A high-toughness impact-resistant cement paste system

Abstract

The application discloses a high-toughness impact-resistant cement slurry system, which comprises, in parts by weight, oil well cement 100-120 parts, perlite 18-26 parts, microsilica 12-18 parts, a fluid loss additive 0.8-1.2 parts, a dispersing agent 0.3-0.9 parts and water 55-105 parts, and is characterized in that the system further comprises biological expansion particles 15-65 parts; the biological expansion particles comprise glass microbeads, the glass microbead shell has cracks, and the inside contains bacillus pasteurii, urea solution and calcium carbonate generated by the bacillus pasteurii; the volume ratio of the calcium carbonate generated by the bacillus pasteurii to the volume of the glass shell is 80-95%; and the diameter of the glass shell is 0.15-0.2 mm. The cement slurry system has good impact resistance and toughness and effectively improves the cementing sealing strength.

Description

TECHNICAL FIELD

[0001] The present application relates to a cementing slurry system for oil and gas wells, in particular to a high-toughness impact-resistant cementing slurry system. BACKGROUND

[0002] With the consumption of oil and gas resources, the terrain suitable for exploitation is becoming less and less, and the exploitation of oil and gas layers with complex geological structures is gradually increasing, and the cementing difficulty is also increasing. The requirements for the cementing slurry system are also getting higher and higher. Because it needs to bear a large pressure, the stability of its own structure and the bonding strength and sealing performance between the well and the well wall are all very high, so as to ensure that the oil and gas cannot flow along the inside of the hardened cement structure and between the cement structure and the well wall.

[0003] The cementing slurry itself has been developed for many years, and the structural strength and toughness can be adjusted by various additives. The cementing slurry system of the whole length of the well body is basically consistent in proportion, and there is no targeted design for the segmented conditions of the well body. Based on this idea, the cementing slurry system of the whole length of the well body is designed based on the most adverse environmental conditions. In this way, the cementing slurry at the bottom, middle and top hardens under different environmental conditions, and the strength and toughness of the cement stone after hardening will have a big difference. The bottom section is in a high-temperature and high-pressure environment, and is easy to be damaged. When the gas breaks through the bottom end, it is easy to leak when the structural strength of the middle and top sections is insufficient.

[0004] Common chemical additives, when added to cement, not only bring effects, but also introduce new problems. The cementing slurry system of a certain section can stably achieve the effect of cementing and sealing, SUMMARY

[0005] The embodiment of the present application provides a high-toughness impact-resistant cementing slurry system, which solves the problems of poor cementing strength and sealing effect of the middle and upper sections in the prior art, and realizes the effects of stable strength and tight sealing of the middle and upper sections.

[0006] The embodiment of the present application provides a high-toughness impact-resistant cementing slurry system, which includes oil well cement 100-120 parts by weight, perlite 18-26 parts by weight, microsilica 12-18 parts by weight, fluid loss additive 0.8-1.2 parts by weight, dispersant 0.3-0.9 parts by weight, and water 55-105 parts by weight, and further includes biological expansion particles 15-65 parts by weight; the biological expansion particles include glass microbeads, the glass microbead shell has cracks, and the inside contains bacillus pasteurii, urea solution and calcium carbonate produced by bacillus pasteurii, the volume ratio of the calcium carbonate produced by bacillus pasteurii to the volume of the glass shell is 80-95%, and the diameter of the glass shell is 0.15-0.2 mm.

[0007] Preferably, the biologically expanded particles can increase the volume of the glass microsphere shell in the cement slurry system by 3.35*10-5 to 2.14*10-3 cubic millimeter in 24 hours when the temperature of the cement slurry system is in the range of 35-40 degrees Celsius.

[0008] Preferably, the urea solution contains 1.5-3.5 parts by weight of urea, 0.15-0.25 parts by weight of calcium chloride, and 100 parts by weight of water.

[0009] Preferably, the glass microsphere shell, after being immersed in water under pressure, has a water loss of not more than 2g per 100g in an environment with a relative humidity of air of more than 95% in 24 hours.

[0010] Preferably, the intact glass microsphere shell has a compressive strength in the range of 45-65Mpa.

[0011] Preferably, the unbroken glass microsphere has a density of 1.2-1.3g / cm3.

