Yellow phosphorus production deslagging flue gas recovery device

Abstract

The utility model discloses a yellow phosphorus production deslagging flue gas recovery device, which relates to the field of chemical waste removal, and comprises a deslagging mechanism and a slag pool mechanism, the slag pool mechanism comprises a containing body and a cover plate, the containing body is communicated with a smoke suction pipe, the cover plate movably covers the containing body, the containing body and the cover plate form a sealed containing cavity, and the containing cavity is communicated with the smoke suction pipe. The slag pool mechanism is communicated with the slag discharging mechanism; the cover plate is formed by splicing a plurality of grating plates, the middle of each grating plate is separated by a cover steel groove, one end of each grating plate is hinged to the cover steel groove, the other end of each grating plate is in a free state, and when the pressure intensity in the containing cavity is smaller than or equal to the atmospheric pressure, each grating plate and the cover steel groove are sealed and covered. According to the utility model, the cover plate is formed by splicing the plurality of grating plates, and the grating plates are arranged to be movable and are matched with the smoke exhaust pipe, so that the aim of avoiding the risk of hurting operators due to the fact that gas in the slag pool expands at a high speed and bursts through the cover plate due to excessive water vapor is achieved.

Description

Technical Field

[0001] The utility model relates to the field of chemical waste removal, in particular to a yellow phosphorus production slag fume recovery device. Background Art

[0002] The electric furnace method is a common method for producing yellow phosphorus. It mainly extracts yellow phosphorus by smelting phosphate ore. Slag removal is required every 3-4 hours. A large amount of flue gas is generated during the slag removal process. Its main components are harmful gases such as phosphorus, sulfur, and carbon monoxide. If it is allowed to be discharged in an unorganized manner, it will pollute the environment and endanger human health. This method usually involves using an electric furnace to smelt the ore. The specific steps are as follows: Raw material preparation: Phosphate ore is the main raw material for this process and usually contains oxides and impurities. These ores are crushed and finely processed so that they can be placed in an electric furnace for smelting; Electric furnace smelting: Phosphate ore is placed in an electric furnace, where electricity is usually used to generate high temperatures to melt the ore. At high temperatures, the oxides in the ore are reduced to phosphorus; Yellow phosphorus extraction: After smelting, the liquid state of the yellow phosphorus produced is collected. This is to ensure high-purity yellow phosphorus by controlling the temperature and smelting conditions. This will produce flue gas and waste slag, which contain harmful substances such as sulfur and phosphorus, posing potential risks to the environment and human health. Therefore, it is particularly important to pay attention to emission treatment and flue gas purification for this production method.

[0003] At present, most of the yellow phosphorus production slag discharge places are open, and the flue gas in the slag discharge process is not centrally treated. In addition, the slag pool covers are mostly open or integral covers. When the high-temperature molten slag flows into the slag pool, it is quenched into blocks or particles by water. At the same time, the water in the slag pool generates a large amount of water vapor due to the large amount of heat energy entering. Since the water vapor contains phosphoric acid, it is corrosive and will not only corrode the electrical equipment in the plant, causing safety hazards, but also cause harm to the environment and human health. When the slag pool cover is an integral cover, due to excessive water vapor, the gas in the slag pool will expand rapidly, thereby breaking the cover, which may cause harm to the operators. Therefore, it is an objective need to develop a recovery device with a reasonable structure, low flue gas treatment cost, and good flue gas treatment effect.

[0004] In view of this, this application is hereby filed. Utility Model Content

[0005] The utility model aims to provide a yellow phosphorus production slag discharge fume recovery device, which solves the problem in the prior art that when an integral cover plate is set for a slag pool, the gas in the slag pool expands extremely rapidly due to excessive water vapor, breaks open the cover plate, and causes harm to operators by configuring a cover plate to be spliced ​​with a plurality of gratings, and configuring the grating to be movable and cooperate with a smoke extraction pipe.

[0006] The embodiment of the utility model is realized through the following technical scheme: a yellow phosphorus production slag discharge fume recovery device, including a slag discharge mechanism and a slag pool mechanism, the slag pool mechanism includes a containing body and a cover plate, the containing body is connected to a smoke extraction pipe, the cover plate can be movably covered on the containing body, the containing body and the cover plate form a sealed containing chamber, and the slag pool mechanism is connected to the slag discharge mechanism.

