A refined sulfuric acid absorption tower and an absorption method thereof

Abstract

The present application provides a kind of refined sulfuric acid absorption tower and its absorption method, including tower body, pre-absorption component and final absorption component are arranged in tower body, and the bottom of both is connected by communicating pipe, the bottom of pre-absorption component is connected with inlet pipe, the top of pre-absorption component is provided with shower head, the bottom of final absorption component is connected with outlet pipe, pre-absorption component and final absorption component are internally provided with packing;The top of pre-absorption component and final absorption component is connected on the closed space formed by multiple plates, and the closed space forms two chambers, pre-absorption component is connected in first chamber, and final absorption component is connected in second chamber, first chamber is connected with communicating pipe, second chamber is communicated with inlet pipe, and second chamber is also connected with outlet pipe.The present application provides a kind of refined sulfuric acid absorption tower and its absorption method, improves and simplifies the equipment inside existing refined sulfuric acid tower, and makes that gas-liquid distribution is uniform, improves absorption efficiency.

Description

Technical Field

[0001] This invention belongs to the field of sulfuric acid processing technology, specifically relating to a refined sulfuric acid absorption tower and its absorption method. Background Technology

[0002] Sulfuric acid is a highly reactive diprotic inorganic strong acid that reacts with most metals. High-concentration sulfuric acid has strong hygroscopic properties and can be used as a dehydrating agent. It also releases a large amount of heat when carbonized with water, reacting with carbohydrate-containing materials such as wood, paper, cotton and linen fabrics, and biological hides. In the current field of sulfuric acid production, absorption towers are the equipment used to achieve the absorption process; they are required as an auxiliary processing method in the refining of sulfuric acid.

[0003] Chinese invention patent application number CN202411465400X discloses an absorption tower for refining sulfuric acid processing, which can effectively achieve full contact between gas and sulfuric acid and increase the contact area between liquid and gas. However, the absorption tower still has the following technical problems: the device is relatively complex due to the installation of a wire mesh demister and stirring blades; the parts are easily damaged when exposed to acidic environment for a long time and are inconvenient to replace; in addition, the existing absorption tower lacks precise control over the temperature and concentration of circulating sulfuric acid, resulting in large fluctuations in absorption conditions and unstable product quality. Summary of the Invention

[0004] The purpose of this invention is to provide a refined sulfuric acid absorption tower and its absorption method, which solves the technical problem of how to improve and simplify the internal equipment of the existing refined sulfuric acid tower, and make the gas-liquid distribution uniform and improve the absorption efficiency. At the same time, it can also accurately control the temperature and concentration of circulating concentrated sulfuric acid in the existing absorption tower, avoiding the problems of large fluctuations in absorption conditions and unstable product quality, and has important industrial application value.

[0005] A refined sulfuric acid absorption tower includes a tower body, in which a pre-absorption component and a final absorption component are disposed, the bottom ends of which are connected by a connecting pipe. The bottom end of the pre-absorption component is connected to an air inlet pipe, the top end of the pre-absorption component is provided with a spray head, and the bottom end of the final absorption component is connected to a liquid outlet pipe. The pre-absorption component and the final absorption component are filled with packing material.

[0006] The top ends of the pre-absorption assembly and the final absorption assembly are connected to a closed space formed by multiple plates. The closed space forms two chambers. The pre-absorption assembly is connected to the first chamber, and the final absorption assembly is connected to the second chamber. The first chamber is connected to the connecting pipe, and the second chamber is connected to the air inlet pipe and the second chamber is also connected to the air outlet pipe.

[0007] The pre-absorption assembly includes multiple pre-absorption tubes arranged in parallel to each other, a buffer box connected to the top of the multiple pre-absorption tubes, the multiple pre-absorption tubes vertically passing through a fixed base plate, the fixed base plate being positioned and connected inside the tower body, the bottom ends of the multiple pre-absorption tubes being closed and fixed to the inner bottom end of the tower body, and the interior of the multiple pre-absorption tubes being filled with packing material.

