阅读说明：本技术 一种液态烃脱硫醇及脱硫醇剂再生的方法及装置 (Method and device for removing mercaptan from liquid hydrocarbon and regenerating sweetening agent ) 是由 柯明 喻武钢 童燕兵 周细殊 喻彰 梁玮 徐振华 傅海滨 于 2021-08-31 设计创作，主要内容包括：本发明公开了一种液态烃脱硫醇及脱硫醇剂再生的方法及装置,该装置包括脱硫醇液膜床壳体,所述脱硫醇液膜床壳体的下部通过法兰与脱硫醇分离罐的顶部一侧接口连接,脱硫醇液膜床纤维内芯伸入所述脱硫醇分离罐内,所述脱硫醇分离罐的顶部出口通过管线与水洗液膜床壳体的顶部入口连接,所述水洗液膜床壳体的下部通过法兰与水洗分离罐的顶部一侧接口连接,水洗液膜床纤维内芯伸入所述水洗分离罐内,所述水洗分离罐的顶部出口连接精制液态烃线。本发明的整个工艺过程,不使用磺化酞菁钴及氢氧化钠碱液,无碱渣排放,脱硫醇剂再生不使用空气或氧气,无恶臭尾气排放,液态烃脱硫醇效率高,可将液态烃中硫醇硫脱除至0.5??g·g～(-1)以下。(The invention discloses a method and a device for desulfurizing mercaptan in liquid hydrocarbon and regenerating a desulfurizing alcohol agent, wherein the device comprises a desulfurizing alcohol liquid membrane bed shell, the lower part of the desulfurizing alcohol liquid membrane bed shell is connected with an interface at one side of the top of a desulfurizing alcohol separating tank through a flange, an inner core of a fiber of the desulfurizing alcohol liquid membrane bed extends into the desulfurizing alcohol separating tank, an outlet at the top of the desulfurizing alcohol separating tank is connected with an inlet at the top of a water washing liquid membrane bed shell through a pipeline, the lower part of the water washing liquid membrane bed shell is connected with an interface at one side of the top of a water washing separating tank through a flange, the inner core of the fiber of the water washing liquid membrane bed extends into the water washing separating tank, and an outlet at the top of the water washing separating tank is connected with a refined liquid hydrocarbon line. The whole process of the invention does not use sulfonated cobalt phthalocyanine and sodium hydroxide alkali liquor, does not discharge alkali slag, and does not use air for regenerating the dealcoholization agentOr oxygen, no foul tail gas emission, high efficiency of removing mercaptan from liquid hydrocarbon, and capability of removing mercaptan sulfur from liquid hydrocarbon to 0.5 mug g ‑1 The following.)

1. The utility model provides a device that liquid hydrocarbon sweetening was taken off mercaptan and sweetening agent is regenerated, a serial communication port, including sweetening alcohol liquid membrane bed casing (1), the lower part of sweetening alcohol liquid membrane bed casing (1) is through the top one side interface connection of flange with sweetening knockout drum (3), the top export of sweetening alcohol knockout drum (3) is through the top entry linkage of pipeline and washing liquid membrane bed casing (6), the lower part of washing liquid membrane bed casing (6) is through the top one side interface connection of flange with washing knockout drum (8), the top exit linkage refined liquid hydrocarbon line (32) of washing knockout drum (8), circulation waterline (41) and waste water line (43) are connected respectively to the bottom export of washing knockout drum (8), circulation waterline (41) are connected through circulating pump (11) the upside entry of washing liquid membrane bed casing (6), the inlet of the circulating water washing pump (11) is also connected with a fresh desalting water line (42);

the bottom outlet of the sweetening separation tank (3) is connected with the upper side inlet of a sweetening agent regeneration tower (13) through a mercaptan-containing sweetening agent line (33), a sweetening agent heat exchanger (12) is arranged on the mercaptan-containing sweetening agent line (33), the bottom outlet of the sweetening agent regeneration tower (13) is respectively connected with a regenerated sweetening agent line (34) and a reboiling agent line (35), the regenerated sweetening agent line (34) is connected with the inlet of a regenerated sweetening agent pump (15), the outlet of the regenerated sweetening agent pump (15) is connected with the inlet of a sweetening agent cooler (16) through the sweetening agent heat exchanger (12), the outlet of the sweetening agent cooler (16) is connected with the upper side inlet of a sweetening agent liquid membrane bed shell (1), and the reboiling agent line (35) is connected with the lower side inlet of the sweetening agent regeneration tower (13) through a reboiler (20), the reboiler (20) still is connected with steam line (39) and condensation waterline (40), the entry of return gas cooler (17) is connected through return gas line (36) to the top export of sweetening alcohol agent regenerator (13), the export of return gas cooler (17) and the top entry linkage of return tank (18), the top exit linkage of return tank (18) contains mercaptan noncondensation gas line (37), the bottom export of return tank (18) is connected through return liquid line (38) the top side entry of sweetening alcohol agent regenerator (13), be equipped with reflux pump (19) on return liquid line (38).

2. The apparatus for liquid hydrocarbon sweetening and dealcoholizing and regeneration of the dealcoholizing agent according to claim 1, the top inlet of the desulfurization alcohol liquid film bed shell (1) is connected with a liquid hydrocarbon pipe (31), a desulfurization alcohol liquid membrane bed fiber inner core (2) is arranged in the desulfurization alcohol liquid membrane bed shell (1), the desulfurization alcohol liquid film bed fiber inner core (2) extends into the mercaptan removal separation tank (3), a mercaptan removal separation tank flow distribution plate (4) and a mercaptan removal separation tank coalescer (5) are arranged in the mercaptan removal separation tank (3), the coalescer (5) of the sweetening separation tank and the desulfurization alcohol liquid film bed shell (1) are respectively positioned at the two sides of the splitter plate (4) of the sweetening separation tank, the top outlet and the bottom outlet of the mercaptan removal separation tank (3) are both positioned on one side of the mercaptan removal separation tank coalescer (5) far away from the flow distribution plate (4) of the mercaptan removal separation tank; install washing liquid membrane bed fibre inner core (7) in washing liquid membrane bed casing (6), washing liquid membrane bed fibre inner core (7) stretch into in washing knockout drum (8), install washing knockout drum flow distribution plate (9) and washing knockout drum coalescer (10) in washing knockout drum (8), washing knockout drum coalescer (10), washing liquid membrane bed casing (6) are located respectively the both sides of washing knockout drum flow distribution plate (9), the top export and the bottom export of washing knockout drum (8) all are located washing knockout drum coalescer (10) are kept away from one side of washing knockout drum flow distribution plate (9).

3. The device for removing mercaptans and regenerating a sweetening agent by using liquid hydrocarbons as claimed in claim 2, wherein the inner core (2) of the sweetening agent liquid membrane bed fiber and the inner core (7) of the rinsing agent liquid membrane bed fiber are both hydrophilic modified fiber yarns, the base material of the hydrophilic modified fiber yarns is stainless steel, the diameter of the hydrophilic modified fiber yarns is 0.05-0.2mm, the hydrophilic angle of the hydrophilic modified fiber yarns is not more than 5 degrees, and the hydrophilic modified fiber yarns are in a continuous corrugated shape or a spiral shape.

