Energy-saving absorption tower for recovering ammonia from glycine tail gas

Abstract

The present disclosure relates to the technical field of absorption towers, and one embodiment of the present disclosure provides an energy-saving absorption tower for recovering ammonia in a glycine tail gas, which comprises a tower body and a bottom collecting box arranged at the bottom of the tower body, a cooling assembly arranged in the bottom collecting box, and a heat exchange circulating spray assembly arranged on the tower body, wherein the heat exchange circulating spray assembly comprises a heat exchange box arranged outside the tower body, a heat exchange layer arranged around the inner wall of the tower body, a plurality of circulating cavities arranged around the heat exchange layer, a pair of separation cavities arranged in the heat exchange layer, and a circulating pipeline connected between the outer wall of the tower body and the heat exchange box, and a filler layer arranged at the upper end of the tower body. Through the above technical solution, the technical problem of high operating cost caused by the double high energy consumption of the high-power pump driving the high-frequency circulation of the absorbent to strengthen the contact in the absorption stage and the external source heating to improve the ammonia desorption efficiency in the analysis stage is solved.

Description

Technical Field

[0001] The embodiments disclosed herein relate to the technical field of absorption towers, specifically to an energy-saving absorption tower for ammonia recovery from glycine tail gas. Background Technology

[0002] The production of glycine generates ammonia-containing tail gas. Direct emission of this gas not only wastes ammonia resources but also pollutes the environment. Absorption towers, as the core equipment for ammonia recovery, capture ammonia through contact between the absorbent and the tail gas. Their recovery efficiency and energy consumption directly determine environmental benefits and production costs. With the green and low-carbon development of the chemical industry, the energy-saving deficiencies of existing ammonia recovery absorption towers are becoming increasingly apparent.

[0003] Traditional absorption towers often employ high-flow-rate absorbent circulation or high-temperature heating and desorption processes to ensure ammonia absorption rates. During the absorption phase, a high-power pump drives the absorbent for high-frequency circulation to enhance contact; during the desorption phase, external heating is relied upon to improve ammonia desorption efficiency. This dual high energy consumption results in persistently high operating costs. While some simplified absorption towers streamline the process, the counter-current contact between the absorbent and the exhaust gas is insufficient, requiring extended contact time to compensate for efficiency, further increasing energy consumption.

[0004] High energy consumption contradicts current energy-saving production requirements, and external heating easily causes absorbent degradation, increasing consumable costs; the operation of high-power equipment also increases equipment wear and tear and maintenance costs. Meanwhile, excessive energy consumption limits the widespread adoption of ammonia recovery devices in small and medium-sized glycine enterprises, exacerbating environmental pressures. Therefore, developing energy-saving absorption towers for ammonia recovery from glycine tail gas, addressing the pain point of poor energy-saving performance, has become an urgent industry need. Utility Model Content

[0005] To overcome the above-mentioned defects, the embodiments of this disclosure provide an energy-saving absorption tower for ammonia recovery from glycine tail gas, which solves the technical problem that the absorption stage requires a high-power pump to drive the absorbent to circulate at high frequency to enhance contact, and the desorption stage relies on external heating to improve ammonia desorption efficiency, resulting in high operating costs due to the dual high energy consumption.

[0006] According to one aspect, at least one embodiment of this disclosure provides an energy-saving absorption tower for ammonia recovery from glycine tail gas, comprising: The tower body and the bottom collection box, wherein the bottom collection box is located at the bottom of the tower body; A cooling component, wherein the cooling component is disposed in the bottom collection box; A heat exchange circulating spray assembly is disposed on the tower body; The heat exchange circulating spray assembly includes a heat exchange box, which is disposed on the outside of the tower body. A heat exchange layer is disposed around the inner wall of the tower body. Several circulation chambers are opened around the inner wall of the heat exchange layer. A pair of partition chambers are opened within the heat exchange layer. The circulation chambers are separated by the partition chambers. A circulation pipe is connected between the outer wall of the tower body and the heat exchange box. A packing layer is disposed at the upper end of the tower body.

