Bubble tower reactor

Abstract

The present invention provides a bubble column reactor, comprising a lower chamber formed in the lower part, a reaction zone formed in the upper part of the lower chamber, a dispersion plate formed between the lower chamber and the reaction zone, and a gas supply pipe connected to the lower chamber to supply gaseous reactants, wherein the gas supply pipe includes an injection section extending into the lower chamber, wherein the injection section includes a plurality of nozzles that inject gaseous reactants onto the lower side of the lower chamber.

Description

[0001] Cross-references to related applications

[0002] This application claims priority to Korean Patent Application No. 10-2021-0162827, filed on November 23, 2021, the entire contents of which are incorporated herein by reference for all purposes. Technical Field

[0003] This invention relates to a bubble column reactor, and more specifically, to a bubble column reactor in which oligomers are prepared, wherein the bubble column reactor is used to improve the mixing efficiency of the reaction medium by uniformly supplying gaseous reactants to the reaction zone. Background Technology

[0004] Alpha-olefins are widely used commercially as important materials in comonomers, detergents, lubricants, and plasticizers. In particular, 1-hexene and 1-octene have been widely used as comonomers to control the density of polyethylene in the production of linear low-density polyethylene (LLDPE).

[0005] α-olefins are typically prepared by the oligomerization of ethylene. As a type of reactor in which the oligomerization of ethylene takes place, a bubble column reactor has been used to carry out the oligomerization (trimerization or tetramerization) of ethylene by contacting gaseous ethylene as a reactant with a reaction zone containing a liquid reaction medium containing a catalyst.

[0006] In a bubble column reactor, gaseous reactants are supplied to the lower chamber located at the bottom of the reactor, introduced into the reaction zone containing liquid reaction media, and simultaneously dispersed and mixed by a dispersion plate.

[0007] In related technologies, when supplying gaseous reactants to the lower chamber via a gas supply pipe, the method employed is to spray them upwards toward a dispersion plate in the lower chamber. However, in this case, it is difficult for the gaseous reactants to pass through the dispersion plate in a sufficiently mixed state within the lower chamber due to the injection pressure. Furthermore, due to problems such as various byproducts generated from the oligomerization reaction in the reaction zone clogging the pores of the dispersion plate, there are limitations to uniformly supplying gaseous reactants solely through the dispersion plate. This leads to a reduction in the mixing efficiency between the reaction medium and the gaseous reactants in the reaction zone.

[0008] Therefore, in order to solve the above problems, it is necessary to study the uniform dispersion and supply of gaseous reactants to the reaction zone. Summary of the Invention

[0009] [Technical Issues]

[0010] In order to solve the problems mentioned in the background art of the present invention, the object of the present invention is to provide a bubble column reactor in which gaseous reactants in the lower chamber are sufficiently and uniformly dispersed before being supplied to the reaction zone.

[0011] [Technical Solution]

[0012] In one general aspect, the bubble column reactor includes: a lower chamber formed in the lower part; a reaction zone formed in the upper part of the lower chamber; a dispersion plate formed between the lower chamber and the reaction zone; and a gas supply pipe connected to the lower chamber to supply gaseous reactants, wherein the gas supply pipe includes an injection section extending into the lower chamber, and the injection section includes a plurality of nozzles that inject the gaseous reactants onto the lower side of the lower chamber.

[0013] [Beneficial Effects]

[0014] According to the bubble column reactor of the present invention, by injecting gaseous reactants into the lower side of the lower chamber through an injection section extending from the gas supply pipe into the lower chamber, a path and time can be provided for the gaseous reactants to be fully mixed in the lower chamber, and the gaseous reactants can be uniformly supplied to the reaction zone and mixed with the reaction medium.

[0015] Furthermore, by setting the injection direction and injection angle differently according to the position of the nozzle of the injection unit, uniform mixing of the injected gaseous reactants can be achieved, thereby uniformly supplying gaseous reactants in the reaction zone and maximizing the mixing efficiency of the reaction zone. Attached Figure Description

[0016] Figure 1 This is a flowchart of a bubble column reactor and related processes according to one embodiment of the present invention.

[0017] Figure 2 This is an enlarged view of a portion of a bubble column reactor according to one embodiment of the present invention.

[0018] Figure 3 This is an enlarged view of a portion of a bubble column reactor according to another embodiment of the present invention.

