CN106634902B - The molten hydraulic cementing materials of high temperature resistant theobromine and be used for oil-well cement slurry system - Google Patents

Abstract

The invention discloses the molten hydraulic cementing materials of high temperature resistant theobromine and it is used for oil-well cement slurry system, the hydraulic cementing materials is made of by weight following each component: 100 parts of lime stone, 10~15 parts of clay, 2~4 parts of bloodstone, 1~3 part of diatomite, 0.1~2 part of ardealite, 1~2 part of gypsum, 30~35 parts of silicon powder, 0~50 part of Iron Ore Powder, 30~45 parts of calcium carbonate.The oil-well cement slurry system prepared by the hydraulic cementing materials includes: 100 parts of cementitious material, 0~1.5 part of kayexalate, 3~6 parts of 2- acrylamide-2-methyl propane sulfonic, 0.5~0.8 part of 2- acrylamide-2-methyl propane sulfonic acrylic copolymer; 1~1.5 part of butadiene-styrene latex; 0.01~0.5 part of dimethicone, 35~50 parts of water.Present invention process is convenient, low in cost, keeps good sedimentation stability in the hot environment of 80 DEG C~130 DEG C of underground by the physical suspension ability of material granule itself, is expected to be applied to the fields such as oil/gas well reservoir temporarily closes, water blockoff, unconventional gas reservoir are cemented the well.

Description

High temperature resistant and acid soluble hydraulic cementitious material and its application in oil well cement slurry system

technical field

The invention relates to the field of hydraulic cementitious materials, in particular to a high-temperature-resistant and acid-soluble hydraulic cementitious material and its application in oil well cement slurry systems.

Background technique

At present, the research and application of hydraulic acid soluble gelling materials are mainly based on acid soluble cement, which was initially used to solve the problem of circulation loss in the reservoir section of oil and gas wells. Through the gelation and hardening of cement, a certain strength of bridging plugging effect is formed at the leakage site, so as to block the natural and secondary cracks and the channels where channeling occurs; and because of its considerable acid-soluble characteristics, after acid fracturing operations, The structure can be gradually ablated and decomposed within the operation time, which can greatly reduce the damage of cement slurry to the reservoir.

After cementing, the hardened cement residue that invades the reservoir increases the difficulty of volume fracturing, which in turn affects the effect of volume fracturing and the ultimate recovery of gas wells. The use of acid-soluble cement for well cementing can effectively decontaminate the reservoir. With the enhancement of people's awareness of reservoir protection, after years of development and research, acid-soluble cement has been successfully applied in the cementing of the horizontal section of unconventional gas reservoirs. For example, the Barnett shale gas field in the United States uses acid-soluble cement to , and the production effect is good.

At present, acid-soluble cementitious materials are mainly divided into the following three categories: (1) Magnesia cement, which is widely used in well completion and workover operations (Li Zaoyuan, Jin Dongxu, Zhou Chao, etc. Magnesia cement is used for oil well plugging and temporary closure Indoor research on [J]. Southwest Petroleum University Journal (Natural Science Edition), 2011,33(5):152-156), although magnesium oxychloride cement exhibits excellent acid-soluble properties, but poor temperature resistance, in In the underground high temperature and water humidity environment, the crystal form inside the cement stone will gradually undergo irreversible changes that are not conducive to the strength development over time; although the magnesium oxysulfide cement has alleviated the trend of strength decline, its overall strength is still not good. (2) Portland cement slurry system with a small amount of calcium carbonate added to grade G cement. Although this system has many field application cases in various oil fields, its high-temperature settlement stability is poor, and the strength of cement stone is low. The rate is not ideal, and the technology is not yet mature. (3) Acid-soluble curing agent, due to the complex types of corresponding supporting treatment agents and high cost, it is difficult to popularize it in the development of oil and gas fields.

Contents of the invention

The purpose of the present invention is to provide a high-temperature resistant and acid-soluble hydraulic gelling material. Through the reasonable gradation design of the particles in the material, the hardened body of the gelling material is more stable under the premise of ensuring the effect of acid dissolution. The development of high-temperature strength can make up for the shortcomings of existing cementitious materials such as poor temperature resistance and strength decline in water-humid environments.

