Elastic gland device and up-flow hydrogenation reactor

Abstract

The invention discloses an elastic gland device and an up-flow hydrogenation reactor, and relates to the field of petrochemical equipment, the elastic gland device comprises an upper fixing ring, a lower fixing ring and a gland body, the upper fixing ring and the lower fixing ring are fixedly arranged in the up-flow hydrogenation reactor, and a cavity used for installing the gland body is formed between the upper fixing ring and the lower fixing ring; the gland body comprises a lower grating disc, an intercepting ball layer, an upper grating disc and an elastic piece which are sequentially arranged from bottom to top, and the lower grating disc, the intercepting ball layer and the upper grating disc can float up and down in a cavity between the upper fixing ring and the lower fixing ring under the impact force of materials and the elastic force of the elastic piece. The problem that the gland in the up-flow fixed bed reactor is easy to block can be solved.

Description

Technical Field

[0001] The present invention relates to the field of petrochemical equipment, and specifically to an elastic gland device and an up-flow hydrotreating reactor. Background Art

[0002] The market demand for clean oil products is increasing rapidly. Therefore, the lightening and upgrading of heavy oil are important tasks that need to be solved urgently at present. The hydrotreating technology is an effective means to solve the above problems. Through hydrogenation, impurities such as sulfur, nitrogen, metals, resins, and carbon residue in oil products can be effectively removed, and unsaturated hydrocarbons can be hydrogenated into saturated hydrocarbons. According to the reactor type, the hydrogenation process can be divided into fixed-bed hydrogenation process, suspension-bed hydrogenation process, and ebullated-bed hydrogenation process, among which the fixed-bed hydrogenation process is the most widely used.

[0003] According to the feed direction of the fixed-bed hydrotreating reactor, it can be divided into two forms: up-flow (down-feed) and down-flow (up-feed) fixed-bed hydrotreating reactors. The up-flow fixed-bed reactor has certain advantages in the oil product hydrogenation process. The up-flow fixed-bed reactor can handle various types of oil products. For example, in inferior oil product residue and coal liquefied oil, due to the high impurity content, it is easy to cause hydrogenation catalyst poisoning or catalyst pore blockage and rapid deactivation, and the impurities may block the bed layer, resulting in a rapid increase in pressure drop, leading to a deterioration of the reactor operating conditions and even inability to operate normally. If the up-flow hydrogenation reaction process is adopted to make the gas-liquid flow upward in parallel, it can cause the expansion of the catalyst bed layer, increase the void fraction of the bed layer, and avoid the blockage of the catalyst bed layer. However, although the expanded bed layer can avoid bed layer blockage, it will cause catalyst disturbance, resulting in catalyst blockage of the gland grid, leading to an increase in pressure drop, and even causing the shutdown of the device in severe cases.

[0004] In the prior art, the Chinese invention patent with the application number 201811644438.8 discloses an up-flow reactor and its application. The up-flow reactor includes a reactor shell, and a catalyst bed support grid and a catalyst bed are sequentially arranged in the reactor shell along the material flow direction. An elastic support layer is arranged at the lower part and / or the upper part of the catalyst bed. The elastic support layer includes a plastic elastomer bed layer and a porcelain ball support layer. The plastic elastomer bed layer includes a plurality of plastic elastomer units, and the plastic elastomer units include granular bodies prepared from elastic materials. There are voids between the plastic elastomer units and inside the units as channels for fluid flow. In this invention, the plastic elastomer bed layer in the up-flow reactor can deform synchronously with the expansion and contraction of the catalyst bed layer, prevent the increase of bed layer pressure drop caused by particle wear during the floating process of the catalyst, and ensure the long-term stable operation of the up-flow reactor.

[0005] The Chinese invention patent with the application number CN201811644425.0 discloses a fixed-bed up-flow reactor and its application. Specifically, it discloses that the reactor includes a reactor shell, and a support grid, a lower catalyst bed, a sliding grid layer, an upper catalyst bed, and a gland grid are arranged in the reactor shell along the material flow direction; a reaction material inlet is arranged at the bottom of the reactor shell, a reaction material outlet is arranged at the top of the reactor shell, and the sliding grid layer includes an upper sliding grid and a lower sliding grid; the reactor can also be provided with a catalyst dust filter layer and a gland. The fixed-bed up-flow reactor can effectively control the expansion and contraction degree of the catalyst bed, prevent particle abrasion caused by the floating of the catalyst, and can reduce the generation of dust while protecting the catalyst.

