Granulation tail gas dust removal tower

Abstract

The utility model discloses a granulation tail gas dust removal tower which is characterized in that an inner cylinder is arranged in a tower body, and a supporting assembly is fixedly arranged above the tower body; the upper section of the inner cylinder is fixedly mounted on the supporting assembly, and the lower section of the inner cylinder is connected with the water curtain; the efficient blade demister is fixedly installed on the lower sealing plate, and the lower sealing plate is fixedly installed on the supporting assembly. One end of the downcomer is mounted on the lower sealing plate, and the other end leads into the inner cylinder; the upper sealing plate is fixedly mounted on the efficient blade demister; the blade backwashing device is mounted at the upper section of the inner cylinder and comprises two parts, one part is positioned on a main spraying device in front of a blade, and the other part is introduced into a blade box and is positioned on an auxiliary spraying device right above the blade; and meanwhile, a three-stage spray washing device is fixedly mounted in the inner cylinder and is positioned below the efficient blade demister. The urea prilling tower solves the problems that a traditional urea prilling tower is low in washing efficiency, high in requirement for circulating water amount, substandard in dust and ammonia emission and the like.

Description

Technical Field

[0001] The utility model belongs to the field of tail gas purification and dust removal, and particularly relates to a granulation tail gas dust removal tower. Background Art

[0002] In the chemical industry, as the core equipment for producing granular urea, the operating efficiency and environmental protection performance of the urea granulation tower are directly related to the quality of urea products and the sustainability of the production process.

[0003] Firstly, traditional urea granulation towers rely on natural ventilation for heat dissipation and tail gas emission. During the granulation process, the dust concentration remains high, and particulate matter emissions seriously exceed the standards. When the high-concentration dust mixes with water vapor, it forms an aerosol, resulting in an obvious trailing phenomenon during tail gas emission.

[0004] Even more severely, the dust in the granulation tower is rich in ammonia, and the ammonia content far exceeds the safety and environmental protection standards. The untreated ammonia-containing dust directly discharged into the atmosphere not only aggravates air pollution but also poses a threat to the health of surrounding residents, especially significantly damaging the respiratory system and seriously affecting the daily living quality of residents.

[0005] In addition, the granulation tail gas also carries a large amount of atomized urea droplets. These tiny droplets are prone to cause secondary pollution in the environment, corrode surrounding buildings, steel materials stacked outdoors, etc., increasing the enterprise's maintenance costs and possibly causing long-term adverse effects on the surrounding ecological environment.

[0006] Currently, a wet treatment technology with reverse spray washing and baffle demisting structures has been applied to the treatment of urea granulation tower tail gas, but the actual effect is not ideal. This technology has problems such as low washing efficiency, high requirement for circulating water volume, still unqualified dust and ammonia emissions, poor demisting effect, and serious entrainment of mist droplets, and the tail gas trailing phenomenon is still significant. Summary of the Invention

[0007] In order to overcome the problems existing in traditional urea granulation towers, such as low washing efficiency, high requirement for circulating water volume, still unqualified dust and ammonia emissions, etc., the utility model provides a granulation tail gas dust removal tower to improve the environmental protection performance of the urea granulation tower and ensure the green and sustainable development of the production process.

[0008] The technical solution of the utility model is as follows: A granulation tail gas dust removal tower includes a tower body. Its characteristic is that an inner cylinder is arranged in the tower body. The upper section of the inner cylinder is fixedly installed on the support assembly, and the support assembly is fixedly installed above the tower body; the lower section of the inner cylinder is connected to the water curtain; the lower sealing plate is fixedly installed on the support assembly, and the high-efficiency vane demister is fixedly installed on the lower sealing plate. The high-efficiency vane demister is composed of vane boxes, and the vanes are installed in the vane boxes; one end of the downcomer is installed on the lower sealing plate, and the other end leads to the inside of the inner cylinder; the upper sealing plate is fixedly installed on the high-efficiency vane demister; the vane backwashing device is installed in the upper section of the inner cylinder. The vane backwashing device includes two parts. One part is the main spraying device located in front of the vane, and the other part is the auxiliary spraying device introduced into the vane box and located directly above the vane; a three-stage spray washing device is fixedly installed in the inner cylinder, below the high-efficiency vane demister; the steam flushing device is installed above the tower body, the outlet position of the nozzle is in the vane box, and the steam port direction of the nozzle is vertically downward, so that the steam moves from top to bottom.