Another object of the present invention is to provide the application of the above-mentioned high-temperature resistant and acid-soluble hydraulic cementitious material in oil well cement slurry system. The oil well cement slurry system prepared by hydraulic cementitious materials has convenient process, low cost and excellent performance. Through the physical suspension ability of material particles, it can maintain good settlement stability in the high temperature environment of 80℃～130℃ underground. The invention breaks through the limitation of poor high-temperature sedimentation stability of the slurry of the existing acid-soluble gelling material. The invention is expected to be applied to fields such as temporary closure of oil and gas well reservoirs, water shutoff, unconventional gas reservoir cementing and the like.

In order to achieve the above technical objectives, the present invention provides the following technical solutions.

A high-temperature-resistant and acid-soluble hydraulic gelling material consists of the following components by weight:

The preparation process of the high-temperature resistant and acid-soluble hydraulic gelling material is as follows:

Produced by dry method, crush 100 parts of limestone, 10-15 parts of clay, 2-4 parts of hematite, 1-3 parts of diatomaceous earth, and 0.1-2 parts of phosphogypsum with a crusher until the particle size is less than 25mm. , after mixing, send it to the rotary kiln for calcination for 1 hour, the calcination temperature is 1350-1450°C, enter the cooling machine for cooling, rapidly cool to 50-80°C, and the cooling rate is 18-20°C/min, then add 1-2 parts of gypsum, 30- 35 parts of silicon powder, 0-50 parts of iron ore powder, and 30-45 parts of calcium carbonate are mixed and ground, so that the particle size of the product is controlled at 1-100 μm, and a high-temperature-resistant and acid-soluble hydraulic gelling material is obtained.

_The purity of CaCO3 in said limestone is at least 65%.

The content of SiO ₂ in the clay is not less than 60%, and it should be strictly dried before calcination to make the water content less than 1%.

_The content of _Fe2O3 in the hematite is 50%-70%.

The silicon powder is about 400 mesh (38 μm) particles.

The calcium carbonate is a mixture of two different particle sizes of about 1500 mesh (7 μm) and 10000 mesh (1.3 μm) to form a better gradation effect.

The above-mentioned several raw materials can be purchased from the market.

The high-temperature-resistant and acid-soluble hydraulic cementitious material is used in an oil well cement slurry system, and the oil well cement slurry system is composed of the following components by weight:

The preparation process of the oil well cement slurry system is as follows:

Weigh 0-1.5 parts of sodium polystyrene sulfonate, 3-6 parts of 2-acrylamide-2-methylpropanesulfonic acid AMPS, 0.5-0.8 parts of 2-acrylamide-2-methylpropanesulfonic acid acrylic acid copolymer AA/AMPS, 1-1.5 parts of styrene-butadiene latex, 0.01-0.5 parts of dimethyl silicone oil, dissolved in 35-50 parts of water to prepare an aqueous solution, put the aqueous solution in a high-speed stirrer, and the stirrer at a low speed (4000±200 rpm /min) rotation, and add 100 parts of hydraulic cementitious materials in 15 seconds, then continue to stir for 35 seconds under high-speed (12000 ± 500 rpm) rotation, to obtain the high temperature resistant acid-soluble oil well prepared by the present invention cement slurry system.

The invention provides a high-temperature-resistant and acid-soluble hydraulic gelling material, and prepares an oil well cement slurry system that can be used in the fields of unconventional gas reservoir cementing, reservoir temporary closure, and the like. Through the reasonable gradation of the particles, good physical suspension of the slurry is achieved, making the system adapt to the high temperature environment of 80 ℃ ~ 130 ℃ in a breakthrough, without additional adjustment of admixtures; the denser accumulation degree gives water The hardened body of the hard gelling material develops more stable high-temperature strength; adding acid-soluble materials with different particle sizes increases the acid-soluble reaction rate of the hardened body, ensuring its considerable release (acid fracturing) effect. The invention makes up for the deficiencies of the existing acid-soluble gelling materials, such as poor temperature resistance, poor settlement stability, and strength decline in a water-humid environment.