4. The device for removing mercaptans and regenerating a sweetening agent by liquid hydrocarbon according to claim 2, wherein the flow distribution plate (4) of the sweetening separation tank and the flow distribution plate (9) of the water washing separation tank are both made of stainless steel, the flow distribution plate (4) of the sweetening separation tank and the flow distribution plate (9) of the water washing separation tank are both provided with through holes which are uniformly distributed, the aperture of each through hole gradually changes from small to large along the outward direction from the center of the flow distribution plate (4) of the sweetening separation tank and the flow distribution plate (9) of the water washing separation tank, the aperture is 10-50mm, and the boundary distance between two adjacent through holes is not more than 20 mm.

5. The device for liquid hydrocarbon sweetening and dealcoholizing agent regeneration according to claim 2, wherein the sweetening separator tank coalescer (5) and the water washing separator tank coalescer (10) each comprise a hydrophilic fiber mesh and an oleophilic fiber mesh, the hydrophilic fiber mesh is stainless steel microfilaments with hydrophilically modified surfaces, and the wetting angle of water on the surfaces of the stainless steel microfilaments is not more than 3 degrees; the oleophilic fiber filament is a blend modified fiber filament of polythioether and fluoropolymer, or a blend coating of polythioether and fluoropolymer is sprayed on the surface of the stainless steel microfilament, the longitudinal and transverse fiber filaments are welded by hot melting without adhesives, and the wetting angle of surface oil of the oleophilic fiber filament is not more than 3 degrees; the pore diameters of the hydrophilic fiber mesh and the lipophilic fiber mesh are both in the range of 5-15 μm.

6. The apparatus for liquid hydrocarbon sweetening and dealcoholizing and regeneration of the sweetening agent according to claim 1, wherein the sweetening agent regeneration tower (13) is internally welded with a tower plate (14).

7. A method for liquid hydrocarbon sweetening and sweetening agent regeneration using the apparatus of claim 1, comprising the steps of:

s1 the mercaptan-containing liquid hydrocarbon raw material flows into the device and is sent out of the device under the action of the pressure of the liquid hydrocarbon raw material at 0.2-3.0 Mpa and 10-50 ℃ at the temperature;

s2 regenerated sweetening agent enters the sweetening agent liquid film bed shell (1) from the upper side part and is uniformly distributed on the hydrophilic modified fiber yarns in the sweetening agent liquid film bed shell (1) through a liquid distributor, the sweetening agent extends on the surfaces of the hydrophilic modified fiber yarns to form micron-sized water-phase thin films, liquid hydrocarbon raw materials enter the sweetening agent liquid film bed shell (1) from the top and flow through a large number of hydrophilic modified fiber yarns in the sweetening agent liquid film bed shell (1) from top to bottom, two phases of oil agent are fully contacted in a liquid film mode, mercaptan in liquid hydrocarbon is absorbed by the sweetening agent to generate a mercaptan compound which is stable at normal temperature and is dissolved in the sweetening agent, and the oil agent automatically flows into a sweetening agent separation tank (3) for settlement separation;

before flowing to an outlet of a mercaptan removal separation tank (3), liquid hydrocarbon and a sweetening agent in the S3 sedimentation separation process are uniformly distributed on the inner cross section of the mercaptan removal separation tank (3) through a flow distribution plate (4) of the mercaptan removal separation tank in the mercaptan removal separation tank (3), and then flow out of the mercaptan removal separation tank (3) after sequentially flowing through a hydrophilic filter screen and a lipophilic filter screen of a coalescer (5) of the mercaptan removal separation tank;

s4 liquid hydrocarbon after mercaptan removal of the liquid film bed enters a washing liquid film bed shell (6) from the top and flows through a large number of hydrophilic modified fibers in the washing liquid film bed shell (6) from top to bottom, washing water enters the washing liquid film bed shell (6) from the upper side and is uniformly distributed on the hydrophilic modified fibers in the washing liquid film bed shell (6) through a liquid distributor, the water extends on the surface of the hydrophilic modified fibers to form a micron-sized water phase film, oil and water phases are in full contact, a polar desulfurization alcohol agent carried by the dissolved liquid hydrocarbon is extracted into the water, and the oil and the water automatically flow into a washing separation tank (8) for sedimentation separation;

liquid hydrocarbon and washing water in the S5 sedimentation separation process flow to the front of an outlet of a washing separation tank (8), are uniformly distributed on the inner cross section of the washing separation tank (8) through a distribution plate (9) of the washing separation tank in the washing separation tank (8), and then flow out of the washing separation tank (8) after sequentially flowing through a hydrophilic filter screen and a hydrophilic filter screen of a coalescer (10) of the separation tank;

s6 heat-exchanging the desulfurized alcohol agent after absorbing mercaptan, and then entering a desulfurized alcohol agent regeneration tower (13) from the upper side part after heat-exchanging with the regenerated desulfurized alcohol agent from the bottom of the desulfurized alcohol agent regeneration tower (13), heating the desulfurized alcohol agent containing mercaptan by a reboiler (20) connected with the bottom of the desulfurized alcohol agent regeneration tower (13), resolving the mercaptan from the desulfurized alcohol agent and forming a gas phase with trace hydrocarbons dissolved in the desulfurized alcohol agent, and sending the uncondensed gas containing the mercaptan out of a reflux tank (18) to recover sulfur; the top pressure of the sweetening agent regeneration tower (13) is controlled to be 0.06-0.15MPa, the top temperature of the sweetening agent regeneration tower (13) is controlled to be 120 ℃ at 100-.

8. The method for removing mercaptans and regenerating a sweetening agent for liquid hydrocarbons as claimed in claim 7, wherein the sweetening agent consists of a first component, a second component and water, the first component is one or a mixture of quaternary ammonium base and quaternary phosphonium base, and the first component accounts for 0.1-50% of the total weight of the sweetening agent; the second component is one or a mixture of more of monoethanolamine, diethanolamine, methyldiethanolamine, diglycolamine, diisopropanolamine, ethylenediamine, propylenediamine, butanediamine, N-formyl morpholine, N-methyl pyrrolidone, methanol, ethanol and glycol, and accounts for 0.1-98% of the total weight of the dealcoholization agent; the rest is water.

9. The method of claim 7, wherein the mass ratio of the sweetening agent to the liquid hydrocarbon entering the membrane bed is in the range of 20-40%, and the mass ratio of the washing water to the liquid hydrocarbon entering the membrane bed is in the range of 10-30%.

