A configuration mode of refractory material of a top-spraying coal water slurry gasifier cone bottom

Abstract

The present application belongs to the technical field of refractory material, and mainly relates to a configuration mode of water-coal-slurry gasifier lining refractory material. The conical bottom lining of the water-coal-slurry gasifier is composed of working lining refractory material directly contacted with molten slag and back lining refractory material not directly contacted with molten slag. The working lining refractory material is made of silicon carbide-oxide composite shaped refractory material product without Cr2O3. The back lining refractory material is made of Al2O3-SiC-C composite refractory material without Cr2O3. The hot-state bending strength of the silicon carbide-oxide composite refractory material is 25-50 MPa under 1400 DEG C carbon burying, and the thermal shock resistance of the material is greater than or equal to 20 times under 1100 DEG C-ambient temperature water cooling. The thickness of the working lining refractory material is 30%-50% of the sum of the thicknesses of the working lining refractory material and the back lining refractory material. The present application has the advantages of green environmental protection, long service life, safety and the like, and can realize the greenization, long service life and light weight of the lining.

Description

Technical Field

[0001] This invention belongs to the field of refractory material technology, and mainly relates to a configuration method of refractory material for coal-water slurry gasifier lining. Background Technology

[0002] Coal gasification is a chemical process that uses coal as the main carbon source and reacts with steam at high temperatures to produce syngas feedstock, which is then used in the production of chemical raw materials such as ammonia and methanol. Coal-water slurry gasification is one of the mainstream coal gasification technologies, characterized by stable operation, low investment, and high yield, and has been used in my country for approximately 40 years. One typical type of gasifier is the Texaco coal-water slurry gasifier. This gasifier has a vertical, cylindrical furnace chamber. Coal-water slurry and other feedstocks are injected through top burners, while molten slag and syngas are discharged from a conical outlet at the bottom. The furnace shell is made of high-pressure vessel steel, and the inner lining is composed of refractory materials consisting of fire-facing bricks and insulating bricks. Gasification operation... The high temperature and harsh working environment of the furnace lining refractory materials make the fire-facing bricks highly susceptible to damage from the scouring and erosion of gaseous, liquid, and solid substances under high temperature and high furnace pressure, requiring regular maintenance and replacement. Both domestically and internationally, Cr2O3-Al2O3-ZrO2 (commonly known as high-chromium bricks) with Cr2O3 ≥ 75wt% are commonly used as fire-facing bricks. However, the uneven distribution of the flow and temperature fields within the furnace during gasification leads to uneven damage rates of the high-chromium bricks on the fire-facing surface. The lifespan of the high-chromium bricks at the bottom of the cone is only 3000–4000 hours, far lower than the 8000–16000 hours in the cylinder section. The bottom bricks of the cone have become a bottleneck restricting the long-term safe and efficient operation of coal-water slurry gasifiers.

[0003] The main raw material of high-chromium bricks is Cr2O3, which is insoluble in water and chemically stable. However, it can be converted into soluble Cr under high temperature, alkaline, and strong oxidizing environments. 6+ Hexavalent chromium compounds are listed in the first batch of the list of toxic and hazardous water pollutants. According to the preliminary compilation and reference of the list of carcinogens published by the International Agency for Research on Cancer of the World Health Organization, hexavalent chromium is in the list of Group 1 carcinogens. High-chromium bricks have the potential risk of conversion into hexavalent chromium during production, use and after use, which is a potential hidden danger to the green development of coal gasification technology.