Compared with the prior art, the present invention has the following beneficial effects:

(1) The gelling material has excellent high temperature resistance, and the gray sample is based on a reasonable gradation design, relying on the physical function of the particles themselves to achieve good suspension. The existing acid-sol gelling system is difficult to adapt to the temperature environment above 80°C, but the gelling material of the present invention can maintain good stability in the downhole temperature environment of 80°C-130°C, without special admixture adjustment, and the water loss Low, engineering application performance can be adjusted.

(2) The gelling system is a hydraulic material, and has good long-term stability in the underground water-humid environment without strength decline.

(3) The selection of acid-soluble materials with different particle sizes not only increases the acid-soluble reaction rate of the hardened body, but also improves the compactness of the hardened body, which is conducive to the stable development of its strength.

(4) The oil well cement slurry system prepared by the cementitious material has broad application prospects, low cost and convenient process, and can be applied to unconventional oil and gas reservoir cementing, reservoir temporary closure and other fields.

Description of drawings

Fig. 1 is the thickening curve (experimental temperature 130 ℃, pressure 70MPa) of the synthetic product of embodiment 3.

Fig. 2 is the test result of the real-time acid solubility rate of G grade cement paste and the hardened body of Example 3.

specific implementation plan

The present invention will be further described below through embodiment and accompanying drawing.

One, the preparation of high temperature resistant and acid-soluble hydraulic cementitious material and oil well cement slurry system (the following components are parts by weight)

Example 1

It is produced by dry method. 100 parts of limestone, 15 parts of clay, 3 parts of hematite, 3 parts of diatomaceous earth and 1 part of phosphogypsum are crushed by a crusher to a block with a particle size of less than 25mm, mixed and sent to a rotary kiln for calcination 1h, the calcination temperature is 1350-1450°C, enter the cooling machine for cooling, rapidly cool to 65°C, and the cooling rate is 18-20°C/min, then add 2 parts of gypsum, 30 parts of silicon powder, and 35 parts of calcium carbonate for mixing and grinding. The particle size of the product is controlled at 1-100 μm to obtain a high-temperature-resistant and acid-soluble hydraulic gelling material.

Weigh 1 part of sodium polystyrene sulfonate, 3 parts of 2-acrylamide-2-methylpropanesulfonic acid AMPS, 0.5 part of 2-acrylamide-2-methylpropanesulfonic acid acrylic acid copolymer AA/AMPS, 1.5 parts Dissolve styrene-butadiene latex and 0.01 part of simethicone in 37 parts of water to prepare an aqueous solution, put the aqueous solution in a high-speed stirrer, turn the stirrer at a low speed (4000±200 rpm), and add it within 15 seconds 100 parts of hydraulic cementitious material, and then continue stirring for 35 seconds under high-speed (12000±500 rpm) rotation to obtain a high-temperature-resistant and acid-soluble oil well cement slurry system.

Example 2

It is produced by dry method, crushing 100 parts of limestone, 15 parts of clay, 2 parts of hematite, 3 parts of diatomaceous earth, and 1 part of phosphogypsum into lumps with a particle size of less than 25mm, mixed and sent to the rotary kiln for calcination 1h, the calcination temperature is 1350-1450°C, enter the cooling machine for cooling, rapidly cool to 68°C, and the cooling rate is 18-20°C/min, then add 2 parts of gypsum, 30 parts of silicon powder, and 40 parts of calcium carbonate for mixing and grinding. The particle size of the product is controlled at 1-100 μm to obtain a high-temperature-resistant and acid-soluble hydraulic gelling material.

Weigh 1 part of sodium polystyrene sulfonate, 3.5 parts of 2-acrylamide-2-methylpropanesulfonic acid AMPS, 0.5 part of 2-acrylamide-2-methylpropanesulfonic acid acrylic acid copolymer AA/AMPS, 1.5 parts Dissolve styrene-butadiene latex and 0.05 parts of simethicone in 50 parts of water to prepare an aqueous solution, put the aqueous solution in a high-speed stirrer, turn the stirrer at a low speed (4000±200 rpm), and add it within 15 seconds 100 parts of hydraulic cementitious material, and then continue stirring for 35 seconds under high-speed (12000±500 rpm) rotation to obtain a high-temperature-resistant and acid-soluble oil well cement slurry system.

