阅读说明：本技术 一种固井水泥用纳米颗粒增韧材料的制备方法 (Preparation method of nano-particle toughening material for well cementation cement ) 是由 辛巧玲 于 2019-07-29 设计创作，主要内容包括：本发明涉及一种固井水泥用纳米颗粒增韧材料的制备方法,属于石油开采领域的油气井固井技术领域。本发明将稻壳灰和碱液反应后浸渍介孔纳米铁基固溶体,浸渍后再和盐酸混合反应得到改性介孔纳米铁基固溶体,再进行皂化反应,制得固井水泥用纳米颗粒增韧材料,本发明由于脂肪酸皂的引入,纳米颗粒的表面活性增高,表面能降低,因此分散性得到提高,同时具有极佳的耐高温性能,本发明制备的颗粒增韧材料是纳米级颗粒,通过纳米颗粒材料在水泥中有效的填充,在水泥基材料中可形成网络交织状骨架结构,从而提高水泥的韧性,同时,本发明中铁基固溶体可与水泥水化反应形成较为致密的水化产物,而且还能起到填充和侨联的作用,具有广阔的应用前景。(The invention relates to a preparation method of a nanoparticle toughening material for well cementation cement, and belongs to the technical field of oil and gas well cementation in the field of oil exploitation. The invention impregnates the mesoporous nanometer iron-based solid solution after reacting the rice hull ash with the alkali liquor, mixes the mesoporous nanometer iron-based solid solution with the hydrochloric acid after impregnation to react to obtain the modified mesoporous nanometer iron-based solid solution, and then carries out saponification reaction to obtain the nanoparticle toughening material for well cementation cement.)

1. A preparation method of a nano-particle toughening material for well cementation cement is characterized by comprising the following specific preparation steps:

(1) Mixing the reaction solution and the mesoporous nano iron-based solid solution according to the mass ratio of 5:1, putting the mixture into an ultrasonic oscillator, carrying out ultrasonic oscillation and dipping for 1-2 h at the frequency of 30-40 kHz, filtering, separating to obtain filter residue, mixing the dipped filter residue with hydrochloric acid with the concentration of 0.5mol/L, stirring and reacting for 15-20 min, and filtering and separating to obtain reaction filter residue;

(2) Placing the reaction filter residue into a reaction kettle, heating to 150-160 ℃, reacting at a high temperature for 30-40 min to obtain a modified mesoporous nano iron-based solid solution, placing the modified mesoporous nano iron-based solid solution into soybean oil for soaking for 2-3 h, filtering and separating after the soaking to obtain soaking filter residue, mixing the obtained soaking filter residue with 30% by mass of sodium hydroxide solution, then placing the mixture into a beaker, stirring and reacting at 80-90 ℃ for 1-2 h, filtering and separating to obtain a reaction filter cake, namely the nano particle toughening material for well cementation cement;

The preparation steps of the reaction solution are as follows:

weighing rice hulls, washing the rice hulls with deionized water for 3-5 times, putting the rice hulls into an oven, drying for 1-2 hours at 105-110 ℃, putting the dried rice hulls into a sintering furnace after drying, igniting and sintering, collecting rice hull ash, mixing the obtained rice hull ash with a sodium hydroxide solution with the concentration of 0.2mol/L, and stirring and reacting for 20-30 min to obtain a reaction solution;

The preparation steps of the mesoporous nano iron-based solid solution are as follows:

(1) putting a 1mol/L cerium nitrate solution and a 1mol/L ferric nitrate solution into a beaker, stirring for 12-15 min to obtain a mixed solution, and mixing ammonium bicarbonate and 0.5mol/L ammonia water to obtain a precipitator;

(2) Filling a polyethylene glycol solution with the concentration of 1mol/L into a beaker with a stirrer, starting the stirrer to stir at the rotating speed of 300-400 r/min, then dropping the mixed solution and the precipitant into the beaker, controlling the dropping amount of the precipitant to ensure that the pH of the reaction solution in the beaker is 9-10, and stirring and reacting for 2-3 hours;

(3) and after the stirring reaction is finished, standing for 3-4 h, transferring into a reaction kettle lined with polytetrafluoroethylene, carrying out hydrothermal reaction, filtering and separating after the reaction is finished to obtain a filter cake, washing with water and absolute ethyl alcohol for 3-5 times respectively, drying, placing into a calcining furnace, calcining for 1-2 h at 500-600 ℃, and discharging to obtain the mesoporous nano iron-based solid solution.

