Combustion acid liquid collecting device for preventing corrosion of bottom of yellow phosphorus tail gas boiler

Abstract

This utility model discloses a combustion acid collection device for preventing corrosion at the bottom of a yellow phosphorus tail gas boiler. It includes a base, a steam boiler, and a tail-end sump. The base includes a seepage-proof plate and a support column. The tail-end sump is located at the tail end of the steam boiler and consists of a box body and a collection section. This utility model combines the base and tail-end sump at the bottom and tail end of the steam boiler. The base is slightly inclined towards the collection section of the tail-end sump, actively collecting and discharging corrosive acid, preventing it from accumulating on the metal surface at the bottom of the boiler. This eliminates the conditions for low-temperature corrosion at the source, greatly extending the boiler's lifespan. Most of the acid in the flue gas reaches its acid dew point in the tail-end sump, condenses on the pipe wall, and then slides into the collection section for centralized collection and discharge for subsequent processing. Furthermore, the overall inner lining design of the box body completely isolates the sump body from the corrosive acid, significantly extending its service life.

Description

Technical Field

[0001] This utility model relates to the field of yellow phosphorus tail gas treatment technology, specifically to a combustion acid collection device for preventing corrosion at the bottom of a yellow phosphorus tail gas boiler. Background Technology

[0002] With the continuous expansion of yellow phosphorus production scale and the increasing concentration of production sites, my country emits over 2.5 billion cubic meters of yellow phosphorus tail gas annually, leading to increasingly serious pollution. Utilizing this yellow phosphorus tail gas as an energy source could save approximately 9.82 million tons of standard coal annually, while simultaneously reducing pollution emissions, resulting in significant economic and social benefits. Currently, the government mandates the comprehensive utilization of these combustible gases. The simplest and most direct method is combustion in a closed environment, with the high-temperature flue gas generated introduced into a boiler to produce steam, which can then be used in production processes. This effectively recycles the yellow phosphorus tail gas, addressing both energy conservation and environmental protection issues while simultaneously meeting the steam requirements of production processes.

[0003] Yellow phosphorus tail gas can be used as fuel for steam boilers. However, the flue gas from its combustion contains a large amount of acidic substances, which can pollute the environment if directly emitted. Furthermore, at the tail end of the boiler flue, when the temperature drops below 230°C, acidic gases such as SO3 and P2O5 in the flue gas condense to form acidic liquid, which accumulates along with impurities in the flue gas. Because these acidic substances are extremely strong, they can easily cause severe corrosion to equipment, seriously affecting the service life of equipment and pipelines, leading to premature equipment failure. Summary of the Invention

[0004] To address the aforementioned problems, this utility model provides a combustion acid collection device that can promptly collect and remove the acid accumulated in the yellow phosphorus tail gas boiler production line, reduce environmental impact, and prevent corrosion of the bottom of the yellow phosphorus tail gas boiler.

[0005] To achieve the above effects, the present invention adopts the following technical solution: a combustion acid collection device for preventing corrosion at the bottom of a yellow phosphorus tail gas boiler, comprising a base, a steam boiler and a tail liquid collection tank.

[0006] The base includes a seepage-proof plate and support columns. The size of the seepage-proof plate is adapted to the size of the bottom of the boiler, and its surface is provided with an anti-corrosion coating. There are multiple support columns, and mounting plates are installed on the top surface of the support columns. They are installed in pairs in the seepage-proof plate and are arranged at equal intervals along the length of the seepage-proof plate. The height of each group of support columns gradually decreases from left to right. The mounting plates of each support column form an inclined mounting surface. The steam boiler is installed on the mounting surface, and the tail of the steam boiler is located on the lower side of the mounting surface, so that the boiler body is slightly inclined towards the flue gas outlet side.

[0007] The tail liquid collection tank is located at the tail of the steam boiler. The tail liquid collection tank consists of a tank body and a collection part. The tank body is a rectangular structure, with one end face connected to the tail heating surface of the steam boiler. The lower part of this end face has an opening that connects to the flue gas outlet of the steam boiler. A flue gas discharge pipe is installed on the top of the tank body, and the bottom is an open structure. The collection part is an inverted truncated pyramid hopper structure, with its top sealed to the bottom of the tank body. A main drain pipe with a valve is installed at the midpoint of the bottom surface of the collection part, and an inclined side drain pipe with a valve is also installed at the connection between the bottom and side of the collection part on one side of the main drain pipe.

[0008] As an optimization solution for this case, in order to eliminate dead zones in the flow, prevent the accumulation of dirt and viscous acid, and facilitate cleaning and maintenance, the inner corners of the inner wall of the tail liquid collection tank are all designed with rounded arcs, so that the inner corners are rounded.

[0009] As an optimization solution for this case, in order to resist strong acid corrosion and extend service life, the inner wall surfaces of the box and the collection part are covered with an acid-resistant and corrosion-resistant lining.

[0010] As an optimization solution for this case, in order to improve the acid collection effect and minimize the wear on the furnace bottom, a liquid collection tank is provided on the bottom of the furnace of the steam boiler.

