A dual-stripper hot-coupling system

Abstract

This invention discloses a dual stripping tower thermal coupling system, relating to the field of stripping towers. The system comprises a hot stripping tower, a cold stripping tower, and a control module. The cold stripping tower has a mixing pipe and an outlet pipe in its middle section. A flow guide is positioned between the mixing pipe and the outlet pipe. An overflow weir is slidably mounted on one side of the tray. An adjustment component controls the height and floating range of the overflow weir. The system acquires the average flow rate of the mixed gas within time T. When the average flow rate exceeds a preset baseline value, a first weir height adjustment strategy is executed. After the first weir height adjustment strategy is executed, the average gas flow rate within the current time T is acquired. The difference between this average flow rate and the average gas flow rate within the previous time T is compared with the allowable flow rate fluctuation value. Based on the comparison result, a second weir height adjustment strategy is executed. This dual stripping tower thermal coupling system, through the first weir height adjustment strategy, can adjust the height of the overflow weir to the appropriate height position, improving the mass transfer effect and stripping efficiency on the tray.

Description

Technical Field

[0001] This invention relates to the field of stripping tower technology, specifically a dual stripping tower thermal coupling system. Background Technology

[0002] In traditional oil hydrocracking, the fractionation process involves a dual-tower stripping system consisting of a stripper and a fractionation tower. The stripper feeds two streams of oil: hot low-temperature fractionated oil and cold low-temperature fractionated oil, obtained from the reaction effluent via a separator. Low-pressure steam is introduced through the bottom of the stripper to strip the oil, separating H2S, unstable naphtha, and the bottom oil. Light hydrocarbons containing hydrogen sulfide are removed from the top of the stripper. The bottom oil, after heat exchange, enters the main fractionation tower, where gas-liquid mass transfer separation produces stable light naphtha at the top and hydrotreated tail oil at the bottom.

[0003] Patent CN222821492U discloses a hydrogenation product separation system, including a separation unit, a stripping unit, and a fractionation tower connected sequentially along the direction of the reaction effluent. The separation unit processes the reaction effluent to obtain hot low-density oil and cold low-density oil. The stripping unit includes a first stripping tower and a second stripping tower. Cold low-density oil is input into the inlet of the first stripping tower, and hot low-density oil is input into the inlet of the second stripping tower. The top gas outlet of the second stripping tower is connected to the first stripping tower, and the bottom oil outlet of the first stripping tower is connected to the first feed inlet located in the upper part of the fractionation tower. The bottom oil outlet of the second stripping tower is connected to the feed heater and then to the second feed inlet located in the lower part of the fractionation tower. The fractionation tower separates the materials input into the first feed inlet and the second feed inlet into light and heavy oil products. This application sets up dual stripping towers to strip cold low-grade oil and hot low-grade oil separately, and then feeds them into different trays of the fractionation tower, which avoids the repeated vaporization of some oil products and reduces the load on the feed heater of the fractionation tower.

[0004] The aforementioned patented technology employs two stripping towers to strip the hot low-temperature oil and the cold low-temperature oil respectively, and introduces the overhead gas from the hot stripping tower into the middle of the cold low-temperature oil tower. This allows for the recovery of waste heat from the overhead gas of the hot stripping tower, thereby reducing the high-temperature steam required to be introduced to the bottom of the cold low-temperature oil tower and effectively reducing the heat load of the entire hydrocracking system.

[0005] However, the above-mentioned patent still has the following problems: the flow rate of high-temperature steam introduced at the bottom of the cold stripping tower is relatively stable, while the flow rate of the overhead gas of the hot stripping tower will vary depending on the content of strippable components in the hot low-grade oil. This means that after the overhead gas of the hot stripping tower passes through the middle of the cold stripping tower, the two gases may mix and produce unstable flow rate changes. If the overflow weir height on the trays inside the stripping tower is not adjustable, the liquid level on the trays above the mixed gas cannot be adjusted with the change of the mixed gas flow rate, affecting the mass transfer effect and stripping efficiency on the trays.

[0006] Furthermore, in existing technologies, although the height of the overflow weir on the trays of some stripping towers can be adjusted, this also creates a small gap between the adjustable overflow weir and the tray. If the overflow weir remains at the same height for a long time, the cold low-grade oil will coke and stick in the gap between the overflow weir and the tray, making subsequent height adjustment of the overflow weir extremely inconvenient. Moreover, the method of adjusting the height of the overflow weir is relatively simple and cannot be finely adjusted according to various factors such as changes in the mixed gas flow rate, gas flow fluctuations, and pressure differences above and below the tray. This will also affect the mass transfer effect and stripping efficiency of the tray.

[0007] To address these issues, this invention proposes a dual stripping tower thermal coupling system. Summary of the Invention

[0008] To address the shortcomings of existing technologies, this invention discloses a dual stripping tower thermal coupling system to solve the problems mentioned in the background section.

