silicon nitride hollow microsphere is enhanced.
Detailed Description
The present application will be described in further detail with reference to examples.
Hydrofluoric acid solution, beta-alanine solution, trifluorobromoethane solution, lithium sulfate solution, potassium phosphate solution and sodium phosphate solution in the examples of the present application are commercially available; the stabilizer is a calcium stearate stabilizer purchased from the macro and remote chemical engineering in the Jiangxi province; drag reducers were purchased from Henan Edson environmental protection technologies, inc.; the fluid loss agent was purchased from Qiankun chemical technology, inc. of Renju city.
Preparation example of modified silicon nitride hollow microspheres
Preparation example 1
A modified silicon nitride hollow microsphere is prepared by the following method:
s1: pretreating silicon nitride micro powder: dispersing 10kg of silicon nitride micro powder in 15% hydrofluoric acid solution, soaking for 1h, then repeatedly washing with distilled water until the pH value of the washing water is 7, and then drying the silicon nitride micro powder;
preparing hydrophobic alumina micro powder: dispersing 10kg of alumina micropowder into 20kg of 33% beta-alanine solution with mass concentration, then adding 0.2kg of 0.1% trifluorobromoethane solution with mass concentration, reacting for 10h at 25 ℃, washing the obtained product with distilled water for 3 times, and drying to obtain hydrophobic alumina micropowder;
s2: taking 5kg of pretreated silicon nitride micro powder and 5kg of hydrophobic alumina micro powder, soaking the silicon nitride micro powder and the hydrophobic alumina micro powder in a saturated lithium sulfate solution for 5 hours, slowly heating to 80 ℃ in the soaking process, keeping for 2 hours, and drying to obtain modified silicon nitride micro powder;
taking 5kg of modified silicon nitride micro powder and 5kg of potassium phosphate solution with the mass concentration of 45% at 80 ℃, and uniformly mixing to obtain a liquid mixture;
s3: pumping the liquid mixture into spray drying equipment for granulation, wherein the linear velocity of an atomizing disc is more than 120m/s, the inlet hot air temperature is 350 ℃, and the outlet temperature is 120 ℃, so as to obtain a microsphere precursor with the average particle size of 50 mu m; sintering the microsphere precursor at 900 ℃ to obtain the finished product of the modified silicon nitride hollow microsphere.
Preparation example 2
A modified silicon nitride hollow microsphere is prepared by the following method:
s1: pretreating silicon nitride micro powder: dispersing 10kg of silicon nitride micro powder in 15% hydrofluoric acid solution, soaking for 1h, then repeatedly washing with distilled water until the pH value of the washing water is 7, and then drying the silicon nitride micro powder;
preparing hydrophobic alumina micro powder: dispersing 10kg of alumina micropowder into 20kg of beta-alanine solution with the mass concentration of 30%, then adding 2.5kg of trifluorobromoethane solution with the mass concentration of 0.2%, reacting for 10h at 25 ℃, washing the obtained product with distilled water for 3 times, and drying to obtain hydrophobic alumina micropowder;
s2: taking 5kg of pretreated silicon nitride micro powder and 5kg of hydrophobic alumina micro powder, soaking the silicon nitride micro powder and the hydrophobic alumina micro powder in a saturated lithium sulfate solution for 5 hours, slowly heating to 70 ℃ in the soaking process, keeping for 2 hours, and drying to obtain modified silicon nitride micro powder;
taking 5kg of modified silicon nitride micro powder and 5kg of sodium phosphate solution with the mass concentration of 45% at 70 ℃, and uniformly mixing to obtain a liquid mixture;
s3: pumping the liquid mixture into spray drying equipment for granulation, wherein the linear velocity of an atomizing disc is more than 120m/s, the inlet hot air temperature is 350 ℃, and the outlet temperature is 120 ℃, so as to obtain a microsphere precursor with the average particle size of 50 mu m; sintering the microsphere precursor at 900 ℃ to obtain the finished product of the modified silicon nitride hollow microsphere.