[0007] The cover plate is composed of a plurality of grid plates, each of which is separated by a cover steel groove in the middle. One end of each grid plate is hinged to the cover steel groove, and the other end is free. When the pressure in the containment chamber is less than or equal to atmospheric pressure, each grid plate is sealed and covered with the cover steel groove.

[0008] Preferably, when the upward thrust of the smoke in the containing chamber on the cover plate is equal to the sum of the weight of the cover plate and the friction between the cover plate and the containing body, a gap is formed between the grid plate and the cover steel groove.

[0009] Preferably, an exhaust pipe is installed on the slag discharge mechanism.

[0010] Preferably, the exhaust pipe is installed on the top of the slag discharge mechanism.

[0011] Preferably, a plurality of side doors are hinged on the side of the slag discharge mechanism, and when the side doors are closed, the slag discharge mechanism is in a sealed state.

[0012] Preferably, a slag discharge steel trough is provided on the top of the slag discharge mechanism, and the top of the slag discharge mechanism is sealed by a plurality of top doors, which are engaged with the slag discharge steel trough.

[0013] Preferably, the top door is an upwardly arched structure.

[0014] Preferably, there are two or more side doors.

[0015] Preferably, the slag discharge mechanism is connected to the slag pool mechanism through a pipeline mechanism.

[0016] Preferably, a conveying mechanism is arranged in the pipeline mechanism.

[0017] Compared with the prior art, the embodiments of the present invention have the following advantages and beneficial effects:

[0018] The utility model provides a yellow phosphorus production slag removal fume recovery device, in which the cover plate of the slag pool mechanism is arranged into a plurality of gratings, which are hinged to the cover steel trough. When the gas pressure in the container is relatively small, the fume is discharged from the smoke extraction pipe. If the pressure in the container is relatively large and the discharge speed of the smoke extraction pipe is smaller than the new amount of fume in the container, the fume in the container will slowly accumulate and the pressure will gradually increase. For the existing one-piece movable cover plate, the cover plate will be blown open by the smoke, posing a threat to the safety of the operators. With regard to the cover plate structure provided by the utility model, when the pressure in the container is relatively large, the grating plate will be subjected to the pressure and rotate upward. At this time, a gap will be formed between the grating plate and the cover steel trough, releasing part of the smoke to prevent the cover plate from being blown open. When the pressure in the container decreases, the grating plate is rotated back to the sealed position by the action of gravity or elastic force, and the smoke extraction pipe collects the smoke.

[0019] In general, the embodiment of the utility model provides a yellow phosphorus production slag removal fume recovery device which is composed of a cover plate formed by splicing a plurality of gratings, and the gratings are arranged to be movable and cooperate with a smoke extraction pipe to achieve the purpose of preventing the slag pool from expanding rapidly due to excessive water vapor, which may break open the cover plate and cause risk of injury to the operators. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions of the embodiments of the utility model, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the utility model and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying creative work.

[0021] Figure 1 A schematic diagram of the structure of a slag fume recovery device for yellow phosphorus production provided by an embodiment of the utility model;

[0022] Figure 2 A schematic structural diagram of a slag fume recovery device for yellow phosphorus production provided in an embodiment of the utility model.

[0023] Marks and corresponding parts names in the attached drawings:

[0024] 1-containment body, 2-cover plate, 3-smoke extraction pipe, 4-grating, 5-cover steel trough, 6-exhaust pipe, 7-side door, 8-slag discharge steel trough, 9-top door, 10-pipeline mechanism, 100-slag pool mechanism, 200-slag discharge mechanism. DETAILED DESCRIPTION

[0025] In order to make the purpose, technical solution and advantages of the embodiment of the utility model clearer, the technical solution in the embodiment of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiment of the utility model. Obviously, the described embodiment is a part of the embodiment of the utility model, not all of the embodiments. The components of the embodiment of the utility model described and shown in the drawings here can be arranged and designed in various different configurations.

