Microdroplet double-enhanced liquefied gas desulfurization reactor, reaction system and reaction method

Abstract

Micro-droplet double-strengthened liquefied gas desulfurization reactor, reaction system and reaction method relate to the field of liquefied gas desulfurization treatment, the desulfurization reactor has liquefied gas liquid discharge port in the upper part and amine liquid discharge port in the lower part, the desulfurization reactor has amine liquid area in the lower part, liquefied gas liquid area in the upper part and mixing area formed by the junction of amine liquid area and liquefied gas liquid area, the liquefied gas liquid area is provided with amine liquid nozzle capable of spraying amine liquid droplets, the amine liquid area is provided with liquefied gas liquid nozzle capable of spraying liquefied gas droplets, the pressure environment in the desulfurization reactor is 1.6 MPa or more, so as to keep the liquefied gas liquid entering the desulfurization reactor in liquid phase state, the liquefied gas droplets are desulfurized and mass transfer in the amine liquid area and flow upwards, sequentially contact and react with amine droplets in the mixing area and amine droplets in the liquefied gas liquid area, and complete the desulfurization treatment of liquefied gas. The present application is used to solve the problems of slow desulfurization speed and poor desulfurization effect of hydrogen sulfide in liquefied gas in the removal process.

Description

Technical Field

[0001] This invention relates to the field of liquefied petroleum gas (LPG) desulfurization treatment, specifically to a micro-droplet dual-enhanced LPG desulfurization reactor, reaction system, and reaction method. Background Technology

[0002] During hydrocracking, most of the various sulfides in the feedstock are converted into hydrogen sulfide (H2S), which enters products such as liquefied petroleum gas (LPG). Hydrogen sulfide (H2S) is highly corrosive to pipelines and storage containers, and can also cause catalyst poisoning and deactivation in subsequent processing. When used as a civilian fuel, it generates SO2. X It pollutes the environment and causes acid rain, among other things.

[0003] There are many effective methods for removing H2S in industry, which can be broadly classified into two categories: wet and dry methods. Common wet desulfurization methods include chemical absorption, physical absorption, physicochemical absorption, and wet oxidation, suitable for applications with large gas volumes and high H2S content. Dry desulfurization is often used for treating low-sulfur gases, and common methods include membrane separation, molecular sieve methods, pressure swing adsorption (PSA), non-renewable fixed-bed adsorption, and cryogenic separation. In the petrochemical industry, chemical absorption is widely used to remove H2S from liquefied petroleum gas (LPG), with commonly used absorbents including N-methyldiethanolamine (MDEA) solution, NaOH solution, or ammonia.

[0004] Currently, the main method for removing hydrogen sulfide (H2S) from liquefied petroleum gas (LPG) is through a desulfurization tower. Specifically, gaseous LPG is passed into a hydrogen sulfide absorption liquid. However, when using this method, the gaseous LPG quickly overflows from the absorption liquid, resulting in a short reaction time. The amine solution does not completely absorb the absorption liquid, leading to a slow desulfurization rate. Furthermore, the desulfurized LPG often fails desulfurization tests. Summary of the Invention

[0005] The present invention aims to provide a micro-droplet dual-enhanced liquefied gas desulfurization reactor, reaction system and reaction method to solve the problem of slow desulfurization speed and poor desulfurization effect in the removal of hydrogen sulfide in liquefied gas.

[0006] To solve the above technical problems, the specific solution adopted by the present invention is as follows: a micro-droplet dual-enhanced liquefied gas desulfurization method, which has a reaction chamber formed by a liquefied gas-liquid zone and an amine liquid zone, and a mixed flow zone is formed at the junction of the upper liquefied gas-liquid zone and the lower amine liquid zone. The amine liquid is dispersed into amine droplets and then introduced into the liquefied gas-liquid zone. The amine droplets flow downward and first enter the mixed flow zone, and then merge into the amine liquid zone. In this process, the liquefied gas to be desulfurized is dispersed into liquefied gas droplets and then introduced into the amine liquid zone. The liquefied gas droplets first undergo a desulfurization mass transfer in the amine liquid zone and then float upward to the mixed flow zone, where they collide and contact with the amine liquid and amine droplets in the mixed flow zone to achieve a secondary desulfurization mass transfer. After the secondary desulfurization mass transfer, the liquefied gas droplets float upward and merge into the liquefied gas-liquid zone, and then undergo a tertiary desulfurization mass transfer with the amine droplets in the liquefied gas-liquid zone to complete the desulfurization of the liquefied gas.