[0019] Figure 4 It is a flowchart of the bubble column reactor and related processes based on relevant technologies. Detailed Implementation

[0020] The terms and words used in the specification and claims of this invention should not be interpreted as having a general or dictionary meaning, but rather should be interpreted as having a meaning and concept consistent with the technical idea of ​​this invention, based on the principle that the inventors can appropriately define the concepts of the terms in order to best describe their own invention.

[0021] In this invention, the term "flow" can refer to the flow of fluid in a process, or to the fluid itself flowing through a delivery pipeline (pipeline). Specifically, "flow" can refer to both the fluid itself flowing through pipes connecting various devices and the flow of fluid. Furthermore, fluid can refer to one or more of gas, liquid, and solid.

[0022] In this invention, the term "C#" where "#" is a positive integer refers to all hydrocarbons having # carbon atoms. Therefore, the term "C10" refers to a hydrocarbon compound having 10 carbon atoms. Furthermore, the term "C#+" refers to all hydrocarbon molecules having # or more carbon atoms. Therefore, the term "C10+" refers to a mixture of hydrocarbons having 10 or more carbon atoms.

[0023] In the following text, reference will be made to Figure 1 The invention will be described in more detail to aid in understanding it.

[0024] According to the present invention, a bubble column reactor 100 is provided. The bubble column reactor 100 includes a lower chamber 200 formed in the lower part, a reaction zone 300 formed in the upper part of the lower chamber 200, a dispersion plate 350 formed between the lower chamber and the reaction zone, and a gas supply pipe 210 connected to the lower chamber to supply gaseous reactants, wherein the gas supply pipe 210 includes an injection section 220 extending into the lower chamber 200, and the injection section 220 includes a plurality of nozzles 230 for injecting gaseous reactants into the lower side of the lower chamber 200.

[0025] According to one embodiment of the present invention, the bubble column reactor 100 can be used to prepare oligomer products by oligomerizing monomers in the presence of a catalyst and a solvent.

[0026] More specifically, the bubble column reactor 100 may include a reaction zone 300, and a reaction medium may be supplied to the reaction zone 300 via one or more reaction medium supply lines 310 connected to one side of the reaction zone 300.

[0027] Meanwhile, the reaction medium may include a catalyst, a co-catalyst, and a solvent. The catalyst, co-catalyst, and solvent may be supplied separately through a separate reaction medium supply line 310, and two or more reaction medium components may be mixed and supplied to the reaction zone 300 through the reaction medium supply line 310.

[0028] According to one embodiment of the invention, the monomer may include ethylene monomer. As a specific example, a gaseous reactant including ethylene monomer may be supplied to the lower chamber 200 of a bubble column reactor 100, which will be described later, to produce the desired α-olefin product by oligomerization.

[0029] Solvents may include one or more selected from n-pentane, n-hexane, n-heptane, cyclohexane, methylcyclohexane, octane, cyclooctane, decane, dodecane, benzene, xylene, 1,3,5-trimethylbenzene, toluene, ethylbenzene, chlorobenzene, dichlorobenzene, and trichlorobenzene.

[0030] The catalyst may include a transition metal source. The transition metal source may be one or more compounds selected from, for example, chromium acetylacetonate (III), chromium tetrahydrofuran chloride (III), chromium 2-ethylhexanoate (III), chromium tri(2,2,6,6-tetramethyl-3,5-heptadecanoate (III), chromium benzoylacetone (III), chromium hexafluoro-2,4-pentanedione (III), chromium acetate (III) hydroxide, chromium acetate (III), chromium butyrate (III), chromium valerate (III), chromium laurate (III), and chromium stearate (III).

[0031] The cocatalyst may include one or more selected from, for example, trimethylaluminum, triethylaluminum, triisopropylaluminum, triisobutylaluminum, ethyl sesquichloride, diethylaluminum chloride, ethyl dialuminum chloride, methylaluminoxane, modified methylaluminoxane, and borate.

[0032] Meanwhile, in the reaction zone 300 of the bubble column reactor 100, the oligomerization reaction of the monomer can be carried out in a liquid reaction medium including a catalyst, a co-catalyst, and a solvent. As described above, the region consisting of the reaction medium in which the oligomerization reaction of the monomer takes place can be defined as the reaction zone 300. Oligomerization can refer to the reaction in which monomers are oligomerized. Depending on the number of monomers to be polymerized, oligomerization reactions can also be called trimerization and tetramerization, which are collectively referred to as polymerization.

