A new type of cyclone quench box

Abstract

The present invention discloses a novel cyclone quench box, which comprises a top plate, a bottom plate and a mixing box formed between the two. A hollow annular feed boss is arranged on the top plate, a feed throttling hole is opened in the middle of the top plate, a first through hole is opened in the middle of the annular feed boss, and a feed swirl plate is radially arranged between the outside of the first through hole and the inner wall of the annular feed boss; a second through hole is opened in the middle of the mixing box, a rectifying ring plate is further arranged inside the mixing box, and a mixing swirl plate is radially arranged between the outside of the second through hole and the inner wall of the rectifying ring plate; rectifying ring plate throttling holes are opened on the side wall of the rectifying ring plate; small holes are opened on the bottom plate. The quench box provided by the present invention is provided with a feed swirl plate; a mixing swirl plate is added in the mixing box, the flow path length is increased, the contact time between the gas phase and the liquid phase is prolonged, the mixing and heat transfer effects are improved, and the radial temperature difference at the inlet of the lower catalyst bed layer is reduced.

Description

Technical Field

[0001] The present invention belongs to the technical field of petroleum refining and chemical equipment, and particularly relates to a novel cyclone quench box. Background Art

[0002] Hydrogenation reactions are widespread in petroleum refining and petrochemical processes, such as hydrocracking, hydrofining reactions, etc. Hydrogenation reactors provide a place for hydrogenation reactions. All hydrogenation reactors will release a large amount of reaction heat during operation. Excessive temperature will affect the performance of the catalyst. Therefore, in order to ensure the performance of the catalyst and the stable and safe operation of the device, the bed temperature of the catalyst must be effectively controlled; otherwise, when the heat released by the reaction is much greater than the heat removed from the device, a huge heat accumulation will occur in the device in a short time, resulting in a jump in the temperature inside the reactor, heat imbalance in the system, and reaching an uncontrollable level, which is the so-called "temperature runaway" phenomenon. The temperature runaway phenomenon will cause various adverse effects, such as significantly reducing the selectivity, activity, and service life of the catalyst, etc. Severe temperature runaway will even directly lead to the sintering and deactivation of the catalyst; the premature deactivation of the catalyst will not only increase the use cost of the catalyst, but also the frequent replacement of the catalyst will greatly shorten the operation cycle of the device, thereby having a negative impact on the overall economic benefits of the refinery. Therefore, when the heat released by the reaction is large, it is very necessary to take appropriate measures to remove the heat from the reactor. The commonly used industrial solution is to divide the catalyst into several bed layers when loading the catalyst, and a quench box is arranged between two adjacent catalyst bed layers to remove the heat released by the reaction, thereby reducing the temperature of the reaction stream. The number of bed layers and their respective heights are determined by the temperature rise curve, generally divided into 2 - 6 bed layers, and each bed layer is about 3 - 6 meters high. Arranging a quench box between adjacent catalyst bed layers can achieve the full mixing of the reaction heat stream and the coolant and make it flow evenly into the next catalyst bed layer, enabling the next catalyst bed layer to continue to undergo hydrogenation reactions.

[0003] Currently, the mixing mechanism of the coolant and the reaction heat stream in the quench box generally includes throttling, collision, and swirl, and thus baffle quench boxes, impact quench boxes, and cyclone quench boxes are designed.

[0004] Patent document US3723072 discloses a typical baffle - type quench box. The high - temperature fluid from the upper catalyst bed enters the quench box body through an annular plate with evenly distributed circular small holes under the guidance of the flow channel. The cold hydrogen enters the box body from the circular inlet at the center of the top plate. There is an annular mixing box in the central area of the circular box body. The gas - liquid two - phase completes the preliminary mixing and heat transfer in the annular mixing box. Then, the gas - liquid mixture enters the conveying channel under the guidance of the baffle and undergoes further turbulent flow in the channel. After a reciprocating folding process, uniform mixing of the gas - liquid two - phase is achieved. However, this type of quench box is large in volume, and the numerous baffles will increase the flow resistance of the fluid, resulting in excessive loss of fluid kinetic energy, a large pressure drop, and poor overall economic efficiency.

