CN108114670B

CN108114670B - Sleeve type impact reducing and flow equalizing disc

Info

Publication number: CN108114670B
Application number: CN201611084901.9A
Authority: CN
Inventors: 彭德强; 王璐瑶; 孟凡飞; 陈新; 刘杰
Original assignee: China Petroleum and Chemical Corp; Sinopec Fushun Research Institute of Petroleum and Petrochemicals
Current assignee: China Petroleum and Chemical Corp; Sinopec Fushun Research Institute of Petroleum and Petrochemicals
Priority date: 2016-11-30
Filing date: 2016-11-30
Publication date: 2021-12-07
Anticipated expiration: 2036-11-30
Also published as: CN108114670A

Abstract

The invention discloses a sleeve type impact reduction flow equalizing disc. The sleeve type impact reduction and flow equalization plate comprises a tower tray and a plurality of chimney type distributors arranged on the tower tray; the chimney type distributor comprises a downcomer and a shock-absorbing cylinder arranged at the upper end of the downcomer; the impact reduction cylinder and the downcomer are both of cylindrical structures with openings at two ends, the impact reduction cylinder and the downcomer are arranged up and down, and the diameter of the impact reduction cylinder is larger than that of the downcomer. The invention relates to a flow reducing and equalizing disc, which is a new inner member added to a reactor and arranged in an idle space of an upper end socket of a hydrogenation reactor or at the upper end of a cylinder body of the hydrogenation reactor. The flow reducing and equalizing disc can reduce the strong impact force formed by the residual kinetic energy when fluid enters the reactor, and eliminate the wave pushing phenomenon of the inclined flow line formed when the central point enters the liquid layer of the distribution disc. The sleeve type impact reduction and flow equalization disc is suitable for all hydrogenation reactors, and is particularly suitable for hydrogenation reactors with large liquid-gas ratio and large scale.

Description

Sleeve type impact reducing and flow equalizing disc

Technical Field

The invention relates to a sleeve type impact reduction flow equalizing disc, and belongs to the field of chemical equipment. The sleeve type impact reduction flow equalizing disc is a newly added inner component of the reactor. The sleeve type impact reduction and flow equalization disc is suitable for various hydrogenation reactors, and is particularly suitable for hydrogenation reactors with large liquid-gas ratio and large scale.

Background

In recent years, with the rapid development of national economy and the enhancement of environmental awareness, the requirements on the quality and the environmental protection of petrochemical products are higher and higher. In order to meet the requirements of processing sulfur-containing crude oil, meet the increasing demands of chemical raw materials and improve the quality of products, the importance and the role of hydrogenation technology in the oil refining industry are increasing. In a hydrogenation device, raw oil which is used as a key device of a hydrogenation reactor is mixed with hydrogen according to a certain proportion, and the reactions such as refining, cracking and the like are completed under the action of a hydrogenation catalyst. Whether the hydrogenation reaction in the hydrogenation reactor can be stably operated or not, whether the hydrogenation catalyst can fully exert the function or not, whether the product quality can reach high quality or not, and the method depends on the uniformity of the distribution of gas and liquid in a catalyst bed layer to a great extent. Whether the gas and liquid are uniformly distributed in the catalyst bed layer or not is closely related to the design of the internal components of the hydrogenation reactor. In other words, the performance of the internals directly affects the catalyst life, product quality and the operation period of the apparatus, i.e. the effect obtained by using a set of excellent-performance internals in the hydrogenation process is in no way inferior to that obtained by using a more active catalyst. Therefore, the research and engineering development of the internal components of the hydrogenation reactor at home and abroad always pay attention to and continuously update the internal components of the reactor so as to obtain better effect.

The hydrogenation reactor internals include inlet diffuser, gas-liquid distribution disc, scale depositing basket, catalyst bed support, cold hydrogen tank, outlet collector, inert ceramic ball, etc. the most important internals directly concerning the catalyst utilization efficiency are gas-liquid distribution disc and cold hydrogen tank.

In the processes of gas-liquid-solid three-phase hydrocracking and hydrodesulfurization reactions, a fixed bed hydrogenation reactor is widely used, and a gas-liquid distributor is one of the most key internal components of the fixed bed hydrogenation reactor. The gas-liquid distributor has the function of distributing, mixing and uniformly spraying gas-liquid two-phase raw materials on the surface of the catalyst bed layer, and improving the flowing state of a liquid phase in the catalyst bed layer.

