An oil-resistant fireproof plate material for compact oil and gas combustion pool and a construction method thereof

Abstract

The application provides an oil-resistant refractory plate for a dense oil and gas combustion pool and a construction method thereof, and belongs to the technical field of industrial furnace construction and building industry. The oil-resistant refractory plate comprises 20-25% of alumina micropowder, 45-50% of 72-m type alumina fiber, 20-25% of quartz powder, 4-6% of a binder, 2-3% of a water repellent agent and 2-3% of a corrosion inhibitor, and the plate has a compressive strength of 2.2±0.3 MPa, a flexural strength of 3±0.6 MPa, a density of 420±60 kg / m 3 , and a refractoriness of greater than or equal to 1700 DEG C. In addition, the plate is matched with a specific construction method, such as that the blowout cylinder is horizontally translated by 2 m for centering when considering the inertia of the gas flow, and the plate is installed in two directions, and the like, so that the technical blank of the blowout technology of the dense oil and gas combustion pool is filled, and the technical problem of the dense gas block combustion pool burning and melting is solved, so as to meet the actual demand.

Description

Technical Field

[0001] This invention relates to an oil-resistant refractory plate for dense oil and gas combustion tanks and its construction method, belonging to the comprehensive technical field of industrial furnace construction and building industry. Background Technology

[0002] During oil and gas extraction, after the well testing team completes the testing, a venting operation is required. Venting, in oil and gas exploration and development, is the process of artificially opening the wellhead to allow oil and gas to be released from the well in a controlled manner for oil and gas testing. Its purpose is to test the underground natural gas pressure and release the collected natural gas through pipelines for combustion.

[0003] During natural gas extraction and venting in the Sichuan-Chongqing region, semi-enclosed masonry or reinforced concrete structures are used to limit the combustion area and protect the ecological environment. Currently, shale bricks are commonly used as the masonry material for combustion pits. Although shale bricks have a certain degree of temperature resistance, large-scale melting will occur when exposed to temperatures above 1100℃ for extended periods.

[0004] Tight gas refers to natural gas in sandstone formations with a permeability of less than 0.1 mD. It is an important unconventional natural gas resource, mainly distributed in the Sichuan Basin in China. The characteristics of tight gas block venting include: long venting time, numerous venting events, and the ejection of large amounts of condensate oil. Under the action of high-pressure natural gas and acidic liquids, the high temperature generated by venting ignition causes severe melting of firewalls; simultaneously, it leaves solid residues in the combustion pool, which are difficult to remove, increasing the difficulty of reclaiming the combustion pool. Furthermore, damage to the combustion pool not only affects the efficiency of oil testing but also causes serious pollution to the local environment.

[0005] Traditional refractory materials are generally used in industrial furnace construction and are divided into unshaped refractories and shaped refractories, among which: I. Unshaped refractories, including refractory castables, sprayables, and ramming mixes, are all semi-finished materials that need to be shaped during construction and undergo a special heat treatment process—furnace drying—in an enclosed space to achieve their refractory properties. Since the petroleum industry's blowout processes are outdoors and lack furnace drying processes, unshaped refractories are not suitable for blowout operation environments. II. Standardized refractory materials, including refractory bricks, refractory blocks, and refractory boards, are all finished products that can be directly laid and installed on-site. However, the blowout cylinders for the blowout process come in different forms, such as front-end blowout and side-end blowout. Refractory bricks and blocks require mortar for laying, have a long curing period, and because the blowout cylinder form cannot be determined during construction, a full lining must be laid as a protective layer, resulting in high costs and non-recyclability. In contrast, refractory boards are the most suitable standardized refractory materials for blowout operations, as their lightweight, easy installation, and recyclability are well-suited to the blowout environment. However, existing refractory boards are mostly used in indoor environments, generally possessing high-temperature resistance, but with poor water resistance, abrasion resistance, and weather resistance, and are generally not used in outdoor environments.

