Sewage steam stripping and solvent regeneration heat self-circulation system

Abstract

The invention provides a sewage stripping and solvent regeneration heat self-circulation system. The system comprises a sewage stripping tower; a purified water inlet of the sewage stripping reboiler is connected with a purified water outlet of the sewage stripping tower, and a first stripping steam outlet of the sewage stripping reboiler is connected with a first gas phase return port of the sewage stripping tower; a solvent regeneration tower; a lean amine liquid inlet of the solvent reboiler is connected with a lean amine liquid outlet of the solvent regeneration tower, and a second stripping steam outlet of the solvent reboiler is connected with a second gas phase return port of the solvent regeneration tower; a hot side inlet of the first steam generator and / or the second steam generator is connected with the purified water outlet / the lean amine liquid outlet, and a cold side inlet of the first steam generator and / or the second steam generator is connected with the condensed water outlet; a vapor phase inlet of the vapor compression unit is connected with a first gas outlet of the first vapor generator and / or a second gas outlet of the second vapor generator, and a vapor phase outlet of the vapor compression unit is connected with the first vapor inlet and the second vapor inlet. The system can deeply recover waste heat of materials in the tower and waste heat of condensed water of the reboiler, and steam consumption of the system is reduced.

Description

Technical Field

[0001] This application relates to the field of energy conservation and environmental protection technology, specifically to a wastewater stripping and solvent regeneration heat self-circulation system. Background Technology

[0002] In the processes of petroleum refining and coal chemical production, large quantities of acidic water and amine-rich solutions containing acidic components such as H2S (hydrogen sulfide), NH3 (ammonia), and CO2 (carbon dioxide) are generated. Wastewater stripping units and solvent regeneration units are the core equipment for treating acidic water and amine-rich solutions.

[0003] Existing processes typically use high-quality steam input from a reboiler as a heat source to heat the liquid inside the tower, generating stripping steam which is then delivered to the wastewater stripping unit and solvent regeneration unit to remove acidic components. In existing processes, the high-temperature condensate discharged from the reboiler is directly cooled by flash evaporation and air cooling, resulting in insufficient heat recovery and utilization. Simultaneously, the high-temperature materials inside the tower (purified water or lean amine solution) still carry a significant amount of residual heat after heat exchange with the raw materials, which is not fully recovered, leading to persistently high energy consumption in existing processes.

[0004] Therefore, how to deeply recover the waste heat of materials in the tower and the waste heat of reboiler condensate, and reduce steam consumption, has become a technical problem that urgently needs to be solved in this field.

[0005] It should be noted that the information disclosed in the background section above is only used to enhance the understanding of the background of this application, and therefore may include information that does not constitute prior art known to those skilled in the art. Summary of the Invention

[0006] This application provides a wastewater stripping and solvent regeneration heat self-circulation system, which can deeply recover the waste heat of materials in the tower and the waste heat of reboiler condensate, and reduce the system steam consumption.

[0007] One aspect of this application provides a wastewater stripping and solvent regeneration thermal self-circulation system, comprising: a wastewater stripping tower configured to receive acidic water, remove acidic components by stripping steam, and output purified water and acidic gas; a wastewater stripping reboiler having a first steam inlet, a purified water inlet, a first stripping steam outlet, and a first condensate outlet, wherein the purified water inlet is connected to the purified water outlet of the wastewater stripping tower, and the first stripping steam outlet is connected to a first gas phase return port of the wastewater stripping tower; a solvent regeneration tower configured to receive a rich amine solution, regenerate it by stripping steam, and output a lean amine solution and acidic gas; and a solvent reboiler having a second steam inlet, a lean amine solution inlet, a second stripping steam outlet, and a second condensate outlet, wherein the lean amine solution inlet is connected to the ... and a solvent regeneration tower configured to receive a rich amine solution, regenerate it by stripping steam, and output a lean amine solution and acidic gas; and a solvent reboiler having a second steam inlet, a lean amine solution inlet, a second stripping steam outlet, and a second condensate outlet, wherein the lean amine solution inlet is connected The tower is connected to the lean amine liquid outlet, and the second stripping steam outlet is connected to the second gas phase return port of the solvent regeneration tower; a first steam generator and / or a second steam generator, wherein: the first hot-side inlet of the first steam generator is connected to the purified water outlet, the first cold-side inlet of the first steam generator is connected to the first condensate outlet, the second hot-side inlet of the second steam generator is connected to the lean amine liquid outlet, and the second cold-side inlet of the second steam generator is connected to the second condensate outlet; a vapor compression unit, wherein the vapor phase inlet of the vapor compression unit is connected to the first gas outlet of the first steam generator and / or the second gas outlet of the second steam generator, and the vapor phase outlet of the vapor compression unit is connected to the first steam inlet and the second steam inlet.

[0008] In some embodiments, the wastewater stripping and solvent regeneration heat self-circulation system further includes a first condensate pump and / or a second condensate pump, wherein: the first condensate pump is connected between the first cold-side outlet of the first steam generator and the liquid phase inlet of the steam compression unit, and the second condensate pump is connected between the second cold-side outlet of the second steam generator and the liquid phase inlet of the steam compression unit; and the outlets of the first condensate pump and / or the second condensate pump are also connected to a condensate outlet.

[0009] In some embodiments, the wastewater stripping and solvent regeneration heat self-circulation system further includes: a first liquid level regulating valve connected to a pipeline from the first cold side outlet to the first condensate pump; and / or, a second liquid level regulating valve connected to a pipeline from the second cold side outlet to the second condensate pump; and / or, a desuperheating water regulating valve connected to a pipeline from the outlet of the first condensate pump and / or the second condensate pump to the liquid phase inlet.

[0010] In some embodiments, the wastewater stripping and solvent regeneration heat self-circulation system further includes: a first inlet / outlet heat exchanger having a first heat exchange pipeline and a second heat exchange pipeline, the first heat exchange pipeline being thermally coupled to the second heat exchange pipeline, the first heat exchange pipeline being connected between the first hot-side outlet of the first steam generator and the purified water outlet, and the second heat exchange pipeline being connected between the acidic water inlet and the acidic water inlet of the wastewater stripping tower; and a second inlet / outlet heat exchanger having a third heat exchange pipeline and a fourth heat exchange pipeline, the third heat exchange pipeline being thermally coupled to the fourth heat exchange pipeline, the third heat exchange pipeline being connected between the second hot-side outlet of the second steam generator and the lean amine liquid outlet, and the fourth heat exchange pipeline being connected between the rich amine liquid inlet and the rich amine liquid inlet of the solvent regeneration tower.

[0011] In some embodiments, the wastewater stripping and solvent regeneration heat self-circulation system further includes: a first raw material preheating heat exchanger having a fifth heat exchange pipeline and a sixth heat exchange pipeline, the fifth heat exchange pipeline being thermally coupled to the sixth heat exchange pipeline, the fifth heat exchange pipeline being connected between the second heat exchange pipeline and the acidic water inlet, and the sixth heat exchange pipeline being connected between the first acidic gas outlet and the first acidic gas external outlet of the wastewater stripping tower; a first reflux tank and a first reflux pump connected in series, wherein the first reflux tank is connected to the sixth heat exchange pipeline, the first reflux pump is connected to the first reflux inlet of the wastewater stripping tower, and the first reflux tank is also connected to the first acidic gas external outlet.