The gas-liquid distributor has macroscopic uniformity and microscopic uniformity for the distribution of the reaction materials. A plurality of gas-liquid distributors are mounted on the tray in an array to form a distribution tray. The amount of liquid phase flowing through each distributor is the same as the volume of gas, ensuring "uniform" coverage of the catalyst bed by the material, defined as the macroscopic uniformity of the gas-liquid distributor. Achieving a high macroscopic uniformity of liquid distribution is difficult because the distribution trays are assembled in blocks due to the increasing diameter of the hydrogenation reactor at present, and the level of the distribution plates cannot be accurately guaranteed. Typically, installation errors will cause the distributor plate surface to be horizontally inclined at 1/8-1/2 degrees with the maximum inclination being 3/2 degrees. Even if the distribution tray is highly level at the beginning of installation, the distribution tray face loses its levelness due to the combined action of thermal expansion and material impact load during operation. Therefore, the distributor structure is required to realize the homogeneity of liquid phase macroscopic distribution.

The liquid is distributed over the bed catalyst by a distributor. The catalyst bed layer has no blank area which is not covered by liquid, so that the complete coverage of the catalyst bed layer by the material is ensured, and the microscopic uniformity of the gas-liquid distributor is realized. It is characterized by that it can reflect the liquid distribution effect of local zone of reactor bed layer.

The fixed bed hydrogenation reactor is a trickle bed reactor. The reactants flow downwardly in parallel in a gas-liquid two-phase fashion through a fixed catalyst bed. The liquid phase flows downward in a stream as the dispersed phase, while the gas phase, which is the continuous phase, flows downward co-currently with the liquid phase. The liquid phase wets the catalyst particles as it flows over the surface of the catalyst particles and the reaction takes place on the wetted catalyst particles, so that the effective wetting rate of the catalyst has a very important influence on the overall reaction rate. When the liquid-phase material enters the catalyst bed layer, the uneven distribution of the liquid-phase material forms channeling or bias flow on the catalyst bed layer, so that part of the catalyst cannot be wetted or the wetting effect is poor, the performance of the part of the catalyst cannot be exerted, and the product quality is influenced.

The hydrogenation process is an exothermic reaction, and uneven material distribution can cause severe reaction at the part with good catalyst wetting effect and generate more heat; i.e. the radial temperature difference affecting the reactor. When the radial temperature difference is large, the local temperature of the catalyst is higher, the reaction rate is higher, the effect superposition of the two effects can form hot spots, the performance of the catalyst is inactivated prematurely, the performance of the catalyst is damaged, even coking and hardening of a part of regions of the catalyst can be caused, the material can not flow normally, and the catalyst below the hardening region can not play a role because the fixed bed hydrogenation reactor is in a trickle bed flow state, so that the service life of the catalyst and the start-up period of the device are greatly reduced. The local hardening also causes the pressure drop of a catalyst bed layer to rise, the operation pressure of the reactor has to be increased for the continuous operation, and the energy consumption is increased; when the pressure drop is increased too fast to reach the designed value of the reactor, the reactor has to be shut down abnormally, the head skimming treatment is carried out, the maintenance cost is paid, and meanwhile, the catalyst is lost and wasted due to the sieving. Therefore, in a fixed bed hydrogenation reactor, the uniformity of liquid phase material distribution is very important.

The hydrogenation reactor feeds materials at the center of the top of the reactor, and although an inlet diffuser is arranged, the residual kinetic energy of material conveying can generate strong impact force; another flow state characteristic of central position feeding is that the streamline of material formation in reactor head space is the slope, and the liquid phase that has kinetic energy produces "pushing away unrestrained" phenomenon to the liquid layer on the top distributor tray, brings unfavorable entry condition for the distributor that relies on the tray levelness, even the best distributor of performance, under the liquid layer condition of the different degree of depth, also can't realize evenly distributed material, and radial difference in temperature enlarges inevitable.

