Three-phase separator and fluidized bed reactor comprising three-phase separator

Abstract

The present invention relates to a three-phase separator and a fluidized bed reactor (100) comprising the three-phase separator. The three-phase separator comprises: an outer housing (101); a central flow guide cylinder (11); an external flow guide cylinder (2), which is arranged on the radial outside of the central flow guide cylinder (11); an upper sealing baffle (4), which radially extends between the central flow guide cylinder (11) and the external flow guide cylinder (2) and is connected to a top end of the central flow guide cylinder (11) and a top end of the external flow guide cylinder (2) in a sealing manner; an overflow guide cylinder (3), which is arranged between the central flow guide cylinder (11) and the external flow guide cylinder (2), wherein a gap is formed between a top end of the overflow guide cylinder (3) and the upper sealing baffle (4); a lower sealing baffle (63), which radially extends between the external flow guide cylinder (2) and the overflow guide cylinder (3) and is connected to a bottom end of the external flow guide cylinder (2) and the bottom of the overflow guide cylinder (3) in a sealing manner; and a liquid outlet pipe (7).

Description

Three-phase separator and ebullating bed reactor including the same Technical Field

[0001] The present invention relates to the technical field of gas-liquid-solid three-phase separation, and more particularly to a gas-liquid-solid three-phase separator and an ebullating bed reactor comprising the three-phase separator. Background Art

[0002] An ebullated bed reactor typically requires a gas-liquid-solid three-phase separator in the upper chamber of the reactor. In the ebullated bed, the liquid phase is the continuous phase, while the gas phase bubbles through the reactor, driven by gas, and the solid phase is the dispersed phase. Ebullated bed reactors typically have an online catalyst addition and removal system. During operation, the reactor's pressure drop is relatively stable, making it particularly suitable for hydrotreating low-quality residual oil. The raw residual oil contains a high content of impurities, resulting in a highly exothermic reaction and rapid catalyst deactivation. The catalyst is replaced regularly online, and the solid phase is circulated within the reactor via a three-phase separator, thereby maintaining a stable reaction system and enabling extended operation.

[0003] For example, Chinese patent application CN101376092A discloses an ebullating bed reactor comprising a cylindrical reactor shell perpendicular to the ground, a three-phase separator in the upper space within the reactor shell, and a guide structure. The three-phase separator consists of concentric inner and outer cylinders of different inner diameters, along with the inner wall of the reactor shell. The inner cylinder forms the center tube of the three-phase separator, while the annular space between the outer cylinder and the inner wall of the reactor shell serves as a collection area for the clean liquid product.

[0004] The three-phase separator of the prior art is provided with two annular cylinders in the upper space within the reactor shell. As shown in Figure 1, the gas-liquid-solid mixture moves upward within the annular inner cylinder and completes gas phase separation at the upper gas-liquid interface; thereafter, the liquid-solid mixed fluid flows radially outward into the area between the annular outer cylinder and the annular inner cylinder and moves downward. In the area below the annular outer cylinder, due to the density difference between the solid and the liquid, the solid and the liquid are separated and flow out of the separator and return to the main reaction zone; the remaining liquid, under the action of the "U"-shaped tube principle, moves upward in the annular space between the annular outer cylinder and the side wall of the reactor shell and flows out of the reactor through the outlet pipe. In other words, a gas phase outlet is provided at the top of the reactor, the liquid overflows out of the reactor through the side outlet pipe, and the solid catalyst flows out of the separator under the action of the density difference, achieving three-phase separation. This three-phase separator is called a sequential built-in three-phase separator.

[0005] However, this sequential built-in three-phase separator of the prior art still has a certain amount of gas phase inflow at the position of the liquid-solid deflection (between the annular outer cylinder and the reactor shell), and the bubble tail vortex effect will cause disorder in the catalyst particles, affecting the solid-liquid separation effect. Millimeter-level bubbles rise faster, while hundred-micron-level bubbles rise slower and will be affected by larger bubbles to move disorderly in the radial direction. At present, the fluidized bed reactor is basically composed of millimeter-level bubbles. In order to reduce the impact of bubbles entering in the vertical direction on separation and prevent gas from rising, a guide structure is added to the straight-cylinder reactor, or the inner diameter of the reactor is expanded at the position of the built-in separator, that is, an expanded sequential built-in three-phase separator is adopted. The guide structure is an annular protrusion structure arranged on the inner wall of the reactor shell, and the guide structure has a trapezoidal or arched shape in the longitudinal section along the axis of the reactor. The guide structure can make the gas phase rise vertically and avoid the liquid-solid deflection area as much as possible, which can reduce the amount of catalyst carried out to a certain extent, but the liquid-solid separation still cannot avoid the influence of the upward gas, and this structural design is relatively complex and the investment is high.

[0006] Therefore, there is a need for a gas-liquid-solid three-phase separator and an ebullated bed reactor including the separator, so as to effectively avoid the influence of rising gas on the liquid-solid separation efficiency.

[0007] The information disclosed in this background technology section is only intended to enhance understanding of the overall background of the invention and should not be regarded as an admission or any form of suggestion that the information constitutes the prior art already known to a person skilled in the art.

[0008] Summary of the Invention

[0009] The purpose of the present invention is to provide a three-phase separator and an ebullated bed reactor using the separator. Through the structural design of the paperclip-type reverse-sequence built-in three-phase separator, the influence of upward gas on the liquid-solid separation efficiency can be effectively avoided.