[0026] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the present invention to be protected, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0027] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0028] In the description of the present invention, it should be noted that the terms "first", "second", "third", etc. are only used to distinguish the description and cannot be understood as indicating or implying relative importance.

[0029] Example

[0030] like Figure 1-2 As shown, an embodiment of the utility model provides a yellow phosphorus production slag discharge fume recovery device, comprising a slag discharge mechanism 200 and a slag pool mechanism 100, wherein the slag discharge mechanism 200 is used to discharge the waste slag in the yellow phosphorus production process and transfer it to the slag pool mechanism 100, and the slag pool mechanism 100 is used to store and stack the waste slag transferred by the slag discharge mechanism 200, wherein the slag pool mechanism 100 comprises a container 1 and a cover plate 2, the container 1 is connected to a smoke extraction pipe 3, the cover plate 2 can be movably covered on the container 1, the container 1 and the cover plate 2 form a sealed container chamber, and the slag pool mechanism 100 is connected to the slag discharge mechanism 200.

[0031] Specifically, the container 1 is a structure for containing high-temperature slag, which is usually a large container or tank. The specific shape and size are not limited here and can be designed according to the actual output or demand. The container 1 is connected to the smoke pipe 3 so that the generated smoke can smoothly enter the smoke pipe 3 to prevent the smoke from polluting the environment, causing harm to the human body or wasting resources. The smoke can be recovered and treated before being discharged. Specifically, the existing smoke treatment technology can be used, which will not be elaborated here.

[0032] The cover plate 2 is a structure covering the container 1, which can be movably covered on the container 1. The movability of the cover plate 2 allows it to be opened when needed to facilitate slag discharge operations. At the same time, the container 1 can be sealed during normal operation to prevent the corrosive hot steam generated by the water quenching process from leaking into the environment and a large amount of heat energy is wasted. When the cover plate 2 is covered on the container 1, a sealed containing chamber is formed. This structure prevents the corrosive hot steam generated by the water quenching process from leaking into the environment and a large amount of heat energy is wasted, thereby reducing potential harm to the environment and personnel. The slag pool mechanism 100 is connected to the slag discharge mechanism 200, which can be directly connected or connected through a pipeline or other connection methods. This structure ensures that the slag discharge mechanism 200 can transfer the high-temperature slag to the slag pool mechanism 100 for subsequent processing and discharge.

[0033] The key to the utility model is that the cover plate 2 is composed of a plurality of grid plates 4 spliced ​​together, each grid plate 4 is separated by a cover steel groove 5 in the middle, one end of each grid plate 4 is hinged to the cover steel groove 5, and the other end is in a free state, when the pressure in the accommodating chamber is less than or equal to the atmospheric pressure, each grid plate 4 is sealed and covered with the cover steel groove 5. Specifically, the cover plate 2 is composed of a plurality of gratings 4, which are interconnected to form an integral cover plate 2 structure. One end of each grating 4 is hinged to the cover steel groove 5, which means that the grating 4 can move relative to the cover steel groove 5 through the hinge connection, and the other end of the grating 4 is in a free state, that is, the end is not directly connected to any supporting structure, so that the grating 4 can move relatively freely under certain conditions. In this practical embodiment, the movement of the grating 4 is achieved by rotating around the cover steel groove 5, that is, the cover steel groove 5 is a component connecting the gratings 4, located in the middle of each grating 4, separating adjacent gratings 4, and the cover steel groove 5 allows the grating 4 to be hinged at one end to provide rotational support for the grating 4.