[0007] As a further optimization of the above technical solution, both the primary desulfurization mass transfer and the tertiary desulfurization mass transfer are countercurrent contact mass transfer.

[0008] As a further optimization of the above technical solution, the amine droplets are millimeter-sized droplets, and the liquefied gas droplets are micrometer-sized droplets.

[0009] As a further optimization of the above technical solution, the angle between the tilt angle of the amine droplets when they are ejected and the vertical direction is 40-80°.

[0010] A micro-droplet dual-enhanced liquefied gas desulfurization reactor is disclosed. The desulfurization reactor has an upper liquefied gas-liquid outlet and a lower amine outlet. The desulfurization reactor contains a lower amine zone, an upper liquefied gas-liquid zone, and a mixed flow zone formed at the boundary between the amine zone and the liquefied gas-liquid zone. An amine nozzle capable of spraying amine droplets is installed in the liquefied gas-liquid zone, and a liquefied gas-liquid nozzle capable of spraying liquefied gas droplets is installed in the amine zone. The pressure environment inside the desulfurization reactor is above 1.6 MPa to keep the liquefied gas entering the desulfurization reactor in a liquid phase state. The liquefied gas droplets undergo desulfurization and mass transfer in the amine zone and flow upward, sequentially contacting and reacting with the amine droplets in the mixed flow zone and the amine droplets in the liquefied gas-liquid zone to complete the desulfurization treatment of the liquefied gas.

[0011] As a further optimization of the above technical solution, the amine liquid nozzle is a rotating impeller nozzle.

[0012] As a further optimization of the above technical solution, the desulfurization reactor is equipped with a packing stabilization section for separating liquefied gas and amine liquid. Multiple packing stabilization sections are provided, with at least one packing stabilization section located above the amine liquid nozzle and at least one packing stabilization section located below the liquefied gas and amine liquid nozzle.

[0013] As a further optimization of the above technical solution, the packing stabilization section includes a packing cover plate and a packing support plate arranged laterally in the desulfurization reactor. The packing cover plate is located above the packing support plate, and a material holding space is provided between the packing cover plate and the packing support plate to fill the packing.

[0014] As a further optimization of the above technical solution, the filler is one or more of the following: Pall rings, stepped rings, rectangular saddles, metal ring rectangular saddles, and titanium nanofiber wire mesh.

[0015] A micro-droplet dual-enhanced liquefied gas desulfurization reaction system includes a lean amine buffer tank, a purified liquefied gas amine separation tank, a liquefied gas deamine coalescing device, and the aforementioned desulfurization reactor. The lean amine buffer tank is connected to the amine nozzle of the desulfurization reactor via a lean amine delivery pipeline to deliver lean amine into the desulfurization reactor. The liquefied gas-liquid nozzle of the desulfurization reactor is connected to a liquefied gas inlet pipe to supply the liquefied gas to be desulfurized into the desulfurization reactor. The amine outlet of the desulfurization reactor is connected to the inlet of a solvent regeneration device via a rich amine delivery pipeline. The liquefied gas-liquid outlet of the desulfurization reactor is connected sequentially to the purified liquefied gas amine separation tank and the liquefied gas deamine coalescing device via pipelines.

[0016] As a further optimization of the above technical solution, a liquid-liquid hydrocyclone is connected to the amine liquid delivery pipeline to separate the liquefied gas in the amine liquid. The liquefied gas outlet of the liquid-liquid hydrocyclone is connected to the liquefied gas inlet pipe, and the amine liquid outlet of the liquid-liquid hydrocyclone is connected to the inlet of the solvent regeneration device.

[0017] As a further optimization of the above technical solution, a delivery pump is connected to the lean amine liquid delivery pipeline.

[0018] As a further optimization of the above technical solution, the delivery pump is a liquefied gas desulfurization liquid pump.

