An acid gas purification system based on a dual high-speed permanent magnet explosion-proof centrifugal compressor

Abstract

This invention discloses an acid gas purification system based on dual high-speed permanent magnet explosion-proof centrifugal compressors, comprising an absorption purification system, an energy-saving flash evaporation system, and a heat pump distillation regeneration system. The flash tank of the energy-saving flash evaporation system is connected to a #1 demister; the outlet of the #1 demister is connected to the inlet pipe of the #1 high-speed permanent magnet explosion-proof centrifugal compressor, and the outlet pipe of the #1 high-speed permanent magnet explosion-proof centrifugal compressor is connected to the hot-side inlet pipe of the flash evaporator heat exchanger. The feed pipe at the top of the distillation column of the heat pump distillation regeneration system is connected to the cold-side outlet pipe of the bottom liquid heat exchanger; the distillation column is connected to a #2 demister; the outlet pipe of the #2 demister is connected to the inlet pipe of the #2 high-speed permanent magnet explosion-proof centrifugal compressor, and the outlet pipe of the #2 high-speed permanent magnet explosion-proof centrifugal compressor is connected to the shell inlet pipe of the reboiler. This invention fully utilizes the energy of the acid gas purification process, greatly improving the heat utilization rate of flash vapor, distillation column top gas phase, and bottom liquid, resulting in significant energy saving and consumption reduction.

Description

Technical Field

[0001] This invention relates to the field of natural gas and oil refinery acid gas desulfurization and decarbonization technology, and in particular to an energy-saving purification system for the entire process of natural gas and oil refinery desulfurization and decarbonization. Background Technology

[0002] The desulfurization and decarbonization processes for natural gas and oil refineries have a long history. In the 1930s, absorption processes using amine solutions as absorbents were the mainstream technology. To date, the desulfurization and decarbonization processes and methods for natural gas and oil refineries have become increasingly sophisticated.

[0003] Existing technologies primarily utilize alkaline solvents to chemically react with acidic components such as H2S, CO2, and organic sulfur compounds in acidic gases, forming specific compounds that capture these acidic substances, thereby purifying the acidic gases. This chemical reaction is reversible; under conditions of increased temperature and decreased pressure, the formed compounds decompose, releasing the captured acidic gases, and allowing the alkaline solvent to be regenerated and recycled. Specifically, existing amine-based desulfurization processes, such as... Figure 1 As shown: Raw material gas S1 (mainly derived from dry gas and sulfur-containing natural gas produced during the refining process of sulfur-containing petroleum, its main components, besides H2S, also include H2, CO2, CH4, C2, C3, C4, and C5 gases) enters absorption tower B1 from the bottom, flowing upwards. The ambient temperature absorbent liquid stream S14 (lean liquid) enters from the top of absorption tower B1, flowing downwards. The gaseous and absorbent liquid streams come into countercurrent contact. Acidic components such as H2S or CO2 are absorbed by the absorbent during this process, forming rich liquid S2 at the bottom of the tower. The purified gas S15 enters the next process. Rich liquid S2 is collected from the bottom of absorption tower B1 and depressurized by pressure reducing valve B4 to form stream S3, which enters flash tank B3. Light components such as dissolved and entrained hydrocarbons S4 in rich liquid S2 are flashed out and collected for the next process. The rich liquid S5 from the bottom of flash tank B3 is pumped into the lean-rich liquid heat exchange system B5. After preheating, it forms stream S7, which then enters distillation column B2 for separation. Acidic gases are drawn from the top of distillation column B2 and enter the condenser, finally reaching the reflux tank. After passing through the reflux pump, high-concentration acidic substances such as H2S or CO2 are collected as product S9 for the next process. The lean liquid S8 from the bottom of the distillation column enters the lean-rich liquid heat exchange system B5 for cooling, forming stream S6. Stream S6 enters the lean liquid replenishment system B8, where it mixes with replenished water S10 and replenished amine liquid S11 to form stream S12. Stream S12 is pumped by feed pump B6 to form stream S13. Stream S13 is conveyed through the circulating water cooler B7 to form stream S14, which is then recycled back to the top of the absorber. Figure 1Existing desulfurization and decarbonization technologies, exemplified by [example technology name], require traditional distillation processes, resulting in significant energy consumption. This energy consumption primarily originates from three sources: steam consumption, cooling water consumption, and electricity consumption. According to relevant literature, steam consumption accounts for 73.26%, cooling water consumption accounts for 20.30%, and electricity consumption accounts for 6.44%. Summary of the Invention

[0004] To overcome the high energy consumption problem of the existing technology, the present invention provides an acid gas purification system based on a dual high-speed permanent magnet explosion-proof centrifugal compressor, which significantly reduces the consumption of external steam, greatly improves the energy utilization efficiency of the system, significantly reduces the system energy consumption, and has high purification efficiency.