[0008] The final absorption assembly includes multiple parallel final absorption tubes, a connecting box connected to the top of the multiple final absorption tubes, multiple final absorption tubes vertically passing through a fixed base plate, and the bottom ends of the multiple final absorption tubes being closed and fixed to the inner bottom of the tower body. The interior of the multiple final absorption tubes is filled with packing material; the gas outlet pipe is connected to and passes through the bottom end of the pre-absorption tube.

[0009] The enclosed space includes a fixed base plate and a fixed top plate that are parallel to each other, and an intermediate plate that is vertically fixed between the fixed base plate and the fixed top plate, dividing it into two chambers: a first chamber and a second chamber. A buffer box is provided in the first chamber, and a connecting box is provided in the second chamber.

[0010] The connecting pipe is equipped with a first valve and a second valve. The first chamber is connected to the connecting pipe through an internal circulation pipe, which is located between the first valve and the second valve.

[0011] The air intake pipe is connected and installed at the bottom end of the plurality of pre-absorption pipes.

[0012] The second chamber is connected to the air intake pipe via an external circulation pipe.

[0013] It also includes a monitoring system and a heat exchanger; the monitoring system includes a thermometer, a concentration meter, a level gauge and a pressure gauge. When the acid concentration is lower than the preset value, it automatically replenishes demineralized water. When the temperature deviates from the set range, it automatically adjusts the cooling amount of the circulating acid to maintain the concentration of refined concentrated sulfuric acid in the tower at 98%-98.5% and the temperature at 50℃-70℃.

[0014] A method for absorbing refined sulfuric acid, employing a refined sulfuric acid absorption tower, specifically includes the following steps:

[0015] Step S1: A pre-absorption assembly and a final absorption assembly are installed in the tower body, which are used for the preliminary absorption and final absorption of SO3 gas, respectively. The pre-absorption assembly and the final absorption assembly extend from the bottom end of the tower body to its top end.

[0016] Step S2: Connect one end of the air inlet pipe to the pre-absorption component and introduce SO3 gas into the pre-absorption component. At the same time, the spray head at the top of the pre-absorption component is activated to spray H2SO3 liquid with a concentration of P into the pre-absorption component.

[0017] Step S3: The top of the pre-absorption component is connected to a closed first chamber. The first chamber is connected to a connecting pipe through an internal circulation pipe. The two ends of the connecting pipe are connected to the two ends of the pre-absorption component and the final absorption component, respectively. The SO3 gas that is not completely absorbed enters the final absorption component. A balance pipe connected to the outside atmosphere is installed on the first chamber.

[0018] Step S4: At the same time, concentrated sulfuric acid in the pre-absorption component enters the final absorption component, where further SO3 gas absorption is achieved.

[0019] Step S5: The unabsorbed SO3 gas enters the external circulation pipe from the final absorption component and then enters the intake pipe, repeating the above process.

[0020] Step S6: When the concentration of concentrated sulfuric acid in the final absorption component reaches the standard, the concentrated sulfuric acid is discharged through the outlet pipe. At this time, the final absorption component and the pre-absorption component form a communicating vessel. The concentrated sulfuric acid in the pre-absorption component re-enters the final absorption component, and the spray head continues to spray. The above process is repeated.

[0021] Step S7: When the gas concentration in the second chamber connected to the top of the final absorption component reaches the emission standard, open the exhaust pipe to exhaust the gas.

[0022] Technical features not described in detail in this solution are based on the conventional understanding and operation of those skilled in the art, and can be implemented in real time; therefore, they will not be elaborated further. The power equipment and electronic equipment in this solution are all connected to a controller, such as a PLC controller, for unified adjustment and control.

[0023] This invention achieves the following significant effects:

[0024] (1) Existing sulfuric acid absorption towers have problems such as uneven spraying of raw sulfuric acid and uneven gas-liquid contact, resulting in low sulfur trioxide absorption efficiency. In particular, the uneven distribution of sulfur trioxide gas in the tower can easily lead to local over-concentration or over-dilute phenomena, which directly affects the production efficiency of concentrated sulfuric acid. This solution is designed to address this technical problem. The innovation of this solution is that it sets up a pre-absorption component and a final absorption component, which allows the sulfur trioxide absorption process to continue for a long time, from the bottom to the top of the tower. At the same time, the final absorption component is set up to achieve secondary absorption, which increases the absorption efficiency. The reaction process is confined to the pipeline, which reduces the cross-sectional area of ​​the reaction. The smaller cross-sectional area ensures the uniform distribution of sulfur trioxide gas in the tower.

