Charging system and charging method for solid catalyst

Abstract

The invention discloses an intermittent charging system of a solid catalyst and a charging method of the solid catalyst in a propylene dimerization process. The intermittent feeding system comprises a feeding barrel section, the feeding barrel section comprises an upper barrel section and a lower barrel section, a feeding device is arranged between the upper barrel section and the lower barrel section, the top of the upper barrel section and the bottom of the lower barrel section are provided with a first discharging valve and a second discharging valve respectively, and the side wall of the upper barrel section is provided with a purging gas inlet and an exhaust port; and the charging barrel section is communicated with a charging hole of the reaction kettle. The system and the method provided by the invention not only can meet strict requirements of the process on anhydrous and anaerobic conditions of the catalyst, but also can realize intermittent addition of the catalyst without influencing normal operation of the device, and are convenient to replace.

Description

Technical Field

[0001] The invention relates to the technical field of propylene dimerization, in particular to an intermittent feeding system of a solid catalyst and a feeding method of the solid catalyst in a propylene dimerization process. Background Art

[0003] The present invention aims to utilize China's abundant olefin resources to synthesize branched α-olefins through propylene dimerization technology, which can not only be used as comonomers of linear low-density polyethylene, but also can be self-polymerized to prepare a new type of thermoplastic resin PMP.

[0004] The defects existing in the prior art include: the existing propylene dimerization catalyst feeding technology adopts in-situ configuration, and directly pours into the reactor at the reserved opening on the top of the reactor; first, it inevitably causes catalyst contamination and is very dangerous; second, the reserved opening is small, which easily causes poor catalyst feeding.

[0005] The present invention is conducive to increasing the technical accumulation of olefin oligomerization and achieving a breakthrough in functional monomer technology. At the same time, the present invention realizes the continuous propylene dimerization reaction, which is expected to fill the gap in the production technology of propylene dimerization to 4-methyl-1-pentene in my country and provide sufficient raw materials for the production of PMP, which is of great significance. Summary of the invention

[0007] In order to solve the problems existing in the above-mentioned prior art, the present invention provides an intermittent feeding system of a solid catalyst and a feeding method of a solid catalyst in a propylene dimerization process, which can not only meet the stringent requirements of the process on catalyst conditions, but also realize intermittent addition of the catalyst without affecting the normal operation of the device.

[0008] One of the purposes of the present invention is to provide an intermittent feeding system for solid catalysts, comprising a feeding barrel section, the feeding barrel section comprising an upper barrel section and a lower barrel section, a feeding device is arranged between the upper barrel section and the lower barrel section, a first unloading valve and a second unloading valve are arranged at the top of the upper barrel section and the bottom of the lower barrel section respectively, and a purge gas inlet and an exhaust port are arranged on the side wall of the upper barrel section; the feeding barrel section is connected to the feeding port of the reactor.

[0009] According to a preferred embodiment of the present invention, the feeding cylinder section is vertically arranged on the top of the reactor, and the bottom of the lower cylinder section is connected to the feeding port on the top of the reactor through a flange.

[0010] According to a preferred embodiment of the present invention, the upper barrel section and the lower barrel section are cylindrical structures, and the inner and outer diameters of the upper barrel section and the lower barrel section are the same.

[0011] According to one embodiment of the present invention, the feeding device includes a shell, a rotating shaft, blades, a sealing plate and a flange cover, wherein the shell has a four-way tubular structure, the inner diameters of the upper and lower ports of the tube body in the vertical axis direction of the shell are the same as the inner diameter of the feeding barrel section, and the upper and lower ports are respectively connected to the upper barrel section and the lower barrel section, the inner diameter of the tube body in the vertical axis direction of the shell is less than or equal to the inner diameter of the tube body in the horizontal axis direction of the shell, the rotating shaft is arranged at a coaxial position of the horizontal axis of the shell, the blades are arranged on the rotating shaft, the length direction of the blades is consistent with the axial direction of the rotating shaft, the sealing plates are vertically arranged at positions on both sides of the rotating shaft and the blades, the structure surrounded by two sealing plates or the structure surrounded by two sealing plates and the inner wall of the tube body in the horizontal direction of the shell, the inner side of the central horizontal cross-section is matched with the outer edge of the blade, the left and right ports in the horizontal axis direction of the shell are sealed with flange covers, and the rotating shaft passes through the sealing plates and the flange covers.

[0012] According to one embodiment of the present invention, the upper and lower ports in the vertical axis direction of the shell can be welded to the charging barrel section, or connected through flanges.

[0013] According to one embodiment of the present invention, the tube body in the horizontal axis direction of the shell is a cylindrical structure, and the tube body in the vertical axis direction of the shell is a cylindrical structure, and the two are interconnected.