[0033] Alpha-olefins are widely used commercially as important materials in comonomers, detergents, lubricants, plasticizers, and more. In particular, 1-hexene and 1-octene are commonly used as comonomers to control the density of polyethylene in the production of linear low-density polyethylene (LLDPE). Alpha-olefins, such as 1-hexene and 1-octene, can be prepared by trimerizing or tetramerizing, for example, ethylene.

[0034] The bubble column reactor 100 may include a product discharge line 320 connected to the reaction zone 300 and disposed on the other side of the reaction medium supply line, through which products including the oligomerization product α-olefin may be discharged. Supplying the reaction medium to the reaction zone 300 and discharging products from the reaction zone 300 can be continuous.

[0035] Meanwhile, gaseous reactants containing monomers for oligomerization can be supplied to the lower chamber 200 located at the bottom of the bubble column reactor 100, and then supplied to the reaction zone 300 containing liquid reaction media via the dispersion plate 350.

[0036] In other words, the dispersion plate 350 can be disposed between the lower chamber 200 and the reaction zone 300. Gaseous reactants, such as monomers, can be uniformly distributed from the lower chamber 200 through holes formed at equal intervals along the center and circumference of the dispersion plate 350 and supplied to the reaction zone 300, which includes the reaction medium.

[0037] Gaseous reactants flow into the reaction zone 300 containing the liquid reaction medium through the dispersion plate 350 and are simultaneously dispersed. Turbulence is generated by the force of the dispersed gas, causing the liquid reaction medium and gaseous reactants to mix naturally. At this time, the dispersion force of the gaseous reactants flowing into the reaction zone 300 through the dispersion plate 350 remains greater than the head pressure acting downwards from the liquid reaction medium, allowing the liquid reaction medium to remain in the reaction zone 300.

[0038] According to one embodiment of the present invention, gaseous reactants can be supplied into the lower chamber 200 via a gas supply pipe 210 connected to and supplying gaseous reactants. The gas supply pipe 210 may include a plurality of nozzles 230, each nozzle 230 having an injection portion 220 extending into the lower chamber 200 and injecting the gaseous reactants onto the lower side of the lower chamber 200. The nozzles 230 can control the injection direction and angle of the gaseous reactants to be injected, and as a device for applying a constant injection pressure, there are no particular limitations on the form and structure of the nozzles 230.

[0039] In other words, during the process of supplying a gaseous reactant, such as gaseous ethylene, to the lower chamber 200, the gaseous reactant is injected downwards and supplied to the lower surface of the lower chamber 200, causing the injected gaseous reactant stream to collide with the sidewall or lower surface of the lower chamber 200 and be altered, and may cause the gaseous reactant to move towards the sidewall of the lower chamber 200. (Similar to...) Figure 4 Compared to the case where gaseous reactants are sprayed upward toward the dispersion plate in the related art shown, this can reduce the central concentration of the gaseous reactants during their upward movement. That is, in the present invention, the gaseous reactants, which are in a state of uniform mixing in the lower chamber 200, can pass through the dispersion plate 350, thereby improving the mixing efficiency of the reaction zone 300, and furthermore, causing a uniform reaction throughout the reaction zone to improve the conversion rate.

[0040] Reference Figure 2 and Figure 3 The gas supply pipe 210 and the injection section 220 can be configured as an integrated pipe. Simultaneously, the injection section 220 can extend from the gas supply pipe 210 into the interior of the lower chamber 200 in the horizontal direction of its horizontal cross-section. That is, the injection section 220 can extend horizontally through the center of the horizontal cross-section of the lower chamber 200. Furthermore, multiple nozzles disposed in the injection section 220 can be arranged in a row in the radial direction of the lower chamber (i.e., the extension direction of the injection section 220).

[0041] Furthermore, depending on their location, the multiple nozzles can have different spray directions and different spray angles.

[0042] That is, according to one embodiment of the present invention, the plurality of nozzles may include a first nozzle located in the central region of the lower chamber 200, a second nozzle located in the region adjacent to the inner wall of the lower chamber 200, and a third nozzle located in the region between the central region and the region adjacent to the inner wall of the lower chamber 200.

[0043] Specifically, the first nozzle can be the nozzle closest to the center of the horizontal cross-section of the lower chamber or the nozzle located at the center of the horizontal cross-section, and the second nozzle can be the nozzle closest to the inner wall of the lower chamber. The third nozzle can be the nozzle located between the first and second nozzles.