[0019] As a further optimization of the above technical solution, the outlet of the solvent regeneration device is connected to the lean amine buffer tank.

[0020] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0021] 1. This invention disperses the liquefied petroleum gas (LPG) to be desulfurized into LPG droplets and introduces them into an amine liquid environment for desulfurization mass transfer. The LPG droplets contact the amine liquid for mass transfer and float to the surface under the action of buoyancy, separating from the amine liquid. Compared with gaseous LPG, liquid LPG droplets can prolong their reaction time in the amine liquid, thereby improving the desulfurization effect.

[0022] 2. During the process of liquefied gas droplets rising in the amine liquid, the amine liquid flows downward. After the liquefied gas droplets merge into the liquefied gas-liquid zone, the amine droplets flow downward while the liquefied gas-liquid zone flows upward. Therefore, the mass transfer mode of liquefied gas-liquid in both the amine liquid zone and the liquefied gas-liquid zone is countercurrent contact mass transfer, which can enhance the mass transfer effect between liquefied gas and amine liquid. When the liquefied gas droplets rise to the mixed flow zone, the amine droplets flow downward into the mixed flow zone. In the mixed flow zone, the amine droplets collide and contact with the liquefied gas droplets to carry out desulfurization mass transfer, which further improves the desulfurization efficiency of liquefied gas.

[0023] 3. This invention increases the contact area between the lean amine solution and the liquefied gas by setting up dual nozzles in the desulfurization reactor. The amine solution sprayed from the amine solution nozzle consists of millimeter-sized droplets, while the liquefied gas sprayed from the liquefied gas-liquid nozzle consists of micron-sized droplets. This achieves dual enhancement of the mass transfer process, which can greatly improve the mixing effect, deepen the reaction, and improve the desulfurization efficiency.

[0024] 4. The packing stabilization section set in this invention can separate the liquefied gas and liquid in the amine liquid and the amine liquid in the liquefied gas and liquid, thereby making the amine liquid and liquefied gas and liquid discharged from the desulfurization reactor relatively pure and reducing the pressure of subsequent liquefied gas and liquid and amine liquid treatment. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the desulfurization reactor in this invention;

[0026] Figure 2 This is a flowchart of the desulfurization reaction system in Embodiment 3 of the present invention;

[0027] Figure 3 This is a flowchart of the desulfurization reaction system in Embodiment 4 of the present invention;

[0028] Attached reference numerals: 1. Buffer tank; 2. LPG desulfurization liquid pump; 3. Desulfurization reactor; 4. Packing cover plate; 5. Packing; 6. Packing support plate; 7. Amine liquid nozzle; 8. LPG liquid nozzle; 9. LPG amine separation tank; 10. LPG deamine coalescer; 11. Liquid-liquid cyclone separator; 12. LPG liquid outlet; 13. Amine liquid outlet; 14. LPG liquid zone; 15. Mixed flow zone; 16. Amine liquid zone. Detailed Implementation

[0029] Example 1

[0030] like Figure 1 As shown, this embodiment is a micro-droplet dual-enhanced liquefied gas desulfurization reactor. The desulfurization reactor 3 has an upper liquefied gas-liquid outlet 12 and a lower amine liquid outlet 13. The desulfurization reactor 3 contains a lower amine liquid zone 16, an upper liquefied gas-liquid zone 14, and a mixed flow zone 15 formed at the boundary between the amine liquid zone 16 and the liquefied gas-liquid zone 14. The pressure environment within the desulfurization reactor 3 is above 1.6 MPa to maintain the liquefied gas-liquid entering the desulfurization reactor 3 in a liquid phase state.