[0014] According to one embodiment of the present invention, the tube body in the horizontal axis direction of the shell is a cylindrical structure, the inner diameter of the tube body in the vertical axis direction of the shell remains unchanged, and the outside has a structure that gradually increases from the upper and lower diameter ends, and the upper and lower small-diameter ends are respectively connected to the upper and lower cylinder sections through flanges, and the tube body in the horizontal axis direction of the shell and the tube body in the vertical axis direction of the shell are interconnected.

[0015] According to an embodiment of the present invention, the blades are configured to be semicircular, circular or rectangular in shape to match the vertical cross-sectional dimensions of the tube in the horizontal direction of the shell; and the number of the blades is 1 to 4.

[0016] According to one embodiment of the present invention, when the number of blades is 1, the blade and the rotating shaft are an integrated structure, and the center line of the blade is the rotating shaft; the blade is circular or rectangular, and when it is circular, its diameter matches the inner diameter of the horizontal tube body of the shell; when it is rectangular, its vertical length matches the inner diameter of the horizontal tube body of the shell, and its horizontal length matches the inner diameter of the vertical tube body of the shell.

[0017] According to one embodiment of the present invention, when the number of blades is 2, two rotating shafts are arranged side by side and closely attached, and each rotating shaft is fixedly connected to a blade; the blade is semicircular or rectangular. When it is semicircular, its radius matches 1 / 2 of the inner diameter of the horizontal tube body of the shell; when it is rectangular, its vertical length matches 1 / 2 of the inner diameter of the horizontal tube body of the shell, and its horizontal length matches the inner diameter of the vertical tube body of the shell.

[0018] According to an embodiment of the present invention, when the number of blades is 3 or 4, the blades are fixedly connected to the rotating shaft, and the angles between the blades are preferably the same; the blades are semi-circular or rectangular. When the blade is semi-circular, its radius matches 1 / 2 of the inner diameter of the horizontal tube of the housing; when the blade is rectangular, its vertical length matches 1 / 2 of the inner diameter of the horizontal tube of the housing, and its horizontal length matches the inner diameter of the vertical tube of the housing.

[0019] According to a preferred embodiment of the present invention, when the number of blades is 3 or 4, the angles between the blades are the same.

[0020] According to an embodiment of the present invention, when the blade is semi-circular or circular, the sealing plate is a curved surface that matches the shape of the blade. The vertical center line on the sealing plate is a vertical straight line, and the horizontal center line on the sealing plate is an arc, preferably an arc of a semi-circle. The radius of the semi-circle matches the radius of the blade, and its projection in the vertical direction coincides with the vertical cross-sectional shape of the horizontal tube of the housing; the outer edge of the sealing plate is in clearance fit with the inner wall of the horizontal tube of the housing.

[0021] According to an embodiment of the present invention, when the blade is rectangular, the sealing plate is a circular flat plate, and its diameter is equal to the inner diameter of the horizontal tube of the housing. The outer edge of the sealing plate is in clearance fit with the inner wall of the horizontal tube of the housing.

[0022] According to a preferred embodiment of the present invention, when the number of blades is 1, 1 retaining post is provided on the inner wall of one side of the sealing plate. The angle between the line connecting the center point of the bottom surface of the retaining post and the center point of the sealing plate and the vertical center line on the sealing plate is 25° to 45°. The retaining post is preferably a cylindrical retaining post.

[0023] According to a preferred embodiment of the present invention, when the number of blades is 2, 2 retaining posts are provided on the inner wall of one side of the sealing plate. The angle between the line connecting the center point of the bottom surface of each retaining post and the center point of the sealing plate and the vertical center line on the sealing plate is 25° to 45°, and the 2 retaining posts are located on both sides of the vertical line passing through the center point of the sealing plate. The retaining posts are preferably cylindrical retaining posts.

[0024] According to a preferred embodiment of the present invention, when the number of blades is greater than 1, the root part where the blade is connected to the rotating shaft has an arc transition surface.

[0025] According to a preferred embodiment of the present invention, a nitrogen purge port is provided on the sealing plate on one side of the feeding device. The nitrogen purge port is connected to a nitrogen source through a pipeline passing through the flange cover on one side, where

[0026] When the number of blades is 1 or 2, one nitrogen purge port is provided, and the radial distance between the nitrogen purge port and the center point of the sealing plate is 1 / 20 to 1 / 8 of the inner diameter of the tube in the horizontal direction of the shell. When installing the sealing plate, it is preferred to align the nitrogen purge port with the vertical center line above the center point of the sealing plate.

[0027] When the number of blades is 3, three nitrogen purge ports are provided. The radial distance between each nitrogen purge port and the center point of the sealing plate is 1 / 20 to 1 / 8 of the inner diameter of the shell in the horizontal direction of the tube body, and preferably, the radial distance between each nitrogen purge port and the center point of the sealing plate is the same. Preferably, the three nitrogen purge ports are evenly distributed on the circumference with the center point of the sealing plate as the center point. When installing the sealing plate, it is preferred to place one nitrogen purge port on the vertical center line above the center point of the sealing plate.