[0044] More specifically, refer to Figure 2 When the number of nozzles provided in the spray section 220 is odd, the first nozzle 260 can be provided at the intersection of the central axis C of the lower chamber 200 and the spray section 220. At the same time, a second nozzle 240 can be provided adjacent to the inner wall of the lower chamber 200, and a third nozzle 250 can be provided between the first and second nozzles.

[0045] At this point, the injection direction of the first and third nozzles 250 and 260 is a downward vertical direction, and the angle between the injection direction of the second nozzle 240 and the downward vertical direction can be from 15° to 50°. Here, the injection direction refers to the direction of the nozzle outlet, with the central axis of the nozzle pointing in that direction. That is, the injection direction of the first and third nozzles 250 and 260 is towards the lower surface of the lower chamber 200, while the second nozzle 240 has an injection direction inclined towards the adjacent inner wall. This prevents the gaseous reactants from stagnating at the point where the inner wall and lower surface of the lower chamber 200 meet by strong injection, and causes a smoother flow of the gaseous reactants, thereby maximizing the mixing efficiency.

[0046] According to one embodiment of the invention, the plurality of nozzles may have different injection angles depending on their positions. Here, the injection angle refers to the angle formed by the region surrounding the gaseous reactant discharged from the nozzle outlet. In this case, the injection angle of the first nozzle 260 may be 95° to 120°, the injection angle of the second nozzle 240 may be 15° to 45°, and the injection angle of the third nozzle 250 may be 50° to 90°. When injecting the gaseous reactant, the first nozzle 260 located in the central region of the lower chamber 200 injects with a relatively wide injection angle, while the second nozzle 240 adjacent to the sidewall of the lower chamber 200 can inject with a narrower injection angle. Simultaneously, the third nozzle 250 located between the first and second nozzles can inject with an injection angle narrower than that of the first nozzle 260 and wider than that of the second nozzle 240. When the flow rates of the gaseous reactant discharged through the plurality of nozzles are the same or similar, the injection pressure of the second nozzle 240 with a narrow injection angle may be the highest compared to the first nozzle 260 with a wide injection angle.

[0047] Thus, the mixing of the gaseous reactants is further activated by the flow of the gaseous reactants injected through the plurality of nozzles, which promotes mutual mixing, and by the formation of vortices induced by the collisions of the gaseous reactants with the lower and inner surfaces of the lower chamber 200. Most importantly, the central concentration of the gaseous reactants during upward movement is reduced by injecting them at a narrow injection angle through the second nozzle 240 adjacent to the inner wall.

[0048] At the same time, refer to Figure 3 When the number of nozzles provided in the spray section 220 is even, the first nozzles 260 can be spaced apart from each other based on the central axis C of the lower chamber 200 as the center, so as to correspond to each other. At the same time, a second nozzle 240 can be provided adjacent to the inner wall of the lower chamber 200, and a third nozzle 250 can be provided between the first and second nozzles. Even when the number of the multiple nozzles is even, the spray direction and spray angle of the first to third nozzles can be the same as when the number of the multiple nozzles is odd.

[0049] Reference Figure 2 In a bubble column reactor 100 according to one embodiment of the present invention, the height H of the lower chamber 200 can be two times or more the reactor diameter R, and particularly, the height H can be two to three times the reactor diameter R. Here, the height H of the lower chamber 200 is the length from the lower surface of the lower chamber 200 to the dispersion plate 350. Figure 4Compared to the bubble column reactor 100' of the related technology shown, the height H of the lower chamber 200 is increased to more than twice the reactor diameter R, thereby ensuring sufficient upward space for the gaseous reactants after they are injected into the lower chamber 200 and improving the dispersion efficiency of the gaseous reactants. At the same time, by setting the height H of the lower chamber 200 to three times or less the reactor diameter R, the size of the bubble column reactor can be prevented from being excessively increased for the sake of dispersion efficiency.

[0050] Furthermore, the height h of the injection section 220 to the height H of the lower chamber 200, h / H, can be 0.1 to 0.5, particularly 0.2 to 0.3. If the height ratio h / H is less than 0.1, the injection section 220 may be too close to the lower surface of the lower chamber 200, thus failing to achieve the desired mixing efficiency by changing the injection direction and angle of the nozzle, and the flow of the injected gas may be negatively affected. Conversely, if the height ratio h / H is greater than 0.5, the injection section 220 may be excessively spaced from the lower surface of the lower chamber 200, and the injected gas may switch to an upward flow instead of contacting the lower surface of the lower chamber 200, resulting in reduced mixing efficiency.