[0012] In some embodiments, the wastewater stripping and solvent regeneration heat self-circulation system further includes: a first cooling device connected between the first heat exchange pipeline and the purified water outlet; and / or, a second cooling device connected between the sixth heat exchange pipeline and the first reflux tank.

[0013] In some embodiments, the wastewater stripping and solvent regeneration heat self-circulation system further includes: a second raw material preheating heat exchanger having a seventh heat exchange pipeline and an eighth heat exchange pipeline, the seventh heat exchange pipeline being thermally coupled to the eighth heat exchange pipeline, the seventh heat exchange pipeline being connected between the fourth heat exchange pipeline and the amine-rich liquid inlet, and the eighth heat exchange pipeline being connected between the second acid gas outlet and the second acid gas external outlet of the solvent regeneration tower; a second reflux tank and a second reflux pump connected in series, wherein the second reflux tank is connected to the eighth heat exchange pipeline, the second reflux pump is connected to the second reflux inlet of the solvent regeneration tower, and the second reflux tank is also connected to the second acid gas external outlet.

[0014] In some embodiments, the wastewater stripping and solvent regeneration heat self-circulation system further includes: a third cooling device connected between the third heat exchange pipeline and the lean amine liquid outlet; and / or, a fourth cooling device connected between the eighth heat exchange pipeline and the second reflux tank.

[0015] In some embodiments, the wastewater stripping and solvent regeneration heat self-circulation system further includes: a first condensate control valve connected to the pipeline from the first condensate outlet to the first cold-side inlet; and / or, a second condensate control valve connected to the pipeline from the second condensate outlet to the second cold-side inlet; and / or, a first flow regulating valve connected to the pipeline between the external steam inlet and the first steam inlet; and / or, a second flow regulating valve connected to the pipeline between the external steam inlet and the second steam inlet; and / or, a third flow regulating valve connected to the pipeline between the gas phase outlet and the first steam inlet; and / or, a fourth flow regulating valve connected to the pipeline between the gas phase outlet and the second steam inlet.

[0016] In some embodiments, the first acid gas outlet is located at the top of the wastewater stripping tower, and the purified water outlet is located at the bottom of the wastewater stripping tower; the operating temperature at the top of the wastewater stripping tower is in the range of 105°C to 125°C, and the operating pressure at the top of the wastewater stripping tower is in the range of 0.1 MPag to 0.2 MPag; the operating temperature at the bottom of the wastewater stripping tower is in the range of 120°C to 135°C, and the operating pressure at the bottom of the wastewater stripping tower is in the range of 0.12 MPag to 0.25 MPag; and / or, the second acid gas outlet is located at the top of the solvent regeneration tower, and the lean amine liquid outlet is located at the solvent regeneration tower. The operating temperature at the top of the solvent regeneration tower is in the range of 95°C to 110°C, and the operating pressure at the top of the solvent regeneration tower is in the range of 0.05 MPa to 0.15 MPa; the operating temperature at the bottom of the solvent regeneration tower is in the range of 115°C to 130°C, and the operating pressure at the bottom of the solvent regeneration tower is in the range of 0.07 MPa to 0.2 MPa; and / or, the condensate temperature output from the wastewater stripping reboiler and the solvent reboiler is in the range of 130°C to 150°C; and / or, the steam generation temperature of the first steam generator and / or the second steam generator is in the range of 90°C to 105°C.

[0017] The advantages of this application compared to the prior art may include: The wastewater stripping and solvent regeneration heat self-circulation system of this application, through the cooperation of a wastewater stripping tower, a wastewater stripping reboiler, a solvent regeneration tower, a solvent reboiler, a first steam generator and / or a second steam generator, and a steam compression unit, can achieve: Deep waste heat recovery: The waste heat from the purified water of the wastewater stripping tower, the waste heat from the lean amine liquid of the solvent regeneration tower, and the waste heat from the condensate of the wastewater stripping reboiler / solvent reboiler are recovered in two ways and low-pressure steam is produced through the first steam generator / second steam generator. Thermal self-circulation: The self-generated steam from the first steam generator / second steam generator is compressed by the steam compression unit and reused in the wastewater stripping reboiler / solvent reboiler, replacing part of the externally supplied high-quality steam, realizing a closed-loop circulation of heat within the system and reducing the consumption of externally supplied steam; Energy saving and consumption reduction: According to experimental data, the wastewater stripping and solvent regeneration heat self-circulation system of this application can reduce fresh steam consumption by more than 30%, achieve a comprehensive energy saving rate of 31.7% to 33.8%, and reduce operating costs by more than 27%. Structural compatibility: The wastewater stripping tower and solvent regeneration tower can be configured with a first steam generator / second steam generator independently as needed, while sharing a single steam compression unit, thus reducing investment costs.

[0018] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and do not limit this application. Attached Figure Description

[0019] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application. It is obvious that the drawings described below are merely some embodiments of this application, and those skilled in the art can obtain other drawings based on these drawings without any inventive effort.

[0020] Figure 1 This is a schematic diagram of the wastewater stripping and solvent regeneration heat self-circulation system in the embodiments of this application; Figure 2 yes Figure 1 A partially enlarged structural diagram. Detailed Implementation

[0021] Exemplary embodiments will now be described more fully with reference to the accompanying drawings. However, these exemplary embodiments can be implemented in many forms and should not be construed as limited to those described herein. Rather, these embodiments are provided to make this application more comprehensive and complete, and to fully convey the concept of the exemplary embodiments to those skilled in the art.

[0022] The accompanying drawings are merely illustrative of this application and are not necessarily drawn to scale. The same reference numerals in the drawings denote the same or similar parts, and therefore, repeated descriptions of them will be omitted.

[0023] The use of terms such as "first," "second," and similar words in the specific description does not indicate any order, quantity, or importance, but is merely used to distinguish different components. Furthermore, in the description of this application, unless otherwise expressly specified and limited, the term "connection" should be interpreted broadly, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, or it can refer to the internal connection of two elements.