[0006] Although the prior art CN118684509A discloses "a method for preparing a composite fiber toughened refractory material", the steps include: preparing primary composite fibers, preparing secondary composite fibers, surface pre-modification, hyperbranching modification, and mixing and sintering. The mixing and sintering method involves mixing alumina powder, silica powder, calcium oxide, magnesium oxide, titanium oxide, carboxymethyl cellulose, and hyperbranched modified fibers evenly, and then dry pressing to obtain a green body. Although it involves shaped refractory materials, they are mostly used indoors (e.g., as linings for industrial kilns). They have high refractoriness but poor weather resistance. In outdoor environments exposed to sun and rain, their quality will inevitably be reduced, making them unsuitable for open-air venting and spraying environments in the petroleum industry. CN102515672A discloses "a mortar for building firewalls in the petroleum industry and its construction process", and CN102924105A discloses "silicate cement refractory mortar and its construction process". These mainly involve unshaped refractory materials, which have great limitations in the use of tight oil and gas blocks, such as: 1. They all need to be processed into finished products on site, but once formed on site, they are irreversible and cannot be recycled, resulting in high costs; 2. The mortar surface is rough and porous, and during venting, the sprayed condensate oil easily adheres to its surface, preventing heat exchange and causing the material to be burned at excessively high temperatures.

[0007] Therefore, there is a need for a refractory board that is high-performance, easy to install, suitable for outdoor environments, and used in dense oil and gas combustion tanks. Summary of the Invention

[0008] This invention addresses the problems of oil-resistant and refractory materials during blowouts in existing oil and gas extraction processes by proposing an oil-resistant and refractory board for tight oil and gas combustion pools and its construction method. This technical solution fills the technological gap in blowout prevention for combustion pools in tight gas blocks, solves the technical problem of combustion pool melting in tight gas blocks, and improves the wall material of the combustion pool to meet practical needs.

[0009] To achieve the above technical objectives, the following technical solution is proposed: The primary objective of this technical solution is to provide an oil-resistant and fire-resistant board for use in a dense oil and gas combustion tank, comprising the following components by weight percentage: 20-25% alumina micro powder, 45-50% 72-m type alumina fiber, 20-25% quartz powder, 4-6% binder, 2-3% water-repellent agent, and 2-3% corrosion inhibitor. The finished product specifications of the oil-resistant and fire-resistant board include: compressive strength 2.2±0.3MPa, flexural strength 3±0.6MPa, and density 420±60kg / m³. 3 The refractoriness is ≥1700℃. The relevant standards include: *Refractory Fibers and Products* (GB / T3003-2017), *Test Methods for Refractory Fiber Products* (GB / T 17911-2018), *Test Methods for Refractoriness of Refractory Materials* (GB / T 7322-2017), *Test Methods for Thermal Shock Resistance of Refractory Materials* (GB / T 30873-2014), *Test Methods for Flexural Strength of Refractory Materials at Room Temperature* (GB / T 3001-2017), *Test Methods for Compressive Strength of Refractory Materials at Room Temperature* (GB / T 5072-2008), and *Test Methods for Permanent Linear Change of Refractory Materials under Heating* (GB / T 5988-2007).

[0010] The alumina micro powder comprises 75-85% alumina micro powder with a particle size of 1-10 μm and 15-25% alumina micro powder with a particle size of 30-50 μm; the Al2O3 content in the alumina micro powder is ≥98%. Limiting the particle size of the alumina micro powder ensures easy and uniform mixing while improving compressive strength (too fine a powder results in poor compressive strength); limiting the Al2O3 content in the alumina micro powder ensures sufficient aluminum content, thereby giving the sheet higher refractoriness. The 72-m type alumina fiber has a diameter of 0.05 mm and a length of 10–13 mm; the Al2O3 content in the 72-m type alumina fiber is ≥70%. Using this 72-m type alumina fiber ensures refractoriness while improving economic efficiency. The quartz powder comprises 55-65% quartz powder with a particle size of 0.5-1 mm and 15-25% quartz powder with a particle size of 200 mesh; the SiO2 content in the quartz powder is ≥99%; The adhesive is an aqueous solution of polyacrylate with a concentration of 4-6 wt%; The water-repellent agent is methylsiloxane or polysiloxane (which is a water-based emulsion). The corrosion inhibitor is γ-glycidoxypropyltrimethoxysilane (KH-560) at a concentration of 1.5–2.5 wt%. When using it, a mixed solvent of ethanol and water (9:1) is prepared to pre-hydrolyze the γ-glycidoxypropyltrimethoxysilane. This agent improves the interfacial compatibility, hydrophobicity, and durability of polymer composites. If the concentration is too low, the desired technical effect will not be achieved, and the substrate will be easily damaged by rain; if the concentration is too high, it is uneconomical.