[0005] To achieve the objectives of this invention, the technical solution adopted is as follows:

[0006] An acid gas purification system based on a dual high-speed permanent magnet explosion-proof centrifugal compressor includes an absorption purification system, an energy-saving flash evaporation system, and a heat pump distillation regeneration system. The absorption purification system includes a purifying agent storage tank, a fan, and a purification tower. The inlet of the purifying agent storage tank is connected to the purifying agent feed pipe, the outlet of the purifying agent storage tank is connected to the purification tower, and the air inlet of the purification tower is connected to the fan. The circulation pipe of the purification tower is connected to the outlet pipe of the reflux pump, the inlet pipe of the reflux pump is connected to the circulation outlet pipe of the purification tower and connected to the hot side outlet pipe of the circulating water cooler, and the outlet of the purification tower is connected to the flash tank.

[0007] The energy-saving flash evaporation system includes: a flash recovery tank, a No. 1 high-speed permanent magnet explosion-proof centrifugal compressor, a No. 1 demister, a flash tank, and a flash heat exchanger; the flash tank is connected to the No. 1 demister; the outlet of the No. 1 demister is connected to the inlet pipe of the No. 1 high-speed permanent magnet explosion-proof centrifugal compressor, the outlet pipe of the No. 1 high-speed permanent magnet explosion-proof centrifugal compressor is connected to the hot side inlet pipe of the flash heat exchanger, the hot side outlet pipe of the flash heat exchanger is connected to the liquid inlet of the flash recovery tank; the cold side of the flash heat exchanger is connected to the outlet of the flash tank.

[0008] The heat pump distillation regeneration system includes a distillation column, a distillation recovery tank, a reboiler, a circulating water cooler, a column bottom liquid heat exchanger, a No. 2 demister, and a No. 2 high-speed permanent magnet explosion-proof centrifugal compressor; the cold-side outlet of the flash evaporator heat exchanger is connected to the cold-side inlet of the column bottom liquid heat exchanger; the hot-side inlet pipe of the column bottom liquid heat exchanger is connected to the lower part of the distillation column; the hot-side outlet pipe of the column bottom liquid heat exchanger is connected to the hot-side inlet pipe of the circulating water cooler; the hot-side outlet pipe of the circulating water cooler is connected to the outlet pipe of the reflux pump; and the upper feed pipe of the distillation column... The distillation column is connected to the cold-side outlet pipe of the bottom liquid heat exchanger, the distillation column is connected to the No. 2 demister, the No. 2 demister outlet pipe is connected to the No. 2 high-speed permanent magnet explosion-proof centrifugal compressor inlet pipe, the No. 2 high-speed permanent magnet explosion-proof centrifugal compressor outlet pipe is connected to the reboiler shell inlet pipe; the reboiler shell outlet is connected to the distillation recovery tank; the distillation recovery tank outlet is connected to the distillation column reflux pipe, the reboiler tube inlet pipe is connected to the distillation column circulation outlet pipe, and the reboiler tube outlet pipe is connected to the distillation column circulation feed inlet.

[0009] To further achieve the purpose of this invention, preferably, the blower is connected to external natural gas and oil refinery pipelines containing sulfur, hydrogen sulfide, and carbon dioxide; the purified gas outlet pipe of the purification tower is connected to an external purified gas connection pipe.

[0010] Preferably, the outlet flange of the purifying agent storage tank is connected to the inlet pipe of the purifying agent delivery pump, and the outlet pipe of the purifying agent delivery pump is connected to the flange of the purifying agent inlet pipe of the purification tower.