[0031] Amine liquid nozzles 7, capable of spraying amine liquid droplets, are installed in the liquefied gas-liquid zone 14, and liquefied gas-liquid nozzles 8, capable of spraying liquefied gas droplets, are installed in the amine liquid zone 16. The amine liquid introduced into the amine liquid nozzles 7 is lean amine liquid, and the liquefied gas introduced into the liquefied gas-liquid nozzles 8 is liquefied gas to be desulfurized containing hydrogen sulfide. The lean amine liquid is used to remove hydrogen sulfide from the liquefied gas to be desulfurized. Therefore, the amine liquid discharged from the amine liquid outlet 13 is rich amine liquid with hydrogen sulfide removed from the liquefied gas, and the liquefied gas-liquid outlet 12 is desulfurized liquefied gas. In the desulfurization reactor 3, the area below the amine liquid nozzles 7 and above the liquefied gas-liquid nozzles 8 constitutes the desulfurization mass transfer section. The desulfurization mass transfer process of liquefied gas and liquid mainly takes place in this desulfurization mass transfer section. The liquid flow above and below the desulfurization mass transfer section is relatively stable, which is more conducive to the separation of amine liquid and liquefied gas-liquid under gravity.

[0032] During the reaction, liquefied gas droplets undergo desulfurization and mass transfer in the amine liquid zone 16 and flow upwards, sequentially contacting and reacting with amine droplets in the mixed flow zone 15 and the amine liquid zone 14 to complete the desulfurization treatment of the liquefied gas. The amine droplets fall into the mixed flow zone 15 and then flow into the amine liquid zone 16. Due to the intense fluid turbulence in the desulfurization mass transfer section of the desulfurization reactor 3, the mixed flow zone 15 fluctuates continuously, thus there is no obvious solution stratification. The mixed flow zone 15 can be positioned in the middle of the desulfurization reactor 3 by controlling the feed rates of amine liquid and liquefied gas liquid. Generally speaking, the liquefied gas liquid zone 14 above the mixed flow zone 15 mainly consists of lighter liquefied gas liquid, with amine liquid as the dispersed phase of amine droplets and liquefied gas liquid as the continuous phase; the amine liquid zone 16 below the mixed flow zone 15 mainly consists of heavier amine liquid, with amine liquid as the continuous phase and liquefied gas liquid as the dispersed phase of liquefied gas droplets.

[0033] The amine liquid is dispersed into amine droplets and introduced into the amine nozzle 7 inside the desulfurization reactor 3. The amine nozzle 7 is a rotating impeller nozzle. After being atomized into millimeter-sized droplets in the amine nozzle 7, the amine liquid flows downward and impacts the impeller surface, driving the impeller to rotate. Driven by the impeller, the droplets are flung out laterally, spreading throughout the cross-section of the desulfurization reactor 3 in the form of millimeter-sized droplets. This increases the contact area between the lean amine liquid and the liquefied gas-liquid mixture. At the same time, the amine droplets flung out laterally have a certain initial velocity and tilt angle, thus achieving a swirling mixing effect in the liquefied gas-liquid environment and improving the removal efficiency of hydrogen sulfide. The small amine droplets flow downward and collide with the liquefied gas micro-droplets flowing from bottom to top in the turbulent mixed flow zone 15, carrying out desulfurization mass transfer. Then, the small amine droplets continue to flow downward and dissolve in the amine liquid. The angle between the outlet of the rotating impeller nozzle and the vertical direction is 40-80°, so that the amine droplets make an angle of 40-80° with the vertical direction when they are sprayed. When the angle between the outlet and the vertical direction is 60°, the turbulence formed by the small amine droplets in the liquefied gas is more obvious, and the removal efficiency of the sulfurizer gas in the liquefied gas is better at this time.

[0034] The liquefied gas-liquid nozzle 8 is a metal micro-orifice nozzle. Liquefied gas enters the desulfurization reactor 3 through the nozzle 8, where it is atomized into micron-sized droplets. These droplets then contact the amine liquid flowing downwards for desulfurization and mass transfer. Under buoyancy, the gas continues to flow upwards, colliding with the small droplets in the turbulent mixed flow zone 15 for further desulfurization and mass transfer. It then continues to flow upwards, dissolving in the liquefied gas-liquid mixture, and finally flows to the liquefied gas-liquid zone 14 at the top of the desulfurization reactor 3. The amine liquid in the liquefied gas-liquid zone 14 returns to the mixed flow zone 15 and amine liquid zone 16 under gravity, and is finally discharged through the amine liquid outlet 13. The liquefied gas-liquid mixture in the liquefied gas-liquid zone 14 is discharged through the liquefied gas-liquid outlet 12 at the top of the desulfurization reactor 3, completing the desulfurization of the liquefied gas. Both the micro-orifice nozzle and the rotating impeller nozzle are existing technologies, and their specific structures will not be described in detail here.