[0011] The second objective of this technical solution is: a method for preparing an oil-resistant refractory plate for a tight oil and gas combustion tank, comprising the following steps: S1: Crush alumina micro powder, 72-m type alumina fiber and quartz powder into fine powder of 200 mesh or more; S2: Add the emulsified water-repellent agent, the pre-hydrolyzed corrosion inhibitor and the binder aqueous solution in sequence, and forcibly stir at 500-800 r / min at room temperature (25±5℃) to obtain a uniform slurry with no lumps and good fluidity; S3: The blank is formed by pressing with a hydraulic press at a pressure of 50-80MPa for 3-5 minutes. The density of the blank after pressing is ≥0.8g / cm³ and there are no cracks on the surface. S4: Dry in an oven at 80–100℃ for 24–48 hours, with a moisture content ≤1.5% after drying; S5: Then, fire in a kiln at 1450-1550℃ for 2-4 hours until sintering is complete, with a bulk density ≥0.35g / cm³ and porosity ≤15%; S6: Use a belt grinder to grind the surface at a speed of 2000-3000 r / min. The surface roughness Ra after grinding is ≤3.2μm, smooth and burr-free. S7: CNC cutting machine is used to cut the material at room temperature using water cooling to the required size (generally 1200*600*50mm is used on site). The dimensional deviation after cutting is ≤±1mm, and there are no chips or defects on the edges, thus obtaining the oil-resistant and fire-resistant board.

[0012] The third objective of this technical solution is: a construction method for oil-resistant and fire-resistant panels used in tight oil and gas combustion tanks, using equipment including expansion bolts, dry-hanging fasteners, and an impact drill, specifically including the following steps: S1 Wall Leveling: Clean and level the wall surface to be treated, and mortar plastering is strictly prohibited on this wall surface; S2 Fire-resistant Board Installation: Use dry hanging or anchoring methods to fix the four corners of the oil-resistant fire-resistant board to the wall surface treated in step S1. When the venting nozzle is a front-end venting nozzle, refractory boards are installed on the rear wall and the two side wing walls, with an installation length of 3 to 5 meters on each side wing wall. This length limit ensures effective coverage of the boards while saving material. For example, if it is less than 3 meters, the uncovered parts of the boards may melt; if it is greater than 5 meters, the amount of boards used will increase, resulting in higher costs. When the venting pipe is a two-sided venting system, refractory boards are installed on the two side wing walls, with each side wing wall having an installation length of 6 to 10 meters. This length limit ensures effective coverage of the boards while saving material. For example, if it is less than 6 meters, the uncovered parts of the boards may melt; if it is greater than 10 meters, the amount of boards used will increase, resulting in higher costs. Among them, expansion bolts or dry-hanging fasteners made of stainless steel 304 or higher are used to ensure its fire resistance; as a preferred option, the fire-resistant boards are installed horizontally to prevent the fire-resistant boards from warping. S3 venting nozzle placement: Considering the inertia of the airflow during venting, the venting nozzle should be moved forward 1-3m to center, and installed in both the front and rear directions.