[0024] It should be noted that, unless otherwise specified, the embodiments of this application and the features in different embodiments can be combined with each other. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0025] Figure 1 The structure of the wastewater stripping and solvent regeneration heat self-circulation system is illustrated. Figure 2 The diagram illustrates a magnified structure of a portion of the wastewater stripping and solvent regeneration heat self-circulation system, combined with... Figure 1 and Figure 2 As shown in the embodiments of this application, the wastewater stripping and solvent regeneration heat self-circulation system may include: Wastewater stripping tower 110 is configured to receive acidic water, remove acidic components through stripping steam, and output purified water and acidic gas; The wastewater stripping reboiler 120 has a first steam inlet 121, a purified water inlet 122, a first stripping steam outlet 123 and a first condensate outlet 124, wherein the purified water inlet 122 is connected to the purified water outlet 111 of the wastewater stripping tower 110, and the first stripping steam outlet 123 is connected to the first gas phase return port 112 of the wastewater stripping tower 110. Solvent regeneration tower 210 is configured to receive rich amine liquid, regenerate it by stripping steam, and output lean amine liquid and acidic gas; The solvent reboiler 220 has a second steam inlet 221, a lean amine liquid inlet 222, a second stripping steam outlet 223, and a second condensate outlet 224, wherein the lean amine liquid inlet 222 is connected to the lean amine liquid outlet 211 of the solvent regeneration tower 210, and the second stripping steam outlet 223 is connected to the second gas phase return port 212 of the solvent regeneration tower 210. A first steam generator 130 and / or a second steam generator 230, wherein: the first hot-side inlet 131 of the first steam generator 130 is connected to the purified water outlet 111, the first cold-side inlet 132 of the first steam generator 130 is connected to the first condensate outlet 124, the second hot-side inlet 231 of the second steam generator 230 is connected to the lean amine liquid outlet 211, and the second cold-side inlet 232 of the second steam generator 230 is connected to the second condensate outlet 224; The vapor compression unit 300 has a vapor phase inlet 310 connected to the first gas outlet 133 of the first steam generator 130 and / or the second gas outlet 233 of the second steam generator 230, and a vapor phase outlet 320 connected to the first steam inlet 121 and the second steam inlet 221.

[0026] Wastewater stripping tower 110 is used to receive acidic water containing acidic components such as H2S, NH3, and CO2. It utilizes steam provided by wastewater stripping reboiler 120 as a heat source and stripping medium to remove the acidic components from the liquid phase to the gas phase, outputting purified water and acidic gas. Solvent regeneration tower 210 is used to receive amine-rich liquid and utilizes stripping steam provided by solvent reboiler 220 to regenerate the amine liquid.

[0027] The first steam generator 130 uses the purified water from the wastewater stripping tower 110 as a heat source and the high-temperature condensate discharged from the wastewater stripping reboiler 120 as a heat absorption medium. Through heat exchange between the partition walls, the temperature of the purified water is reduced, and the condensate absorbs heat and partially evaporates to produce low-pressure saturated steam, thus achieving dual recovery of the waste heat from the purified water in the wastewater stripping tower 110 and the waste heat from the condensate in the wastewater stripping reboiler 120.

[0028] The second steam generator 230 uses the lean amine liquid from the solvent regeneration tower 210 as a heat source and the high-temperature condensate discharged from the solvent reboiler 220 as a heat absorption medium. Through heat exchange between the partition walls, the temperature of the lean amine liquid is reduced, and the condensate absorbs heat and partially evaporates to produce low-pressure saturated steam, thus achieving dual recovery of the waste heat of the lean amine liquid in the solvent regeneration tower 210 and the waste heat of the condensate in the solvent reboiler 220.

[0029] The steam compression unit 300 adiabatically compresses and pressurizes the low-pressure saturated steam produced by the first steam generator 130, then directly sends it back to the wastewater stripping reboiler 120 as a heat source, forming a closed-loop recycling of waste heat and replacing part of the externally supplied high-quality steam. Alternatively, the steam compression unit 300 adiabatically compresses and pressurizes the low-pressure saturated steam produced by the second steam generator 230, then directly sends it back to the solvent reboiler 220 as a heat source, forming a closed-loop recycling of waste heat and replacing part of the externally supplied high-quality steam.

[0030] The wastewater stripping and solvent regeneration heat self-circulation system of this application, through the cooperation of wastewater stripping tower 110, wastewater stripping reboiler 120, solvent regeneration tower 210, solvent reboiler 220, first steam generator 130 and / or second steam generator 230, and steam compression unit 300, can achieve: Deep recovery of waste heat: The waste heat of the purified water in the wastewater stripping tower 110, the waste heat of the lean amine liquid in the solvent regeneration tower 210, and the waste heat of the condensate in the wastewater stripping reboiler 120 / solvent reboiler 220 are recovered in a dual manner and low-pressure steam is produced through the first steam generator 130 / second steam generator 230. Heat self-circulation: The self-generated steam from the first steam generator 130 / second steam generator 230 is compressed by the steam compression unit 300 and reused in the wastewater stripping reboiler 120 / solvent reboiler 220, replacing part of the externally supplied high-quality steam, realizing the closed-loop circulation of heat within the system and reducing the consumption of externally supplied steam. Energy saving and consumption reduction: According to experimental data, the wastewater stripping and solvent regeneration heat self-circulation system of this application can reduce fresh steam consumption by more than 30%, achieve a comprehensive energy saving rate of 31.7% to 33.8%, and reduce operating costs by more than 27%. Structural compatibility: The two sets of equipment, wastewater stripping tower 110 and solvent regeneration tower 210, can be independently configured with a first steam generator 130 / second steam generator 230 as needed, and share a set of steam compression unit 300, reducing investment costs.

[0031] In some embodiments, the wastewater stripping and solvent regeneration heat self-circulation system further includes a first condensate pump 410 and / or a second condensate pump 420, wherein: the first condensate pump 410 is connected between the first cold-side outlet 134 of the first steam generator 130 and the liquid phase inlet 330 of the steam compression unit 300, and the second condensate pump 420 is connected between the second cold-side outlet 234 of the second steam generator 230 and the liquid phase inlet 330 of the steam compression unit 300; and the outlets of the first condensate pump 410 and / or the second condensate pump 420 are also connected to a condensate outlet 810.

[0032] The first condensate pump 410 is used to pressurize and transport the low-temperature condensate (temperature, for example, 90°C to 105°C) after heat exchange in the first steam generator 130 to the steam compression unit 300 for use as desuperheating water. The second condensate pump 420 is used to pressurize and transport the low-temperature condensate after heat exchange in the second steam generator 230 to the steam compression unit 300 for use as desuperheating water. The first condensate pump 410 and / or the second condensate pump 420 can also split the pressurized condensate, with one part used as desuperheating water and the other part discharged to the condensate outlet 810, realizing two-stage utilization of condensate for desuperheating and discharge. The desuperheating water is used to control the exhaust temperature of the steam compression unit 300 (the flow rate of the desuperheating water branch accounts for, for example, 10% to 20%), and the discharged part (flow rate accounts for, for example, 80% to 90%) can be recovered to achieve full recovery of waste heat from the condensate. By spraying desuperheating water into the steam compression unit 300 (e.g., a steam compressor), the exhaust temperature during the adiabatic compression process is effectively controlled, preventing overheating and extending equipment life. When condensate is discharged from the wastewater stripping reboiler 120 or the solvent reboiler 220, its temperature is between 130°C and 150°C. After heat exchange in the first steam generator 130 or the second steam generator 230, the temperature is reduced to 90°C to 105°C. It is then further processed and exported, achieving cascaded utilization of heat.

[0033] In some embodiments, the wastewater stripping and solvent regeneration heat self-circulation system further includes a first liquid level regulating valve K1, which is connected in the pipeline from the first cold side outlet 134 to the first condensate pump 410, for controlling the cold side liquid level of the first steam generator 130, ensuring gas-liquid balance in the first steam generator 130, preventing dry burning or excessively high liquid level from affecting evaporation efficiency, and ensuring stable steam production.