[0005] Patent document US3502445 is representative of the impact - type quench box developed by Union Oil Company of the United States. It mainly includes an upper top plate, a central box body, and a lower bottom plate. The upper top plate is provided with two symmetric circular throttle holes directly above the central box body. At symmetric positions on both sides of the central box body, there is a rectangular rectifying baffle with evenly distributed circular small holes, and the bottom plate is provided with evenly distributed circular sieve holes. The reaction fluid from the previous bed layer is blocked by the top plate of the quench box. Most of it first stays on the top plate and then is brought into the central box body by the high - speed sprayed gas - phase cold medium through the throttle holes on the top plate. Due to the sudden reduction in the flow - through area at the throttle holes, the mixed fluid produces a throttling effect and impacts the bottom plate at a very high speed, generating splashes and vortices, enhancing the disturbance effect of the fluid. Then, the fluid is further accelerated at the constricted flow channel in the central box body. The high - speed flowing mixed fluid collides violently in the central box body and then flows out of the central box body in two paths. When it encounters the rectifying baffle, part of the mixed fluid flows out through the openings on the baffle, and the other part of the mixed fluid turns to the outer area of the central box body because it hits the non - opening area of the baffle. Finally, all the fluid flows to the next catalyst bed layer through the sieve holes opened on the bottom plate. This type of quench box was once widely used in petroleum refining, but in devices with heavy - crude oil feed and a high gas - liquid ratio, there is a large radial temperature difference at the outlet of the catalyst bed layer, sometimes even reaching 10 - 20 °C.

[0006] Patent document CN2448440Y discloses a cyclone - type quench box, which is composed of a cold hydrogen pipe, a baffle, a semi - circular mixing channel, a tangential guide pipe, and a mixing box. The hot reaction fluid from the upper catalyst bed layer and the cold hydrogen are preliminarily mixed on the baffle, and then enter a mixing box with a diameter much smaller than that of the quench box through the semi - circular mixing channel. After swirling and mixing in the mixing box, it undergoes a re - folding and mixing process through the throttle holes at the lower part of the mixing box. Finally, the mixed fluid reaches the sieve plate, and the fluid is evenly distributed through the sieve plate and flows to the next catalyst bed layer. Due to the short contact time of the mixed fluid in the mixing chamber in this structure, the temperature of the reaction fluid flowing out from the sieve plate is uneven, which in turn affects the performance of the catalyst.

[0007] In view of this, it is very necessary to provide a quench box with uniform mixing of cold and hot logistics, small temperature difference between bed layers, and simple structure. Summary of the Invention

[0008] Aiming at the deficiencies of the existing technology, the purpose of the present invention is to provide a new type of swirl quench box, so as to make the mixing effect of the cold medium and the hot reaction material flow more ideal and make the temperature distribution of the mixed material flow more uniform.

[0009] In order to achieve the above purpose, the present invention adopts the following technical solutions:

[0010] A new type of swirl quench box includes a top plate, a bottom plate which are separated up and down, and a mixing box formed between the two. The top plate, the mixing box and the bottom plate are all centrosymmetrically arranged; a hollow annular feed boss is arranged on the top plate, a feed throttle hole is opened in the middle of the top plate, a first through hole corresponding to the feed throttle hole is opened in the middle of the annular feed boss, and a feed swirl plate is radially arranged between the outside of the first through hole and the inner wall of the annular feed boss; a second through hole corresponding to the feed throttle hole is opened in the middle of the mixing box, and a rectifying ring plate in the shape of a hollow cylinder is further arranged inside the mixing box. A mixing swirl plate is radially arranged between the outside of the second through hole and the inner wall of the rectifying ring plate; a rectifying ring plate throttle hole is opened on the side wall of the rectifying ring plate; mixing box inner sieve holes are opened on the part of the bottom plate between the inner side of the rectifying ring plate and the outside of the second through hole, and mixing box outer sieve holes are opened on the part of the bottom plate outside the rectifying ring plate;

[0011] Wherein, the height of the feed swirl plate is higher than the height of the annular feed boss, and a liquid retaining circular plate is fixedly installed on the upper surface of the feed swirl plate.

[0012] As a preference of the technical solution of the present invention, the upper end of the rectifying ring plate is fixedly installed at the bottom of the top plate, and the lower end of the rectifying ring plate is fixedly installed at the upper part of the bottom plate.

