Differential pressure measuring mechanism for desulfurizing tower and desulfurizing tower

Abstract

The differential pressure measuring mechanism comprises a negative pressure taking pipe, a positive pressure taking pipe, an upper arc pipe, a lower arc pipe, a plurality of pressure taking valves and a differential pressure transmitter, and the negative pressure taking pipe and the positive pressure taking pipe are vertically arranged; one end of the upper arc pipe is communicated with the top end of the negative pressure taking pipe, the other end of the upper arc pipe is communicated with a plurality of negative pressure side pressure taking ports in the upper part of the desulfurizing tower, one end of the lower arc pipe is communicated with the top end of the positive pressure taking pipe, and the other end of the lower arc pipe is communicated with a plurality of positive pressure side pressure taking ports in the lower part of the desulfurizing tower; the top of the arc pipe is higher than the communicating part of the desulfurizing tower; the pressure tapping valves are arranged at the ends, communicated with the desulfurization tower, of the upper arc pipe and the lower arc pipe; and the positive pressure chamber and the negative pressure chamber of the differential pressure transmitter are respectively communicated with the bottom end of the negative pressure tapping pipe and the bottom end of the positive pressure tapping pipe through the isolation tank. The differential pressure measuring mechanism can solve the problem that an existing differential pressure measuring mechanism of a desulfurizing tower absorption tower and a regenerating tower is inaccurate in measuring result.

Description

Technical Field

[0001] This utility model relates to the field of natural gas purification technology, specifically to a differential pressure measuring mechanism for a desulfurization tower and a desulfurization tower. Background Technology

[0002] Natural gas purification plants are a crucial link in the development and utilization of sulfur-containing natural gas, primarily responsible for desulfurization, dehydration, and acid gas treatment. The plant setup includes desulfurization units and tail gas treatment units. The desulfurization units consist of desulfurization absorption towers and regeneration towers, typically employing a tray structure, with the regeneration tower generally having more tray layers than the absorption tower. The absorption towers mainly remove harmful substances such as hydrogen sulfide, organic sulfur, and some carbon dioxide from the natural gas, while the regeneration towers are responsible for the regeneration and recycling of the desulfurization solvent. The tail gas treatment unit is responsible for recovering sulfur compounds and ensuring that the tail gas meets emission standards. Its process flow still includes desulfurization, but with the addition of tail gas combustion and process gas cooling steps.

[0003] The pressure differential of the desulfurization tower is one of the important reference parameters for its normal operation and a key parameter for the entire desulfurization unit. By observing the magnitude and trend of the pressure differential, one can directly determine whether liquid retention has occurred in the absorption tower and regeneration tower, whether the system solution is foaming, and the desulfurization effect of the solution. Operators need to make timely adjustments based on the pressure differential to avoid fluctuations in the desulfurization unit, chain shutdowns, or accidents resulting in substandard natural gas products.

[0004] Differential pressure measuring devices are used to monitor the operation of absorption and regeneration towers to ensure their proper functioning. However, liquid accumulation in the pressure tapping lines often occurs during operation, potentially leading to inaccurate differential pressure measurements. Therefore, a detailed analysis of differential pressure measurement in absorption towers is conducted.

[0005] The upper and middle section of the absorber tower is a countercurrent reaction zone where natural gas reacts with the desulfurizing agent from bottom to top. It features multiple trays, each with a liquid collection tray storing the desulfurizing solvent, and a certain amount of gas phase space between the trays. Currently, the common method for differential pressure measurement is to directly connect a differential pressure transmitter to the gas phase space in the upper part of the absorber tower. However, this method has certain drawbacks. Because the gas phase space contains the desulfurizing solution and is in a supersaturated state, and the absorber tower is typically quite tall with long pressure tapping pipes, the desulfurizing solution can precipitate out once the gas medium enters the pressure tapping pipes, causing liquid accumulation. Commonly, this accumulated liquid is condensed desulfurizing agent, which is an organic solvent with strong surface tension. If excessive liquid accumulates, a liquid column will form within the pressure tapping pipes, preventing the liquid from flowing back to the desulfurization tower by gravity, thus affecting the measurement results of the differential pressure transmitter.