Preparation example 3
A modified silicon nitride hollow microsphere is prepared by the following method:
s1: pretreating silicon nitride micro powder: dispersing 10kg of silicon nitride micro powder in 15% hydrofluoric acid solution, soaking for 1h, then repeatedly washing with distilled water until the pH value of the washing water is 7, and then drying the silicon nitride micro powder;
preparing hydrophobic alumina micro powder: dispersing 10kg of alumina micro powder into 20kg of beta-alanine solution with the mass concentration of 35%, then adding 2.5kg of trifluorobromoethane solution with the mass concentration of 0.025%, reacting for 12h at 25 ℃, washing the obtained product with distilled water for 3 times, and drying to obtain hydrophobic alumina micro powder;
s2: taking 5kg of pretreated silicon nitride micro powder and 5kg of hydrophobic alumina micro powder, soaking the silicon nitride micro powder and the hydrophobic alumina micro powder in a saturated lithium sulfate solution for 6 hours, slowly heating to 70 ℃ in the soaking process, keeping for 1 hour, and drying to obtain modified silicon nitride micro powder;
taking 5kg of modified silicon nitride micro powder and 5kg of sodium phosphate solution with the mass concentration of 45% at 80 ℃, and uniformly mixing to obtain a liquid mixture;
s3: pumping the liquid mixture into spray drying equipment for granulation, wherein the linear velocity of an atomizing disc is more than 120m/s, the inlet hot air temperature is 350 ℃, and the outlet temperature is 120 ℃, so as to obtain a microsphere precursor with the average particle size of 50 mu m; sintering the microsphere precursor at 900 ℃ to obtain the finished product of the modified silicon nitride hollow microsphere.
Preparation example 4
A modified silicon nitride hollow microsphere is different from the preparation example 1 in that: in the step S1, the silicon nitride fine powder is not modified.
Preparation example 5
A modified silicon nitride hollow microsphere is different from the preparation example 1 in that: in S1, equal amount of distilled water is adopted to replace beta-alanine solution, and the specific steps of S1 are as follows:
s1: pretreatment: dispersing 10kg of silicon nitride micro powder in 15% hydrofluoric acid solution, soaking for 1h, then repeatedly washing with distilled water until the pH value of the washing water is 7, and then drying the silicon nitride micro powder;
preparing hydrophobic alumina micro powder: dispersing 10kg of alumina micro powder in 20kg of distilled water, then adding 0.2kg of trifluorobromoethane solution with the mass concentration of 0.1%, reacting for 10 hours at 25 ℃, washing the obtained product with distilled water for 3 times, and drying to obtain the hydrophobic alumina micro powder.
Preparation example 6
A modified silicon nitride hollow microsphere is different from the preparation example 1 in that: and replacing the saturated lithium sulfate solution with a saturated sodium sulfate solution in the step S2.
Preparation example 7
A modified silicon nitride hollow microsphere is different from the preparation example 1 in that: in step S2, no temperature raising operation is performed.
Preparation example 8
A modified silicon nitride hollow microsphere is different from the preparation example 1 in that: and in the step S2, common alumina micro powder is adopted.
Embodiments of a composite hollow lightening agent for well cementation
Example 1
A composite hollow lightening agent for well cementation is disclosed, wherein the raw materials and the corresponding weights thereof are shown in Table 1, wherein modified silicon nitride hollow microspheres prepared in preparation example 1 are adopted; the preparation method of the composite hollow lightening admixture for well cementation comprises the following steps: the modified silicon nitride hollow microspheres, the fly ash, the micro silicon powder, the stabilizer, the drag reducer and the fluid loss agent are mixed according to the proportion shown in the table 1, and then stirred in a horizontal stirrer for 3min to obtain the composite hollow weight reducer for well cementation.
The application of the composite hollow lightening admixture for well cementation comprises the following steps: 5kg of the composite hollow lightening admixture for well cementation, 20kg of oil well cement, 40kg of machine-made sand and 8kg of water which are prepared in the embodiment are mixed and stirred uniformly to obtain the composite well cementation slurry.
Example 2
A composite hollow lightening agent for well cementation is different from the embodiment 1 in that the raw materials of the composite hollow lightening agent for well cementation and the corresponding weight are shown in the table 1, wherein modified silicon nitride hollow microspheres prepared in the preparation example 2 are adopted.
Example 3
A composite hollow lightening agent for well cementation is different from the embodiment 1 in that the raw materials of the composite hollow lightening agent for well cementation and the corresponding weight are shown in the table 1, wherein modified silicon nitride hollow microspheres prepared in the preparation example 3 are adopted.