[0013] The beneficial technical effects of adopting this technical solution are as follows: This invention achieves optimized raw material proportions and a tightly packed finished product structure by precisely adjusting the types, ratios, and particle sizes of raw materials such as alumina micro powder, alumina fiber, quartz powder, binder, water-repellent agent, and corrosion inhibitor, thus proposing an oil-resistant refractory board. Secondly, it provides a construction method suitable for dense oil and gas combustion tanks, improving the overall refractoriness of the combustion tank and extending its service life. Details are as follows: I. In this invention, the oil release test is conducted in a high-temperature, high-pressure environment, with the pressure at the release nozzle typically ranging from 3 to 5 MPa. The high-pressure gas mixes with underground liquids and fine solid particles from the ground, resulting in a severe fluid erosion effect on the combustion pool structure. The optimized proportions of alumina micro-powder, alumina fiber, and quartz powder in the raw materials provide the refractory board with superior strength, rigidity, and wear resistance. As a protective layer, it effectively enhances the structure's resistance to fluid erosion. Second, in this invention, the refractory boards can be installed by dry hanging or anchoring, making installation convenient and flexible. Since the oil testing team needs to enter the site after the pre-drilling engineering is completed, and the type of the blowout pipe is unknown during the pre-drilling engineering, using refractory bricks, refractory mortar, or other materials as a protective layer requires simultaneous construction with the combustion pool, necessitating full lining. However, using this refractory board, after the oil testing team arrives and installs the blowout pipe, the refractory board can be placed on the wall to be protected according to the type of blowout pipe, eliminating the need for full lining and effectively saving costs. Third, in this invention, the binder, water-repellent agent and corrosion inhibitor have fire resistance and chemical resistance, are suitable for use under extreme high temperature conditions, have excellent thermal stability and thermal shock resistance, and as a protective layer, their fire resistance is as high as 1700°C or more, which can effectively isolate high temperature, improve structural fire resistance, and effectively protect the wall and prevent melting. Fourth, in this invention, the addition of silane-based materials (corrosion inhibitors) forms a waterproof and hydrophobic film on the surface of the refractory board, making the surface of the material dense and smooth, effectively reducing the penetration of liquids, preventing the corrosion of acidic compounds such as condensate oil and acid liquid, and thus preventing the condensate oil from adhering and burning, causing the wall to melt; at the same time, it can effectively reduce the erosive effect of rainwater, improve the weather resistance of the protective layer, and extend the service life, making it particularly suitable for long-term outdoor working environments; V. In this invention, the refractory board is an industrial finished product that can be used immediately after installation without a curing period. When the amount of venting gas is particularly large, or when the venting pipeline installation angle is off or the wind direction is affected, the firewall may suffer particularly severe localized burning. Using this refractory board, repairs can be carried out directly during the venting interval; while using refractory bricks or refractory mortar, a 28-day curing period is required. That is, under venting conditions, this refractory board is particularly suitable for emergency response. VI. The refractory boards involved are reusable, improving resource utilization and reducing environmental impact. In actual gas release operations, the gas production of each well varies, with some producing over 500,000 m³ per day. 3 High-yield wells also have daily production below 1000m³. 3 Low-yield wells, and even some individual wells, may abandon venting due to lack of test pressure. The duration and volume of venting affect the service life of refractory panels. Under normal circumstances, the longer the venting time and the larger the venting volume, the shorter the panel life and the lower the panel recovery rate. When low-yield wells occur, the installed refractory panels can generally be completely disassembled and reused. Attached Figure Description

[0014] Figure 1 This is a photograph of the oil-resistant and fire-resistant sheet material product of this invention. Figure 2 This is a photograph of the actual installation state of the oil-resistant and fire-resistant board in this invention (front-end spraying, oil-resistant and fire-resistant board installed on the rear wall, oil-resistant and fire-resistant board not yet installed on the side wing walls). Figure 3 This is a photograph of the actual installation state of the oil-resistant and fire-resistant board in this invention (spraying on both sides, with the oil-resistant and fire-resistant board installed on both wing walls). Figure 4 This is the first test report related to the oil-resistant and fire-resistant sheet material in Embodiment 1 of the present invention. Figure 5 This is the second test report related to the oil-resistant and fire-resistant sheet material in Embodiment 1 of the present invention. Figure 6 This is a schematic diagram of the theoretical spray pattern from the nozzle. Figure 7 This is a schematic diagram of the actual spraying action of the spray nozzle; Figure 8 This is a schematic diagram of the combustion tank involved in the application example. Detailed Implementation

[0015] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0016] Currently, conventional refractory boards are mainly used in metallurgical or industrial kilns, often in enclosed spaces, with a focus on refractoriness and thermal shock resistance. However, refractory boards used in blowout operations not only need increased compressive strength to withstand the impact of blowout gases, but also increased abrasion resistance to resist the erosion of the blowout gas stream, and enhanced weather resistance for outdoor use, resisting damage from sun and rain, among other things.

[0017] Therefore, the following examples illustrate this.

[0018] In the following embodiments, all raw material components involved were purchased commercially, and the refractory board testing methods involved include "refractory material refractoriness test method", "refractory material stress-strain test method (three-point bending method)", "refractory material room temperature compressive strength / flexural strength test method", and "refractory material heating permanent linear change test method". The testing equipment involved includes: electric thermostatic drying oven, high temperature re-firing test furnace, hydraulic press, thermal conductivity meter, etc. The standards used include: Refractory Fibers and Products (GB / T 3003-2017), Refractory Fiber Products Test Methods (GB / T 17911-2018), Refractory Materials Refractoriness Test Methods (GB / T 7322-2017), Refractory Materials Thermal Shock Resistance Test Methods (GB / T 30873-2014), Refractory Materials Flexural Strength Test Methods at Room Temperature (GB / T 3001-2017), Refractory Materials Compressive Strength Test Methods at Room Temperature (GB / T 5072-2008), and Refractory Materials Permanent Linear Change Test Methods (GB / T 5988-2007).

