Coal gas wet oxidation desulfurization device

Abstract

The utility model discloses a coal gas wet type oxidation method desulfurization device belongs to coal gas purification technical field. Aiming at traditional device gas liquid contact efficiency low, the poor regeneration effect, sulfur recovery is easy to block etc. problem, provided the device containing regenerator, desulfurizing tower, rich liquid tank and sulfur recovery system. Wherein, the regenerator top is equipped with the injector and realizes self -priming air, and the desulfurizing tower divides the pre -desulfurization section and main desulfurization section, and mass transfer is strengthened through the filler layer, and the height difference of regenerator and desulfurizing tower is used to realize the poor liquid self -flow, and the annular structure of foam tank prevents the block, and the sulfur still steam jacket promotes heating efficiency. Process method includes coal gas and poor liquid reverse contact desulfurization, rich liquid is oxidized and regenerated through the injector self -priming air, and sulfur foam filter press smelting recovery sulfur. The innovation lies in the injector self -priming structure energy -conserving, subsection desulfurization process improves the efficiency, and sulfur recovery system optimization. The scheme low energy consumption, regeneration is full, and sulfur recovery rate is greater than or equal to 95%, realizes sulfur resource high -efficient closed -loop utilization, is applicable to industrialized coal gas desulfurization.

Description

Technical Field

[0001] This utility model belongs to the field of coal gas purification technology, specifically relating to a wet oxidation desulfurization device for coal gas, including the structural design of core devices such as a desulfurization tower and a regeneration tower, as well as the supporting desulfurization process. This solution achieves efficient removal of sulfides such as hydrogen sulfide from coal gas and sulfur resource recovery through the synergistic effect of device structural optimization and process innovation. It is applicable to coal gas desulfurization systems in industries such as chemical production and energy supply. Background Technology

[0002] Traditional wet oxidation desulfurization processes for coal gas have several shortcomings. For example, the internal structure of the desulfurization tower is not optimized, resulting in low gas-liquid contact efficiency; the air intake and liquid mixing in the regeneration tower are ineffective, affecting regeneration efficiency; and sulfur recovery-related structures are prone to clogging and have low processing efficiency.

[0003] Based on this, the present invention solves the above problems through a series of structural innovations, thereby improving the system's efficiency, stability, and resource utilization. Utility Model Content

[0004] I. Device Composition

[0005] like Figure 1 As shown, this device includes a regeneration tower (1), a desulfurization tower (2), a rich liquor tank (3), a foam tank (5), a plate and frame filter press (6), a sulfur melting kettle (8), and supporting pipeline pump sets. Each part works in coordination with a specific structural relationship:

[0006] 1. Core Tower Structure:

[0007] Regeneration tower (1): The top is equipped with an ejector (19), whose structure includes a contraction section, a throat section and a diffusion section. The inlet is connected to the rich liquid pipeline. The ejector specification is DN100, the liquid-to-gas ratio is 1:4, the liquid flow rate is 40m³ / h, the gas flow rate is 150m³ / h, and the air intake (16) is connected to the outside air, which can achieve efficient self-absorption of air. The regeneration tower is equipped with a regeneration section (Φ6m×8m) and a regeneration expansion section (Φ9m×6m). The bottom plate of the expansion section is inclined at 4°, the top is open, and the rest is closed.

[0008] Desulfurization tower (2): Internally equipped with multiple adjustable-angle spray layers, each layer featuring 13 atomizing nozzles (nozzle flow rate of 8t / h). The top spray pipe evenly distributes lean liquid, contacting the incoming coal gas in a counter-current manner. The main body of the desulfurization tower has a diameter of Φ9000mm and a wall thickness of 20mm, reinforced with annular channel steel (spacing approximately 3m). It is divided into a pre-desulfurization section and a main desulfurization section.

[0009] Pre-desulfurization section: Three-layer packing with light ceramic plum blossom rings is used, with a specific surface area of ​​124 m² / m³. The rich liquid and coal gas are in co-current contact, accounting for 22% of the treatment capacity.

[0010] Main desulfurization section: Four-layer lightweight ceramic plum blossom ring packing is used, with a specific surface area of ​​124 m² / m³. The lean liquid and coal gas are in countercurrent contact, accounting for 78% of the treatment capacity. The tower is equipped with a liquid distributor assembly (including screen plate, gas riser pipe and supporting H-beam), packing support assembly (steel grating / supporting H-beam) and liquid baffle plate.

[0011] 2. Sulfur recovery system:

[0012] The sulfur foam outlet of the regeneration tower (1) is connected to the foam tank (5). The bottom of the foam tank is equipped with an annular aggregation structure, which is transported to the plate and frame filter press (6) by the sulfur foam pump (12).

[0013] The filtrate separated by the plate and frame filter press (6) enters the filtrate tank and is returned to the system by the filtrate pump (11); the sulfur paste (21) is sent to the sulfur melting kettle (8). The sulfur melting kettle is equipped with a steam jacket and a temperature control device. The steam pressure is 1.0 MPa, the heating area is about 20 m², and the sulfur recovery rate is ≥95%.