[0004] The internal cavity of a coal-water slurry gasifier typically consists of three parts: a hemispherical dome (arch), a cylindrical body, and a conical base. The refractory materials for these three parts are designed relatively independently, facilitating the removal and replacement of the inner lining. The refractory material at the base of the cone primarily consists of two types: chromium corundum castable and high-chromium bricks. The chromium corundum castable is in direct contact with the steel shell, serving two purposes: firstly, it fills and repairs irregular shapes within the cavity; secondly, it possesses a certain degree of slag resistance, providing short-term protection against safety hazards caused by the failure of the fire-facing bricks. The high-chromium bricks at the base are fire-facing bricks, formed by multiple bricks with a special geometric structure, creating a regularly shaped conical opening for easy slag discharge. During gasifier operation, the high-speed gas flow carrying high-temperature coal slag continuously erodes and washes over the high-chromium bricks at the fire-facing surface of the cone, resulting in severe damage to the bricks. In addition, for top-spray single-nozzle gasifiers, the cone bottom is the part farthest from the burner. Start-up and shutdown, coal slurry flow rate, coal slurry composition fluctuations, coal / oxygen ratio fluctuations, etc. cause large fluctuations in the burner flame length and temperature, resulting in large temperature fluctuations at the cone bottom. The high-chromium bricks at this location are severely damaged by thermal shock. Summary of the Invention

[0005] To address the technical problems of short refractory material lifespan caused by severe erosion of the cone bottom lining of a coal-water gasifier by high-temperature molten slag and thermal shock spalling, and the environmental unfriendliness of existing chromium-containing refractory materials, this invention proposes an environmentally friendly configuration method for the cone bottom refractory material of a coal-water slurry gasifier. This method aims to improve the lifespan of the cone bottom lining, eliminate chromium pollution, and promote the long-term, green operation of the coal-water gasifier.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: A method for configuring refractory materials for the cone bottom of a coal-water slurry gasifier is disclosed. The cone bottom lining of the coal-water slurry gasifier consists of two parts: a working lining refractory material that directly contacts the molten slag and a backing refractory material that does not directly contact the molten slag. The working lining refractory material is a Cr2O3-free silicon carbide-oxide composite refractory material. The backing refractory material is a Cr2O3-free Al2O3-SiC-C composite refractory material. The silicon carbide-oxide composite refractory material is a pre-formed product using a mold. The Al2O3-SiC-C composite refractory material is an amorphous bulk material, which is applied by casting or ramming with a binder. The silicon carbide-oxide composite refractory material has a hot flexural strength of 25-50 MPa under 1400℃ coke burial and withstands ≥20 water-cooled thermal shock cycles from 1100℃ to room temperature. The thickness of the working lining refractory material is 30%-50% of the sum of the thicknesses of the working lining refractory material and the backing refractory material.

[0007] The aforementioned silicon carbide-oxide composite refractory material has a thermal conductivity of 5–20 W / (m·K) at 1000℃. During gasification furnace operation, the high thermal conductivity of the working lining facilitates the formation of a large temperature gradient at the cone bottom, resulting in a high-viscosity slag layer on the surface of the working lining material. This protects the interior of the working lining material from erosion, achieving "slag-resistant slag."

[0008] The silicon carbide-oxide composite refractory material is one or a combination of silicon carbide-corundum composite material, silicon carbide-magnesium aluminum spinel composite material, silicon carbide-calcium hexaaluminate composite material, and silicon carbide-calcium zirconate composite material. This type of composite material can resist the erosion of coal slag at high temperatures and has good slag resistance.

[0009] The silicon carbide-oxide composite refractory material contains 2% to 10% Al, Si, Al-Si metals or alloys. The addition of metals or alloys will generate non-oxide low-dimensional phases inside the material, which can improve the material's fracture toughness, oxidation resistance and slag resistance.

[0010] The silicon carbide-oxide composite refractory material is a product fired at a high temperature of 1200–1700℃, or a product dried at a low temperature of 100–200℃ without firing. High-temperature fired products have the advantages of volume stability and chemical stability during use; unfired products can be fired using furnace temperature during the material's use, making them more environmentally friendly and low-carbon.