[0051] Simultaneously, as the gaseous reactants supplied to the reaction zone 300 of the bubble column reactor 100 pass through the liquid reaction medium containing the solvent and catalyst, an oligomerization reaction occurs via catalytic reaction. In this case, the gaseous reactants and the reaction medium in the reaction zone 300 are mixed together, existing as a two-phase mixture. The oligomer products generated by the oligomerization reaction of the reactants can be discharged as liquid product effluents through product discharge line 320. The first gaseous effluent, including unreacted monomers that have not undergone oligomerization in the reaction medium and the solvent, can be moved to the separation zone 400 above the reaction zone 300.

[0052] Specifically, in reactor 100, due to the catalytic reaction of the monomers, solid polymers are generated as byproducts in addition to the desired oligomer products and float in the liquid reaction medium. At this time, when a large amount of gaseous reactants, including monomers, are supplied to reaction zone 300 through dispersion plate 350, the solid polymers and liquid solvents may be entrained along with the unreacted gaseous monomers and discharged as the first effluent stream.

[0053] As the first effluent stream passes through the separation zone 400, its upward velocity is reduced, and any entrained polymers and solvents can be easily removed from the first effluent stream.

[0054] Simultaneously, the first effluent stream passing through separation zone 400 can be introduced into condensation zone 500 located above separation zone 400. The solvent condensed in condensation zone 500 can be returned to the reaction zone of the reactor through separation zone 400 for reuse in the oligomerization reaction. Meanwhile, uncondensed gaseous components can be discharged to the outside of bubble column reactor 100 through gas discharge line 520.

[0055] Furthermore, the product effluent stream may include oligomer products and solvents generated through the oligomerization reaction, and the oligomer products and solvents may be separated by an additional separation device. The separated solvents can be reused during the oligomer manufacturing process. Additionally, for example, when ethylene monomer is used as the monomer for the oligomerization reaction, the oligomer products may include 1-hexene and 1-octene.

[0056] The bubble column reactor according to the present invention has been described above and illustrated in the accompanying drawings. However, the description and illustrations are only for understanding the essential components of the invention, and processes and equipment not separately described and illustrated in the specification and drawings may be suitably applied and used to implement the bubble column reactor according to the present invention.

Claims

1. A bubble column reactor, comprising: The lower chamber is formed in the lower part; A reaction zone is formed in the upper part of the lower chamber; A dispersion plate is formed between the lower chamber and the reaction zone; and A gas supply pipe, connected to the lower chamber, supplies gaseous reactants. The gas supply pipe includes a jet section extending into the lower chamber. The injection unit includes multiple nozzles that inject gaseous reactants into the lower side of the lower chamber. The plurality of nozzles include: The first nozzle is located in the central region of the lower chamber; The second nozzle is located in the region adjacent to the inner wall of the lower chamber; and The third nozzle is located in the area between the central region of the lower chamber and the region adjacent to the inner wall. The first and third nozzles spray in a downward vertical direction, and The angle between the spray direction of the second nozzle and the downward vertical direction is 15° to 50°.

2. The bubble column reactor according to claim 1, wherein, The multiple nozzles of the injection section are arranged in a row in the radial direction of the lower chamber.

3. The bubble column reactor according to claim 1, wherein, The jet extends horizontally through the center of the horizontal cross-section of the lower chamber.

4. The bubble column reactor according to claim 1, wherein, The height of the lower chamber is twice or more the diameter of the reactor.

5. The bubble column reactor according to claim 1, wherein, The multiple nozzles have different spray angles depending on their positions.

6. The bubble column reactor according to claim 5, wherein, The spray angle of the first nozzle is 95° to 120°. The second nozzle has a spray angle of 15° to 45°, and The spray angle of the third nozzle is 50° to 90°.

7. The bubble column reactor of claim 1, further comprising one or more reaction medium supply lines connected to the reaction zone, wherein, The reaction medium includes a catalyst, a co-catalyst, and a solvent.

8. The bubble column reactor according to claim 7, further comprising a product discharge line connected to the reaction zone and disposed on the other side of the reaction medium supply line.

9. The bubble column reactor according to claim 1, wherein, The gaseous reactants include ethylene.

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