[0034] During operation, when the slag discharge mechanism 200 discharges high-temperature slag into the slag pool mechanism 100, the corrosive flue gas and heat energy of the slag pool mechanism 100 will gradually accumulate due to the water quenching effect. At this time, the flue gas is only discharged from the smoke pipe 3. As the amount of slag discharge in the slag pool mechanism 100 gradually increases, the rate of new flue gas in the slag pool mechanism 100 also gradually increases. Since the exhaust capacity of the smoke pipe 3 is limited, even in the continuous exhaust, the amount of flue gas in the slag pool mechanism 100 will gradually increase, so that the pressure in the slag pool mechanism 100 continues to increase. For the recovery device provided by the embodiment of the utility model, when the pressure in the accommodation chamber is less than or equal to atmospheric pressure, each grid plate 4 is sealed and covered with the cover steel trough 5. This covering state is achieved by the gravity of the grid plate 4. Of course, a spring can be installed in the hinged structure, so that the grid plate 4 and the cover steel trough 5 can also be covered under the action of the elastic force. This structure ensures that under appropriate pressure conditions, the grid plate 4 can form an effective seal with the cover steel trough 5, thereby preventing the leakage of harmful gases and water vapor. When the pressure in the containment chamber continues to increase and increases to a point where the pressure exerted on the cover plate 2 is equal to the weight of the cover plate 2 itself, the cover plate 2 will be at risk of being overturned. However, due to the unique structure of the utility model, the pressure of the smoke in the containment chamber will push the grating 4 to rotate in advance, so that the free end of the grating 4 is separated from the cover steel trough 5, creating a gap, so that the smoke in the slag pool mechanism 100 can be partially discharged from the gap, thereby reducing the pressure in the slag pool mechanism 100 and preventing the cover plate 2 from being overturned.

[0035] It should be noted that the shape of the grating 4 is not limited here and can be specifically designed according to the volume or structure of the actual operation. Similarly, the number of gratings 4 is not limited here. For the sake of easy understanding, in the embodiment of the utility model, the containing body 1 of the slag pool mechanism 100 is set as a rectangular structure, and the cover plate 2 is set as a rectangular structure. The gratings 4 can be arranged in four rows in each row, with a total of eight rows, that is, 32 gratings 4 are arranged. In the actual operation process, the critical pressure for the rotation of each grating 4 can be set to be different. In this way, the number of gratings 4 opened can be limited by the pressure in the containing body 1. Under the condition of ensuring that the cover plate 2 is not overturned, the purpose of minimizing the emission of smoke from the gaps of the gratings 4 is achieved.

[0036] At the same time, in order to reduce the emission of smoke from the gap of the grid plate 4, the embodiment of the utility model also limits the critical point of the upward rotation of the grid plate 4. In the actual operation process, it can be adjusted according to the gravity of the grid plate 4, the resistance of the hinge, the elastic force of the spring, etc. The limitation of the embodiment of the utility model is as follows: when the upward thrust of the smoke in the receiving chamber on the cover plate 2 is equal to the sum of the gravity of the cover plate 2 and the friction between the cover plate 2 and the receiving body 1, a gap is formed between the grid plate 4 and the cover steel groove 5. This structure is designed based on the balance of forces. Specifically, when the smoke in the receiving chamber applies an upward thrust to the cover plate 2, this thrust will try to lift the cover plate 2. The gravity of the cover plate 2 itself is downward, trying to pull the cover plate 2 back to its original position. There is friction on the surface where the cover plate 2 contacts the receiving body 1. The direction of this friction is to hinder the movement of the cover plate 2, which is opposite to the movement direction of the cover plate 2. When the thrust of smoke on the cover plate 2, the gravity of the cover plate 2 and the friction between the cover plate 2 and the container 1 are balanced, a gap is formed between the grid plate 4 and the cover steel groove 5. This structure can prevent the grid plate 4 from being opened prematurely, and can reduce the emission of smoke from the gap of the grid plate 4.

[0037] Furthermore, an exhaust pipe 6 is installed on the slag discharge mechanism 200, the purpose of which is to effectively remove part of the flue gas before the waste slag enters the slag pool mechanism 100, so as to reduce the flue gas burden of the slag pool mechanism 100. Similarly, the exhaust pipe 6 is connected to the subsequent waste gas treatment unit for purification or recovery. The exhaust pipe 6 is usually connected to an exhaust device, such as a fan or an exhaust fan. These devices generate negative pressure, thereby causing the waste gas in the slag discharge mechanism 200 to be sucked into the pipeline system. As a preferred embodiment of the utility model, the exhaust pipe 6 can be installed on the top of the slag discharge mechanism 200. Installing it on the top can utilize the direction of natural airflow, so that the waste gas can enter the exhaust pipe 6 more easily without the need for additional power-assisting equipment. This design also helps to prevent waste gas from being retained in the slag discharge mechanism 200. At the same time, the exhaust pipe 6 is located at the top of the slag discharge mechanism 200, usually away from the working area of ​​the operator, which helps to reduce the operator's direct contact with harmful gases. Installing it at the top can reduce the risk of exhaust gas blocking in the pipe. When the exhaust gas flows upward, there are usually fewer sediments and solid particles, thus reducing the risk of pipe blockage.