[0013] As a preference of the technical solution of the present invention, the feed swirl plate is an arc-shaped vertical plate.

[0014] As a preference of the technical solution of the present invention, the mixing swirl plate is an arc-shaped vertical plate.

[0015] As a preference of the technical solution of the present invention, the arc bending directions of the feed swirl plate and the mixing swirl plate are opposite.

[0016] As a preference of the technical solution of the present invention, the shape of the rectifying ring plate throttle hole is one or more of triangle, square or circle.

[0017] Preferably, the number of throttle holes in the rectifying ring plate is 48 to 80, and the number of feed swirl plates and mixing swirl plates is 4 to 8 each.

[0018] Preferably, the aperture ratios of the sieve holes inside and outside the mixing box are both 5 to 20%, and the aperture sizes are both 6 to 18 mm.

[0019] Preferably, the aperture density of the sieve holes inside the mixing box is less than that of the sieve holes outside the mixing box.

[0020] Preferably, the top plate and the bottom plate are both fixedly installed on the reactor wall.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] A novel cyclone quench box provided by the present invention mainly includes components such as a top plate, an annular feed boss, a feed swirl plate, a mixing swirl plate, and a bottom plate, with a novel and simple structure. In the quench box, the hot reaction fluid from the upper catalyst bed layer and the added cold medium first gather on the top plate and are pre-mixed. When the liquid phase accumulates to a certain thickness on the top plate, it crosses the annular feed boss, is accelerated by the feed swirl plate, and enters the mixing box through the throttle hole. Compared with the conventional quench box, due to the addition of the feed swirl plate on the top plate and the mixing swirl plate in the mixing box, the flow path length is increased, the contact time between the gas phase and the liquid phase is greatly extended, the mixing and heat transfer effects are improved, thereby reducing the radial temperature difference at the inlet of the lower catalyst bed layer and being beneficial to the full play of the catalyst performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 is a schematic structural diagram of a novel cyclone quench box of the present invention;

[0024] Figure 2 is Figure 1 the A - A sectional view in

[0025] Figure 3 is Figure 1 the B - B sectional view in

[0026] Figure 4 is a three-dimensional schematic diagram of the upper part structure of a novel cyclone quench box of the present invention;

[0027] Figure 5 is a three-dimensional schematic diagram of the lower part structure of a novel cyclone quench box of the present invention.

[0028] Among them, 1. Top plate; 2. Liquid retaining circular plate; 3. Annular feed boss; 4. Feed throttle hole; 5. Feed swirling plate; 6. Rectifying ring plate; 7. Rectifying ring plate throttle hole; 8. Sieve holes inside the mixing box; 9. Mixing box; 10. Mixing swirling plate; 11. Sieve holes outside the mixing box; 12. Bottom plate; 13. Reactor wall. Specific embodiments

[0029] Next, in combination with the embodiments of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0030] Please refer to Figures 1 to 5 , the present invention provides a new type of swirling quenching box, including a top plate 1 and a bottom plate 12 which are separated up and down, and a mixing box 9 formed therebetween. The top plate 1, the mixing box 9 and the bottom plate 12 are all symmetrically arranged about the center; a hollow annular feed boss 3 is provided on the top plate 1, a feed throttle hole 4 is opened in the middle of the top plate 1, and a first through hole (not labeled in the figure) corresponding to the feed throttle hole 4 is opened in the middle of the annular feed boss 3. A feed swirling plate 5 is radially arranged between the outside of the first through hole and the inner wall of the annular feed boss 3; a second through hole (not labeled in the figure) corresponding to the feed throttle hole 4 is opened in the middle of the mixing box 9. A hollow cylindrical rectifying ring plate 6 is further provided inside the mixing box 9. A mixing swirling plate 10 is radially arranged between the outside of the second through hole and the inner wall of the rectifying ring plate 6; a rectifying ring plate throttle hole 7 is opened on the side wall of the rectifying ring plate 6; sieve holes 8 inside the mixing box are opened on the part of the bottom plate 12 between the inner side of the rectifying ring plate 6 and the outside of the second through hole, and sieve holes 11 outside the mixing box are opened on the part of the bottom plate 12 outside the rectifying ring plate 6;

[0031] Among them, the height of the feed swirling plate 5 is higher than the height of the annular feed boss 3, and a liquid retaining circular plate 2 is fixedly installed on the upper surface of the feed swirling plate 5.