[0028] When the number of blades is 4, 4 nitrogen purge ports are provided. The radial distance between each nitrogen purge port and the center point of the sealing plate is 1 / 20 to 1 / 8 of the inner diameter of the shell in the horizontal direction of the tube body, and preferably, the radial distance between each nitrogen purge port and the center point of the sealing plate is the same. Preferably, the 4 nitrogen purge ports are evenly distributed on the circumference with the center point of the sealing plate as the center point. When installing the sealing plate, it is preferred to align the two opposite nitrogen purge ports on the vertical center line above the center point of the sealing plate.

[0029] According to one embodiment of the present invention, a hose is connected to the nitrogen purge port pipeline.

[0030] According to one embodiment of the present invention, a PTFE (polytetrafluoroethylene) protective edge is provided on the edge of the blade, and preferably, the width of the protective edge is 5 to 10 mm.

[0031] According to one embodiment of the present invention, a Johnson net is provided at the exhaust port, and the filtering accuracy of the Johnson net can be determined according to the particle size range of the solid catalyst.

[0032] According to a preferred embodiment of the present invention, the filtering accuracy of the Johnson net is 5 to 50 μm.

[0033] The second object of the present invention is to provide a method for adding a solid catalyst in a propylene dimerization process, using the above-mentioned feeding system, comprising the following steps:

[0034] (1) Open the first feed valve at the top of the upper cylinder section and add solid catalyst through the feed hopper;

[0035] (2) After the solid catalyst falls into the feeding device, close the first feeding valve;

[0036] (3) introducing nitrogen gas into the purge gas inlet for purge;

[0037] (4) After the purging is completed, the second discharge valve at the bottom of the lower cylinder section is opened, and the rotating shaft rotates to allow the solid catalyst to enter the reactor.

[0038] According to one embodiment of the present invention, in step (3), nitrogen is introduced through the nitrogen purge port of the feeding device for purging, which can ensure that the catalyst is in a water-free and oxygen-free environment before entering the reactor.

[0039] According to one embodiment of the present invention, in step (4), when the rotating shaft drives the blade to rotate, if the blade hits the blocking column, the blocking column vibrates relative to the rotation of the blade, thereby allowing the material to be discharged more fully.

[0040] According to one embodiment of the present invention, when the number of blades is 1, the blades are initially in a horizontal state. After a certain amount of solid catalyst is added, the rotating shaft is controlled to drive the blades to rotate. When the blades hit the blocking column, they stop. After all the solid catalyst falls into the reactor, the rotating shaft is controlled to drive the blades to rotate so that the blades return to the initial state.

[0041] According to one embodiment of the present invention, when the number of blades is 2, the two blades are initially at an angle of 90 to 180 degrees, and the angle is opened upward to face the direction of the solid catalyst feed, preferably 180 degrees. The midline of the angle is consistent with the axis of the upper cylinder section; after adding a certain amount of solid catalyst, the rotating shaft is controlled to drive the two blades to rotate in opposite directions to open the space between the two blades, and the blades stop when they hit the blocking column. After all the solid catalyst falls into the reactor, the rotating shaft is controlled to drive the blades to rotate to restore the blades to the initial state.

[0042] According to one embodiment of the present invention, when the number of blades is 3 or 4, one of the angles between the two blades is initially facing the direction of the solid catalyst feed, and the midline of the angle is consistent with the axis of the upper cylinder section. After a certain amount of solid catalyst is added, the rotating shaft is controlled to drive the blades to rotate. After all the solid catalyst falls into the reactor, the rotating shaft is continued to be controlled to drive the blades to rotate until the other angle is facing the direction of the solid catalyst feed.

[0043] According to a preferred embodiment of the present invention, in step (4), after the rotating shaft rotates, nitrogen is introduced through the nitrogen purge port of the feeding device for purge, so that the solid catalyst can fully enter the reactor.

[0044] According to a preferred embodiment of the present invention, in step (4), the rotation of the rotating shaft can be electrically or manually, preferably electrically, that is, a motor is used to control the rotating shaft, thereby indirectly controlling the rotation of the blades.

[0045] The catalyst adding method of the present invention can be used for similar processes with relatively harsh requirements on catalyst addition; it can not only meet the harsh requirements of the process on catalyst conditions, but also realize intermittent catalyst addition without affecting the normal operation of the device.

[0046] Technical advantages of the present invention:

[0047] 1) Safety: Propylene dimerization requires a highly water-free and oxygen-free environment. 2 Purging can ensure that the catalyst feed is in a water-free and oxygen-free environment.