Example 3

Produced by dry method, crush 100 parts of limestone, 15 parts of clay, 4 parts of hematite, 3 parts of diatomaceous earth, and 1.5 parts of phosphogypsum into lumps with a particle size of less than 25mm, mix them and send them to the rotary kiln for calcination 1h, the calcination temperature is 1350-1450°C, enter the cooling machine for cooling, rapidly cool to 60°C, and the cooling rate is 18-20°C/min, then add 2 parts of gypsum, 30 parts of silicon powder, and 35 parts of calcium carbonate for mixing and grinding. The particle size of the product is controlled at 1-100 μm to obtain a high-temperature-resistant and acid-soluble hydraulic gelling material.

Weigh 1 part of sodium polystyrene sulfonate, 3 parts of 2-acrylamide-2-methylpropanesulfonic acid AMPS, 0.6 part of 2-acrylamide-2-methylpropanesulfonic acid acrylic acid copolymer AA/AMPS, 1.5 parts Dissolve styrene-butadiene latex and 0.01 part of simethicone in 37 parts of water to prepare an aqueous solution, put the aqueous solution in a high-speed stirrer, turn the stirrer at a low speed (4000±200 rpm), and add it within 15 seconds 100 parts of hydraulic cementitious material, and then continue stirring for 35 seconds under high-speed (12000±500 rpm) rotation to obtain a high-temperature-resistant and acid-soluble oil well cement slurry system.

Example 4

Produced by dry method, crush 100 parts of limestone, 15 parts of clay, 4 parts of hematite, 3 parts of diatomaceous earth, and 1.5 parts of phosphogypsum into lumps with a particle size of less than 25mm, mix them and send them to the rotary kiln for calcination 1h, calcination temperature 1350～1450℃, enter into the cooling machine for cooling, rapid cooling to 60℃, cooling rate 18～20℃/min, then add 1 part of gypsum, 35 parts of silicon powder, 30 parts of iron ore powder, 30 parts of calcium carbonate Grinding is carried out after mixing, so that the particle size of the product is controlled at 1-100 μm, and a high-temperature-resistant and acid-soluble hydraulic gelling material is obtained.

Weigh 1 part of sodium polystyrene sulfonate, 5 parts of 2-acrylamide-2-methylpropanesulfonic acid AMPS, 0.7 part of 2-acrylamide-2-methylpropanesulfonic acid acrylic acid copolymer AA/AMPS, 1.5 parts Dissolve styrene-butadiene latex and 0.5 parts of simethicone in 44 parts of water to prepare an aqueous solution, put the aqueous solution in a high-speed stirrer, turn the stirrer at a low speed (4000±200 rpm), and add it within 15 seconds 100 parts of hydraulic cementitious material, and then continue stirring for 35 seconds under high-speed (12000±500 rpm) rotation to obtain a high-temperature-resistant and acid-soluble oil well cement slurry system.

Example 5

It is produced by dry method, crushing 100 parts of limestone, 15 parts of clay, 3 parts of hematite, 3 parts of diatomaceous earth, and 1.5 parts of phosphogypsum into lumps with a particle size of less than 25mm, mixed and sent to the rotary kiln for calcination 1h, calcination temperature 1350～1450℃, enter into the cooling machine for cooling, rapid cooling to 62℃, cooling rate 18～20℃/min, then add 1 part of gypsum, 35 parts of silicon powder, 50 parts of iron ore powder, 30 parts of calcium carbonate Grinding is carried out after mixing, so that the particle size of the product is controlled at 1-100 μm, and a high-temperature-resistant and acid-soluble hydraulic gelling material is obtained.