[0019] Example 1 This embodiment provides: an oil-resistant and fire-resistant plate for a dense oil and gas combustion tank, comprising, by weight: 67g alumina micro powder, 120g 72-m type alumina fiber, 67g quartz powder, 13g 4wt% polyacrylate aqueous solution, 5g polysiloxane, and 5g 2wt% γ-glycidyl etheroxypropyltrimethoxysilane. The finished product specifications of oil-resistant and fire-resistant boards are shown in Table 1 below. Figure 4-5 As shown.

[0020] Example 2 This embodiment provides: an oil-resistant and fire-resistant board for a dense oil and gas combustion tank, comprising, by weight: 60g of alumina micro powder, 150g of 72-m type alumina fiber, 60g of quartz powder, 15g of a 4wt% polyacrylate aqueous solution, 6g of polysiloxane, and 6g of 2wt% γ-glycidyl etheroxypropyltrimethoxysilane. The finished product specifications of oil-resistant and fire-resistant boards are shown in Table 1 below.

[0021] Example 3 This embodiment provides: an oil-resistant and fire-resistant board for a dense oil and gas combustion tank, comprising, by weight: 68g of alumina micro powder, 160g of 72-m type alumina fiber, 40g of quartz powder, 15g of a 4wt% polyacrylate aqueous solution, 6g of polysiloxane, and 6g of 2wt% γ-glycidyl etheroxypropyltrimethoxysilane; The finished product specifications of oil-resistant and fire-resistant boards are shown in Table 1 below.

[0022] Example 4 The second objective of this technical solution is: a method for preparing an oil-resistant refractory plate for a tight oil and gas combustion tank, comprising the following steps: S1: Crush alumina micro powder, 72-m type alumina fiber and quartz powder into fine powder of 200 mesh or more; S2: Add the emulsified water-repellent agent, the pre-hydrolyzed corrosion inhibitor and the binder aqueous solution in sequence, and forcibly stir at 500-800 r / min at room temperature (25±5℃) to obtain a uniform slurry with no lumps and good fluidity; S3: The blank is formed by pressing with a hydraulic press at a pressure of 50-80MPa for 3-5 minutes. The density of the blank after pressing is ≥0.8g / cm³ and there are no cracks on the surface. S4: Dry in an oven at 80–100℃ for 24–48 hours, with a moisture content ≤1.5% after drying; S5: Then, fire in a kiln at 1450-1550℃ for 2-4 hours until sintering is complete, with a bulk density ≥0.35g / cm³ and porosity ≤15%; S6: Use a belt grinder to grind the surface at a speed of 2000-3000 r / min. The surface roughness Ra after grinding is ≤3.2μm, smooth and burr-free. S7: CNC cutting machine is used for water-cooling cutting at room temperature to produce the required dimensions (typically 1200*600*50mm on-site). The dimensional deviation after cutting is ≤±1mm, and there are no chips or defects at the edges, thus obtaining oil-resistant and fire-resistant boards (such as...). Figure 1 (As shown).