[0034] In some embodiments, the wastewater stripping and solvent regeneration heat self-circulation system further includes a second liquid level regulating valve K2, which is connected in the pipeline from the second cold side outlet 234 to the second condensate pump 420, for controlling the cold side liquid level of the second steam generator 230, ensuring gas-liquid balance in the second steam generator 230, preventing dry burning or excessively high liquid level from affecting evaporation efficiency, and ensuring stable steam production.

[0035] In some embodiments, the wastewater stripping and solvent regeneration heat self-circulation system further includes a desuperheating water regulating valve K3, which is connected to the pipeline from the outlet of the first condensate pump 410 and / or the second condensate pump 420 to the liquid phase inlet 330. It is used to precisely regulate the flow rate of desuperheating water entering the vapor compression unit 300 and can be adjusted in real time according to the temperature feedback of the vapor phase outlet 320 to ensure that the exhaust temperature is controlled within a safe range.

[0036] In some embodiments, the wastewater stripping and solvent regeneration heat self-circulation system further includes: a first inlet / outlet heat exchanger 510, having a first heat exchange pipe 511 and a second heat exchange pipe 512, the first heat exchange pipe 511 and the second heat exchange pipe 512 being thermally coupled, the first heat exchange pipe 511 being connected between the first hot-side outlet 135 of the first steam generator 130 and the purified water outlet 820, and the second heat exchange pipe 512 being connected between the acidic water inlet 830 and the wastewater stripping tower 1. Between the acidic water inlet 113 of 10; the second inlet and outlet heat exchanger 520, having a third heat exchange pipe 521 and a fourth heat exchange pipe 522, the third heat exchange pipe 521 and the fourth heat exchange pipe 522 being thermally coupled, the third heat exchange pipe 521 being connected between the second hot side outlet 235 of the second steam generator 230 and the lean amine liquid outlet 840, and the fourth heat exchange pipe 522 being connected between the rich amine liquid outlet 850 and the rich amine liquid inlet 213 of the solvent regeneration tower 210.

[0037] The condensate outlet 810, purified water outlet 820, acidic water inlet 830, lean amine solution outlet 840, and rich amine solution inlet 850 refer to the connection interfaces with external systems (such as upstream units, downstream units, and the entire plant's piping network). Specifically, condensate outlet 810 sends out treated condensate, purified water outlet 820 sends out treated purified water, acidic water inlet 830 receives acidic water from upstream units, lean amine solution outlet 840 sends out regenerated lean amine solution, and rich amine solution inlet 850 receives rich amine solution from the upstream absorption tower.

[0038] The first heat exchange pipe 511 of the first feed heat exchanger 510 receives purified water (temperature reduced to 95°C to 110°C) after heat exchange with the first steam generator 130, and transfers its heat to the second heat exchange pipe 512. The second heat exchange pipe 512 of the first feed heat exchanger 510 receives acidic raw material water and performs indirect heat exchange with the purified water in the first heat exchange pipe 511 to preheat the acidic raw material water. The third heat exchange pipe 521 of the second feed heat exchanger 520 receives lean amine liquid (temperature reduced to 95°C to 110°C) after heat exchange with the second steam generator 230, and transfers its heat to the fourth heat exchange pipe 522. The fourth heat exchange pipe 522 of the second feed heat exchanger 520 receives rich amine raw material liquid and performs indirect heat exchange with the lean amine liquid in the third heat exchange pipe 521 to preheat the rich amine raw material liquid.

[0039] By utilizing the characteristic that the purified water output from the wastewater stripping tower 110 has been cooled (from 120℃ to 130℃, then to 95℃ to 110℃) by the first steam generator 130 before entering the first feed heat exchanger 510, a larger temperature difference is achieved during heat exchange between the purified water and the raw material, resulting in higher heat exchange efficiency. Similarly, by utilizing the characteristic that the lean amine solution output from the solvent regeneration tower 210 has been cooled (from 120℃ to 130℃, then to 95℃ to 110℃) by the second steam generator 230 before entering the second feed heat exchanger 520, a larger temperature difference is achieved during heat exchange between the lean amine solution and the raw material, resulting in higher heat exchange efficiency. According to experimental data, the temperature of the purified water decreases by approximately 5℃ after heat exchange, and the temperature of the lean amine solution decreases by approximately 5.1℃. Preheating the raw material through the first feed heat exchanger 510 and the second feed heat exchanger 520 can reduce the heat load on the wastewater stripping reboiler 120 and the solvent reboiler 220, thereby reducing steam consumption. The purified water output from the wastewater stripping tower 110 passes sequentially through the first inlet / outlet heat exchanger 510 (for heat exchange with condensate) and the first inlet / outlet heat exchanger 510 (for heat exchange with raw materials), achieving cascaded utilization of heat. The lean amine solution output from the solvent regeneration tower 210 passes sequentially through the second inlet / outlet heat exchanger 520 (for heat exchange with condensate) and the second inlet / outlet heat exchanger 520 (for heat exchange with raw materials), achieving cascaded utilization of heat.

[0040] In some embodiments, the wastewater stripping and solvent regeneration heat self-circulation system further includes: a first raw material preheating heat exchanger 610, having a fifth heat exchange pipe 611 and a sixth heat exchange pipe 612, the fifth heat exchange pipe 611 and the sixth heat exchange pipe 612 being thermally coupled, the fifth heat exchange pipe 611 being connected between the second heat exchange pipe 512 and the acidic water inlet 113, and the sixth heat exchange pipe 612 being connected between the first acidic gas outlet 114 and the first acidic gas outlet 860 of the wastewater stripping tower 110; a first reflux tank 620 and a first reflux pump 630 connected in series, wherein the first reflux tank 620 is connected to the sixth heat exchange pipe 612, the first reflux pump 630 is connected to the first reflux inlet 115 of the wastewater stripping tower 110, and the first reflux tank 620 is also connected to the first acidic gas outlet 860.

[0041] The fifth heat exchange pipe 611 of the first raw material preheating heat exchanger 610 receives the acidic raw material water preheated by the first inlet / outlet heat exchanger 510 and exchanges heat with the sixth heat exchange pipe 612. The sixth heat exchange pipe 612 of the first raw material preheating heat exchanger 610 receives acidic gas (approximately 105°C to 125°C) discharged from the wastewater stripping tower 110 and exchanges heat with the acidic raw material water in the fifth heat exchange pipe 611 through indirect wall heat exchange, further heating the raw material before sending it into the wastewater stripping tower 110. Through the first raw material preheating heat exchanger 610, the waste heat in the gas phase of the wastewater stripping tower 110 that was originally lost through direct air cooling or water cooling is recovered. Because the purified water output from the wastewater stripping tower 110 experiences a significant temperature drop after heat exchange in the first steam generator 130, the temperature of the raw material preheated in the first inlet / outlet heat exchanger 510 decreases. Through waste heat compensation in the gas phase of the wastewater stripping tower 110, the final inlet temperature of the raw material is maintained consistent with or slightly increased compared to the original process, ensuring stable gas phase load in the stripping section of the wastewater stripping tower 110. Furthermore, the heat exchange medium uses both the raw material (acidic water) and the overhead gas (containing acidic components such as H2S, NH3, and CO2), both of which are of the same composition and have strong process compatibility. Even if a slight leak occurs in the first raw material preheating heat exchanger 610, it will not affect the process parameters or operational stability, fundamentally solving the corrosion and leakage problems associated with waste heat recovery in the wastewater stripping tower 110.