[0007] As a further technical solution, one of the circulating pipes is connected to the heat exchange box via a water pump, and a pair of circulating pipes are respectively located at the top and bottom of the heat exchange box. The bottom of the heat exchange box is provided with an inlet pipe, and the top of the heat exchange box is provided with an outlet pipe.

[0008] As a further technical solution, a spiral heat exchange tube is provided inside the heat exchange box, and the two ends of the spiral heat exchange tube are respectively connected to the liquid inlet pipe and the liquid outlet pipe. An inner ring pipe is provided around the top of the tower body.

[0009] As a further technical solution, a number of spray nozzles are arranged around the inner ring pipe, one end of the liquid outlet pipe is connected to an inlet pipe, the upper end of the inlet pipe is connected to the inner ring pipe, and a water pump is arranged on the outside of the bottom collection box, the output end of the water pump is connected to the lower end of the inlet pipe.

[0010] As a further technical solution, a switching control valve is provided at one end of the liquid outlet pipe and the output end of the water pump, and a concentration detection head is provided on the bottom surface of the bottom collection tank. The water pump can reuse dilute acid solution whose concentration does not meet the standard.

[0011] According to another aspect, in at least one embodiment of the present invention, the cooling component includes a heat-conducting plate disposed inside the side wall of the bottom collection box, and a plurality of heat exchange rings are connected in the heat-conducting plate, the heat exchange rings being evenly distributed around the inside of the bottom collection box.

[0012] As a further technical solution, the heat-conducting plate is provided with heat dissipation fins at its outer end, the bottom collection box is provided with a dust cover, several cooling fans are installed on the outside of the dust cover, and filter air inlets are provided on both sides of the dust cover.

[0013] As a further technical solution, the tower body adopts a multi-stage split connection structure, and the packing layer is located in the middle part of the tower body.

[0014] The beneficial effects of the embodiments disclosed herein are as follows: This disclosure addresses the core issue of high energy consumption in traditional absorption towers through a heat exchange circulating spray assembly. The circulating chamber of the heat exchange layer works in conjunction with the heat exchange box to recover waste heat from the exhaust gas within the tower to preheat the absorbent, eliminating the need for external heating and reducing energy consumption. The spiral heat exchange tubes increase the heat exchange area, improving preheating efficiency and allowing for more thorough contact between the absorbent and the exhaust gas, thus enhancing ammonia absorption. The inner ring pipe and spray nozzles ensure uniform spraying of the absorbent, while the packing layer increases the gas-liquid contact area, further improving recovery efficiency. The concentration detection head and switching control valve are linked, allowing unqualified absorbent to be recycled, avoiding waste and reducing replenishment frequency.

[0015] The entire component does not require a high-power pump to drive high-frequency circulation. Through the dual energy-saving design of waste heat recovery and recycling, it significantly reduces operating costs while improving ammonia recovery rate, meeting the needs of green and low-carbon production and solving the pain points of high energy consumption and low absorbent utilization rate of traditional equipment. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of this disclosure, the accompanying drawings used in the description of the embodiments of this disclosure will be briefly introduced below. Obviously, the drawings described below are merely some exemplary embodiments of this disclosure. For those skilled in the art, other drawings can be obtained based on the content of the exemplary embodiments of this disclosure and these drawings without any creative effort.

[0017] Figure 1 This is a schematic diagram of a structure in one embodiment of the present disclosure; Figure 2 This is an isometric drawing of the present disclosure; Figure 3 This is an isometric sectional view of the present disclosure; Figure 4 This is another isometric sectional view of this disclosure; In the diagram: 1. Tower body; 2. Bottom collection box; 3. Heat exchange circulation spray assembly; 3-1. Heat exchange box; 3-2. Heat exchange layer; 3-3. Circulation chamber; 3-4. Separation chamber; 3-5. Circulation pipe; 3-6. Packing layer; 3-7. Liquid inlet pipe; 3-8. Liquid outlet pipe; 3-9. Spiral heat exchange tube; 3-10. Inner ring pipe; 3-11. Spray nozzle; 3-12. Inlet pipe; 3-13. Water pump; 3-14. Switching control valve; 3-15. Concentration detection head; 4. Cooling assembly; 4-1. Heat conduction plate; 4-2. Heat exchange ring; 4-3. Heat dissipation fins; 4-4. Dust cover; 4-5. Cooling fan; 4-6. Filter inlet. Detailed Implementation

[0018] The present disclosure will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present disclosure and are not intended to limit the scope of the disclosure.