[0023] Example 5 Based on Examples 1-3, this example provides: a construction method for oil-resistant refractory panels for tight oil and gas combustion tanks, using equipment including expansion bolts, dry-hanging fasteners, and an impact drill, specifically including the following steps: S1 Wall Leveling: Clean and level the wall surface to be treated, and mortar plastering is strictly prohibited on this wall surface; S2 Fire-resistant Board Installation: Use dry hanging or anchoring methods to fix the four corners of the oil-resistant fire-resistant board to the wall surface treated in step S1. When the blowout nozzle is a front-end blowout type, the refractory panels are installed on the rear wall and the two side wing walls, with each side wing wall having an installation length of 3-5m (e.g., Figure 2 (as shown) When the blowdown nozzle has two sides, the refractory panels are installed on the two side wing walls, with each side wing wall having an installation length of 6-10m (e.g., Figure 3 (as shown) Among them, expansion bolts or dry-hanging fasteners made of stainless steel 304 or higher are used to ensure its fire resistance; as a preferred option, the fire-resistant boards are installed horizontally to prevent the fire-resistant boards from warping. S3 discharge nozzle placement: Considering the inertia of the airflow during discharge, the discharge nozzle should be moved forward 1-3m to center and installed in both the front and rear directions. When the blowout nozzle has two sides, the drilling team may not fix the front and rear positions of the nozzle during installation; it might extend 3m or 5m into the wall. Theoretically, the vented gas should be evenly sprayed onto the wall surface (e.g., Figure 6 As shown), the installation sequence of the panels is as follows: starting from point O in the venting cylinder, align with points A and B on the wall, and then install the panels on both the front and rear sides respectively. However, in reality, the vented gas has inertia, and during actual venting, the fire-exposed area of ​​the wall (such as...) Figure 7 As shown, it is further forward than the left side. Therefore, in summary, the position of the spray nozzle is moved forward by 1 to 3 meters to center it, and the panels are installed in both the front and back directions. This ensures effective coverage while saving panels and reducing the melting of panels / walls.

[0024] Comparative Example 1 This comparative example compares the performance of commercially available refractory boards (1400 type high-alumina fireproof board produced by Shandong Luyang Energy-Saving Materials Co., Ltd., certificate number J2023-08-20-1) with the refractory boards involved in Examples 1-3. Specifically, the following tests were conducted: Test Methods for Refractory Fiber Products (GB / T 17911-2018), Test Methods for Refractoriness of Refractory Materials (GB / T7322-2017), Test Methods for Thermal Shock Resistance of Refractory Materials (GB / T 30873-2014), Test Methods for Flexural Strength of Refractory Materials at Room Temperature (GB / T 3001-2017), Test Methods for Compressive Strength of Refractory Materials at Room Temperature (GB / T 5072-2008), and Test Methods for Permanent Linear Change of Refractory Materials under Heating (GB / T 5988-2007). The results are shown in Table 1 below.

[0025] Table 1 It can be seen that the refractory board involved in this invention has 3 times the flexural strength, 2 times the compressive strength, and superior fire resistance compared to commercially available refractory boards. Its corrosion inhibition rate reaches more than 90%, and its acid resistance is excellent, making it suitable for use in blowdown operations.

[0026] Comparative Example 2 Based on Example 1, the difference between this comparative example and Example 1 is that a 4 wt% aqueous polyacrylate binder is not used; otherwise, the results are the same as in Example 1. The results are shown in Table 2.

[0027] Comparative Example 3 Based on Example 1, the difference between this comparative example and Example 1 is that the hydrophobic agent polysiloxane water-based emulsion is not used; otherwise, it is the same as Example 1. The results are shown in Table 2.

[0028] Comparative Example 4 Based on Example 1, the difference between this comparative example and Example 1 is that 2 wt% of the γ-glycidoxypropyltrimethoxysilane (KH-560) corrosion inhibitor was not used; otherwise, the results were the same as in Example 1. The results are shown in Table 2.

[0029] Table 2 Therefore, it can be concluded that: 1. In the production of this refractory board, the binder (polyacrylate aqueous solution) is the core of the material's molding and mechanical properties. Its absence will result in the material being unable to be molded, and its refractoriness and strength will decrease significantly. 2. In the production of this refractory board, the hydrophobic agent (polysiloxane) significantly affects the flexural / compressive strength and post-firing stability, and its hydrophobic effect reduces water penetration and improves the durability of the material; 3. In the production of this refractory board, the corrosion inhibitor (KH-560) contributes greatly to the corrosion inhibition rate. It effectively resists chemical erosion by forming a film on the surface, but has little impact on mechanical properties. 4. For Comparative Example 2, since no adhesive-polyacrylate solution was used, the slurry could not be formed, and therefore the strength, corrosion inhibition rate, bulk density and linear change rate after firing could not be tested. Therefore, the combination of "20-25% alumina micro powder, 45-50% 72-m type alumina fiber, 20-25% quartz powder, 4-6% binder, 2-3% water repellent and 2-3% corrosion inhibitor" effectively ensures the performance of this refractory board to meet the requirements of blowout operations.

[0030] Application examples Based on Example 1, the oil-resistant refractory board involved in this invention is applied to a combustion tank (e.g., Figure 8 (as shown), to further illustrate the invention.