[0025] (2) Specifically, this solution includes a pre-absorption component and a final absorption component, which work together to achieve the following technical effects:

[0026] First, the pre-absorption tube and the final absorption tube are placed vertically, and the sulfur trioxide gas flows from bottom to top, which increases the contact time with concentrated sulfuric acid and the residence time of the gas in concentrated sulfuric acid, thus helping to increase the reaction efficiency.

[0027] Secondly, the cross-sectional area of ​​the pre-absorption tube and the final absorption tube is artificially reduced, which makes the distribution of concentrated sulfuric acid in the tube more uniform and avoids the high cost of adding stirring equipment in the existing technology.

[0028] Third, the absorption process can be repeated cyclically through the final absorption component;

[0029] (3) It is equipped with a first chamber and a second chamber, which achieves the following technical effects:

[0030] Firstly, the first chamber facilitates internal circulation. The first chamber is connected to the connecting pipe through the internal circulation pipe, which helps to allow the gas that has not been fully absorbed to enter the final absorption pipe or to be discharged directly.

[0031] Secondly, the second chamber facilitates external circulation. The second chamber is connected to the intake pipe through an external circulation pipe, which allows unabsorbed gas to re-enter the pre-absorption pipe or be discharged directly.

[0032] (4) The present invention is equipped with a sulfuric acid circulation mechanism and a monitoring system, which realizes the recycling of concentrated sulfuric acid and precise control of absorption conditions, improves the utilization rate of raw materials, reduces energy consumption, and ensures the stability of product quality; at the same time, a heat exchanger is also set up, which is connected to the pre-absorption tube and the final absorption tube, which helps to achieve temperature regulation. Attached Figure Description

[0033] Figure 1 This is a front view of the absorption tower in this invention.

[0034] Figure 2 This is a schematic diagram of the absorption tower in this invention.

[0035] Figure 3 This is a front view of the internal structure of the absorption tower in this invention.

[0036] Figure 4 This is a schematic diagram of the internal structure of the absorption tower in this invention.

[0037] The attached diagram is labeled as follows: 1. Base; 2. Inlet pipe; 3. Support plate; 4. Fence; 5. Outlet pipe; 6. External circulation pipe; 7. Tower body; 8. Liquid outlet pipe; 9. Pre-absorption pipe; 10. Fixed base plate; 11. Buffer tank; 12. Spray head; 13. Fixed top plate; 15. Intermediate plate; 16. Connecting box; 17. Final absorption pipe; 18. Internal circulation pipe; 19. First valve; 20. Second valve; 21. Connecting pipe. Detailed Implementation

[0038] To more clearly illustrate the technical features of this solution, the following detailed implementation method will be used to explain the solution.

[0039] Example 1

[0040] See Figures 1-4 A refined sulfuric acid absorption tower includes a tower body 7, in which a pre-absorption component and a final absorption component are provided. The bottom ends of the two components are connected by a connecting pipe 21. The bottom end of the pre-absorption component is connected to an air inlet pipe 2, and the top end of the pre-absorption component is provided with a spray head 12. The bottom end of the final absorption component is connected to a liquid outlet pipe 8. The pre-absorption component and the final absorption component are filled with packing material.

[0041] The tops of the pre-absorption assembly and the final absorption assembly are connected to a closed space formed by multiple plates. The closed space forms two chambers. The pre-absorption assembly is connected to the first chamber, and the final absorption assembly is connected to the second chamber. The first chamber is connected to the connecting pipe 21, and the second chamber is connected to the inlet pipe 2. The second chamber is also connected to the outlet pipe 5.

[0042] More preferably, a base 1 is fixed at the bottom of the tower body 7; a support plate 3 is fixed at the top of the tower body 7, and a railing 4 is fixed on the support plate 3.

[0043] The pre-absorption assembly includes multiple pre-absorption tubes 9 arranged in parallel to each other, a buffer box 11 connected to the top of the multiple pre-absorption tubes 9, the multiple pre-absorption tubes 9 vertically passing through a fixed base plate 10, the fixed base plate 10 being positioned and connected inside the tower body 7, the bottom ends of the multiple pre-absorption tubes 9 being closed and fixed to the inner bottom end of the tower body 7, and the interior of the multiple pre-absorption tubes 9 being filled with packing material.

