Low-density high-temperature-resistant refractory material and application thereof

Abstract

The invention discloses a low-density high-temperature-resistant refractory material which comprises the following components in percentage by mass: 40%-50% of CA70 cement, 10%-18% of CA80 cement, 15%-20% of light mullite and 14%-35% of a binding agent. The refractory material provided by the invention can effectively solve the problems of cracking of a wing wall of a combustion pool and melting of a pool wall during natural gas blowout combustion, completely eradicates potential safety hazards, and meets the long-time blowout process requirements. Meanwhile, due to low density of the material, the material transportation cost can be effectively reduced. Under the condition that the compression strength, the breaking strength, the fire resistance and the stability are met, the refractory material disclosed by the invention is used for manufacturing a standard module and building an assemblable combustion cell, so that the construction period is shortened, the construction efficiency is improved, and the ecological environment is protected. The problems that a traditional combustion cell is long in construction period, large in workload, large in dismantling difficulty, difficult to maintain and the like are solved.

Description

Technical Field

[0001] The invention relates to a low-density high-temperature resistant refractory material and application thereof, belonging to the technical field of refractory materials. Background Art

[0002] As the cleanest fossil energy and an important industrial raw material, natural gas has been exploited and utilized on a large scale. In natural gas exploration and development, in order to conduct oil and gas testing, it is necessary to manually open the wellhead to allow the oil and gas in the well to spray out of the well in a controlled manner, that is, blowout. Natural gas blowout is an indispensable part of exploration and development. In order to avoid the impact of natural gas combustion on the surrounding environment during blowout, according to relevant regulations, the blowout combustion must be confined in a semi-enclosed combustion pool.

[0003] The current combustion pools are mostly built in the way of "laying shale bricks + refractory mortar plastering". The combustion pools with this structure have the following problems in the production and operation process:

[0004] 1) Large transportation volume, large masonry workload and long construction period.

[0005] The dimensions of the common combustion pool for pre-drilling equipment are 13m × 7m × 3.5m in length × width × height (outside dimensions), 0.9m in foundation depth, 1.0m in bottom thickness, 0.6m in top thickness, and 133m in wall and foundation brickwork. 3 , weighing about 240 tons, with a quantity of 68,100. For areas with poor material transportation conditions, the transportation cost of building a burning pool is too high and the construction period will be extended.

[0006] 2) The utilization rate of construction materials is not high. The amount of construction slag after blasting is large and difficult to remove, making it difficult to reclaim the land in the later stage. In addition, the combustion pool is damaged during the blasting test, and the cycle for secondary reconstruction is long and difficult.

[0007] The burning pool is built with mortar masonry. After the spraying is completed, the brick masonry needs to be demolished and the land reclaimed. The traditional burning pool masonry is not easy to dismantle, and it will produce a lot of construction waste, making it difficult to reclaim the land in the later stage.

[0008] 3) There are potential safety risks.

[0009] During the blowdown test, there will be multiple combustions. For the combustion pool built by "laying shale bricks + refractory mortar facing", when the pool wall temperature reaches above 1400℃ during the blowdown process, the wing wall often cracks or part of the pool wall melts. The combustion pool needs to be repaired twice in time to meet the requirements of the subsequent process. Failure to repair in time will cause the acidification return fluid to be unable to be discharged in time, resulting in reservoir pollution, seriously affecting production capacity construction and posing certain safety hazards. Therefore, in order to prevent the pool wall temperature from being too high, the traditional combustion pool can only be blown for a short time, which cannot meet the requirements of long-term blowdown and is inefficient. Summary of the invention

[0010] The present invention provides a low-density high-temperature resistant refractory material, which solves the problems of high material transportation cost and poor high-temperature resistant effect in the prior art.

[0011] To achieve the above-mentioned purpose, the technical solution adopted by the present invention is: a low-density high-temperature resistant refractory material, which, by mass ratio, includes 40% to 50% CA70 cement, 10% to 18% CA80 cement, 15% to 20% lightweight mullite and 14% to 35% binder.

[0012] Preferably, the binder is 80% to 85% phosphoric acid.