[0031] The application site is located in Santai County (Jinqian 816 well). The combustion pool is situated halfway up a mountain, with its opening facing the slope. It is surrounded by soil filler, and the surrounding vegetation has been cleared. Cameras and warning lines are installed at the site. According to weather forecasts, there will be no rain in the coming week, ensuring a favorable testing environment. The combustion pool is a type of combustion pool, with an internal length of 12m, a width of 4.75m, and is divided into three layers, each 1m high, for a total height of 3m (e.g., Figure 8 (As shown). After verifying the discharge direction with the on-site construction team, it was determined that this was a two-sided discharge, with the flames mainly concentrated on the two wings. Therefore, 20m nozzles were installed on each wing of the combustion pool. 2 Oil-resistant and fire-resistant boards; For oil-resistant and fire-resistant boards, two different installation methods were used in this application. The bottom row used an adhesive and screw anchoring method, that is, the adhesive was applied to the back of the board and then it was pressed tightly against the wall. Expansion screws were driven into the wall through the board, one screw on each side. Finally, high-temperature adhesive was applied to the surface of the screws. The second and third rows used an adhesive and steel fastener fixing method, that is, the I-beams were first driven into the wall with expansion screws, then the board was embedded between two steel fasteners, and finally, high-temperature adhesive was applied to the surface of the fasteners.

[0032] I. From September 23 to October 1, 2023, the Jinqian 816 well experienced intermittent blowout for a total of 7 days, with a production of 520,000 m³. 3 The test pressure was 16 MPa. After the burst, the fire-facing side of the firewall was not exposed to flame, the oil-resistant and fire-resistant panels on both sides did not fall off, and the combustion pool structure remained intact without any cracks. In this instance, the oil-resistant refractory panels were installed correctly, directly facing the vent, with the flames mainly concentrated in the rear section. Based on the color changes of the oil-resistant refractory panels, it can be seen that some panels in contact with the flames bent or deformed. However, 80% of the panels did not bend or deform and can be removed and reused. Slightly bent panels can also be placed outside the combustion chamber for future use, resulting in a reuse rate exceeding 95%. The stainless steel components used for anchoring showed some surface flaking, but the screws did not melt and did not affect the removal of the panels.

[0033] II. From December 20th to December 26th, 2023, the Jinqian 816 well underwent its second blowout, lasting 6 days, with a production of 650,000 m³. 3 The test pressure was 18 MPa. After the release, the oil-resistant refractory panels were not damaged, but the oil-resistant refractory panels on the inner side of the firewall showed obvious warping. This was because the second release had a larger air volume and an additional release pipeline was added to the right side, causing significant melting and thinning of the cross-section of the uncovered oil-resistant refractory panels on the right wall. At the covered areas, the combustion pool structure remained intact, the cross-section did not thin, and no cracks were generated.

[0034] 1. Therefore, it can be concluded that the oil-resistant refractory board is incorrectly fixed. The oil-resistant refractory board in this well is fixed at the waist. Although it can fix the oil-resistant refractory board to the wall, it will cause the oil-resistant refractory board to warp due to heat. It should be fixed at the four corners. 2. When installing the oil-resistant refractory plate in this well, the centering was based on the position of the blowout pipe, but the inertia of the blowout gas was not taken into account. The installation position of the oil-resistant refractory plate should be shifted 2m along the direction of the gas flow. 3. On the fire-exposed part of the right wing wall, obvious melting and thinning of the cross-section were observed in the areas not covered by the oil-resistant and fire-resistant boards, indicating that the oil-resistant and fire-resistant boards have a significant fire protection effect on the wall.

[0035] The principle behind this oil-resistant refractory board is that its dense and smooth surface effectively prevents condensate oil adhesion. Specifically, this invention increases the proportion of raw materials by adding 20-25% quartz powder. Quartz powder, with its stable chemical properties, acts as aggregate in the structure, significantly improving the density of the structure during hydraulic molding, thus ensuring a dense surface for the oil-resistant refractory board. Furthermore, the specific formula of this invention ensures a high hardness of the green body structure, allowing for smooth polishing. Under specific polishing conditions, the surface of the oil-resistant refractory board remains smooth, ultimately ensuring good performance and compatibility with blowdown operations. In contrast, existing shale brick walls and mortar joints have a rough, porous structure that cannot be polished smooth, facilitating condensate oil adhesion and causing the wall to melt.