[0044] The final absorption assembly includes multiple parallel final absorption tubes 17, a connecting box 16 connected to the top of the multiple final absorption tubes 17, the multiple final absorption tubes 17 vertically passing through the fixed base plate 10, the bottom ends of the multiple final absorption tubes 17 being closed and fixed to the inner bottom of the tower body 7, and the interior of the multiple final absorption tubes 17 being filled with packing material; the gas outlet pipe 5 is connected to the bottom end of the pre-absorption tube 9.

[0045] The enclosed space includes a fixed base plate 10 and a fixed top plate 13 that are parallel to each other, and an intermediate plate 15 that is vertically fixed between the fixed base plate 10 and the fixed top plate 13, which divides the space into two chambers: a first chamber and a second chamber. A buffer box 11 is installed in the first chamber, and a connecting box 16 is installed in the second chamber.

[0046] A first valve 19 and a second valve 20 are provided on the connecting pipe 21. The first chamber is connected to the connecting pipe 21 through an internal circulation pipe 18, which is located between the first valve 19 and the second valve 20.

[0047] In addition to the first valve 19 and the second valve 20, each pipeline in the device of this scheme is equipped with a solenoid valve. The solenoid valve is connected to the controller to achieve full on / off control. For the sake of simplicity, it will not be shown in the attached figure.

[0048] The intake pipe 2 is connected to the bottom of multiple pre-absorption pipes 9.

[0049] The second chamber is connected to the air intake pipe 2 via the external circulation pipe 6.

[0050] It also includes a monitoring system and a heat exchanger. The monitoring system includes a thermometer, concentration meter, level gauge, pressure gauge, and controller. When the acid concentration is lower than the preset value, it automatically replenishes demineralized water. When the temperature deviates from the set range, it automatically adjusts the cooling rate of the circulating acid to maintain the concentration of refined sulfuric acid in the tower at 98%-98.5% and the temperature at 50℃-70℃. Both the monitoring system and the heat exchanger are existing technologies. The heat exchange tubes in the heat exchanger are arranged outside the inner circulation pipe 18 for temperature control and regulation. The specific temperature control is uniformly implemented through the controller, which is easily operated and implemented by those skilled in the art and will not be described in detail here.

[0051] The specific working process of this invention is as follows:

[0052] Existing concentrated sulfuric acid absorption towers suffer from uneven spraying of the raw material concentrated sulfuric acid and uneven gas-liquid contact, resulting in low sulfur trioxide absorption efficiency. In particular, the uneven distribution of sulfur trioxide gas within the tower can easily lead to localized over-concentration or under-concentration, directly affecting the production efficiency of concentrated sulfuric acid. This solution addresses this technical problem. The innovation of this solution lies in the inclusion of pre-absorption and final absorption components, allowing the sulfur trioxide absorption process to continue for a long time, from the bottom to the top of the tower. Simultaneously, the final absorption component enables secondary absorption, increasing absorption efficiency. The reaction process is confined to the pipeline, reducing the cross-sectional area of ​​the reaction and ensuring uniform distribution of sulfur trioxide gas within the tower with a smaller cross-sectional area.

[0053] Specifically, this scheme sets up a pre-absorption component and a final absorption component, which work together. The pre-absorption tube 9 and the final absorption tube 17 are placed vertically, and the sulfur trioxide gas flows from bottom to top, which increases the contact time with concentrated sulfuric acid and the residence time of the gas in concentrated sulfuric acid, thus helping to increase the reaction efficiency.

[0054] The pre-absorption tube 9 and the final absorption tube 17 have their cross-sectional areas artificially reduced, making the distribution of concentrated sulfuric acid in the tubes more uniform and avoiding the high cost of adding stirring equipment in the prior art; the final absorption component allows the absorption process to be repeated cyclically.