[0006] The upper and middle sections of the regeneration tower are regeneration zones where the rich desulfurization solution comes into countercurrent contact with steam flowing from bottom to top, releasing H2S, organic sulfur, and CO2 gases. This section also features multiple trays, each with a liquid collection tray storing the desulfurization solvent, with a certain amount of gas phase space between the trays. However, the problem of liquid accumulation in the differential pressure measuring device's pressure tapping pipeline can affect the differential pressure measurement results. Utility Model Content

[0007] The purpose of this invention is to provide a differential pressure measuring mechanism for desulfurization towers, which can solve the problem of inaccurate measurement results of existing differential pressure measuring mechanisms.

[0008] This utility model is achieved through the following technical solution:

[0009] A differential pressure measuring mechanism for a desulfurization tower includes a negative pressure tapping pipe and a positive pressure tapping pipe, both of which are vertically arranged; an upper arc-shaped pipe, one end of which is connected to the top of the negative pressure tapping pipe, and the other end of which is connected to the upper part of the desulfurization tower, the upper arc-shaped pipe being convex upwards in the middle so that the top of the upper arc-shaped pipe is higher than the connection point with the desulfurization tower; a lower arc-shaped pipe, one end of which is connected to the top of the positive pressure tapping pipe, and the other end of which is connected to the lower part of the desulfurization tower, the lower arc-shaped pipe being convex upwards in the middle so that the top of the lower arc-shaped pipe is higher than the connection point with the desulfurization tower; multiple pressure tapping valves, the pressure tapping valves being located at the ends of the upper and lower arc-shaped pipes connected to the desulfurization tower; and a differential pressure transmitter, the differential pressure transmitter being connected to the bottom end of the negative pressure tapping pipe and the bottom end of the positive pressure tapping pipe respectively.

[0010] Optionally, the end of the upper arc pipe away from the negative pressure tapping pipe is connected to multiple pressure tapping ports of the multi-layer desulfurization tower through multiple horizontally arranged first gas tapping pipes; the end of the lower arc pipe away from the positive pressure tapping pipe is connected to multiple pressure tapping ports of the multi-layer desulfurization tower through multiple horizontally arranged second gas tapping pipes; each first gas tapping pipe and each second gas tapping pipe is equipped with the pressure tapping valve.

[0011] Optionally, the bottom end of the negative pressure tapping tube and the bottom end of the positive pressure tapping tube are respectively connected to an isolation tank, and the two isolation tanks are arranged in parallel.

[0012] Optionally, the bottom of the isolation tank is connected to a drain pipe, and the drain pipe is equipped with a drain valve; the top of the isolation tank located on the negative pressure tapping pipe is connected to the negative pressure side of the differential pressure transmitter, and the top of the isolation tank located on the positive pressure tapping pipe is connected to the positive pressure side of the differential pressure transmitter.

[0013] A desulfurization tower includes: a tower body, which is either a desulfurization absorption tower or a desulfurization regeneration tower. The desulfurization absorption tower body is used for natural gas desulfurization and purification, and the desulfurization regeneration tower body is used for the regeneration of the desulfurizing agent. The upper part of the tower body has multiple negative pressure side pressure taps, and the lower part has multiple positive pressure side pressure taps. A differential pressure measuring mechanism for the desulfurization tower is also included, wherein the first gas tap is corresponding to and connected to each of the negative pressure side pressure taps, and the gas tap is corresponding to and connected to each of the positive pressure side pressure taps.

[0014] Optionally, both the negative pressure side pressure tap and the positive pressure side pressure tap are located on the upper part of the corresponding tray layer of the tower body, so that the negative pressure side pressure tap or the positive pressure side pressure tap is connected to the gas phase space of the corresponding tray layer.