[0011] The silicon carbide in the silicon carbide-oxide composite refractory material is granular material prepared by electrofusion method, with a purity w(SiC) ≥ 97% and a particle size range of 0.5 mm-5 mm. Electrofused silicon carbide has large grain development, excellent high-temperature performance, and good resistance to coal slag erosion; the purity requirement is... w The requirement of (SiC)≥97% is because if the purity of silicon carbide is low, it is easy to generate SiO2, Fe2O3, Na2O, K2O and other substances that are easy to form low melting point substances at high temperature, which will reduce the high temperature mechanical properties and slag resistance of refractory materials; silicon carbide is required to be in the form of particles rather than fine powder because silicon carbide with larger particle size has better oxidation resistance.

[0012] The Al2O3-SiC-C composite refractory material contains 50%–60% Al2O3 and 20%–30% SiC by mass. Controlling the proportions of Al2O3 and SiC in the composition helps to adjust the material's slag resistance and thermal conductivity, enabling it to act as a safety barrier and withstand molten slag erosion for a short period when the working lining fails.

[0013] The construction sequence of the refractory material for the cone bottom of the coal-water slurry gasifier is as follows: first, the backing refractory material is poured or tamped into the cone bottom furnace shell to form a relatively regular inner cavity. After the inner lining material has a certain strength, the working lining refractory material is built on top of it using refractory mortar of the same material as the working layer as the joint material, so that the cone bottom cavity of the funnel-shaped brick cavity is formed.

[0014] This invention proposes a refractory material configuration for the cone bottom of a coal-water slurry gasifier. Addressing the prominent problems of existing high-chromium brick working linings, such as severe damage due to thermal shock spalling leading to short working lining life, and the environmentally unfriendly use of chromium-containing refractories, this invention employs a high-temperature resistant, erosion-resistant, thermally shock-resistant, and high-strength silicon carbide-oxide composite material as the working lining. This material can withstand the erosion, scouring, and thermal shock spalling of coal slag, extending the working lining life and reducing the frequency of maintenance and replacement of the cone bottom refractory material. The combination of a silicon carbide-oxide composite refractory working lining and an Al2O3-SiC-C composite refractory backing to form the refractory cone bottom has significant advantages: First, both materials are chromium-free, making them environmentally friendly; second, both are oxide-non-oxide composites, exhibiting good compatibility and strong interfacial bonding; third... Al2O3-SiC-C composite refractories possess a certain degree of resistance to molten slag erosion. When abnormal operation leads to the complete detachment or corrosion of the silicon carbide-oxide composite refractories working lining, they can temporarily resist slag erosion, preventing safety accidents. Fourthly, the combination of amorphous Al2O3-SiC-C composite refractories and fixed-shape silicon carbide-oxide composite refractories allows for efficient adjustment of the geometric dimensions of the construction surface, ensuring construction efficiency and quality. Furthermore, the working lining silicon carbide-oxide composite refractories are required to possess not only high high-temperature flexural strength and thermal shock resistance to resist slag erosion and thermal shock damage, but also a certain thermal conductivity range, which is much higher than that of high-chromium bricks (thermal conductivity of 3~4 W / (m·K) at 1000℃). During gasifier operation, this facilitates the formation of a large temperature gradient at the cone bottom, resulting in a high-viscosity slag layer on the surface of the working lining material, protecting the interior of the working lining material from erosion, achieving "slag-resistant slag" and improving the service life of the working lining.

[0015] This invention proposes a refractory material configuration for the cone bottom of a coal-water slurry gasifier. It combines a shaped silicon carbide-oxide composite material with excellent slag erosion resistance, high strength, and good thermal shock resistance with an unshaped Al2O3-SiC-C composite material with certain slag resistance. The raw materials used are environmentally friendly and do not contain Cr2O3. The furnace lining is erosion-resistant, scour-resistant, and thermal shock-resistant, reducing the damage rate and extending its service life. The combination of the shaped and unshaped materials facilitates construction. The backing uses a slag-resistant material, providing double safety. The bulk density of the two materials is only 2 / 3 of that used in existing technologies, resulting in less weight for the same volume cavity. Compared with existing technologies, this invention has significant advantages such as being environmentally friendly, having a long service life, and being safe. When applied to the cone bottom of a single-nozzle top-spray coal-water slurry gasifier, it can achieve a greener, longer-lasting, and lighter furnace lining. Detailed Implementation