The gas-liquid distribution plate is composed of a gas-liquid distributor arranged on a distribution plate, and has the main function of uniformly distributing liquid-phase reactants on a catalyst bed layer so as to ensure that all catalysts in the reactor can obtain uniform wetting degree, so that all the catalysts have similar catalytic efficiency, and the integral production efficiency of the reactor is effectively improved. In addition, the liquid phase reactant is uniformly distributed on the section of the whole catalyst bed layer, and the generation of 'hot spots' in the catalyst bed layer can be reduced, namely, the excessive radial temperature difference in the reactor is avoided, so that the coking and the inactivation of the catalyst are effectively inhibited, and the service life of the catalyst and the operation period of the reactor are prolonged. However, the gas-liquid distributor widely applied in the domestic hydrogenation field still has the defects of weak tower plate inclination resistance and poor liquid dispersion performance.

The study on the distribution uniformity of liquid in a fixed bed reactor at home and abroad has been for more than 50 years, and many researchers find that the initial distribution of the liquid on a catalyst bed layer is an important factor influencing the overall distribution uniformity of the catalyst bed layer, because single-strand liquid usually needs 4-5 times of the diameter of the reactor to realize uniform distribution on the whole bed layer.

The gas-liquid distributor is an important internal member in the fixed bed oxygen adding reactor, and the main function of the gas-liquid distributor is to provide a mixing and interaction place for gas-liquid two-phase fluid, so that the liquid is broken into liquid drops which are dispersed into gas flow and fall onto the filler along with the gas flow to form initial distribution of the liquid on the filler bed layer. The uniformity of initial liquid distribution directly influences the wetting degree and the use efficiency of downstream catalysts, if the gas-liquid distributor is unreasonable in design, the distribution effect of reaction raw materials is poor, the non-uniformity of hydrogenation reaction in a catalyst bed layer can be caused, the radial temperature difference is overlarge, the utilization rate and the service life of the catalysts are reduced, and even the quality of products cannot meet the requirements.

Along with the improvement of environmental awareness of people in recent years, the worldwide demand for clean fuels is more and more urgent, and new and higher requirements are put forward on the product quality of a hydrogenation reactor. The uniformity of the distribution of the reaction raw materials on the catalyst bed layer determines whether the hydrogenation reactor can realize stable operation or not to a great extent and the quality of the product can reach high quality, so the requirements on the performance of the gas-liquid distributor are higher and higher.

The gas-liquid distributor plays a very important role in the stable operation of the fixed bed oxygen adding reactor and the quality of the hydrogenation products, so the research on the structure and the performance of the gas-liquid distributor arouses the interests of a plurality of experts and scholars, and is also valued by main petroleum refining companies and scientific research institutions at home and abroad. Domestic units such as China petrochemical engineering construction company, Fushun petrochemical research institute and Luoyang petrochemical engineering company, and foreign units such as British Petroleum company (BP), Union Oil company (Union Oil), Texaco (Texaco), Oil products around the globe company (UOP), Chevrong Company (CHEVRON), Shell company (SHELL) have been devoting great attention to the development and application of gas-liquid distributors, and various gas-liquid distributors with different styles have been developed. Different gas-liquid distributors have different methods for achieving macroscopic distribution uniformity and microscopic distribution uniformity. The main classification according to its action mechanism is three: overflow type, suction type, and a mixed type of the two. Their structures and working mechanisms are different from each other, and their micro-distribution uniformity is also very different.

Generally speaking, according to the liquid dispersion mechanism, in the overflow type, suction type and mixed type three-type gas-liquid distribution discs with overflow and suction functions, the suction type gas-liquid distributor can disperse liquid into liquid drops with smaller particle size due to better liquid crushing performance, and under the action of the suction type gas-liquid distributor, the distribution uniformity of the liquid on a catalyst bed layer is better than that of the other two types, such as the combined oil type gas-liquid distributor widely applied in the domestic oxygenation field at present. However, since the combined oil type gas-liquid distributor adopts the same gas-liquid inlet, the area of the gas inlet will change along with the fluctuation of the liquid level, so as to cause the change of the gas velocity and the liquid suction capacity, when the gas-liquid distribution disk has a certain inclination, the gas-liquid distributors at different horizontal heights will have different gas inlet areas and liquid suction capacities, so that the liquid distribution of the gas-liquid distribution disk is not uniform enough, that is, the anti-column plate inclination capacity of the combined oil type gas-liquid distributor is not strong. In addition, some recent research reports show that the combined oil type gas-liquid distributor has a relatively serious central confluence phenomenon, and the distribution uniformity of the liquid is not ideal enough.