[0014] II. Process Method

[0015] 1. Desulfurization stage

[0016] Coal gas enters from the bottom inlet of the desulfurization tower, and the top spray pipe sprays lean liquid through 13 atomizing nozzles (flow rate 8 m³ / h). The lean liquid and coal gas are in counter-current contact in the spray layer. The packing layer of the pre-desulfurization section and the main desulfurization section enhances mass transfer, and hydrogen sulfide is absorbed by the lean liquid. After desulfurization, the coal gas is transported to the boiler from the outlet.

[0017] 2. Rich-liquid regeneration stage

[0018] The rich solution that absorbs hydrogen sulfide flows into the rich solution tank and is then pumped to the ejector of the regeneration tower. After the rich solution is premixed in the pipeline mixing element, it forms a negative pressure to self-absorb air through the throat section of the ejector. The gas-liquid mixture is oxidized and regenerated in the packing layer of the regeneration tower. Due to the height difference between the regeneration tower (13m) and the desulfurization tower (11m), the regenerated lean solution flows by gravity to the top of the desulfurization tower for recycling.

[0019] 3. Sulfur Recovery Method and Process

[0020] The sulfur foam from the regeneration tower flows into the foam tank and accumulates. It is then pumped to the plate and frame filter press by the sulfur foam pump. The filtrate is circulated, and the sulfur paste is melted in the sulfur melting kettle to recover sulfur.

[0021] III. Key Innovation Structure

[0022] 1. Device Innovation

[0023] Ejector self-priming structure: It uses the kinetic energy of the rich liquid to form negative pressure for air intake, eliminating the need for a compressor, saving energy and ensuring a stable intake volume.

[0024] Tower height difference design: The height difference between the regeneration tower and the desulfurization tower enables lean liquor to flow by gravity, eliminating the need for a lean liquor pump and reducing energy consumption and maintenance costs.

[0025] Optimization of sulfur recovery unit: The annular aggregation structure of the foam tank prevents pipe blockage, and the steam jacket and temperature control device of the sulfur melting kettle improve heating efficiency by 40%.

[0026] 2. Methodological Innovation

[0027] Segmented desulfurization process: The pre-desulfurization section is combined with the main desulfurization section in counter-current flow to improve gas-liquid contact efficiency.

[0028] Self-priming air regeneration method: The ejector and the pipeline premixing element work together to significantly improve the sulfide oxidation rate.

[0029] IV. Beneficial Effects

[0030] 1. Significant energy saving effect: The unique ejector and gravity flow structure design eliminates the need for an air compressor and lean liquid pump, reducing system energy consumption and equipment maintenance costs.

[0031] 2. Sufficient regeneration reaction: The mixing elements and ejector in the pre-reaction zone work together to ensure more sufficient gas-liquid contact, significantly improve the sulfide oxidation rate, ensure the stability of the desulfurization cycle, and extend the service life of the desulfurization liquid.

[0032] 3. High resource utilization rate: The innovative structural design of the sulfur recovery system improves the sulfur recovery rate and the filtrate recycling rate, realizing the efficient closed-loop utilization of sulfur resources and improving economic benefits. Attached Figure Description

[0033] To more clearly illustrate the technical solution of this utility model patent, the following related drawings are provided:

[0034] Figure 1 This is a schematic diagram of the coal gas desulfurization process.

[0035] In the diagram: 1. Regeneration tower; 2. Desulfurization tower; 3. Rich liquor tank; 4. Batching tank; 5. Foam tank; 6. Plate and frame filter press; 7. Filtrate tank; 8. Sulfur melting kettle; 9. Rich liquor pump; 10. Alkali pump; 11. Filtrate pump; 12. Sulfur foam pump; 13. Gas inlet; 14. Gas outlet; 15. Air inlet; 16. Air vent; 17. Steam; 18. Condensate; 19. Ejector; 20. Desulfurization waste liquid; 21. Sulfur paste; 22. Steam; 23. Sulfur; 24. Condensate. Detailed Implementation

[0036] Taking coal gas desulfurization as an example, the operation process is explained in conjunction with the device structure:

[0037] 1. Desulfurization stage: Coal gas enters from the bottom of the desulfurization tower (2), and lean liquid is evenly sprayed through the liquid distribution holes of the spray pipe at the top of the tower. After atomization by the nozzle, it comes into countercurrent contact with the rising coal gas at the spray layer. The pre-desulfurization section (three layers of packing, co-current contact) processes 22% of the coal gas volume, and the main desulfurization section (four layers of packing, countercurrent contact) processes 78% of the coal gas volume. Through the optimized spray layer angle adjustment and atomization structure, the gas-liquid mass transfer efficiency is improved, and hydrogen sulfide in the coal gas is absorbed by the lean liquid. After desulfurization, the coal gas is transported to the boiler from the outlet.