[0019] To keep the drawings concise, each drawing only schematically shows the parts relevant to the disclosure; these do not represent the actual structure of the product. Furthermore, for ease of understanding, in some drawings, only one of components with the same structure or function is schematically shown, or only one is labeled. In this document, "one" not only means "only one," but can also mean "more than one," and "several" includes "two" and "more than two."

[0020] In this document, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linkage" should be interpreted broadly. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to mechanical connections or electrical connections; they can refer to direct connections or indirect connections through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art can understand the specific meaning of the above terms in this disclosure based on the specific circumstances.

[0021] In this disclosure, unless otherwise expressly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0022] In the description of this embodiment, terms such as "upper," "lower," "left," and "right" are based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of description and simplification of operation, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this disclosure.

[0023] Furthermore, in the description of this application, the terms "first," "second," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0024] like Figures 1-4 As shown, it illustrates an energy-saving absorption tower for ammonia recovery from glycine tail gas according to an embodiment of this disclosure, comprising: The tower body 1 and the bottom collection box 2 are located at the bottom of the tower body 1; Cooling component 4 is disposed in the bottom collection box 2; Heat exchange circulation spray assembly 3 is disposed on the tower body 1; The heat exchange circulating spray assembly 3 includes a heat exchange box 3-1, which is located on the outside of the tower body 1. A heat exchange layer 3-2 is arranged around the inner wall of the tower body 1. Several circulation chambers 3-3 are formed around the heat exchange layer 3-2, and a pair of partition chambers 3-4 are formed within the heat exchange layer 3-2, separating the circulation chambers 3-3. A circulation pipe 3-5 connects the outer wall of the tower body 1 to the heat exchange box 3-1. A packing layer 3-6 is arranged at the upper end of the tower body 1. One of the circulation pipes 3-5 is connected to the heat exchange box 3-1 via a water pump 3-13. The pair of circulation pipes 3-5 are located at the top and bottom of the heat exchange box 3-1, respectively. An inlet pipe 3-7 is located at the bottom of the heat exchange box 3-1, and an outlet pipe 3-8 is located at the top of the heat exchange box 3-1. The tower body 1 is equipped with a spiral heat exchange tube 3-9, with its two ends connected to the inlet pipe 3-7 and the outlet pipe 3-8, respectively. An inner ring pipe 3-10 is arranged around the top of the tower body 1, and several spray nozzles 3-11 are arranged around the inner ring pipe 3-10. One end of the outlet pipe 3-8 is connected to an inlet pipe 3-12, the upper end of which is connected to the inner ring pipe 3-10. A water pump 3-13 is installed on the outside of the bottom collection tank 2, with its output end connected to the lower end of the inlet pipe 3-12. Switching control valves 3-14 are installed at both the outlet pipe 3-8 and the output end of the water pump 3-13. A concentration detection head 3-15 is installed on the bottom surface of the bottom collection tank 2. The water pump 3-13 can reuse dilute acid solutions with insufficient concentration.

[0025] In some examples, in order to achieve preheating and recycling of dilute acid, improve ammonia absorption efficiency and reduce energy consumption, and solve the problems of high energy consumption and low utilization rate of dilute acid in traditional absorption towers, a heat exchange circulation spray assembly 3 was designed. This assembly includes a tower body 1 made of corrosion-resistant carbon steel welded together. The heat exchange layer 3-2 around the inner wall is tightly attached to the wall of the tower body 1. Several circulation chambers 3-3 in the heat exchange layer 3-2 are arranged in an array. A pair of partition chambers 3-4 divide the circulation chambers 3-3 into independent inlet and outlet channels to ensure that the heat exchange medium flows in an orderly manner in the chamber and fully exchanges heat with the high-temperature exhaust gas inside the tower body 1.