In recent years, with the increasing demand of domestic markets for high-quality distillate oil, together with the increasingly strict environmental regulations around the world and the global popularization and application of clean fuels, the traditional oil refining technology needs to be upgraded and upgraded for technical improvement. The technical level of the hydrogenation process mainly depends on the advancement of the catalyst performance, and the exertion of the catalyst performance greatly depends on the advancement and reasonableness of the internal structure of the reactor. One of the key technologies is that the reactor must have good initial distribution of liquid and gas and bed-to-bed redistribution to achieve the maximum utilization rate of the catalyst, otherwise, the production of ultra-low sulfur diesel oil is impossible. In order to realize the economic scale and the improvement of the manufacturing capacity of hydrogenation equipment, the size of a hydrogenation reactor is being increased, the diameter of the reactor is continuously increased, and the requirement on the reactant flow distribution effect of the components in the reactor is higher and higher.

At present, the heterogeneous condition of distribution exists to different degrees in present hydrogenation ware gas-liquid distributor home and abroad, and if domestic wide use be bubble cap type distributor, or improved generation bubble cap distributor, there is obvious inhomogeneous condition in gas-liquid distribution performance, and this distributor is based on the suction principle: the liquid phase is entrained during gas phase baffling, and liquid phase distribution is realized.

Bubble cap type dispensers rely primarily on the suction of the gas phase against the liquid phase on the dispensing tray to overcome the dispensing plate mounting tilt and maintain the uniformity of the liquid macro-distribution. However, the overflow port of the bubble cap type distributor is a straight slit, and the macroscopic uniformity of the bubble cap type distributor is not as good as that of the overflow type distributor. And the bubble cap distributor has larger size and larger installation distance, and occupies more space of the reactor. Moreover, due to the large flow in the central region of the bubble cap distributor, the microscopic distribution of the liquid phase is not uniform; and because the flow state of the bubble cap distributor is plug flow, the impact force is larger. For the reasons, the bubble cap distributor has to be filled with an inert ceramic ball layer with enough thickness when in use to reduce the impact force and assist in uniformly dispersing the liquid phase, and the liquid phase can be uniformly dispersed only after flowing through a certain section of bed layer depth, thereby wasting precious reactor space.

The wide range of fractions from crude gasoline to residual oil can be used as the raw material of a hydrogenation device, the flow state working condition of the crude gasoline can be divided into full gas phase and gas liquid phase flow, even if the gas phase and the liquid phase working condition exist, the hydrogen-oil ratio of the crude gasoline is greatly different, and the liquid phase density and the viscosity of the crude gasoline are greatly different, so that the bubble cap distributor based on the suction principle cannot be suitable for all the working conditions.

In addition, along with the fact that the raw oil deterioration is getting worse, the processing process flow is longer and longer, and the degree of continuity is higher and higher, rust scale generated by corrosion of equipment and process pipelines caused by acid in the raw oil, an auxiliary agent carried by instability of an upstream process, dissolved oxygen in the storage and transportation process and the like can generate scale after entering a hydrogenation reactor, and a top distribution disc is covered. The bubble cap distributor based on the suction principle is easily covered or partially covered, so that the material distribution is not uniform, and when the inlet liquid is not uniformly distributed, the effect of the distributor at the top of the hydrogenation reactor can be seriously influenced.

Aiming at the technical problems that the traditional gas-liquid distributor is weaker in tower plate inclination resistance and large in influence of uneven liquid layer depth on a distribution plate, a novel inner member technology with the functions of reducing impact and flow equalization, small in size, good in distribution effect and low in installation precision must be developed for reducing the strong impact force formed by the residual kinetic energy of fluid entering a reactor, eliminating the 'wave pushing' phenomenon of the fluid in an inclined flow state on the liquid layer on the distribution plate and realizing the uniform distribution of the fluid.

Disclosure of Invention

Aiming at the defects in the prior art, the invention provides a sleeve type impact reduction flow equalizing disc. The sheath cylinder type impact reduction and flow equalization disc is arranged in an idle reactor upper end enclosure or arranged at the upper end of a reactor cylinder body and above a top distribution disc. The sleeve type impact reduction flow equalizing disc is a newly added reactor inner component and can be used for reducing the strong impact force formed by the residual kinetic energy when fluid enters the reactor; the 'wave pushing' phenomenon of the inclined flow line formed when the central point enters the distribution tray liquid layer can be eliminated, and the impact force generated by the potential energy conversion of the fluid falling from the inlet of the reactor to the top distribution tray is eliminated; the functions of fine adjustment of fluid flow state and initial distribution of materials are realized, or the distribution function of a top distribution plate is replaced; good access conditions can be provided for the top dispensing tray. Compared with the prior art, the sleeve type impact-reducing flow-equalizing disc has good distribution effect, fully utilizes the idle space of the reactor end socket, and has the characteristics of small volume, simple structure, convenient installation, large operation elasticity and the like.