[0009] Further, the three-stage spray washing device is composed of a spray main pipe, spray branch pipes, and nozzles. The spraying direction of the nozzles is vertically downward.

[0010] Further, the main spraying device is composed of a flushing main pipe, flushing branch pipes, and three layers of nozzles arranged vertically; the nozzles of the main spraying device are in the same direction as the fluid direction; the auxiliary spraying device is composed of a flushing main pipe and flushing branch pipes. There are direct sprays at the openings of the flushing branch pipes, and the spraying direction is vertically downward. The scale is further flushed through the pressure and self-weight of the fluid.

[0011] The utility model has the following beneficial effects

[0012] 1. The spray washing device is provided with three-stage spraying. Compared with single-stage spraying, the distribution of liquid droplets in the gas flow channel is more uniform, and the gas-liquid ratio is effectively increased, and the contact area between gas and liquid is increased, thereby improving the absorption of ammonia.

[0013] 2. By setting the inner cylinder, the volume of the gas flow channel is reduced. Under the condition of ensuring the same gas-liquid ratio, the volume of the effective channel is reduced, thereby reducing the amount of circulating water required.

[0014] 3. A water curtain is added to block the liquid droplets sprayed by the spray washing device, prevent the liquid droplets from splashing and corroding the equipment below, and at the same time recover the circulating water, effectively reducing the amount of circulating water used.

[0015] 4. One part of the vane backwashing device is in front of the vane, along the direction of fluid passage, better contacting the scale to prevent the high-efficiency vane demister from being blocked; the other part is set directly above the vane, and the scale is further flushed through the pressure and self-weight of the fluid. Description of the Drawings

[0016] Figure 1It is a schematic structural diagram of the granulation tail gas dust removal tower of the present utility model;

[0017] Figure 2 It is a schematic structural diagram of the spray washing device;

[0018] Figure 3 It is a schematic structural diagram of the blade backwashing device;

[0019] The reference numerals are as follows: 1 - tower body; 2 - water curtain; 3 - inner cylinder; 4 - support assembly; 5 - downcomer; 6 - lower sealing plate; 7 - upper sealing plate; 8 - steam flushing device; 9 - high-efficiency vane demister; 10 - blade backwashing device; 11 - spray washing device; 12 - main spray pipe; 13 - spray branch pipe; 14 - nozzle; 15 - flushing main pipe; 16 - flushing branch pipe; 17 - three-layer nozzle. Detailed implementation manners

[0020] The present utility model reforms the top of the granulation tower, without increasing the height of the granulation tower, with low equipment transformation cost and convenient inspection and maintenance.

[0021] As Figure 1 shown, a granulation tail gas dust removal tower of the present utility model mainly consists of components such as tower body 1, water curtain 2, inner cylinder 3, support assembly 4, downcomer 5, lower sealing plate 6, upper sealing plate 7, steam flushing device 8, high-efficiency vane demister 9, blade backwashing device 10, spray washing device 11, etc.

[0022] The support assembly 4 is fixedly installed above the tower body 1, reforming the top of the granulation tower, without increasing the height of the granulation tower, with low equipment transformation cost and convenient inspection and maintenance.

[0023] The high-efficiency vane demister 9 is fixedly installed on the lower sealing plate 6 and consists of vanes and vane boxes, and the vanes are installed in the vane boxes; one end of the downcomer 5 is installed on the lower sealing plate 6, and the other end leads to the inside of the inner cylinder 3. The lower sealing plate 6 is fixedly installed on the support assembly 4, and the upper sealing plate 7 is fixedly installed on the high-efficiency vane demister 9; the vane box is a hexahedron structure, the shape of the lower sealing plate 6 is an outer circle with an inner hexagon, and the shape of the upper sealing plate 7 is a whole hexagonal plate.