[0035] It should be noted that the velocity of amine droplets and liquefied gas droplets is determined by the feed rate. Different processes require different feed rates, but in order to ensure the desulfurization effect, the volumetric flow rate of amine liquid is generally slightly greater than that of liquefied gas.

[0036] The liquefied gas-liquid outlet 12 can be located at the top of the desulfurization reactor 3, or it can be located in the middle and upper part of the desulfurization reactor 3 depending on the flow of liquefied gas and amine liquid during the reaction process. However, it is necessary to ensure that the liquefied gas-liquid outlet is above the amine liquid nozzle 7.

[0037] Example 2

[0038] This embodiment is an improvement on embodiment 1. Its main structure is the same as that of embodiment 1. The improvement is that the desulfurization reactor 3 is provided with a packing stabilization section for separating liquefied gas and amine liquid. Multiple packing stabilization sections can be set. At least one packing stabilization section is located above the amine liquid nozzle 7 and at least one packing stabilization section is located below the liquefied gas and liquid nozzle 8. That is, the packing stabilization sections are respectively set above and below the desulfurization mass transfer section. Since the liquid flow above and below the desulfurization mass transfer section is relatively stable, it is more conducive to the separation of amine liquid and liquefied gas and liquid by the set packing stabilization section.

[0039] In this embodiment, there are two packing stabilization sections. One packing stabilization section is located above the amine liquid nozzle 7, and the other packing stabilization section is located below the liquefied gas-liquid nozzle 8. The one above the amine liquid nozzle 7 is the upper packing stabilization section, and the one below the liquefied gas-liquid nozzle 8 is the lower packing stabilization section. The function of both the upper and lower packing stabilization sections is to separate the amine liquid and the liquefied gas-liquid by gravity.

[0040] The upper packing stabilization section consists of, from top to bottom, a packing cover plate 4, packing material 5, and a packing support plate 6. Both the packing cover plate 4 and the packing support plate 6 are horizontally arranged within the desulfurization reactor 3. Both the packing cover plate 4 and the packing support plate 6 have through holes to allow free flow of amine liquid and liquefied gas / liquid. The packing cover plate 4 and the packing support plate 6 are spaced apart within the desulfurization reactor 3 to create a space for filling the packing material 5. The packing material 5 can be a commonly used packing such as Pall rings, stepped rings, rectangular saddles, or metal ring rectangular saddles, or it can be titanium nanofiber wire mesh. The main function of the packing material is aggregation and separation. Amine droplets in the liquefied gas / liquid aggregate on the packing material 5 upon encountering it. As the amount of amine droplets accumulating on the packing material 5 increases, the droplets gradually converge from their initial micron-sized size, increasing their volume and facilitating downward flow under gravity. The upper packing stabilization section enables the initial recovery of amine liquid within the desulfurization reactor 3, improving the utilization rate of amine liquid, reducing amine liquid loss, and resulting in significant economic benefits.

[0041] The lower packing stabilization section is used to separate liquefied gas from the amine solution. Its structure is the same as the upper packing stabilization section, consisting of a packing cover plate, packing material, and a packing support plate from top to bottom. Both the packing cover plate and the packing support plate are horizontally positioned within the desulfurization reactor. The packing material is filled between the packing cover plate and the packing support plate. Common packing materials such as Pall rings, stepped rings, rectangular saddles, or metal ring rectangular saddles can be used, or titanium nanofiber wire mesh can be used. The main function of the packing material is aggregation and separation; liquefied gas droplets in the amine solution aggregate on the packing material, reducing the amount of liquefied gas droplets discharged with the amine solution from the desulfurization reactor 3. The lower packing stabilization section can initially separate liquefied gas from the amine-rich solution at the bottom of the reactor, improving the liquefied gas recovery rate and the efficiency of the subsequent solvent regeneration unit.

[0042] Therefore, by setting up a packing stabilization section, the liquefied gas-liquid in the amine liquid and the amine liquid in the liquefied gas-liquid can be separated, thereby making the amine liquid and liquefied gas-liquid discharged from the desulfurization reactor 3 relatively pure, reducing the pressure of subsequent liquefied gas-liquid and amine liquid treatment.