TABLE 1 weight (kg) of each raw material of the lightening agent in examples 1 to 3
| Name of raw materials | Example 1 | Example 2 | Example 3 |
| Modified silicon nitride hollow microsphere | 50 | 55 | 60 |
| Fly ash | 15 | 20 | 25 |
| Silica fume | 10 | 15 | 20 |
| Stabilizer | 2 | 3 | 4 |
| Drag reducer | 2 | 4 | 5 |
| Fluid loss agent | 1 | 2 | 3 |
Example 4
A composite hollow lightening agent for well cementation is different from the hollow lightening agent in the embodiment 1, wherein the modified silicon nitride hollow microsphere prepared in the preparation example 4 is adopted as the modified silicon nitride hollow microsphere.
Example 5
A composite hollow lightening agent for well cementation is different from that in example 1 in that the modified silicon nitride hollow microsphere prepared in preparation example 5 is adopted.
Example 6
A composite hollow lightening agent for well cementation is different from the hollow lightening agent in the embodiment 1, wherein the modified silicon nitride hollow microsphere prepared in the preparation example 6 is adopted as the modified silicon nitride hollow microsphere.
Example 7
A composite hollow lightening agent for well cementation is different from the hollow lightening agent in the embodiment 1, wherein the modified silicon nitride hollow microsphere prepared in the preparation example 7 is adopted.
Example 8
A composite hollow lightening agent for well cementation is different from the hollow lightening agent in the embodiment 1 in that the modified silicon nitride hollow microsphere prepared in the preparation example 8 is adopted.
Comparative example
Comparative example 1
The weight-reducing agent comprises the following raw materials in parts by weight: 5kg of fly ash, 30kg of floating beads, 3kg of diatomite and 2kg of stabilizer; the preparation method of the lightening agent comprises the following steps:
and mixing the fly ash, the floating beads, the diatomite and the stabilizer according to the proportion, and stirring in a horizontal stirrer for 3min to obtain the lightening admixture.
The application of the lightening agent comprises the following steps: 5kg of lightening admixture, 20kg of oil well cement, 40kg of machine-made sand and 8kg of water are taken and mixed and stirred uniformly to obtain the composite well cementation slurry.
Comparative example 2
A lightening agent, differing from example 1 in that: the modified silicon nitride hollow microspheres are replaced by the same amount of silicon nitride microspheres.
The application of the lightening agent comprises the following steps: 5kg of lightening admixture, 20kg of oil well cement, 40kg of machine-made sand and 8kg of water are taken and mixed and stirred uniformly to obtain the composite well cementation slurry.
Performance test
Test-compressive strength test samples: the composite well cementing slurry obtained in examples 1-8 was used as test samples 1-8, and the composite well cementing slurry obtained in comparative examples 1-2 was used as control samples 1-2.
The test method comprises the following steps: the composite well cementation slurry of the test sample 1-8 and the reference sample 1-2 is prepared into a concrete test block, and the 28d compressive strength (MPa) of the concrete is detected according to the compressive strength test in GB/T50081-2002 Standard test method for mechanical properties of common concrete.
The test instrument: a compression testing machine.
The experimental results are as follows: as shown in table 2.
TABLE 2 test results of test samples 1-8 and control samples 1-2
It can be seen from the combination of examples 1-3, comparative example 1 and table 2 that the 28-day compressive strength of the prepared well cementation slurry is kept at about 45.5MPa by using the modified silicon nitride microspheres as the main body in examples 1-3, while the 28-day compressive strength of the prepared well cementation slurry is 12.3 by using the conventional lightening admixture in comparative example 1, which indicates that the well cementation slurry prepared by using the modified silicon nitride hollow microspheres has higher strength, and therefore, the well cementation slurry can meet the well cementation construction requirement that the bottom hole pressure is greater than 40 pa.
It can be seen by combining example 1, example 4 and table 2 that the 28-day compressive strength of the well cementation slurry prepared in example 4 of the present application is 41.4MPa, and compared with test sample 1, the 28-day compressive strength of test sample 4 is lost by 9.2%, because the modified silicon nitride hollow microsphere adopted in example 4 does not pretreat the silicon nitride micro powder in the preparation process, the smoothness of the silicon nitride surface is higher, and further the coupling stability of the hydrophobic alumina micro powder and the silicon nitride micro powder is not good during the subsequent modification, and further the hydrophobic film compactness on the surface of the modified silicon nitride hollow microsphere is not good, and the modified silicon nitride hollow microsphere is easy to be subjected to water seepage and fracture in the construction process, so that the compressive strength of the well cementation slurry is reduced.