[0009] A dual stripping tower thermal coupling system includes a hot stripping tower, a cold stripping tower, and a control module. A mixing pipe and an outlet pipe are sequentially installed through the outer wall of the middle part of the cold stripping tower from top to bottom. The end of the outlet pipe away from the cold stripping tower is connected to the mixing pipe, and the mixing pipe is connected to the top of the hot stripping tower. A flow guide shroud is installed inside the cold stripping tower between the mixing pipe and the outlet pipe; A flow sensor is installed inside the mixing tube to monitor the flow rate S of the mixed gas in real time; An overflow weir is slidably positioned on one side of the tray above the mixing pipe; Multiple pressure sensors are located below and above the aforementioned tray; An adjustment component, whose top is connected to the overflow weir and whose bottom is connected to the mixing pipe, is used to control the height and floating range of the overflow weir; Obtain the average flow rate of the mixed gas within time T. When the average flow rate is greater than the preset baseline value, execute the first adjustment strategy for the weir height. After the first weir height adjustment strategy is executed, the average gas flow rate within the current time T is obtained, and the difference between it and the average gas flow rate within the previous time T is compared with the allowable flow fluctuation value. Based on the comparison result, the second weir height adjustment strategy is executed.

[0010] Preferably, the adjustment component includes: The bottom of the fixed cylinder is connected to the flange at one end of the mixing pipe located inside the cold stripping tower. A sliding rod is slidably inserted into a fixed cylinder and its top end is fixedly connected to the overflow weir via an L-shaped rod. The driving component is fixedly installed inside the fixed cylinder; A floating component, which is set inside a fixed cylinder, is used for the elastic connection between the top of the drive output end and the sliding rod.

[0011] Preferably, the floating component includes: A floating disk is located inside the fixed cylinder and is fixedly connected to the bottom of the sliding rod; The connecting piece is fixedly installed at the top of the output end of the drive component and below the floating disk. Connecting cylinders are fixedly installed at both ends of the top of the connecting piece. Two retaining rings are slidably fitted onto two connecting cylinders, with both retaining rings located above the floating disk; Four elastic elements are movably sleeved on the connecting cylinder, allowing the floating disc to elastically float between the connecting plate and the retaining ring.

[0012] Preferably, a fixed pipe is fixedly provided at the top of the fixed cylinder, and two exhaust pipes communicating with its inner cavity are fixedly connected to the outer side of the fixed cylinder. Two symmetrically distributed exhaust slots are opened on the outer circumference of each exhaust pipe. A mounting plate is fixedly provided at the bottom of the drive component. The mounting plate is connected to the bottom flange of the fixed cylinder, and several vents are opened at the bottom of the mounting plate. A fixed cap is fixedly provided at the top of each connecting cylinder.

[0013] Preferably, the bottom of the floating disk has two floating holes, two connecting cylinders are slidably inserted into the two floating holes, two elastic elements are located between the floating disk and the retaining ring, and two other elastic elements are located between the floating disk and the connecting piece.

[0014] Preferably, the inner circle of the retaining ring is fixedly connected to a connecting rod via a slider, the top of the connecting cylinder is provided with a sliding groove adapted to the slider, the slider is slidably connected in the sliding groove, and an electromagnetic plate capable of magnetically attracting the bottom of the connecting rod is fixedly provided at the bottom of the inner cavity of the connecting cylinder.

[0015] Preferably, the first weir height adjustment strategy is as follows: The average flow rate of the mixed gas in the mixing pipe within time T is obtained by a flow sensor. The difference between the average flow rate and the preset flow rate is calculated to obtain the flow increment. The product of the adjustment coefficient 1 / K and the preset flow rate is calculated to obtain the gain flow division benchmark value. The ratio i of the flow increment and the gain flow division benchmark value is calculated. The rise height of the overflow weir is obtained by multiplying the ratio i by the preset height.

[0016] Preferably, the specific determination steps for the second weir height adjustment strategy are as follows: If the difference between the average flow rate in the current time T and the average flow rate in the previous time T is greater than or equal to the allowable flow fluctuation value, the current overflow weir height is maintained for a preset time, and then the average flow rate in the current time T is reacquired. If the difference between the average flow rate in the current time T and the average flow rate in the previous time T is still greater than or equal to the allowable flow fluctuation value, then the first adjustment strategy is executed again. If the difference between the average flow rate in the current time T and the average flow rate in the previous time T is less than the allowable flow fluctuation value, and the difference between the maximum flow rate and the minimum flow rate is less than the preset fluctuation value, and the pressure difference between the upper and lower sides of the tray is greater than or equal to the preset pressure difference value, then the overflow weir is controlled to reduce the preset fine-tuning height. If the difference between the average flow rate in the current time T and the average flow rate in the previous time T is less than the allowable flow fluctuation value, and the difference between the maximum flow rate and the minimum flow rate is greater than or equal to the preset fluctuation value, and the pressure difference between the upper and lower sides of the tray is greater than or equal to the preset pressure difference value, the overflow weir is controlled to reduce the preset fine-tuning height and reduce the automatic up and down floating range of the overflow weir.