[0043] It should be noted that in this embodiment, the liquefied gas-liquid outlet 12 can be located at the top of the desulfurization reactor 3 or at the middle and upper part of the desulfurization reactor 3, but it is necessary to ensure that the liquefied gas-liquid outlet is located above the upper packing stabilization section.

[0044] Example 3

[0045] like Figure 2 As shown, this embodiment is a micro-droplet dual-enhanced liquefied gas desulfurization reaction system, including a lean amine buffer tank 1, a purified liquefied gas amine separation tank 9, a liquefied gas deamine coalescing device 10, and the desulfurization reactor 3 in the above embodiment 1 or embodiment 2.

[0046] The lean amine buffer tank 1 is connected to the amine spray nozzle 7 of the desulfurization reactor 3 through the lean amine delivery pipeline to deliver lean amine into the desulfurization reactor 3. The liquefied gas spray nozzle 8 of the desulfurization reactor 3 is connected to the liquefied gas inlet pipe to supply the liquefied gas to be desulfurized into the desulfurization reactor 3.

[0047] The amine outlet 13 of the desulfurization reactor 3 is connected to the inlet of the solvent regeneration device through a rich amine liquid conveying pipeline. In the solvent regeneration device, hydrogen sulfide is removed from the rich amine liquid, so that the rich amine liquid is restored to a lean amine liquid. The outlet of the solvent regeneration device is connected to the lean amine liquid buffer tank 1 to realize the recycling of amine liquid.

[0048] The liquefied gas-liquid outlet 12 of the desulfurization reactor 3 is connected in sequence to the purified liquefied gas amine separation tank 9 and the liquefied gas amine removal coalescing device 10 via pipelines. The purified liquefied gas amine separation tank 9 is used for preliminary amine separation of liquefied gas and liquid, and the liquefied gas amine removal coalescing device 10 is used to send the liquefied gas and liquid to the mercaptan removal section after deep amine removal, thus completing the desulfurization treatment of liquefied gas.

[0049] To ensure the smooth delivery of the amine solution from the lean amine buffer tank 1 to the amine spray nozzle 7, a delivery pump is connected to the lean amine delivery pipeline. The delivery pump is a liquefied gas desulfurization pump 2. The purified liquefied gas amine separation tank 9, the liquefied gas deamine coalescer 10, and the liquefied gas desulfurization pump are all existing technology products, and their structures will not be described in detail here.

[0050] Example 4

[0051] like Figure 3 As shown, this embodiment is an improvement on embodiment 3. Its main structure is the same as that of embodiment 4. The improvement is that a liquid-liquid hydrocyclone 11 is connected to the amine liquid conveying pipeline. The liquid-liquid hydrocyclone 11 is used to separate amine liquid and liquefied gas. The liquid-liquid hydrocyclone 11 has a liquefied gas outlet and an amine liquid outlet. The liquefied gas outlet is connected to the liquefied gas inlet pipe. The amine liquid outlet of the liquid-liquid hydrocyclone 11 is connected to the inlet of the solvent regeneration device.

[0052] The liquid-liquid hydrocyclone 11 separates the liquefied gas from the rich amine liquid and transmits it to the liquefied gas inlet pipe through the liquefied gas outlet. On the one hand, this can make the rich amine liquid entering the solvent regeneration device relatively pure, avoiding the impact of the rich amine liquid containing liquefied gas on the regeneration of the lean amine liquid. On the other hand, the separated liquefied gas is reintroduced into the liquefied gas inlet pipe and then into the desulfurization reactor 3, where the liquefied gas can be desulfurized a second time. The desulfurized liquefied gas is discharged from the liquefied gas outlet and recycled, improving the liquefied gas recovery efficiency and avoiding the waste of resources caused by the direct discharge of liquefied gas with the amine liquid.