[0011] Preferably, the discharge port flange of the purification tower is connected to the inlet pipe of the discharge pump, and the outlet pipe of the discharge pump is connected to the inlet of the flash tank.

[0012] Preferably, the cold side interface of the flash evaporator heat exchanger is connected to the outlet pipe of the transfer pump; the inlet pipe of the transfer pump is connected to the outlet of the flash tank.

[0013] Preferably, the hot-side inlet pipe of the bottom liquid heat exchanger is connected to the outlet pipe of the bottom liquid discharge pump, and the inlet pipe of the bottom liquid discharge pump is connected to the lower part of the distillation column.

[0014] Preferably, the inlet pipe of the reboiler tube layer is connected to the outlet of the reboiler circulating pump, and the inlet of the reboiler circulating pump is connected to the circulating outlet pipe of the distillation column.

[0015] Preferably, the liquid outlet of the distillation recovery tank is connected to the inlet pipe of the distillation column reflux pump; the discharge outlet pipe of the distillation column reflux pump is connected to the distillation column reflux pipe.

[0016] Preferably, a branch pipe is provided on the pipeline connecting the outlet pipe of the distillation column reflux pump to the reflux pipe of the distillation column.

[0017] Preferably, the inlet and outlet of the cold side of the circulating water cooler are connected to the external circulating cooling water inlet pipe and outlet pipe, respectively.

[0018] Compared with the prior art, the present invention has the following advantages:

[0019] 1) In this invention, the acid gas (containing sulfur, hydrogen sulfide, carbon dioxide, etc.) is purified by an absorption and purification system to obtain a rich liquid, which then enters a flash tank for flash separation. The flash vapor generated by the energy-saving flash system is then compressed by a No. 1 high-speed permanent magnet explosion-proof centrifugal compressor, increasing the temperature, pressure, and enthalpy of the low-grade flash vapor. The compressed, high-enthalpy gas phase then undergoes thorough heat exchange with the flash-separated rich liquid. This not only achieves flash vapor separation but also further increases the temperature of the rich liquid, reducing steam consumption in the distillation process.

[0020] 2) In this invention, the gas phase at the top of the heat pump distillation regeneration system is recompressed by the No. 2 high-speed permanent magnet explosion-proof centrifugal compressor and then enters the reboiler to fully exchange heat with the bottom liquid, which replenishes the heat of the circulating liquid in the reboiler, thereby reducing the consumption of external steam, greatly improving the energy utilization efficiency of the system, and also saving operating investment.

[0021] 3) Both the No. 1 and No. 2 high-speed permanent magnet explosion-proof centrifugal compressors in this invention adopt high-speed permanent magnet explosion-proof centrifugal compressors with an efficiency of over 95.5%. Compared with traditional positive displacement compressors and centrifugal gearbox compressors, they have advantages such as higher energy conversion efficiency, more compact and simple structure, wider operating range, convenient maintenance, low noise, and high reliability. This further reduces the energy consumption of the acid gas absorption and purification system, and also reduces the system's maintenance costs. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the existing technology for acid gas purification.

[0023] Figure 2 This is a schematic diagram of the structure of an acid gas purification system based on dual high-speed permanent magnet explosion-proof centrifugal compression according to the present invention.

[0024] The diagram shows: V01 - Purifying agent storage tank, M01 - Fan, P01 - Purifying agent transfer pump, T01 - Purification tower, P02 - Reflux pump, P04 - Transfer pump, V03 - Flash recovery tank, P05 - Flash discharge pump, T02 - Distillation tower, V04 - Distillation recovery tank, E05 - Reboiler, E04 - Circulating water cooler, C01 - 1# High-speed permanent magnet explosion-proof centrifugal compressor, E03 - Tower bottom liquid heat exchanger, SE01 - 1# Demister, SE02 - 2# Demister, P03 - Discharge pump, V02 - Flash tank, E02 - Flash heat exchanger, P06 - Tower bottom liquid discharge pump, P08 - Distillation tower reflux pump, P07 - Reboiler circulating pump, C02 - 2# High-speed permanent magnet explosion-proof centrifugal compressor. Detailed Implementation

[0025] To better understand the present invention, the invention will be further described below with reference to the accompanying drawings, but the embodiments of the present invention are not limited thereto.

