Energy-saving and environment-friendly phosphorus burning tower for phosphorus pentoxide production

Abstract

The utility model discloses an energy-saving environment-friendly phosphorus burning tower for phosphorus pentoxide production, which comprises a tower body and a burning spray gun, the tower body comprises a top plate, a burning section and a bottom plate from top to bottom, a combustion-supporting area, a transition area and a burning area are sequentially arranged inside the burning section from bottom to top, two plasma torches are installed on the upper portion of the combustion-supporting area in a staggered mode, and the two plasma torches are arranged in the transition area. The two combustion spray guns are installed on the lower portion of the combustion area close to one side of the transition area, the combustion spray guns and the plasma torches are arranged in a staggered mode, three to four primary air distribution pipes are evenly distributed on the circumference of the combustion area above the combustion spray guns, a smoke exhaust pipe is arranged on the top of the combustion area, and a smoke exhaust control mechanism is arranged on the smoke exhaust pipe. A cooling area is detachably installed at the bottom of the bottom plate, and a slag discharging pipe is arranged at the bottom of the cooling area. According to the device, yellow phosphorus can be fully combusted in the combustion area, the combustion efficiency of the yellow phosphorus is improved, and phosphorus pentoxide flue gas and combustion waste gas entering the lower portion of the combustion-supporting area can be cooled.

Description

Technical Field

[0001] This utility model belongs to the field of phosphorus chemical production technology, specifically relating to an energy-saving and environmentally friendly phosphorus combustion tower for the production of phosphorus pentoxide. Background Technology

[0002] Phosphorus pentoxide is a commonly used raw material and reagent in the chemical industry, widely applied in various fields. High-quality phosphorus pentoxide can also be used to produce high-purity phosphoric acid of various concentrations, especially polyphosphoric acid. Currently, the industrial preparation of phosphorus pentoxide generally adopts the oxidative combustion method: using yellow phosphorus as raw material, the yellow phosphorus is heated and melted and then added to a combustion tower. Dry air is introduced into the combustion tower to react and burn with the yellow phosphorus, generating phosphorus pentoxide flue gas. The phosphorus pentoxide flue gas is then cooled and settled to produce the finished phosphorus pentoxide product. The combustion tower is a key piece of equipment in the production of phosphorus pentoxide. Existing combustion towers include a combustion nozzle and an igniter mounted on the tower body. During operation, the combustion nozzle injects liquid yellow phosphorus into the tower in gaseous form, which is then ignited by the igniter. The resulting phosphorus pentoxide flue gas is condensed to obtain the phosphorus pentoxide product. In this type of combustion tower, the igniter and combustion nozzle are positioned opposite each other, with air distribution ducts located above and below the combustion nozzle. This structure has the following drawbacks: First, the air distribution ducts enter simultaneously from both above and below the combustion nozzle, resulting in uneven oxygen distribution within the tower and insufficient mixing with the phosphorus sprayed from the nozzle. This leads to incomplete combustion of the phosphorus. Second, in existing combustion towers, the area below the combustion nozzle has a lower combustion temperature, causing some phosphorus pentoxide flue gas to linger in this area. Over time, some solid phosphorus pentoxide adheres to the lower part of the tower, affecting combustion efficiency to some extent. Therefore, it is an objective need to develop an energy-saving and environmentally friendly phosphorus combustion tower for phosphorus pentoxide production that has a reasonable structural design, can improve combustion efficiency, and can achieve cooling and temperature reduction at the bottom of the tower. Summary of the Invention

[0003] The purpose of this utility model is to provide an energy-saving and environmentally friendly phosphorus combustion tower for phosphorus pentoxide production with a reasonable structural design that can improve combustion efficiency and achieve cooling at the bottom of the tower.