[0053] Example 5

[0054] This embodiment is a micro-droplet dual-enhanced liquefied gas desulfurization method. This method can be applied in the desulfurization reactor 3 as in Embodiment 1 or Embodiment 2. The desulfurization reactor 3 has a reaction chamber formed by a liquefied gas-liquid zone 14 and an amine liquid zone 16. The interface between the upper liquefied gas-liquid zone 14 and the lower amine liquid zone 16 forms a mixed flow zone 15. The amine liquid is dispersed into amine droplets and then introduced into the liquefied gas-liquid zone 14. The angle between the tilt angle of the amine droplets when they are ejected and the vertical direction is 40-80°.

[0055] The amine droplets flow downwards and first enter the mixed flow zone 15, then flow into the amine liquid zone 16. During this process, the liquefied gas to be desulfurized is dispersed into liquefied gas droplets and then introduced into the amine liquid zone 16. The liquefied gas droplets undergo a first desulfurization mass transfer in the amine liquid zone 16 and then float upwards to the mixed flow zone 15. They collide and come into contact with the amine liquid and amine droplets in the mixed flow zone 15 to achieve a second desulfurization mass transfer. After the second desulfurization mass transfer, the liquefied gas droplets float upwards and flow into the liquefied gas liquid zone 14, where they undergo a third desulfurization mass transfer with the amine droplets in the liquefied gas liquid zone 14, thus completing the desulfurization of the liquefied gas.

[0056] The liquefied gas droplets are micron-sized droplets, while the amine droplets are millimeter-sized droplets. Due to the small size of the liquefied gas droplets and amine droplets, the contact area between the amine droplets and the liquefied gas can be increased, as can the contact area between the liquefied gas droplets and the amine liquid, thus achieving dual-enhanced desulfurization of the liquefied gas.

[0057] During the desulfurization mass transfer process, the fluid turbulence in the desulfurization mass transfer section is intense. The amine liquid droplets flow downwards and collide with the liquefied gas micro-droplets flowing upwards in the mixed flow zone 15, thus carrying out desulfurization mass transfer. The secondary desulfurization mass transfer achieved by the collision and contact improves the desulfurization effect on the liquefied gas.

[0058] Amine droplets flow downwards due to gravity, while liquefied gas droplets rise due to buoyancy. The amine liquid in amine liquid zone 16 is discharged outwards from the amine liquid outlet 13 below, and the amine liquid continuously flows downwards. The liquefied gas in liquefied gas liquid zone 14 is discharged from the liquefied gas outlet above, and the liquefied gas continuously flows upwards. Therefore, both the primary and tertiary desulfurization mass transfer in this method are countercurrent contact mass transfers, which can further enhance the desulfurization effect.

Claims

1. A micro-droplet dual-enhanced liquefied gas desulfurization reactor, the desulfurization reactor having an upper liquefied gas-liquid outlet (12) and a lower amine liquid outlet (13), characterized in that, The desulfurization reactor (3) has a lower amine liquid zone (16), an upper liquefied gas-liquid zone (14), and a mixed flow zone (15) formed at the junction of the amine liquid zone (16) and the liquefied gas-liquid zone (14). The liquefied gas-liquid zone (14) is equipped with an amine liquid nozzle (7) that can spray amine liquid droplets, and the amine liquid zone (16) is equipped with a liquefied gas-liquid nozzle (8) that can spray liquefied gas droplets. The pressure environment inside the desulfurization reactor (3) is above 1.6 MPa to keep the liquefied gas entering the desulfurization reactor (3) in a liquid phase state. The liquefied gas droplets undergo desulfurization and mass transfer in the amine liquid zone (16) and flow upward, and successively contact and react with the amine droplets in the mixed flow zone (15) and the amine droplets in the liquefied gas-liquid zone (14) to complete the desulfurization treatment of the liquefied gas. The amine spray nozzle (7) is a rotating impeller nozzle; The desulfurization reactor (3) is equipped with a packing stabilization section for separating liquefied gas and amine liquid. Multiple packing stabilization sections are provided, with at least one packing stabilization section located above the amine liquid nozzle (7) and at least one packing stabilization section located below the liquefied gas and amine liquid nozzle (8).

2. A microdroplet dual intensified liquefied gas desulfurization reactor according to claim 1, characterized in that, The packing stabilization section includes a packing cover plate (4) and a packing support plate (6) arranged laterally in the desulfurization reactor (3). The packing cover plate (4) is located above the packing support plate (6), and a material storage space is provided between the packing cover plate (4) and the packing support plate (6) to fill the packing (5).