[0042] The first reflux tank 620 is used for gas-liquid separation of the cooled gas-liquid mixture. The separated gas phase (high-purity acidic gas) is sent to the first acidic gas outlet 860 (such as a sulfur recovery unit), and the liquid phase is the reflux liquid (mainly ammonia-containing water). The reflux liquid is pressurized by the first reflux pump 630 and sent back to the wastewater stripping tower 110 as top reflux, which can absorb the heat at the top of the tower and maintain the stability of the gas phase composition at the top of the tower.

[0043] In some embodiments, the wastewater stripping and solvent regeneration heat self-circulation system further includes: a first cooling device 515, connected between the first heat exchange pipeline 511 and the purified water outlet 820, receiving the purified water after heat exchange by the first inlet and outlet heat exchanger 510, further cooling it to the outlet temperature (usually below 60°C) before sending it out of the system.

[0044] In some embodiments, the wastewater stripping and solvent regeneration heat self-circulation system further includes: a second cooling device 640, connected between the sixth heat exchange pipeline 612 and the first reflux tank 620, receiving the acidic gas (which has completed heat exchange with the raw material) after heat exchange by the first raw material preheating heat exchanger 610, and further cooling it to condense the condensable components in the acidic gas.

[0045] In some embodiments, the wastewater stripping and solvent regeneration heat self-circulation system further includes: a second raw material preheating heat exchanger 710, having a seventh heat exchange pipeline 711 and an eighth heat exchange pipeline 712, the seventh heat exchange pipeline 711 and the eighth heat exchange pipeline 712 being thermally coupled, the seventh heat exchange pipeline 711 being connected between the fourth heat exchange pipeline 522 and the amine-rich liquid external inlet 850, and the eighth heat exchange pipeline 712 being connected between the second acid gas outlet 214 and the second acid gas external outlet 870 of the solvent regeneration tower 210; a second reflux tank 720 and a second reflux pump 730 connected in series, wherein the second reflux tank 720 is connected to the eighth heat exchange pipeline 712, the second reflux pump 730 is connected to the second reflux inlet 215 of the solvent regeneration tower 210, and the second reflux tank 720 is also connected to the second acid gas external outlet 870.

[0046] The seventh heat exchange pipe 711 of the second raw material preheating heat exchanger 710 receives the ammonia-rich raw material preheated by the second inlet / outlet heat exchanger 520 and exchanges heat with the eighth heat exchange pipe 712. The eighth heat exchange pipe 712 of the second raw material preheating heat exchanger 710 receives acidic gas (approximately 95°C to 110°C) discharged from the solvent regeneration tower 210 and performs indirect heat exchange with the ammonia-rich raw material in the seventh heat exchange pipe 711, further heating the raw material before sending it into the solvent regeneration tower 210. Through the second raw material preheating heat exchanger 710, the waste heat in the gas phase of the solvent regeneration tower 210, which was originally lost through direct air cooling or water cooling, is recovered. Because the temperature drop of the lean ammonia liquid output from the solvent regeneration tower 210 increases after heat exchange in the second steam generator 230, the temperature of the raw material preheated in the second feed heat exchanger 520 decreases. Through gas-phase waste heat compensation in the solvent regeneration tower 210, the final feed temperature entering the tower is maintained consistent with or slightly increased compared to the original process, ensuring stable gas-phase load in the stripping section of the solvent regeneration tower 210. Furthermore, the heat exchange medium uses both the raw material (rich ammonia liquid) and the overhead gas (containing acidic components such as H2S, NH3, and CO2), both of which are of the same composition and have strong process compatibility. Even if a slight leak occurs in the second raw material preheating heat exchanger 710, it will not affect the process parameters or operational stability, fundamentally solving the corrosion and leakage problems associated with waste heat recovery in the solvent regeneration tower 210.

[0047] The second reflux tank 720 is used for gas-liquid separation of the cooled gas-liquid mixture. The separated gas phase (high-purity H2S / CO2 acidic gas) is sent to the second acidic gas outlet 870 (such as a sulfur recovery unit), while the liquid phase is the reflux liquid, whose main components are condensate and a small amount of entrained amine liquid. After being pressurized by the second reflux pump 730, it is sent back to the solvent regeneration tower 210 as top reflux, which can absorb the heat at the top of the tower and maintain the stability of the composition of the gas phase at the top of the tower.

[0048] In some embodiments, the wastewater stripping and solvent regeneration heat self-circulation system further includes: a third cooling device 525, connected between the third heat exchange pipeline 521 and the lean amine liquid outlet 840, receiving the lean amine liquid after heat exchange by the second inlet and outlet heat exchanger 520, further cooling it to the outlet temperature before sending it out of the system.

[0049] In some embodiments, the wastewater stripping and solvent regeneration heat self-circulation system further includes: a fourth cooling device 740, connected between the eighth heat exchange pipeline 712 and the second reflux tank 720, receiving the acidic gas after heat exchange by the second raw material preheating heat exchanger 710, and further cooling it to condense the condensable components in the acidic gas.

[0050] By utilizing the aforementioned first cooling device 515, second cooling device 640, third cooling device 525, and fourth cooling device 740, the following beneficial effects can be achieved: Meeting export requirements: After multiple heat exchanges within the system, the temperature of purified water and lean amine solution may still exceed the export requirements. Cooling devices lower these temperatures to a safe level before export. Targeted heat utilization: The cooling devices are located at the end of the heat exchange process, ensuring that heat is preferentially used for raw material preheating and steam generation. Only low-grade heat that cannot be ultimately utilized is dissipated through cooling, conforming to the energy-saving principles of temperature matching and tiered utilization. Protecting downstream equipment: Reducing the temperature of the exported medium avoids thermal shock or damage to downstream equipment.

[0051] Furthermore, in some embodiments, the wastewater stripping and solvent regeneration heat self-circulation system also includes a first condensate control valve K4, connected in the pipeline from the first condensate outlet 124 to the first cold side inlet 132, for controlling the flow rate of condensate from the wastewater stripping reboiler 120 into the first steam generator 130 and adjusting the steam production.

[0052] In some embodiments, the wastewater stripping and solvent regeneration heat self-circulation system further includes a second condensate control valve K5, connected in the pipeline from the second condensate outlet 224 to the second cold side inlet 232, for controlling the flow rate of condensate from the solvent reboiler 220 into the second steam generator 230 and adjusting the steam production.

[0053] In some embodiments, the wastewater stripping and solvent regeneration heat self-circulation system further includes a first flow regulating valve K6, connected in the pipeline between the external steam inlet 880 and the first steam inlet 121, for controlling the flow rate of external supplementary steam entering the wastewater stripping reboiler 120, which can supplement heat when the system starts up or when the self-generated steam is insufficient. The external steam inlet 880 can be connected to an interface of an external fresh steam network (such as a plant-wide steam system).

[0054] In some embodiments, the wastewater stripping and solvent regeneration heat self-circulation system further includes a second flow regulating valve K7, which is connected in the pipeline between the external steam inlet 880 and the second steam inlet 221, for controlling the flow rate of external supplementary steam entering the solvent reboiler 220, and can supplement heat when the system starts up or when the self-generated steam is insufficient.