[0032] In the above technical solution, the quench box of the present invention is generally centrosymmetric. The first through hole, the feed throttle hole 4 and the second through hole are all arranged in the exact middle of the quench box and communicate with each other, facilitating the flow of the hot and cold mixed material stream; through the arrangement of the annular feed boss 3, and defining that the height of the feed swirler 5 is higher than the height of the annular feed boss 3, a flow passage is formed between the annular feed boss 3 and the liquid retaining circular plate 2, facilitating the hot and cold material streams to overflow into the mixing box 9 through the annular feed boss after being fully mixed on the top plate 1; the setting of the feed swirler 5 serves to guide and accelerate the hot and cold mixed material; the setting of the feed throttle hole 4 serves to sharply increase the flow rate of the hot and cold mixed material through throttling; on the part of the bottom plate 12 between the inner side of the rectifying ring plate 6 and the outer side of the second through hole, a mixing box inner sieve hole 8 is provided, and on the part of the bottom plate 12 outside the rectifying ring plate 6, a mixing box outer sieve hole 11 is provided. With such a setting, no holes are provided in the area corresponding to the bottom plate 12 below the second through hole (corresponding area C). After the hot and cold mixed material enters through the second through hole, it will bounce and splash on the bottom plate 12, generating a vortex. The liquid phase material stream is carried by the gas phase material stream and broken into small droplets, and then further swirls and mixes along the mixing swirler 10. A part of the mixed material stream flows out of the quench box approximately uniformly through the mixing box inner sieve hole 8 (corresponding area D); another part of the mixed material stream impacts the rectifying ring plate 6 at a high speed, rushes out of the mixing box 9 through the rectifying ring plate throttle hole 7 on the rectifying ring plate 6, is more evenly distributed on the opening area F outside the mixing box 9, and finally flows out of the quench box through the mixing box outer sieve hole 11 on the area F.

[0033] In some embodiments, both the top plate 1 and the bottom plate 12 are fixedly installed on the reactor wall 13. By setting like this, the fixation of the quench box can be achieved.

[0034] In some embodiments, the upper end of the rectifying ring plate 6 is fixedly installed at the bottom of the top plate 1, and the lower end of the rectifying ring plate 6 is fixedly installed at the upper part of the bottom plate 12. It can be understood that its fixed installation form can be various common forms such as welding, which is a conventional choice for those skilled in the art.

[0035] In some embodiments, the feed swirler 5 is an arc-shaped vertical plate; in some embodiments, the mixing swirler 10 is an arc-shaped vertical plate.

[0036] In some embodiments, the arc bending directions of the feed swirler 5 and the mixing swirler 10 are opposite. With such a setting, the mixing effect of the hot and cold mixed material can be further enhanced.

[0037] In some embodiments, the shape of the throttle holes 7 of the rectifying ring plate is one or more of triangular, square or circular; preferably, it is circular. It can be understood that the size of the throttle holes 7 of the rectifying ring plate can be opened accordingly as required, and no specific limitation is made thereto in this embodiment.

[0038] In some embodiments, the number of the throttle holes 7 of the rectifying ring plate is 48 to 80; it can be understood that the number of the throttle holes 7 of the rectifying ring plate can be flexibly selected according to actual needs; preferably, the number of the throttle holes 7 of the rectifying ring plate is 80.

[0039] The number of the feed swirler plates 5 and the mixing swirler plates 10 is 4 to 8. It can be understood that the number of the feed swirler plates 5 can be 4, 5, 6, 7 or 8; the number of the mixing swirler plates 10 can also be 4, 5, 6, 7 or 8; the specific number of both can be flexibly selected according to actual needs; preferably, the number of the feed swirler plates 5 and the mixing swirler plates 10 is equal, both being 8.

[0040] In some embodiments, the opening ratios of the sieve holes 8 inside the mixing box and the sieve holes 11 outside the mixing box are both 5 to 20%, and the opening sizes are both 6 to 18 mm. It can be understood that both the opening ratio and the opening size can be set according to actual needs.