[0026] like Figure 2 As shown, an acid gas purification system based on a dual high-speed permanent magnet explosion-proof centrifugal compressor includes an absorption purification system, an energy-saving flash evaporation system, and a heat pump distillation regeneration system.

[0027] The absorption and purification system includes: a purification agent storage tank V01, a blower M01, a purification agent transfer pump P01, a purification tower T01, a P02 reflux pump, and a discharge pump P03. The inlet flange of the purification agent storage tank V01 is connected to the purification agent inlet pipe to replenish a fixed amount of purification agent (e.g., using MDEA as the purification agent). The outlet flange of the purification agent storage tank V01 is connected to the inlet pipe of the purification agent transfer pump P01 to provide purification agent to the system. The outlet pipe of the purification agent transfer pump P01 is connected to the inlet flange of the purification tower T01 to ensure that the purification agent is replenished. The inlet flange of the purification tower T01 is connected to the outlet pipe of the blower M01. The inlet pipe of the blower M01 is connected to external natural gas and refinery pipelines containing sulfur, hydrogen sulfide, and carbon dioxide. The circulation port of purification tower T01 is connected to the outlet pipe of reflux pump P02, allowing the purifying agent to fully mix and react counter-currently with external natural gas and refinery gases containing sulfur, hydrogen sulfide, and carbon dioxide, ensuring the purification effect. The purified gas outlet pipe of purification tower T01 is connected to the external purified gas connection pipe. The inlet pipe of reflux pump P02 is connected to the circulation outlet pipe of purification tower T01, and a reserved interface is provided on the inlet pipe of reflux pump P02 for connection to the hot side outlet pipe of circulating water cooler E04, realizing the recycling of the purifying agent. The flange of the outlet pipe of purification tower T01 is connected to the inlet pipe of the outlet pump P03, which delivers the purified H2S-rich liquid into the energy-saving flash evaporation system in real time.

[0028] The energy-saving flash evaporation system includes: a transfer pump P04, a flash recovery tank V03, a flash discharge pump P05, a #1 high-speed permanent magnet explosion-proof centrifugal compressor C01, a #1 demister SE01, a V flash tank 02, and a flash heat exchanger E02. The outlet pipe of the discharge pump P03 is connected to the inlet of the flash tank V02 in the energy-saving flash evaporation system. The flash outlet flange of the flash tank V02 is connected to the inlet pipe of the #1 demister SE01. The #1 demister SE01 can further purify the flash vapor from the flash tank V02, allowing gas, liquid, and mist droplets to return to the flash tank V02 through the outlet of the #1 demister SE01, ensuring that the vapor from the #1 demister SE01... The purity of the flash vapor discharged from the E01 outlet meets the standard; the outlet of the #1 demister SE01 is connected to the inlet pipe of the #1 high-speed permanent magnet explosion-proof centrifugal compressor C01. Under the action of the #1 high-speed permanent magnet explosion-proof centrifugal compressor C01, the enthalpy, pressure, and temperature of the flash vapor are all increased; the outlet pipe of the #1 high-speed permanent magnet explosion-proof centrifugal compressor C01 is connected to the hot side inlet pipe of the flash evaporator heat exchanger E02. The high-enthalpy flash vapor compressed by the #1 high-speed permanent magnet explosion-proof centrifugal compressor C01 exchanges heat with the H2S-rich liquid delivered from the transfer pump P04; the hot side outlet pipe of the flash evaporator heat exchanger E02 is connected to the liquid inlet of the flash recovery tank V03. The liquid inlet of the flash recovery tank V03 receives the condensate after heat exchange from the flash vapor; the liquid outlet of the flash recovery tank V03 is connected to the inlet pipe of the flash discharge pump P05, and the condensate is delivered to the external region through the flash discharge pump P05. The cold side of the flash heat exchanger E02 is connected to the outlet pipe of the transfer pump P04; the inlet pipe of the transfer pump P04 is connected to the outlet of the flash tank V02.