[0055] The system is equipped with a first chamber and a second chamber. The first chamber facilitates internal circulation and is connected to the connecting pipe 21 via the internal circulation pipe 18, which helps to allow unabsorbed gas to enter the final absorption pipe 17 or to be discharged directly. The second chamber facilitates external circulation and is connected to the air inlet pipe 2 via the external circulation pipe 6, which allows unabsorbed gas to re-enter the pre-absorption pipe 9 or to be discharged directly.

[0056] This invention is equipped with a concentrated sulfuric acid circulation mechanism and a monitoring system, which realizes the recycling of concentrated sulfuric acid and precise control of absorption conditions, improves raw material utilization, reduces energy consumption, and ensures stable product quality. At the same time, a heat exchanger is also set up, which is connected to the pre-absorption tube 9 and the final absorption tube 17, which helps to achieve temperature regulation.

[0057] Example 2

[0058] A method for absorbing refined sulfuric acid, employing a refined sulfuric acid absorption tower, specifically includes the following steps:

[0059] Step S1: A pre-absorption component and a final absorption component are provided in the tower body 7, which are used for the preliminary absorption and final absorption of SO3 gas, respectively. The pre-absorption component and the final absorption component extend from the bottom end to the top end of the tower body 7, respectively.

[0060] Step S2: Connect one end of the air inlet pipe 2 to the pre-absorption component and introduce SO3 gas into the pre-absorption component. At the same time, the spray head 12 at the top of the pre-absorption component is activated to spray H2SO3 liquid with a concentration of P into the pre-absorption component.

[0061] Step S3: The top of the pre-absorption component is connected to the closed first chamber. The first chamber is connected to the connecting pipe 21 through the internal circulation pipe 18. The two ends of the connecting pipe 21 are connected to the two ends of the pre-absorption component and the final absorption component, respectively. The SO3 gas that is not completely absorbed enters the final absorption component. A balance pipe connected to the outside atmosphere is set on the first chamber to balance the internal and external air pressure and to discharge excess gas that meets the standards. For the sake of simplifying the design, the balance pipe is not marked.

[0062] Step S4: At the same time, concentrated sulfuric acid in the pre-absorption component enters the final absorption component, where further SO3 gas absorption is achieved.

[0063] Step S5: The unabsorbed SO3 gas enters the external circulation pipe 6 from the final absorption component and then enters the intake pipe 2, repeating the above process.

[0064] Step S6: When the concentration of concentrated sulfuric acid in the final absorption component reaches the standard, the concentrated sulfuric acid is discharged through the outlet pipe 8. At this time, the final absorption component and the pre-absorption component form a communicating vessel. The concentrated sulfuric acid in the pre-absorption component re-enters the final absorption component, and the spray head 12 continues to spray. The above process is repeated.

[0065] Step S7: When the gas concentration in the second chamber connected to the top of the final absorption component reaches the emission standard, open the exhaust pipe 5 to exhaust the gas.

[0066] The technical features of this invention not described can be implemented by or using existing technology, and will not be repeated here. Of course, the above description is not a limitation of this invention, and this invention is not limited to the examples above. Any changes, modifications, additions or substitutions made by those skilled in the art within the scope of this invention should also be within the protection scope of this invention.

Claims

1. A refined sulfuric acid absorption tower, comprising a tower body (7), characterized in that, The tower body (7) is provided with a pre-absorption component and a final absorption component. The bottom ends of the two are connected by a connecting pipe (21). The bottom end of the pre-absorption component is connected to the air inlet pipe (2). The top end of the pre-absorption component is provided with a spray head (12). The bottom end of the final absorption component is connected to the liquid outlet pipe (8). The pre-absorption component and the final absorption component are provided with packing material. The top ends of the pre-absorption component and the final absorption component are connected to a closed space formed by multiple plates. The closed space forms two chambers. The pre-absorption component is connected to the first chamber, and the final absorption component is connected to the second chamber. The first chamber is connected to the connecting pipe (21), and the second chamber is connected to the air inlet pipe (2). The second chamber is also connected to the air outlet pipe (5).

2. The purified sulfuric acid absorption tower according to claim 1, characterized in that, The pre-absorption assembly includes multiple pre-absorption tubes (9) arranged in parallel with each other, and a buffer box (11) connected to the top of the multiple pre-absorption tubes (9). The multiple pre-absorption tubes (9) pass vertically through a fixed base plate (10). The fixed base plate (10) is positioned and connected inside the tower body (7). The bottom ends of the multiple pre-absorption tubes (9) are closed and fixed to the inner bottom end of the tower body (7). The interior of the multiple pre-absorption tubes (9) is filled with packing material.