2. The preparation method of the nanoparticle toughening material for well cementation cement according to claim 1, characterized in that: in the specific preparation step (1) of the nano-particle toughening material for well cementation cement, the mass ratio of a reaction liquid to a mesoporous nano iron-based solid solution is 5:1, and dipping filter residues and hydrochloric acid with the concentration of 0.5mol/L are mixed according to the mass ratio of 1: 5.

3. The preparation method of the nanoparticle toughening material for well cementation cement according to claim 1, characterized in that: in the specific preparation step (2) of the nano-particle toughening material for well cementation cement, the mass ratio of the dipping filter residue to a sodium hydroxide solution with the mass fraction of 30% is 1: 5.

4. The preparation method of the nanoparticle toughening material for well cementation cement according to claim 1, characterized in that: in the preparation step of the reaction liquid, the mass ratio of the rice hull ash to the sodium hydroxide solution with the concentration of 0.2mol/L is 1: 2.

5. The preparation method of the nanoparticle toughening material for well cementation cement according to claim 1, characterized in that: in the preparation step (1) of the mesoporous nano iron-based solid solution, the molar mass ratio of a 1mol/L cerium nitrate solution to a 1mol/L ferric nitrate solution is 1:2, and the mass ratio of ammonium bicarbonate to 0.5mol/L ammonia water is 1: 5.

6. the preparation method of the nanoparticle toughening material for well cementation cement according to claim 1, characterized in that: in the step (2) of preparing the mesoporous nano iron-based solid solution, the loading amount of the polyethylene glycol solution with the concentration of 1mol/L is 30% of the molar mass of the mixed solution.

7. the preparation method of the nanoparticle toughening material for well cementation cement according to claim 1, characterized in that: in the step (3) of preparing the mesoporous nano iron-based solid solution, the temperature of the hydrothermal reaction is 150-180 ℃, and the time of the hydrothermal reaction is 3-5 hours.

Technical Field

The invention relates to a preparation method of a nanoparticle toughening material for well cementation cement, and belongs to the technical field of oil and gas well cementation in the field of oil exploitation.

Background

The well cementation of the oil and gas well comprises casing pipe setting and cement injection, wherein in the well cementation construction, cement slurry is pumped into an annular space between a well wall and the casing pipe and finally solidified to form cement stones with certain cementing capacity and hardness. The hardened set cement plays roles of sealing various fluids in the stratum, protecting and supporting a casing, and is important for subsequent drilling and oil and gas exploitation.

the brittle materials such as set cement are easily subjected to micro-cracks and micro-annular gaps under the influence of complex conditions such as temperature, pressure, drilling, injection and production and the like under the underground, so that the integrity of the set cement is damaged, and the productivity, the production life and the safety of an oil-gas well are seriously influenced. Therefore, the research on the mechanical property of the well cementation set cement and the improvement of the integrity of the set cement body have important significance on the production and the long-term service life of the oil-water well. Since high brittleness is an inherent defect of set cement, the toughness of set cement is increased mainly by incorporating a toughening material in oil well cement.