[0017] Preferably, during the multiple executions of the first and second weir height adjustment strategies, the number of times the overflow weir height is adjusted, the adjustment height each time, and the adjustment direction each time are obtained within a preset adjustment observation period nT. Based on the multiple adjustment results of the overflow weir, the third weir height adjustment strategy is executed.

[0018] Preferably, the third adjustment strategy for weir height is as follows: If the number of times the overflow weir height is adjusted within the preset adjustment observation period nT is greater than the preset number and the directions of two adjacent adjustments are opposite, and the corresponding height adjustment displacements of two adjacent adjustments are equal, calculate the average value of the heights of the two adjacent adjustments, and adjust the height of the overflow weir to this average value.

[0019] This invention discloses a dual stripping tower thermal coupling system, which has the following beneficial effects: 1. This invention uses a drive component to drive a sliding rod to raise and lower the overflow weir, thereby adjusting the height of the overflow weir relative to the tray. Furthermore, by implementing the first weir height adjustment strategy, the height of the overflow weir can be adjusted to the corresponding height position according to the flow rate of the mixed gas in the mixing pipe, which can improve the mass transfer effect and stripping efficiency of the cold low-separation oil on the tray.

[0020] 2. This invention uses a floating component to elastically connect the driving component and the sliding rod. After the driving component drives the overflow weir to rise and fall, the fluctuation of the mixed gas in the mixing pipe can cause the overflow weir to float up and down slightly. This prevents the overflow weir from staying at the same height for a long time and sticking to one side of the tray, ensuring that the overflow weir can be adjusted in height later.

[0021] 3. This invention reduces the vertical floating range of the overflow weir by using the magnetic attraction of the electromagnetic plate in the floating component to the connecting rod, thus preventing excessive vertical floating of the overflow weir from causing a large amount of liquid to overflow from the tray in a short period of time.

[0022] 4. The present invention uses a second weir height adjustment strategy. After the first weir height adjustment strategy is executed, the overflow weir is controlled to rise or fall significantly or remain stationary based on the change in the average flow rate in the mixing pipe. When the pressure difference between the upper and lower parts of the tray is large, the overflow weir is lowered slightly. When the flow rate fluctuation in the mixing pipe is large, the automatic up and down floating range of the overflow weir is reduced.

[0023] 5. The present invention, through the third adjustment strategy of weir height, after multiple executions of the first and second adjustment strategies of weir height, adjusts the height of the overflow weir again and keeps it unchanged to adapt to the trend of large changes in the average flow rate in the mixing pipe when the average flow rate in the mixing pipe changes significantly, without the need for frequent raising and lowering of the overflow weir. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the structure of the present invention.

[0025] Figure 2 This is a full sectional view of the present invention.

[0026] Figure 3 This is a full sectional view of the middle part of the cold stripping tower of the present invention.

[0027] Figure 4 This is a schematic diagram of the structure of the adjustment component of the present invention.

[0028] Figure 5 This is a full cross-sectional view of the adjustment components before the floating range adjustment of the overflow weir in this invention.

[0029] Figure 6 This is a full sectional view of the adjustment component after the overflow weir floating range is adjusted according to the present invention.

[0030] Figure 7 This is a partial cross-sectional view of the fixing cylinder of the present invention.

[0031] Figure 8 This is a schematic diagram of the sliding rod and overflow weir of the present invention.

[0032] Figure 9 This is a schematic diagram of the structure of the driving component and the retaining ring of the present invention.

[0033] Figure 10 For the present invention Figure 9 Part A of the text is Fang Datong.

[0034] In the diagram: 1. Hot steam stripping tower; 2. Cold stripping tower; 201. Mixing pipe; 202. Outlet pipe; 203. Flow guide; 204. Flow sensor; 205. Pressure sensor; 3. Adjustment components; 4. Fixing cylinder; 401. Fixing tube; 5. Exhaust pipe; 6. Sliding rod; 601. Overflow weir; 602. Floating disc; 603. Floating orifice; 7. Mounting plate; 701. Drive component; 702. Connecting piece; 703. Connecting cylinder; 704. Sliding groove; 705. Electromagnetic plate; 706. Fixing cap; 8. Connecting rod; 801. Slider; 802. Retaining ring; 9. Elastic components. Detailed Implementation

[0035] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0036] according to Figures 1 to 10 As shown, a dual stripping tower thermal coupling system includes a hot stripping tower 1, a cold stripping tower 2, and a control module. The hot stripping tower 1 strips hot low-grade oil, and the cold stripping tower 2 strips cold low-grade oil. The top gas generated by the stripping of the hot stripping tower 1 is introduced into the middle section of the cold stripping tower 2 through a pipeline to supplement heat. The control module is specifically a controller used for signal connection between the flow sensor 204, the pressure sensor 205, the drive component 701, and the electromagnetic plate 705.