[0038] 2. Rich Solution Regeneration Stage: The rich solution that has absorbed hydrogen sulfide flows into the rich solution tank (3) and is then pumped by the rich solution pump (9) to the ejector (19) at the top of the regeneration tower (1). The rich solution is first premixed by the mixing element in the pipeline, and then accelerated by the converging section of the ejector. A negative pressure is formed in the throat section to draw in outside air. The gas-liquid mixture is depressurized by the diffusion section and then enters the packing layer of the regeneration tower. In the packing layer, the gas-liquid contact time is extended, the sulfides are fully oxidized, and the regenerated lean solution flows by gravity along the inclined pipe to the top of the desulfurization tower for recycling.

[0039] 3. Sulfur Recovery Stage: The sulfur foam generated during the regeneration process flows from the outlet of the regeneration tower into the foam tank (5). After being collected by the bottom aggregation structure, it is transported to the plate and frame filter press (6) by the sulfur foam pump (12). The filter cloth traps the sulfur paste (21), and the filtrate is returned to the rich liquid tank (3) by the filtrate pump (11). The sulfur paste enters the sulfur melting kettle (8), and the steam jacket heats the sulfur paste to melt it. The sulfur is discharged from the outlet, and the condensate is discharged from the top of the jacket, realizing the recovery and utilization of sulfur.

[0040] 4. Reagent replenishment: Sodium carbonate, caustic soda flakes, and catalyst are stored in the mixing tank. The reagents are fully dissolved and mixed evenly by the action of the stirring device and heating steam. The prepared reagent solution is transported to the parts of the system that need to be replenished with reagents by the alkali pump (10) to maintain the stability of the composition of the desulfurization liquid and ensure that the desulfurization reaction is continuous and efficient.

[0041] Through the above steps, this utility model achieves efficient desulfurization of coal gas. At the same time, it reduces energy consumption by using designs such as self-priming air injection and lean liquid self-flowing, and produces sulfur products through a sulfur melting kettle, thereby improving resource utilization. It is suitable for industrial coal gas desulfurization scenarios.

Claims

1. A wet oxidation desulfurization device for coal gas, characterized in that, The system includes a regeneration tower (1), a desulfurization tower (2), a rich liquor tank (3), a foam tank (5), a plate and frame filter press (6), and a sulfur melting kettle (8), all connected by a pipeline pump set. The regeneration tower (1) is equipped with an ejector (19) at the top and has a regeneration section and a regeneration expansion section inside. The inlet of the ejector (19) is connected to the rich liquor pipeline, and the air intake (16) is connected to the outside air. The desulfurization tower (2) has multiple adjustable-angle spray layers inside, each equipped with 13 atomizing sprayers. The tower is divided into a pre-desulfurization section and a main desulfurization section. The pre-desulfurization section uses three layers of light ceramic plum blossom ring packing, and the main desulfurization section uses four layers of light ceramic plum blossom ring packing. The specific surface area of ​​the packing is 124 m² / m³. The rich liquid tank (3) is connected to the ejector (19) of the desulfurization tower (2) and the regeneration tower (1) through a pipeline. The sulfur foam outlet of the regeneration tower (1) is connected to the foam tank (5). The foam tank (5) is connected to the plate and frame filter press (6) through the sulfur foam pump (12). The sulfur paste outlet of the plate and frame filter press (6) is connected to the sulfur melting kettle (8).

2. The apparatus according to claim 1, characterized in that, The ejector (19) includes a constriction section, a throat section and a diffusion section, with a specification of DN100, a liquid-to-gas ratio of 1:4, a liquid flow rate of 40 m³ / h and a gas flow rate of 150 m³ / h.

3. The apparatus according to claim 1, characterized in that, The regeneration tower (1) has a regeneration section with dimensions of Φ6m×8m and a regeneration expansion section with dimensions of Φ9m×6m. The bottom plate of the regeneration expansion section is inclined at 4°, the top is open, and the rest is closed.

4. The apparatus according to claim 1, characterized in that, The desulfurization tower (2) has a main body diameter of Φ9000mm and a wall thickness of 20mm. It is reinforced with annular channel steel on the outside, with a channel steel spacing of about 3m.

5. The apparatus according to claim 1, characterized in that, The flow rate of the atomizing nozzle of the desulfurization tower (2) is 8t / h.

6. The apparatus according to claim 1, characterized in that, The pre-desulfurization section processes 22% of the coal gas volume, using rich liquid in co-current contact with the coal gas; the main desulfurization section processes 78% of the coal gas volume, using lean liquid in counter-current contact with the coal gas.

7. The apparatus according to claim 1, characterized in that, The bottom of the foam tank (5) is provided with an annular aggregation structure.

8. The apparatus according to claim 1, characterized in that, The sulfur melting kettle (8) is equipped with a steam jacket and a temperature control device. The steam pressure is 1.0 MPa and the heating area is about 20 m².

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