10. The method for recovering mercaptan removal and dealcoholization agent from liquid hydrocarbon according to claim 7, wherein the liquid hydrocarbon sweetening extraction and separation apparatus is designed to have one or more stages of liquid membrane beds and sweetening separation tanks according to the content of mercaptan in the raw liquid hydrocarbon and the desulfurization accuracy requirements of the product, or is designed to have one sweetening separation tank per stage of liquid membrane bed for series operation according to site location conditions, or two liquid membrane beds are installed on the same sweetening separation tank, and partition plates are installed in the sweetening separation tank to realize the serial or parallel use of the multistage liquid membrane beds through pipeline valve design, or one liquid membrane bed is reserved for standby use.

Technical Field

The invention relates to the technical field of petroleum refining, in particular to a method and a device for removing mercaptan from liquid hydrocarbon and regenerating a dealcoholization agent.

Background

At present, the process for refining liquefied petroleum gas, light components of carbon three, carbon four, carbon five, gasoline or naphtha and other liquid hydrocarbons by removing mercaptan from liquefied petroleum gas, light components of gasoline or naphtha, which are produced by petrochemical enterprises at home and abroad, generally adopts a sodium hydroxide alkali liquor extraction process, mercaptan in the liquid hydrocarbons is transferred into alkali liquor in a sodium mercaptan form, then air is introduced into the alkali liquor for catalytic oxidation in an oxidation tower, sodium mercaptan is oxidized to generate disulfide and sodium hydroxide, then the disulfide and the sodium hydroxide are removed through the sedimentation of a disulfide separating tank, the reverse extraction of solvent oil or the bubbling of air or nitrogen with large air volume, and regenerated alkali liquor is recycled for extracting and removing mercaptan from the liquid hydrocarbons.

The regeneration quality of the desulfurized alcohol alkali liquor (especially the content of sodium mercaptide and disulfide in the regenerated alkali liquor) plays a decisive role in refining the total sulfur of the liquid hydrocarbon, and the oxidized regeneration effect of the desulfurized alcohol alkali liquor of some devices is not ideal, and the desulfurized alcohol alkali liquor can be made up by periodically replacing the alkali liquor. In addition, after long-term use of the alkali liquor of the liquid hydrocarbon sweetening device system, due to consumption of reaction between carbon dioxide in air for oxidation and sodium hydroxide, consumption of sodium sulfide which cannot be regenerated back to sodium hydroxide after oxidation, consumption of reaction between acidic substances in solvent oil and sodium hydroxide, pollution of substances such as mechanical impurities in liquefied gas and solvent oil, corrosion and rust pollution of carbon steel equipment and pipelines, the concentration of sodium hydroxide in the alkali liquor of the system is gradually reduced, the content of pollution impurities is increased, the sweetening effect of the alkali liquor of the system is reduced, the viscosity is increased, and especially, the discharge amount of waste alkali liquor of the liquid hydrocarbon sweetening device is increased even seriously because hydrogen sulfide of some liquefied gas amine sweetening devices is not completely removed or amine liquid is seriously carried. According to statistics, taking a 50 ten thousand tons/year catalytic liquefied gas sweetening device as an example, a conventional MEROX liquid hydrocarbon sweetening device is adopted, the amount of waste alkali liquor discharged per year is up to 600-; taking a 10 ten thousand tons/year coking liquefied gas sweetening device as an example, a conventional MEROX liquid hydrocarbon sweetening device is adopted, the amount of waste alkali liquor discharged per year is up to 1500-3000 tons, and a fiber membrane contactor is adopted to wash alkali to remove mercaptan and a device for removing disulfide by reverse extraction of solvent oil, and the amount of waste alkali liquor discharged per year is still 200-300 tons. In addition, a large amount of stink tail gas containing disulfide is generated by oxidizing and regenerating the desulfurized alcohol alkali liquor, and the stink tail gas can be discharged after being burnt or treated by the stink tail gas.

Along with the increasing importance of the society on the environmental protection problem, the problem that the waste alkali liquor discharged by liquid hydrocarbon sweetening is difficult to treat is more and more prominent, and the significance of developing a liquid hydrocarbon sweetening process without waste alkali liquor discharge by non-alkali liquor sweetening is larger and larger.

Patent 200710071004.9 relates to an oxidative regeneration method of liquefied gas desulfurized alcohol alkali liquor.

Patent 200910250279.8 relates to a technology for removing mercaptans from liquid hydrocarbons, which can remove total sulfur deeply, and the technology improves the extraction efficiency by adding an auxiliary agent into the extracted alkaline solution in the traditional liquid hydrocarbon extraction and alkaline solution oxidation processes, and enhances the three-phase mixing degree of alkaline solution oxidation and solvent reverse extraction.

Patent 201220012653.8 relates to a combined system for liquefied gas sweetening, the liquefied gas sweetening part adopts the liquid membrane reactor described in patent 201520069733.0 to wash out mercaptans, and the sweetening alkali liquor is regenerated by the alkali liquor microbubble oxidation, coalescence separation recovery and gas stripping disulfide removal technologies described in patent 200710308071.8.

Patent 201210276509.X relates to a method for removing mercaptans from gasoline light fractions and regenerating alkali liquor.

Patent 201220253818.0 relates to a catalytic liquefied gas deep mercaptan removal device, which adopts a three-stage fiber liquid membrane reactor to wash and remove mercaptan.

Patent 201520069733.0 relates to a method for desulfurizing liquefied gas by absorbing and removing hydrogen sulfide and removing mercaptan with alkali liquor in an amine liquid of a liquid membrane reactor.

Patent 00129724.4 proposes a method in which mercaptan in liquefied gas is converted into disulfide, the disulfide is removed by distillation, and the mixture of disulfide and liquefied gas heavy components is rectified and purified.

Patent 01134688.4 relates to a method for industrially refining liquefied gas, in which mercaptan is converted into disulfide by passing the liquefied gas through a desulfurizing agent and a catalyst in a fixed bed reactor, and the disulfide is removed from the liquefied gas by further rectification, thereby achieving the purpose of desulfurization.

Patent 201410218896.0 relates to a method for refining liquefied gas, which comprises hydrolyzing carbonyl sulfide to obtain hydrogen sulfide with solid carbonyl sulfide hydrolysis catalyst, absorbing the hydrogen sulfide with alcohol amine solution, etherifying mercaptan and olefin with thioetherification catalyst to obtain disulfide with high boiling point, and separating liquefied gas and disulfide with distillation tower to remove carbonyl sulfide and mercaptan.

Patent 201010562902.6 relates to a sweetening agent composition, patent 201010562891.1 relates to a refining method of liquefied gas, the liquefied gas after decarbonylation and desulphurization is extracted and removed mercaptan by an extraction tower and a sweetening agent, the sweetening agent absorbing mercaptan is removed by a stripping technology and regenerated, the sweetening agent is recycled, and the liquefied gas after extraction and desulphurization is eluted by a mixer and a settling tank to remove the entrained sweetening agent.

Patent 201420514825.0, patent 201410454906.0 and patent 201520325634.4 relate to methods for oil sweetening and alkali liquor oxidation regeneration.