[0004] The purpose of this utility model is achieved as follows: It includes a tower body and combustion nozzles. The tower body comprises a top plate, a combustion section, and a bottom plate from top to bottom. The combustion section contains, from bottom to top, a combustion-supporting zone, a transition zone, and a combustion zone. The height of the combustion zone is higher than that of the combustion-supporting zone, and the height of the combustion-supporting zone is higher than that of the transition zone. Two plasma torches are alternately installed on the upper part of the combustion-supporting zone. Two combustion nozzles are installed on the lower part of the combustion zone near the transition zone. The combustion nozzles and plasma torches are arranged alternately. Three to four primary air distribution pipes are evenly distributed around the circumference of the combustion zone above the combustion nozzles. A smoke exhaust pipe is installed at the top of the combustion zone, and a smoke exhaust control mechanism is installed on the smoke exhaust pipe. A cooling zone is detachably installed at the bottom of the bottom plate, and a slag discharge pipe is installed at the bottom of the cooling zone, with a slag discharge valve installed on the slag discharge pipe.

[0005] Compared with existing technologies, the advantages of this device are as follows: First, this device optimizes the relative positions of the combustion torch and the plasma torch. The plasma torch is positioned below the combustion torch, and its combustion coverage area is large. During the process of spraying yellow phosphorus from the combustion torch, the contact space between the yellow phosphorus and the plasma torch can be increased, and the contact time can be extended, allowing the yellow phosphorus to burn more fully. During the combustion process, the primary air distribution pipe enters the combustion zone from the top of the combustion torch. The oxygen entering the combustion zone can be evenly distributed and fully contact the burning liquid yellow phosphorus. This helps to improve the combustion efficiency of yellow phosphorus and allows it to burn more completely. The design ensures complete combustion. Furthermore, the exhaust system controls the amount of flue gas emitted, extending the residence time of yellow phosphorus in the combustion zone and allowing for more complete combustion, thus further improving combustion efficiency. Secondly, a cooling zone is installed below the combustion zone. This cooling zone cools the phosphorus pentoxide flue gas and combustion exhaust gas entering the combustion zone, preventing them from adhering to the inner wall of the combustion zone and affecting its combustion efficiency. This invention boasts advantages such as a reasonable structural design, good combustion effect, and the ability to cool the lower part of the tower, making it easy to promote and use. Attached Figure Description

[0006] Figure 1 This is a schematic diagram of the overall structure of this utility model;

[0007] Figure 2 This is a top view of the secondary air distribution duct 8 within the combustion zone 103 in this utility model;

[0008] Figure 3 This is a schematic diagram of the smoke exhaust control mechanism in this utility model;

[0009] Figure 4 This is an enlarged schematic diagram of the cooling zone 6 in this utility model;

[0010] In the diagram: 1-Tower body, 101-Combustion zone, 102-Transition zone, 103-Combustion zone, 2-Combustion torch, 3-Plasma torch, 4-Primary air distribution duct, 5-Exhaust pipe, 51-Modible insert plate, 52-Drive screw, 53-Drive motor, 54-Regulating box, 55-Modular rod, 56-Limit block, 57-Slider, 58-Connecting rod, 6-Cooling zone, 61-Outer shell, 62-Inner shell, 63-Circular flange, 64-Pin, 65-Water cooling cavity, 66-Heat conduction cylinder, 67-Medium inlet, 68-Medium outlet, 69-Cooling coil, 610-Sealing gasket, 7-Slag discharge pipe, 8-Secondary air distribution duct, 9-Tangential air duct. Detailed Implementation

[0011] The present invention will be further described below with reference to the accompanying drawings, but this description is not intended to limit the present invention in any way. Any changes or improvements made based on the teachings of the present invention shall fall within the protection scope of the present invention.

[0012] like Figures 1-4 As shown, this utility model includes a tower body 1 and a combustion torch 2. The tower body 1 includes the tower body itself and refractory material cast and installed inside the tower body. The combustion torch 2 adopts the structure used in the prior art. The tower body 1 includes a top plate, a combustion section, and a bottom plate from top to bottom. The combustion section has a combustion-supporting zone 101, a transition zone 102, and a combustion zone 103 arranged sequentially from bottom to top. The height of the combustion zone 103 is higher than the height of the combustion-supporting zone 101, and the height of the combustion-supporting zone 101 is higher than the height of the transition zone 102. Two plasma torches 3 are alternately installed on the upper part of the combustion-supporting zone 101. The plasma torches 3 adopt the structure used in the prior art. Finished products can be purchased directly according to the functional requirements. There are two combustion nozzles 2, which are installed in the lower part of the combustion zone 103 near the transition zone 102. The combustion nozzles 2 and the plasma torch 3 are arranged alternately. 3 to 4 primary air distribution pipes 4 are evenly distributed around the circumference of the combustion zone 103 above the combustion nozzles 2. The air distribution pipes 3 are equipped with corresponding control valves, pressure gauges and other structural components. A smoke exhaust pipe 5 is provided at the top of the combustion zone 103. A smoke exhaust control mechanism is provided on the smoke exhaust pipe 5. A cooling zone 6 is detachably installed at the bottom of the base plate. A slag discharge pipe 7 is provided at the bottom of the cooling zone 6. A slag discharge valve is provided on the slag discharge pipe 7.