[0012] Preferably, the biologically expanded particle preparation process is as follows:

[0013] Step one, breaking the glass microsphere: put the glass microspheres into a hard cylinder, flatten the surface, the cylinder diameter is 10-30cm, the cylinder inner diameter is the same as the outer diameter of the lower pressing surface of the pressing machine; start from 5Mpa, increase the pressure by 5Mpa each time, gradually increase the pressure to 60-95% of the compressive strength value of the glass microsphere, and maintain each pressure increase for 2-5min;

[0014] Step two, screening of broken glass microspheres: immerse the pressure-treated microspheres in pure water in a sealed container, increase the water pressure to 1.5-4.5Mpa, and hold the pressure for 10-90min;

[0015] Take out all the glass microspheres, pour them into a calcium hydroxide solution with a density of 1.4-1.6g / cm3, take out the floating particles, and the remaining particles are suspended or sink to the bottom of the solution, take out the suspended and bottom-sunk particles, and dry the surface;

[0016] Put the surface-dried particles into a calcium hydroxide solution with a density of 1.6-2.0g / cm3, take out the floating particles for standby, and filter out the part that sinks to the bottom of the solution;

[0017] Take out the floating particles, rinse them with pure water, soak them for 2-5h, rinse them with pure water, dry them, and weigh them for standby; calculate the weight loss of drying, and convert it to the water volume V of the broken glass microspheres;

[0018] Step three, filling bacteria liquid: the broken glass beads obtained by screening are soaked in the prepared Bacillus pasteurii bacteria liquid, the mass of the broken glass beads per unit volume is detected every 30 minutes, the volume of the bacteria liquid in the broken glass beads is calculated, and the volume reaches 85-100% of the water-containing volume V calculated in step two;

[0019] Step four, particle culture: the glass beads filled with bacteria liquid are immersed in urea solution, the mass ratio of which is 2% urea solution containing 0.2% calcium chloride;

[0020] The urea solution submerges the top surface of the glass beads by 5±2mm;

[0021] Every 12 hours, the urea solution is replaced, and the mass of the glass beads is weighed, until the incremental volume of the glass beads accounts for 80-95% of the water-containing volume V;

[0022] The incremental volume is calculated as follows:

[0023] Vincremental=(mbeadsfinal-mbeadsinitial) / (ρcalcium carbonate-ρbacteria liquid);

[0024] mbeadsfinal: the final mass of the glass beads; mbeadsinitial: the initial mass of the glass beads; ρcalcium carbonate: the density of the biological calcium carbonate secreted by the strain; ρbacteria liquid: the density of the bacteria liquid;

[0025] Step five, particle drying: after the culture, the glass beads are drained of the urea solution and dried by blowing cold air at 20-25 degrees Celsius until the surface is dry, and then collected for use;

[0026] Step six, cement paste system stirring: the glass bead particles after surface drying treatment are added to the cement paste system and mixed according to the preset proportion.

[0027] Preferably, before drying in step five, the wet mass m after draining is weighed, urea powder is mixed, and the surface is mixed with urea powder particles again after low-temperature drying, and the mass of the adhered urea is weighed again to form urea particle weight gain, the weight gain is 5-15g per hundred grams.

[0028] Preferably, in step four, during the particle culture process, the urea solution contains 15-30% iron powder particles by volume, the particle size is 0.02-0.0.05mm, and the urea solution flows from bottom to top continuously, so that the iron powder flows and disperses between the glass beads, and the biological calcium carbonate adheres to the iron powder;

[0029] Preferably, in step five, the biological expansion particles are magnetized before stirring.

[0030] The one or more technical solutions provided in the embodiments of the present application have at least the following technical effects or advantages: by adding the bio-expanding particles, the continuity of the cement slurry system is improved, and the bio-expanding particles have a micro-expanding effect, good impact resistance and toughness, and can effectively realize well cementing sealing. BRIEF DESCRIPTION OF DRAWINGS

[0031] Figure 1 Structure diagram of bio-expanding particles;

[0032] Figure 2 Diagram of bio-expanding particles in the state of cement slurry;

[0033] Figure 3 Diagram of vertical test block segmentation;

[0034] Figure 4 Diagram of casing and cement stone bonding strength test method. DETAILED DESCRIPTION

[0035] In order to facilitate the understanding of the present application, the present application will be described more fully below with reference to the accompanying drawings. The preferred embodiments of the present application are shown in the drawings. However, the present application can be realized in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided so that the disclosure of the present application can be more thoroughly and completely understood.

