A compound fertilizer process tail gas washing tower

Abstract

The utility model relates to tail gas washing technical field, concretely is a kind of compound fertilizer process tail gas washing tower, including venturi, washing tower and circulating unit, venturi is located in washing tower one side, venturi includes the convergent pipe, throat pipe, diffuser pipe connected in proper order, convergent pipe is communicated with tail gas discharge pipeline, throat pipe upper portion is horizontally provided with transverse spray pipe along left and right direction, the bottom of transverse spray pipe is communicated with several longitudinal spray pipes along horizontal direction and is arranged, the bottom of longitudinal spray pipe is provided with spray head, diffuser pipe is communicated with the bottom of washing tower;Throat pipe upper portion is further equipped with helical flow guide, lower portion is equipped with anti-blocking slag discharge structure;Washing tower is sequentially provided with exhaust pipe, demister, main spray pipe, filler layer from top to bottom;Circulating unit includes liquid storage tank, circulating pump and connecting pipeline, liquid storage tank is communicated with transverse spray pipe and main spray pipe respectively by circulating pump.The scheme overcomes the defect that compound fertilizer tail gas washing tower gas-liquid mixing is not sufficient in prior art, is easy to block.

Description

Technical Field

[0001] This utility model relates to the field of exhaust gas scrubbing technology, specifically to an exhaust gas scrubbing tower for compound fertilizer processes. Background Technology

[0002] Compound fertilizer production is a complex chemical process involving multiple stages such as raw material mixing, granulation, drying, and cooling. These stages generate large amounts of waste gas containing various pollutants, primarily including dust, ammonia, fluorides, sulfides, and small amounts of volatile organic compounds. If this waste gas is emitted directly without treatment, it will not only pollute the surrounding environment but may also affect the health of workers and nearby residents.

[0003] In response to the characteristics of compound fertilizer waste gas, the industry has developed various treatment methods, including dry treatment, wet treatment, and biological treatment, each with its own applicable scenarios and advantages and disadvantages. Wet scrubbing is one of the most commonly used methods for treating compound fertilizer waste gas. This method uses a scrubbing tower to fully contact the waste gas with the scrubbing liquid, removing pollutants through physical absorption and chemical reaction. Wet scrubbing has advantages such as high treatment efficiency and strong adaptability. Existing technologies combine Venturi tubes and scrubbing towers for wet treatment of waste gas, as shown in patent CN222518143U, a flue gas cooling and dust removal system. This involves adding a Venturi cooling and dust collector at the front end of a primary scrubbing tower, achieving efficient cooling and preliminary dust removal of the flue gas. However, this method has the following drawbacks: The Venturi inlet throat only has a single spray water system, resulting in short contact time and uneven mixing between the exhaust gas and the scrubbing liquid, leading to low removal efficiency of dust and soluble pollutants; the sticky dust in the compound fertilizer exhaust gas easily adheres to the inner wall of the Venturi throat, causing pipe blockage with long-term operation, requiring frequent shutdowns for cleaning and affecting production continuity; and the mist droplets carried by the exhaust gas after scrubbing are not effectively separated, increasing the load on subsequent treatment equipment and easily causing secondary pollution.

[0004] Therefore, there is an urgent need to design a compound fertilizer process tail gas scrubbing tower that can improve gas-liquid mixing efficiency, prevent pipeline blockage, and has droplet separation function to overcome the shortcomings of existing technologies. Utility Model Content

[0005] The purpose of this invention is to overcome the shortcomings of insufficient gas-liquid mixing and easy clogging in the existing compound fertilizer tail gas scrubbing tower, and to provide a compound fertilizer process tail gas scrubbing tower that achieves efficient tail gas purification and stable equipment operation by optimizing the Venturi structure and internal components.

[0006] To solve the above problems, the technical solution adopted by this utility model is a compound fertilizer process tail gas scrubbing tower, including a Venturi tube (1), a scrubbing tower (2), and a circulation unit (3). The Venturi tube (1) is located on one side of the scrubbing tower (2). The Venturi tube (1) includes a contraction tube (11), a throat (12), and a diffuser (13) connected in sequence. The contraction tube (11) is connected to the tail gas emission pipe. A horizontal spray pipe (14) is horizontally arranged at the upper part of the throat (12) in the left-right direction. The bottom of the horizontal spray pipe (14) is connected to several vertical spray pipes (15) arranged in the horizontal direction. The bottom of the spray pipe (15) is provided with a nozzle (16), and the diffuser pipe (13) is connected to the bottom of the washing tower (2); the upper part of the throat pipe (12) is also provided with a spiral guide (17), and the lower part is provided with an anti-clogging slag discharge structure (18); the washing tower (2) is provided with an exhaust pipe (21), a demister (22), a main spray pipe (23), and a packing layer (24) from top to bottom; the circulation unit (3) includes a liquid storage tank (31), a circulation pump (32), and a connecting pipe (33), and the liquid storage tank (31) is connected to the transverse spray pipe (14) and the main spray pipe (23) respectively through the circulation pump (32).