Disclosure of Invention

In view of the above technical problems in the related art, the present invention provides a method and an apparatus for sweetening liquid hydrocarbons and regenerating a sweetening agent, which can overcome the above disadvantages of the prior art.

In order to achieve the technical purpose, the technical scheme of the invention is realized as follows:

a device for removing mercaptan from liquid hydrocarbon and regenerating a sweetening agent comprises a sweetening agent liquid membrane bed shell, wherein the lower portion of the sweetening agent liquid membrane bed shell is connected with an interface on one side of the top of a sweetening agent separation tank through a flange, an outlet on the top of the sweetening agent separation tank is connected with an inlet on the top of a washing liquid membrane bed shell through a pipeline, the lower portion of the washing liquid membrane bed shell is connected with an interface on one side of the top of a washing separation tank through a flange, an outlet on the top of the washing separation tank is connected with a refined liquid hydrocarbon line, outlets on the bottom of the washing separation tank are respectively connected with a circulating water line and a waste water line, the circulating water line is connected with an inlet on the upper side of the washing liquid membrane bed shell through a circulating water washing pump, and an inlet of the circulating water washing pump is further connected with a fresh desalting water line;

the bottom outlet of the sweetening separation tank is connected with the upper side inlet of a sweetening agent regeneration tower through a sweetening agent line containing mercaptan, a sweetening agent heat exchanger is arranged on the sweetening agent line containing mercaptan, the bottom outlet of the sweetening agent regeneration tower is respectively connected with a regenerated sweetening agent line and a reboiling agent line, the regenerated sweetening agent line is connected with the inlet of a regenerated sweetening agent pump, the outlet of the regenerated sweetening agent pump is connected with the inlet of a sweetening agent cooler through the sweetening agent heat exchanger, the outlet of the sweetening agent cooler is connected with the upper side inlet of a sweetening agent liquid membrane bed shell, the reboiling agent line is connected with the lower side inlet of the sweetening agent regeneration tower through a reboiler, the steam line and a condensation waterline are further connected, and the top outlet of the sweetening agent regeneration tower is connected with the inlet of a reflux gas cooler through a reflux gas line, the export of backward flow gas cooler and the top entry linkage of reflux drum, the top exit linkage of reflux drum contains the not gas line that condenses of mercaptan, the bottom export of reflux drum passes through the reflux liquid line and connects the top side entry of sweetening agent regeneration tower, be equipped with the backwash pump on the reflux liquid line.

Further, a top inlet of the desulfurized alcohol liquid membrane bed shell is connected with a liquid hydrocarbon pipe, a desulfurized alcohol liquid membrane bed fiber inner core is installed in the desulfurized alcohol liquid membrane bed shell, the desulfurized alcohol liquid membrane bed fiber inner core extends into the sweetening separation tank, a sweetening separation tank flow distribution plate and a sweetening separation tank coalescer are installed in the sweetening separation tank, the sweetening separation tank coalescer and the desulfurized alcohol liquid membrane bed shell are respectively positioned on two sides of the sweetening separation tank flow distribution plate, and a top outlet and a bottom outlet of the sweetening separation tank are both positioned on one side, away from the sweetening separation tank flow distribution plate, of the sweetening separation tank coalescer; install washing liquid membrane bed fibre inner core in the washing liquid membrane bed casing, washing liquid membrane bed fibre inner core stretches into in the washing knockout drum, install washing knockout drum flow distribution plate and washing knockout drum coalescer in the washing knockout drum, washing knockout drum coalescer, washing liquid membrane bed casing are located respectively the both sides of washing knockout drum flow distribution plate, the top export and the bottom export of washing knockout drum all are located washing knockout drum coalescer is kept away from one side of washing knockout drum flow distribution plate.

Further, the desulfurization alcohol solution membrane bed fiber inner core and the rinsing liquid membrane bed fiber inner core are hydrophilic modified fiber yarns, the base material of the hydrophilic modified fiber yarns is stainless steel, the diameter of the hydrophilic modified fiber yarns is 0.05-0.2mm, the hydrophilic angle of the hydrophilic modified fiber yarns is not more than 5 degrees, and the hydrophilic modified fiber yarns are in a continuous corrugated shape or a spiral shape.

Further, it is stainless steel to take off mercaptan knockout drum flow distribution plate and washing knockout drum flow distribution plate, all be equipped with evenly distributed's through-hole on taking off mercaptan knockout drum flow distribution plate and the washing knockout drum flow distribution plate, the aperture of through-hole is followed respectively take off mercaptan knockout drum flow distribution plate, washing knockout drum flow distribution plate from the outside direction in center from little to big gradual change, the aperture is 10-50mm, and adjacent two through-hole border distance is no longer than 20 mm.

Furthermore, the mercaptan removal separation tank coalescer and the water washing separation tank coalescer respectively comprise a hydrophilic fiber screen and an oleophilic fiber screen, the hydrophilic fiber screen is a stainless steel microfilament with the surface modified by hydrophilicity, and the wetting angle of water on the surface of the stainless steel microfilament is not more than 3 degrees; the oleophilic fiber filament is a blend modified fiber filament of polythioether and fluoropolymer, or a blend coating of polythioether and fluoropolymer is sprayed on the surface of the stainless steel microfilament, the longitudinal and transverse fiber filaments are welded by hot melting without adhesives, and the wetting angle of surface oil of the oleophilic fiber filament is not more than 3 degrees; the pore diameters of the hydrophilic fiber mesh and the lipophilic fiber mesh are both in the range of 5-15 μm.

Furthermore, a tower plate is welded in the sweetening agent regeneration tower.

According to another aspect of the present invention, there is provided a method for the sweetening of liquid hydrocarbons and the regeneration of a sweetening agent, the method comprising the steps of:

s1 the mercaptan-containing liquid hydrocarbon raw material flows into the device and is sent out of the device under the action of the pressure of the liquid hydrocarbon raw material at 0.2-3.0 Mpa and 10-50 ℃ at the temperature;

s2 the regenerated sweetening agent enters the sweetening agent liquid film bed shell 1 from the upper side and is evenly distributed on the hydrophilic modified fiber yarns in the sweetening agent liquid film bed shell 1 through the liquid distributor, the sweetening agent extends on the surface of the hydrophilic modified fiber yarns to form a micron-sized water phase film, the liquid hydrocarbon raw material enters the sweetening agent liquid film bed shell 1 from the top and flows through a large number of hydrophilic modified fiber yarns in the sweetening agent liquid film bed shell 1 from top to bottom, two phases of the oil agent are fully contacted in a liquid film mode, mercaptan in the liquid hydrocarbon is absorbed by the sweetening agent to generate a mercaptan compound which is stable at normal temperature and is dissolved in the sweetening agent, and the oil agent automatically flows into the sweetening agent separation tank 3 for settlement separation;