It can be seen from the combination of example 1, example 5 and table 2 that the 28-day compressive strength of the well cementation slurry prepared in example 5 of the present application is 38.5MPa, and compared with the test sample 1, the 28-day compressive strength of the test sample 5 is lost by 15.6%, because the hydrophobic alumina micro powder adopted in the preparation process of the modified silicon nitride hollow microsphere adopted in example 5 is added with β -alanine in the preparation process, the fluorine-containing substance with low surface energy cannot be stably modified on the surface of the hydrophobic alumina micro powder, and further the hydrophobic property of the hydrophobic film on the surface of the modified silicon nitride hollow microsphere is poor, and the hydrophobic film of the modified silicon nitride hollow microsphere is easily corroded and damaged by alkaline substances in the construction process, so that the modified silicon nitride hollow microsphere is easily subjected to water seepage and fracture, and therefore the compressive strength of the well cementation slurry is reduced.
It can be seen by combining example 1, example 6 and table 2 that the 28-day compressive strength of the well cementation slurry prepared in example 6 of the present application is 37.3MPa, and compared with test sample 1, the 28-day compressive strength of test sample 6 is lost by 18.2%, because the modified silicon nitride hollow microsphere adopted in example 6 is prepared by using a saturated sodium sulfate solution instead of a saturated lithium sulfate solution, and then the solubility of saturated sodium sulfate is in direct proportion to the temperature, crystals cannot be precipitated in the temperature raising process, hydrophobic alumina micro powder cannot be stably combined on the surface of silicon nitride micro powder, and the hydrophobic property of the hydrophobic film on the surface of the modified silicon nitride hollow microsphere is poor, and the hydrophobic film of the modified silicon nitride hollow microsphere is easily corroded and damaged by alkaline substances in the construction process, so that the modified silicon nitride hollow microsphere is easily subjected to water seepage and fracture, and the compressive strength of the well cementation slurry is reduced.
It can be seen by combining example 1, example 7 and table 2 that the 28-day compressive strength of the well cementation slurry prepared in example 7 of the present application is 37.2MPa, and compared with test sample 1, the 28-day compressive strength of test sample 7 is lost by 18.4%, and since the modified silicon nitride hollow microspheres adopted in example 7 are not subjected to a temperature raising operation in the preparation process, the saturated lithium sulfate solution cannot be precipitated and crystallized in the preparation process, so that the hydrophobic alumina micro powder is stably combined on the surface of the silicon nitride micro powder, and the compressive strength of the final well cementation slurry is reduced.
It can be seen from the combination of example 1, example 8 and table 2 that the 28-day compressive strength of the well cementation slurry prepared in example 8 of the present application is 32.2MPa, and compared with the test sample 1, the 28-day compressive strength of the test sample 8 is lost by 29.4%, because the modified silicon nitride hollow microsphere adopted in example 8 adopts the common alumina micro powder in the preparation process, and the hydrophobicity of the alumina film formed by the common alumina micro powder is not good, the corrosion resistance of the modified silicon nitride hollow micro powder is not good, and the compressive strength of the well cementation slurry is reduced.
It can be seen by combining example 1, comparative example 2 and table 2 that the 28-day compressive strength of the well cementation slurry prepared in comparative example 2 of the present application is 14.2MPa, and compared with the test sample 1, the 28-day compressive strength of the control sample 2 is lost by 68.9%, because the unmodified silicon nitride hollow microspheres are adopted in the lightening admixture of example 8, the unmodified silicon nitride hollow microspheres are easily corroded by high-concentration alkaline substances in the well cementation slurry, so that the silicon nitride hollow microspheres are cracked or seeped water, the compressive strength of the silicon nitride hollow microspheres is greatly reduced, and further the compressive strength of the well cementation slurry cannot meet the requirement of deep well cementing.
The present embodiment is only for explaining the present application, and it is not limited to the present application, and those skilled in the art can make modifications of the present embodiment without inventive contribution as needed after reading the present specification, but all of them are protected by patent law within the scope of the claims of the present application.
Claims (8)
1. The composite hollow lightening agent for well cementation is characterized by comprising the following raw materials in parts by weight: 50-60 parts of modified silicon nitride hollow microspheres, 15-25 parts of fly ash, 10-20 parts of micro silicon powder, 2-4 parts of stabilizing agent, 2-5 parts of drag reducer and 1-3 parts of fluid loss agent.