[0013] The working principle of this utility model is as follows: When in use, the plasma torch 3 is working, and the combustion spray gun 2 sprays yellow phosphorus into the combustion zone 103. After entering the combustion zone 103, the yellow phosphorus passes through the transition zone 102 and burns in the area covered by the plasma torch 3. Most of the flue gas after combustion flows back from the transition zone 102 to the combustion zone 103 and mixes with the oxygen entering from the primary air distribution pipe 4 in the combustion zone 103 to achieve complete combustion. The phosphorus pentoxide flue gas produced by combustion will gradually enter the upper part of the combustion zone 103 and be discharged through the exhaust pipe 5. A small part of the phosphorus pentoxide flue gas and exhaust gas produced by combustion in the combustion-supporting zone 101 will flow downward and enter the cooling zone 6. After being cooled by the cooling zone 6, the phosphorus pentoxide formed will accumulate in the slag discharge pipe 7. It is only necessary to open the slag discharge valve periodically to discharge it in time. This invention places the plasma torch 3 below the combustion gun 2. The plasma torch 3 has a large combustion coverage area, which increases the contact space between the yellow phosphorus and the plasma torch 3 during the spraying of yellow phosphorus by the combustion gun 2, prolonging the contact time and allowing the yellow phosphorus to burn completely. During the combustion process, the primary air distribution pipe 4 enters the combustion zone 103 from the top of the combustion gun 2, allowing the oxygen entering the combustion zone 103 to be evenly distributed and fully contact the liquid yellow phosphorus sprayed from the combustion gun 2. This helps to improve the combustion efficiency of yellow phosphorus and allows it to burn completely. In addition, the exhaust mechanism can control the amount of flue gas emitted and prolong the residence time of yellow phosphorus in the combustion zone 103, allowing the yellow phosphorus to burn completely and further improving the combustion efficiency of yellow phosphorus.

[0014] Furthermore, in order to further improve the efficiency of yellow phosphorus combustion, 3 to 4 secondary air distribution pipes 8 are arranged circumferentially on the combustion zone 103 above the primary air distribution pipe 4. The secondary air distribution pipes 8 are arranged alternately with the primary air distribution pipe 4. The secondary air distribution pipes 8 can replenish oxygen to the combustion zone 103 again when the oxygen supply from the primary air distribution pipe 4 is insufficient. This allows the yellow phosphorus carried in the phosphorus pentoxide flue gas to be fully burned, thereby achieving a better combustion effect.

[0015] Preferably, tangential air ducts 9 are installed at the outlet ends of both the primary air distribution duct 4 and the secondary air distribution duct 8. The angle α between the tangential air duct 9 and the corresponding air distribution duct is 120-135°. Oxygen is transported to the combustion zone 103 by the tangential air duct 9. By changing the flow direction of oxygen, oxygen enters the combustion zone 103 along the tangential air duct 9, which can form a swirling airflow, so that it is evenly distributed in the combustion zone 103 and evenly mixed with yellow phosphorus, which is beneficial to improving the combustion efficiency of yellow phosphorus.