[0007] Furthermore, the anti-clogging slag discharge structure (18) includes a slag discharge port (181) and a detachable sealing cover plate (182). The connection between the slag discharge port (181) and the lower inner wall of the throat pipe (12) is an arc-shaped transition surface to prevent dust accumulation. The sealing cover plate (182) is made of wear-resistant and corrosion-resistant material.

[0008] Furthermore, the spray angle of the nozzle (16) is 60-90°, and there is a 10-15% overlap in the spray range of adjacent nozzles, ensuring that the washing liquid is fully covered in the cross-section of the throat (12).

[0009] Furthermore, a flange connection structure is provided between the shrink tube (11) and the exhaust gas pipe, and a corrosion-resistant sealing gasket is provided on the flange contact surface.

[0010] Furthermore, the exhaust pipe (21) is equipped with an intelligent detection system (25), which includes a concentration monitoring sensor (251) and a data acquisition unit (252) for real-time monitoring of the pollutant concentration in the purified exhaust gas.

[0011] Furthermore, the data acquisition unit (252) is used to collect the pollutant concentration, operating parameters, and total emissions of the purified exhaust gas. The operating parameters include the liquid-to-gas ratio, pH value, and temperature.

[0012] Furthermore, the storage tank (31) is equipped with an automatic control system, which includes a liquid level sensor (34) and an automatic water replenishment device (35). The liquid level sensor (34) and the automatic water replenishment device (35) are linked to achieve automatic maintenance of the liquid level and stable operation of the system.

[0013] Furthermore, the bottom of one side of the washing tower (2) is connected to a drain pipe (27) with a drain valve (26), and the drain valve (26) is opened periodically to discharge the deposited waste residue.

[0014] Furthermore, compared with existing technologies, the beneficial effects of this solution are: 1. Improved gas-liquid mixing enhances processing efficiency: This invention adds a spiral guide to the venturi tube, combined with a multi-angle overlapping spray atomizing nozzle, to form a spiral mixed airflow between the exhaust gas and the washing liquid, extending the contact time and improving the removal rate of dust and soluble pollutants, thus solving the problem of insufficient gas-liquid mixing in existing equipment.

[0015] 2. Extend equipment life and avoid blockage: The anti-blockage slag discharge structure at the bottom of the venturi tube reduces dust accumulation through the arc transition surface, and the sealing cover can be opened regularly to clean the waste residue, effectively avoiding pipeline blockage and extending the continuous operation cycle of the equipment to more than 60 days.

[0016] 3. Energy saving and environmental protection: The packing layer and baffle plate demister layer installed in the scrubbing tower realize secondary purification of exhaust gas and separation of mist droplets. After purification, the moisture content of exhaust gas is reduced to below 10%, which meets the requirements of energy saving and environmental protection. Attached Figure Description

[0017] Figure 1 This is an overall structural diagram of a compound fertilizer process tail gas scrubbing tower according to the present invention.

[0018] In the diagram: 1-Venturi tube, 11-Contraction tube, 12-Throat, 13-Diffuser, 14-Horizontal spray pipe, 15-Longitudinal spray pipe, 16-Spray head, 17-Spiral guide, 18-Anti-clogging slag discharge structure, 181-Slag discharge port, 182-Sealing cover, 2-Scrubbing tower, 21-Exhaust pipe, 22-Demister, 23-Main spray pipe, 24-Packing layer, 25-Intelligent detection system, 251-Concentration monitoring sensor, 252-Data acquisition unit, 26-Drain valve, 27-Drain pipe, 3-Circulation unit, 31-Storage tank, 32-Circulation pump, 33-Connecting pipe, 34-Level sensor, 35-Automatic water replenishment device. Detailed Implementation

[0019] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0020] Implementation, for example, attached Figure 1 As shown: This embodiment is a compound fertilizer process tail gas scrubbing tower, including a Venturi tube 1, a scrubbing tower 2, and a circulation unit 3.