[0037] A mixing pipe 201 and an outlet pipe 202 are sequentially installed from top to bottom on the outer wall of the middle section of the cold stripping tower 2. The mixing pipe 201 is connected to the top of the hot stripping tower 1. The end of the mixing pipe 201 away from the cold stripping tower 2 is connected to the pipe flange connected to the top of the hot stripping tower 1, and the end of the outlet pipe 202 away from the cold stripping tower 2 is connected to the mixing pipe 201. The top gas of the hot stripping tower 1 enters the mixing pipe 201. The high-temperature steam introduced from the bottom of the cold stripping tower 2 enters the middle section of the cold stripping tower 2 and then enters the mixing pipe 201 through the outlet pipe 202 to mix with the top gas of the hot stripping tower 1. The mixed gas then enters the mixing pipe 201 located inside the cold stripping tower 2.

[0038] The flow guide 203 is installed in the cold stripping tower 2 between the mixing pipe 201 and the outlet pipe 202. The flow guide 203 is close to the outlet pipe 202. The high-temperature steam entering the middle of the cold stripping tower 2 is guided to the outlet pipe 202 through the flow guide 203, so as to ensure that the two gases can be mixed in the mixing pipe 201.

[0039] The flow sensor 204 is installed in the mixing tube 201 and monitors the flow rate S of the mixed gas in real time. The flow sensor 204 transmits the monitored mixed gas flow rate data to the control module.

[0040] The overflow weir 601 is slidably disposed on one side of the tray above the mixing pipe 201. There are multiple trays in the cold stripping tower 2, but the tray mentioned above specifically refers to the one located above the mixing pipe 201 and closest to the mixing pipe 201. The mixed gas enters the lower part of the tray and then flows upward. The up and down sliding of the overflow weir 601 can adjust the height of the cold low-grade oil liquid level on the tray, thereby improving the mass transfer effect and stripping efficiency of the tray for the cold low-grade oil.

[0041] Multiple pressure sensors 205 are installed below and above the tray. Specifically, there are two pressure sensors 205, which can monitor the pressure values ​​above and below the tray respectively and transmit the pressure data to the control module.

[0042] The control module analyzes and calculates the gas pressure data above and below the tray and the gas flow data in the mixing pipe 201, and controls the start of the drive unit 701 and the electromagnetic plate 705 based on the calculation results.

[0043] The regulating component 3, whose top is connected to the overflow weir 601 and whose bottom is connected to the mixing pipe 201, is used to control the height and floating range of the overflow weir 601. The regulating component 3 controls the rise, fall and floating range of the overflow weir 601 through the control module, the flow sensor 204 and the air pressure sensor 205.

[0044] Adjustment component 3 includes: The fixed cylinder 4 has an open bottom, and its bottom is connected to the flange at one end of the mixing pipe 201 located in the cold stripping tower 2, so that the mixed gas in the mixing pipe 201 can enter the fixed cylinder 4.

[0045] The sliding rod 6 is slidably inserted into the fixed cylinder 4 and its top end is fixedly connected to the overflow weir 601 via an L-rod. The overflow weir 601 rises, falls, and floats up and down as the sliding rod 6 slides up and down in the fixed cylinder 4.

[0046] The driving component 701, specifically an electric push rod, is fixedly installed inside the fixed cylinder 4, and its output end can move up and down.

[0047] A floating component, which is set inside the fixed cylinder 4, is used for the elastic connection between the top of the output end of the drive component 701 and the sliding rod 6. Through the elastic connection between the output end of the drive component 701 and the sliding rod 6 by the floating component, the mounting plate 7 can drive the sliding rod 6 and the overflow weir 601 to rise and fall. Moreover, under the action of the floating component, the distance between the bottom of the sliding rod 6 and the top of the output end of the drive component 701 can be changed, ensuring that the overflow weir 601 can float up and down.

[0048] The sliding rod 6 driven by the drive component 701 moves the overflow weir 601 up or down, thereby adjusting the height of the overflow weir 601 relative to the tray. This allows for adjustment of the liquid level of the cold low-grade oil on the tray as needed, thereby improving the mass transfer effect and stripping efficiency of the cold low-grade oil on the tray.

