Treatment system for reducing pressure difference of solvent regeneration tower

Abstract

The utility model discloses a treatment system for reducing the pressure difference of a solvent regeneration tower, which comprises a solvent regeneration tower, a first cooling device, a second cooling device and a regeneration tower top reflux tank, gasified hydrogen sulfide and acidic water are separated from the solvent regeneration tower, and the gasified hydrogen sulfide and acidic water are separated from the regeneration tower top reflux tank after passing through the first cooling device and the second cooling device. The acidic water is liquefied, hydrogen sulfide is discharged from the top return tank of the regeneration tower, the acidic water flows back into the solvent regeneration tower, a filter device is arranged between the top return tank of the regeneration tower and the solvent regeneration tower, impurities in the acidic water are purified after passing through the filter device, and the purified acidic water returns to the solvent regeneration tower. The method has the advantages that solid impurities such as iron sulfide mixed in the acidic water are removed, and the conditions of pressure drop of the solvent regeneration tower, poor desulfurization effect of the solvent regeneration tower and the like in the subsequent reaction process are effectively avoided.

Description

Technical Field

[0001] This utility model relates to the chemical industry, and in particular to a treatment system for reducing the pressure difference in a solvent regeneration tower. Background Technology

[0002] In the solvent recycling system of the petrochemical industry, the solvent regeneration tower is a key piece of equipment for achieving hydrogen sulfide removal and amine regeneration. Its core function is to strip the hydrogen sulfide-rich solution: the rich solution enters from the top of the tower and is heated by steam introduced from the bottom, causing the hydrogen sulfide to escape from the liquid phase and exit from the top with the gas phase. The lean solution, after hydrogen sulfide removal, flows out from the bottom of the tower and is recycled to the upstream process via a buffer tank. During this process, the water vapor carried by the gas phase at the top of the tower is cooled by air and water coolers, forming acidic water at a temperature of approximately 20–35°C in the reflux tank at the top of the tower. This acidic water is returned to the first tray at the top of the tower by a reflux pump to maintain the gas-liquid balance within the tower. Theoretically, this recycling system can achieve efficient solvent regeneration, but in actual operation, it faces multiple technical bottlenecks caused by corrosion and impurities.

[0003] The acidic water environment of the top reflux system provides typical conditions for wet hydrogen sulfide corrosion. The solubility of hydrogen sulfide in water increases with decreasing temperature; therefore, the concentration of dissolved hydrogen sulfide in low-temperature acidic water is relatively high. Under these conditions, metal pipes and equipment mainly face two types of corrosion: electrochemical corrosion, where hydrogen sulfide dissolves in water and reacts electrochemically with the iron matrix to generate corrosion products such as ferrous sulfide (FeS), which are suspended in the acidic water as particles; and hydrogen damage, where hydrogen atoms generated during corrosion penetrate into the intergranular spaces of the steel, accumulating at defects to form hydrogen molecules, generating localized high pressure and causing microscopic damage such as hydrogen blistering and hydrogen-induced cracking in the steel, further exacerbating the shedding of metal corrosion products. Simultaneously, mechanical impurities and oil contaminants in the circulating hydrogen of the reaction system may also be carried into the regeneration system through the lean solution, forming "composite impurities" that clog the trays together with iron sulfide particles.

[0004] While the floating valve tray design of the solvent regeneration tower is beneficial for gas-liquid mass transfer, it has poor tolerance to solid particles. With long-term operation, iron sulfide particles and foreign impurities in the acidic water gradually deposit in the gaps between the floating valves and in the downcomers, forming a dense blockage layer. This process triggers a chain reaction: First, the reduced flow area of ​​the trays leads to a significant increase in gas phase resistance, causing the pressure drop in the regeneration tower to surge from tens of kPa during normal operation to hundreds of kPa, forcing the unit to reduce its throughput or increase its operating pressure, increasing equipment fatigue wear. Second, uneven gas-liquid distribution in the trays reduces stripping efficiency, resulting in excessive hydrogen sulfide content in the lean solution, affecting the performance of subsequent desulfurization units, and even leading to substandard product quality. Utility Model Content

[0005] The technical problem to be solved by this utility model is to provide a treatment system that reduces the pressure drop of the solvent regeneration tower. This utility model can remove solid impurities such as iron sulfide mixed in acidic water, and avoid the occurrence of pressure drop in the solvent regeneration tower and deterioration of the desulfurization effect of the solvent regeneration tower in subsequent reaction processes.