[0048] 2) Flexibility:

[0049] A) The feeding device of the present invention adopts a flange cover, the sealing plate, the rotating shaft and the blades are integrated, and the shell is similar to a sleeve. Only the flange covers at the left and right ends of the feeding device need to be opened to pull out the parts for replacement and maintenance. This method is plug-in type and can be removed for cleaning and replacement;

[0050] B) Using a specific blade structure, the amount and speed of catalyst addition can be adjusted according to needs;

[0051] C) The catalyst addition port can realize the switch function.

[0052] All publications, patent applications, patents and other references mentioned in this specification are incorporated herein by reference. Unless otherwise defined, all technical and scientific terms used in this specification have the meanings conventionally understood by those skilled in the art. In the event of a conflict, the definition in this specification shall prevail.

[0053] When this specification uses the prefix "well-known to those skilled in the art", "prior art" or similar terms to introduce materials, substances, methods, steps, devices or components, etc., the objects introduced by the prefix cover those commonly used in the art when this application is filed, but also include those that are not commonly used at present but will become recognized in the art as being suitable for similar purposes.

[0054] In the context of this specification, except for the contents explicitly described, any matters or items not mentioned are directly applicable to those known in the art without any changes. Moreover, any embodiment described herein can be freely combined with one or more other embodiments described herein, and the technical solutions or technical ideas formed thereby are regarded as part of the original disclosure or original record of the present invention, and should not be regarded as new contents not disclosed or anticipated herein, unless a person skilled in the art considers that the combination is obviously unreasonable.

[0055] The present invention will be further described below by way of examples, but are not limited thereto. BRIEF DESCRIPTION OF THE DRAWINGS

[0056] Figure 1 It is a structural schematic diagram of an implementation mode of the intermittent feeding system of the present invention.

[0057] Figure 2 It is a structural schematic diagram of an implementation mode of the feeding system of the present invention.

[0058] Figure 3 yes Figure 2 Blade cross-sectional view at AA.

[0059] Figure 4 It is a schematic structural diagram of an embodiment of a feeding device of the present invention.

[0060] Figure 5 yes Figure 4 Blade cross-sectional view at AA.

[0061] Figure 6 yes Figure 4 Horizontal section top view.

[0062] Figure 7 It is a schematic structural diagram of an embodiment of a feeding device of the present invention.

[0063] Figure 1 Mark in:

[0064] a-feeding hopper;

[0065] b-the first unloading valve;

[0066] c-feeding device;

[0067] d-the second unloading valve;

[0068] e-purge gas inlet;

[0069] f- Nitrogen purge port.

[0070] Figure 2 Mark in:

[0071] g-seal plate;

[0072] h - axis of rotation

[0073] l-Blade

[0074] m-flange cover. DETAILED DESCRIPTION

[0075] The present invention is described in detail below in conjunction with specific embodiments. It is necessary to point out that the following embodiments are only used to further illustrate the present invention and cannot be understood as limiting the scope of protection of the present invention. Some non-essential improvements and adjustments made to the present invention by those skilled in the art based on the contents of the present invention still fall within the scope of protection of the present invention.

[0076] It should also be noted that the various specific technical features described in the following specific embodiments can be combined in any suitable manner without contradiction. To avoid unnecessary repetition, the present invention will not further describe various possible combinations.

[0077] In addition, the various embodiments of the present invention may be arbitrarily combined as long as they do not violate the concept of the present invention. The technical solutions thus formed belong to part of the original disclosure of this specification and also fall within the protection scope of the present invention.

[0078] In the following examples, unless otherwise specified, the experimental methods used are all conventional methods, and the materials and reagents used can be purchased from domestic chemical companies.

[0079] Example 1

[0080] like Figure 1 As shown, an embodiment of the present invention discloses an intermittent feeding system for a solid catalyst, including a feeding barrel section, the feeding barrel section includes an upper barrel section and a lower barrel section, a feeding device c is arranged between the upper barrel section and the lower barrel section, a first unloading valve b and a second unloading valve d are respectively arranged at the top of the upper barrel section and the bottom of the lower barrel section, and a purge gas inlet e and an exhaust port are arranged on the side wall of the upper barrel section; the feeding barrel section is vertically arranged at the top of the reactor, and the bottom of the lower barrel section is connected to the feeding port at the top of the reactor through a flange.

[0081] like Figure 2 and 3 As shown, according to one embodiment of the feeding system of the present invention, the feeding device includes a housing, a rotating shaft h, blades l, a sealing plate g and a flange cover m, wherein:

[0082] The shell has a four-way tubular structure. The inner diameters of the upper and lower ports of the shell in the vertical axis direction are the same as those of the feeding barrel section, and the upper and lower ports are respectively connected to the upper barrel section and the lower barrel section. The inner diameter of the shell in the vertical axis direction is equal to the inner diameter of the shell in the horizontal axis direction. The rotating shaft h is set at a coaxial position with the horizontal axis of the shell. The left and right ports in the horizontal axis direction of the shell are sealed with flange covers m, and the rotating shaft passes through the sealing plate and the flange cover.