[0010] To achieve the above-mentioned object, according to a first aspect of the present invention, there is provided a three-phase separator, which is arranged in a fluidized bed reactor and is used for gas-liquid-solid three-phase separation, comprising: an outer shell; a central draft tube, which is arranged in the outer shell and is configured to receive gas, liquid and solid materials; an outer draft tube, which is arranged radially outside the central draft tube; an upper sealing baffle, which radially extends between the central draft tube and the outer draft tube and is sealingly connected to the top end of the central draft tube and the top end of the outer draft tube. an overflow guide tube, the overflow guide tube being arranged between the central guide tube and the outer guide tube, and a gap being formed between the top end of the overflow guide tube and the upper sealing baffle; a lower sealing baffle, the lower sealing baffle extending radially between the outer guide tube and the overflow guide tube and being sealingly connected to the bottom end of the outer guide tube and the bottom of the overflow guide tube; and a liquid outlet pipe, the liquid outlet pipe extending radially outward from the bottom of the outer guide tube above the lower sealing baffle to the outside of the outer shell, and being configured to discharge the separated liquid.

[0011] According to a further example of the present invention, the upper sealing baffle is arranged to be inclined downward in a radially outward direction relative to a vertical center axis of the outer shell.

[0012] According to a further example of the present invention, the three-phase separator further includes an annular bubble baffle extending obliquely downward from the bottom end of the central draft tube in a radially outward direction relative to the vertical central axis of the outer shell.

[0013] According to a further example of the present invention, the three-phase separator further includes a liquid baffle, which extends obliquely downward from the inner wall of the outer guide tube in a certain circumferential range directly above the liquid outlet pipe toward a direction away from the liquid outlet pipe.

[0014] According to a further example of the present invention, the three-phase separator also includes a guide buffer baffle, which is arranged at the bottom of the third annular space between the overflow guide tube and the central guide tube, immediately below the liquid outlet pipe, and is arranged to be inclined downward from the far side away from the liquid outlet pipe toward the liquid outlet pipe.

[0015] According to a further example of the present invention, the guide buffer baffle is provided with a plurality of holes, and the plurality of holes are connected to the annular inflation space fluid defined between the guide buffer baffle and the lower sealing baffle. The three-phase separator also includes an inflation pipe, which extends radially outward from the outer guide cylinder to the outside of the outer shell and is connected to the annular inflation space fluid, and is configured to guide gas into the annular inflation space, so that bubbles generated at the holes form turbulence for the liquid phase material on the guide buffer baffle.

[0016] According to a further example of the present invention, the flow guide buffer baffle is inclined at an angle between 5° and 20° relative to a horizontal plane perpendicular to the vertical center axis of the outer shell.

[0017] According to a further example of the present invention, the three-phase separator further includes an exhaust pipe extending upward from the upper sealing baffle near the central guide tube to above the liquid level of the three-phase separator.

[0018] According to a further example of the present invention, a plurality of exhaust pipes are arranged in a circular array around a vertical center axis of the outer housing.

[0019] According to another aspect of the present invention, an ebullated bed reactor is provided, comprising: a reactor shell and the three-phase separator, wherein the three-phase separator is arranged at the upper part of the ebullated bed reactor, and the outer shell of the three-phase separator is part of the reactor shell.

[0020] According to a further example of the present invention, the reactor shell includes: a straight cylindrical portion, an upper head and a lower head, a gas outlet is provided at the center of the upper head, and a feed inlet is provided at the center of the lower head.

[0021] According to a further example of the present invention, the ebullated bed reactor further includes a gas-liquid distributor, and the gas-liquid distributor is disposed in the lower space of the reactor shell.

[0022] According to a further example of the present invention, the upper end cap is provided with a solid catalyst particle filling port; the lower end cap is provided with a solid catalyst particle discharge port.

[0023] According to a further example of the present invention, the fluidized bed reactor also includes a guide portion arranged below the annular bubble baffle of the three-phase separator and circumferentially arranged around the inner wall of the reactor shell, and the guide portion cooperates with the annular bubble baffle to prevent bubbles in the gas, liquid and solid materials from entering the first annular space between the external guide tube and the reactor shell.

[0024] According to a further example of the present invention, the guide portion includes an annular baffle extending obliquely downward from an inner wall of the reactor housing in a radially inward direction relative to a vertical center axis of the outer housing.

[0025] According to the present invention, gas, liquid and solid materials move upward along the central flow area defined by the central guide tube, gas phase separation occurs at the liquid surface above the central guide tube, and the separated gas is discharged through the gas outlet. The liquid-solid mixture undergoes a first deflection in the first deflection area above the top of the central guide tube, enters the first annular space (also called the liquid-solid descending area) between the outer guide tube and the outer shell along the upper surface of the upper sealing baffle, and moves downward along the first annular space. The liquid-solid mixture undergoes a second deflection in the second deflection area below the lower sealing baffle. Due to the density difference between the liquid and the solid, the liquid-solid mixture undergoes liquid-solid separation below the outer guide tube. The separated solid catalyst particles leave the three-phase separator and return to the solid catalyst particle bed. The liquid and a small amount of entrained solid catalyst particles enter the second annular space (also called the overflow area) between the outer guide tube and the overflow guide tube along the lower surface of the lower sealing baffle, and move upward along the second annular space. The liquid is deflected a third time in the third deflection zone above the top of the overflow guide tube. It then passes through the gap between the top of the overflow guide tube and the upper sealing baffle, flows along the lower surface of the upper sealing baffle, and enters the third annular space (also known as the liquid outflow zone) between the central guide tube and the overflow guide tube. The liquid then travels downward along the third annular space. As the liquid collides with the lower surface of the upper sealing baffle, any unseparated solids are further separated.

[0026] According to the present invention, the liquid entering the third annular space is blocked by the liquid baffle to avoid being discharged directly from the liquid outlet pipe. Instead, it is guided by the liquid baffle to the far side of the guide buffer baffle away from the liquid outlet pipe. The liquid flows downward from the far side away from the liquid outlet pipe toward the liquid outlet pipe and is discharged evenly from the liquid outlet pipe.

[0027] According to the present invention, the inflation pipe can periodically or continuously guide gas into the annular inflation space between the guide buffer baffle and the lower sealing baffle, so that the bubbles generated at the hole form turbulence for the liquid material on the guide buffer baffle to prevent solid residue from being deposited on the guide buffer baffle.