[0006] In summary, among the current technical solutions, some devices and structures are disclosed to control the expansion and contraction degree of the catalyst bed, thereby reducing the generation of powder. However, the problem of gland blockage still exists in the up-flow fixed-bed reactor. Summary of the Invention

[0007] The present invention aims to provide an elastic gland device and an up-flow hydrogenation reactor to improve the problem of gland blockage in the up-flow fixed-bed reactor.

[0008] To solve the above technical problems, the specific solution adopted by the present invention is: an elastic gland device, including an upper fixing ring, a lower fixing ring, and a gland body. The upper fixing ring and the lower fixing ring are fixedly arranged in the up-flow hydrogenation reactor, and a cavity for installing the gland body is formed between the upper fixing ring and the lower fixing ring; the gland body includes a lower grid plate, an interception ball layer, an upper grid plate, and an elastic member arranged in sequence from bottom to top. The lower grid plate, the interception ball layer, and the upper grid plate can float up and down in the cavity between the upper fixing ring and the lower fixing ring under the impact force of the material and the elastic force of the elastic member.

[0009] As a further optimization of the above technical solution: both the lower grid plate and the upper grid plate include a plurality of wire bars arranged in parallel at intervals and connection bars connecting the plurality of wire bars. The wire bars are regular triangular prisms;

[0010] One edge of the wire bars in the lower grid plate is vertically downward, and the connection points of the connection bars and the wire bars are located on the opposite side surfaces of the edge. A gap with a width gradually decreasing from bottom to top is formed between adjacent wire bars;

[0011] One edge of the wire bars in the upper grid plate is vertically upward, and the connection points of the connection bars and the wire bars are located on the opposite side surfaces of the edge. A gap with a width gradually increasing from bottom to top is formed between adjacent wire bars.

[0012] As a further optimization of the above technical solution: the minimum gap between adjacent wire bars and the minimum gap between adjacent wire bars are both greater than the catalyst diameter by 2 - 5 mm.

[0013] As a further optimization of the above technical solution: the filaments of the upper grille plate are vertically distributed with the filaments of the lower grille plate.

[0014] As a further optimization of the above technical solution: the opening ratio of the lower grille plate is not less than 10%, and the opening ratio of the upper grille plate is not less than 1%.

[0015] As a further optimization of the above technical solution: the elastic member is a wire mesh layer composed of multiple layers of wire meshes.

[0016] As a further optimization of the above technical solution: the thickness of the elastic member is 10 - 30 mm.

[0017] As a further optimization of the above technical solution: the elastic member is made of stainless steel.

[0018] As a further optimization of the above technical solution: there are several stacked intercepting balls in the intercepting ball layer, and the size of the intercepting balls is Φ3 - Φ5 mm.

[0019] An up - flow hydro - reactor, which has the above - mentioned elastic gland device, and the elastic gland device is arranged above the catalyst bed layer of the up - flow hydro - reactor.

[0020] Compared with the prior art, the beneficial effects of the present invention are as follows: the present invention provides an elastic gland device for an up - flow hydro - reactor. By combining the intercepting balls with the elastic fixing device, the problem of gland blockage in the up - flow fixed - bed reactor is effectively improved. By combining the grille plate with the intercepting ball layer and using the void flow channels between the spheres to block the catalyst, the problem that the catalyst blocks the gland plate in the up - flow reactor is effectively avoided.

[0021] The present invention adopts the principle of dynamic characteristics to improve the original fixed - type grille plate gland into a dynamic gland with a movable intercepting ball layer. While improving the interception efficiency, it will not increase the pressure drop of the gland for the reactor.

[0022] Using an elastic gland device can increase the operation flexibility of the gas - liquid in the reactor and meet the interception of the catalyst under different operation load conditions.

[0023] Using an elastic gland device can effectively prevent the catalyst from blocking the gland. On the one hand, it can elastically fix the catalyst bed layer, and on the other hand, use the rebounding force of the gland to shake off the catalyst particles attached to it, reducing the probability of blockage. During the rebounding process of the gland, it can form a disturbance to the intercepting balls, increasing the dropping efficiency of the catalyst.