[0083] The blades are arranged on the rotating shaft, the number of blades is 4, the blades are rectangular and match the shape of the barrel section, the vertical length matches 1 / 2 of the inner diameter of the horizontal tube of the shell, the horizontal length matches the inner diameter of the vertical tube of the shell, the length direction of the blades is consistent with the axial direction of the rotating shaft, the blades are fixedly connected to the rotating shaft, the root part where the blades are connected to the rotating shaft has an arc transition surface, and the angle between the blades is 90°. The sealing plate is a circular flat plate, the diameter of which is equal to the inner diameter of the horizontal tube of the shell, and the structure formed by the two sealing plates and the inner wall of the horizontal tube of the shell matches the outer edge of the blade in the central horizontal cross section.

[0084] A PTFE protective edge is provided on the edge of the blade, and the width of the protective edge is 10 mm.

[0085] Four nitrogen purge ports f are arranged on the sealing plate g on one side of the feeding device, and the nitrogen purge ports are connected to the nitrogen source through a pipeline passing through a flange cover on one side. The radial distance between each nitrogen purge port and the center point of the sealing plate is 1 / 20 of the inner diameter of the tube body in the horizontal direction of the shell, and the four nitrogen purge ports are evenly distributed on the circumference with the center point of the sealing plate as the circle point. When installing the sealing plate, it is preferred to locate the two opposite nitrogen purge ports on the vertical center line of the center point of the sealing plate.

[0086] A Johnson net is arranged at the exhaust port, and the filtering accuracy of the Johnson net is 5 μm.

[0087] The specific method for adding the solid catalyst comprises the following steps:

[0088] 1. Open the first unloading valve b at the top of the upper cylinder section, and close the second unloading valve d at the bottom of the lower cylinder section;

[0089] 2. Add solid catalyst through the feeding hopper a, and then close the first discharge valve b;

[0090] 3. Open the purge gas inlet e and introduce nitrogen to replace the air;

[0091] 4. After a period of time, open the second discharge valve d;

[0092] 5. The motor controls the rotating shaft h to rotate and drive the blades to make the solid catalyst fall;

[0093] 6. Open the nitrogen purge port f and introduce nitrogen for purge to allow the solid catalyst to fully enter the reactor.

[0094] 7. After the feeding is completed, close the second unloading valve d at the bottom of the lower cylinder section, control the rotation shaft h to rotate, and make the blades in the initial position.

[0095] After the addition is completed, the propylene dimerization process in this embodiment is as follows:

[0096] The initial flow rate of the fresh propylene feed stream is 320 kg / h. After the recycled propylene stream separated from the top of the light component removal column enters the propylene buffer tank, the flow rate of the outlet stream of the propylene buffer tank is maintained at 320 kg / h. The initial flow rate of the solvent (dodecane) feed stream is 160 kg / h. After the recycled solvent stream enters the solvent feed buffer tank, the flow rate of the outlet stream of the solvent feed buffer tank is maintained at 160 kg / h.

[0097] The solvent feed stream is buffered by the solvent feed buffer tank to obtain the outlet stream of the solvent feed buffer tank and sent to the first solid-liquid reactor. The fresh propylene stream is sent to the propylene buffer tank at normal temperature and an operating pressure of 3 MPaG. The buffered propylene feed is heated to 140 °C by the propylene feed heat exchanger and then sent to the first solid-liquid reactor to contact with the supported K-Fe / K 2 CO 3 catalyst for the first polymerization reaction. The first solid-liquid reactor is filled with 30 kg of the supported K-Fe / K 2 CO 3 catalyst. Under a nitrogen atmosphere, the operating temperature of the first solid-liquid reactor is 140 °C, the operating pressure is 5 MPaG, and the space velocity is 1 h -1 . The outlet stream of the first solid-liquid reactor obtained by overflowing the material after the first polymerization reaction in the first solid-liquid reactor enters the second solid-liquid reactor.

[0098] The second solid-liquid reactor is filled with 80 kg of the supported K-Fe / K 2 CO 3 catalyst. Under a nitrogen atmosphere, the operating temperature of the second solid-liquid reactor is 150 °C, the operating pressure is 5 MPaG, and the space velocity is 0.33 h -1 . The volume ratio of the treatment capacity of the first solid-liquid reactor to that of the second solid-liquid reactor is 0.5. The product after the second polymerization reaction is filtered by the filter element arranged inside the discharge port to obtain the outlet stream of the second solid-liquid reactor and sent to the separation unit (including a three-stage separation rectification column).