[0049] A fixed tube 401 is fixedly installed at the top of the fixed cylinder 4. The inside of the fixed tube 401 is connected to the inner cavity of the fixed cylinder 4. The fixed cylinder 4 is located below the tray, while the top of the fixed tube 401 is located above the tray. The bottom of the sliding rod 6 needs to be inserted from the top of the fixed tube 401 and enter the inner cavity of the fixed cylinder 4. Due to the height of the fixed tube 401, the cold low-temperature oil on the tray can be prevented from seeping into the fixed cylinder 4 from the connection between the fixed cylinder 4 and the sliding rod 6. Two exhaust pipes 5 are fixedly connected to the outside of the fixed cylinder 4 and are connected to its inner cavity. Two symmetrically distributed exhaust slots are opened on the outer circumference of each exhaust pipe 5. The mixed gas in the mixing pipe 201 enters the fixed cylinder 4 and then flows into the two exhaust pipes 5. The mixed gas is evenly discharged into the cold stripping tower 2 through the two exhaust pipes 5 to strip the upper part of the cold stripping tower 2.

[0050] The bottom of the drive unit 701 is fixedly provided with a mounting plate 7, which is connected to the bottom flange of the fixed cylinder 4. Several vents are opened at the bottom of the mounting plate 7. The mixed gas in the mixing pipe 201 first passes through the vents and then enters the fixed cylinder 4.

[0051] Floating components include: The floating disk 602 is located in the inner cavity of the fixed cylinder 4 and is fixedly connected to the bottom of the sliding rod 6. There is a small gap between the outer circle side of the floating disk 602 and the circumferential side of the inner cavity of the fixed cylinder 4. When the flow rate of the mixed gas entering the fixed cylinder 4 fluctuates briefly, it can drive the floating disk 602 to float up and down in the fixed cylinder 4. Two through floating holes 603 are opened at the bottom of the floating disk 602.

[0052] The connecting piece 702 is fixedly installed on the top of the output end of the driving component 701 and located below the floating disk 602. Both ends of the top of the connecting piece 702 are fixedly provided with connecting cylinders 703. The output end of the driving component 701 can drive the connecting piece 702 and the connecting cylinders 703 to slide up and down. The two connecting cylinders 703 are respectively slidably inserted into the two floating holes 603.

[0053] Two retaining rings 802 are slidably sleeved on two connecting cylinders 703 respectively. The retaining rings 802 are both located above the floating disk 602. At this time, the floating disk 602 is between the connecting piece 702 and the retaining rings 802.

[0054] A fixing cap 706 is fixedly installed on the top of each connecting cylinder 703. The fixing cap 706 limits the height position of the retaining ring 802 on the connecting cylinder 703, preventing the retaining ring 802 from moving too high and detaching from the connecting cylinder 703.

[0055] Multiple elastic elements 9 are provided, with four in this embodiment. Each elastic element 9 is movably sleeved on the connecting cylinder 703, allowing the floating disk 602 to elastically float between the connecting piece 702 and the retaining ring 802. Two elastic elements 9 are respectively sleeved on the two connecting cylinders 703 and are both located between the floating disk 602 and the retaining ring 802. The other two elastic elements 9 are respectively sleeved on the two connecting cylinders 703 and are both located between the floating disk 602 and the connecting piece 702. Through the elastic support of multiple elastic elements 9 between the floating disk 602, the connecting piece 702 and the retaining ring 802, the driving member 701 can drive the connecting piece 702, the floating disk 602 and the retaining ring 802 to move up or down. Furthermore, when the mixed gas in the mixing pipe 201 fluctuates, it can drive the floating disk 602 to bounce up and down between the connecting piece 702 and the retaining ring 802.

[0056] By connecting the output end of the drive component 701 to the sliding rod 6 through the floating component, after the drive component 701 drives the sliding rod 6 and the overflow weir 601 to rise and fall, the floating disk 602 drives the overflow weir 601 to float slightly up and down on one side of the tray as the mixed gas in the mixing pipe 201 fluctuates. This prevents the overflow weir 601 from maintaining the same height for a long time, thereby preventing the overflow weir 601 from sticking to the side of the tray due to coking of cold low-separation oil, and ensuring that the overflow weir 601 can be adjusted in height later.

[0057] A connecting rod 8 is fixedly connected to the inner circle of the retaining ring 802 via a slider 801. The connecting rod 8 is made of metal that can be magnetized by the electromagnetic plate 705. The top of the connecting cylinder 703 has a sliding groove 704 that matches the slider 801. The slider 801 is slidably connected in the sliding groove 704. The connecting rod 8 is located inside the connecting cylinder 703. Through the sliding cooperation between the slider 801 and the sliding groove 704, the connecting rod 8 can be driven to move downward outside the connecting cylinder 703 when it moves downward inside the connecting cylinder 703. An electromagnetic plate 705 that can magnetically attract the bottom of the connecting rod 8 is fixedly installed at the bottom of the inner cavity of the connecting cylinder 703. The start and stop of the electromagnetic plate 705 is controlled by the control module. When the electromagnetic plate 705 is energized, it generates magnetic force, which can magnetically attract the connecting rod 8, thereby controlling the downward movement of the connecting rod 8 and the retaining ring 802, thereby reducing the gap between the retaining ring 802 and the connecting plate 702, and thus reducing the vertical floating range of the floating disk 602 and the overflow weir 601.

