Integrated process burner in coal water slurry gasification furnace

Abstract

The utility model discloses an integrated process burner in a coal water slurry gasification furnace, which is characterized by comprising a central pipe, a coal slurry pipe and an outer ring pipe from inside to outside, an inner ring gap is formed between the central pipe and the coal slurry pipe, and an outer ring gap is formed between the coal slurry pipe and the outer ring pipe; the pipe wall of the outer ring pipe comprises an annular cavity, a separation ring is arranged in the annular cavity and divides the annular cavity into an inner annular channel and an outer annular channel, and the inner annular channel and the outer annular channel are communicated at the head of the process burner. And the central pipe, the coal slurry pipe and the outer ring pipe are integrally processed and formed by overlapping seamless pipes, and are made of Inconel 600. The gasification furnace process burner adopts an integrated structure of the burner nozzle and the cooling jacket, and has the advantages of large heat exchange area, good cooling effect, reasonable thermal stress distribution and long service life.

Description

Technical Field

[0001] This utility model belongs to the field of coal-water slurry gasification technology, specifically relating to an integrated process burner in a coal gasification device gasifier. Background Technology

[0002] The coal gasification process involves feeding raw coal and limestone into a coal mill via a weighing feeder. After thorough grinding, the materials overflow to the mill outlet and pass through a drum screen, resulting in a coal slurry that flows into a slurry tank. The slurry is then pressurized to 8.3 MPa by a high-pressure pump and sent to the gasifier as feedstock for coal-water slurry gasification. It, along with oxygen from the air separation unit, enters the gasifier burner. At approximately 1400℃ and 6.603 MPa, the coal slurry and oxygen undergo a partial oxidation reaction in the gasifier combustion chamber, producing syngas primarily composed of CO, H2, CO2, and H2O.

[0003] Due to the high-temperature and high-pressure combustion environment of the gasifier, the burner is prone to cracking and other damage, therefore, it needs to be cooled. There are two traditional water cooling methods: one is a coil-type structure, and the other is a sleeve-type structure.

[0004] One cooling method for burners in coal gasification processes involves adding a water-cooled jacket to their outer side. This jacket typically includes a sleeve and an end cap. The end cap, located at one end of the sleeve, includes an inner wall, an outer wall, and an end plate. The inner and outer walls have sidewall heat exchange structures, and the end plate has multiple raised end-face heat exchange structures distributed on its inner side. This water-cooled jacket primarily utilizes the heat exchange structures on the inner side of the end cap to achieve a large heat exchange area and good cooling effect. However, this structure is complex, with numerous and relatively horizontally distributed spirals. The biggest problem is that the burner head deforms when heated, causing the cooling water to deviate from its flow path. Encountering the protrusions creates turbulence and voids, resulting in poor heat exchange and potential damage to the burner head.

[0005] The process burner tip typically uses a water-cooled jacket, with the cooling water inlet directly reaching the jacket and then being led out through a coil wound around the burner head. Problems encountered in actual operation include:

[0006] 1. Improper temperature control of the cooling water in the cooling water coil causes low-temperature corrosion on the surface of the coil.

[0007] 2. The high-temperature performance of the coil material is unstable, causing coil cracks and backflow of process gas.

[0008] 3. During the bending process of the cooling water coil, the heating temperature and bending speed were not properly controlled, resulting in a larger amount of deformation and thinning of the control tube, causing the overall strength and stiffness of the coil after forming to fail to meet the design values.

[0009] 4. During normal operation, due to the strong gas backflow at the end face of the process burner, slag often accumulates in the gap between the process burner and the inner wall of the gasifier. The coil may also be damaged during the burner removal process.

[0010] Due to the use of the burners, a shutdown and burner replacement operation is required every 30 days, which seriously affects the effective gas output and production cost of the entire unit. Summary of the Invention

[0011] This invention addresses the problems of process burners being prone to cracking due to high temperature and pressure, wear, and short service life. The purpose is to provide an integrated process burner for water-coal slurry gasification furnaces to improve its service life, ensure good cooling effect, and at the same time, have a simple structure, high stability, and are suitable for long-term operation.

[0012] To achieve the above-mentioned objectives, the present invention adopts the following technical solution:

[0013] An integrated process burner for a coal-water slurry gasifier is characterized in that it comprises, from the inside out, a central tube, a coal slurry tube, and an outer ring tube; an inner annular gap is formed between the central tube and the coal slurry tube, and an outer annular gap is formed between the coal slurry tube and the outer ring tube; the wall of the outer ring tube contains an annular cavity, and a partition ring is provided in the annular cavity to divide the annular cavity into inner and outer annular channels, and the inner and outer annular channels are connected at the head of the process burner.

[0014] Furthermore, in the process burner, the central tube, slurry tube, and outer ring tube are integrally formed by seamless tube stacking.

[0015] Furthermore, in the process burner, the separating ring is provided with separating ring fins; preferably, separating ring fins are provided on both sides of the separating ring.