[0028] According to the present invention, the guide portion adopts an annular baffle, which extends downwardly and obliquely from the inner wall of the reactor shell relative to the vertical center axis of the outer shell in a radially inward direction, so that bubbles accumulate in the space between the annular baffle and the side wall of the reactor shell and form large bubble cavities, forming a contact state between the gas film and the liquid film, thereby reducing the wear on the solid catalyst particles.

[0029] Compared with the prior art, the present invention has the following beneficial effects:

[0030] 1) The present invention realizes the "reverse" material flow direction (i.e., paper clip flow direction) through the structural design of "three-tube socket", so that the material moving upward along the central guide tube is directly diverted to the first annular space between the outer guide tube and the side wall of the reactor shell, thereby increasing the radial stroke of the first diversion relative to the "sequential" material flow direction of the prior art. The liquid-solid mixture undergoes a second diversion in the second diversion area below the lower sealing baffle, and enters the second annular space between the outer guide tube and the overflow guide tube along the lower surface of the lower sealing baffle, thereby increasing the radial stroke of the second diversion. In addition, it is not easy for gas to rise in the liquid-solid separation area. In addition, since the present invention adopts a "reverse" material flow direction, even if some bubbles rise from the gap between the annular bubble baffle and the outer shell, since their rising direction is opposite to the flow direction of the liquid outflow area, it is not easy to cause the solid phase to flow out of the reactor with the liquid phase. Experiments conducted by the inventors have shown that compared with the expansion-type reactor of the prior art (i.e., a design with a larger radial dimension of the reactor at the three-phase separator), the straight-cylinder reactor of the present invention has a better effect in preventing bubbles from rising. According to the fluid mechanics principle that bubbles tend to rise in a straight line, the "reverse order" of the material flow direction of the present invention and the "sequential order" in the prior art realize the interchange of the two deflection zones, which can effectively prevent bubbles from entering the liquid-solid separation space and interfering with the liquid-solid separation, thereby effectively maintaining the long-term stability of the separation efficiency of the three-phase separator.

[0031] 2) In order to solve the problem of uneven liquid outflow, the liquid-phase material after the third deflection is guided to the liquid outlet pipe through a diversion buffer unit. The liquid baffle of the diversion buffer unit extends downwardly and obliquely from the inner wall of the outer guide tube in a certain circumferential range directly above the liquid outlet pipe toward the direction away from the liquid outlet pipe, which can effectively alleviate the excessive suction of the liquid-phase material into the liquid outlet pipe after the third deflection; the diversion buffer baffle of the diversion buffer unit is arranged at the bottom of the third annular space between the central guide tube and the overflow guide tube, and is inclined downwardly from the far side away from the liquid outlet pipe toward the liquid outlet pipe to receive the liquid drainage from the liquid baffle and guide the liquid from the far side away from the liquid outlet pipe toward the liquid outlet pipe, and discharge it evenly from the liquid outlet pipe.

[0032] 3) The anti-deposition portion of the present invention is an annular air-filled space located at the bottom of the guide buffer baffle for generating bubbles. After the annular air-filled space is filled with gas, the gas can enter the liquid outflow area in a controlled manner, so that the bubbles generated at the holes form turbulence for the liquid phase material on the guide buffer baffle, thereby preventing solid residues from being deposited on the guide buffer baffle.

[0033] 4) The guide portion of the present invention can be configured as a baffle-type structure. The bump structure needs to withstand pressure under high-pressure conditions. Therefore, compared to the annular bump structure, the baffle-type structure does not need to consider the pressure-bearing problem and is the preferred structure. The annular baffle extends downwardly and radially inward from the inner wall of the reactor shell relative to the vertical center axis of the outer shell, so that bubbles accumulate in the space between the annular baffle and the side wall of the reactor shell and form a large bubble cavity, forming a state of contact between the air film and the liquid film, thereby reducing wear on the solid catalyst particles.

[0034] Further areas of applicability of the present disclosure will become apparent from the detailed description, claims and drawings.The detailed description and specific examples are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] The present disclosure will be more fully understood from the detailed description and accompanying drawings.

[0036] FIG1 is a schematic cross-sectional view of a straight sequential type built-in three-phase separator of a conventional ebullated bed reactor.

[0037] FIG2 is a schematic cross-sectional view of a straight-tube reverse-sequence built-in three-phase separator according to an example of the present invention.

[0038] FIG3 is a schematic diagram of the three-phase separator according to an example of the present invention.

[0039] FIG4 is a schematic diagram of the three-dimensional structure of a flow guide buffer baffle and an anti-deposition portion of a three-phase separator according to an example of the present invention.

[0040] FIG5 is a schematic cross-sectional view of an example of an ebullated bed reactor according to the present invention.

[0041] FIG6 is a schematic perspective view of an example of an ebullated bed reactor according to the present invention. DETAILED DESCRIPTION

[0042] The specific embodiments of the present invention are described in detail below with reference to the accompanying drawings. However, it should be understood that the protection scope of the present invention is not limited by the specific embodiments.

[0043] Unless expressly stated otherwise, throughout the specification and claims, the term “comprise” or variations such as “include” or “have”, etc., will be understood to include the stated elements or components but not to exclude other elements or components.

[0044] In this document, for ease of description, spatially relative terms such as "below", "beneath", "down", "above", "above", etc. may be used to describe the relationship of one element or feature to another element or feature in the accompanying drawings. It should be understood that the spatially relative terms are intended to encompass different orientations of the object in use or operation in addition to the orientation depicted in the drawings. For example, if the object in the drawings is turned over, the element described as being "below" or "below" other elements or features will be oriented "above" the element or feature. Therefore, the exemplary term "below" can include both the below and above directions. Objects may also have other orientations (rotated 90 degrees or other orientations) and the spatially relative terms used herein should be interpreted accordingly.

[0045] In this document, the terms "first", "second", etc. are used to distinguish two different elements or parts, and are not used to limit specific positions or relative relationships. In other words, in some embodiments, the terms "first", "second", etc. can also be interchangeable with each other.