[0006] The technical solution adopted by this utility model to solve the above-mentioned technical problems is as follows: a treatment system for reducing the pressure difference of a solvent regeneration tower, comprising a solvent regeneration tower, a first cooling device, a second cooling device, and a regeneration tower top reflux tank. In the solvent regeneration tower, vaporized hydrogen sulfide and acidic water are separated. After passing through the first and second cooling devices, the vaporized hydrogen sulfide and acidic water liquefy, and the hydrogen sulfide is discharged in the regeneration tower top reflux tank. The acidic water is then returned to the solvent regeneration tower. The system is characterized by a filtration device installed between the regeneration tower top reflux tank and the solvent regeneration tower. Impurities in the acidic water are purified after passing through the filtration device, and the purified acidic water is then returned to the solvent regeneration tower.

[0007] A further preferred embodiment of this utility model is as follows: the filtration device includes a first pump body and a second pump body, the first pump body is the pump body in normal use, the second pump body is the standby pump body, and the first pump body and the second pump body are connected in parallel.

[0008] A further preferred embodiment of the present invention is that the filtration device further includes a filter, which is disposed downstream of the first pump body and the second pump body.

[0009] A further preferred embodiment of this utility model is as follows: the filtration device includes a filtration line and a maintenance jumper; the filtration line is used during normal use; during maintenance, it is switched to the maintenance jumper, and the filter is installed in the filtration line.

[0010] A further preferred embodiment of this utility model is as follows: the filter is provided with a filter inlet valve and a filter outlet valve at both ends, and a pressure gauge is provided at both ends of the filter.

[0011] A further preferred embodiment of this utility model is that the filter is a 100-200 mesh filter.

[0012] A further preferred embodiment of this utility model is as follows: the first cooling device includes a tower top air cooler and a first thermometer, and the second cooling device includes a tower top water cooler and a second thermometer.

[0013] A further preferred embodiment of this utility model is: the outlet end of the filter device is connected to the inlet end of the regeneration tower top reflux tank, and a level gauge is installed inside the regeneration tower top reflux tank.

[0014] A further preferred embodiment of this utility model is as follows: a differential pressure gauge is installed on the solvent regeneration tower, and a flow meter is installed on the line connecting the filter device to the solvent regeneration tower.

[0015] This invention achieves multiple technological breakthroughs by adding a filtration device between the reflux tank at the top of the regeneration tower and the solvent regeneration tower, thus creating an impurity interception barrier before the acidic water reflux. Firstly, the filtration device efficiently traps iron sulfide particles, corrosion products, and mechanical impurities carried by circulating hydrogen in the acidic water, preventing these particles from depositing on the floating valve trays of the solvent regeneration tower with the reflux liquid. This addresses the core issue of reduced tray flow area at the source, significantly reducing the risk of increased pressure drop due to blockage in the regeneration tower and maintaining stable gas-liquid mass transfer efficiency within the tower. Secondly, the purified acidic water returning to the tower for circulation reduces interference from impurities in the stripping process, allowing for more complete removal of hydrogen sulfide from the rich solution, significantly reducing the hydrogen sulfide content in the lean solution, improving solvent regeneration efficiency, and ensuring the processing precision and product quality of subsequent process units. Furthermore, the installation of the filtration device reduces the resistance to gas flow within the tower, eliminating the need to compensate for mass transfer efficiency losses by increasing the amount of steam used at the bottom of the tower, thus significantly reducing the energy consumption cost of the equipment; at the same time, it reduces the need for frequent shutdowns and maintenance due to excessive pressure drop, extends the continuous operation cycle of the equipment, and improves production economy. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the structure of this utility model;