before flowing to the outlet of the mercaptan removal separation tank 3, the liquid hydrocarbon and the dealcoholization agent in the S3 sedimentation separation process are uniformly distributed on the inner cross section of the mercaptan removal separation tank 3 through a flow distribution plate 4 of the mercaptan removal separation tank 3, and then flow out of the mercaptan removal separation tank 3 after sequentially flowing through a hydrophilic filter screen and a lipophilic filter screen of a coalescer 5 of the mercaptan removal separation tank;

s4 the liquid hydrocarbon after mercaptan removal of the liquid film bed enters the washing liquid film bed shell 6 from the top and flows through the space between a large number of hydrophilic modified fiber yarns in the washing liquid film bed shell 6 from top to bottom, washing water enters the washing liquid film bed shell 6 from the upper side and is uniformly distributed on the hydrophilic modified fiber yarns in the washing liquid film bed shell 6 through a liquid distributor, the water extends on the surface of the hydrophilic modified fiber yarns to form a micron-sized water phase film, oil and water are in full contact with each other, the polar desulfurization alcohol agent carried by the dissolved liquid hydrocarbon is extracted into the water, and the oil and the water automatically flow into the washing separation tank 8 for sedimentation separation;

s5 before the liquid hydrocarbon and the washing water flow to the outlet of the washing separation tank 8 in the sedimentation separation process, the liquid hydrocarbon and the washing water flow through the diversion plate 9 of the washing separation tank 8 and are uniformly distributed on the inner cross section of the washing separation tank 8, and then flow through the hydrophilic filter screen and the hydrophilic filter screen of the coalescer 10 in sequence and flow out of the washing separation tank 8;

s6 heat-exchanging the desulfurized alcohol agent after absorbing mercaptan, entering the desulfurized alcohol agent regeneration tower 13 from the upper side after heat-exchanging with the regenerated desulfurized alcohol agent from the bottom of the desulfurized alcohol agent regeneration tower 13, heating the desulfurized alcohol agent containing mercaptan by a reboiler 20 connected with the bottom of the desulfurized alcohol agent regeneration tower 13, resolving the mercaptan from the desulfurized alcohol agent and forming a gas phase with the trace hydrocarbons dissolved in the desulfurized alcohol agent, and sending the uncondensed gas containing the mercaptan out of the reflux tank 18 to recover sulfur; the top pressure of the sweetening agent regeneration tower 13 is controlled to be 0.06-0.15MPa, the top temperature of the sweetening agent regeneration tower 13 is controlled to be 100-120 ℃, the bottom temperature of the sweetening agent regeneration tower 13 is controlled to be 110-130 ℃, the top reflux ratio of the sweetening agent regeneration tower 13 is adjusted, the sulfur content of the regenerated sweetening agent is controlled not to exceed 0.1g/L, and the regenerated sweetening agent is pressurized by a regenerated sweetening agent pump 15 and then sent to liquid hydrocarbon for cyclic sweetening after passing through a sweetening agent heat exchanger 12 and cyclic cooling.

Further, the alcohol desulfurization agent consists of a first component, a second component and water, wherein the first component is one or a mixture of more of quaternary ammonium base and quaternary phosphonium base, and accounts for 0.1-50% of the total weight of the alcohol desulfurization agent; the second component is one or a mixture of more of monoethanolamine, diethanolamine, methyldiethanolamine, diglycolamine, diisopropanolamine, ethylenediamine, propylenediamine, butanediamine, N-formyl morpholine, N-methyl pyrrolidone, methanol, ethanol and glycol, and accounts for 0.1-98% of the total weight of the dealcoholization agent; the rest is water.

Furthermore, the mass ratio of the sweetening agent to the liquid hydrocarbon in the liquid inlet film bed is 20-40%, and the mass ratio of the washing water to the liquid hydrocarbon in the liquid inlet film bed is 10-30%.

Furthermore, the equipment for extracting and separating the liquid hydrocarbon by removing the mercaptan can be designed into one or more stages of liquid membrane beds and mercaptan removal separating tanks according to the content of the mercaptan in the raw material liquid hydrocarbon and the desulfurization precision requirement of the product, and can also be designed into one mercaptan removal separating tank for each stage of liquid membrane bed according to the situation of site position, and the two liquid membrane beds are connected in series or are arranged on the same mercaptan removal separating tank, partition plates are arranged in the mercaptan removal separating tanks, and the multistage liquid membrane beds are used in series or in parallel through the design of pipeline valves, or one liquid membrane bed is reserved for standby.

The invention has the beneficial effects that: the invention aims at solving the problem that the waste alkali liquor discharged by the existing alkali washing mercaptan removal process is difficult to treat, a sweetening agent composition is adopted, mercaptan in liquid hydrocarbon is removed by combining with a liquid membrane bed efficient mass transfer device, the sweetening agent is recycled through steam heating regeneration, non-condensable gas containing mercaptan in the regeneration process is sent to a sulphur recovery device to produce sulphur, the whole process does not use sulfonated cobalt phthalocyanine and sodium hydroxide solution, no caustic sludge is discharged, air or oxygen is not used in the sweetening agent regeneration, no odor tail gas is discharged, and the sweetening efficiency of the liquid hydrocarbon is high. Aiming at the desulfurization precision requirements of raw material liquid hydrocarbon and products with different mercaptan contents, the desulfurization alcohol liquid membrane bed can be designed into a single stage or multiple stages, the first-stage liquid membrane bed is designed for washing and removing the desulfurization alcohol agent, the mass flow of the desulfurization alcohol agent is 20-40% of the mass flow of the liquid hydrocarbon, the mass flow of the washing water is 10-30% of the mass flow of the liquid hydrocarbon, and the desulfurization alcohol sulfur in the liquid hydrocarbon can be removed to 0.5 mu g^-1The regeneration energy consumption of the sweetening agent is reduced at the same time. The mercaptan-removing separating tank and the water washing tank are internally provided with a plurality of layers of hydrophilic filter screens and lipophilic filter screen coalescers, so that the mercaptan-removing separating tank and the water washing tank can greatly reduceThe liquid hydrocarbon is carried with the sweetening agent and the water after little extraction, thereby greatly reducing the discharge of the desalted water and the waste water for washing.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings without creative efforts.