[0015] Optionally, the number of negative pressure side pressure taps is two, and the number of positive pressure side pressure taps is two.

[0016] Optionally, the two negative pressure side taps are respectively located on the top and second-to-last trays of the tower body; the two positive pressure side taps are respectively located on the first and second trays of the tower body.

[0017] Optionally, the tower body is horizontally arranged with multiple trays from bottom to top to divide the tower body into multiple layers; the vertical distance between the negative pressure side pressure tap and / or the positive pressure side pressure tap and the tray located above is ≤100mm.

[0018] Optionally, a wire mesh demister is horizontally provided at the top of the uppermost layer of the tower body, and the vertical distance between the negative pressure side pressure tap that communicates with the uppermost layer of the tower body and the wire mesh demister is ≤100mm.

[0019] Optionally, the highest point of the upper arc tube is level with the highest point of the tower body.

[0020] Optionally, the vertical distance between the highest point of the upper arc tube and the uppermost negative pressure side pressure tap is ≥500mm.

[0021] Optionally, the vertical distance between the highest point of the lower arc tube and the pressure tap on the positive pressure side located above is ≥500mm.

[0022] Compared with the prior art, this utility model has the following advantages and beneficial effects:

[0023] This utility model provides a differential pressure measuring mechanism for a desulfurization tower. It forms a basic differential pressure measuring structure by setting up a negative pressure tapping pipe, a positive pressure tapping pipe, a pressure tapping valve, and a differential pressure transmitter. Since the negative and positive pressure tapping pipes are vertically arranged and connected to the upper and lower parts of the desulfurization tower respectively, a significant pressure difference is created within them. Multiple positive and negative pressure tapping ports are provided to form a solution gravity-flow back-to-tower channel, allowing the solution entering the upper and lower circular arc pipes to quickly flow back into the tower. Furthermore, the upper and lower circular arc pipes prevent the desulfurizing agent from crossing them into the negative or positive pressure tapping pipes when the solution foams or other operational abnormalities occur. Finally, an isolation tank is provided to collect the trace amounts of accumulated liquid formed in the pressure tapping pipes at the rear end of the upper and lower circular arc pipes, thus preventing the formation of liquid columns in the negative or positive pressure tapping pipes that could affect the measured values. Attached Figure Description

[0024] The accompanying drawings, which are included to provide a further understanding of the embodiments of the present invention and form part of this application, do not constitute a limitation thereof. In the drawings:

[0025] Figure 1 This is a schematic diagram of an existing desulfurization tower with a differential pressure measuring mechanism;

[0026] Figure 2 This is a schematic diagram of a desulfurization tower provided in an embodiment of the present invention.

[0027] The attached diagram shows the markings and corresponding component names:

[0028] 1-Tower body; 2-Negative pressure side pressure tap; 3-Positive pressure side pressure tap; 4-Tower tray; 5-Wire mesh demister; 10-Negative pressure tap; 11-Positive pressure tap; 20-Upper arc pipe; 21-First gas tap; 30-Lower arc pipe; 31-Second gas tap; 40-Pressure tap valve; 50-Differential pressure transmitter; 60-Isolation tank; 61-Drain valve. Detailed Implementation

[0029] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be further described in detail below with reference to the embodiments and accompanying drawings. The illustrative embodiments and descriptions of this utility model are only used to explain this utility model and are not intended to limit this utility model.