The common cement stone toughening materials and endogenous toughening materials at present mainly comprise: fibers, nanomaterials, latex, particulate materials, and the like. The latex is an emulsion polymer, and most latex suspensions contain about 50% solids, with the suspended particles typically having a diameter of 0.05 to 0.5 μm. The latex cement can reduce the elastic modulus of the set cement, improve the bonding strength of the set cement, and has impermeability and film forming property, so that the latex cement can play a good role in preventing gas channeling. The latex cement can effectively reduce the volume shrinkage of cement paste and improve the bonding strength by about 30 percent. The latex has the defects that the latex cement paste has the problems of easy dispersion instability, easy foaming, poor temperature resistance and the like, so that the latex is aggregated and thickened, and the latex is aggregated and demulsified and the cement paste is flash coagulated along with the rise of temperature; the particle material mainly comprises inorganic particles and organic particles, and the particle size is generally 75-230 mu m. The inorganic particles commonly used in well cementation engineering mainly comprise bentonite, silica fume, microbeads, active slag and the like; the organic particles mainly comprise rubber powder, organic glass beads and the like. The granular material has the advantages of wide raw material source, low production price, reduction of the elastic modulus of the set cement, prevention of crack propagation of the set cement and the like, so that the granular material is widely applied to well cementation engineering. However, the application of the rubber particles is greatly limited due to hydrophobic surfaces, easy floating and poor temperature resistance of the rubber particles; the fiber is a soft slender body with the length-diameter ratio of more than 1000 times and the thickness of several micrometers to hundreds of micrometers. It features high strength, modulus and corrosion resistance. The fiber materials commonly used in the existing well cementation include inorganic fibers, such as glass fibers, carbon fibers and the like; synthetic fibers such as nylon fibers, polyester, polypropylene, and the like; plant fiber such as bamboo fiber and hemp fiber. The fiber has a certain toughening effect on cement stone, but the fibers mainly have the following defects: firstly, the density is low, and the slurry is not dispersed after mixing and is suspended on the surface of the slurry; secondly, the surface is hydrophobic, the wettability is poor, the slurry is easy to agglomerate when being mixed, and the pipeline is easy to block when being pumped, so that the pump is blocked, and the construction safety is influenced. Thirdly, the durability is poor, the cost is high, and the like.

therefore, there is an urgent need in the art to develop a novel brittleness-reducing and toughening material for oil well set cement, which can improve the toughness and hydrophilicity of the set cement, reduce the brittleness of the set cement, and simultaneously can not greatly reduce the strength of the set cement.

Disclosure of Invention

the invention mainly solves the technical problems, and provides a preparation method of a nano-particle toughening material for well cement, aiming at the defects that the conventional cement particle toughening material has poor temperature resistance, poor dispersibility and easy agglomeration, and the particles are more than micron-millimeter-sized materials, the mechanical property of oil well cement stone is mainly improved from a macroscopic scale or a microscopic scale, and cracks in the cement stone cannot be inhibited from generating and expanding from a macroscopic scale.

in order to solve the technical problems, the technical scheme adopted by the invention is as follows:

The specific preparation steps of the nano-particle toughening material for well cementation cement are as follows:

(1) Mixing the reaction solution and the mesoporous nano iron-based solid solution according to the mass ratio of 5:1, putting the mixture into an ultrasonic oscillator, carrying out ultrasonic oscillation and dipping for 1-2 h at the frequency of 30-40 kHz, filtering, separating to obtain filter residue, mixing the dipped filter residue with hydrochloric acid with the concentration of 0.5mol/L, stirring and reacting for 15-20 min, and filtering and separating to obtain reaction filter residue;

(2) Placing the reaction filter residue into a reaction kettle, heating to 150-160 ℃, reacting at a high temperature for 30-40 min to obtain a modified mesoporous nano iron-based solid solution, placing the modified mesoporous nano iron-based solid solution into soybean oil for soaking for 2-3 h, filtering and separating after the soaking to obtain soaking filter residue, mixing the obtained soaking filter residue with 30% by mass of sodium hydroxide solution, then placing the mixture into a beaker, stirring and reacting at 80-90 ℃ for 1-2 h, filtering and separating to obtain a reaction filter cake, namely the nano particle toughening material for well cementation cement;

The preparation steps of the reaction solution are as follows:

weighing rice hulls, washing the rice hulls with deionized water for 3-5 times, putting the rice hulls into an oven, drying for 1-2 hours at 105-110 ℃, putting the dried rice hulls into a sintering furnace after drying, igniting and sintering, collecting rice hull ash, mixing the obtained rice hull ash with a sodium hydroxide solution with the concentration of 0.2mol/L, and stirring and reacting for 20-30 min to obtain a reaction solution;