[0036] It should be noted that when an element is referred to as being "fixed" to another element, it can be directly on the other element or there can be an intervening element. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or there can be an intervening element. The terms "vertical", "horizontal", "left", "right", and similar expressions used herein are for illustrative purposes only and are not intended to be limiting.

[0037] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used in the description of the application herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items.

[0038] Embodiment one

[0039] As Figures 1-2As shown, a high-toughness impact-resistant cement slurry system includes, by weight parts, oil well cement 100-120 parts, perlite 18-26 parts, microsilica 12-18 parts, fluid loss additive 0.8-1.2 parts, dispersant 0.3-0.9 parts, water 55-105 parts, and further includes biological expansion particles 15-65 parts; the biological expansion particles include glass microbeads, the glass microbead shell has cracks, and the interior contains Bacillus pasteurii, urea solution, and calcium carbonate produced by Bacillus pasteurii, the volume ratio of the calcium carbonate produced by Bacillus pasteurii to the volume of the glass shell being 80-95%; the diameter of the glass shell is 0.15-0.2 mm.

[0040] When the temperature is in the range of 35-40 degrees Celsius, the biological expansion particles can increase the outer diameter of the glass microbead shell by 0.02-0.08 mm and increase the volume by 3.35·10 -5 -2.14·10 -3 mm3 in 24 hours in the cement slurry system. The urea solution contains 1.5-3.5 parts by weight of urea, 0.15-0.25 parts by weight of calcium chloride, and 100 parts by weight of water. The glass microbead shell, after being soaked with water under pressure, has a water loss of no more than 2 g per 100 g in an environment with an air relative humidity of more than 95% for 24 hours. The intact glass microbead shell has a compressive strength in the range of 45-65 MPa.

[0041] Because the biological calcium carbonate produced by Bacillus pasteurii after absorbing urea can bond the glass shell and other particles in the cement slurry system, the interface has strong continuity and high structural strength, and internal microcracks are avoided. At the same time, the biological expansion particles grow outward and expand in volume, so that the cement slurry system has an expansion effect. Because the growth process of the biological expansion particles is continuous, the expansion is slow during the formation of the overall strength of the cement slurry, the internal structure is continuous, and microcracks are not generated, and the cement stone is tightly pressed against the well wall.

[0042] In addition, the biological calcium carbonate also has an organic combination effect with the well wall at the interface where the cement stone is attached to the well wall, providing a more stable bonding interface and further improving the sealing effect to avoid gas channeling.

[0043] The supply of growth nutrients for biological calcium carbonate is a key factor limiting its growth, so by controlling the amount of Bacillus pasteurii and urea solution in the glass shell, the expansion amount and structural strength of the cement slurry system can be regulated, and this result can be adjusted by adaptation. In addition, the selection of the grouting area needs to be careful, and the growth temperature of Bacillus pasteurii is in the range of 35-45 degrees Celsius. That is, for a certain area, the cement slurry system can be injected to specifically strengthen the well cementing strength and sealing effect of the area.

[0044] Example Two

[0045] The preparation of bio-expanding particles includes several processes such as breaking of glass microbeads, filling of bacteria solution, particle culture and drying, and finally adding into cement paste system for stirring. The density of unbroken glass microbeads is 1.2-1.3 g / cm 3 .

[0046] Step one, breaking of glass microbeads: put the glass microbeads into a hard cylinder (steel mold or iron cylinder) as a whole, and flatten the surface. The cylinder diameter is 10-30 cm, and the inner diameter of the cylinder is the same as the outer diameter of the lower pressing surface of the pressing machine. Start from 5 MPa, and increase the pressure by 5 MPa each time, gradually increase the pressure to 60-95% of the compressive strength value of the glass microbeads. Maintain the pressure for 2-5 minutes each time. (The pressure required for cracking and breaking of glass microbeads is different for different glass materials, and the cracking and breaking forms are also different. According to the time and amount of subsequent liquid entering, the pressure value is adjusted as a reference.)

[0047] Step two, screening of broken glass microbeads: immerse the barrel-pressed microbeads in pure water, seal the container, and increase the water pressure to 1.5-4.5 MPa, and maintain the pressure for 10-90 minutes.