[0046] Figure 1 shows a conventional ebullated bed reactor 100A for gas-liquid-solid three-phase reactions, comprising an inner cylinder 1A and an outer cylinder 2A. A gas-liquid mixture feeds from the bottom of the reactor and contacts solid catalyst particles disposed in the lower middle portion of the reactor, causing a catalytic reaction. The gas-liquid-solid mixture continues upward and enters a three-phase separator. The conventional three-phase separator is located in the upper middle portion of the reactor and is used for gas-liquid-solid separation. The material flow in this conventional three-phase separator is as follows: the gas-liquid-solid mixture flows upward within the annular inner cylinder 1A, completing gas-phase separation at the upper gas-liquid interface. Thereafter, the liquid-solid mixture flows radially outward into the area between the annular outer cylinder 2A and the inner cylinder 1A, and flows downward. In the area below the annular outer cylinder 2A, the solids separate from the liquid due to the density difference between the solids and the liquid, and flow out of the separator, returning to the main reaction zone. The remaining liquid, acting under the "U"-shaped tube principle, flows upward in the annular space between the annular outer cylinder 2A and the sidewall of the reactor shell and exits the reactor through outlet pipe 3A. That is to say, a gas phase outlet 4A is provided at the top of the reactor, and the liquid phase overflows out of the reactor through the outlet pipe 3A on the side, and the solid catalyst flows out of the separator under the action of the density difference, thereby realizing three-phase separation. This three-phase separator is called a straight-cylinder sequential type built-in three-phase separator. "Sequential type" means that the direction of the rising of the bubbles is the same as the direction of the liquid in the liquid outflow area. Referring to the direction of the arrows at the three-phase separator in Figure 1, the material moves upward along the inner cylinder 1A, and then enters the annular space between the inner cylinder 1A and the outer cylinder 2A and moves downward, and then after liquid-solid separation, the liquid phase moves upward along the annular space between the outer cylinder 2A and the side wall of the reactor shell, and overflows out of the reactor 100A when the liquid phase rises to the outlet pipe 3A.

[0047] The inventors have found through research that the sequential built-in three-phase separators of the prior art are usually difficult to achieve a satisfactory interception rate of solid phase particles (solid catalyst particles) and maintain a stable and efficient separation efficiency. The straight-cylinder three-phase separators of the prior art are difficult to avoid bubbles entering the three-phase separator from the gap between the inner cylinder 1A and the side wall of the reactor shell. The area where the bubbles enter is the liquid-solid separation area and the liquid outflow area. When the gas enters the liquid-solid separation area (i.e., the area between the lower end of the inner cylinder 1A and the side wall of the reactor shell in Figure 1), the rising of the bubbles will disrupt the normal separation and sedimentation process of the liquid-solid separation area. The rising direction of the bubbles is the same as the direction of the liquid outflowing from the reactor (i.e., moving upward in the annular space between the outer cylinder 2A and the side wall of the reactor shell in Figure 1), which can easily cause the solid phase to flow out of the reactor with the liquid phase, and the separation effect is deteriorated. Compared with the straight-cylinder three-phase separator, the expansion-type three-phase separator can reduce the intrusion of bubbles to a certain extent, but it is more difficult to apply in engineering, the design is complex, the cost is high, and it is also difficult to avoid the intrusion of bubbles.

[0048] In order to solve the above-mentioned problems in the prior art, as shown in Figures 2 and 3, the present invention provides a three-phase separator, which adopts a "reverse-type" flow path structural design, is arranged at the upper part of the fluidized bed reactor and is used for gas-liquid-solid three-phase separation. The three-phase separator includes: an outer shell 101, a central draft tube 11, an outer draft tube 2 and an overflow draft tube 3. The central draft tube 11 is arranged in the outer shell 101 and is configured to receive gas, liquid and solid materials. The outer draft tube 2 is arranged radially outside the central draft tube 11, thereby forming a first annular space between the outer draft tube 2 and the outer shell 101. The upper sealing baffle 4 extends radially between the central draft tube 11 and the outer draft tube 2 and is sealedly connected to the top of the central draft tube 11 and the top of the outer draft tube 2. The overflow guide tube 3 is disposed between the central guide tube 11 and the outer guide tube 2, thereby forming a second annular space between the outer guide tube 2 and the overflow guide tube 3, and a third annular space between the overflow guide tube 3 and the central guide tube 11. A gap is defined between the top of the overflow guide tube 3 and the upper sealing baffle 4. A lower sealing baffle 63 extends radially between the outer guide tube 2 and the overflow guide tube 3 and is sealingly connected to the bottom end of the outer guide tube 2 and the bottom of the overflow guide tube 3. As shown in FIG2 , the lower sealing baffle 63 is connected to the lower sealing baffle 63 at a distance above the bottom end of the overflow guide tube 3, so that the bottom end of the overflow guide tube 3 protrudes downward from the lower sealing baffle 63 by a certain distance. This further prevents air bubbles from entering and facilitates liquid-solid separation. However, it should be understood that the lower sealing baffle 63 may also be connected to the lower sealing baffle 63 at the bottom end of the overflow guide tube 3 without departing from the scope of the present invention. The liquid outlet pipe 7 extends radially outward from the bottom of the outer guide tube 2 above the lower sealing baffle 63 to the outside of the outer shell, and is configured to discharge the separated liquid.