[0026] The heat exchange box 3-1 on the outside of the tower body 1 is fixed by a bracket and connected to the tower body 1 by two circulation pipes 3-5. The two circulation pipes 3-5 are located at the top and bottom of the heat exchange box 3-1, respectively. One of the circulation pipes 3-5 is connected to the heat exchange box 3-1 through a water pump 3-13, forming a closed heat exchange loop. The spiral heat exchange tube 3-9 inside the heat exchange box 3-1 is made of a high thermal conductivity metal material. Its two ends are connected to the inlet pipe 3-7 and the outlet pipe 3-8, respectively. The dilute acid solution enters the spiral heat exchange tube 3-9 through the inlet pipe 3-7 and exchanges heat with the heat medium in the circulation loop to achieve preheating. The preheated dilute acid solution is then transported to the inlet pipe 3-12 through the outlet pipe 3-8.

[0027] The packing layer 3-6 at the upper end of the tower body 1 is made of high-efficiency mass transfer packing, which can increase the gas-liquid contact area. The inner ring pipe 3-10 at the top of the tower body 1 is fixed by a bracket. The spray nozzles 3-11 are evenly distributed around the pipe. The upper end of the inlet pipe 3-12 is connected to the inner ring pipe 3-10, and the lower end is connected to the output end of the water pump 3-13 outside the bottom collection box 2. The preheated dilute acid liquid is atomized by the spray nozzles 3-11 and evenly sprayed on the surface of the packing layer 3-6, which fully contacts the rising glycine tail gas to achieve efficient ammonia absorption.

[0028] Both the outlet pipe 3-8 and the output end of the water pump 3-13 are equipped with switching control valves 3-14. The concentration detection head 3-15 in the bottom collection tank 2 can monitor the concentration of the absorbent in real time. When the concentration does not meet the standard, the switching control valve 3-14 opens the circulation loop, and the water pump 3-13 delivers the dilute acid solution to the inner loop pipe 3-10 for spray absorption. After the concentration meets the standard, it switches to the discharge loop. This structure realizes the recycling of dilute acid solution and waste heat recovery, which greatly improves the ammonia absorption efficiency and energy saving of the device.

[0029] like Figures 1-4 As shown in the figure, the cooling component 4 in this embodiment includes a heat-conducting plate 4-1, which is disposed inside the side wall of the bottom collection box 2. Several heat exchange rings 4-2 are connected in the heat-conducting plate 4-1. The heat exchange rings 4-2 are evenly distributed around the inside of the bottom collection box 2. Heat dissipation fins 4-3 are provided at the outer end of the heat-conducting plate 4-1. A dust cover 4-4 is provided outside the bottom collection box 2. Several cooling fans 4-5 are installed on the outside of the dust cover 4-4. Filter air inlets 4-6 are provided on both sides of the dust cover 4-4.

[0030] In some examples, in order to achieve rapid cooling of the ammonia liquid after absorption and to solve the problems of low efficiency and susceptibility to dust in traditional cooling methods, a cooling component 4 was designed. This component includes a bottom collection box 2 made of stainless steel, which is used to collect the liquid after ammonia absorption. The heat-conducting plate 4-1 inside the side wall of the box is made of a metal plate with a high thermal conductivity and is tightly attached to the box wall to ensure that the heat of the liquid inside the box is efficiently transferred to the heat-conducting plate 4-1.

[0031] Several heat exchange rings 4-2 connected to the heat-conducting plate 4-1 are evenly distributed around the bottom collection box 2. The annular structure of the heat exchange rings 4-2 increases the contact area with the liquid, which can quickly transfer heat from the liquid to the heat-conducting plate 4-1, preventing local overheating of the liquid from affecting the stable storage of ammonia. The heat dissipation fins 4-3 at the outer end of the heat-conducting plate 4-1 are welded and fixed to the heat-conducting plate 4-1. The fins adopt an array structure design, which greatly increases the contact area with the air and enhances the heat dissipation effect.