The preparation method of the mesoporous nano iron-based solid solution comprises the following steps:

(1) putting a 1mol/L cerium nitrate solution and a 1mol/L ferric nitrate solution into a beaker, stirring for 12-15 min to obtain a mixed solution, and mixing ammonium bicarbonate and 0.5mol/L ammonia water to obtain a precipitator;

(2) Filling a polyethylene glycol solution with the concentration of 1mol/L into a beaker with a stirrer, starting the stirrer to stir at the rotating speed of 300-400 r/min, then dropping the mixed solution and the precipitant into the beaker, controlling the dropping amount of the precipitant to ensure that the pH of the reaction solution in the beaker is 9-10, and stirring and reacting for 2-3 hours;

(3) And after the stirring reaction is finished, standing for 3-4 h, transferring into a reaction kettle lined with polytetrafluoroethylene, carrying out hydrothermal reaction, filtering and separating after the reaction is finished to obtain a filter cake, washing with water and absolute ethyl alcohol for 3-5 times respectively, drying, placing into a calcining furnace, calcining for 1-2 h at 500-600 ℃, and discharging to obtain the mesoporous nano iron-based solid solution.

in the specific preparation step (1) of the nano-particle toughening material for well cementation cement, the mass ratio of the reaction liquid to the mesoporous nano-iron-based solid solution is 5:1, and the mass ratio of the dipping filter residue to 0.5mol/L hydrochloric acid is 1: 5.

In the specific preparation step (2) of the nano-particle toughening material for well cementation cement, the mass ratio of the dipping filter residue to a sodium hydroxide solution with the mass fraction of 30% is 1: 5.

in the step of preparing the reaction solution, the mass ratio of the rice hull ash to the sodium hydroxide solution with the concentration of 0.2mol/L is 1: 2.

in the step (1) of preparing the mesoporous nano iron-based solid solution, the molar mass ratio of a cerium nitrate solution with the concentration of 1mol/L to an iron nitrate solution with the concentration of 1mol/L is 1:2, and the mass ratio of ammonium bicarbonate to ammonia water with the concentration of 0.5mol/L is 1: 5.

in the step (2) of preparing the mesoporous nano iron-based solid solution, the loading amount of the polyethylene glycol solution with the concentration of 1mol/L is 30% of the molar mass of the mixed solution.

In the step (3) of preparing the mesoporous nano iron-based solid solution, the temperature of the hydrothermal reaction is 150-180 ℃, and the time of the hydrothermal reaction is 3-5 hours.

the beneficial technical effects of the invention are as follows:

(1) The invention firstly takes ferric nitrate and cerous nitrate as raw materials, ammonium bicarbonate and ammonia water as precipitant, polyethylene glycol as template agent, mesoporous nano iron-based solid solution is prepared by hydrothermal synthesis and calcination, then rice hull is taken and sintered to obtain rice hull ash, the rice hull ash is reacted with alkali liquor, then the mesoporous nano iron-based solid solution is dipped, the dipped nano iron-based solid solution is mixed with hydrochloric acid for reaction, modified mesoporous nano iron-based solid solution is obtained after high temperature treatment, finally soybean oil is dipped and the saponification reaction is carried out with sodium hydroxide solution, thus preparing the nano particle toughening material for well cementation cement. The method comprises the steps of reacting rice hull ash with alkali liquor to generate reaction liquid rich in sodium silicate, soaking a nano iron-based solid solution in the reaction liquid to enable the sodium silicate to be soaked in a mesoporous structure attached to the nano iron-based solid solution, then reacting with hydrochloric acid to enable the sodium silicate to be reacted to become orthosilicic acid, finally enabling the orthosilicic acid to be decomposed into nano silicon dioxide to be fixed in mesopores of the iron-based solid solution under the action of high temperature to obtain a modified mesoporous nano iron-based solid solution, soaking the modified mesoporous nano iron-based solid solution in soybean oil to enable the soybean oil to be soaked in pores of the solid solution, carrying out saponification reaction on the soybean oil in the pores of the alkali liquor and the solid solution to generate fatty acid soap, and finally obtaining the nano particle toughening material for well cementing cement. The surface energy is reduced, so the dispersibility is improved, the particles are not easy to agglomerate in cement paste, and the iron-based solid solution and the silicon dioxide in the pores have excellent high-temperature resistance, so the temperature resistance of the toughened particle material prepared by the invention is also excellent;