[0049] The central draft tube 11 receives gaseous and liquid materials, along with the solid catalyst particles, traveling upward from the bottom of the reactor 100. The gas phase separates at the reactor liquid level B, and the liquid and solid materials undergo a first deflection at the top of the central draft tube 11. The outer draft tube 2 is disposed radially outward of the central draft tube 11. After the first deflection, the liquid and solid materials travel downward in the first annular space between the outer draft tube 2 and the sidewall of the reactor shell. The overflow guide tube 3 is disposed between the central guide tube 11 and the outer guide tube 2. Liquid-solid material separation and a second deflection of the liquid phase material occur below the lower sealing baffle 63. After the second deflection, the liquid phase material moves upward in the second annular space between the outer guide tube 2 and the overflow guide tube 3 (according to the U-tube principle). The liquid phase material undergoes a third deflection at the upper end of the overflow guide tube 3. The liquid phase material, after the third deflection, moves downward in the third annular space between the overflow guide tube 3 and the central guide tube 11 and is discharged from the liquid outlet pipe 7 located at the lower wall of the outer guide tube 2. Compared to the prior art, the present invention adopts a "three-tube socket" structure and changes the material flow direction (see FIG. 2 ). This material flow direction is similar to a "paper clip" and is significantly different from the "sequential" material flow direction of the prior art. The material flow direction of the present invention adopts a "reverse type" material flow direction based on the "three-tube sleeve" structure, that is, the rising direction of the bubbles is opposite to the downward direction of the liquid in the liquid outflow area.

[0050] As further shown in Figures 2 and 3, the top end of the central draft tube 11 is connected to the top end of the outer draft tube 2 via an upper sealing baffle 4. According to an example of the present invention, the upper sealing baffle 4 can be configured to be tilted downward in a radially outward direction relative to the vertical central axis 110 of the outer shell 101. The use of the downwardly tilted upper sealing baffle 4 can better guide the material from the central draft tube 11 directly into the first annular space between the outer draft tube 2 and the side wall of the outer shell 101 / reactor shell. According to an example of the present invention, the upper sealing baffle 4 is tilted at an angle of between 5° and 45° relative to a horizontal plane perpendicular to the vertical central axis 110 of the outer shell 101, preferably, at an angle of between 10° and 30°. It should be understood that the upper sealing baffle 4 can be tilted at any suitable angle relative to the horizontal plane perpendicular to the vertical central axis 110 of the outer shell 101 without departing from the scope of the present invention.

[0051] As further shown in Figures 2 and 3, the three-phase separator may also include an annular bubble baffle 12 extending downward and obliquely in a radially outward direction from the bottom end of the central guide tube 11 relative to the vertical central axis 110 of the outer shell 101. According to an example of the present invention, the annular bubble baffle 12 may extend to a radial position between the outer guide tube 2 and the outer shell 101. Therefore, even if some of the upward bubbles reach the liquid-solid separation area, it is difficult for the bubbles to continue to move upward and affect the liquid-solid separation because the straight-line upward path of the bubbles is interrupted. The central guide tube 11 and the annular bubble baffle 12 can be in an integrated form. However, it should be understood that the central guide tube 11 and the annular bubble baffle 12 can also be formed separately and fixed together by, for example, welding, without departing from the scope of the present invention.

[0052] According to an example of the present invention, the three-phase separator may further include an exhaust pipe 8 extending upward from the upper sealing baffle 4 near the central guide tube 11 to above the liquid level B of the three-phase separator. The exhaust pipe 8 may be multiple and arranged in the form of an annular array around the vertical center axis 110 of the outer shell 101. However, it should be understood that the exhaust pipe 8 may also take other forms without departing from the scope of the present invention. It should be understood that a single exhaust pipe 8 may also be used without departing from the scope of the present invention. The outlet of the exhaust pipe 8 is located above the liquid level of the three-phase separator (refer to Figure 5). The arrangement of the exhaust pipe 8 array can prevent the gas from mixing into the overflow zone through the catalyst discharge port (i.e., the gap between the annular bubble baffle 12 and the outer shell 101) to cause a cavity.

[0053] The inventors further discovered through research that the size of the liquid outlet of the "sequential type" three-phase separator in the prior art (see Figure 1) does not match the volume of the annular gap / space formed between the outer cylinder and the side wall of the reactor shell. The area directly below the liquid outlet is the main outflow area, the fluid in the area farther from the outlet is almost motionless, and the outflow from the annular space is uneven.

[0054] To address the uneven outflow from the annular space, the present invention proposes that the liquid-phase material, after the third deflection, be discharged to the liquid outlet pipe 7 through a diversion buffer unit, which includes a liquid baffle 5 and a diversion buffer baffle 6. Specifically, referring to Figures 2 to 4, the three-phase separator may further include a liquid baffle 5, which extends downwardly and obliquely from the inner wall of the outer guide tube 2 in a direction away from the liquid outlet pipe 7 within a certain circumferential range directly above the liquid outlet pipe 7. According to an example of the present invention, the liquid baffle 5 may extend circumferentially by 30%-60%, preferably 40%-50%, of the circumference of the inner wall of the outer guide tube 2. It should be understood that the liquid baffle 5 may extend circumferentially by any suitable proportion of the circumference of the inner wall of the outer guide tube 2 without departing from the scope of the present invention. The three-phase separator may further include a guide buffer baffle 6, which is arranged at the bottom of the third annular space, immediately below the liquid outlet pipe 7, and is arranged to be inclined downward from the far side away from the liquid outlet pipe 7 toward the liquid outlet pipe 7.

[0055] The liquid entering the third annular space is blocked by the liquid baffle 5 to avoid being discharged directly from the liquid outlet pipe 7. Instead, it is guided by the liquid baffle 5 to the far side of the guide buffer baffle 6 away from the liquid outlet pipe 7. The liquid flows downward from the far side away from the liquid outlet pipe 7 toward the liquid outlet pipe 7 and is discharged evenly from the liquid outlet pipe 7. Preferably, but not restrictively, as shown in Figure 2, the liquid baffle 5 is inclined at an angle between 40° and 80° relative to the horizontal plane perpendicular to the vertical center axis 110 of the outer shell 101, preferably at an angle between 60° and 70°; the guide buffer baffle 6 is inclined at an angle between 5° and 20° relative to the horizontal plane perpendicular to the vertical center axis 110 of the outer shell 101. However, it should be understood that those skilled in the art can adopt any other suitable inclination angles for the liquid baffle 5 and the guide buffer baffle 6 without departing from the scope of the present invention. The uniformity of the outflow from the third annular space is also a key factor in the stable and long-lasting performance of the three-phase separator. The liquid baffle 5 arranged in the third annular space between the central guide tube 11 and the overflow guide tube 3 and the guide buffer baffle 6 arranged at the bottom can prevent the local flow field speed in the third annular space from being too fast, effectively solve the outflow uniformity problem of the third annular space, and help maintain the stability of the separation efficiency of the solid-liquid separation zone.