3. The purified sulfuric acid absorption tower according to claim 1, characterized in that, The final absorption assembly includes multiple parallel final absorption tubes (17), a connecting box (16) connected to the top of the multiple final absorption tubes (17), the multiple final absorption tubes (17) vertically passing through the fixed base plate (10), the bottom ends of the multiple final absorption tubes (17) being closed and fixed to the inner bottom end of the tower body (7), and the interior of the multiple final absorption tubes (17) being filled with packing material; the gas outlet pipe (5) is connected to the bottom end of the pre-absorption tube (9).

4. The purified sulfuric acid absorption tower according to claim 1, characterized in that, The enclosed space includes a fixed base plate (10) and a fixed top plate (13) that are parallel to each other, and an intermediate plate (15) that is vertically fixed between the fixed base plate (10) and the fixed top plate (13), which divides the space into two chambers: the first chamber and the second chamber. A buffer box (11) is provided in the first chamber, and a connecting box (16) is provided in the second chamber.

5. A refined sulfuric acid absorption tower according to claim 1, characterized in that, The connecting pipe (21) is provided with a first valve (19) and a second valve (20). The first chamber is connected to the connecting pipe (21) through an internal circulation pipe (18). The internal circulation pipe (18) is located between the first valve (19) and the second valve (20).

6. A refined sulfuric acid absorption tower according to claim 1, characterized in that, The air inlet pipe (2) is connected to the bottom end of the plurality of pre-absorption pipes (9).

7. A refined sulfuric acid absorption tower according to claim 1, characterized in that, The second chamber is connected to the air inlet pipe (2) via an external circulation pipe (6).

8. A refined sulfuric acid absorption tower according to claim 1, characterized in that, It also includes a monitoring system and a heat exchanger; the monitoring system includes a thermometer, a concentration meter, a level gauge and a pressure gauge. When the acid concentration is lower than the preset value, it automatically replenishes demineralized water. When the temperature deviates from the set range, it automatically adjusts the cooling amount of the circulating acid to maintain the concentration of refined concentrated sulfuric acid in the tower at 98%-98.5% and the temperature at 50℃-70℃.

9. A method for absorbing refined sulfuric acid, using a refined sulfuric acid absorption tower as described in any one of claims 1-8, characterized in that, Specifically, the steps include the following: Step S1: A pre-absorption component and a final absorption component are provided in the tower body (7) for the preliminary absorption and final absorption of SO3 gas, respectively. The pre-absorption component and the final absorption component extend from the bottom end of the tower body (7) to its top end. Step S2: Connect one end of the inlet pipe (2) to the pre-absorption component and introduce SO3 gas into the pre-absorption component. At the same time, the spray head (12) at the top of the pre-absorption component works to spray H2SO4 liquid with a concentration of P into the pre-absorption component. Step S3: The top of the pre-absorption component is connected to the closed first chamber. The first chamber is connected to the connecting pipe (21) through the internal circulation pipe (18). The two ends of the connecting pipe (21) are connected to the two ends of the pre-absorption component and the final absorption component, respectively. The SO3 gas that is not completely absorbed enters the final absorption component. Step S4: At the same time, concentrated sulfuric acid in the pre-absorption component enters the final absorption component, where further SO3 gas absorption is achieved. Step S5: The unabsorbed SO3 gas enters the external circulation pipe (6) from the final absorption component and then enters the intake pipe (2), repeating the above process; Step S6: When the concentration of concentrated sulfuric acid in the final absorption component reaches the standard, the concentrated sulfuric acid is discharged through the outlet pipe (8). At this time, the final absorption component and the pre-absorption component form a communication device. The concentrated sulfuric acid in the pre-absorption component re-enters the final absorption component, and the spray head (12) continues to spray. The above process is repeated. Step S7: When the gas concentration in the second chamber connected to the top of the final absorption component reaches the emission standard, open the exhaust pipe (5) to exhaust the gas.

Images