The technical scheme of the invention is as follows:

a sleeve type impact-reducing flow-equalizing disc comprises a tower tray and a plurality of chimney type distributors arranged on the tower tray; the chimney type distributor comprises a downcomer and a shock-absorbing cylinder arranged at the upper end of the downcomer; the impact reduction cylinder and the downcomer are both of cylindrical structures with openings at two ends, the impact reduction cylinder and the downcomer are arranged up and down, and the diameter of the impact reduction cylinder is larger than that of the downcomer.

Furthermore, the impact reduction cylinder and the downcomer are arranged in an up-and-down, coaxial and annular sleeve manner.

Furthermore, the sectional area of the impact reducing cylinder and the sectional area of the chimney distributor have a corresponding relationship. The bottom edge of the impact-reducing cylinder is fixedly connected with the upper edge of the downcomer in an overlapping or non-overlapping manner, and can also be arranged in an overlapping manner with the upper part of the downcomer. When arranged overlappingly, the proportion of the overlap height to the height of the downcomer is from 5% to 30%, preferably from 10% to 25%.

Further, a gap with a certain distance exists between the impact reduction cylinder and the horizontal direction of the downcomer. The sectional area of the impact reducing cylinder is 1.1-3 times, preferably 1.5-2.5 times of that of the downcomer. The impact reduction cylinder and the downcomer can be fixed and connected through a pull rod (or a pull rib).

In the present invention, the tray generally further comprises support beams and tray connectors for securing the tray.

Furthermore, a plurality of tooth grooves are formed in an opening of the upper edge of the impact reduction barrel.

In the invention, the reactor suitable for the sleeve type impact reduction and flow equalization disc is a fixed bed reactor which is fed upwards and has a gas-liquid parallel flow mode, and is particularly suitable for a fixed bed trickle bed reactor mode. More preferably, the reactor is a hydrogenation reactor containing a large amount of unsaturated hydrocarbons or fouling materials in the feedstock and having a relatively large scale (e.g., a reactor diameter of 4 meters or more). The sleeve type impact reduction and flow equalization disc is suitable to be arranged in an idle reactor upper end socket or arranged at the upper end of a reactor barrel and above a top distribution disc.

Further, the chimney distributors are vertically arranged on the tray. The lower end opening of the downcomer in the chimney distributor is directly opened on the tray or penetrates through the opening of the tray.

Further, the chimney distributor may be made of any suitable material, such as ceramic, metal, etc., and preferably made of steel. The impact reduction cylinder and the downcomer can be integrally manufactured; or, a cylindrical impact-reducing cylinder is fixedly connected to the upper edge of the downcomer. The fixed connection can adopt various suitable modes such as welding, bolt connection, screw connection and the like.

In the sleeve type impact-reducing flow-equalizing disc, the impact-reducing cylinder and the downcomer are both made of metal pipes. The pipe wall of the downcomer is provided with 1-6 overflow holes in the horizontal direction, and the number of the overflow holes is preferably 1-2. The total cross section area of the overflow holes in each chimney type distributor is 10-100%, preferably 30-50% of the cross section area of the downcomer. The shape of the overflow hole can be round, long strip, triangle and polygon, preferably round. The distance between the center line of an overflow hole arranged on the downcomer and the surface of the tray is 5-100 mm, and preferably 30-50 mm; the height of the downcomer is 20-300 mm, preferably 50-120 mm.

In the sleeve type impact reduction and flow equalization disc, a plurality of chimney type distributors with impact reduction and flow equalization functions can be arranged on one layer of sleeve type impact reduction and flow equalization disc. The chimney type distributors with the impact reducing function are arranged on the tower tray in a triangular, quadrangular or rhombic shape.

In the sleeve type impact reduction flow equalizing disc, a tower tray is generally divided into a plurality of blocks and can be spliced into a circular plate. The outermost edge of the tray is provided with a folded edge which is folded upwards; the height of the folded edge of the tower tray is generally 5-80 mm, preferably 30-50 mm.