[0024] In the lower grille tray, a gap with a width gradually decreasing from bottom to top is formed between adjacent wire strips, and in the upper grille tray, a gap with a width gradually increasing from bottom to top is formed between adjacent wire strips, so that the plane of the lower grille tray faces upward, the plane of the upper grille tray faces downward, and the area formed between the upper grille tray and the lower grille tray is easy to clamp the intercepted balls. At the same time, the inclined surface at the lower part of the lower grille tray can also block the catalyst to a certain extent, reducing the amount of catalyst flowing into the intercepted ball layer. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 is a schematic structural view of the present invention;

[0026] Figure 2 is a schematic structural view of the gland body in the present invention;

[0027] Figure 3 is a schematic cross-sectional view of the lower grille tray, the intercepted ball layer, and the upper grille tray;

[0028] Figure 4 is a top view of the lower grille tray;

[0029] Reference numerals: 1, lower grille tray; 2, intercepted ball layer; 3, upper grille tray; 4, elastic member; 5, catalyst bed; 6a, wire strip; 6b, wire strip; 7, connecting strip; 8, reactor inner wall; 9, lower fixing ring; 10, upper fixing ring. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0030] The technical solutions of the present invention will be further elaborated in detail below in conjunction with the accompanying drawings and specific embodiments. For the parts not detailedly recorded and disclosed in the following embodiments of the present invention, they should all be understood as the prior art known or should be known to those skilled in the art.

[0031] As Figure 1 , Figure 2 shown, the present invention discloses an elastic gland device, including an upper fixing ring 10, a lower fixing ring 9, and a gland body. The upper fixing ring 10 and the lower fixing ring 9 are fixedly arranged in an upflow hydrogenation reactor, and a cavity for installing the gland body is formed between the upper fixing ring 10 and the lower fixing ring 9.

[0032] Specifically, the upper fixing ring 10 and the lower fixing ring 9 are respectively fixed to the reactor inner wall 8 of the hydrogenation reactor by welding. The upper fixing ring 10 and the lower fixing ring 9 have a certain distance in the vertical direction, and this distance is consistent with the thickness of the gland body. The gland body is arranged between the upper fixing ring 10 and the lower fixing ring 9. The lower part of the gland body is supported on the lower fixing ring 9, and the upper part is limited and constrained by the upper fixing ring 10.

[0033] The gland body includes a lower grille plate 1, an intercepting ball layer 2, an upper grille plate 3, and an elastic member 4 arranged in sequence from bottom to top. The lower grille plate 1, the intercepting ball layer 2, and the upper grille plate 3 can float up and down in the cavity between the upper fixing ring 10 and the lower fixing ring 9 under the impact force of the material and the elastic force of the elastic member 4.

[0034] The diameter of the gland body is slightly smaller than the inner diameter of the up-flow hydrogenation reactor, so that there is a certain gap between the gland body and the inner wall of the reactor. This gap is smaller than the diameter of the intercepting balls in the intercepting ball layer 2, so as to prevent the intercepting balls in the intercepting ball layer 2 from entering the gap between the gland body and the inner wall of the reactor or entering the reactor through the gap during the up-and-down floating process.

[0035] The lower grille plate 1 is located at the bottom of the gland body, and the edge of the lower grille plate 1 is supported on the lower fixing ring 9. The lower grille plate 1 can support the intercepting ball layer 2, the upper grille plate 3, and the elastic member 4 above, and preliminarily intercept the catalyst in the catalyst bed layer 5.

[0036] As Figure 3 、 4 shown, the lower grille plate 1 includes a plurality of wire bars 6a arranged in parallel at intervals, and a connecting bar 7 connecting the plurality of wire bars 6a. The cross-section of the wire bar 6a is triangular, and the whole is a regular triangular prism.

[0037] One of the edges of the wire bar 6a in the lower grille plate 1 is vertically downward, and the connection point of the connecting bar 7 and the wire bar 6a is located on the side opposite to this edge. Therefore, the downward edges of the respective wire bars 6a are parallelly distributed, the sides of the respective wire bars 6a connected to the connecting bar 7 form a plane, and the two sides of the respective wire bars 6a not connected to the connecting bar 7 are inclined downward, and a gap with a width gradually decreasing from bottom to top is formed between adjacent wire bars 6a.