[0099] The outlet stream of the second solid-liquid reactor from the second solid-liquid reactor enters the light component removal column with an operating pressure of 0.55 MPaG and an operating temperature of 180 °C for the first-stage light component separation. The recycled propylene stream separated from the top is recycled as a raw material. The product stream after the first-stage light component separation obtained at the bottom of the column enters the heavy component removal column. In the heavy component removal column, the recycled solvent stream is separated and recycled under a negative pressure condition (50 KPaA). The crude product stream separated by the light and heavy component removal columns enters the product separation column, and product separation is carried out at an operating pressure of 0.2 MPa(A) and an operating temperature of 65 °C to obtain the 4M1P product stream. (All of the above three-stage separation rectification columns use 6 mm diameter metal wire mesh Raschig rings as high-efficiency packing, and the column height is 20 m)

[0100] The accumulated C6 olefin products can be separated by the above three stages to achieve a propylene single-pass conversion rate of 45%, a dimerization product selectivity of 75%, and a 4-methyl-1-pentene selectivity of 70%, thereby obtaining a 4-methyl-1-pentene product with a purity of 97.5%.

[0101] The existing propylene dimerization catalyst feeding technology adopts in-situ configuration, and the catalyst is directly poured into the reactor at the reserved opening on the top of the reactor. First, it will inevitably cause catalyst contamination and is very dangerous; second, the reserved opening is small, which may easily cause poor catalyst feeding.

[0102] The feeding system and method of the present application have the following advantages:

[0103] (1) The catalyst is prevented from contacting with air and oxygen, thus extending the service life of the catalyst;

[0104] (2) A flanged cylinder section is provided on the top of the reactor;

[0105] (3) The catalyst retention area is set in the middle of the cylinder; the upper part of the cylinder is connected to N 2 Purge and exhaust pipeline; the lower part is directly connected to the reactor.

[0106] (4) The catalyst feeding port is configured as a plug-in type rotating feeding port.

[0107] Example 2

[0108] like Figure 4-6 As shown, according to one embodiment of the feeding system of the present invention, the feeding device includes a housing, a rotating shaft h, blades l, a sealing plate g and a flange cover m.

[0109] The shell has a four-way tubular structure. The diameters of the upper and lower ports of the shell in the vertical axis direction are the same as those of the feeding barrel section, and the upper and lower ports are respectively connected to the upper barrel section and the lower barrel section. The inner diameter of the shell in the vertical axis direction is equal to the inner diameter of the shell in the horizontal axis direction. The rotating shaft h is set at the coaxial position of the shell's horizontal axis. The left and right ports in the horizontal axis direction of the shell are sealed with flange covers m, and the rotating shaft passes through the sealing plate and the flange cover.

[0110] The blades are arranged on the rotating shaft, and there are 4 blades. The blades are semicircular in shape matching the barrel section, and their radius matches 1 / 2 of the inner diameter of the horizontal tube body of the shell. The length direction of the blades is consistent with the axial direction of the rotating shaft. The blades are fixedly connected to the rotating shaft, and the root part where the blades are connected to the rotating shaft has an arc transition surface. The angle between each blade is 90°. The sealing plate is a curved surface matching the shape of the blades. The vertical center line of the sealing plate is a vertical straight line, and the horizontal center line of the sealing plate is a semicircular arc. The radius of the semicircle matches the radius of the blade, and its projection in the vertical direction coincides with the vertical cross-sectional shape of the horizontal tube body of the shell. The inner side of the central horizontal cross-section of the structure surrounded by the two sealing plates matches the outer edge of the blade.

[0111] A PTFE protective edge is provided on the edge of the blade, and the width of the protective edge is 10 mm.

[0112] Four nitrogen purge ports f are arranged on the sealing plate g on one side of the feeding device, and the nitrogen purge ports are connected to the nitrogen source through a pipeline passing through a flange cover on one side. The radial distance between each nitrogen purge port and the center point of the sealing plate is 1 / 20 of the inner diameter of the tube body in the horizontal direction of the shell, and the four nitrogen purge ports are evenly distributed on the circumference with the center point of the sealing plate as the circle point. When installing the sealing plate, it is preferred to locate the two opposite nitrogen purge ports on the vertical center line of the center point of the sealing plate.

[0113] A Johnson net is arranged at the exhaust port, and the filtering accuracy of the Johnson net is 5 μm.

[0114] Example 3

[0115] like Figure 7 As shown, according to one embodiment of the feeding system of the present invention, the feeding device includes a housing, a rotating shaft h, blades l, a sealing plate g and a flange cover m.