[0011] Furthermore, the liquid collection tank has an inverted "U" shaped structure with a large opening at the top and a narrow bottom. Its inner wall surface is covered with an acid-resistant and corrosion-resistant lining, and its bottom surface is fixed to the bottom of the furnace. Its top edge is provided with an integral annular mounting flange, which is connected to the side plate of the furnace and is sealed with ceramic fiber packing.

[0012] As an optimization of this case, in order to improve the acid collection effect, a collection plate that is inclined downwards and faces the collection part is installed above the junction of the tail liquid collection tank and the furnace body of the steam boiler.

[0013] Beneficial effects: ①. This utility model combines a base and a tail liquid collection tank at the bottom and tail of the steam boiler. The base is slightly inclined from the bottom of the steam boiler towards the collection part of the tail liquid collection tank, actively collecting and discharging corrosive acid, preventing it from accumulating on the metal surface at the bottom of the boiler. This eliminates the conditions for low-temperature corrosion at the source, greatly extending the boiler's lifespan. Most of the acid in the flue gas reaches its acid dew point in the tail liquid collection tank, condenses on the pipe wall, and then slides into the collection part for centralized collection and discharge for subsequent processing. Furthermore, the overall inner lining design of the tank completely isolates the liquid collection tank body from the corrosive acid, greatly extending its service life.

[0014] ②. In this utility model, after the flue gas condenses into acid in the tail liquid collection tank, it enters the flue gas discharge pipe, which reduces the acid content in the flue gas, reduces damage to the flue gas discharge pipe, and extends its service life.

[0015] ③. This utility model, by setting a liquid collection tank inside the bottom of the furnace, has a unique inverted trapezoidal "U" shaped structure that ensures that the acid liquid can quickly flow to the lowest point, with no dead corners for liquid accumulation and thorough drainage. In addition, the overall inner lining design completely isolates the liquid collection tank body from the corrosive acid liquid, greatly extending its service life. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the structure of this utility model.

[0017] Figure 2 This is a schematic diagram of the internal structure of the liquid accumulation tank at the tail end of this utility model.

[0018] Figure 3 This is a top view of the internal structure of the liquid collection tank at the tail end of this utility model.

[0019] In the diagram: 1. Steam boiler; 2. Leak-proof plate; 3. Support column; 4. Box body; 5. Collection section; 6. Flue gas discharge pipe; 7. Main drain pipe; 8. Side drain pipe; 9. Collection tank; 10. Collection plate. Detailed Implementation

[0020] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0021] Identical components are represented by the same reference numerals. It should be noted that the terms "front," "rear," "left," "right," "up," and "down" used in the following description refer to directions in the accompanying drawings, while the terms "inner" and "outer" refer to directions toward or away from the geometric center of a specific component, respectively. Furthermore, the accompanying drawings are all in a very simplified form, using non-precise ratios, and are only used to facilitate and clearly illustrate the purpose of the embodiments of this utility model.

[0022] like Figure 1-3 As shown, this embodiment discloses a combustion acid collection device for preventing corrosion at the bottom of a yellow phosphorus tail gas boiler, including a base, a steam boiler 1, and a tail liquid collection tank.

[0023] from Figure 1 As can be seen, the base includes a seepage-proof plate 2 and support columns 3. The size of the seepage-proof plate 2 is adapted to the size of the bottom of the boiler, and its surface is provided with an anti-corrosion coating. There are multiple support columns 3, and mounting plates are installed on the top surface of the support columns 3. They are installed in groups of two in the seepage-proof plate 2 and are arranged at equal intervals along the length of the seepage-proof plate 2. The height of each group of support columns gradually decreases from left to right. The mounting plates of each support column 3 form an inclined mounting surface. The steam boiler 1 is installed on the mounting surface, and the tail of the steam boiler 1 is located on the lower side of the mounting surface, so that the boiler body is slightly inclined towards the flue gas outlet side.

[0024] See Figure 1 As shown in Figure 2, the tail liquid collection tank is located at the tail end of the steam boiler 1. The tail liquid collection tank consists of a tank body 4 and a collecting part 5 connected together. The tank body 4 has a rectangular structure, with one end face connected to the tail heating surface of the steam boiler 1. The lower part of this end face has an opening that connects to the flue gas outlet of the steam boiler 1. A flue gas discharge pipe 6 is installed on the top of the tank body 4, and the bottom is an open structure. (See Figure 2 for details.) Figure 3 The inner corners of its inner wall are all rounded, creating a rounded corner structure. See Figure 1 and Figure 2 The collecting part 5 is an inverted truncated quadrangular hopper structure, with its top sealed to the bottom of the box body 4. A main drain pipe 7 with a valve is installed at the midpoint of the bottom surface of the collecting part 5, and an inclined side drain pipe 8 with a valve is also installed at the connection between the bottom and side surfaces of the collecting part 5 on one side of the main drain pipe 7.

[0025] The inner wall surfaces of the box 4 and the collection section 5 are covered with acid-resistant and corrosion-resistant linings.

[0026] from Figure 2 It can be seen that a liquid collection tank 9 is provided at the bottom of the furnace of the steam boiler 1.