[0036] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Any simple modifications or equivalent changes made to the above embodiments based on the technical essence of the present invention shall fall within the protection scope of the present invention.

Claims

1. An oil-resistant and refractory board for a tight oil and gas combustion tank, characterized in that, By weight percentage, it comprises the following components: 20-25% alumina micro powder, 45-50% 72-m type alumina fiber, 20-25% quartz powder, 4-6% binder, 2-3% water repellent and 2-3% corrosion inhibitor. The finished product specifications of the oil-resistant and fire-resistant board include: compressive strength 2.2±0.3MPa, flexural strength 3±0.6MPa, and density 420±60kg / m³. 3 Refractory resistance ≥1700℃.

2. The oil-resistant and refractory plate for a tight oil and gas combustion tank according to claim 1, characterized in that, The alumina micro powder comprises 75-85% alumina micro powder with a particle size of 1-10 μm and 15-25% alumina micro powder with a particle size of 30-50 μm; the content of Al2O3 in the alumina micro powder is ≥98%.

3. The oil-resistant and refractory plate for a tight oil and gas combustion tank according to claim 1, characterized in that, The 72-m type alumina fiber has a diameter of 0.05 mm and a length of 10-13 mm; the Al2O3 content in the 72-m type alumina fiber is ≥70%.

4. The oil-resistant and refractory plate for a tight oil and gas combustion tank according to claim 1, characterized in that, The quartz powder comprises 55-65% quartz powder with a particle size of 0.5-1 mm and 15-25% quartz powder with a particle size of 200 mesh; the SiO2 content in the quartz powder is ≥99%.

5. The oil-resistant and refractory plate for a tight oil and gas combustion tank according to claim 1, characterized in that, The adhesive is an aqueous solution of polyacrylate with a concentration of 4-6 wt%.

6. The oil-resistant and refractory plate for a tight oil and gas combustion tank according to claim 1, characterized in that, The hydrophobic agent is a water-based emulsion of methylsiloxane or a water-based emulsion of polysiloxane.

7. The oil-resistant and refractory plate for a tight oil and gas combustion tank according to claim 1, characterized in that, The corrosion inhibitor is γ-glycidoxypropyltrimethoxysilane at a concentration of 1.5–2.5 wt%.

8. The oil-resistant and refractory plate for a tight oil and gas combustion tank according to any one of claims 1-7, characterized in that, The preparation method of the oil-resistant and fire-resistant board includes: S1: Crush alumina micro powder, 72-m type alumina fiber and quartz powder into fine powder of 200 mesh or higher; S2: Add the emulsified water-repellent agent, the pre-hydrolyzed corrosion inhibitor and the binder aqueous solution in sequence, and stir until the mixture is uniform to obtain the slurry; S3: A hydraulic press is used to press the slurry into a blank, controlling the density of the blank to be ≥0.8g / cm³, and the surface to be free of cracks; S4: Dry the green body to a moisture content ≤1.5%; S5: Firing the green body, controlling the bulk density of the green body after firing to be ≥0.35g / cm³ and the porosity to be ≤15%; S6: Use a belt grinder to grind the surface of the fired blank to a surface roughness Ra≤3.2μm, smooth and burr-free; S7: CNC cutting machine is used for water-cooled cutting to control the edges of the board without chipping, thus obtaining oil-resistant and fire-resistant board.

9. A construction method for oil-resistant refractory panels used in tight oil and gas combustion tanks, characterized in that, The equipment used includes expansion bolts, dry-hanging fasteners, and an impact drill. The construction method includes the following steps: S1 Wall Leveling: Clean and level the wall surface to be treated, and mortar plastering is strictly prohibited on this wall surface; S2 Fire-resistant Board Installation: Use dry hanging or anchoring methods to fix the four corners of the oil-resistant fire-resistant board to the wall surface treated in step S1. When the blowout nozzle is a front-end blowout, the refractory panels are installed on the rear wall and the two side wing walls, with the installation length on the two side wing walls each accounting for 3 to 5 meters. When the blowout nozzle is a two-sided blowout, the refractory board is installed on the two side wing walls, and the installation length on each side wing wall is 6 to 10m. S3 spray nozzle placement: Move the spray nozzle position forward 1-3m to center it, and install it in both the front and rear directions.

10. The construction method according to claim 9, characterized in that, Expansion bolts and dry-hanging fasteners made of 304 stainless steel are used.

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