[0038] The minimum gap between adjacent wire bars 6a is greater than the catalyst diameter by 2 - 5 mm to ensure that the catalyst in the disturbed state will not be stuck in the slits of the lower grille plate 1 to form a blockage. It should be noted that since the gap between adjacent wire bars 6a is strip-shaped, the gap between adjacent wire bars 6a is the slit between adjacent wire bars 6a; the gap between adjacent wire bars 6a gradually decreases from bottom to top, and the minimum gap between adjacent wire bars 6a refers to the distance between the uppermost ends of adjacent wire bars 6a.

[0039] Preferably, the minimum gap between adjacent wire bars 6a is greater than the catalyst diameter by 3 - 5 mm.

[0040] During the hydrogenation reaction process, the materials in the reactor and the catalyst particles escaping from the catalyst bed layer 5 flow upward together and downward to the lower grid plate 1. Since the catalyst is solid particles with a specific gravity greater than that of the liquid materials in the hydrogenation reactor, and the greater the mass, the greater the inertia. The momentum of the catalyst in the reactor is much greater than that of the liquid materials. Therefore, when the liquid materials enter the gradually decreasing gap from bottom to top, they are easily blocked by the inclined side of the wire strip 6a and change direction, thus entering the gap between adjacent wire strips 6a. The catalyst in the hydrogenation reactor is not likely to change direction and thus difficult to enter the gap between adjacent wire strips 6a. The catalyst contacts the inclined side of the wire strip 6a, loses the upward inertial force and falls downward due to the downward momentum and gravity, thus returning to the catalyst bed layer 5. It can be understood that even under the driving of the materials flowing upward from bottom to top in the reactor, if the catalyst cannot completely return to the catalyst bed layer 5, the amount of catalyst entering the lower grid plate 1 can be reduced due to the blockage of the inclined side of the wire strip 6a.

[0041] The number of connecting strips 7 is multiple and they are distributed in parallel at intervals, and the distance between adjacent connecting strips 7 is the same. The width of the connecting strip 7 can be adjusted according to the actual situation. In this embodiment, the width of the connecting strip 7 is smaller than the width of the side of the wire strip 6a. The connecting strip 7 and the wire strip 6a are distributed in a crisscross pattern to form through holes. In this embodiment, the connecting strip 7 and the wire strip 6a are perpendicular to each other. The opening ratio of the through holes on the lower grid plate 1 is 10% - 50%. The opening ratio in this embodiment is 40%.

[0042] It should be noted that the cross-section of the up-flow hydrogenation reactor is mostly circular. Therefore, the cross-section of the gland body is also a corresponding circular shape. Figure 4 The top view of the shown lower grid plate 1 only shows the connection relationship between the connecting strip 7 and the wire strip 6a schematically.

[0043] Similarly, the upper grid plate 3 includes multiple wire strips 6b arranged in parallel at intervals, and connecting strips 7 connecting the multiple wire strips 6b. The cross-section of the wire strip 6b is also triangular, and the whole is a regular triangular prism shape.

[0044] One of the edges of the wire strip 6b is vertically upward, and the connection point of the connecting strip 7 and the wire strip 6b is located on the side opposite to this edge. Therefore, the upward edges in each wire strip 6b are parallelly distributed, and the sides of each wire strip 6b connected to the connecting strip 7 form a plane, and the gap between adjacent wire strips 6b gradually increases from bottom to top. The minimum gap between adjacent wire strips 6b is greater than the diameter of the catalyst by 2 - 5 mm.

[0045] The connecting strip 7 and the wire strip 6b in the upper grid plate 3 are distributed in a crisscross pattern to form through holes. The opening ratio of the upper grid plate 3 is not greater than that of the lower grid plate 1. Preferably, the opening ratios of the upper grid plate 3 and the lower grid plate are the same.

[0046] The slit width of the upper grid plate 3 is consistent with that of the lower grid plate 1, and the wire strips of the upper grid plate 3 and the wire strips of the lower grid plate 1 are vertically distributed, which can make the through holes of the upper grid plate 3 and the through holes of the lower grid plate 1 misaligned and reduce catalyst overflow.