[0017] Figure 2 This is a schematic diagram of the filtration device. Detailed Implementation

[0018] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0019] A system for reducing pressure drop in a solvent regeneration tower includes a solvent regeneration tower 1, a first cooling device 2, a second cooling device 3, and a top reflux tank 4. In the solvent regeneration tower 1, vaporized hydrogen sulfide and acidic water are separated. After passing through the first cooling device 2 and the second cooling device 3, the acidic water liquefies, and the hydrogen sulfide is discharged in the top reflux tank 4. The acidic water is then returned to the solvent regeneration tower 1. A filter device 5 is installed between the top reflux tank 4 and the solvent regeneration tower 1. Impurities in the acidic water are purified by the filter device 5, and the purified acidic water is then returned to the solvent regeneration tower 1. The filter device 5 efficiently traps iron sulfide particles, corrosion products, and mechanical impurities carried by circulating hydrogen in the acidic water. This prevents these particles from depositing on the floating valve trays of the solvent regeneration tower 1 with the reflux liquid, thus addressing the core problem of reduced tray flow area at the source. This significantly reduces the risk of increased pressure drop due to blockage in the regeneration tower and maintains stable gas-liquid mass transfer efficiency within the tower. The purified acidic water is returned to the tower for circulation, which reduces the interference of impurities on the stripping process, makes the removal of hydrogen sulfide from the rich solution more complete, significantly reduces the hydrogen sulfide content in the lean solution, improves the solvent regeneration effect, and ensures the processing accuracy and product quality of subsequent process units.

[0020] The filtration unit 5 includes a first pump body 6 and a second pump body 7. The first pump body 6 is the pump body in normal use, and the second pump body 7 is the standby pump body. The first pump body 6 and the second pump body 7 are connected in parallel. The filtration unit 5 adopts a parallel design of the first pump body 6 and the second pump body 7. The filtration unit 5 is located after the first pump body 6. When the first pump body 6 is under maintenance, the second pump body 7 can be activated. This allows for rapid switching during single pump maintenance or failure, avoiding fluctuations in the operation of the regeneration tower caused by reflux interruption and ensuring continuous system operation. At the same time, it allows for maintenance of a single pump without interrupting the process, reducing the risk of personnel exposure to hydrogen sulfide-containing media, enhancing system redundancy, adapting to unit load fluctuations, and maintaining stable reflux flow and operating parameters.

[0021] The filtration device 5 also includes a filter 8, which is located downstream of the first pump body 6 and the second pump body 7. Positioning the filter 8 downstream of the pump body allows the pump's output pressure to increase the fluid velocity through the filter 8, improving impurity interception efficiency, especially for 150-mesh fine particles. The filtration device 5 includes a filter line 9 and a maintenance jumper 10; filter line 9 is used during normal operation; during maintenance, it switches to maintenance jumper 10, with the filter 8 installed on filter line 9. Online maintenance can be performed without stopping the pump, shortening cleaning time, avoiding the high-risk operation of pressure relief during shutdowns in traditional processes, reducing the risk of hydrogen sulfide leakage, improving production continuity and safety, and reducing capacity loss and energy waste caused by shutdowns. The filter 8 has an inlet valve 11 and an outlet valve 12 at both ends, and pressure gauges 13 are installed at both ends of the filter 8. Filter 8 is equipped with an inlet valve 11, an outlet valve 12, and a pressure gauge 13 at both ends. By monitoring the pressure difference between the inlet and outlet, the degree of filter clogging can be determined in real time. When the pressure difference exceeds the threshold, a cleaning prompt is given to prevent excessive clogging from affecting backflow. During maintenance, the valves can cut off the fluid and safely release pressure to prevent backflow of the medium. Combined with cross-line operation, this allows for independent isolation of the filter, ensuring operational safety. Simultaneously, it provides a data interface for the automated control system, supporting differential pressure alarms and automatic switching, improving the level of operational intelligence. Filter 8 uses a 100-200 mesh filter, which can effectively intercept iron sulfide particles and fine impurities.