[0029] The heat pump distillation regeneration system includes: distillation column T02, distillation recovery tank V04, reboiler E05, circulating water cooler E04, column bottom liquid heat exchanger E03, #2 demister SE02, column bottom liquid discharge pump P06, distillation column reflux pump P08, reboiler circulation pump P07, and #2 high-speed permanent magnet explosion-proof centrifugal compressor C02. The cold-side outlet of flash heat exchanger E02 is connected to the cold-side inlet of bottom liquid heat exchanger E03. The H2S-rich liquid, after heat exchange, is further heated in bottom liquid heat exchanger E03 before entering the feed pipe of distillation column T02. The hot-side inlet of bottom liquid heat exchanger E03 is connected to the outlet of bottom liquid discharge pump P06, and heat exchange is performed using the bottom liquid from distillation column T02 delivered by bottom liquid discharge pump P06. After heat exchange, the bottom liquid is discharged through the hot-side outlet of bottom liquid heat exchanger E03 to the hot-side inlet of circulating water cooler E04 to continue heat exchange with circulating cooling water from the outside. The inlet and outlet of the cold side of circulating water cooler E04 are connected to the inlet and outlet of external circulating cooling water, respectively. The hot-side outlet of circulating water cooler E04 is connected to the outlet of reflux pump P02, and the liquid is returned to purification column T01 for recycling as a purification agent.

[0030] The feed pipe of distillation column T02 is connected to the cold side outlet pipe of the bottom liquid heat exchanger E03. After being reheated by the bottom liquid heat exchanger E03, the temperature of the H2S rich liquid is increased again, so that the temperature entering distillation column T02 is close to the required temperature, reducing the need for external steam replenishment. The vapor outlet pipe of distillation column T02 is connected to the inlet of demister SE02 (No. 2), where thorough gas-liquid separation occurs. After separation by demister SE02, the liquid droplets return to distillation column T02 through the liquid outlet. The vapor phase, after further separation by demister SE02, is then connected to the inlet pipe of high-speed permanent magnet explosion-proof centrifugal compressor C02 through the outlet pipe of demister SE02 for compression. This increases the vapor phase enthalpy, temperature, and pressure before it is discharged from the outlet of high-speed permanent magnet explosion-proof centrifugal compressor C02. The outlet pipe of high-speed permanent magnet explosion-proof centrifugal compressor C02 is connected to the shell inlet pipe of reboiler E05. Reboiler E05 is... The high-enthalpy vapor phase discharged from the outlet of the No. 2 high-speed permanent magnet explosion-proof centrifugal compressor CO2 undergoes heat exchange, causing the circulating liquid in the reboiler E05 tube layer to heat up. After heat exchange, the vapor phase becomes condensate and is discharged from the shell outlet of the reboiler E05 into the distillation recovery tank V04. The outlet of the distillation recovery tank V04 is connected to the inlet pipe of the distillation column reflux pump P08. The outlet pipe of the distillation column reflux pump P08 is connected to the reflux pipe of the distillation column T02, and a branch pipe on the outlet pipe of the distillation column reflux pump P08 transports part of the condensate to external process treatment. The inlet pipe of the reboiler E05 tube layer is connected to the outlet of the reboiler circulating pump P07, and the outlet pipe of the reboiler E05 tube layer is connected to the circulating feed inlet of the distillation column T02. The inlet of the reboiler circulating pump P07 is connected to the circulating outlet pipe of the distillation column T02. The discharge pipe of distillation column T02 is connected to the inlet pipe of column bottom liquid discharge pump P06, and the column bottom liquid is transported to column bottom liquid heat exchanger E03 for heat exchange, further improving the heat utilization rate.

[0031] Figure 2 S1-S32 all refer to materials. In the process, materials can be specifically defined as raw material gas, flash vapor, purified gas, bottom liquid, rich liquid, condensate, etc., or even simply referred to as logistics.