[0027] The liquid collection tank 9 has an inverted "U" shaped structure with a large opening at the top and a narrow bottom. Its inner wall surface is covered with an acid-resistant and corrosion-resistant lining, and its bottom surface is fixed to the bottom of the furnace. Its top edge is provided with an integral ring-shaped mounting flange, which is connected to the side plate of the furnace and is sealed with ceramic fiber packing.

[0028] See Figure 2 A collection plate 10, which is inclined downwards and faces the collection part 5, is installed above the junction of the tail liquid collection tank and the furnace body of the steam boiler 1.

[0029] During operation, the yellow phosphorus tail gas is burned in the furnace of steam boiler 1 to produce steam. During combustion and heating, the impurities in the yellow phosphorus tail gas are converted into acidic substances. At this time, the acidic substances are dissolved in the flue gas in the boiler in the form of "superheated steam" and will not condense. When the flue gas flows through the low-temperature heating surface at the tail end, the temperature drops below the acid dew point. The sulfuric acid, phosphoric acid, etc. dissolved in the steam will quickly condense on the wall of the heating surface tube to form combustion acid liquid. The formed acid liquid drips into the collection tank 9. Protected by an acid-resistant and corrosion-resistant lining, the acid flows downwards along the slope and enters the collection section 5 for collection. As the flue gas continues to flow forward, some of the acid condenses on the collection plate 10 and then enters the collection section 5. When the flue gas enters the tail liquid collection tank, because the temperature of the tank 4 is much lower than that of the boiler tail, a large amount of acid condenses on the inner side wall of the tank and slides into the collection section 5 for centralized discharge for subsequent processing. Finally, the flue gas containing only trace amounts of acidic substances enters the flue gas discharge pipe 6 for further processing.

[0030] The above embodiments are merely illustrative of the principles and effects of this utility model and are not intended to limit the scope of this utility model. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of this utility model. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in this utility model should still be covered by the claims of this utility model.

Claims

1. A combustion acid collection device for preventing corrosion at the bottom of a yellow phosphorus tail gas boiler, comprising a base, a steam boiler (1), and a tail-end liquid collection tank; characterized in that: The base includes a seepage-proof plate (2) and a support column (3). The size of the seepage-proof plate (2) is adapted to the size of the bottom of the boiler. Its surface is provided with an anti-corrosion coating. There are multiple support columns (3). The top surface of the support columns (3) is equipped with an installation plate. They are installed in groups of two in the seepage-proof plate (2) and are arranged at equal intervals along the length of the seepage-proof plate (2). The height of each group of support columns gradually decreases from left to right. The installation plates of each support column (3) form an inclined installation surface. The steam boiler (1) is installed on the installation surface, and the tail of the steam boiler (1) is located on the lower side of the installation surface, so that the boiler body is slightly inclined toward the flue gas outlet side. The tail liquid collection box is located at the tail of the steam boiler (1). The tail liquid collection box consists of a box body (4) and a collection part (5). The box body (4) is a rectangular structure. One end face of the box body is connected to the tail heating surface of the steam boiler (1). The lower part of this end face has an opening and is connected to the flue gas outlet of the steam boiler (1). A flue gas discharge pipe (6) is installed on the top of the box body (4). The bottom is an open structure. The collection part (5) is an inverted truncated pyramid hopper structure. Its top is sealed to the bottom of the box body (4). A main drain pipe (7) with a valve is installed at the midpoint of the bottom surface of the collection part (5). An inclined side drain pipe (8) with a valve is also installed at the connection between the bottom surface and the side surface of the collection part (5) on one side of the main drain pipe (7).

2. The combustion acid collection device for preventing corrosion at the bottom of a yellow phosphorus tail gas boiler according to claim 1, characterized in that: The inner corners of the inner wall of the tail liquid collection tank (4) are all rounded, so that the inner corners are rounded.

3. A combustion acid collection device for preventing corrosion at the bottom of a yellow phosphorus tail gas boiler according to claim 1 or 2, characterized in that: The inner wall surfaces of the box (4) and the collection part (5) are covered with acid-resistant and corrosion-resistant linings.

4. A combustion acid collection device for preventing corrosion at the bottom of a yellow phosphorus tail gas boiler according to claim 1 or 2, characterized in that: The steam boiler (1) is provided with a liquid collection tank (9) at the bottom of the furnace.

5. A combustion acid collection device for preventing corrosion at the bottom of a yellow phosphorus tail gas boiler according to claim 4, characterized in that: The liquid collection tank (9) has an inverted "U" shaped structure with a large opening at the top and a narrow bottom. Its inner wall surface is covered with an acid-resistant and corrosion-resistant lining. Its bottom surface is fixed to the bottom of the furnace. Its top edge is provided with an integral ring-shaped installation flange, which is connected to the side plate of the furnace and is sealed with ceramic fiber packing.

6. A combustion acid collection device for preventing corrosion at the bottom of a yellow phosphorus tail gas boiler according to claim 1 or 2, characterized in that: A collection plate (10) is installed above the junction of the tail liquid collection tank and the furnace body of the steam boiler (1), which is inclined downward and faces the collection part (5).

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