[0016] The invention is illustrated with reference to the given embodiments, but this does not constitute any limitation on the invention. Example 1

[0017] The refractory material configuration for the cone bottom of the coal-water slurry gasifier is as follows: Silicon carbide-corundum composite refractory is used as the working lining refractory material for the cone bottom, and Al2O3-SiC-C composite refractory castable is used as the backing refractory material; the composition of the silicon carbide-corundum composite refractory material is as follows: w (SiC) = 68.3% 、w (Al2O3)=29.6%, w (Cr2O3)=0, bulk density 2.90 g / cm³ 3 The hot flexural strength under 1400℃ carbon embedding is 25MPa, the thermal shock resistance is 20 cycles of water cooling from 1100℃ to room temperature, and the thermal conductivity at 1000℃ is 5.0 W / (m·K). It is a machine-pressed product sintered at 1700℃ in a nitrogen atmosphere for final shaping. The composition of Al2O3-SiC-C composite refractory castable is as follows: w (SiC) = 20.0% 、w (Al2O3)=60.0%, w (Cr2O3)=0, calcium aluminate cement is used as the binder; during construction, a mold is first erected, and the Al2O3-SiC-C composite refractory castable mentioned above is mixed with an appropriate amount of water and poured into the cavity formed by the conical bottom steel shell of the gasifier and the mold. After curing and drying, the mold is removed to form a relatively regular inner cavity; silicon carbide-corundum composite refractory bricks are laid in a ring from bottom to top on the metal brick plate, and the bricks are bonded together with silicon carbide-corundum refractory mortar to form a conical bottom cavity with a flared brick body. The total radial thickness of the silicon carbide-corundum composite refractory bricks is 400mm, and the total radial thickness of the Al2O3-SiC-C composite refractory castable is 600mm. Example 2

[0018] The refractory material configuration for the cone bottom of the coal-water slurry gasifier is as follows: Silicon carbide-magnesium aluminum spinel composite refractory serves as the working lining, and Al2O3-SiC-C composite refractory castable serves as the backing. The silicon carbide-magnesium aluminum spinel composite refractory is mainly composed of fused silicon carbide particles with a purity w(SiC) ≥ 97% and a particle size range of 0.5mm-5mm, and sintered spinel fine powder, with the addition of 6wt% metallic aluminum powder. After being pressed into shape using a clay press, it is fired at 1400℃ in a nitrogen atmosphere. The composition of the silicon carbide-magnesium aluminum spinel composite refractory is as follows: w (SiC) = 62.2% 、w (Al2O3)=29.8%, w (MgO)=6.9%, w (Cr2O3)=0, bulk density 2.80 g / cm³ 3 The hot flexural strength under carbon embedding at 1400℃ is 50MPa; the thermal shock resistance is 35 cycles of water cooling from 1100℃ to room temperature; the thermal conductivity at 1000℃ is 20.0 W / (m·K); the composition of Al2O3-SiC-C composite refractory castable is as follows: w (SiC) = 30.0% 、w (Al2O3)=50.0%, w (Cr2O3)=0, with calcium aluminate cement as the binder. During construction, a mold is first erected. The Al2O3-SiC-C composite refractory castable described above is mixed with an appropriate amount of water and poured into the cavity formed by the gasifier's conical bottom steel shell and the mold. After curing and drying, the mold is removed to create a relatively regular inner cavity. Silicon carbide-magnesium alumina spinel composite refractory bricks are then laid in a ring from bottom to top on a metal brick slab. The bricks are bonded together using silicon carbide-magnesium alumina spinel refractory mortar, forming a conical bottom cavity with a funnel-shaped brick body. The total radial thickness of the silicon carbide-magnesium alumina spinel composite refractory bricks is 300mm, and the total radial thickness of the Al2O3-SiC-C composite refractory castable is 700mm. Example 3