[0032] A novel acid gas purification process based on a high-speed permanent magnet explosion-proof centrifugal compressor is as follows:

[0033] The raw material gas S1 (whose main components, besides H2S, also include H2, CO2, CH4, C2, C3, C4, and C5 gases) enters the purification tower T01 from the bottom via fan M01, with the gaseous stream flowing from bottom to top. The purifying agent liquid makeup stream S4 (MDEA solution) enters from the top of the purification tower T01, flowing from top to bottom. A portion of the bottom liquid S9 in the purification tower T01 is mixed with the distilled and cooled lean amine liquid S10 via reflux pump P02 and then returned to the purification tower T01. The gaseous stream and the absorbent liquid stream mix and react thoroughly in a counter-current manner. Acidic components such as H2S are absorbed by the absorbent during this process, forming a rich liquid S12 at the bottom of the purification tower T01. The purified gas S6, meeting the purification standards, then enters the next process. In this process, the bottom liquid S9 of the purification tower T01 is introduced. The bottom liquid is a circulating stream, which allows the purifying agent to be fully mixed with the acid gas, increases the concentration of the rich liquid, reduces the amount of lean amine liquid to be recycled, ensures the purification effect, and reduces the energy consumption of the subsequent distillation process.

[0034] The rich liquid S12 is pumped into the flash tank V02 of the energy-saving flash evaporation system via the discharge pump P03, where gas-liquid separation takes place. The #1 demister SE01 further purifies the flash vapor from the flash tank V02, allowing liquid droplets to return to the flash tank V02 via the discharge port of the #1 demister SE01, ensuring that the purity of the flash vapor S36 discharged from the outlet of the #1 demister SE01 meets the standards. The flash vapor S17 discharged from the #1 demister SE01 is subjected to the action of the #1 high-speed permanent magnet explosion-proof centrifugal compressor C01, which increases its enthalpy, pressure, and temperature. The high-temperature, high-enthalpy flash vapor S18 after compression exchanges heat with the rich liquid S14 from the transfer pump P04 through the flash evaporator heat exchanger E02, further increasing the temperature of the rich liquid. The condensate after the flash vapor heat exchange is collected in the flash recovery tank V03 and then pumped to the outer area via the flash discharge pump P05.

[0035] The rich liquid S20 is further heated to the required temperature in the bottom liquid heat exchanger E03 before entering the distillation column T02, thereby reducing the consumption of external steam. The bottom liquid of the distillation column is gradually cooled by two heat exchangers connected in series, bottom liquid heat exchanger E03 and circulating water cooler E04, and finally returned to the purification column T01 via reflux pump P02 for recycling as a purification agent. The circulating water cooler E04 uses circulating cooling water as the coolant.

[0036] The vapor stream S23 from the top of distillation column T02 undergoes thorough gas-liquid separation in demister SE02 (No. 2). After separation, the liquid droplets return to distillation column T02 through the outlet of demister SE02. The separated vapor stream S24 is compressed by high-speed permanent magnet explosion-proof centrifugal compressor C02 (No. 2), increasing its enthalpy, temperature, and pressure. Then, it passes through reboiler E05, where the circulating bottom liquid is heated through heat exchange. After heat exchange, the vapor stream S28 becomes condensate S30 and is discharged from the outlet of reboiler E05 into distillation recovery tank V04. The condensate S31 from distillation recovery tank V04 is partially returned to distillation column T02 and partially transported to external processes via distillation column reflux pump P08. A portion of the bottom liquid S33 from distillation column T02 is transported to reboiler E05 for heating via reboiler circulation pump P07. Another portion of the bottom liquid from distillation column T02 is transported to bottom liquid heat exchanger E03 via bottom liquid discharge pump P06 for heat exchange, further improving heat utilization.

[0037] contrast Figure 1 and Figure 2 Comparing two different acid gas purification systems, the acid gas purification system based on dual high-speed permanent magnet explosion-proof centrifugal compressors has the following advantages:

[0038] 1) Compared to existing acid gas purification systems, the absorption purification system in this invention adds a flash evaporation energy recovery system (with a #1 high-speed permanent magnet explosion-proof centrifugal compressor as the core equipment), specifically as follows: The acid gas (mainly containing sulfur, hydrogen sulfide, carbon dioxide, etc.) is purified by the absorption purification system, and then the rich liquid enters the energy-saving flash evaporation system's flash tank VO2 for flash separation. The flash vapor generated by the energy-saving flash evaporation system is further compressed by the #1 high-speed permanent magnet explosion-proof centrifugal compressor CO1. After compression by the #1 high-speed permanent magnet explosion-proof centrifugal compressor CO1, the temperature, pressure, and enthalpy of the low-enthalpy flash vapor are increased, allowing for sufficient heat exchange with the flash-evaporated rich liquid. This not only achieves flash vapor separation but also further increases the temperature of the rich liquid, reducing steam consumption during the distillation process.