[0038] Furthermore, a plurality of side doors 7 are hinged on the side of the slag discharge mechanism 200. When the side door 7 is closed, the slag discharge mechanism 200 is in a sealed state. Specifically, through the design of the side door 7, the operator can easily enter or observe the interior of the slag discharge mechanism 200 to inspect and repair the slag discharge. When the side door 7 is closed, the slag discharge mechanism 200 is in a sealed state, that is, during the slag discharge process, this structure helps to prevent harmful gases, smoke or other waste gases from leaking into the surrounding environment. At this time, the smoke can only enter the slag pool structure through the waste slag or be discharged from the exhaust pipe 6, ensuring the protection of the environment and the operator. When the slag discharge is completed, the interior of the slag discharge mechanism 200 will be cleaned. At this time, the side door 7 can be opened, and the operator enters the interior of the slag discharge mechanism 200 for cleaning or maintenance. This structure ensures that the design of the side door 7 can regularly inspect and maintain the slag discharge mechanism 200 to ensure the normal operation and sealing performance of the side door 7. It helps to ensure the safety and environmental protection of the entire system.

[0039] In the embodiment of the utility model, a slag discharge steel trough 8 is provided at the top of the slag discharge mechanism 200, and the top of the slag discharge mechanism 200 is sealed by a plurality of top doors 9, and the top doors 9 are engaged with the slag discharge steel trough 8. Specifically, the slag discharge steel trough 8 is located at the top of the slag discharge mechanism 200, and is a trough-shaped structure along the length of the slag discharge mechanism 200, which is used to guide the designated area where the top door 9 is engaged. The top door 9 is a door installed at the top of the slag discharge mechanism 200. Through the plurality of top doors 9, the interior of the slag discharge mechanism 200 can be easily observed. This structure enables the top door 9 to be quickly opened for slag discharge inspection and maintenance operations when necessary. Through the engagement of the top door 9 with the slag discharge steel trough 8, the closed state of the slag discharge mechanism 200 is achieved, which helps to prevent harmful gases, smoke or other waste gases from leaking into the surrounding environment, and ensure the safety of the environment and operators. In the slag discharge process, there may be a flow of molten slag at a higher temperature. The closed design of the top door 9 helps to prevent the slag from splashing onto the surrounding environment or equipment. In general, the movable top door 9 makes the slag discharge operation more convenient. Workers can choose to open part or all of the top door 9 without opening the entire top structure. Preferably, the top door 9 can be set to an upward arched structure. When the top door 9 is deformed by heat expansion, the arched structure is easier to restore than the flat structure. The arched structure has a better load-bearing capacity at the top, and this structure can better support the weight above the top door 9, such as equipment or other structures attached to the top door 9. The arched structure helps prevent dust or other particles from accumulating on the top door 9. Due to the geometric shape of the arch, dust tends to slide off more easily, reducing adhesion to the top door 9, while avoiding water accumulation, and can also improve the overall structural stability of the top door 9, especially in the face of external forces or pressure changes, which helps to reduce deformation and ensure airtightness.

[0040] Furthermore, there are more than two side doors 7. By providing more than two side doors 7, the operator can choose to open some or all of the side doors 7 to adapt to different operating requirements, providing more flexible slag discharge options; importantly, multiple side doors 7 can improve the safety of the equipment. For example, the operator's access to the inside of the slag discharge mechanism 200 can be restricted by closing one of the side doors 7, thereby reducing the risk of exposure to harmful gases. When the inside of the slag discharge mechanism 200 needs to be inspected or repaired, the provision of multiple side doors 7 can speed up the maintenance and cleaning process of the equipment. The operator can more easily enter the interior of the equipment without moving large structures.