[0019] The refractory material configuration for the cone bottom of the coal-water slurry gasifier is as follows: Silicon carbide-calcium hexaaluminate composite refractory serves as the working lining, and Al2O3-SiC-C composite ramming mix serves as the backing. The silicon carbide-calcium hexaaluminate composite refractory is mainly composed of fused silicon carbide particles with a purity w(SiC) ≥ 98% and a particle size range of 2mm-5mm, and sintered calcium hexaaluminate fine powder, with 10wt% aluminum powder added. After being pressed into shape using a clay press, it is dried at 200℃ without high-temperature firing. The composition of the silicon carbide-calcium hexaaluminate composite refractory is as follows: w (SiC) = 65.2% 、w (Al2O3)=31.3%, w (CaO)=2.9%,w (Cr2O3)=0, bulk density 2.70 g / cm³ 3 The hot flexural strength under carbon embedding at 1400℃ is 35MPa, the thermal shock resistance is 50 cycles of water cooling from 1100℃ to room temperature, and the thermal conductivity at 1000℃ is 16.0 W / (m·K). The composition of Al2O3-SiC-C composite refractory ramming mix is ​​as follows: w (SiC) = 25.0% 、w (Al2O3)=60.0%, w (Cr2O3)=0, with phosphoric acid as the binder. During construction, a mold is first erected. The Al2O3-SiC-C composite refractory ramming mix described above is mixed with an appropriate amount of phosphoric acid solution and then rammed into the cavity formed by the gasifier's conical bottom steel shell and the mold. After curing and drying, the mold is removed to create a relatively regular inner cavity. Silicon carbide-calcium hexaaluminate composite refractory bricks are then laid in a ring from bottom to top on a metal brick support plate. The bricks are bonded together using silicon carbide-calcium hexaaluminate refractory mortar, forming a conical bottom cavity with a funnel-shaped brick body. The total radial thickness of the silicon carbide-calcium hexaaluminate composite refractory bricks is 500mm, and the total radial thickness of the Al2O3-SiC-C composite refractory ramming mix is ​​also 500mm. Example 4

[0020] The refractory material configuration for the cone bottom of the coal-water slurry gasifier is as follows: Silicon carbide-calcium zirconate composite refractory serves as the working lining, and Al2O3-SiC-C composite refractory castable serves as the backing. The silicon carbide-silicon carbide-calcium zirconate composite refractory is mainly composed of fused silicon carbide particles with a purity w(SiC) ≥ 98% and a particle size range of 1mm-5mm, and fused calcium zirconate fine powder, with the addition of 2wt% metallic silicon powder. After being pressed into shape using a clay press, it is fired at 1200℃ in a nitrogen atmosphere. The composition of the silicon carbide-calcium zirconate composite refractory is as follows: w (SiC) = 59.3% 、w (ZrO2)=27.9%, w (CaO)=9.0%, w (Cr2O3)=0, bulk density 3.00 g / cm³ 3 The hot flexural strength under carbon embedding at 1400℃ is 33MPa; the thermal shock resistance is 40 cycles of water cooling from 1100℃ to room temperature; the thermal conductivity at 1000℃ is 16.0 W / (m·K); the composition of Al2O3-SiC-C composite refractory castable is as follows: w (SiC) = 30.0% 、w (Al2O3)=55.0%, w(Cr2O3)=0, with calcium aluminate cement as the binder. During construction, a mold is first erected. The Al2O3-SiC-C composite refractory castable described above is mixed with an appropriate amount of water and poured into the cavity formed by the gasifier's conical bottom steel shell and the mold. After curing and drying, the mold is removed to create a relatively regular inner cavity. Silicon carbide-calcium zirconate composite refractory bricks are then laid in a ring from bottom to top on a metal brick support plate. The bricks are bonded together using silicon carbide-calcium zirconate refractory mortar, forming a conical bottom cavity with a funnel-shaped brick body. The total radial thickness of the silicon carbide-calcium zirconate composite refractory bricks is 500mm, and the total radial thickness of the Al2O3-SiC-C composite refractory castable is 1000mm. Example 5