[0039] 2) Compared with the existing acid gas purification system, the distillation regeneration device system of this invention introduces heat pump distillation regeneration technology (with the No. 2 high-speed permanent magnet explosion-proof centrifugal compressor as the core equipment), as follows: the gas phase at the top of the distillation column T02 is recompressed by the No. 2 high-speed permanent magnet explosion-proof centrifugal compressor CO2 and then enters the reboiler E05 to fully exchange heat with the bottom liquid of the column, which replenishes the heat of the circulating liquid in the reboiler E05, reduces the amount of external steam input, greatly improves the energy utilization efficiency of the system, and also saves operating costs.

[0040] 3) In this invention, the rich liquid in the bottom of the heat pump distillation regeneration system, after heat exchange with flash vapor in the bottom liquid heat exchanger E03, undergoes another thorough heat exchange, reusing the heat from the bottom liquid in distillation column T02. This raises the temperature of the feed liquid entering distillation column T02, reducing the consumption of external steam and further optimizing the energy consumption of the distillation column T02 system. Simultaneously, the temperature of the bottom liquid in the distillation column decreases after heat exchange in the bottom liquid heat exchanger, significantly reducing the amount of circulating cooling water used in the absorption stage, further optimizing system investment and operating costs.

[0041] 4) Compared with the existing acid gas purification system, the absorption purification device system of the present invention adds a rich liquid reflux system for the purification tower, as follows: Part of the bottom liquid of the purification tower T01 is mixed with the lean amine liquid cooled by distillation through the reflux pump PO2 and then returned to the purification tower T01. The gas phase stream and the absorbent liquid phase stream are fully mixed and reacted in the opposite direction, which increases the concentration of rich liquid, reduces the amount of lean amine liquid recycled, ensures the purification effect, and reduces the energy consumption of the subsequent distillation process.

[0042] 5) Compared to traditional acid gas purification systems, the CO1-1# and CO2-2# high-speed permanent magnet explosion-proof centrifugal compressors used in this invention both employ high-speed permanent magnet explosion-proof centrifugal compressors with an efficiency of over 95.5%. Compared to traditional positive displacement compressors and centrifugal gearbox compressors, they offer advantages such as higher energy conversion efficiency, more compact and simpler structure, wider operating range, convenient maintenance, lower noise, and higher reliability. This further reduces the energy consumption of the acid gas absorption and purification system, while also lowering system maintenance costs.

[0043] In the description of this invention, it should be noted that the terms used, such as "flange," "pipeline," "tower top," "gas phase," "liquid phase," "flash evaporation," "tower bottom," "enthalpy value," "external vapor," "pipe layer," "shell layer," "rich liquid," and "meets standards," are technical terms used only for the convenience of describing this invention and for simplifying the description, and are not intended to indicate or imply that the described device or component must have a specific structure and operation, and therefore should not be construed as limiting the invention. Furthermore, the terms "1#" and "2#" are used only for descriptive purposes and should not be construed as indicating or implying relative importance.

[0044] Specific examples have been used to illustrate the principles and implementation methods of this invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of this invention. Furthermore, those skilled in the art will recognize that, based on the ideas of this invention, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of this invention.