[0016] Furthermore, in the process burner, oxygen enters the gasifier through the central tube and the outer annular gap, while coal slurry enters the gasifier through the inner annular gap.

[0017] Furthermore, in the process burner, cooling water enters from the outer annular channel and flows out from the inner annular channel.

[0018] Furthermore, in the process burner, the central tube, the slurry tube, and the outer ring tube are concentric circles in radial cross-section.

[0019] Furthermore, in the process burner, the central tube, slurry tube, and outer ring tube are made of Inconel 600.

[0020] Furthermore, in the process burner, the outer ring tube and the separator ring are respectively folded inward at a 45° angle along the axial direction at the top of the process burner.

[0021] Beneficial Effects: The gasifier process burner of this utility model adopts an integrated structure of burner nozzle and cooling jacket, which has the advantages of large heat exchange area, good cooling effect, reasonable thermal stress distribution, and long service life. The process burner has a simple structure, high stability, and guaranteed heat exchange effect. The external mixing structure reduces the probability of internal scaling and is suitable for high ash melting point coals and complex working conditions. With the combination of high-temperature alloy and cooling system, the process burner can support continuous and efficient operation for 45 days, reducing the frequency of shutdown maintenance and making it suitable for long-term operation. Attached Figure Description

[0022] Figure 1 A schematic diagram of the Texaco process burner;

[0023] Among them, 1. central pipe, 2. coal slurry pipe, 3. outer ring pipe, 4. central channel, 5. inner ring gap, 6. outer ring gap, 12. cooling water coil, 13. cooling water jacket;

[0024] Figure 2 This is a schematic diagram of the integrated process burner in the coal-water slurry gasifier of this utility model.

[0025] Among them, 1. central pipe, 2. coal slurry pipe, 3. outer ring pipe, 4. central channel, 5. inner annular gap, 6. outer annular gap, 7. inner annular channel, 8. outer annular channel, 9. partition ring, 10. annular cavity, 11. partition ring fins. Detailed Implementation

[0026] The technical solution of this utility model will be further described in detail below through specific embodiments. However, it should be noted that the following embodiments are only used to describe the content of the invention and do not constitute a limitation on the protection scope of this utility model.

[0027] The burner in a gasifier is just as important as the gasifier itself. The operating status of a gasifier depends on the burner, and it is expensive.

[0028] like Figure 1This is a schematic diagram of a common Texaco process burner, a key piece of equipment in the gasification unit. It has a simple structure, generally a three-channel external mixing design, consisting of a central pipe 1, a coal slurry pipe 2, and an outer ring pipe 3 from the inside out. Oxygen flows through the central channel 4 and the outer ring gap 6, while the coal slurry flows through the inner ring gap 5. Because the Texaco burner is inserted into the gasifier combustion chamber and withstands temperatures of approximately 1400℃, a cooling water coil 12 and a cooling water jacket 13 are installed to prevent burner damage. The cooling water jacket 13 is located at the top of the process burner, with the cooling water inlet directly reaching the jacket, and then extending out through several coils of cooling water coil 12 wrapped around the outside of the burner. In actual operation, low-temperature corrosion on the surface of the cooling water coil 12, cracks in the cooling water coil 12 caused by raw material issues leading to backflow of process gas, increased deformation and thinning of the cooling water coil 12 during bending, and potential damage to the cooling water coil 12 during burner removal all affect the long-term, full-capacity, and optimal operation of the unit.

[0029] This utility model relates to a long-cycle process burner, which adopts an integrated structure of burner nozzle and cooling water jacket and uses high-performance Inconel 600 material. Figure 2 An integrated process burner in a coal-water slurry gasifier includes, from the inside out, a central tube 1, a coal slurry tube 2, and an outer ring tube 3 containing an annular cavity 10. An inner annular gap 5 is formed between the central tube 1 and the coal slurry tube 2, and an outer annular gap 6 is formed between the coal slurry tube 2 and the outer ring tube 3. The central tube 1 contains a central channel 4 through which central oxygen enters the gasifier. The coal slurry flows through the inner annular gap 5, and the outer annular oxygen flows through the outer annular gap 6. In the burner, the coal slurry is fully atomized by the high-speed oxygen flow to facilitate the gasification reaction.

[0030] The integrated process burner still adopts a three-channel external mixing structure. Based on the integrated structure, the central oxygen flow and the outer ring oxygen act together on the coal slurry, breaking the coal slurry into micron-sized droplets through high-speed shear force, significantly increasing the reaction surface area and shortening the gasification reaction time. Oxygen and coal slurry mix at the burner outlet (external mixing design), reducing the risk of internal coking and improving operational stability. The atomized coal slurry undergoes partial oxidation with oxygen in the gasifier combustion chamber (1200–1400℃), mainly generating syngas (comprising CO and H2, accounting for over 80%) and liquid slag. The impact of the central oxygen optimizes the flame morphology and prevents localized high temperatures from damaging the refractory material. The synergistic design of the three channels achieves a carbon conversion rate of over 98%, significantly increasing the concentration of effective components (CO+H2) in the syngas.