[0030] Example

[0031] Please refer to Figure 1 and Figure 2This embodiment provides a differential pressure measuring mechanism for a desulfurization tower, including a negative pressure tapping pipe 10 and a positive pressure tapping pipe 11, both of which are vertically arranged; secondly, it includes an upper arc-shaped pipe 20, one end of which is connected to the top of the negative pressure tapping pipe 10, and the other end is used to connect to the upper part of the desulfurization tower. The upper arc-shaped pipe 20 is convex in the middle, so that the top of the upper arc-shaped pipe 20 is higher than the connection point with the desulfurization tower; thirdly, it includes a lower arc-shaped pipe 30, the lower arc-shaped pipe 30... One end of the upper arc pipe 20 is connected to the top of the positive pressure tapping pipe 11, and the other end is used to connect to the lower part of the desulfurization tower. The lower arc pipe 30 is an arc shape with a convex upper part in the middle, so that the top of the lower arc pipe 30 is higher than the connection point with the desulfurization tower. The fourth part includes a plurality of pressure tapping valves 40, which are located at the ends of the upper arc pipe 20 and the lower arc pipe 30 that are connected to the desulfurization tower. The fifth part includes a differential pressure transmitter 50, which is connected to the bottom end of the negative pressure tapping pipe 10 and the bottom end of the positive pressure tapping pipe 11 respectively.

[0032] This utility model provides a differential pressure measuring mechanism for a desulfurization tower. A basic differential pressure measuring structure is formed by setting up a negative pressure tapping pipe 10, a positive pressure tapping pipe 11, a pressure tapping valve 40, and a differential pressure transmitter 50. Since the negative pressure tapping pipe 10 and the positive pressure tapping pipe 11 are vertically arranged and respectively connected to the upper and lower parts of the desulfurization tower, a significant pressure difference is formed within the negative pressure tapping pipe 10 and the positive pressure tapping pipe 11. Multiple positive pressure side taps 3 and negative pressure side taps 2 are provided. This creates a solution gravity return channel to the tower, allowing the solution entering the upper arc pipe 20 and the lower arc pipe 30 to quickly return to the tower. Based on this, by setting the upper arc pipe 20 and the lower arc pipe 30, the desulfurizing agent can be prevented from crossing the upper arc pipe 20 or the lower arc pipe 30 and entering the negative pressure tapping pipe 10 or the positive pressure tapping pipe 11 when the solution in the tower foams or other operational abnormalities occur. This prevents the formation of a liquid column in the negative pressure tapping pipe 10 or the positive pressure tapping pipe 11, which would affect the measured value.

[0033] To further explain the specific shapes of the upper arc pipe 20 and the lower arc pipe 30, the end of the upper arc pipe 20 away from the negative pressure tapping pipe 10 is connected to multiple pressure tapping ports of the multi-layer desulfurization tower through multiple horizontally arranged first gas tapping pipes 21; the end of the lower arc pipe 30 away from the positive pressure tapping pipe 11 is connected to multiple pressure tapping ports of the multi-layer desulfurization tower through multiple horizontally arranged second gas tapping pipes 31; each of the first gas tapping pipes 21 and each of the second gas tapping pipes 31 is equipped with the pressure tapping valve 40.

[0034] To further improve the measurement accuracy of the differential pressure measuring mechanism used in the desulfurization tower, the bottom end of the negative pressure tapping pipe 10 and the bottom end of the positive pressure tapping pipe 11 are respectively connected to an isolation tank 60, and the two isolation tanks 60 are arranged in parallel.

[0035] With the above settings, when the saturated gaseous medium entering the negative pressure tapping pipe 10 or the positive pressure tapping pipe 11 decomposes into solution, due to the small quantity, the solution can rely on its own weight to flow back into the isolation tank 60, thus avoiding the solution from accumulating in the negative pressure tapping pipe 10 or the positive pressure tapping pipe 11 to form a liquid column and affect the measurement value.

[0036] To further ensure the effectiveness of the isolation tank 60, a drain pipe is connected to the bottom of the isolation tank 60, and the drain pipe is equipped with a drain valve 61; the top of the isolation tank 60 located on the negative pressure tapping pipe 10 is connected to the negative pressure side of the differential pressure transmitter 50, and the top of the isolation tank 60 located on the positive pressure tapping pipe 11 is connected to the positive pressure side of the differential pressure transmitter 50.