(2) The particle toughening material prepared by the invention is nano-scale particles, the particle size of the particle toughening material is much smaller than that of the cement admixture, the particle size of the cement hydration product is equivalent to that of a cement hydration product, and the cement hydration product is effectively filled with nano-particle materials, subjected to particle grading and chemical reaction, a network interweaving skeleton structure can be formed in the cement-based material, so that the toughness of the cement is improved, and simultaneously, the iron-based solid solution in the nano-particle toughening material can generate hydration reaction, the silicon dioxide has volcanic ash effect and can react with calcium hydroxide generated by cement hydration to generate reaction products such as hydrated calcium silicate, hydrated calcium aluminate or hydrated calcium sulphoaluminate and the like, so that the nano-induced hydration effect is generated in the cement to form a compact hydration product, and the filling and coupling effects can be achieved, so that the toughness and the strength of the cement are improved again, and the application prospect is wide.

Detailed Description

adding a cerium nitrate solution with the concentration of 1mol/L and a ferric nitrate solution with the concentration of 1mol/L into a beaker according to the molar mass ratio of 1:2, stirring for 12-15 min to obtain a mixed solution, and mixing ammonium bicarbonate and ammonia water with the concentration of 0.5mol/L according to the mass ratio of 1:5 to obtain a precipitator; filling 1mol/L polyethylene glycol solution with the concentration of 30% of the molar mass of the mixed solution into a beaker with a stirrer, starting the stirrer to stir at the rotating speed of 300-400 r/min, then dropping the mixed solution and the precipitant into the beaker, controlling the dropping amount of the precipitant to ensure that the pH of the reaction solution in the beaker is 9-10, and stirring and reacting for 2-3 hours; standing for 3-4 hours after the stirring reaction is finished, transferring the mixture into a reaction kettle lined with polytetrafluoroethylene, heating to 150-180 ℃, carrying out hydrothermal reaction for 3-5 hours, filtering and separating after the reaction is finished to obtain a filter cake, washing the filter cake with water and absolute ethyl alcohol for 3-5 times respectively, drying, then putting the filter cake into a calcining furnace, calcining for 1-2 hours at 500-600 ℃, and discharging to obtain a mesoporous nano iron-based solid solution for later use; weighing rice hulls, washing the rice hulls with deionized water for 3-5 times, putting the rice hulls into an oven, drying for 1-2 hours at 105-110 ℃, putting the dried rice hulls into a sintering furnace after drying, igniting and sintering, collecting rice hull ash, mixing the obtained rice hull ash and a sodium hydroxide solution with the concentration of 0.2mol/L according to the mass ratio of 1:2, and stirring and reacting for 20-30 min to obtain a reaction solution; mixing the reaction solution and the standby mesoporous nano iron-based solid solution according to the mass ratio of 5:1, putting the mixture into an ultrasonic oscillator, carrying out ultrasonic oscillation and dipping for 1-2 h at the frequency of 30-40 kHz, filtering, separating to obtain filter residue, mixing the dipped filter residue with hydrochloric acid with the concentration of 0.5mol/L according to the mass ratio of 1:5, stirring and reacting for 15-20 min, and filtering and separating to obtain reaction filter residue; and (2) putting the reaction filter residue into a reaction kettle, heating to 150-160 ℃, reacting at a high temperature for 30-40 min to obtain a modified mesoporous nano iron-based solid solution, putting the modified mesoporous nano iron-based solid solution into soybean oil for soaking for 2-3 h, filtering and separating after the soaking to obtain soaking filter residue, mixing the obtained soaking filter residue with 30% by mass of sodium hydroxide solution according to the mass ratio of 1:5, putting the mixture into a beaker, stirring at 80-90 ℃ for reacting for 1-2 h, and filtering and separating to obtain a reaction filter cake, namely the nano particle toughening material for well cementation cement.