[0024] The upper section of the inner cylinder 3 is fixedly installed on the support assembly 1, and the lower section is connected to the water curtain 2. At the same time, the spray washing device 11 is installed in the inner cylinder 3. Setting the inner cylinder reduces the volume of the gas flow channel, ensuring that under the condition of the same gas-liquid ratio, the volume of the effective channel is reduced, thereby reducing the amount of circulating water required.

[0025] The spray washing device 11 is provided with three-stage spraying, located below the high-efficiency vane demister 9, as Figure 2As shown in the figure, it is composed of a main spray pipe 12, spray branch pipes 13, and nozzles 14, and the spraying direction of the nozzles is vertically downward. Three - stage spraying is set, so that the distribution of liquid droplets in the gas - flowing channel is more uniform, effectively improving the gas - liquid ratio and increasing the contact area between gas and liquid, thereby enhancing the absorption of ammonia.

[0026] The blade back - flushing device 10 is installed in the upper section of the inner cylinder 3 and consists of two parts: the main spraying device and the secondary spraying device. Figure 1 The one with three layers of nozzles 17 arranged vertically in the vertical direction led out from it is the main spraying device. Going further up, the one introduced into the blade box is the secondary spraying device.

[0027] As Figure 3 As shown in the figure, the main spraying device is composed of a flushing main pipe 15, flushing branch pipes 16, and three layers of nozzles 17. The three layers of nozzles 17 of the main spraying device are along the fluid - passing direction, better contacting the scale to prevent the high - efficiency blade demister 9 from being blocked. The secondary spraying device (without nozzles) is composed of a flushing main pipe 15 and flushing branch pipes 16, and directly sprays through the openings on the flushing branch pipes 16. The spraying direction is vertically downward, and the scale is further flushed through the pressure and self - weight of the fluid.

[0028] The steam flushing device 8 is fixed above the tower body 1 and consists of a main spray pipe and spray branch pipes. The outlet position of the nozzle is in the blade box, and the steam port direction of the nozzle is vertically downward, so that the steam moves from top to bottom, the heating is more uniform, the dissolution efficiency of the scale is improved, and it is beneficial for flushing.

Claims

1. A granulation tail gas dust removal tower, comprising a tower body (1), characterized in that, An inner cylinder (3) is provided inside the tower body (1). The upper section of the inner cylinder is fixedly installed on the support assembly (4), and the support assembly (4) is fixedly installed above the tower body (1). The lower section of the inner cylinder is connected to the water curtain (2). The lower sealing plate (6) is fixedly installed on the support assembly (4), and the high-efficiency vane demister (9) is fixedly installed on the lower sealing plate (6). The high-efficiency vane demister is composed of vane boxes, and the vanes are installed in the vane boxes. One end of the downcomer (5) is installed on the lower sealing plate (6), and the other end leads into the inner cylinder. The upper sealing plate (7) is fixedly installed on the high-efficiency vane demister (9). The vane backwashing device (10) is installed in the upper section of the inner cylinder. The vane backwashing device (10) includes two parts. One part is the main spraying device located directly in front of the vanes, and the other part is the auxiliary spraying device introduced into the vane box and located directly above the vanes. A three-stage spray washing device (11) is fixedly installed in the inner cylinder and is located below the high-efficiency vane demister (9). The steam flushing device (8) is installed above the tower body (1). The outlet position of the nozzle is in the vane box, and the steam port direction of the nozzle is vertically downward, so that the steam moves from top to bottom.

2. The granulation tail gas dust removal tower according to claim 1, characterized in that, The three-stage spray washing device (11) is composed of a spray main pipe (12), spray branch pipes (13), and nozzles (14). The spraying direction of the nozzles is vertically downward.

3. The granulation tail gas dust removal tower according to claim 2, characterized in that The main spraying device is composed of a flushing main pipe (15), flushing branch pipes (16), and three layers of nozzles (17) arranged vertically. The three layers of nozzles (17) of the main spraying device are in the same direction as the fluid direction. The auxiliary spraying device is composed of a flushing main pipe (15) and flushing branch pipes (16). Openings are directly sprayed on the flushing branch pipes (16), and the spraying direction is vertically downward.

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