Weigh 1.5 parts of sodium polystyrene sulfonate, 6 parts of 2-acrylamide-2-methylpropanesulfonic acid AMPS, 0.8 parts of 2-acrylamide-2-methylpropanesulfonic acid acrylic acid copolymer AA/AMPS, 1.5 parts Dissolve styrene-butadiene latex and 0.5 parts of simethicone in 48 parts of water to prepare an aqueous solution, put the aqueous solution in a high-speed stirrer, turn the stirrer at a low speed (4000±200 rpm), and add it within 15 seconds 100 parts of hydraulic cementitious material, and then continue stirring for 35 seconds under high-speed (12000±500 rpm) rotation to obtain a high-temperature-resistant and acid-soluble oil well cement slurry system.

2. Performance test of oil well cement slurry system prepared by high temperature resistant and acid soluble hydraulic cementitious material

1. Application performance test of oil well cement slurry

According to the oil well cement standard GB/T19139-2012 "Oil well cement test method", the application performance test of the high temperature resistant hydraulic acid soluble gelling system is carried out. The test results are shown in Table 1.

Table 1 Test results of application performance of oil well cement slurry

It can be seen from the performance test results that the slurry density is adjustable from 1.60 to 2.20g/cm ³ , the water loss performance is low, the high temperature settlement stability is good, the fluidity is moderate, and the thickening time is linearly adjustable, which basically meets the needs of on-site construction. Require.

Figure 1 shows the results of the thickening experiment of Example 3, and the experimental conditions are 130°C and 50MPa. Experimental results: The thickening time is 272 minutes, the transition time is 5 minutes, close to right-angle thickening, the slurry performance is good, the expected effect is achieved, and the engineering application is satisfied.

2. Compressive strength test of hardened body

Table 2 shows the compressive strength test results of the examples under the conditions of 130°C and 20MPa water bath curing.

The compressive strength test result of table 2 hardened body

The compressive strength of the hardened body of the oil well cement slurry prepared by the present invention is still stable at a high temperature of 130°C, no strength decline appears after 60 days of curing, and the overall strength performance is stable; in contrast, the hardened body cured by G-grade cement paste , after 3 days of curing, there is a more obvious strength decline, and the hardened body has gradually lost its structural strength.

3. Acid solubility test of hardened body

(1) Using the residual mass method, soak the hardened body in 10% hydrochloric acid for 2 hours, and test its acid solubility within 2 hours.

Table 3 shows the results of the 2h acid dissolution experiment of the hardened body with a curing age of 3d at 130°C in 10% sufficient hydrochloric acid.

Table 3 Acid solubility test results of hardened body

It is found by the acid dissolution experiment that the acid solubility rate of the hardened body of the present invention can reach up to 84.7% in 2 hours, wherein the high density system is affected by the weighting agent, and the acid solubility rate performance is slightly lower; in contrast, the G grade cement slurry The acid-soluble rate of the hardened body is only 50.5%, so it can be seen that the hardened body formed by curing the oil well cement slurry with the cementitious material of the present invention has relatively excellent acid-soluble properties.

(2) Choose these 6 time points of 20min, 40min, 60min, 80min, 100min, 120min, carry out the real-time acid-soluble rate test to the hardened body of G grade cement paste and the hardened body (embodiment 3) of the present invention, experimental result See Figure 2.

The results show that the reaction rate of the hardened body of G-grade cement paste is always relatively slow, and the final acid-soluble rate is only 50.5% in 2 hours; while the reaction rate of the hardened body of Example 3 is accelerated sharply at 20-60 minutes, and the reaction rate is slowed down at 60-80 minutes , The reaction gradually stopped after 80-120 minutes, and the final acid-dissolution rate was 84.7% in 2 hours. While ensuring the plugging quality, the acid-dissolution effect was greatly improved.

Claims (3)

1. the oil-well cement slurry system of the molten hydraulic cementing materials of theobromine containing high temperature resistant, the oil-well cement slurry system is by following Each component forms by weight:

The cementitious material is made of by weight following each component:

2. oil-well cement slurry system as described in claim 1, which is characterized in that CaCO in the lime stone₃Purity be at least 65%, SiO in the clay₂Content be not less than 60%, Fe in the bloodstone₂O₃Content be 50%~70%.

3. oil-well cement slurry system as described in claim 1, which is characterized in that the silicon powder is the particle of 400 mesh, the carbon Sour calcium is the different-grain diameter mixture of two kind of 1500 mesh and 10000 mesh.