[0041] In the embodiment of the utility model, the slag discharge mechanism 200 is connected to the slag pool mechanism 100 through the pipeline mechanism 10. The pipeline system is used to transfer the waste slag or other slag discharge materials generated by the slag discharge mechanism 200 to the slag pool mechanism 100, ensuring that the slag discharge materials can effectively enter the subsequent processing stage. If the slag discharge mechanism 200 and the slag pool mechanism 100 are located at different heights, the pipeline system can be designed to adapt to this height difference to ensure that the slag discharge materials are smoothly transmitted without obstruction. The provision of a conveying mechanism in the pipeline system can help to more effectively transmit the slag discharge materials and improve the automation and operating efficiency of the system. Specifically, through the conveying mechanism, precise control of the slag discharge materials can be achieved, including the transmission speed, flow rate and direction. This helps to ensure that the slag discharge materials are transmitted according to the designed path and speed. Of course, in other embodiments, the pipeline mechanism may not be provided, but a slag discharge ditch may be dug between the slag discharge mechanism 200 and the slag pool mechanism 100 for communication to achieve the transmission of waste slag or other slag discharge materials.

[0042] The above description is only a preferred embodiment of the utility model and is not intended to limit the utility model. For those skilled in the art, the utility model can have various modifications and changes. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the utility model should be included in the protection scope of the utility model. It should be noted that the structures or components illustrated in the drawings are not necessarily drawn to scale, and the utility model omits the description of known components and processing technologies and processes to avoid unnecessary limitations on the utility model.

Claims

1. A yellow phosphorus production slag fume recovery device, comprising a slag discharge mechanism (200) and a slag pool mechanism (100), characterized in that: The slag pool mechanism (100) comprises a container (1) and a cover plate (2); the container (1) is connected to a smoke extraction pipe (3); the cover plate (2) can be movably covered on the container (1); the container (1) and the cover plate (2) form a sealed container chamber; the slag pool mechanism (100) is connected to the slag discharge mechanism (200); The cover plate (2) comprises a plurality of grid plates (4) spliced ​​together, each grid plate (4) being separated in the middle by a cover steel groove (5), one end of each grid plate (4) being hinged to the cover steel groove (5), and the other end being in a free state, and when the pressure in the accommodating chamber is less than or equal to the atmospheric pressure, each grid plate (4) is sealed and covered with the cover steel groove (5).

2. A yellow phosphorus production slag fume recovery device according to claim 1, characterized in that: When the upward thrust of the smoke in the containing chamber on the cover plate (2) is equal to the sum of the weight of the cover plate (2) and the friction between the cover plate (2) and the containing body (1), a gap is formed between the grid plate (4) and the cover steel groove (5).

3. A yellow phosphorus production slag fume recovery device according to claim 1, characterized in that: The slag discharge mechanism (200) is provided with an exhaust pipe (6).

4. A yellow phosphorus production slag fume recovery device according to claim 3, characterized in that: The exhaust pipe (6) is installed on the top of the slag discharge mechanism (200).

5. A yellow phosphorus production slag fume recovery device according to claim 1, characterized in that: A plurality of side doors (7) are hinged on the side of the slag discharge mechanism (200); when the side doors (7) are closed, the slag discharge mechanism (200) is in a sealed state.

6. A yellow phosphorus production slag fume recovery device according to claim 1, characterized in that: A slag discharge steel trough (8) is provided at the top of the slag discharge mechanism (200), and the top of the slag discharge mechanism (200) is sealed by a plurality of top doors (9), and the top doors (9) are engaged with the slag discharge steel trough (8).

7. A yellow phosphorus production slag fume recovery device according to claim 6, characterized in that: The top door (9) is an upward arched structure.

8. A yellow phosphorus production slag fume recovery device according to claim 5, characterized in that: The side doors (7) are provided with more than two.

9. A yellow phosphorus production slag fume recovery device according to claim 1, characterized in that: The slag discharge mechanism (200) is connected to the slag pool mechanism (100) via a pipeline mechanism (10).

10. A yellow phosphorus production slag fume recovery device according to claim 9, characterized in that: A conveying mechanism is arranged inside the pipeline mechanism (10).

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