[0116] The tube body in the horizontal axis direction of the shell is a cylindrical structure, the inner diameter of the tube body in the vertical axis direction of the shell remains unchanged, and the outside has a structure with gradually increasing diameters from the upper and lower ends. The tube body in the horizontal axis direction of the shell and the tube body in the vertical axis direction of the shell are interconnected, the inner diameters of the upper and lower ports of the tube body in the vertical axis direction of the shell are the same as the inner diameter of the feeding barrel section, and the upper and lower ports are respectively connected to the upper barrel section and the lower barrel section, the inner diameter of the tube body in the vertical axis direction of the shell is equal to the inner diameter of the tube body in the horizontal axis direction of the shell, the rotating shaft h is set at a coaxial position with the horizontal axis of the shell, the left and right ports in the horizontal axis direction of the shell are sealed with a flange cover m, and the rotating shaft passes through the sealing plate and the flange cover.

[0117] The blades are arranged on the rotating shaft, and there are 4 blades. The blades are semicircular in shape matching the barrel section, and their radius matches 1 / 2 of the inner diameter of the horizontal tube body of the shell. The length direction of the blades is consistent with the axial direction of the rotating shaft. The blades are fixedly connected to the rotating shaft, and the root part where the blades are connected to the rotating shaft has an arc transition surface. The angle between each blade is 90°. The sealing plate is a curved surface matching the shape of the blades. The vertical center line of the sealing plate is a vertical straight line, and the horizontal center line of the sealing plate is a semicircular arc. The radius of the semicircle matches the radius of the blade, and its projection in the vertical direction coincides with the vertical cross-sectional shape of the horizontal tube body of the shell. The inner side of the central horizontal cross-section of the structure surrounded by the two sealing plates matches the outer edge of the blade.

[0118] A PTFE protective edge is provided on the edge of the blade, and the width of the protective edge is 10 mm.

[0119] Four nitrogen purge ports f are arranged on the sealing plate g on one side of the feeding device, and the nitrogen purge ports are connected to the nitrogen source through a pipeline passing through a flange cover on one side. The radial distance between each nitrogen purge port and the center point of the sealing plate is 1 / 20 of the inner diameter of the tube body in the horizontal direction of the shell, and the four nitrogen purge ports are evenly distributed on the circumference with the center point of the sealing plate as the circle point. When installing the sealing plate, it is preferred to locate the two opposite nitrogen purge ports on the vertical center line of the center point of the sealing plate.

[0120] A Johnson net is arranged at the exhaust port, and the filtering accuracy of the Johnson net is 5 μm.

Claims

1. An intermittent feeding system for a solid catalyst, comprising a feeding barrel section, the feeding barrel section comprising an upper barrel section and a lower barrel section, a feeding device is arranged between the upper barrel section and the lower barrel section, a first unloading valve and a second unloading valve are arranged at the top of the upper barrel section and the bottom of the lower barrel section respectively, and a purge gas inlet and an exhaust port are arranged on the side wall of the upper barrel section; the feeding barrel section is connected to the feeding port of the reactor.

2. The feeding system according to claim 1, Features: The feeding device includes a shell, a rotating shaft, blades, a sealing plate and a flange cover, wherein the shell has a four-way tubular structure, the inner diameters of the upper and lower ports of the tube body in the vertical axis direction of the shell are the same as the inner diameter of the feeding barrel section, and the upper and lower ports are respectively connected to the upper barrel section and the lower barrel section, the inner diameter of the tube body in the vertical axis direction of the shell is less than or equal to the inner diameter of the tube body in the horizontal axis direction of the shell, the rotating shaft is arranged at a coaxial position of the horizontal axis of the shell, the blades are arranged on the rotating shaft, the length direction of the blades is consistent with the axial direction of the rotating shaft, the sealing plates are vertically arranged at positions on both sides of the rotating shaft and the blades, the structure surrounded by two sealing plates or the structure surrounded by two sealing plates and the inner wall of the tube body in the horizontal direction of the shell has the inner side of the central horizontal cross-section matched with the outer edge of the blade, the left and right ports in the horizontal axis direction of the shell are sealed with flange covers, and the rotating shaft passes through the sealing plates and the flange covers.

3. The feeding system according to claim 1, Features: The blades are configured to be semicircular, circular or rectangular in shape to match the vertical cross-sectional dimensions of the tube in the horizontal direction of the shell; and / or the number of the blades is 1 to 4; Preferably, When the number of blades is 1, the blade and the rotating shaft are an integrated structure, and the center line of the blade is the rotating shaft; the blade is circular or rectangular. When it is circular, its diameter matches the inner diameter of the horizontal tube of the shell; when it is rectangular, its vertical length matches the inner diameter of the horizontal tube of the shell, and its horizontal length matches the inner diameter of the vertical tube of the shell; When the number of blades is 2, two rotating shafts are arranged side by side and close to each other, and each rotating shaft is fixedly connected to a blade; the blade is semicircular or rectangular. When it is semicircular, its radius matches 1 / 2 of the inner diameter of the horizontal tube body of the shell; when it is rectangular, its vertical length matches 1 / 2 of the inner diameter of the horizontal tube body of the shell, and its horizontal length matches the inner diameter of the vertical tube body of the shell; When the number of blades is 3 or 4, the blades are fixedly connected to the rotating shaft, and the angles between the blades are preferably the same; the blades are semicircular or rectangular. When they are semicircular, their radius matches 1 / 2 of the inner diameter of the horizontal tube body of the shell; when they are rectangular, their vertical length matches 1 / 2 of the inner diameter of the horizontal tube body of the shell, and their horizontal length matches the inner diameter of the vertical tube body of the shell.