[0056] As further shown in Figures 2 to 4, an anti-deposition portion may be provided at the bottom of the flow-guiding buffer baffle 6. The anti-deposition portion is integrally formed with the flow-guiding buffer baffle 6 and the lower sealing baffle 63 and is an annular gas-filled space 61 with a closed bottom (see Figure 4). The flow-guiding buffer baffle 6 is provided with a plurality of holes 60, which are in fluid communication with the annular gas-filled space 61 defined between the flow-guiding buffer baffle 6 and the lower sealing baffle 63. The anti-deposition portion of the three-phase separator further includes a gas filling pipe 62, which extends radially outward from the outer guide tube 2 to the outside of the outer shell and is in fluid communication with the annular gas-filled space 61. The gas filling pipe 62 is configured to guide gas into the annular gas-filled space 61 so that bubbles generated at the holes 60 form turbulence for the liquid-phase material on the flow-guiding buffer baffle 6.

[0057] Since the guide buffer baffle 6 used in the present invention is an inclined annular plate, the liquid located at the far side away from the liquid outlet pipe 7 has the potential energy to flow toward the liquid outlet pipe 7, which plays a role in uniformizing the liquid flow rate in the third annular space at the liquid outlet pipe 7. The anti-deposition portion is an annular air-filled space located at the lower part of the guide buffer baffle 6 for generating bubbles. The gas enters the annular air-filled space 61 through the air filling port 62. After the annular air-filled space 61 is filled with gas, the gas can enter the liquid outflow area (i.e., above the inclined surface of the guide buffer baffle 6) through an optional one-way gas control valve (not shown in the figure). The bubbles generated increase the turbulence of the liquid at the guide buffer baffle 6 to prevent solid residues from being deposited on the guide buffer baffle 6, thereby playing a role in preventing coking.

[0058] As shown in Figures 5 and 6, an ebullated bed reactor 100 is provided, in which a three-phase separator according to the present invention is disposed. Specifically, the reactor shell is a straight cylindrical structure, including a straight cylindrical portion, an upper head, and a lower head. The outer shell 101 of the three-phase separator is part of the straight cylindrical portion of the reactor shell. The upper head is provided with a gas outlet 103 (preferably at its center), and the center of the lower head is provided with a feed inlet 104.

[0059] The ebullated bed reactor 100 may further include a gas-liquid distributor 105 disposed in the lower space of the reactor shell. The upper end cap is provided with a solid catalyst particle filling port 106, and the lower end cap is provided with a solid catalyst particle discharge port 107.

[0060] As further shown in Figures 5 and 6, a guide portion may be provided at a corresponding position on the lower end of the annular bubble baffle 12 of the three-phase separator. The guide portion cooperates with the annular bubble baffle 12 to prevent bubbles in the gas-liquid-solid material from entering the first annular space between the outer draft tube 2 and the reactor shell. The guide portion is an annular projection structure or a baffle-like structure circumferentially disposed around the inner wall of the reactor shell. The annular projection structure may, for example, be a trapezoidal or arcuate structure, considering that the annular projection structure needs to withstand pressure under high-pressure conditions. Compared to the annular projection structure, as shown in Figures 5 and 6, according to an example of the present invention, the guide portion may include an annular baffle 102, which may extend downwardly and radially inwardly from the inner wall of the reactor shell relative to the vertical central axis 110 of the outer shell 101. According to an example of the present invention, the annular baffle 102 may be inclined at an angle between 40° and 80°, preferably between 60° and 70°, relative to a horizontal plane perpendicular to the vertical central axis 110 of the outer shell 101. However, it should be understood that the annular baffle 102 may be inclined at any other suitable angle relative to a horizontal plane perpendicular to the vertical central axis 110 of the outer housing 101 without departing from the scope of the present invention.

[0061] The operation of the ebullated bed reactor is described in detail below by combining the material flow direction in the ebullated bed reactor of the present invention:

[0062] First, the various regions of the three-phase separator installed within the fluidized bed reactor 100 are described: the central draft tube 11 constitutes the central flow-guiding area of ​​the three-phase separator. The first annular space between the outer draft tube 2 and the sidewall of the reactor shell constitutes the liquid-solid descending zone. The second annular space between the overflow draft tube 3 and the outer draft tube 2 constitutes the overflow zone. The third annular space between the overflow draft tube 3 and the central draft tube 11 constitutes the liquid outflow zone, which serves as the collection area for the clean liquid product. The area above the upper sealing baffle 4 is the first deflection zone, the area below the lower sealing baffle 63 is the second deflection zone, and the area at the top end of the overflow draft tube 3 is the third deflection zone.