[0041] In some embodiments, the opening density of the sieve holes 8 inside the mixing box is less than that of the sieve holes 11 outside the mixing box. With such a setting, the sieve holes 8 inside the mixing box with a small opening density can slow down the downward flow of the fluid out of the mixing box and prolong the mixing time; the sieve holes 11 outside the mixing box with a large opening density can make the fluid flow more smoothly to the next bed layer and reduce the pressure drop.

[0042] Further refer to Figures 1 to 3, a specific description of the entire working process and principle of the quench box of the present invention: After the quench box is assembled and fixedly installed on the reactor wall 13 as described above, it starts to work. The hot reaction material flow from the upper catalyst bed layer above the quench box and the added cold medium first gather on the top plate 1 and are pre-mixed. When the liquid phase accumulates to a certain thickness on the top plate 1, it crosses the annular feed boss 3. Under the action of the feed swirler 5, the mixed material flow starts to rotate and accelerate, and then enters the mixing box 9 through the feed throttle hole 4. Due to sudden throttling, the flow rate surges, and the mixed material flow violently impacts the unopened area C in the center of the mixing box 9, rebounds and splashes on the bottom plate 12, generating vortices; the liquid phase material flow is carried by the gas phase material flow and broken into small droplets, and then further swirls and mixes along the mixing swirler 10. Part of the mixed material flow flows out of the quench box approximately evenly through the sieve holes 8 in the mixing box on the opened area D in the mixing box; another part of the mixed material flow impacts the rectifying ring plate 6 at a high speed and rushes out of the mixing box 9 through the rectifying ring plate throttle hole 7 on the rectifying ring plate 6, and is more evenly distributed on the opened area F outside the mixing box, and finally flows out of the quench box through the sieve holes 11 outside the mixing box on the area F.

[0043] The following further elaborates on a novel swirl quench box of the present invention in conjunction with specific embodiments.

[0044] Embodiment 1

[0045] In this specific embodiment, a novel swirl quench box is provided, which includes a top plate 1 and a bottom plate 12 that are separated up and down, and a mixing box 9 formed therebetween. The top plate 1, the mixing box 9, and the bottom plate 12 are all symmetrically arranged about the center; a hollow annular feed boss 3 is provided on the top plate 1, a feed throttle hole 4 is opened in the middle of the top plate 1, a first through hole corresponding to the feed throttle hole 4 is opened in the middle of the annular feed boss 3, and a feed swirler 5 is radially arranged between the outside of the first through hole and the inner wall of the annular feed boss 3; a second through hole corresponding to the feed throttle hole 4 is opened in the middle of the mixing box 9, and a rectifying ring plate 6 in the shape of a hollow cylinder is further provided inside the mixing box 9. A mixing swirler 10 is radially arranged between the outside of the second through hole and the inner wall of the rectifying ring plate 6; a rectifying ring plate throttle hole 7 is opened on the side wall of the rectifying ring plate 6; sieve holes 8 in the mixing box are opened on the part of the bottom plate 12 between the inside of the rectifying ring plate 6 and the outside of the second through hole, and sieve holes 11 outside the mixing box are opened on the part of the bottom plate 12 outside the rectifying ring plate 6. The quench box is fixedly installed on the reactor wall 13 through both the top plate 1 and the bottom plate 12;

[0046] The height of the feed swirler 5 is higher than the height of the annular feed boss 3, and a liquid blocking circular plate 2 is fixedly installed on the upper surface of the feed swirler 5.

[0047] In this specific embodiment, the upper end of the rectifying ring plate 6 is fixedly installed at the bottom of the top plate 1, and the lower end of the rectifying ring plate 6 is fixedly installed at the upper part of the bottom plate 12.

[0048] In this specific embodiment, both the feed swirl plate 5 and the mixing swirl plate 10 are arc-shaped vertical plates, and the bending directions of their arcs are opposite.

[0049] In this specific embodiment, the shape of the orifice of the rectifying ring plate throttle hole 7 is circular, and the number is 80.

[0050] In this specific embodiment, the numbers of both the feed swirl plate 5 and the mixing swirl plate 10 are 8.