2. The composite hollow lightening agent for well cementation according to claim 1, characterized in that: the modified silicon nitride hollow microsphere comprises the following components in percentage by weight: 40-50% of modified silicon nitride micro powder and 50-60% of phosphate;
the modified silicon nitride micro powder is obtained by coating a hydrophobic film on the surface of the silicon nitride micro powder.
3. The composite hollow lightening agent for well cementation according to claim 2, characterized in that: the hydrophobic film is an aluminum oxide film, and the aluminum oxide film is prepared from hydrophobic aluminum oxide micro powder.
4. The composite hollow lightening agent for well cementation according to claim 2, characterized in that: the modified silicon nitride hollow microsphere is prepared by the following method:
s1: pretreating silicon nitride micro powder; preparing hydrophobic alumina micro powder;
s2: soaking the pretreated silicon nitride micro powder and hydrophobic alumina micro powder in a saturated lithium sulfate solution for 5-6h, slowly heating to 70-80 ℃ in the soaking process, keeping the temperature for 1-2h, drying to obtain modified silicon nitride micro powder, and then uniformly mixing the modified silicon nitride micro powder and phosphate at the temperature of 70-80 ℃ to obtain a liquid mixture, wherein the mass ratio of the silicon nitride micro powder to the hydrophobic alumina micro powder is 1:1;
s3: and granulating and sintering the liquid mixture to obtain the modified silicon nitride hollow microspheres.
5. The composite hollow lightening agent for well cementation according to claim 4, characterized in that: the hydrophobic alumina micro powder in the S1 is prepared by the following steps:
dispersing alumina micro powder in a beta-alanine solution with the mass concentration of 30-35%, then adding a trifluorobromoethane solution with the mass concentration of 0.2-0.025%, reacting at 25 ℃ for 10-12h, washing the obtained product with distilled water for multiple times, and drying to obtain hydrophobic alumina micro powder; wherein the mass ratio of the alumina micro powder to the trifluorobromochloroethane solution is 1: (0.02-0.5).
6. The composite hollow lightening agent for well cementation according to claim 4, characterized in that: the pretreatment of the silicon nitride micro powder in the S1 comprises the following steps:
dispersing silicon nitride micro powder in hydrofluoric acid solution, soaking for 0.5-1h, repeatedly washing with distilled water until the pH of the washing water is 7 +/-0.5, and drying the silicon nitride micro powder.
7. The composite hollow lightening agent for well cementation according to claim 2, characterized in that: the phosphate is at least one of potassium phosphate and sodium phosphate.
8. A method for preparing the composite cementing hollow lightening agent according to any one of claims 1 to 7, which is characterized in that: the modified silicon nitride hollow microspheres, the fly ash, the micro silicon powder, the stabilizer, the drag reducer and the fluid loss additive are mixed according to a ratio and stirred uniformly to obtain the composite hollow drag reducer for well cementation.
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Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1168362A (en) * | 1996-01-09 | 1997-12-24 | 住友电气工业株式会社 | High-strength porous silicon nitride body and process for producing the same |
| US20120018155A1 (en) * | 2010-07-21 | 2012-01-26 | Rahul Chandrakant Patil | Cement compositions with a high-density additive of silicon carbide or sintered bauxite |
| CN103880362A (en) * | 2014-04-10 | 2014-06-25 | 山东理工大学 | Method for preparing low-density cement briquette for oil well cementation by use of silicon nitride ceramic microbeads |
| CN108947540A (en) * | 2018-10-12 | 2018-12-07 | 福建省泉州市契合工贸有限公司 | A kind of hydrophobic porous ceramic and its preparation process |
-
2022
- 2022-11-11 CN CN202211415217.XA patent/CN115572092B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1168362A (en) * | 1996-01-09 | 1997-12-24 | 住友电气工业株式会社 | High-strength porous silicon nitride body and process for producing the same |
| US20120018155A1 (en) * | 2010-07-21 | 2012-01-26 | Rahul Chandrakant Patil | Cement compositions with a high-density additive of silicon carbide or sintered bauxite |
| CN103880362A (en) * | 2014-04-10 | 2014-06-25 | 山东理工大学 | Method for preparing low-density cement briquette for oil well cementation by use of silicon nitride ceramic microbeads |
| CN108947540A (en) * | 2018-10-12 | 2018-12-07 | 福建省泉州市契合工贸有限公司 | A kind of hydrophobic porous ceramic and its preparation process |
Non-Patent Citations (1)
| Title |
|---|
| 张艾飞,刘吉平: "纳米复合陶瓷制备工艺研究现状和发展前景", 现代化工 * |
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