[0021] The refractory material configuration for the cone bottom of the coal-water slurry gasifier consists of two types of silicon carbide-oxide composite refractory materials: silicon carbide-magnesium aluminum spinel composite and silicon carbide-calcium hexaaluminate composite. The working lining refractory material is made of Al2O3-SiC-C composite refractory castable as the backing refractory material. The silicon carbide-magnesium aluminum spinel composite refractory material is mainly composed of fused silicon carbide particles with a purity w(SiC) ≥ 97% and a particle size range of 0.5mm-5mm, and sintered spinel fine powder, with the addition of 6wt% metallic aluminum powder. After being pressed into shape using a clay press, it is fired at 1400℃ in a nitrogen atmosphere. The composition of the silicon carbide-magnesium aluminum spinel composite refractory material is as follows: w (SiC) = 62.2% 、w (Al2O3)=29.8%, w (MgO)=6.9%, w (Cr2O3)=0, bulk density 2.80 g / cm³ 3 The hot flexural strength under 1400℃ carbon embedding is 50MPa, the thermal shock resistance is 35 cycles of water cooling from 1100℃ to room temperature, and the thermal conductivity at 1000℃ is 20.0 W / (m·K). The silicon carbide-calcium hexaaluminate composite refractory material is mainly composed of fused silicon carbide particles with a purity w(SiC) ≥98% and a particle size range of 2mm-5mm, and sintered calcium hexaaluminate fine powder, with the addition of 10wt% metallic aluminum powder. After being pressed into shape using a clay press, it is dried at 200℃ without high-temperature firing. The composition of the silicon carbide-calcium hexaaluminate composite refractory material is as follows: w (SiC) = 65.2% 、w (Al2O3)=31.3%, w (CaO)=2.9%, w (Cr2O3)=0, bulk density 2.70 g / cm³ 3 The hot flexural strength under carbon embedding at 1400℃ is 35MPa, the thermal shock resistance is 50 cycles of water cooling from 1100℃ to room temperature, and the thermal conductivity at 1000℃ is 16.0 W / (m·K). The composition of Al2O3-SiC-C composite refractory castable is as follows: w(SiC) = 30.0% 、w (Al2O3)=50.0%, w (Cr2O3)=0, with calcium aluminate cement as the binder. During construction, a mold is first erected. The Al2O3-SiC-C composite refractory castable mentioned above is mixed with an appropriate amount of water and then poured into the cavity formed by the gasifier cone bottom steel shell and the mold. After curing and drying, the mold is removed to form a relatively regular inner cavity. On the metal brick plate, silicon carbide-magnesium aluminum spinel composite refractory bricks are laid from bottom to top in the annular slag opening section. The bricks are bonded together with silicon carbide-magnesium aluminum spinel refractory mortar. In the trumpet-mouth section, silicon carbide-calcium hexaaluminate composite refractory bricks are laid, and the bricks are bonded together with silicon carbide-calcium hexaaluminate refractory mortar, forming a cone bottom cavity of the trumpet-mouth brick body. The total radial thickness of silicon carbide-magnesium aluminum spinel composite refractory bricks is 400 mm, the total radial thickness of silicon carbide-calcium hexaaluminate composite refractory bricks is 350 mm, and the total radial thickness of Al2O3-SiC-C composite refractory castable is 650 mm. Example 6