[0055] In some embodiments, the wastewater stripping and solvent regeneration heat self-circulation system further includes a third flow regulating valve K8, which is connected in the pipeline between the gas phase outlet 320 and the first steam inlet 121, for controlling the flow rate of self-generated circulating steam entering the wastewater stripping reboiler 120.

[0056] In some embodiments, the wastewater stripping and solvent regeneration heat self-circulation system further includes a fourth flow regulating valve K9, which is connected in the pipeline between the gas phase outlet 320 and the second steam inlet 221, for controlling the flow rate of self-generated circulating steam entering the solvent reboiler 220.

[0057] In the above embodiments, the first acidic gas outlet 114 is located at the top of the wastewater stripping tower 110, and the purified water outlet 111 is located at the bottom of the wastewater stripping tower 110. The operating temperature at the top of the wastewater stripping tower 110 is in the range of 105°C to 125°C, typically 15°C; the operating pressure at the top of the wastewater stripping tower 110 is in the range of 0.1 MPag to 0.2 MPag, typically 0.12 MPag. The operating temperature at the bottom of the wastewater stripping tower 110 is in the range of 120°C to 135°C, typically 125°C; the operating pressure at the bottom of the wastewater stripping tower 110 is in the range of 0.12 MPag to 0.25 MPag, typically 0.15 MPag. These parameter ranges are typical operating ranges for the wastewater stripping tower 110, ensuring effective separation of acidic components (H2S, NH3). Under these conditions, the gas phase at the top of the tower has a sufficiently high temperature (105°C to 125°C) for preheating the feedstock, and the material at the bottom of the tower has a sufficiently high temperature (120°C to 135°C) for exchanging heat with the condensate to produce steam.

[0058] In the above embodiments, the second acid gas outlet 214 is located at the top of the solvent regeneration tower 210, and the lean amine liquid outlet 211 is located at the bottom of the solvent regeneration tower 210. The operating temperature at the top of the solvent regeneration tower 210 is in the range of 95°C to 110°C, typically 105°C; the operating pressure at the top of the solvent regeneration tower 210 is in the range of 0.05 MPag to 0.15 MPa, typically 0.075 MPa. The operating temperature at the bottom of the solvent regeneration tower 210 is in the range of 115°C to 130°C, typically 120°C; the operating pressure at the bottom of the solvent regeneration tower 210 is in the range of 0.07 MPag to 0.2 MPa, typically 0.1 MPa. These parameter ranges are typical operating ranges for the solvent regeneration tower 210, ensuring effective removal of acidic components from the rich amine liquid. Under these conditions, the gas phase temperature at the top of the tower (95°C to 110°C) is used to preheat the rich amine liquid, and the lean amine liquid temperature at the bottom of the tower (115°C to 130°C) can be used to exchange heat with condensate to produce steam.

[0059] In the above embodiments, the condensate temperature output from the wastewater stripping reboiler 120 and the solvent reboiler 220 is in the range of 130°C to 150°C, typically 140°C. The high-temperature condensate is the main heat-absorbing medium in the wastewater stripping and solvent regeneration heat self-circulation system, and its high-grade waste heat is recovered and utilized through a steam generator. The condensate enters the cold side of the steam generator within this temperature range, expands to 90°C to 105°C after depressurization, and partially evaporates after heat exchange with the bottom material (120°C to 130°C), thus achieving waste heat recovery.

[0060] In the above embodiments, the steam generation temperature of the first steam generator 130 and / or the second steam generator 230 is in the range of 90°C to 105°C, typically 100°C. The low-pressure saturated steam in this temperature range, after being pressurized by the steam compression unit 300 (130°C to 160°C), can meet the heat source requirements of the reboiler.

[0061] In summary, the wastewater stripping and solvent regeneration heat self-circulation system of this application achieves deep recovery and recycling of waste heat throughout the entire process through the coordinated design of modules such as bottom waste heat recycling for steam generation, top waste heat preheating of raw materials, centralized steam compression, and condensate stage utilization. Under the premise of ensuring qualified process indicators and safe and stable operation, it significantly reduces the consumption of high-quality steam in the bottom reboiler.

[0062] Specifically, this application adds a high-efficiency first steam generator 130 and a second steam generator 230 between the bottom material outlet and the feed heat exchanger of the wastewater stripping tower 110 and the solvent regeneration tower 210, forming a bottom waste heat recycling steam generation unit. The core process logic of the bottom waste heat recycling steam generation unit is as follows: using the high-temperature condensate of about 140°C discharged from the bottom reboilers (wastewater stripping reboiler 120 and solvent reboiler 220) as the heat absorption medium, the condensate is depressurized and expanded to 90°C to 105°C through the first condensate control valve K4 and the second condensate control valve K5, and then introduced into the first steam generator 130 and the second steam generator 230 to conduct indirect heat exchange with the high-temperature purified water / lean amine liquid discharged from the bottom of the wastewater stripping tower 110 and the solvent regeneration tower 210. During the heat exchange process, the temperature of the high-temperature material at the bottom of the tower drops to 95°C to 110°C and is then fed into the first inlet / outlet heat exchanger 510 and the second inlet / outlet heat exchanger 520. The high-temperature condensate absorbs the waste heat of the material at the bottom of the tower and partially evaporates to produce saturated steam at 90°C to 105°C. At the same time, the temperature of the condensate drops to 90°C to 105°C, achieving a dual deep recovery of the waste heat of the material at the bottom of the tower and the waste heat of the steam condensate.

[0063] This application uses a steam compressor as a centralized steam compression unit 300. The wastewater stripping unit and the solvent regeneration unit can share a single steam compressor, realizing centralized pressurization of steam generated by multiple units. The core process logic of the centralized steam compression unit is as follows: the low-pressure saturated steam produced by the first steam generator 130 and the second steam generator 230 is sent to the steam compressor. After adiabatic compression and temperature and pressure increase to saturated steam of 130°C to 160°C, it is directly sent to the wastewater stripping reboiler 120 and the solvent reboiler 220 as a heat source, replacing part of the fresh high-quality steam and realizing closed-loop recycling of waste heat.

[0064] This application forms a condensate grading and utilization unit through a first condensate pump 410 and a second condensate pump 420. Its core process logic is as follows: the low-temperature condensate after heat exchange between the first steam generator 130 and the second steam generator 230 is pressurized by the first condensate pump 410 and the second condensate pump 420. Part of it is used as spray desuperheating water for the steam compressor to control the compressor exhaust temperature to stabilize, and the other part is transported to the plant's condensate pipeline network to realize the graded and full utilization of condensate.