In the invention, the downcomer is used for liquid to pass through and is also used as a flow channel for gas feeding in feeding.

Compared with the prior art, the sleeve type impact reduction and flow equalization disc has the following advantages:

1. the sleeve type flow-equalizing disc reduces the installation size of the distributor through special structural design, is convenient to be installed at an idle upper end socket of a reactor or arranged at the upper end of a reactor cylinder body and above a distribution disc at the top, achieves the aim of saving the space of the reactor, improves the space utilization rate of a hydrogenation reactor, is convenient to load more catalysts or reduces the scale of the reactor.

2. The sleeve type flow equalizing disc is provided with a distributor with a shock reducing function, and a shock reducing cylinder at the upper part of the distributor blocks jet fluid in an inclined flow state to reduce the impact force of the jet fluid; the fluid losing kinetic energy is blocked and then converted into a vertical flow state from the original inclined line flow state under the action of gravity, natural falling is realized, a liquid layer with consistent depth is formed on the tray, the phenomenon of 'pushing waves' formed by the liquid layer on the tray by the impact force of the inclined line is eliminated, uniform inlet conditions are created for the chimney distributor, the material is distributed on the top part distribution plate through the chimney distributor, the primary distribution function is realized, and friendly, stable liquid layer and uniform inlet conditions are provided for the distributor. The chimney distributor with the flow equalizing function is suitable in quantity, and can replace the existing top distribution plate to achieve uniform distribution of materials. The sleeve type impact reduction and flow equalization plate improves the inlet working condition of the first bed layer distribution plate, improves the distribution effect of the distribution plate, optimizes the material distribution of the top bed layer and improves the utilization rate of the first bed layer catalyst.

3. According to the sleeve type flow equalizing disc, the tooth grooves are formed in the upper edge of the impact reducing cylinder, liquid sprayed in an inclined line impacts the tooth grooves to form a large splashing area, a dispersion phase is formed, impact force can be reduced, a dispersion area in a large area can be formed, and a uniform liquid layer can be formed on the tray.

4. Compared with a bubble cap distributor adopting a general suction principle, the sleeve type flow equalizing disc realizes liquid phase distribution by the aid of the impact reducing cylinder and the chimney type distributor, and compared with a bubble cap distributor adopting the general suction principle, the dispersed power of liquid phase distribution is changed from gas phase suction into potential energy to form splashing, so that pressure drop is reduced.

5. According to the sleeve type flow equalizing disc, the positions and the shapes of the overflow holes in the pipe wall of the chimney distributor are arranged, so that reasonable liquid storage depth of the tray is formed, and macroscopic distribution unevenness caused by levelness deviation and liquid level fluctuation of the tray is reduced.

6. The sleeve type flow equalizing disc adopts a unique design principle and the characteristics of hydrodynamics to realize the uniform distribution of materials, so that the radial temperature difference of a catalyst bed layer is reduced, the radial temperature difference of the catalyst bed layer is less than or equal to 3 ℃, and the radial temperature difference reflects the distribution effect of fluid, thereby fully showing that the grid type flow equalizing disc has better distribution effect on reaction feed material flow and gas-liquid mixing effect and has certain auxiliary effect on the hydrogenation catalytic reaction process and the control of catalyst coking.

7. Compared with the prior art, the sleeve type impact-reducing flow-equalizing disc has the advantages of simple structure, convenience in installation and high operation elasticity, can improve the space utilization rate of a hydrogenation reactor, improve the inlet condition of top-divided materials of the reactor, improve the radial distribution effect of the fed materials of the reactor, effectively eliminate the radial temperature difference of the reactor, eliminate the hot spot of a catalyst bed layer caused by uneven material distribution, provide excellent inlet conditions for the effective use of a catalyst in the hydrogenation reactor, reduce the times of catalyst skimming or agent changing, prolong the start-up period of the device, improve the hydrogenation process effect and have good economic benefit.

Drawings

FIG. 1 is a schematic view of a sleeve type flow equalizing plate structure.

Wherein, 1 is a chimney distributor, 2 is a tray, 3 is a tray connecting piece, 4 is a tray supporting beam, and 5 is an overflow hole.

FIG. 2 is a schematic diagram of the structure of a chimney distributor. Wherein, 1-1 is a shock reducing cylinder, 1-2 is a downcomer, and 1-3 is a pull rod.