[0051] In this specific embodiment, the opening size of the sieve holes 8 inside the mixing box is 8 mm, and the opening ratio is 7%; the opening size of the sieve holes 11 outside the mixing box is 8 mm, and the opening ratio is 12%.

[0052] Since the novel swirl quenching box adds the feed swirl plate 5 on the top plate 1, and adds the mixing swirl plate 10 and the rectifying ring plate 6 inside the mixing box, under the combined action of these three, not only the residence time of the mixed fluid in the novel swirl quenching box is greatly prolonged, but also the mixed fluid has multiple throttling, collisions and swirls. These are all beneficial to the full mixing and heat exchange of the hot reaction fluid and the added cold medium, and are evenly distributed to the lower catalyst bed.

[0053] The present invention uses the above embodiments to illustrate the technical concept of the present invention, but the present invention is not limited to the above embodiments, that is, it does not mean that the present invention must rely on the above embodiments to be implemented. Those skilled in the art should understand that any improvement to the present invention, the equivalent replacement of individual raw materials of the products of the present invention, the addition of auxiliary components, and the selection of specific methods, etc., all fall within the protection scope and the disclosure scope of the present invention.

Claims

1. A new type of cyclone quench box, characterized in that, It includes a top plate (1), a bottom plate (12) with an upper and lower separation setting, and a mixing box (9) formed therebetween. The top plate (1), the mixing box (9), and the bottom plate (12) are all symmetrically arranged about the center; a hollow annular feed boss (3) is provided on the top plate (1), a feed throttling hole (4) is opened in the middle of the top plate (1), a first through hole corresponding to the feed throttling hole (4) is opened in the middle of the annular feed boss (3), and a feed swirling plate (5) is radially arranged between the outside of the first through hole and the inner wall of the annular feed boss (3); a second through hole corresponding to the feed throttling hole (4) is opened in the middle of the mixing box (9), and a hollow cylindrical rectifying ring plate (6) is further provided inside the mixing box (9), and a mixing swirling plate (10) is radially arranged between the outside of the second through hole and the inner wall of the rectifying ring plate (6); a rectifying ring plate throttling hole (7) is opened on the side wall of the rectifying ring plate (6); mixing box inner sieve holes (8) are opened on the part of the bottom plate (12) between the inside of the rectifying ring plate (6) and the outside of the second through hole, and mixing box outer sieve holes (11) are opened on the part of the bottom plate (12) outside the rectifying ring plate (6); Among them, the height of the feed swirling plate (5) is higher than the height of the annular feed boss (3), and a liquid blocking circular plate (2) is fixedly installed on the upper surface of the feed swirling plate (5).

2. A novel cyclone quenching box according to claim 1, characterized in that, The upper end of the rectifying ring plate (6) is fixedly installed at the bottom of the top plate (1), and the lower end of the rectifying ring plate (6) is fixedly installed at the upper part of the bottom plate (12).

3. A novel cyclone quench box according to claim 1, characterized in that, The feed swirling plate (5) is an arc-shaped vertical plate.

4. A novel cyclone quench box according to claim 1, characterized in that, The mixing swirling plate (10) is an arc-shaped vertical plate.

5. A novel swirl quenching box according to claim 4, characterized in that, The arc bending directions of the feed swirling plate (5) and the mixing swirling plate (10) are opposite.

6. A novel cyclone quench box according to claim 1, characterized in that, The shape of the rectifying ring plate throttling hole (7) is one or more of a triangle, a square, or a circle.

7. A novel cyclone quench box according to claim 1, characterized in that, The number of the rectifying ring plate throttling holes (7) is 48 - 80, and the numbers of the feed swirling plate (5) and the mixing swirling plate (10) are both 4 - 8.

8. A novel cyclone quench box according to claim 1, characterized in that, The opening rates of the mixing box inner sieve holes (8) and the mixing box outer sieve holes (11) are both 5 - 20%, and the opening sizes are both 6 - 18 mm.

9. A novel cyclone quenching box according to claim 8, characterized in that, The opening density of the mixing box inner sieve holes (8) is less than the opening density of the mixing box outer sieve holes (11).

10. A novel swirl quenching box according to any one of claims 1 to 9, characterized in that, The top plate (1) and the bottom plate (12) are both fixedly installed on the reactor wall (13).

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