4. The feeding system according to claim 3, Features: When the number of blades is 1, a blocking column is set on the inner wall of one side of the sealing plate, and the angle between the line connecting the center point of the bottom surface of the blocking column and the center point of the sealing plate and the center line of the vertical direction on the sealing plate is 25° to 45°; When the number of blades is 2, two baffle columns are set on the inner wall of one side of the sealing plate, and the angle between the line connecting the center point of the bottom surface of each baffle column and the center point of the sealing plate and the center line of the vertical direction of the sealing plate is 25°~45°, and the two baffle columns are located on both sides of the vertical line of the center point of the sealing plate.

5. The feeding system according to claim 3, Features: When the number of blades is greater than 1, the root portion where the blade is connected to the rotating shaft has an arc transition surface; and / or, When the blade is semicircular or circular, the sealing plate is a curved surface matching the blade shape, the vertical centerline of the sealing plate is a vertical straight line, the horizontal centerline of the sealing plate is an arc, and its projection in the vertical direction coincides with the vertical cross-sectional shape of the horizontal tube of the shell; the outer edge of the sealing plate and the inner wall of the horizontal tube of the shell are in a gap-type fit; When the blade is rectangular, the sealing plate is a circular flat plate, and its diameter is equal to the inner diameter of the tube body in the horizontal direction of the shell; the outer edge of the sealing plate and the inner wall of the tube body in the horizontal direction of the shell are in a gap-type fit.

6. The feeding system according to claim 2, Features: A nitrogen purge port is provided on a sealing plate on one side of the feeding device, and the nitrogen purge port is connected to a nitrogen source through a pipeline passing through a flange cover on one side; When the number of blades is 1 or 2, one nitrogen purge port is provided, and the radial distance between the nitrogen purge port and the center point of the sealing plate is 1 / 20 to 1 / 8 of the inner diameter of the tube body in the horizontal direction of the shell; When the number of blades is 3, three nitrogen purge ports are provided, wherein the radial distance between each nitrogen purge port and the center point of the sealing plate is 1 / 20 to 1 / 8 of the inner diameter of the tube body in the horizontal direction of the shell, and preferably, the radial distance between each nitrogen purge port and the center point of the sealing plate is the same; preferably, the three nitrogen purge ports are evenly distributed on the circumference of a circle with the center point of the sealing plate as the center point; When the number of blades is 4, 4 nitrogen purge ports are provided, wherein the radial distance between each nitrogen purge port and the center point of the sealing plate is 1 / 20 to 1 / 8 of the inner diameter of the tube body in the horizontal direction of the shell, and preferably, the radial distance between each nitrogen purge port and the center point of the sealing plate is the same; preferably, the 4 nitrogen purge ports are evenly distributed on the circumference of a circle with the center point of the sealing plate as the center.

7. The feeding system according to any one of claims 2 to 6, Features: A PTFE protective edge is provided on the edge of the blade, preferably, the width of the protective edge is 5 to 10 mm; A Johnson net is arranged at the exhaust port. Preferably, the filtering accuracy of the Johnson net is 5 to 50 μm.

8. The feeding system according to claim 1, Features: The feeding cylinder section is vertically arranged on the top of the reactor, and the bottom of the lower cylinder section is connected with the feeding port on the top of the reactor through a flange.

9. A method for adding a solid catalyst in a propylene dimerization process, using the feeding system according to any one of claims 1 to 8, The following steps are involved: (1) Open the first feed valve at the top of the upper cylinder section and add solid catalyst through the feed hopper; (2) After the solid catalyst falls into the feeding device, close the first feeding valve; (3) introducing nitrogen gas into the purge gas inlet for purge; (4) After the purging is completed, the second discharge valve at the bottom of the lower cylinder section is opened, and the rotating shaft rotates to allow the solid catalyst to enter the reactor.

10. The feeding method according to claim 9, Features: In step (4), after the rotating shaft rotates, nitrogen is introduced through the nitrogen purge port of the feeding device for purging; and / or, The rotating shaft is rotated electrically or manually, preferably electrically.

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