[0013] Preferably, the invention further comprises 0-3% silicon powder, 0-3% α-alumina and 0.06%-0.1% explosion-proof fiber.

[0014] Preferably, the explosion-proof fiber is polyethylene fiber.

[0015] Preferably, based on mass ratio, the mixture includes 41% CA70 cement, 18% CA80 cement, 3% silica powder, 3% α-alumina, 20% light mullite, 14.9% phosphoric acid and 0.1% polyethylene fiber.

[0016] Preferably, based on mass, the mixture comprises 50% CA70 cement, 13% CA80 cement, 17% lightweight mullite, 19.9% ​​phosphoric acid and 0.1% polyethylene fiber.

[0017] The present invention provides a method for preparing refractory bricks, which is characterized by comprising the following steps: mixing raw materials according to the above-mentioned mass ratio; after mixing, forming green blanks according to a standardized template, and drying the formed blanks in a natural state; and firing the dried green blanks in a rotary kiln at 1250° C. to obtain refractory bricks.

[0018] The present invention also provides a combustion pool which is obtained by stacking the above-mentioned refractory bricks.

[0019] The refractory material of the present invention can effectively solve the problem of cracking of the combustion pool wing wall and melting of the pool wall during natural gas blasting and combustion, eliminate potential safety hazards, and meet the requirements of long-term blasting process. At the same time, the low density of the material can effectively reduce the material transportation cost.

[0020] Under the conditions of meeting the requirements of compressive strength, flexural strength, fire resistance and stability, the refractory material of the present invention is used to make a standard module to build an assembleable combustion pool, thereby shortening the construction period, improving construction efficiency and protecting the ecological environment. The present invention solves the problems of long construction period, heavy workload, great difficulty in demolition and difficult maintenance of traditional combustion pools. DETAILED DESCRIPTION

[0021] In order to better understand the essence of the present invention, the present invention is further described below in conjunction with specific embodiments.

[0022] The present invention provides a low-density high-temperature resistant refractory material, which comprises, by mass, 40% to 50% of CA70 cement, 10% to 18% of CA80 cement, 15% to 20% of light mullite and 14% to 35% of a binder, wherein the binder is 80% to 85% of phosphoric acid.

[0023] In some embodiments of the present invention, the low-density high-temperature resistant refractory material further comprises 0-3% silicon powder, 0-3% α-alumina and 0.06%-0.1% explosion-proof fiber; the explosion-proof fiber is polyethylene fiber.

[0024] The refractory material of the present invention uses aluminum oxide as the main raw material, is mixed with a small amount of aluminum oxide powder and α-alumina, and is mixed with light mullite and added with a binder and explosion-proof fiber, so that the refractory material can withstand a working temperature of 1500°C, and the density of the refractory material is not more than 1900Kg / m 3 The strength of refractory materials shall not be lower than the relevant indicators of M7.5 cement mortar masonry MU15 bricks in the national standard "Code for Design of Masonry Structures".

[0025] The refractory material of the present invention has the characteristics of low thermal conductivity, low heat capacity and low impurity content. The low thermal conductivity makes the refractory material of the present invention have a good heat insulation effect, which can make the furnace wall thinner; due to its light weight and low thermal conductivity, the refractory material accumulates very little heat energy, and the energy saving effect is very obvious in the intermittent operation kiln; the refractory material of the present invention has a very low content of iron and alkali metal low melts, so it has high refractoriness, and the high aluminum content makes it still maintain good performance in a reducing atmosphere. Therefore, the material of the present invention can also be applied to other high-temperature industrial fields of fire resistance and high temperature resistance.

[0026] The present invention also provides a method for preparing refractory bricks, comprising the following steps:

[0027] The blanks are mixed according to the above mass ratio; after mixing, the blanks are formed according to the standardized template and dried in a natural state; the dried blanks are fired in a rotary kiln at 1250°C to obtain standardized modules that can meet the requirements of the assembled combustion pool; finally, the modules are tested after leaving the kiln and the finished products are marked and put into storage.