3. The microdroplet dual-enhanced liquefied gas desulfurization reactor according to claim 2, characterized in that, The filler (5) is one or more of the following: Pall rings, step rings, rectangular saddles, and titanium nanofiber mesh.

4. A micro-droplet dual-enhanced liquefied gas desulfurization method, employing the micro-droplet dual-enhanced liquefied gas desulfurization reactor as described in claim 1, having a reaction chamber formed by a liquefied gas-liquid zone (14) and an amine liquid zone (16), wherein a mixed flow zone (15) is formed at the interface between the upper liquefied gas-liquid zone (14) and the lower amine liquid zone (16), characterized in that, After the amine liquid is dispersed into amine droplets, it is introduced into the liquefied gas-liquid zone (14). The amine droplets flow downward and first enter the mixed flow zone (15), and then flow into the amine liquid zone (16). During this process, the liquefied gas to be desulfurized is dispersed into liquefied gas droplets and then introduced into the amine liquid zone (16). The liquefied gas droplets first undergo desulfurization mass transfer in the amine liquid zone (16) and then float upward to the mixed flow zone (15). They collide and contact with the amine liquid and amine droplets in the mixed flow zone (15) to achieve secondary desulfurization mass transfer. After secondary desulfurization mass transfer, the liquefied gas droplets float upward and flow into the liquefied gas-liquid zone (14), and undergo tertiary desulfurization mass transfer with the amine droplets in the liquefied gas-liquid zone (14) to complete the desulfurization of the liquefied gas.

5. A process for desulphurization of LPG by microdroplet dual intensification as claimed in claim 4 wherein, Both primary and tertiary desulfurization mass transfer are countercurrent contact mass transfer.

6. A process for desulphurization of LPG by microdroplet dual intensification as claimed in claim 4 wherein, Amine droplets are millimeter-sized droplets, while liquefied gas droplets are micrometer-sized droplets.

7. A process for desulphurization of LPG by microdroplet dual intensification as claimed in claim 4 wherein, The angle between the tilt angle of the amine droplets when they are ejected and the vertical direction is 40° to 80°.

8. A microdroplet dual-enhanced liquefied gas desulfurization reaction system, characterized in that, The system includes a lean amine buffer tank (1), a purified liquefied gas amine separator (9), a liquefied gas deamine coalescer (10), and a desulfurization reactor (3) as described in any one of claims 1 to 3. The lean amine buffer tank (1) is connected to the amine nozzle (7) of the desulfurization reactor (3) through a lean amine delivery pipeline to deliver lean amine into the desulfurization reactor (3). The liquefied gas nozzle (8) of the desulfurization reactor (3) is connected to a liquefied gas inlet pipe to provide liquefied gas to be desulfurized into the desulfurization reactor (3). The amine outlet (13) of the desulfurization reactor (3) is connected to the inlet of the solvent regeneration device through a rich amine delivery pipeline. The liquefied gas outlet (12) of the desulfurization reactor (3) is connected to the purified liquefied gas amine separator (9) and the liquefied gas deamine coalescer (10) in sequence through pipelines.

9. The microdroplet dual intensified liquefied gas desulfurization reaction system according to claim 8, characterized in that, A liquid-liquid hydrocyclone (11) is connected to the amine liquid delivery pipeline to separate the liquefied gas in the amine liquid. The liquefied gas outlet of the liquid-liquid hydrocyclone (11) is connected to the liquefied gas inlet pipe, and the amine liquid outlet of the liquid-liquid hydrocyclone (11) is connected to the inlet of the solvent regeneration device.

10. The microdroplet dual intensified liquefied gas desulfurization reaction system according to claim 8, characterized in that, A delivery pump is connected to the lean amine solution delivery pipeline.

11. The microdroplet dual-enhanced liquefied gas desulfurization reaction system according to claim 10, characterized in that, The delivery pump is a liquefied gas desulfurization liquid pump (2).

12. The microdroplet dual intensified liquefied gas desulfurization reaction system according to claim 8, characterized in that, The outlet of the solvent regeneration device is connected to the lean amine buffer tank (1).

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