Claims

1. An acid gas purification system based on a dual high-speed permanent magnet explosion-proof centrifugal compressor, characterized in that: The system includes an absorption and purification system, an energy-saving flash evaporation system, and a heat pump distillation and regeneration system. The absorption and purification system includes a purifying agent storage tank, a fan, and a purification tower. The inlet of the purifying agent storage tank is connected to the purifying agent feed pipe, the outlet of the purifying agent storage tank is connected to the purification tower, and the air inlet of the purification tower is connected to the fan. The circulation pipe of the purification tower is connected to the outlet pipe of the reflux pump, the inlet pipe of the reflux pump is connected to the circulation outlet pipe of the purification tower, and is also connected to the hot side outlet pipe of the circulating water cooler. The outlet of the purification tower is connected to the flash evaporation tank. The energy-saving flash evaporation system includes: a flash recovery tank, a No. 1 high-speed permanent magnet explosion-proof centrifugal compressor, a No. 1 demister, a flash tank, and a flash heat exchanger; the flash tank is connected to the No. 1 demister; the outlet of the No. 1 demister is connected to the inlet pipe of the No. 1 high-speed permanent magnet explosion-proof centrifugal compressor, the outlet pipe of the No. 1 high-speed permanent magnet explosion-proof centrifugal compressor is connected to the hot side inlet pipe of the flash heat exchanger, the hot side outlet pipe of the flash heat exchanger is connected to the liquid inlet of the flash recovery tank; the cold side of the flash heat exchanger is connected to the outlet of the flash tank; the cold side of the flash heat exchanger is connected to the outlet of the flash tank; the flash heat exchanger cold side... The side interface is connected to the outlet pipe of the transfer pump; the inlet pipe of the transfer pump is connected to the outlet of the flash tank; the blower is connected to the pipelines of natural gas from the outside and gas containing hydrogen sulfide and carbon dioxide from the refinery; the purified gas outlet pipe of the purification tower is connected to the external purified gas connection pipe; the outlet flange of the purification agent storage tank is connected to the inlet pipe of the purification agent delivery pump, and the outlet pipe of the purification agent delivery pump is connected to the flange of the purification tower inlet pipe; the outlet flange of the purification tower outlet pipe is connected to the inlet pipe of the discharge pump, and the outlet pipe of the discharge pump is connected to the inlet of the flash tank. The heat pump distillation regeneration system includes a distillation column, a distillation recovery tank, a reboiler, a circulating water cooler, a column bottom liquid heat exchanger, a #2 demister, and a #2 high-speed permanent magnet explosion-proof centrifugal compressor. The flash evaporator heat exchanger's cold-side outlet is connected to the cold-side inlet of the column bottom liquid heat exchanger. The hot-side inlet pipe of the column bottom liquid heat exchanger is connected to the lower part of the distillation column. The hot-side outlet pipe of the column bottom liquid heat exchanger is connected to the hot-side inlet pipe of the circulating water cooler. The hot-side outlet pipe of the circulating water cooler is connected to the outlet pipe of the reflux pump. The upper feed pipe of the distillation column is connected to the cold-side outlet pipe of the column bottom liquid heat exchanger. The distillation column is connected to the #2 demister, and the #2 demister's outlet pipe is connected to the #2 high-speed permanent magnet compressor. The explosion-proof centrifugal compressor inlet pipe is connected; the outlet pipe of the No. 2 high-speed permanent magnet explosion-proof centrifugal compressor is connected to the reboiler shell inlet pipe; the reboiler shell outlet is connected to the distillation recovery tank; the distillation recovery tank outlet is connected to the distillation column reflux pipe; the reboiler tube inlet pipe is connected to the distillation column circulation outlet pipe; the reboiler tube outlet pipe is connected to the distillation column circulation feed inlet; the reboiler tube inlet pipe is connected to the reboiler circulation pump outlet, and the reboiler circulation pump inlet is connected to the distillation column circulation outlet pipe.

2. The acid gas purification system based on a dual high-speed permanent magnet explosion-proof centrifugal compressor according to claim 1, characterized in that: The inlet pipe of the heat exchanger on the hot side of the column bottom liquid is connected to the outlet pipe of the column bottom liquid discharge pump, and the inlet pipe of the column bottom liquid discharge pump is connected to the lower part of the distillation column.

3. The acid gas purification system based on a dual high-speed permanent magnet explosion-proof centrifugal compressor according to claim 1, characterized in that: The liquid outlet of the distillation recovery tank is connected to the inlet pipe of the distillation column reflux pump; the discharge outlet pipe of the distillation column reflux pump is connected to the distillation column reflux pipe.

4. The acid gas purification system based on a dual high-speed permanent magnet explosion-proof centrifugal compressor according to claim 3, characterized in that: A branch pipe is provided on the pipeline connecting the discharge port pipe of the distillation column reflux pump to the reflux pipe of the distillation column.

5. The acid gas purification system based on a dual high-speed permanent magnet explosion-proof centrifugal compressor according to claim 1, characterized in that: The inlet and outlet of the circulating water cooler on the cold side are respectively connected to the external circulating cooling water inlet pipe and outlet pipe.

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