[0022] The refractory material configuration for the cone bottom of the coal-water slurry gasifier is as follows: Silicon carbide-calcium hexaaluminate composite refractory serves as the working lining, and Al2O3-SiC-C composite refractory castable serves as the backing. The silicon carbide-calcium hexaaluminate composite refractory is mainly composed of fused silicon carbide particles with a purity w(SiC) ≥ 97% and a particle size range of 0.5mm-5mm, and sintered calcium hexaaluminate fine powder, with the addition of 5wt% Al-Si alloy powder. After being pressed into shape using a clay press, it is dried at 100℃ without high-temperature firing. The composition of the silicon carbide-calcium hexaaluminate composite refractory is as follows: w (SiC) = 60.7% 、w (Al2O3) = 33.6%, w (CaO)=3.2%, w (Cr2O3)=0, bulk density 2.75 g / cm³ 3 The hot flexural strength under carbon embedding at 1400℃ is 38 MPa; the thermal shock resistance is 50 cycles of water cooling from 1100℃ to room temperature; and the thermal conductivity at 1000℃ is 14.8 W / (m·K). The composition of Al2O3-SiC-C composite refractory castable is as follows: w (SiC) = 25.0% 、w (Al2O3)=60.0%, w(Cr2O3)=0, with calcium aluminate cement as the binder. During construction, a mold is first erected. The Al2O3-SiC-C composite refractory ramming mix described above is mixed with an appropriate amount of water and poured into the cavity formed by the gasifier's conical bottom steel shell and the mold. After curing and drying, the mold is removed to create a relatively regular inner cavity. Silicon carbide-calcium hexaaluminate composite refractory bricks are then laid in a ring from bottom to top on a metal brick slab. The bricks are bonded together using silicon carbide-calcium hexaaluminate refractory mortar, forming a conical bottom cavity with a funnel-shaped brick body. The total radial thickness of the silicon carbide-calcium hexaaluminate composite refractory bricks is 400mm, and the total radial thickness of the Al2O3-SiC-C composite refractory castable is 600mm.

Claims

1. A configuration of refractory material for the cone bottom of a coal-water slurry gasifier, wherein the cone bottom lining of the coal-water slurry gasifier consists of two parts: a working lining refractory material that directly contacts the molten slag and a back lining refractory material that does not directly contact the molten slag, characterized in that: The working lining refractory material is a Cr2O3-free silicon carbide-oxide composite refractory; the backing refractory material is a Cr2O3-free Al2O3-SiC-C composite refractory; the silicon carbide-oxide composite refractory is a pre-formed product using a mold; the Al2O3-SiC-C composite refractory is an unshaped bulk material, which is applied by casting or ramming with a binder; the silicon carbide-oxide composite refractory has a hot flexural strength of 25-50 MPa under 1400℃ carbon embedding and withstands ≥20 water-cooled thermal shock cycles from 1100℃ to room temperature; the thickness of the working lining refractory is 30%-50% of the sum of the working lining and backing refractory thicknesses; the thermal conductivity of the silicon carbide-oxide composite refractory at 1000℃ is 5-20. W / (m·K); the silicon carbide-oxide composite refractory material is one or a combination of silicon carbide-corundum composite material, silicon carbide-magnesium aluminum spinel composite material, silicon carbide-calcium hexaaluminate composite material, and silicon carbide-calcium zirconate composite material; the Al2O3-SiC-C composite refractory material has an Al2O3 mass fraction of 50%~60% and a SiC mass fraction of 20%~30%.

2. The refractory material configuration method for the cone bottom of a coal-water slurry gasifier as described in claim 1, characterized in that: The silicon carbide-oxide composite refractory material contains 2% to 10% Al, Si, or Al-Si alloy.

3. The refractory material configuration method for the cone bottom of a coal-water slurry gasifier as described in claim 1, characterized in that: The silicon carbide-oxide composite refractory material is a product fired at a high temperature of 1200-1700℃, or a non-fired product dried at a low temperature of 100-200℃.

4. The refractory material configuration method for the cone bottom of a coal-water slurry gasifier as described in claim 1, characterized in that: The silicon carbide-oxide composite refractory material is composed of silicon carbide particles prepared by electrofusion method, with a purity w(SiC) ≥ 97% and a particle size range of 0.5 mm to 5 mm.