[0065] Furthermore, this application utilizes a first raw material preheating heat exchanger 610 and a second raw material preheating heat exchanger 710 to form a raw material preheating unit using waste heat from the top of the tower. The core process logic is as follows: Addressing the issue of increased temperature drop in the bottom material after steam generation, leading to a decrease in the feed temperature after heat exchange in the feed and discharge heat exchangers, the raw material, after heat exchange in the first feed and discharge heat exchanger 510 / second feed and discharge heat exchanger 520, is fed into the first raw material preheating heat exchanger 610 / second raw material preheating heat exchanger 710 for deep heat exchange with the top gas phase. This recovers the waste heat from the top gas, raising the raw material temperature and ensuring that the final feed temperature remains consistent with or slightly higher than the original process. This guarantees stable gas phase load in the stripping section of the tower and prevents a decrease in stripping separation efficiency. Simultaneously, the heat exchange medium uses both the raw material and the top gas, which share the same composition and have strong process compatibility. Even if a slight leak occurs in the heat exchanger, it will not affect the process parameters or operational stability, thus mitigating the risk of corrosion and leakage from the top waste heat recovery process at the source.

[0066] To facilitate understanding of this application, examples are provided below. Those skilled in the art should understand that these examples are merely illustrative and should not be construed as limiting the scope of this application.

[0067] Case 1: The wastewater stripping treatment capacity is 125t / h, the solvent regeneration treatment capacity is 105.4t / h, and the annual operating time is 8000h; energy prices: steam price is 150 yuan / t, electricity price is 0.6 yuan / kW; energy consumption conversion factor: 0.3MPag to 0.4MPag; steam: 66, electricity: 0.21.

[0068] Table 1 - Changes before and after optimization in Case 1: project unit status quo This application Difference Wastewater stripping feed rate t / h 125 125 0 Wastewater stripping feed temperature ℃ 93.3 93.3 0 Wastewater stripping tower bottom purified water temperature ℃ 124 124 0 Temperature of purified water after heat exchange at the bottom of the wastewater stripping tower ℃ 67.2 62.2 5 Waste heat recovery from the top of the wastewater stripping tower kW 0 2800 -2800 Wastewater stripping tower bottom steam consumption t / h 18.3 18.3 0 Condensate outlet temperature ℃ 140 95 45 Solvent regeneration tower rich liquid feed rate t / h 105.4 105.4 0 Solvent regeneration tower rich liquid inlet temperature ℃ 96.5 94.3 2.2 Solvent regeneration tower bottom lean solution temperature ℃ 119.3 119.4 -0.1 Temperature of lean solution at the bottom of solvent regeneration tower after heat exchange ℃ 66.1 61 5.1 Solvent regeneration tower top heat recovery kW 0 1550 -1550 Solvent regeneration tower bottom steam consumption t / h 8.5 8.5 0 Condensate outlet temperature ℃ 135 95 40 Steam production from heat self-circulation t / h 0 12.8 -12.8 Increased power consumption kW 0 1350 -1350 Reduce energy consumption (equivalent to standard coal). t standard coal / a 20215 13800 6415 Energy efficiency % 0 31.7 -31.7 Steam saving rate % 0 47.8 -47.8 Operating costs Yuan / h 4020 2910.0 1110 Cost reduction rate % 0 27.6 -27.6 As shown in Case 1, after the implementation of this application, the temperature of the wastewater purified by stripping and heat exchange decreases by approximately 5°C, and the condensate outlet temperature drops from 140°C to 95°C, recovering approximately 2800kW of waste heat from the top of the tower; the temperature of the solvent regeneration lean solvent decreases by approximately 5.1°C after heat exchange, and the condensate outlet temperature drops from 135°C to 95°C, recovering approximately 1550kW of waste heat from the top of the tower; the self-circulating steam production is approximately 12.8t / h, the additional power consumption is approximately 1350kW, and the energy consumption (converted to standard coal equivalent) decreases from 20215t / a to 13800t / a, a reduction of 6415t / a, with an energy saving rate of approximately 31.7%; the operating cost decreases from 4020 yuan / h to 2910 yuan / h, a reduction of 1110 yuan / h, with an operating cost reduction rate of 27.6%, and an annual benefit of approximately 8.88 million yuan, demonstrating significant energy-saving benefits.

[0069] Case 2: The wastewater stripping treatment capacity is 80t / h, the solvent regeneration treatment capacity is 200t / h, and the annual operating time is 8400h; energy prices: steam price is 160 yuan / t, electricity price is 0.7 yuan / kW; energy consumption conversion factor: 0.3MPag to 0.4MPag; steam: 66, electricity: 0.21.

[0070] Table 2 - Changes before and after optimization in Case 2: project unit status quo This application Difference Wastewater stripping feed rate t / h 80 80 0 Wastewater stripping feed temperature ℃ 95.2 95.2 0 Temperature of lean liquor at the bottom of wastewater stripping tower ℃ 123.6 123.6 0 Temperature of lean liquor at the bottom of the wastewater stripping tower after heat exchange ℃ 66.4 62.5 3.9 Wastewater stripping tower top heat recovery kW 0 1960 -1960 Wastewater stripping tower bottom steam consumption t / h 11.7 11.7 0 Condensate outlet temperature ℃ 140 95 45 Solvent regeneration tower rich liquid feed rate t / h 200 200 0 Solvent regeneration tower rich liquid inlet temperature ℃ 95.4 95.4 0 Solvent regeneration tower bottom lean solution temperature ℃ 119.5 119.5 0 Temperature of lean solution at the bottom of solvent regeneration tower after heat exchange ℃ 64.2 60.8 3.4 Solvent regeneration tower top heat recovery kW 0 3300 -3300 Solvent regeneration tower bottom steam consumption t / h 14.9 14.9 0 Condensate outlet temperature ℃ 135 95 40 Steam production from heat self-circulation t / h 0 13.5 -13.5 Increased power consumption kW 0 1420 -1420 Reduce energy consumption (equivalent to standard coal). t standard coal / a 21067 13954 7114 Energy efficiency % 0 33.8 -33.8 Steam saving rate % 0 50.8 -50.8 Operating costs Yuan / h 4256 3090.0 1166 Cost reduction rate % 0 27.4 -27.4 As shown in Case 2, after the implementation of this application, the temperature of the wastewater purified by stripping and heat exchange decreased by approximately 3.9℃, and the condensate outlet temperature decreased from 140℃ to 95℃, recovering approximately 1960kW of waste heat from the top of the tower; the temperature of the lean solvent after solvent regeneration decreased by approximately 3.4℃, and the condensate outlet temperature decreased from 135℃ to 95℃, recovering approximately 3300kW of waste heat from the top of the tower; the self-circulating steam production was approximately 13.5t / h; the additional power consumption was approximately 1420kW; and the energy consumption (converted to standard coal equivalent) decreased from 21067t / a to 13954t / a, a reduction of 7114t / a, with an energy saving rate of approximately 33.8%; the operating cost decreased from 4256 yuan / h to 3090 yuan / h, a reduction of 1166 yuan / h, with an operating cost reduction rate of 27.4%, resulting in an annual benefit of approximately 9.794 million yuan, demonstrating significant energy-saving benefits.

[0071] Finally, it should be noted that the above description, in conjunction with specific preferred embodiments, provides a further detailed explanation of this application and should not be construed as limiting the specific implementation of this application to these descriptions. For those skilled in the art, various simple deductions or substitutions can be made without departing from the concept of this application, and all such modifications or substitutions should be considered within the scope of protection of this application.