[0028] The refractory material preparation process of the present invention is simple and easy to operate. The obtained product can well withstand the high temperature of natural gas blowing and combustion. The manufactured standardized modules can meet the assembly of assembled combustion pools, replacing the traditional "laying shale bricks + refractory mortar plastering" construction method, improving the construction progress, shortening the construction period, avoiding the cracking of the combustion pool wing wall and the melting of the pool wall, and meeting the secondary utilization of construction materials. It is of great significance to reduce the subsequent construction risks and ensure the normal operation of the natural gas extraction project.

[0029] Example 1

[0030] Step 1: According to the above method, select the materials and material ratios (mass percentage) as shown in Table 1.

[0031] Table 1

[0032] Material Ratio CA70 41 CA80 18 Silica powder 3 α-Alumina 3 Lightweight mullite (recycled) 20 80% Phosphoric acid 14.9 Polyethylene explosion-proof fiber 0.1

[0033] Step 2: CA70 aluminum oxide, CA80 aluminum oxide fine powder, silicon powder, α-alumina, light mullite, 85% phosphoric acid, and polyethylene explosion-proof fiber are stirred and mixed in an HNX-500 planetary mixer for 8 minutes to mix the blank.

[0034] Step three: keep the above-mentioned pre-mixed blanks at a temperature of 25° C. for 36 hours.

[0035] Step 4: Place the trapped blank material into a mold to complete the vibration molding of the blank, and dry it under natural conditions for 24 hours to obtain a primary dried blank; place the primary dried blank in a tunnel dryer to dry, and obtain a brick blank.

[0036] Step 5: Place the above-mentioned brick embryos into a tunnel kiln and fire them at 1250° C. to obtain standardized modules. The modules are tested after leaving the kiln, and the finished products are marked and stored.

[0037] Example 2

[0038] The refractory material is prepared according to the method in Implementation 1. The difference from the method in Example 1 is that the materials used and the material ratios are selected as (mass percentages), as shown in Table 2.

[0039] Table 2

[0040] Material Ratio CA70 50 CA80 13 Silica powder 0 α-Alumina 0 Lightweight mullite (recycled) 17 80% Phosphoric acid 19.9 Polyethylene explosion-proof fiber 0.1

[0041] The refractory materials prepared in Example 1 and Example 2 can withstand a working temperature of 1500°C without cracking or melting; the density of the refractory materials is less than 1900Kg / m 3, which is only about 60% of the density of current conventional heavy refractory materials; the strength of refractory materials meets the relevant indicators of M7.5 cement mortar masonry MU15 bricks in the national standard "Code for Design of Masonry Structures".

[0042] The above are merely embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention are included in the scope of the claims of the present invention to be approved.

Claims

1. A low-density, high-temperature resistant refractory material. Features: By mass, it comprises 40% to 50% of CA70 cement, 10% to 18% of CA80 cement, 15% to 20% of lightweight mullite and 14% to 35% of a binder.

2. The refractory material according to claim 1, Features: The binder is at a concentration 80%~85% phosphoric acid.

3. The refractory material according to claim 1, Features: It also includes 0-3% silicon powder, 0-3% alpha-alumina and 0.06%-0.1% explosion-proof fiber.

4. The refractory material according to claim 3, Features: The explosion-proof fiber is polyethylene fiber.

5. The refractory material according to claim 4, Features: By mass ratio, including 41% CA70 cement, 18% CA80 cement, 3% silica powder, 3% α-alumina, 20% light mullite, 14.9% phosphoric acid and 0.1% polyethylene fiber.

6. The refractory material according to claim 4, Features: By mass, including 50% CA70 cement, 13% CA80 cement, 17% lightweight mullite, 19.9% ​​phosphoric acid and 0.1% polyethylene fiber.

7. Use of the refractory material according to any one of claims 1 to 6 in high temperature industries.

8. A method for preparing refractory bricks, It is characterized in that The following steps are involved: According to any one of the mass ratios of claims 1 to 6, the raw materials are mixed into a blank; After mixing, the green mold is formed according to the standardized template and dried in a natural state; The dried green embryo is fired in a rotary kiln at 1250°C.

9. A burning pool, It is characterized in that Obtained by stacking the refractory bricks described in claim 8.