[0016] Furthermore, the smoke exhaust control mechanism includes a movable insert plate 51, a transmission screw 52, ​​and a drive motor 53. The drive motor 53 is a structure used in the prior art, and finished products are directly purchased according to the power required. The smoke exhaust pipe 5 is a square tube with a slot machined at the top. The movable insert plate 51 is movably inserted into the square tube through the slot. An adjustment box 54 is installed on the top of the square tube outside the movable insert plate 51. The transmission screw 52 is rotatably installed in the adjustment box 54. The drive motor 53 is installed above the adjustment box 54 and is connected to the transmission screw 52. A movable rod 55 is installed on the top of the movable insert plate 51. The upper end of the movable rod 55 is movably installed on the top of the adjustment box 54. A limit block 56 is installed above the movable rod 55. A slider 57 is slidably installed on the transmission screw 52. The slider 57 is fixedly connected to the movable rod 55 through a connecting rod 58. In use, the drive motor 53 rotates forward or backward. The transmission screw 52 can rotate forward or reverse. During the rotation of the transmission screw 52, ​​the slider 57 can be driven to rise or fall along the transmission screw 52. During the movement of the slider 57, the movable rod 55 and the movable insert plate 51 can be driven to rise and fall up and down through the connecting rod. By controlling the rise and fall of the movable insert plate 51, the size of the exhaust port of the exhaust pipe 5 can be adjusted. By adjusting the size of the exhaust port, the burning time of yellow phosphorus in the combustion zone can be controlled, so that the yellow phosphorus can be fully burned in the combustion zone 103. Preferably, in order to ensure the stability of the movable insert plate 51 during the rise and fall, guide rods are installed on the top of the movable insert plate 51 on both sides of the movable rod 55. The upper end of the guide rod passes through the top of the regulating box 54 and slides with the top of the regulating box 54. The guide rod has a guiding function and can drive the movable insert plate 51 to always keep in a moving state, preventing the phenomenon of deviation during the rise and fall.

[0017] Furthermore, the cooling zone 6 includes an outer shell 61 and an inner shell 62. The top of the outer shell 61 is circumferentially machined with a slot, and the bottom surface of the base plate is machined with a circumferential flange 63. The circumferential flange 63 is movably inserted into the slot. The outer shell 61 and the circumferential flange 63 are connected and positioned by multiple pins 64, making the outer shell 61 and the base plate a detachable connection structure for easy replacement and improved usability. The inner shell 62 is fixedly installed inside the outer shell 61. A water-cooling cavity 65 is provided between the inner shell 62 and the outer shell 61. A vertical recessed groove is machined on the outer wall of the inner shell 62, and a heat-conducting cylinder 66 is sealed and installed within the recessed groove. The heat-conducting cylinder 66 is made of a material with good thermal conductivity and transfers the heat absorbed by the inner shell 62 to the water-cooling cavity 65, improving the cooling effect of the flue gas inside the inner shell 62. The water-cooled cavity 65 has a medium inlet 67 at the bottom and a medium outlet 68 at the top. In use, a cooling medium, which can be cold water or cold air, is supplied into the water-cooled cavity 65 through the medium inlet 67. After entering the water-cooled cavity 65, the cooling medium cools the phosphorus pentoxide flue gas and exhaust gas inside the inner shell 62. After cooling, the phosphorus pentoxide flue gas and exhaust gas form solid powder. The cooling medium absorbs heat in the water-cooled cavity 65, and its temperature rises. Finally, it is discharged through the medium outlet 68. Preferably, in order to further improve the cooling effect on the inner shell 62, a cooling coil 69 is spirally installed on the outer wall of the heat-conducting cylinder 66. Cooling medium is injected into the cooling coil 69, and the inner shell 62 is cooled again by the cooling coil 69. Using two cooling channels to cool the inner shell 62 can significantly improve the cooling efficiency.

[0018] Furthermore, in order to improve the sealing between the outer shell 61 and the base plate and prevent gas leakage, a sealing gasket 610 is provided between the circumferential flange 63 and the slot. The sealing gasket 610 can be made of materials such as rubber or polytetrafluoroethylene used in the prior art.