[0047] A gap with a width gradually increasing from bottom to top is formed between adjacent wire strips 6b in the upper grid plate 3, so the smallest gap between adjacent wire strips 6b is at the bottom. This arrangement can prevent the catalyst from easily entering the gap formed between adjacent wire strips 6b, and the reaction material flowing into the gap can flow out upward through the gradually increasing gap.

[0048] Between the upper grid plate 3 and the lower grid plate 1 is the interception ball layer 2, in which a number of stacked interception balls are arranged, the plane formed by the wire strips 6a and the connecting strips 7 in the lower grid plate 1 faces upward, and the plane formed by the wire strips 6b and the connecting strips 7 in the upper grid plate 3 faces downward, and the interception ball layer 2 is located between the upper grid plate 3 and the lower grid plate 1, and the interception ball layer 2 can be clamped by the planes of the upper grid plate 3 and the lower grid plate 1.

[0049] The interception ball layer 2 is the main action area, which comprehensively intercepts the catalyst leaked after being intercepted by the lower grid plate 1. The interception balls can be selected to be porcelain balls or stainless steel balls, preferably porcelain balls.

[0050] In this embodiment, a porcelain ball is selected as the intercepting ball. The size of the intercepting ball may be Φ3-Φ5 mm. In this embodiment, a porcelain ball of Φ3 mm is selected as the intercepting ball.

[0051] By combining the upper grid plate 3, the lower grid plate 1 and the intercepting ball layer 2, the catalyst is blocked by the gap flow channel between the intercepting balls, which can effectively avoid the problem of catalyst blocking the gland plate in the upstream reactor. Since the gap flow channel formed by the intercepting balls is a tortuous flow channel, the reacting materials can flow out of the flow channel, but the catalyst overflowing from the catalyst bed 5 will be blocked by the tortuous flow channel in the flow channel, so the intercepting ball layer 2 has a good interception effect.

[0052] The catalyst intercepted by the interception ball layer 2 enters the upper grid plate 3 along with the material. The upper grid plate 3 can not only play the role of finally intercepting the catalyst, but also fix the interception ball layer 2, thereby limiting the interception balls in the interception ball layer 2 from detaching from the interception ball layer 2 under the impact of the material.

[0053] The upper part of the upper grid plate 3 is an elastic member 4. The elastic member 4 in this embodiment is a multi-layer wire mesh structure. The thickness of the wire mesh layer can be 10-30 mm, specifically 10 mm, 15 mm, 20 mm, 25 mm, 30 mm, etc. In this embodiment, a 20 mm thick elastic wire mesh layer is selected. The wire mesh material is stainless steel and has a certain elasticity as a whole. It is pressed tightly by the upper grid plate 33, the lower grid plate 11 and the intercepting ball layer 22.

[0054] By combining the upper grid plate, the lower grid plate and the intercepting ball layer, a new type of elastic gland device is formed to replace the original grid gland that is easy to clog. The problem of catalyst clogging the grid gland in the upflow reactor can be effectively avoided. The present invention uses the principle of spherical accumulation to produce flow channel interception and the principle of improving the fixed device into a movable part to effectively block the catalyst without increasing the pressure drop caused by the gland as much as possible. At the same time, the use of an elastic gland increases the operational flexibility, ensures that no clogging occurs under different operating loads, and maintains the stable and smooth operation of the reactor.

[0055] The present invention also discloses an upflow hydrogenation reactor, which has the elastic gland device mentioned above, and the elastic gland device is arranged on the upper part of the catalyst bed 5 of the upflow hydrogenation reactor.

[0056] An upper fixing ring 10 and a lower fixing ring 9 are welded to the inner wall of the upflow hydrogenation reactor. The upper fixing ring 10 and the lower fixing ring 9 are both arranged on the upper part of the catalyst bed 5. A cavity for installing a gland body is formed between the upper fixing ring 10 and the lower fixing ring 9. The elastic gland body installed between the upper fixing ring 10 and the lower fixing ring 9 covers the upper part of the catalyst bed 5.