[0022] The first cooling device 2 includes a top air cooler 14 and a first thermometer 15, and the second cooling device 3 includes a top water cooler 16 and a second thermometer 17. The first cooling device 2 and the second cooling device 3 precisely control the acidic water temperature to 20–35°C, optimizing hydrogen sulfide solubility and reducing solvent loss, thus preventing scaling or crystallization caused by abnormal temperatures. The outlet of the filter device 5 is connected to the inlet of the regeneration tower top reflux tank 4, which is equipped with a level gauge 18. The level gauge 18 in the regeneration tower top reflux tank 4 monitors the liquid level in real time and adjusts the reflux pump flow rate to prevent backflow due to excessively high liquid levels or air suction due to excessively low liquid levels. A differential pressure gauge 21 is installed on the solvent regeneration tower, and a flow meter 22 is installed on the line connecting the filter device to the solvent regeneration tower.

[0023] The above provides a detailed description of the treatment system for reducing the pressure difference in a solvent regeneration tower provided by this utility model. Specific examples have been used to illustrate the principle and implementation of this utility model. The descriptions of the above embodiments are only for the purpose of helping to understand this utility model and its core ideas. It should be noted that those skilled in the art can make several improvements and modifications to this utility model without departing from its principles, and these improvements and modifications also fall within the protection scope of the claims of this utility model.

Claims

1. A system for reducing the pressure differential of a solvent regeneration tower, comprising a solvent regeneration tower, a first cooling device, a second cooling device, and a top reflux tank of the regeneration tower, wherein vaporized hydrogen sulfide and acidic water are separated in the solvent regeneration tower, and after passing through the first and second cooling devices, the acidic water is liquefied and the hydrogen sulfide is discharged in the top reflux tank of the regeneration tower, while the acidic water is refluxed back into the solvent regeneration tower, characterized in that... A filtration device is installed between the top reflux tank of the regeneration tower and the solvent regeneration tower. Impurities in the acidic water are purified after passing through the filtration device, and the purified acidic water is then returned to the solvent regeneration tower.

2. The treatment system for reducing the pressure difference in a solvent regeneration tower according to claim 1, characterized in that... The filtration device includes a first pump body and a second pump body. The first pump body is the pump body in normal use, and the second pump body is the standby pump body. The first pump body and the second pump body are connected in parallel.

3. The treatment system for reducing the pressure difference in a solvent regeneration tower according to claim 2, characterized in that... The filtration device further includes a filter, which is located downstream of the first pump body and the second pump body.

4. The treatment system for reducing the pressure difference in a solvent regeneration tower according to claim 3, characterized in that... The filtration device includes a filtration line and a maintenance jumper; the filtration line is used during normal use; during maintenance, it is switched to the maintenance jumper, and the filter is installed in the filtration line.

5. The treatment system for reducing the pressure difference in a solvent regeneration tower according to claim 3, characterized in that... The filter is equipped with an inlet valve and an outlet valve at both ends, and a pressure gauge is installed at both ends of the filter.

6. The treatment system for reducing the pressure difference in a solvent regeneration tower according to claim 3, characterized in that... The filter used is a 100-200 mesh filter.

7. The treatment system for reducing the pressure difference in a solvent regeneration tower according to claim 1, characterized in that... The first cooling device includes a tower top air cooler and a first thermometer, and the second cooling device includes a tower top water cooler and a second thermometer.

8. The treatment system for reducing the pressure difference in a solvent regeneration tower according to claim 1, characterized in that... The outlet end of the filter device is connected to the inlet end of the regeneration tower top reflux tank, and a level gauge is installed inside the regeneration tower top reflux tank.

9. The treatment system for reducing the pressure difference in a solvent regeneration tower according to claim 1, characterized in that... The solvent regeneration tower is equipped with a differential pressure gauge, and the line connecting the filter device to the solvent regeneration tower is equipped with a flow meter.

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