Claims

1. An energy-saving and environment-friendly phosphorus combustion column for producing phosphorus pentoxide, comprising a column body (1) and a combustion lance (2), characterized in that: The tower body (1) includes a top plate, a combustion section, and a bottom plate from top to bottom. The combustion section has a combustion-supporting zone (101), a transition zone (102), and a combustion zone (103) arranged sequentially from bottom to top. The height of the combustion zone (103) is higher than that of the combustion-supporting zone (101), and the height of the combustion-supporting zone (101) is higher than that of the transition zone (102). Two plasma torches (3) are installed alternately on the upper part of the combustion-supporting zone (101), and there are two combustion nozzles (2) installed on the side near the transition zone (102). In the lower part of the combustion zone (103), the combustion nozzle (2) and the plasma torch (3) are arranged alternately. Three to four primary air distribution pipes (4) are evenly distributed around the combustion zone (103) above the combustion nozzle (2). A smoke exhaust pipe (5) is provided at the top of the combustion zone (103). A smoke exhaust control mechanism is provided on the smoke exhaust pipe (5). A cooling zone (6) is detachably installed at the bottom of the base plate. A slag discharge pipe (7) is provided at the bottom of the cooling zone (6). A slag discharge valve is provided on the slag discharge pipe (7).

2. The energy-saving and environment-friendly phosphorus combustion column for producing phosphorus pentoxide according to claim 1, characterized in that: Three to four secondary air distribution pipes (8) are arranged circumferentially on the combustion zone (103) above the primary air distribution pipe (4), and the secondary air distribution pipes (8) and the primary air distribution pipe (4) are arranged in an alternating manner.

3. The energy-saving and environment-friendly phosphorus combustion tower for producing phosphorus pentoxide according to claim 2, characterized in that: The outlet ends of the primary air distribution pipe (4) and the secondary air distribution pipe (8) are both equipped with tangential air pipes (9), and the included angle α between the tangential air pipe (9) and the corresponding air distribution pipe is 120 to 135°.

4. The energy-saving and environment-friendly phosphorus combustion column for producing phosphorus pentoxide according to claim 1, characterized in that: The smoke exhaust control mechanism includes a movable insert plate (51), a transmission screw (52), and a drive motor (53). The smoke exhaust pipe (5) is a square tube with a socket machined at the top. The movable insert plate (51) is movably inserted into the square tube through the socket. An adjustment box (54) is installed on the top of the square tube outside the movable insert plate (51). The transmission screw (52) is rotatably installed in the adjustment box (54). The drive motor (53) is installed above the adjustment box (54) and is connected to the transmission screw (52) for transmission. A movable rod (55) is installed on the top of the movable insert plate (51). The upper end of the movable rod (55) is movably installed on the top of the adjustment box (54). A limit block (56) is installed above the movable rod (55). A slider (57) is slidably installed on the transmission screw (52). The slider (57) is fixedly connected to the movable rod (55) through a connecting rod (58).

5. The energy-saving and environment-friendly phosphorus combustion tower for producing phosphorus pentoxide according to claim 4, characterized in that: Guide rods are installed on the top of the movable inserts (51) on both sides of the movable rod (55). The upper end of the guide rod passes through the top of the regulating box (54) and slides with the top of the regulating box (54).

6. The energy-saving and environment-friendly phosphorus combustion column for producing phosphorus pentoxide according to claim 1, characterized in that: The cooling zone (6) includes an outer shell (61) and an inner shell (62). The top of the outer shell (61) is circumferentially machined with a slot, and the bottom surface of the base plate is machined with a circumferential flange (63). The circumferential flange (63) is movably inserted into the slot. The outer shell (61) and the circumferential flange (63) are connected and positioned by multiple pins (64). The inner shell (62) is fixedly installed on the inner side of the outer shell (61). A water-cooling cavity (65) is provided between the inner shell (62) and the outer shell (61). A recessed groove is vertically machined on the outer wall of the inner shell (62). A heat-conducting cylinder (66) is sealed and installed in the recessed groove. A medium inlet (67) is provided at the bottom of the water-cooling cavity (65), and a medium outlet (68) is provided at the top.

7. The energy-saving and environment-friendly phosphorus combustion tower for producing phosphorus pentoxide according to claim 6, characterized in that: Cooling coils (69) are spirally installed on the outer wall of the heat-conducting cylinder (66).

8. The energy-saving and environment-friendly phosphorus combustion column for producing phosphorus pentoxide according to claim 6, characterized in that: A sealing gasket (610) is provided between the circumferential flange (63) and the slot.

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