FIG. 1 is a flow chart of an exemplary process for an apparatus for the non-alkaline sweetening and desulfurizing agent regeneration of liquid hydrocarbons according to an embodiment of the present invention;

FIG. 2 is a process flow diagram for mercaptan removal using a two-stage liquid membrane bed and a separation tank according to an embodiment of the present invention;

FIG. 3 is a schematic diagram of an apparatus for removing mercaptans by using two liquid membrane beds and sharing a separation tank according to an embodiment of the invention;

FIG. 4 is a schematic view of a splitter plate within a separator tank according to an embodiment of the present invention (laser drilled at all the intersections of the dashed lines);

FIG. 5 is a schematic illustration of a coalescer in a separator tank according to an embodiment of the invention;

in the figure: 1. a sweetening alcohol liquid film bed shell, 2 a sweetening alcohol liquid film bed fiber inner core, 3 a sweetening separation tank, 4 a sweetening separation tank splitter plate, 5 a sweetening separation tank coalescer, 6 a water washing liquid film bed shell, 7 a water washing liquid film bed fiber inner core, 8 a water washing separation tank, 9 a water washing separation tank splitter plate, 10 a water washing separation tank coalescer, 11 a circulating water washing pump, 12 a sweetening agent heat exchanger, 13 a sweetening agent regeneration tower, 14 a column plate, 15 a regenerated sweetening agent pump, 16 a sweetening agent cooler, 17 a reflux gas cooler, 18 a reflux tank, 19 a reflux pump, 20, 31, a liquid hydrocarbon pipe, 32, a refined liquid hydrocarbon line, 33 a sweetening alcohol-containing sweetening agent line, 34, a sweetening agent line, 35, a reboiling agent line, 36 a reflux gas line, 37 a non-condensing gas line containing mercaptan, 38, a reflux liquid line, 39 a reflux liquid line, Steam line, 40, condensation waterline, 41, circulation waterline, 42, fresh desalination waterline, 43, waste water line.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments that can be derived by one of ordinary skill in the art from the embodiments given herein are intended to be within the scope of the present invention.

Example 1

Referring to fig. 1, an apparatus for removing mercaptans and regenerating a sweetening agent from liquid hydrocarbons according to an embodiment of the invention comprises a sweetening agent liquid membrane bed shell 1, the lower part of the desulfurization alcohol liquid film bed shell 1 is connected with an interface at one side of the top of the desulfurization alcohol separation tank 3 through a flange, the top outlet of the mercaptan removal separation tank 3 is connected with the top inlet of a water washing liquid membrane bed shell 6 through a pipeline, the lower part of the washing liquid membrane bed shell 6 is connected with an interface at one side of the top of the washing separating tank 8 through a flange, the top outlet of the water washing separation tank 8 is connected with a refined liquid hydrocarbon line 32, the bottom outlet of the water washing separation tank 8 is respectively connected with a circulating water line 41 and a waste water line 43, the circulating water line 41 is connected with an inlet at the upper side part of the washing liquid membrane bed shell 6 through a circulating water washing pump 11, and an inlet of the circulating water washing pump 11 is also connected with a fresh desalting water line 42;

the bottom outlet of the mercaptan removal separation tank 3 is connected with the upper inlet of a sweetening agent regeneration tower 13 through a mercaptan-containing sweetening agent line 33, a sweetening agent heat exchanger 12 is arranged on the mercaptan-containing sweetening agent line 33, the bottom outlet of the sweetening agent regeneration tower 13 is respectively connected with a regenerated sweetening agent line 34 and a reboiling agent line 35, the regenerated sweetening agent line 34 is connected with the inlet of a regenerated sweetening agent pump 15, the outlet of the regenerated sweetening agent pump 15 is connected with the inlet of a sweetening agent cooler 16 through the sweetening agent heat exchanger 12, the outlet of the sweetening agent cooler 16 is connected with the upper inlet of a reboiler membrane bed shell 1, the reboiling agent line 35 is connected with the lower inlet of the sweetening agent regeneration tower 13 through a reboiler 20, the reboiler 20 is further connected with a steam line 39 and a condensation water line 40, the top outlet of the sweetening agent regeneration tower 13 is connected with the inlet of a reflux gas cooler 17 through a reflux gas line 36, the outlet of the reflux gas cooler 17 is connected with the top inlet of the reflux tank 18, the top outlet of the reflux tank 18 is connected with a mercaptan-containing noncondensable gas line 37, the bottom outlet of the reflux tank 18 is connected with the top inlet of the sweetening agent regeneration tower 13 through a reflux liquid line 38, and the reflux liquid line 38 is provided with a reflux pump 19.

The desulfurization alcohol liquid membrane bed comprises a desulfurization alcohol liquid membrane bed shell 1, a liquid hydrocarbon pipe 31, a desulfurization alcohol liquid membrane bed fiber inner core 2, a desulfurization alcohol separation tank 3, a desulfurization alcohol separation tank splitter plate 4 and a desulfurization alcohol separation tank coalescer 5, wherein the desulfurization alcohol liquid membrane bed fiber inner core 2 is arranged in the desulfurization alcohol liquid membrane bed shell 1, the desulfurization alcohol separation tank 3 is internally provided with the desulfurization alcohol separation tank splitter plate 4 and the desulfurization alcohol separation tank coalescer 5, the desulfurization alcohol separation tank coalescer 5 and the desulfurization alcohol liquid membrane bed shell 1 are respectively positioned at two sides of the desulfurization alcohol separation tank splitter plate 4, and a top outlet and a bottom outlet of the desulfurization alcohol separation tank 3 are both positioned at one side, far away from the desulfurization alcohol separation tank splitter plate 4, of the desulfurization alcohol separation tank coalescer 5; install washing liquid membrane bed fibre inner core 7 in washing liquid membrane bed casing 6, washing liquid membrane bed fibre inner core 7 stretches into in the washing knockout drum 8, install washing knockout drum flow distribution plate 9 and washing knockout drum coalescer 10 in the washing knockout drum 8, washing knockout drum coalescer 10, washing liquid membrane bed casing 6 are located respectively washing knockout drum flow distribution plate 9's both sides, washing knockout drum 8's top export and bottom export all are located washing knockout drum coalescer 10 keeps away from one side of washing knockout drum flow distribution plate 9.

The desulfurization alcohol liquid membrane bed fiber inner core 2 and the rinsing liquid membrane bed fiber inner core 7 are hydrophilic modified fiber yarns, the base material of the hydrophilic modified fiber yarns is stainless steel, the diameter of the hydrophilic modified fiber yarns is 0.05-0.2mm, the surface of the hydrophilic modified fiber yarns is treated by a hydrophilic modification technology, the hydrophilic angle of the hydrophilic modified fiber yarns is not more than 5 degrees, and the hydrophilic modified fiber yarns are in a continuous corrugated shape or a spiral shape.

As shown in fig. 4, it is stainless steel to take off mercaptan knockout drum flow distribution plate 4 and washing knockout drum flow distribution plate 9, all be equipped with evenly distributed's through-hole on taking off mercaptan knockout drum flow distribution plate 4 and the washing knockout drum flow distribution plate 9, the aperture of through-hole is followed respectively take off mercaptan knockout drum flow distribution plate 4, washing knockout drum flow distribution plate 9 from the outside direction in center from little to big gradual change, the aperture is 10-50mm, and adjacent two through-hole border distance is no longer than 20mm, and the material passes through take off mercaptan knockout drum flow distribution plate 4, washing knockout drum flow distribution plate 9 pressure drop all do not exceed 0.1 kPa.