[0032] The dust cover 4-4 on the outside of the bottom collection box 2 is fixed with bolts. The cover completely covers the heat dissipation fins 4-3. The filter air inlets 4-6 on both sides of the dust cover 4-4 have built-in filters that can filter dust and impurities in the air and prevent dust from adhering to the surface of the fins and affecting heat dissipation.

[0033] Several cooling fans 4-5 installed on the outside of the dust cover 4-4 blow air toward the heat dissipation fins 4-3, forming a forced air cooling system, accelerating the airflow around the heat dissipation fins 4-3, and quickly dissipating heat to the outside environment.

[0034] This structure achieves rapid and uniform cooling of the absorbent liquid through efficient heat conduction via heat exchange ring 4-2, heat conduction plate 4-1, and heat dissipation fins 4-3, combined with forced air cooling by cooling fan 4-5. The design of dust cover 4-4 and filter inlet 4-6 effectively blocks dust, ensuring the long-term stable operation of the heat dissipation system and providing a reliable guarantee for the efficient recovery and storage of ammonia.

[0035] For example, such as Figure 3 As shown, the tower body 1 adopts a multi-stage split connection structure, and the packing layer 3-6 is located in the middle layer of the tower body 1.

[0036] In some examples, tower body 1 adopts a multi-stage split connection structure, with each section of tower body 1 securely connected by flanges and gaskets, facilitating easy assembly and disassembly while ensuring excellent sealing. This split design facilitates the inspection, replacement, and maintenance of core components such as the heat exchange layer 3-2 and packing layer 3-6 inside tower body 1 without requiring complete disassembly of tower body 1, significantly reducing operation and maintenance difficulty and costs. The middle section of tower body 1 provides ample installation space for packing layer 3-6, ensuring that the arrangement height and area of ​​packing layer 3-6 are adapted to gas-liquid mass transfer requirements, thereby improving ammonia absorption efficiency.

[0037] In practical use: The tower body 1 is assembled and fixed using a multi-stage modular structure. The bottom collection box 2 is connected to the bottom of the tower body 1. The heat exchange box 3-1 is installed on the outside of the tower body 1. The circulation pipe 3-5 connects the tower body 1 and the heat exchange box 3-1 to form a closed loop. The inlet pipe 3-12 connects the outlet pipe 3-8 and the inner ring pipe 3-10. The water pump 3-13 is started, and the absorbent is sent through the inlet pipe 3-7 into the spiral heat exchange tube 3-9 of the heat exchange box 3-1. It preheats by exchanging heat with the heat medium in the circulation chamber 3-3 of the heat exchange layer 3-2 of the tower body 1. The preheated absorbent enters the inner ring pipe 3-10 through the outlet pipe 3-8 and the inlet pipe 3-12, and is atomized and sprayed onto the packing layer 3-1 through the spray nozzle 3-11. 6. Glycine tail gas is introduced into tower 1 and comes into countercurrent contact with the absorbent on the surface of packing layer 3-6, where ammonia is efficiently absorbed. The absorbed liquid is collected in the bottom collection tank 2. Concentration detection head 3-15 monitors the liquid concentration. If the concentration does not meet the standard, circulation is started by switching control valve 3-14. Water pump 3-13 transports the liquid back to the inner ring pipeline 3-10 for reuse. After meeting the standard, the liquid is discharged. At the same time, cooling component 4 is started. Cooling fan 4-5 draws in air through filter inlet 4-6 and blows it onto heat dissipation fins 4-3. Heat is transferred to the fins through heat conduction plate 4-1 and heat exchange ring 4-2 for rapid dissipation, thereby cooling the liquid and ensuring absorption efficiency. Continuous operation can complete continuous ammonia recovery.