[0058] The magnetic attraction of the connecting rod 8 by the electromagnetic plate 705 can drive the retaining ring 802 to move downward on the connecting cylinder 703. This can reduce the vertical floating range of the floating plate 602 and the overflow weir 601 when the flow rate of the mixed gas fluctuates drastically, and prevent the overflow weir 601 from floating too much vertically, thus preventing the overflow weir 601 from dropping too much height suddenly and causing a large amount of liquid to overflow from the tray in a short period of time.

[0059] The multi-stage adjustment strategy for the height of the overflow weir 601 is as follows: The average flow rate of the mixed gas within time T is obtained. When the average flow rate is greater than the preset baseline value, the first adjustment strategy for weir height is executed.

[0060] The first adjustment strategy for weir height is as follows: The average flow rate of the mixed gas in the mixing tube 201 within time T is obtained by the flow sensor 204. The difference between the average flow rate and the preset flow rate value is calculated to obtain the flow increment. The product of the adjustment coefficient 1 / K and the preset flow rate value is calculated to obtain the gain flow division benchmark value. K is a positive integer and is selected according to the actual working conditions. The ratio i of the flow increment and the gain flow division benchmark value is calculated. The ratio i is multiplied by the preset height to obtain the height of the overflow weir 601. According to the above calculation, it can be easily concluded that the larger the average flow rate of the mixed gas in the mixing tube 201 within time T, the higher the overflow weir 601 needs to be adjusted to, thereby increasing the liquid level on the tray, increasing the gas-liquid mass transfer time, and improving the stripping efficiency.

[0061] By implementing the first weir height adjustment strategy, the height of the overflow weir 601 can be adjusted to the corresponding height position according to the flow rate of the mixed gas in the mixing pipe 201, so that the liquid level on the tray matches the flow rate of the mixed gas in the mixing pipe 201, thereby improving the stripping efficiency.

[0062] After the first weir height adjustment strategy is executed, the average gas flow rate within the current time T is obtained, and the difference between it and the average gas flow rate within the previous time T is compared with the allowable flow fluctuation value. Based on the comparison result, the second weir height adjustment strategy is executed.

[0063] The specific steps for determining the second adjustment strategy for weir height are as follows: If the difference between the average flow rate in the current time T and the average flow rate in the previous time T is greater than or equal to the allowable flow fluctuation value, after maintaining the current height of the overflow weir 601 for a preset time, the average flow rate in the current time T is reacquired. If the difference between the average flow rate in the current time T and the average flow rate in the previous time T is still greater than or equal to the allowable flow fluctuation value, this indicates that the flow rate of the mixed gas in the mixing pipe 201 has increased or decreased significantly and can maintain the current stable flow rate. At this time, the current height of the overflow weir 601 is too low or too high, and it is necessary to adjust the height of the overflow weir 601 significantly again. Then, the first adjustment strategy is executed again to make the overflow weir 601 rise or fall by a large displacement.

[0064] If the difference between the average flow rate in the current time T and the average flow rate in the previous time T is less than the allowable flow fluctuation value, and the difference between the maximum and minimum flow rates is less than the preset fluctuation value, and the pressure difference between the upper and lower sides of the tray is greater than or equal to the preset pressure difference value, this situation indicates that the flow rate of the mixed gas in the mixing pipe 201 has only changed slightly. However, the height of the overflow weir 601 is too high, resulting in a large pressure difference between the upper and lower sides of the tray. At the same time, the small flow fluctuation caused by the difference between the maximum and minimum flow rates can cause the floating disk 602 and the overflow weir 601 to float up and down. In this case, the overflow weir 601 is controlled to lower the preset fine-tuning height so that the overflow weir 601 only drops a small distance.

[0065] If the difference between the average flow rate in the current time T and the average flow rate in the previous time T is less than the allowable flow fluctuation value, and the difference between the maximum and minimum flow rates is greater than or equal to the preset fluctuation value, and the pressure difference between the upper and lower sides of the tray is greater than or equal to the preset pressure difference value, this situation indicates that the flow rate of the mixed gas in the mixing pipe 201 has only changed slightly. However, the height of the overflow weir 601 is too high, resulting in a large pressure difference between the upper and lower sides of the tray. Moreover, the large flow fluctuation caused by the difference between the maximum and minimum flow rates may cause the floating plate 602 and the overflow weir 601 to float up and down in a large range. In this case, the overflow weir 601 is controlled to lower the preset fine-tuning height so that the overflow weir 601 only drops a small distance and the automatic up and down floating range of the overflow weir 601 is reduced.