As shown in fig. 5, the mercaptan removal separation tank coalescer 5 and the water washing separation tank coalescer 10 both comprise a hydrophilic fiber screen and an oleophilic fiber screen, the hydrophilic fiber screen is a stainless steel microfilament with a surface modified by hydrophilicity, and the wetting angle of water on the surface of the stainless steel microfilament is not more than 3 degrees; the oleophilic fiber filament is a blend modified fiber filament of polythioether and fluoropolymer, or a blend coating of polythioether and fluoropolymer is sprayed on the surface of the stainless steel microfilament, the longitudinal and transverse fiber filaments are welded by hot melting without adhesives, and the wetting angle of surface oil of the oleophilic fiber filament is not more than 3 degrees; the pore diameters of the hydrophilic fiber screen and the lipophilic fiber screen are both in the range of 5-15 μm, and the pressure drop of the materials passing through the mercaptan removal separation tank coalescer 5 and the water washing separation tank coalescer 10 is not more than 1 kPa.

A tower plate 14 is welded in the sweetening agent regeneration tower 13.

The method for removing mercaptan from liquid hydrocarbon and regenerating the dealcoholization agent by adopting the device comprises the following steps:

s1 the mercaptan-containing liquid hydrocarbon raw material flows into the device and is sent out of the device under the action of the pressure of the liquid hydrocarbon raw material at 0.2-3.0 Mpa and 10-50 ℃ at the temperature;

s2 the regenerated sweetening agent enters the sweetening agent liquid film bed shell 1 from the upper side and is evenly distributed on the hydrophilic modified fiber yarns in the sweetening agent liquid film bed shell 1 through the liquid distributor, the sweetening agent extends on the surface of the hydrophilic modified fiber yarns to form a micron-sized water phase film, the liquid hydrocarbon raw material enters the sweetening agent liquid film bed shell 1 from the top and flows through a large number of hydrophilic modified fiber yarns in the sweetening agent liquid film bed shell 1 from top to bottom, two phases of the oil agent are fully contacted in a liquid film mode, mercaptan in the liquid hydrocarbon is absorbed by the sweetening agent to generate a mercaptan compound which is stable at normal temperature and is dissolved in the sweetening agent, and the oil agent automatically flows into the sweetening agent separation tank 3 for settlement separation; the structured liquid film bed has been used in patent 202010646623.1.

Before the liquid hydrocarbon and the desulfurization alcohol agent flow to the outlet of the mercaptan removal separation tank 3 in the S3 sedimentation separation process, the liquid hydrocarbon and the desulfurization alcohol agent are uniformly distributed on the inner cross section of the mercaptan removal separation tank 3 through a flow distribution plate 4 of the mercaptan removal separation tank 3, then sequentially flow through a hydrophilic filter screen and a lipophilic filter screen of a coalescer 5 of the mercaptan removal separation tank and then flow out of the mercaptan removal separation tank 3, and the entrainment of free aqueous phase substances in the liquid hydrocarbon discharged from the mercaptan removal separation tank 3 is not more than 10 [ mu ] g^-1The entrainment of oil phase substances in the mercaptan removal agent is not more than 100 mug/g^-1；

S4 the liquid hydrocarbon after mercaptan removal of the liquid film bed enters the washing liquid film bed shell 6 from the top and flows through the space between a large number of hydrophilic modified fiber yarns in the washing liquid film bed shell 6 from top to bottom, washing water enters the washing liquid film bed shell 6 from the upper side and is uniformly distributed on the hydrophilic modified fiber yarns in the washing liquid film bed shell 6 through a liquid distributor, the water extends on the surface of the hydrophilic modified fiber yarns to form a micron-sized water phase film, oil and water are in full contact with each other, the polar desulfurization alcohol agent carried by the dissolved liquid hydrocarbon is extracted into the water, and the oil and the water automatically flow into the washing separation tank 8 for sedimentation separation;

before liquid hydrocarbon and washing water in the S5 sedimentation separation process flow to the outlet of the washing separation tank 8, the liquid hydrocarbon and the washing water are uniformly distributed on the inner cross section of the washing separation tank 8 through the diversion plate 9 of the washing separation tank in the washing separation tank 8, then sequentially flow through the hydrophilic filter screen and the hydrophilic filter screen of the coalescer 10 and then flow out of the washing separation tank 8, and the entrainment of free water in the liquid hydrocarbon out of the washing separation tank 8 is not more than 10 [ mu ] g & g [ ]^-1The entrainment of oil phase substances in the discharged wastewater is not more than 100 mug/g^-1Mercaptan in the liquid hydrocarbon after the first-stage liquid membrane bed is washed by water is removed by the first-stage or multi-stage liquid membrane bed sweetening agent^-1The following;

s6 heat-exchanging the desulfurized alcohol agent after absorbing mercaptan, entering the desulfurized alcohol agent regeneration tower 13 from the upper side after heat-exchanging with the regenerated desulfurized alcohol agent from the bottom of the desulfurized alcohol agent regeneration tower 13, heating the desulfurized alcohol agent containing mercaptan by a reboiler 20 connected with the bottom of the desulfurized alcohol agent regeneration tower 13, resolving the mercaptan from the desulfurized alcohol agent and forming a gas phase with the trace hydrocarbons dissolved in the desulfurized alcohol agent, and sending the uncondensed gas containing the mercaptan out of the reflux tank 18 to recover sulfur; the top pressure of the sweetening agent regeneration tower 13 is controlled to be 0.06-0.15MPa, the top temperature of the sweetening agent regeneration tower 13 is controlled to be 100-120 ℃, the bottom temperature of the sweetening agent regeneration tower 13 is controlled to be 110-130 ℃, the top reflux ratio of the sweetening agent regeneration tower 13 is adjusted, the sulfur content of the regenerated sweetening agent is controlled not to exceed 0.1g/L, and the regenerated sweetening agent is pressurized by a regenerated sweetening agent pump 15 and then sent to liquid hydrocarbon for cyclic sweetening after passing through a sweetening agent heat exchanger 12 and cyclic cooling.

The regeneration energy consumption of the sweetening agent is reduced by more than 50 percent compared with the sweetening process of the extraction tower.

The alcohol desulfurization agent consists of a first component, a second component and water, wherein the first component is one or a mixture of more of quaternary ammonium base and quaternary phosphonium base, and accounts for 0.1-50% of the total weight of the alcohol desulfurization agent; the second component is one or a mixture of more of monoethanolamine, diethanolamine, methyldiethanolamine, diglycolamine, diisopropanolamine, ethylenediamine, propylenediamine, butanediamine, N-formyl morpholine, N-methyl pyrrolidone, methanol, ethanol and glycol, and accounts for 0.1-98% of the total weight of the dealcoholization agent; the rest is water.