[0048] Take out all the glass microbeads, and pour them into a calcium hydroxide solution with a density of 1.4-1.6 g / cm 3 . Take out the floating particles, and take out the remaining particles suspended or settled at the bottom of the solution. Dry the surface.

[0049] Put the surface-dried particles into a calcium hydroxide solution with a density of 1.6-2.0 g / cm 3 . Take out the floating particles for standby, and filter out the part settled at the bottom of the solution (completely broken particles will sink to the bottom of the solution, with a density of 2.35-2.5 g / cm 3 ).

[0050] Take out the floating particles, rinse them with pure water, soak them for 2-5 hours, rinse them with pure water, dry them, weigh them (mball), and use them as standby. Simultaneously calculate the weight loss of drying, and convert it into the water volume V of broken glass microbeads.

[0051] Step three, filling of bacteria solution: immerse the broken glass microbeads obtained by screening in the prepared Bacillus pasteurii bacteria solution. Detect the mass of the broken glass microbeads per unit volume every 30 minutes. (Pour a part of the glass microbeads into a 1L leak cylinder with a through hole, take out and filter the water to weigh, and then calculate the weight gain of the glass microbeads per unit volume. Calculate the bacteria solution volume (weight gain / bacteria solution density) of the broken glass microbeads, and the volume reaches 85-100% of the water volume V calculated in step two.

[0052] The culture method of the bacterial solution can refer to the culture method in CN112047654B.

[0053] Step four, particle culture: the glass beads filled with bacterial solution are immersed in a urea solution with a mass ratio of 2% urea solution containing 0.2% calcium chloride;

[0054] The glass bead particles containing the bacterial solution are tightly packed, and the urea solution is submerged by 5±2mm above the top surface of the glass beads;

[0055] Every 12 hours, replace the urea solution, and weigh the mass of the glass beads mbeads, until the incremental volume of the glass beads accounts for 80-95% of the water volume V;

[0056] The incremental volume is calculated as follows:

[0057] Vincremental=(mbeadsfinal-mbeadsinitial) / (pcalcium carbonate-pbacterial solution);

[0058] mbeadsfinal: final mass of the glass beads; mbeadsinitial: initial mass of the glass beads; pcalcium carbonate: density of the biological calcium carbonate secreted by the strain; pbacterial solution: density of the bacterial solution;

[0059] Step five, particle drying: after culture, the glass beads are drained of the urea solution, blown with cold air at 20-25 degrees Celsius to dry, and collected after the surface is dry for later use;

[0060] (Before drying, soak in a urea solution with a higher concentration for 5-10 minutes, drain and weigh mmoist, mix urea powder, and then dry at low temperature to form a surface mixed with urea powder particles, weigh again to obtain the mass of the adhered urea, form a urea particle weight gain, the weight gain is 5-15g per hundred grams, this part of urea serves as a source of nutrition for the growth of the strain, and the urea itself has a retarding effect, forming an environmental area on the surface of the microbeads, facilitating the production of the strain)

[0061] Step six, cement paste system stirring: the glass bead particles after surface drying treatment are added to the cement paste system and mixed according to the preset ratio.

[0062] Wherein, the appropriate pressure at which the glass beads break open is compared, and the basic compressive strength of the glass beads needs to be tested. First, put the glass beads into a steel cylindrical mold with an inner diameter of 10cm, vibrate on the vibration table and supplement the glass beads until the filling height of the glass beads is maintained at 10cm; after filling, pressurize the glass beads, increase the pressure by 0.2-0.5MPa per second until the pressure of the press machine decreases, and the turning point pressure is taken as the overall compressive strength of the glass beads. This overall compressive strength is used as the basis for calculating the pressure at which the glass beads break open.

[0063] Example three

[0064] During the cultivation of the bacterial strains within the granules, the growth rate of the strains is not entirely uniform, resulting in variations in the amount of bio-calcium carbonate within the glass microspheres, and consequently, differences in the density of the glass microspheres. During mixing and grouting, particle stratification easily occurs, with denser particles at the bottom and less dense particles at the top. Inconsistent growth rates of the bacterial strains also lead to differences in the expansion rate of the particles during cement setting and hardening. Ultimately, this results in inconsistent structural strength and expansion of the cement stone at different locations, causing variations in internal stress at different heights within the cement stone. In severe cases, stress concentration can occur in localized areas, leading to internal cracks under significant loads.