[0031] According to the process burner of this utility model, the outer ring tube 3 includes an annular cavity 10, and a partition ring 9 is provided inside the annular cavity 10, dividing the annular cavity 10 into inner and outer annular channels 7 and 8. The inner and outer annular channels 7 and 8 are connected at the head of the process burner, and cooling water enters from the outer annular channel 8 and flows out from the inner annular channel 7. Partition ring fins 11 are provided on both sides of the partition ring 9. The partition ring fins 11 have the functions of guiding flow, increasing heat exchange area, and strengthening the partition ring 9.

[0032] In the process burner, the central tube 1, the coal slurry tube 2, and the outer ring tube 3 are seamlessly stacked and integrally formed into a single structure. Furthermore, the central tube 1, the coal slurry tube 2, and the outer ring tube 3 (including the separating ring 9) are concentric circles in radial cross-section.

[0033] In the process burner, the central tube 1, the slurry tube 2, and the outer ring tube 3 are made of Inconel 600.

[0034] The main chemical composition of Inconel 600 includes nickel (Ni), which, as the main component of the alloy, provides excellent corrosion resistance and high-temperature strength. In addition, the alloy contains 14-17% chromium (Cr), improving oxidation resistance; and 8-12% iron (Fe), which helps to enhance strength and toughness. The alloy also boasts excellent physical properties, with a melting point range of 1370-1425℃. The use of Inconel 600 alloy in this invention brings the following advantages: 1. Excellent resistance to corrosion from reducing, oxidizing, and nitriding media; 2. Excellent resistance to stress corrosion cracking at both room temperature and high temperatures; 3. Excellent resistance to corrosion from dry chlorine and hydrogen chloride gases; 4. Excellent mechanical properties at sub-zero temperatures, room temperature, and high temperatures; 5. Excellent resistance to creep rupture.

[0035] The outer ring pipe 3 and the partition ring 9 are respectively bent inward at a 45° angle along the axial direction at the top of the process burner. At the top of the process burner, the cooling water enters the outer ring pipe 3 along the partition ring 9 at a 135° angle and exits at a 45° angle with the inner and outer annular channels 7 and 8.

[0036] This utility model's process burner is manufactured by integrating the burner nozzle and cooling water jacket into a single unit. The integrated process burner has a simple structure and ensures efficient heat exchange. The external mixing structure reduces the probability of internal scaling, making it suitable for high-ash-melting-point coals and complex operating conditions. Combined with a high-temperature resistant alloy and cooling system, the burner can operate continuously and efficiently for 45 days, reducing the frequency of shutdowns and maintenance.

[0037] After adopting the long-cycle burner of this invention, the replacement cycle has been reduced from 30 days to 45 days. This translates to cost savings of approximately 400,000 yuan. If multiple furnaces are operating, the cost reduction and efficiency improvement results will be even more significant.

Claims

1. An integrated process burner for a coal-water slurry gasifier, characterized in that, From the inside out, it includes a central pipe, a coal slurry pipe, and an outer ring pipe. An inner annular gap is formed between the central pipe and the coal slurry pipe, and an outer annular gap is formed between the coal slurry pipe and the outer ring pipe. The wall of the outer ring pipe contains an annular cavity, and a partition ring is provided in the annular cavity to divide the annular cavity into inner and outer annular channels. The inner and outer annular channels are connected at the head of the process burner.

2. The integrated process burner in the coal-water slurry gasifier according to claim 1, characterized in that, The central pipe, slurry pipe, and outer ring pipe are integrally formed by seamless pipe stacking.

3. The integrated process burner in the coal-water slurry gasifier according to claim 1, characterized in that, The separator ring is provided with separator ring fins.

4. The integrated process burner in the coal-water slurry gasifier according to claim 3, characterized in that, The separator ring has separator ring fins on both sides.

5. The integrated process burner in the coal-water slurry gasifier according to claim 1, characterized in that, In the process burner, oxygen enters the gasifier through the central tube and the outer annular gap, while coal slurry enters the gasifier through the inner annular gap.

6. The integrated process burner in the coal-water slurry gasifier according to claim 1, characterized in that, In the process burner, cooling water enters from the outer annular channel and flows out from the inner annular channel.

7. The integrated process burner in the coal-water slurry gasifier according to claim 1, characterized in that, In the process burner, the central tube, slurry tube, and outer ring tube are made of Inconel 600.

8. The integrated process burner in the coal-water slurry gasifier according to claim 1, characterized in that, In the process burner, the central tube, the slurry tube, and the outer ring tube are concentric circles in radial cross-section.

9. The integrated process burner in the coal-water slurry gasifier according to claim 1, characterized in that, The outer ring tube and the separator ring are respectively folded inward at a 45° angle along the axial direction at the top of the process burner.

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