[0038] It should be noted that the above embodiments are only used to illustrate the technical solutions of this disclosure and are not intended to limit it. Although this disclosure has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of this disclosure without departing from the spirit and scope of the technical solutions of this disclosure, and all such modifications and substitutions should be covered within the scope of the claims of this disclosure.

Claims

1. An energy-saving absorption tower for ammonia recovery from glycine tail gas, characterized in that, include: The tower body (1) and the bottom collection box (2) are arranged at the bottom of the tower body (1); Cooling component (4), the cooling component (4) is disposed in the bottom collection box (2); A heat exchange circulating spray assembly (3) is disposed on the tower body (1); The heat exchange circulating spray assembly (3) includes a heat exchange box (3-1), which is located on the outside of the tower body (1). A heat exchange layer (3-2) is provided around the inner wall of the tower body (1). Several circulation chambers (3-3) are opened around the inner wall of the heat exchange layer (3-2). A pair of partition chambers (3-4) are opened in the heat exchange layer (3-2). The circulation chambers (3-3) are separated by the partition chambers (3-4). A circulation pipe (3-5) is connected between the outer wall of the tower body (1) and the heat exchange box (3-1). A packing layer (3-6) is provided at the upper end of the inner wall of the tower body (1).

2. The energy-saving absorption tower for ammonia recovery from glycine tail gas according to claim 1, characterized in that, One of the circulation pipes (3-5) is connected to the heat exchange box (3-1) via a water pump (3-13). A pair of circulation pipes (3-5) are located at the top and bottom of the heat exchange box (3-1) respectively. The bottom of the heat exchange box (3-1) is provided with an inlet pipe (3-7), and the top of the heat exchange box (3-1) is provided with an outlet pipe (3-8).

3. The energy-saving absorption tower for ammonia recovery from glycine tail gas according to claim 2, characterized in that, The heat exchange box (3-1) is equipped with a spiral heat exchange tube (3-9), and the two ends of the spiral heat exchange tube (3-9) are connected to the liquid inlet pipe (3-7) and the liquid outlet pipe (3-8) respectively. An inner ring pipe (3-10) is provided around the top of the tower body (1).

4. The energy-saving absorption tower for ammonia recovery from glycine tail gas according to claim 3, characterized in that, A number of spray nozzles (3-11) are arranged around the inner ring pipe (3-10). One end of the liquid outlet pipe (3-8) is connected to the inlet pipe (3-12). The upper end of the inlet pipe (3-12) is connected to the inner ring pipe (3-10). A water pump (3-13) is arranged on the outside of the bottom collection box (2). The output end of the water pump (3-13) is connected to the lower end of the inlet pipe (3-12).

5. The energy-saving absorption tower for ammonia recovery from glycine tail gas according to claim 4, characterized in that, A switching control valve (3-14) is provided at one end of the liquid outlet pipe (3-8) and at the output end of the water pump (3-13). A concentration detection head (3-15) is provided on the bottom surface of the bottom collection box (2). The water pump (3-13) can reuse dilute acid solution whose concentration does not meet the standard.

6. The energy-saving absorption tower for ammonia recovery from glycine tail gas according to claim 1, characterized in that, The cooling component (4) includes a heat-conducting plate (4-1), which is disposed inside the side wall of the bottom collection box (2). Several heat exchange rings (4-2) are connected in the heat-conducting plate (4-1), and the heat exchange rings (4-2) are evenly distributed around the inside of the bottom collection box (2).

7. The energy-saving absorption tower for ammonia recovery from glycine tail gas according to claim 6, characterized in that, The heat-conducting plate (4-1) is provided with heat dissipation fins (4-3) at its outer end. The bottom collection box (2) is provided with a dust cover (4-4) on its outside. Several cooling fans (4-5) are installed on the outside of the dust cover (4-4). Filter air inlets (4-6) are opened on both sides of the dust cover (4-4).

8. The energy-saving absorption tower for ammonia recovery from glycine tail gas according to claim 1, characterized in that, The tower body (1) adopts a multi-stage split connection structure, and the packing layer (3-6) is located in the middle layer of the tower body (1).

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