[0066] There are two other scenarios: If the difference between the average flow rate in the current time T and the average flow rate in the previous time T is less than the allowable flow fluctuation value, and the difference between the maximum and minimum flow rates is less than the preset fluctuation value, and the pressure difference between the upper and lower sides of the tray is less than the preset pressure difference value, this indicates that the current height position of the overflow weir 601 is appropriate and no adjustment is needed.

[0067] If the difference between the average flow rate in the current time T and the average flow rate in the previous time T is less than the allowable flow fluctuation value, and the difference between the maximum flow rate and the minimum flow rate is greater than or equal to the preset fluctuation value, and the pressure difference between the upper and lower sides of the tray is less than the preset pressure difference value, the current height of the overflow weir 601 does not need to be adjusted; only the automatic up-and-down floating range of the overflow weir 601 needs to be reduced.

[0068] By implementing the second weir height adjustment strategy, after the first weir height adjustment strategy is executed, the overflow weir 601 can be controlled to rise or fall significantly or remain stationary based on the change in the average flow rate in the mixing pipe 201. When the pressure difference between the upper and lower parts of the tray is large, the overflow weir 601 is lowered slightly. When the flow rate fluctuation in the mixing pipe 201 is large, the automatic up and down floating range of the overflow weir 601 is reduced.

[0069] During the multiple executions of the first and second weir height adjustment strategies, the number of height adjustments of the overflow weir 601, the adjustment height each time, and the adjustment direction each time are obtained within the preset adjustment observation period nT. Based on the multiple adjustment results of the overflow weir 601, the third weir height adjustment strategy is executed. The third weir height adjustment strategy needs to be observed and monitored based on the multiple execution results of the first and second weir height adjustment strategies within a certain period of time before determining whether to execute it.

[0070] The third adjustment strategy for weir height is as follows: When the number of times the overflow weir 601 height is adjusted within the preset adjustment observation period nT is greater than the preset number, and the directions of two adjacent adjustments are opposite, while the corresponding height adjustment displacements of two adjacent adjustments are equal, this indicates that although the average flow rate in the mixing tube 201 has been changing significantly over this relatively long period, the overall trend is relatively regular: average flow rate increases – average flow rate decreases – average flow rate increases – average flow rate decreases. This requires the height of the overflow weir 601 to be frequently adjusted back and forth with large fluctuations. However, during multiple large fluctuations in the overflow weir 601, excessive liquid overflow from the tray can occur. Calculating the average height of two adjacent adjustments and adjusting the height of the overflow weir 601 to this average value allows the height of the overflow weir 601 to be adjusted to better suit this change in average flow rate and remain constant. Subsequently, when the flow rate in the mixing tube 201 maintains this pattern of change for a long time, it is not necessary to control the overflow weir 601 to frequently adjust back and forth with large fluctuations.

[0071] By employing the third weir height adjustment strategy, after multiple executions of the first and second weir height adjustment strategies, when a significant trend change occurs in the average flow rate within the mixing pipe 201, the height of the overflow weir 601 can be adjusted again and kept constant to adapt to this change pattern. This eliminates the need for frequent raising and lowering of the overflow weir 601, ensuring production stability.

[0072] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of this invention is defined by the appended claims and their equivalents.

Claims

1. A dual-stripping-tower thermal coupling system, comprising a hot stripping tower, a cold stripping tower, and a control module, characterized in that: The outer wall of the middle section of the cold stripping tower is provided with a mixing pipe and an outlet pipe running through it from top to bottom. The end of the outlet pipe away from the cold stripping tower is connected to the mixing pipe, and the mixing pipe is connected to the top of the hot stripping tower. A flow guide shroud is installed inside the cold stripping tower between the mixing pipe and the outlet pipe; A flow sensor is installed inside the mixing tube to monitor the flow rate S of the mixed gas in real time; An overflow weir is slidably positioned on one side of the tray above the mixing pipe; Multiple pressure sensors are located below and above the aforementioned tray; An adjustment component, whose top is connected to the overflow weir and whose bottom is connected to the mixing pipe, is used to control the height and floating range of the overflow weir; Obtain the average flow rate of the mixed gas within time T. When the average flow rate is greater than the preset baseline value, execute the first adjustment strategy for the weir height. After the first weir height adjustment strategy is executed, the average gas flow rate within the current time T is obtained, and the difference between it and the average gas flow rate within the previous time T is compared with the allowable flow fluctuation value. Based on the comparison result, the second weir height adjustment strategy is executed.

2. The dual stripping tower thermal coupling system according to claim 1, characterized in that: The adjustment component includes: The bottom of the fixed cylinder is connected to the flange at one end of the mixing pipe located inside the cold stripping tower. A sliding rod is slidably inserted into a fixed cylinder and its top end is fixedly connected to the overflow weir via an L-shaped rod. The driving component is fixedly installed inside the fixed cylinder; A floating component, which is set inside a fixed cylinder, is used for the elastic connection between the top of the drive output end and the sliding rod.