Claims

1. A wastewater stripping and solvent regeneration heat self-circulation system, characterized in that, include: The wastewater stripping tower is configured to receive acidic water, remove acidic components through stripping steam, and output purified water and acidic gas. The wastewater stripping reboiler has a first steam inlet, a purified water inlet, a first stripping steam outlet, and a first condensate outlet. The purified water inlet is connected to the purified water outlet of the wastewater stripping tower, and the first stripping steam outlet is connected to the first gas phase return port of the wastewater stripping tower. The solvent regeneration tower is configured to receive amine-rich liquid, regenerate it using stripping steam, and output lean amine liquid and acidic gas. The solvent reboiler has a second steam inlet, a lean amine liquid inlet, a second stripping steam outlet, and a second condensate outlet. The lean amine liquid inlet is connected to the lean amine liquid outlet of the solvent regeneration tower, and the second stripping steam outlet is connected to the second gas phase return port of the solvent regeneration tower. A first steam generator and / or a second steam generator, wherein: the first hot-side inlet of the first steam generator is connected to the purified water outlet, the first cold-side inlet of the first steam generator is connected to the first condensate outlet, the second hot-side inlet of the second steam generator is connected to the lean amine liquid outlet, and the second cold-side inlet of the second steam generator is connected to the second condensate outlet. A vapor compression unit, wherein the vapor phase inlet of the vapor compression unit is connected to the first gas outlet of the first steam generator and / or the second gas outlet of the second steam generator, and the vapor phase outlet of the vapor compression unit is connected to the first steam inlet and the second steam inlet.

2. The system as described in claim 1, characterized in that, The system further includes a first condensate pump and / or a second condensate pump, wherein: The first condensate pump is connected between the first cold-side outlet of the first steam generator and the liquid-phase inlet of the steam compression unit, and the second condensate pump is connected between the second cold-side outlet of the second steam generator and the liquid-phase inlet of the steam compression unit. Furthermore, the outlets of the first condensate pump and / or the second condensate pump are also connected to the external condensate outlet.

3. The system as described in claim 2, characterized in that, The system also includes: A first liquid level regulating valve is connected in the pipeline from the first cold side outlet to the first condensate pump; and / or A second liquid level regulating valve is connected in the pipeline from the second cold side outlet to the second condensate pump; and / or A desuperheating water regulating valve is connected to the pipeline from the outlet of the first condensate pump and / or the second condensate pump to the liquid phase inlet.

4. The system as described in claim 1, characterized in that, The system also includes: The first inlet and outlet heat exchanger has a first heat exchange pipeline and a second heat exchange pipeline. The first heat exchange pipeline is thermally coupled to the second heat exchange pipeline. The first heat exchange pipeline is connected between the first hot side outlet of the first steam generator and the purified water outlet. The second heat exchange pipeline is connected between the acidic water inlet and the acidic water inlet of the wastewater stripping tower. The second inlet and outlet heat exchanger has a third heat exchange pipeline and a fourth heat exchange pipeline. The third heat exchange pipeline is thermally coupled to the fourth heat exchange pipeline. The third heat exchange pipeline is connected between the second hot side outlet of the second steam generator and the lean amine liquid outlet. The fourth heat exchange pipeline is connected between the rich amine liquid inlet and the rich amine liquid inlet of the solvent regeneration tower.

5. The system as described in claim 4, characterized in that, The system also includes: The first raw material preheating heat exchanger has a fifth heat exchange pipeline and a sixth heat exchange pipeline. The fifth heat exchange pipeline and the sixth heat exchange pipeline are thermally coupled. The fifth heat exchange pipeline is connected between the second heat exchange pipeline and the acidic water inlet. The sixth heat exchange pipeline is connected between the first acidic gas outlet and the first acidic gas external outlet of the wastewater stripping tower. A first reflux tank and a first reflux pump are connected in series, wherein the first reflux tank is connected to the sixth heat exchange pipeline, the first reflux pump is connected to the first reflux inlet of the wastewater stripping tower, and the first reflux tank is also connected to the first acid gas outlet.

6. The system as described in claim 5, characterized in that, The system also includes: A first cooling device is connected between the first heat exchange pipeline and the purified water outlet; and / or The second cooling device is connected between the sixth heat exchange pipeline and the first reflux tank.

7. The system as described in claim 4, characterized in that, The system also includes: The second raw material preheating heat exchanger has a seventh heat exchange pipeline and an eighth heat exchange pipeline. The seventh heat exchange pipeline and the eighth heat exchange pipeline are thermally coupled. The seventh heat exchange pipeline is connected between the fourth heat exchange pipeline and the rich amine liquid inlet. The eighth heat exchange pipeline is connected between the second acid gas outlet and the second acid gas external outlet of the solvent regeneration tower. A second reflux tank and a second reflux pump are connected in series, wherein the second reflux tank is connected to the eighth heat exchange pipeline, the second reflux pump is connected to the second reflux inlet of the solvent regeneration tower, and the second reflux tank is also connected to the second acid gas outlet.

8. The system as described in claim 7, characterized in that, The system also includes: A third cooling device is connected between the third heat exchange pipeline and the outlet of the lean amine solution; and / or The fourth cooling device is connected between the eighth heat exchange pipeline and the second reflux tank.

9. The system as claimed in claim 1, characterized in that, The system also includes: A first condensate control valve is connected in the pipeline from the first condensate outlet to the first cold-side inlet; and / or A second condensate control valve is connected in the pipeline from the second condensate outlet to the second cold-side inlet; and / or A first flow regulating valve is connected in the pipeline between the external steam inlet and the first steam inlet; and / or A second flow regulating valve is connected in the pipeline between the external steam inlet and the second steam inlet; and / or A third flow regulating valve is connected in the pipeline between the gas phase outlet and the first steam inlet; and / or A fourth flow regulating valve is connected in the pipeline between the gas phase outlet and the second steam inlet.

10. The system as described in claim 1 or 5, characterized in that, The first acidic gas outlet is located at the top of the wastewater stripping tower, and the purified water outlet is located at the bottom of the wastewater stripping tower; the operating temperature at the top of the wastewater stripping tower is in the range of 105°C to 125°C, and the operating pressure at the top of the wastewater stripping tower is in the range of 0.1 MPa g to 0.2 MPa g; the operating temperature at the bottom of the wastewater stripping tower is in the range of 120°C to 135°C, and the operating pressure at the bottom of the wastewater stripping tower is in the range of 0.12 MPa g to 0.25 MPa g; and / or The second acidic gas outlet is located at the top of the solvent regeneration tower, and the lean amine liquid outlet is located at the bottom of the solvent regeneration tower; the operating temperature at the top of the solvent regeneration tower is in the range of 95°C to 110°C, and the operating pressure at the top of the solvent regeneration tower is in the range of 0.05 MPa to 0.15 MPa; the operating temperature at the bottom of the solvent regeneration tower is in the range of 115°C to 130°C, and the operating pressure at the bottom of the solvent regeneration tower is in the range of 0.07 MPa to 0.2 MPa; and / or The condensate temperature output from the wastewater stripping reboiler and the solvent reboiler is in the range of 130°C to 150°C; and / or The steam generation temperature of the first steam generator and / or the second steam generator is in the range of 90°C to 105°C.

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