[0037] With the above settings, the accumulated liquid in the isolation tank 60 can be manually discharged periodically through the drain valve 61 to avoid the isolation tank 60 from becoming saturated and causing it to malfunction.

[0038] Please refer to further details. Figure 2 This embodiment also provides a desulfurization tower, including: a tower body 1, which is a desulfurization absorption tower or a desulfurization regeneration tower. The desulfurization absorption tower body is used for natural gas desulfurization and purification, and the desulfurization regeneration tower body is used for the regeneration of the desulfurizing agent. The upper part of the tower body 1 has multiple negative pressure side pressure taps 2, and the lower part has multiple positive pressure side pressure taps 3. The second part includes the differential pressure measuring mechanism for the desulfurization tower, wherein the first gas tap 21 corresponds to and is connected to the negative pressure side pressure taps 2, and the second gas tap 31 corresponds to and is connected to the positive pressure side pressure taps 3.

[0039] It should be noted that both the negative pressure side pressure tap 2 and the positive pressure side pressure tap 3 are located on the upper part of the corresponding tray layer of the tower body 1, so that the negative pressure side pressure tap 2 or the positive pressure side pressure tap 3 is connected to the gas phase space of the corresponding tray layer.

[0040] Preferably, there are two negative pressure side pressure taps 2 and two positive pressure side pressure taps 3.

[0041] Preferably, the two negative pressure side pressure taps 2 are respectively opened on the top layer and the second to last layer tray of the tower body 1; the two positive pressure side pressure taps 3 are respectively opened on the first layer and the second layer tray of the tower body 1.

[0042] It should be noted that multiple trays 4 are horizontally arranged from bottom to top inside the tower body 1 to divide the tower body 1 into multiple layers; the vertical distance between the negative pressure side pressure tap 2 and / or the positive pressure side pressure tap 3 and the tray 4 located above is ≤100mm.

[0043] It should be noted that a wire mesh demister 5 is horizontally installed at the top of the uppermost layer of the tower body 1, and the vertical distance between the negative pressure side pressure tap 2, which is connected to the uppermost layer of the tower body 1, and the wire mesh demister 5 is ≤100mm.

[0044] It should be noted that the highest point of the upper circular arc tube 20 is level with the highest point of the tower body 1.

[0045] It should be noted that the vertical distance between the highest point of the upper arc tube 20 and the uppermost negative pressure side pressure tap 2 is ≥500mm.

[0046] It should be noted that the vertical distance between the highest point of the lower arc tube 30 and the positive pressure side pressure tap 3 located above is ≥500mm.

[0047] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of this utility model. It should be understood that the above description is only a specific embodiment of this utility model and is not intended to limit the scope of protection of this utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the scope of protection of this utility model.

Claims

1. A differential pressure measuring mechanism for a desulfurization tower, characterized in that, include: Negative pressure tapping tube (10) and positive pressure tapping tube (11), both of which are vertically arranged; The upper arc pipe (20) has one end connected to the top of the negative pressure tapping pipe (10) and the other end connected to the upper part of the desulfurization tower. The upper arc pipe (20) is an arc shape with a convex center, so that the top of the upper arc pipe (20) is higher than the connection point with the desulfurization tower. The lower arc pipe (30) has one end connected to the top of the positive pressure tapping pipe (11) and the other end connected to the lower part of the desulfurization tower. The lower arc pipe (30) is an arc shape with a convex upper part in the middle so that the top of the lower arc pipe (30) is higher than the connection point with the desulfurization tower. Multiple pressure tapping valves (40) are provided at the ends of the upper arc pipe (20) and the lower arc pipe (30) that are connected to the desulfurization tower; Differential pressure transmitter (50) is connected to the bottom end of the negative pressure tapping tube (10) and the bottom end of the positive pressure tapping tube (11).