[0065] Therefore, further improvements were made to the bio-expanded particles. In step four, during the particle cultivation process, the urea solution contained 15-30% by volume iron powder particles with a particle size of 0.02-0.05 mm. The urea solution flowed continuously from bottom to top, causing the iron powder to disperse and flow between the glass microspheres, so that the bio-calcium carbonate adhered to the iron powder.

[0066] In step five, the bio-expanded particles are magnetized before stirring (commercially available magnetization equipment is acceptable; the degree of magnetization can be adjusted through adaptation testing; vertically cast 30*10*10cm). 3 The specimen was left to stand for 2 hours. Five separators were inserted horizontally to divide the specimen into six equal parts. Each equal part was weighed. Figure 3 As shown. The evaluation criterion is that the difference between the mass of the top and bottom test blocks should not exceed 2-5% of the average mass of all test blocks. In this way, the bio-expanding particles in the uniformly mixed material can be basically evenly dispersed throughout the material, with magnetic attraction between them, effectively ensuring that the expansion amount of the bio-expanding particles is basically consistent in the longitudinal direction. Of course, the magnetic force can also be calculated by detecting the expansion amount of the upper and lower test blocks, but the mass basically represents the amount of filling inside the bio-expanding particles and can also basically reflect the amount of outward growth. However, measuring the mass is easier to detect on-site than measuring the expansion amount, facilitating on-site construction and debugging.

[0067] Example 4

[0068] In addition, oil well grouting typically uses steel pipes. By magnetizing the steel pipes, bio-expanding particles containing iron powder, but which do not need to be magnetized, can be enriched on the steel pipe walls, strengthening the interface strength between multiple layers of casing and making them more impact-resistant.

[0069] Through experiments, cement grout was poured between two steel pipes with an outer diameter difference of 20 cm and an axial height of 50 cm. The control group poured cement grout without added bio-expanding particles; the second group (experimental group one) poured cement grout with added bio-expanding particles (35 parts by weight); and the third group (experimental group two) poured cement grout with added bio-expanding particles (35 parts by weight). The bio-expanding particles contained iron powder and were not magnetized. The tops of the inner and outer sleeves were magnetized (using electromagnets to make the sleeves magnetic), cured at 40 degrees Celsius for 72 hours, and then the inner steel pipe was pressed down using a press to subject the cement stone and the inner steel pipe to shear force. The testing apparatus was as follows. Figure 4 As shown. The ultimate shear bearing strengths of the control group, experimental groups one and two were 2.1 MPa, 3.4 MPa, and 4.1 MPa, respectively.

[0070] The above tests show that by using magnetic adsorption to absorb bio-expanding particles, the particles can adhere to the steel pipe to produce bio-calcium carbonate. Combined with the formation process of components such as hydrated calcium silicate in cement slurry, this reduces the co-directional crystallization growth of calcium hydroxide at the interface, significantly improving the interface strength, and thus enhancing the impact resistance and sealing effect.