3. The dual stripping tower thermal coupling system according to claim 2, characterized in that: The floating component includes: A floating disk is located inside the fixed cylinder and is fixedly connected to the bottom of the sliding rod; The connecting piece is fixedly installed at the top of the output end of the drive component and below the floating disk. Connecting cylinders are fixedly installed at both ends of the top of the connecting piece. Two retaining rings are slidably fitted onto two connecting cylinders, with both retaining rings located above the floating disk; Multiple elastic elements are provided, all of which are movably sleeved on the connecting cylinder, allowing the floating disc to elastically float between the connecting plate and the retaining ring.

4. The dual stripping tower thermal coupling system according to claim 2, characterized in that: The top of the fixed cylinder is fixedly equipped with a fixed pipe, and two exhaust pipes communicating with its inner cavity are fixedly connected to the outside of the fixed cylinder. Two symmetrically distributed exhaust slots are opened on the outer circumference of each exhaust pipe. The bottom of the drive component is fixedly equipped with a mounting plate, which is connected to the bottom flange of the fixed cylinder. Several vents are opened at the bottom of the mounting plate. The top of the connecting cylinder is fixedly equipped with a fixed cap.

5. A dual stripping tower thermal coupling system according to claim 3, characterized in that: The bottom of the floating disk has two floating holes, and two connecting cylinders are slidably inserted into the two floating holes respectively. Two elastic elements are located between the floating disk and the retaining ring, and two other elastic elements are located between the floating disk and the connecting piece.

6. The dual stripping tower thermal coupling system according to claim 5, characterized in that: The inner circle of the retaining ring is fixedly connected to the connecting rod by a slider. The top of the connecting cylinder is provided with a sliding groove that matches the slider. The slider is slidably connected in the sliding groove. An electromagnetic plate that can magnetically attract the bottom of the connecting rod is fixedly provided at the bottom of the inner cavity of the connecting cylinder.

7. A dual stripping tower thermal coupling system according to claim 1, characterized in that: The first adjustment strategy for weir height is specifically as follows: The average flow rate of the mixed gas in the mixing pipe within time T is obtained by a flow sensor. The difference between the average flow rate and the preset flow rate is calculated to obtain the flow increment. The product of the adjustment coefficient 1 / K and the preset flow rate is calculated to obtain the gain flow division benchmark value. The ratio i of the flow increment and the gain flow division benchmark value is calculated. The rise height of the overflow weir is obtained by multiplying the ratio i by the preset height.

8. A dual stripping tower thermal coupling system according to claim 7, characterized in that: The specific determination steps for the second weir height adjustment strategy are as follows: If the difference between the average flow rate in the current time T and the average flow rate in the previous time T is greater than or equal to the allowable flow fluctuation value, the current overflow weir height is maintained for a preset time, and then the average flow rate in the current time T is reacquired. If the difference between the average flow rate in the current time T and the average flow rate in the previous time T is still greater than or equal to the allowable flow fluctuation value, then the first adjustment strategy is executed again. If the difference between the average flow rate in the current time T and the average flow rate in the previous time T is less than the allowable flow fluctuation value, and the difference between the maximum flow rate and the minimum flow rate is less than the preset fluctuation value, and the pressure difference between the upper and lower sides of the tray is greater than or equal to the preset pressure difference value, then the overflow weir is controlled to reduce the preset fine-tuning height. If the difference between the average flow rate in the current time T and the average flow rate in the previous time T is less than the allowable flow fluctuation value, and the difference between the maximum flow rate and the minimum flow rate is greater than or equal to the preset fluctuation value, and the pressure difference between the upper and lower sides of the tray is greater than or equal to the preset pressure difference value, the overflow weir is controlled to reduce the preset fine-tuning height and reduce the automatic up and down floating range of the overflow weir.

9. A dual stripping tower thermal coupling system according to claim 8, characterized in that: During the multiple executions of the first and second weir height adjustment strategies, the number of times the overflow weir height is adjusted, the adjustment height each time, and the adjustment direction each time are obtained within a preset adjustment observation period nT. Based on the multiple adjustment results of the overflow weir, the third weir height adjustment strategy is executed.

10. A dual stripping tower thermal coupling system according to claim 9, characterized in that: The third adjustment strategy for weir height is specifically as follows: If the number of times the overflow weir height is adjusted within the preset adjustment observation period nT is greater than the preset number and the directions of two adjacent adjustments are opposite, and the corresponding height adjustment displacements of two adjacent adjustments are equal, calculate the average value of the heights of the two adjacent adjustments, and adjust the height of the overflow weir to this average value.

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