[0021] A venturi tube 1 is installed on one side of the scrubbing tower 2. The venturi tube 1 includes a contraction tube 11, a throat 12, and a diffuser 13 connected in sequence. The contraction tube 11 is connected to the exhaust gas emission pipe. A horizontal spray pipe 14 is horizontally arranged at the top of the throat 12 in the left-right direction. Several vertical spray pipes 15 are connected at the bottom of the horizontal spray pipes 14 in the horizontal direction. A nozzle 16 is installed at the bottom of the vertical spray pipes 15. The diffuser 13 is connected to the bottom of the scrubbing tower 2. A spiral guide 17 is also provided at the top of the throat 12, and an anti-clogging slag discharge structure 18 is provided at the bottom. The anti-clogging slag discharge structure 18 includes a slag discharge port 181 and a removable sealing cover 182. The connection between the slag discharge port 181 and the lower inner wall of the throat 12 is an arc-shaped transition surface to prevent dust accumulation. The sealing cover 182 is made of wear-resistant and corrosion-resistant material. Slag discharge and sealing cover replacement are performed regularly.

[0022] When the exhaust gas is scrubbed, it enters the contraction pipe 11 through the exhaust gas discharge pipe. The contraction pipe 11 further delivers the exhaust gas to the throat pipe 12, and then to the bottom of the tower body 2 through the diffuser pipe 13. A flange connection structure is provided between the contraction pipe 11 and the exhaust gas discharge pipe. The flange contact surface is equipped with a corrosion-resistant sealing gasket, which facilitates the quick installation and maintenance of the equipment.

[0023] In this design, nozzle 16 uses a spiral nozzle with a spray angle of 60-90°. The spray range of adjacent nozzles overlaps by 10-15%, ensuring that the washing liquid is fully covered within the cross-section of the throat 12, thus achieving preliminary purification.

[0024] After the exhaust gas enters the scrubbing tower 2, it flows from bottom to top. The scrubbing tower 2, from top to bottom, consists of an exhaust pipe 21, a demister 22, a main spray pipe 23, and a packing layer 24. The packing layer 24 uses PP multi-faceted hollow spheres or PVC corrugated packing, which has a large specific surface area, extending the gas-liquid contact time and improving absorption efficiency. In this design, the main spray pipe 23 can also be configured with spiral nozzles or hollow conical nozzles to ensure that droplets cover the entire tower cross-section, preventing purification failure due to dry areas. The demister 22 uses a baffle or swirl plate design, with a separation efficiency >95%, preventing secondary pollution caused by droplet entrainment. The exhaust pipe 21 is equipped with an intelligent detection system 25, which includes a concentration monitoring sensor 251 and a data acquisition unit 252 for real-time monitoring of pollutant concentrations in the purified exhaust gas. The data acquisition unit 252 collects pollutant concentrations, operating parameters, and total emissions of the purified exhaust gas. Operating parameters include the liquid-to-gas ratio, pH value, and temperature.

[0025] In this scheme, the washing liquid is a mixture of water and chemical reagents. The formula of the washing liquid varies depending on the composition of the waste gas. The washing liquid is stored in a dedicated storage tank 31 and transported to the spray zone by a circulation pump 32. In the spray zone, the washing liquid is evenly sprayed through nozzles, contacting the waste gas and absorbing pollutants. The washing liquid that has absorbed pollutants flows along the inner wall of the tower to the bottom of the washing tower 2. A drain pipe 27 with a drain valve 26 is connected to one side of the bottom of the washing tower 2. The drain valve 26 is opened periodically to discharge the washing liquid that has absorbed pollutants. A filter device can also be installed on the drain pipe 27 to perform secondary treatment such as filtration on the washing liquid before it flows back into the storage tank 31 for reuse, forming a closed-loop circulation system.

[0026] The circulation unit 3 includes a storage tank 31, a circulation pump 32, and a connecting pipe 33. The storage tank 31 is connected to the horizontal spray pipe 14 and the main spray pipe 23 via the circulation pump 32. The storage tank 31 is equipped with an automatic control system, which includes a liquid level sensor 34 and an automatic water replenishment device 35. The liquid level sensor 34 and the automatic water replenishment device 35 are linked. When the liquid level sensor 34 detects that the amount of washing liquid in the storage tank 31 is inconsistent with the preset amount, the automatic water replenishment device 35 injects a certain amount of washing liquid into the storage tank 31 through the pipe, thereby achieving automatic maintenance of the liquid level and stable operation of the system.

[0027] Working principle: The exhaust gas from the compound fertilizer process enters the contraction pipe 11 through the exhaust pipe, then passes through the throat pipe 12. In the throat pipe 12, the spray system sprays washing liquid through the nozzles 16. Under the action of the spiral guide 17, the exhaust gas and washing liquid form a spiral upward airflow, achieving preliminary purification. Subsequently, the airflow enters the diffuser 13 and finally enters the bottom of the scrubbing tower 2. Then, the airflow moves upward and enters the packing layer 24, while the main spray pipe 23 sprays washing liquid. The airflow and the washing liquid on the surface of the packing further contact, removing residual pollutants. Finally, after the mist droplets are separated by the demister 22, it is discharged from the exhaust pipe 21. The concentration monitoring sensor 251 monitors the emission concentration in real time, the drain valve 26 is opened periodically to discharge the waste liquid at the bottom of the scrubbing tower 2, and the sealing cover 182 is opened periodically to discharge slag.