[0071] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. For those skilled in the art, the present invention can have various modifications and variations. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A high-toughness, impact-resistant cement slurry system, comprising, by weight, 100-120 parts oil well cement, 18-26 parts perlite, 12-18 parts microsilica, 0.8-1.2 parts water-reducing agent, 0.3-0.9 parts dispersant, and 55-105 parts water, characterized in that, It also includes 15-65 parts of bio-expanded particles; the bio-expanded particles include glass microspheres, the outer shell of the glass microspheres has cracks, and the interior contains Bacillus pasteurellii, urea solution and calcium carbonate produced by Bacillus pasteurellii, the volume ratio of calcium carbonate produced by Bacillus pasteurellii accounts for 80-95% of the volume of the outer shell of the glass microspheres; the diameter of the outer shell of the glass microspheres is 0.15-0.2 mm. The preparation process of the bio-expanded particles is as follows: Step 1: Breaking the glass microspheres: Place the glass microspheres into a rigid cylinder, flatten the surface, and make the cylinder diameter 10-30cm. The inner diameter of the cylinder is the same as the outer diameter of the pressing surface of the press. Start from 5 MPa and gradually increase the pressure by 5 MPa at each level until the pressure reaches 60-95% of the compressive strength of the glass microspheres. Each pressurization time is 2-5 minutes. Step 2, Screening of broken glass microspheres: Immerse the pressurized glass microspheres in the container into pure water, seal the container, increase the water pressure to 1.5-4.5 MPa, and hold the pressure for 10-90 minutes; All the glass microspheres were removed and poured into a container with a density of 1.4-1.6 g / cm³. 3 In a calcium hydroxide solution, floated particles are removed, while the remaining particles remain suspended or sink to the bottom of the solution. The suspended and sunken particles are then removed and their surfaces are dried. After the surface is dried, the granules are placed in a container with a density of 1.6-2.0 g / cm³. 3 In a calcium hydroxide solution, remove floating particles for later use, and filter out the portion that sinks to the bottom of the solution. Floating particles are removed, rinsed with pure water and soaked for 2-5 hours. After soaking, they are removed, rinsed with pure water, dried and weighed for later use. Simultaneously, the weight loss during drying is calculated and converted into the water volume V of the broken glass microspheres. Step 3: Filling with bacterial solution: The obtained broken glass microbeads are immersed in the prepared Bacillus pasteurellis bacterial solution. The mass of a unit volume of broken glass microbeads is measured every 30 minutes. The volume of bacterial solution inside the broken glass microbeads is calculated. The volume should reach 85-100% of the water content V calculated in Step 2. Step 4, Granule Culture: Immerse glass microbeads filled with bacterial solution in urea solution (2% urea solution, containing 0.2% calcium chloride by mass). During granule culture, the urea solution contains 15-30% iron powder particles (0.02-0.05 mm in diameter) by volume. The urea solution flows continuously from bottom to top, causing the iron powder to disperse and flow between the glass microbeads, allowing the bio-calcium carbonate to adhere to the iron powder. The urea solution submerged the top surface of the glass microspheres by 5±2 mm. Replace the urea solution every 12 hours and weigh the glass microspheres until the increased volume of the glass microspheres accounts for 80-95% of the water volume V. The incremental volume is calculated as follows: V 增量 =(m) 微珠终 -m 微珠初 ) / (ρ 碳酸钙 -r 菌液 ); m 微珠终 : The final mass of the glass microspheres; m 微珠初 Initial mass of glass microspheres; ρ 碳酸钙 The density of biogenic calcium carbonate secreted by the strain; ρ 菌液 The density of the bacterial solution; Step 5: Particle drying: After cultivation, the glass microbeads are drained of urea solution and dried with cold air at 20-25 degrees Celsius until the surface is dry. They are then collected for later use.

2. The high-toughness, impact-resistant cement slurry system according to claim 1, characterized in that, When the temperature of the cement slurry system is within the range of 35-40 degrees Celsius, the bio-expanding particles can increase the volume of the glass microsphere shell by 3.35 × 10⁻⁶ m³ / h in the cement slurry system over 24 hours. -5 Up to 2.14×10 -3 cubic millimeters.

3. The high-toughness, impact-resistant cement slurry system according to claim 1, characterized in that, The urea solution contains 1.5-3.5 parts by weight of urea, 0.15-0.25 parts by weight of calcium chloride, and 100 parts by weight of water.

4. The high-toughness, impact-resistant cement slurry system according to claim 1, characterized in that, The glass microsphere shell, after being pressure-soaked and fully saturated with water, loses no more than 2g of water per 100g in an environment with a relative humidity of over 95% for 24 hours.

5. The high-toughness, impact-resistant cement slurry system according to claim 1, characterized in that, The complete glass microsphere shell has a compressive strength in the range of 45-65 MPa.

6. The high-toughness, impact-resistant cement slurry system according to claim 1, characterized in that, The density of undamaged glass microspheres is 1.2-1.3 g / cm³. 3 .

7. The high-toughness, impact-resistant cement slurry system according to claim 1, characterized in that, In step five, before drying and after draining, weigh m 湿 The mixture is then mixed with urea powder and dried at low temperature to allow urea powder particles to adhere to the surface. The mixture is then weighed again to obtain the mass of the urea adhering to it, resulting in an increase in the weight of the urea particles. The increase in weight is 5-15g per 100g.

8. The high-toughness, impact-resistant cement slurry system according to claim 1, characterized in that, In step five, the bio-expanded particles are magnetized after surface drying.

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