The mass ratio of the sweetening agent to the liquid hydrocarbon of the liquid inlet film bed is 20-40%, and the mass ratio of the water washing water to the liquid hydrocarbon of the liquid inlet film bed is 10-30%;

as shown in fig. 2-3, the liquid hydrocarbon sweetening extraction and separation apparatus may be designed with one or more stages of liquid membrane beds and sweetening separation tanks according to the content of mercaptans in the raw liquid hydrocarbon and the requirement of the product sweetening accuracy, or may be designed with one sweetening separation tank for each stage of liquid membrane bed according to the site location, and operated in series, or two liquid membrane beds are installed on the same sweetening separation tank, and a partition is installed in the sweetening separation tank, and the multistage liquid membrane beds are used in series or in parallel through the design of pipeline valves, or one liquid membrane bed is reserved for standby, so that the liquid hydrocarbon sweetening apparatus is operated without shutdown for a long period, and the liquid hydrocarbon membrane bed is conveniently cleaned.

Example 2

The catalytic liquefied gas after the hydrogen sulfide is eluted by amine has the temperature of 38 ℃, the pressure of 3.0MPa and the mercaptan content of 189 microgram-g^-1And the content of carbonyl sulfur is 3 mug/g, primary liquid film bed sweetening agent extraction and primary liquid film bed washing are carried out by adopting the device for sweetening liquid hydrocarbon and regenerating the sweetening agent in the embodiment 1, the mass flow of the sweetening agent and the washing water is 20-25% of the mass flow of the liquefied gas, the operation pressure of the top of the sweetening agent regeneration tower is 0.08MPa, the temperature of the top of the tower is 109 ℃, the temperature of the bottom of the tower is 122 ℃, and the content of refined liquefied gas mercaptan is 0.1 mug/g^-10.2 mug/g of carbonyl sulfide content and 9 mug/g of free water carried by the carbonyl sulfide^-1And carrying 18 mug/g of oil phase substances in the discharged wastewater.

Example 3

Coking liquefied gas after hydrogen sulfide elution by amine has the temperature of 35 ℃, the pressure of 2.3MPa and the mercaptan content of 2800 microgram g-g^-1And the carbonyl sulfur content is 36 mug/g, a device shown in figure 2 is adopted to carry out two-stage liquid film bed sweetening agent extraction and one-stage liquid film bed water washing, the mass flow of the sweetening agent is 35-40% of the mass flow of the liquefied gas, the mass flow of the water washing is 25-30% of the mass flow of the liquefied gas, the operation pressure of the top of the sweetening agent regeneration tower is 0.09MPa, the temperature of the top of the tower is 112 ℃, the temperature of the bottom of the tower is 125 ℃, and the refined liquefied gas mercaptan content is 0.5 mug/g^-1The content of carbonyl sulfur is 0.5 mug/g, and the content of free water is less than 8 mug.g^-135 microgram-g carried by oil phase substances in discharged wastewater^-1。

Example 4

The method comprises the steps of mixing liquefied gas of catalysis and coking after hydrogen sulfide is eluted by amine, wherein the temperature is 35 ℃, the pressure is 1.1MPa, and the content of mercaptan is 565 microgram g^-1And the carbonyl sulfur content is 6.5 mug/g, the device shown in figure 2 is adopted to carry out two-stage liquid film bed sweetening alcohol agent extraction and one-stage liquid film bed water washing, the mass flow of the sweetening alcohol agent is 20-25% of the mass flow of the liquefied gas, the mass flow of the water washing is 10-15% of the mass flow of the liquefied gas, the operation pressure of the regeneration tower top of the sweetening alcohol agent is 0.06MPa, the tower top temperature is 107 ℃, the tower bottom temperature is 123 ℃, and the refined liquefied gas mercaptan content is 0.2 mug g^-1The content of carbonyl sulfur is 0.3 mug/g, and the content of free water is less than 8 mug.g^-133 microgram-g carried by oil phase substances in discharged wastewater^-1。

Example 5

Performing primary liquid film bed sweetening alcohol agent extraction and primary liquid film bed water washing by adopting the device for sweetening liquid hydrocarbon and regenerating the sweetening alcohol agent in the embodiment 1, wherein the sweetening agent dosage flow is 20-25% of the mass flow of the liquefied gas, the water washing mass flow is 10-15% of the mass flow of the liquefied gas, the operation pressure of a sweetening alcohol agent regeneration tower is 0.15MPa, the tower top temperature is 120 ℃, the tower bottom temperature is 130 ℃, and the content of refined liquefied gas mercaptan is less than 0.3 mug.g^-1The content of carbonyl sulfur is 0.2 mug/g, and the content of free water is less than 6 mug.g^-128 mug-g carried by oil phase substances in discharged wastewater^-1。

Example 6

Catalyzing light components of gasoline, wherein the distillation range is 35-80 ℃, the temperature is 40 ℃, the pressure is 0.2MPa, and the mercaptan content is 128 mug g^-1Performing primary liquid film bed sweetening agent extraction and primary liquid film bed washing by using the device for sweetening liquid hydrocarbons and regenerating the sweetening agent in embodiment 1, wherein the sweetening agent is 25-30% of the mass flow of the catalytic light gasoline, the mass flow of the washing water is 20-25% of the mass flow of the liquefied gas, the operation pressure of the top of the sweetening agent regeneration tower is 0.1MPa, the temperature of the top of the tower is 115 ℃, the temperature of the bottom of the tower is 127 ℃, and the content of the refined liquefied gas mercaptan is less than 0.4 mu g-g^-1Free water entrainment less than 9 microgram g^-1The entrainment of oil phase substances in the discharged wastewater is not more than 42 mug/g^-1。

In summary, by means of the technical scheme of the invention, the mercaptan sulfur in the liquid hydrocarbon is removed by combining a sweetening agent composition with a liquid membrane bed extraction technology for the liquid hydrocarbon such as liquefied gas containing mercaptan organic sulfur (including catalytic cracking liquefied gas, coking liquefied gas and the like), carbon three, carbon four, carbon five, light components of gasoline or naphtha, and the like, the liquid hydrocarbon can achieve the purpose of deep desulfurization, the sweetening agent-rich composition can be regenerated by heating and recycled, and the non-condensable gas containing mercaptan in the regeneration process is sent to a sulfur recovery device to produce sulfur. The whole process does not use sulfonated cobalt phthalocyanine and sodium hydroxide solution, does not discharge alkali slag, and does not regenerate the dealcoholization agentWith air or oxygen, no foul tail gas is discharged, aiming at the requirements of desulfurization precision of liquid hydrocarbon and products of raw materials with different mercaptan contents, the desulfurization alcohol liquid membrane bed can be designed into a single-stage or multi-stage mode, only the water washing desulfurization alcohol agent is designed into a first-stage liquid membrane bed, and the desulfurization alcohol sulfur in the liquid hydrocarbon can be removed to 0.5 mu g.g^-1Meanwhile, the flow of the sweetening agent is reduced by more than 50 percent compared with the sweetening process of the extraction tower, the regeneration energy consumption of the sweetening agent can be greatly reduced, the hydrocarbon entrainment of refined liquid hydrocarbon and the hydrocarbon entrainment of water washing discharge wastewater are obviously reduced, and the process technology belongs to an environment-friendly process.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.