[0057] During the reaction, the lower grid plate 1, the interception ball layer 2 and the upper grid plate 3 can float up and down in the cavity between the upper fixed ring 10 and the lower fixed ring 9 under the impact force of the material and the elastic force of the elastic member 4. As the catalyst bed 5 expands, the elastic gland body is subjected to the material impact force (including the flow impact of the material flowing from bottom to top in the reactor and the expansion impact of the catalyst) and moves upward. At this time, the elastic member 4 is compressed, and the volume of the catalyst bed 5 can be increased, which alleviates the increase in the pressure drop of the catalyst bed 5. At the same time, since the height between the upper fixed ring 10 and the lower fixed ring 9 is consistent with the height of the gland body, the degree of compression of the elastic member 4 is limited, which limits the expansion degree of the catalyst bed 5 and can also prevent the catalyst in the catalyst bed 5 from floating too strongly to a certain extent and cause catalyst wear. The compressed elastic member 4 releases elastic potential energy and has a downward elastic force, which pushes the lower grid plate 1, the interception ball layer 2 and the upper grid plate 3 downward under the action of the elastic force. At this time, the interception ball in the interception ball layer 2 is disturbed during the movement, and the active interception ball can increase the efficiency of catalyst falling.

[0058] In the present invention, through the elastic gland device, on the one hand, the catalyst bed 5 can be elastically fixed, and on the other hand, the catalyst intercepted in the void flow channels of the intercepting balls and in the voids between the upper grid plate 3 and the lower grid plate 1 can be shaken off under the action of the resilience of the gland, reducing the probability of blockage.

[0059] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. An elastic gland device, characterized in that: It includes an upper fixing ring (10), a lower fixing ring (9) and a gland body. The upper fixing ring (10) and the lower fixing ring (9) are fixedly arranged in an up-flow hydrogenation reactor. A cavity for installing the gland body is formed between the upper fixing ring (10) and the lower fixing ring (9). The gland body includes a lower grid plate (1), an interception ball layer (2), an upper grid plate (3) and an elastic member (4) which are arranged in sequence from bottom to top. The lower grid plate (1), the interception ball layer (2) and the upper grid plate (3) can float up and down in the cavity between the upper fixing ring (10) and the lower fixing ring (9) under the impact force of the material and the elastic force of the elastic member (4).

2. The elastic capping device according to claim 1, characterized in that: Both the lower grid plate (1) and the upper grid plate (3) include multiple wire bars arranged in parallel at intervals and connection bars (7) connecting the multiple wire bars. The wire bars are regular triangular prisms. One edge of the wire bar (6a) in the lower grid plate (1) is vertically downward. The connection point of the connection bar (7) and the wire bar (6a) is located on the opposite side of this edge. A gap with a width gradually decreasing from bottom to top is formed between adjacent wire bars (6a). One edge of the wire bar (6b) in the upper grid plate (3) is vertically upward. The connection point of the connection bar (7) and the wire bar (6b) is located on the opposite side of this edge. A gap with a width gradually increasing from bottom to top is formed between adjacent wire bars (6b).

3. The elastic gland device according to claim 2, wherein: The minimum gap between adjacent wire bars (6a) and the minimum gap between adjacent wire bars (6b) are both greater than the catalyst diameter by 2 - 5 mm.

4. The elastic gland device according to claim 2, characterized in that: The wire bars (6a) of the upper grid plate (3) and the wire bars (6b) of the lower grid plate (1) are perpendicularly distributed.

5. An elastic gland device according to claim 1, characterized in that: The upper grid plate (3) and the lower grid plate (1) have the same porosity, which is 10% - 50%.

6. The elastic gland device according to claim 1, characterized in that: The elastic member (4) is a wire mesh layer composed of multiple layers of wire meshes.

7. An elastic gland device according to claim 6, characterized in that: The thickness of the elastic member (4) is 10 - 30 mm.

8. An elastic gland device according to claim 6, characterized in that: The elastic member (4) is made of stainless steel.

9. The elastic gland device according to claim 1, characterized in that: There are several stacked interception balls in the interception ball layer (2). The size of the interception balls is Φ3 - Φ5 mm.

10. An upflow hydrogenation reactor, characterized in that, This up-flow hydrogenation reactor is provided with an elastic gland device as described in Claim 1, and the elastic gland device is arranged above the catalyst bed layer (5) of the up-flow hydrogenation reactor.

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