[0063] The gas-liquid mixture enters the gas-liquid distributor 105 through the feed port 104 at the bottom of the reactor, and then enters the catalyst bed A (the catalyst is solid catalyst particles), where a gas-liquid-solid three-phase reaction occurs in the lower part of the reactor. After the reaction, the gas-liquid-solid three-phase mixture flows upward and enters the three-phase separator. The three-phase separator is sequentially divided into a central flow zone, a first deflection zone, a liquid-solid descending zone, a second deflection zone, an overflow zone, a third deflection zone, and a liquid outflow zone. According to the present invention, the gas, liquid, and solid materials move upward along the central flow zone defined by the central guide tube 11, and gas phase separation occurs at the liquid surface above the central guide tube 11. The separated gas is discharged through the gas outlet 103. The liquid-solid mixture undergoes a first deflection in the first deflection zone above the upper sealing baffle 4, enters the first annular space (also called the liquid-solid descending zone) between the outer guide tube 2 and the outer shell 101 along the upper surface of the upper sealing baffle 4, and moves downward along the first annular space. The liquid-solid mixture undergoes a second deflection in the second deflection zone below the lower sealing baffle 63. Due to the density difference between the liquid and the solid, the liquid-solid mixture undergoes liquid-solid separation below the outer guide tube 2. The separated solid catalyst particles leave the three-phase separator and return to the solid catalyst particle bed A. The liquid and a small amount of entrained solid catalyst particles enter the second annular space (also called the overflow zone) between the outer guide tube 2 and the overflow guide tube 3 along the lower surface of the lower sealing baffle 63, and move upward along the second annular space. The liquid undergoes a third deflection in the third deflection zone above the top of the overflow guide tube 3, passes through the gap between the top of the overflow guide tube 3 and the upper sealing baffle 4, and enters the third annular space (also called the liquid outflow zone) between the central guide tube 11 and the overflow guide tube 3 along the lower surface of the upper sealing baffle 4, and moves downward along the third annular space. Due to the collision of the liquid with the lower surface of the upper sealing baffle 4, the unseparated solids are further separated.

[0064] The liquid-solid two-phase mainly completes liquid-solid separation in the second baffle area. The liquid flows into the third baffle area under the action of the "U"-shaped tube principle. After further separation in the third baffle area, it enters the liquid outflow area and flows out of the reactor through the liquid outlet pipe 7. Specifically, the gas-liquid-solid three-phase mixture first flows upward through the central guide area through the annular bubble baffle 12 of the central guide tube 11. The flow area gradually decreases, the mixture flow rate increases, and a jet is formed at the liquid level interface of the three-phase separator (i.e., the reactor liquid level B). The gas is separated here and discharged from the gas outlet 103. After the liquid-solid flow overflows the central guide tube 11 and enters the first baffle area, it flows into the liquid-solid descending area, and liquid-solid separation is carried out in the second baffle area. The separated catalyst returns to the reaction zone (solid catalyst particle bed) through the discharge port. After separation, the clean liquid is obtained and enters the clean liquid collection area through the second baffle area. An exhaust pipe 8 is provided at the top of the overflow area to prevent the gas from mixing into the overflow area through the catalyst discharge port to cause a cavity. The liquid passes through the liquid baffle 5 and the lower guide buffer baffle 6 to adjust the flow field, and then flows out of the reactor through the liquid outlet pipe 7.

[0065] The present invention realizes the "reverse" (paper clip flow direction) of the material flow direction through the structural design of "three-tube socket", increases the radial stroke of the first deflection and the second deflection, so that the material of the central guide tube 11 is directly deflected to the first annular space between the outer guide tube 2 and the side wall of the reactor shell, and thus the radial stroke of the second deflection is also effectively increased relative to the prior art, and the gas is not easy to rise in the liquid-solid separation area. In addition, since the present invention adopts the "reverse" material flow direction, even if some bubbles rise, since their rising direction is opposite to the direction of the liquid flowing out of the three-phase separator / reactor, it is not easy to cause the solid phase to flow out of the three-phase separator / reactor with the liquid phase. In addition, the present invention uses a straight-cylinder reactor, which is better than the expansion-type reactor of the prior art in preventing bubbles from rising. In addition, although the present invention uses a straight-cylinder reactor, the present invention can also be applied to an expansion-type reactor without departing from the scope of the present invention.

[0066] In order to solve the problem of uneven liquid outflow, the liquid-phase material after the third deflection is guided to the liquid outlet pipe 7 through the diversion buffer unit. The liquid baffle 5 of the diversion buffer unit extends downwardly and obliquely from the inner wall of the outer guide tube 2 toward the direction away from the liquid outlet pipe 7 within a certain circumferential range just above the liquid outlet pipe 7, which can effectively alleviate the excessive suction of the liquid-phase material into the liquid outlet pipe 7 after the third deflection; the diversion buffer baffle 6 of the diversion buffer unit is arranged at the bottom of the third annular space between the central guide tube 11 and the overflow guide tube 3, and is inclined downward from the far side away from the liquid outlet pipe 7 toward the liquid outlet pipe 7 to receive the liquid drainage from the liquid baffle 5 and guide the liquid from the far side away from the liquid outlet pipe 7 toward the liquid outlet pipe 7, and discharge it evenly from the liquid outlet pipe 7.

[0067] After the annular inflation space 61 is filled with gas, the gas can enter the liquid outflow area in a controlled manner, so that the bubbles generated at the hole 60 form turbulence for the liquid phase material on the guide buffer baffle 6, thereby preventing solid residues from being deposited on the guide buffer baffle 6.

[0068] Compared with the annular protrusion structure, the annular baffle 102 extends downwardly and obliquely from the inner wall of the reactor shell relative to the vertical center axis 110 of the outer shell 101 in a radially inward direction, so that bubbles accumulate and form large bubble cavities in the space between the annular baffle 102 and the side wall of the reactor shell, forming a contact state between the gas film and the liquid film, thereby reducing the wear on the solid catalyst particles.

[0069] The preferred embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited thereto. Within the scope of the technical concept of the present invention, the technical solution of the present invention may be subjected to a variety of simple modifications, including combining the various specific technical features in any suitable manner. To avoid unnecessary repetition, the present invention will not further describe various possible combinations. However, these simple modifications and combinations should also be regarded as disclosed in the present invention and fall within the scope of protection of the present invention.