2. The differential pressure measuring mechanism for a desulfurization tower according to claim 1, characterized in that, The end of the upper arc pipe (20) away from the negative pressure tapping pipe (10) is connected to multiple pressure tapping ports of the desulfurization tower through multiple horizontally arranged first gas tapping pipes (21); The end of the lower arc pipe (30) away from the positive pressure tapping pipe (11) is connected to multiple pressure tapping ports of the multi-layer desulfurization tower through multiple horizontally arranged second gas tapping pipes (31). Each of the first gas intake pipe (21) and each of the second gas intake pipes (31) is equipped with the pressure valve (40).

3. The differential pressure measuring mechanism for a desulfurization tower according to claim 2, characterized in that, The bottom end of the negative pressure tapping tube (10) and the bottom end of the positive pressure tapping tube (11) are respectively connected to an isolation tank (60), and the two isolation tanks (60) are arranged in parallel.

4. The differential pressure measuring mechanism for a desulfurization tower according to claim 3, characterized in that, The bottom end of the isolation tank (60) is connected to a drain pipe, and the drain pipe is equipped with a drain valve (61). The top of the isolation tank (60) located on the negative pressure tapping pipe (10) is connected to the negative pressure side of the differential pressure transmitter (50), and the top of the isolation tank (60) located on the positive pressure tapping pipe (11) is connected to the positive pressure side of the differential pressure transmitter (50).

5. A desulfurization tower, characterized in that, include: Tower body (1), the tower body (1) is a desulfurization absorption tower or a desulfurization regeneration tower. The desulfurization absorption tower is used for natural gas desulfurization and purification, and the desulfurization regeneration tower is used for the regeneration of desulfurizing agent. The upper part of the tower body (1) has multiple negative pressure side pressure taps (2), and the lower part has multiple positive pressure side pressure taps (3). The differential pressure measuring mechanism for a desulfurization tower according to any one of claims 2-4, wherein the first gas sampling pipe (21) corresponds to and is connected to the negative pressure side pressure sampling port (2), and the second gas sampling pipe (31) corresponds to and is connected to the positive pressure side pressure sampling port (3).

6. The desulfurization tower according to claim 5, characterized in that, The negative pressure side pressure tap (2) and the positive pressure side pressure tap (3) are both located on the upper part of the corresponding tray layer of the tower body (1) so that the negative pressure side pressure tap (2) or the positive pressure side pressure tap (3) is connected to the gas phase space of the corresponding tray layer.

7. The desulfurization tower according to claim 6, characterized in that, The number of negative pressure side pressure taps (2) is two, and the number of positive pressure side pressure taps (3) is two.

8. The desulfurization tower according to claim 7, characterized in that, The two negative pressure side pressure taps (2) are respectively opened on the top layer and the second to last layer of the tower body (1); The two positive pressure side pressure taps (3) are respectively opened on the first and second layer trays of the tower body (1).

9. The desulfurization tower according to claim 8, characterized in that, The tower body (1) is horizontally arranged with multiple trays (4) from bottom to top to divide the tower body (1) into multiple layers; The vertical distance between the negative pressure side pressure tap (2) and / or the positive pressure side pressure tap (3) and the tray (4) located above is ≤100mm.

10. The desulfurization tower according to claim 9, characterized in that, The top of the uppermost layer of the tower body (1) is provided with a wire mesh demister (5), and the vertical distance between the negative pressure side pressure tap (2) connected to the uppermost layer of the tower body (1) and the wire mesh demister (5) is ≤100mm.

11. The desulfurization tower according to claim 10, characterized in that, The highest point of the upper circular arc tube (20) is level with the highest point of the tower body (1).

12. The desulfurization tower according to claim 10, characterized in that, The vertical distance between the highest point of the upper circular arc tube (20) and the uppermost negative pressure side pressure tap (2) is ≥500mm.

13. The desulfurization tower according to claim 9, characterized in that, The vertical distance between the highest point of the lower circular arc tube (30) and the positive pressure side pressure tap (3) located above it is ≥500mm.

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