[0028] This solution employs a four-stage treatment process—"Venturi preliminary purification + packing layer absorption + spray washing + demisting"—to improve the gas-liquid mixing efficiency during the treatment of exhaust gas from compound fertilizer production, prevent pipeline blockage, and provide droplet separation functionality.

[0029] The above descriptions are merely embodiments of this utility model, and common knowledge regarding specific structures and characteristics is not elaborated upon here. It should be noted that those skilled in the art can make various modifications and improvements without departing from the structure of this utility model, and these should also be considered within the scope of protection of this utility model. These modifications will not affect the effectiveness of the implementation of this utility model or the practicality of the patent. The scope of protection claimed in this application shall be determined by the content of its claims, and the specific embodiments described in the specification can be used to interpret the content of the claims.

Claims

1. A compound fertilizer process tail gas scrubbing tower, comprising a venturi tube (1), a scrubbing tower (2), and a circulation unit (3), characterized in that: The Venturi tube (1) is located on one side of the scrubbing tower (2). The Venturi tube (1) includes a contraction tube (11), a throat (12), and a diffuser (13) connected in sequence. The contraction tube (11) is connected to the exhaust gas discharge pipe. A horizontal spray pipe (14) is horizontally arranged at the top of the throat (12) in the left-right direction. Several vertical spray pipes (15) arranged in the horizontal direction are connected to the bottom of the horizontal spray pipes (14). A nozzle (16) is arranged at the bottom of the vertical spray pipes (15). The diffuser (13) is connected to... The bottom of the washing tower (2); the upper part of the throat pipe (12) is also provided with a spiral guide (17), and the lower part is provided with an anti-clogging slag discharge structure (18); the washing tower (2) is provided with an exhaust pipe (21), a demister (22), a main spray pipe (23), and a packing layer (24) from top to bottom; the circulation unit (3) includes a storage tank (31), a circulation pump (32) and a connecting pipe (33), and the storage tank (31) is connected to the transverse spray pipe (14) and the main spray pipe (23) respectively through the circulation pump (32).

2. The compound fertilizer process tail gas scrubbing tower according to claim 1, characterized in that: The anti-clogging slag discharge structure (18) includes a slag discharge port (181) and a detachable sealing cover plate (182). The connection between the slag discharge port (181) and the lower inner wall of the throat pipe (12) is an arc-shaped transition surface to prevent dust accumulation. The sealing cover plate (182) is made of wear-resistant and corrosion-resistant material.

3. The compound fertilizer process tail gas scrubbing tower according to claim 1, characterized in that: The spray angle of the nozzle (16) is 60-90°, and there is a 10-15% overlap in the spray range of adjacent nozzles, ensuring that the washing liquid is fully covered in the cross-section of the throat (12).

4. The compound fertilizer process tail gas scrubbing tower according to claim 1, characterized in that: The contraction tube (11) is connected to the exhaust gas pipe by a flange connection structure, and the flange contact surface is provided with a corrosion-resistant sealing gasket.

5. The compound fertilizer process tail gas scrubbing tower according to claim 1, characterized in that: The exhaust pipe (21) is equipped with an intelligent detection system (25), which includes a concentration monitoring sensor (251) and a data acquisition unit (252) for real-time monitoring of the pollutant concentration in the purified exhaust gas.

6. The compound fertilizer process tail gas scrubbing tower according to claim 5, characterized in that: The data acquisition unit (252) is used to collect the pollutant concentration, operating parameters, and total emissions of the purified exhaust gas. The operating parameters include the liquid-to-gas ratio, pH value, and temperature.

7. The compound fertilizer process tail gas scrubbing tower according to claim 1, characterized in that: The storage tank (31) is equipped with an automatic control system, which includes a liquid level sensor (34) and an automatic water replenishment device (35). The liquid level sensor (34) and the automatic water replenishment device (35) are linked to achieve automatic maintenance of the liquid level and stable operation of the system.

8. The compound fertilizer process tail gas scrubbing tower according to claim 1, characterized in that: The bottom of one side of the washing tower (2) is connected to a drain pipe (27) with a drain valve (26), and the drain valve (26) is opened periodically to discharge the deposited waste residue.

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