[0070] Reference Signs List

[0071] 1A: inner cylinder;

[0072] 2A: outer tube;

[0073] 3A: liquid outlet pipe;

[0074] 4A: gas outlet;

[0075] 100A: prior art ebullated bed reactor;

[0076] 2: External guide tube;

[0077] 3: Overflow guide tube;

[0078] 4: Upper sealing baffle;

[0079] 5: Liquid baffle;

[0080] 6: diversion buffer baffle;

[0081] 7: Liquid outlet pipe;

[0082] 8: Exhaust pipe;

[0083] 11: Center guide tube;

[0084] 12: Annular bubble baffle;

[0085] 60: hole;

[0086] 61: annular inflatable space;

[0087] 62: Inflatable tube;

[0088] 63: lower sealing baffle;

[0089] 100: fluidized bed reactor;

[0090] 101: external shell;

[0091] 102: annular baffle;

[0092] 103: gas outlet;

[0093] 104: feed port;

[0094] 105: gas-liquid distributor;

[0095] 106: solid catalyst particle filling port;

[0096] 107: solid catalyst particle discharge port;

[0097] 110: vertical center axis;

[0098] A: bed of solid catalyst particles;

[0099] B: Liquid level in the three-phase separator.

Claims

1. A three-phase separator, comprising: An outer shell (101); A central flow guide cylinder (11), the central flow guide cylinder (11) is disposed in the outer shell (101) and is configured to receive gas, liquid, and solid materials; An external flow guide cylinder (2), wherein the external flow guide cylinder (2) is arranged radially outside the central flow guide cylinder (11); an upper sealing baffle (4), the upper sealing baffle (4) extending radially between the central flow guide tube (11) and the outer flow guide tube (2) and being sealingly connected to the top end of the central flow guide tube (11) and the top end of the outer flow guide tube (2); An overflow guide tube (3), wherein the overflow guide tube (3) is arranged between the central guide tube (11) and the outer guide tube (2), and a gap is provided between the top end of the overflow guide tube (3) and the upper sealing baffle (4); a lower sealing baffle (63), the lower sealing baffle (63) extending radially between the external guide tube (2) and the overflow guide tube (3) and being sealingly connected to the bottom end of the external guide tube (2) and the bottom of the overflow guide tube (3); as well as A liquid outlet pipe (7) extends radially outward from the bottom of the outer guide tube (2) above the lower sealing baffle (63) to the outside of the outer shell and is configured to discharge the separated liquid.

2. The three-phase separator according to claim 1, characterized in that: The upper sealing baffle (4) is arranged to be inclined downward in a radially outward direction relative to a vertical central axis (110) of the outer shell (101).

3. The three-phase separator according to claim 1, characterized in that: The three-phase separator further comprises an annular bubble baffle (12) extending obliquely downward from the bottom end of the central draft tube (11) in a radially outward direction relative to the vertical central axis (110) of the outer shell (101).

4. The three-phase separator according to claim 1, characterized in that: The three-phase separator further comprises a liquid baffle (5), wherein the liquid baffle (5) extends obliquely downward from the inner wall of the outer guide tube (2) in a certain circumferential range directly above the liquid outlet pipe (7) in a direction away from the liquid outlet pipe (7).

5. The three-phase separator according to claim 4, characterized in that: The three-phase separator further comprises a flow guide buffer baffle (6), which is arranged at the bottom of a third annular space between the overflow guide tube (3) and the central guide tube (11), immediately below the liquid outlet pipe (7), and arranged to be inclined downward from the far side away from the liquid outlet pipe (7) toward the liquid outlet pipe (7).

6. The three-phase separator according to claim 5, characterized in that: The guide buffer baffle (6) is provided with a plurality of holes (60), and the plurality of holes (60) are in fluid communication with an annular gas-filled space (61) defined between the guide buffer baffle (6) and a lower sealing baffle (63). The three-phase separator also includes an air filling pipe (62), which extends radially outward from the outer guide cylinder (2) to the outside of the outer shell and is in fluid communication with the annular gas-filled space (61), and is configured to guide gas into the annular gas-filled space (61), so that bubbles generated at the holes (60) form turbulence on the liquid phase material on the guide buffer baffle (6).

7. The three-phase separator according to claim 5, characterized in that: The flow guide buffer baffle (6) is inclined at an angle between 5° and 20° relative to a horizontal plane perpendicular to the vertical center axis (110) of the outer shell (101).

8. The three-phase separator according to claim 2, characterized in that: The three-phase separator further comprises an exhaust pipe (8) extending upward from the upper sealing baffle (4) near the central guide tube (11) to above the liquid level (B) of the three-phase separator.

9. The three-phase separator according to claim 8, characterized in that: A plurality of exhaust pipes (8) are arranged in a circular array around a vertical central axis (110) of the outer shell (101).

10. An ebullating bed reactor (100), comprising: Reactor shell; and According to the three-phase separator according to any one of claims 1 to 9, the three-phase separator is arranged at the upper part of the ebullating bed reactor (100), and the outer shell of the three-phase separator is a part of the reactor shell.

11. The ebullated bed reactor according to claim 10, characterized in that: The reactor shell comprises: a straight cylinder part, an upper end cap and a lower end cap, the upper end cap is provided with a gas outlet (103), and a feed inlet (104) is provided at the center of the lower end cap.

12. The ebullated bed reactor according to claim 10, characterized in that: The fluidized bed reactor further comprises a gas-liquid distributor (105), and the gas-liquid distributor (105) is arranged in the lower space of the reactor shell.

13. The ebullated bed reactor according to claim 11, characterized in that: The upper end cap is provided with a solid catalyst particle filling port (106); the lower end cap is provided with a solid catalyst particle discharge port (107).

14. The ebullated bed reactor according to claim 10, characterized in that: It also includes a guide portion arranged below the annular bubble baffle (12) of the three-phase separator and circumferentially arranged around the inner wall of the reactor shell, and the guide portion cooperates with the annular bubble baffle (12) to prevent bubbles in the gas, liquid and solid materials from entering the first annular space between the external guide tube (2) and the reactor shell.

15. The ebullated bed reactor according to claim 14, characterized in that: The guide portion includes an annular baffle (102) extending obliquely downward from an inner wall of the reactor shell in a radially inward direction relative to a vertical center axis (110) of the outer shell (101).

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