FIG. 3 is a top view of the structure of the chimney distributor.

FIG. 4 is a schematic view of the fluid flow pattern of the sleeve-type flow-reducing and flow-equalizing tray of the present invention.

FIG. 5 is a schematic view of the positions of different temperature measuring points on the same bed section in the embodiment of the invention.

Detailed Description

As shown in fig. 1-3, the sleeve-type flow-reducing and equalizing tray of the present invention comprises a tray 2 and a plurality of chimney distributors 1 vertically arranged on the tray. The chimney type distributor comprises a downcomer 1-2 and a shock-absorbing cylinder 1-1 arranged at the upper end of the downcomer, and the downcomer and the shock-absorbing cylinder are fixedly connected through a pull rod 1-3. The impact reduction cylinder and the downcomer are both of a cylindrical structure with two open ends, the impact reduction cylinder and the downcomer are arranged up and down, and the diameter of the impact reduction cylinder is larger than that of the downcomer.

Wherein, the impact reducing cylinder has a certain specification. The height of the impact reducing cylinder is generally 30-400 mm, and preferably 100-300 mm; the diameter of the impact reducing cylinder is generally 30-260 mm, preferably 80-150 mm. The upper edge opening of the impact reduction barrel is preferably also provided with a tooth groove, and the tooth groove is triangular, rectangular or circular arc-shaped, preferably triangular. The height of the tooth socket is 1-20%, preferably 2-10% of the height of the impact reducing cylinder.

As shown in FIGS. 2-3, in the sleeve-type impact-reducing flow-equalizing tray of the present invention, a gap exists between the impact-reducing cylinder and the downcomer in the horizontal direction to serve as a gas phase channel, and the gap width is generally 5 to 200mm, preferably 10 to 50 mm. The impact reduction cylinder and the downcomer are preferably arranged in an up-and-down, coaxial and annular sleeve manner. The sectional area of the impact reducing cylinder is 1-8 times, preferably 2-6 times of that of the downcomer. The bottom edge of the impact reduction cylinder is connected with the upper edge of the downcomer and can also be arranged in an overlapping way with the downcomer. When the bottom edge of the impact-reducing plate is overlapped with the downcomer part, the overlapping height is generally 5 to 30 percent of the height of the downcomer, and preferably 10 to 25 percent.

In the sleeve type impact-reducing flow-equalizing disc, the impact-reducing cylinder and the downcomer are generally made of metal pipes. The height of the downcomer is generally 20 to 300mm, preferably 50 to 120 mm. On the pipe wall of downcomer, be the horizontal direction and set up 1 ~ 6 overflow holes usually, preferably 1 ~ 2. The total cross-sectional area of the overflow apertures is typically 10% to 100%, preferably 30% to 50% of the cross-sectional area of the downcomer. The shape of the overflow hole can be round, long strip, triangle and polygon, preferably round. The central line of the overflow hole arranged on the downcomer is 5-100 mm, preferably 30-50 mm, away from the upper surface of the tray.

In the sleeve type impact reduction and flow equalization disc, a plurality of chimney type distributors with impact reduction and flow equalization functions can be arranged on one layer of sleeve type impact reduction and flow equalization disc. The chimney type distributors with the impact reducing function are arranged on the tower tray in a triangular, quadrangular or rhombic shape. The chimney distributor is usually inserted on the tray (plate) through the lower end of the downcomer and can be fixedly connected by welding, screwing, fastening and the like.

In the sleeve type impact reduction flow equalizing disc, a tower tray is generally divided into a plurality of blocks and can be spliced into a circular plate. The edge of the outermost edge of the tray is provided with a folded edge which is folded upwards, and the height of the folded edge is generally 5-80 mm, preferably 30-50 mm.

With reference to fig. 1-4, the working method and process of the sleeve type impact reduction and flow equalization disc of the invention are as follows:

when the device works, fluid which has larger impact force and enters from the center of the reactor is sprayed to the periphery in an inclined line manner, the fluid impacts the impact reduction barrel to effectively block the fluid sprayed in an inclined line flow state, the impact force of the fluid is reduced and adjusted, the fluid is blocked and naturally falls under the action of gravity after losing kinetic energy to form a vertical falling flow state, and liquid phase potential energy is converted into kinetic energy of a free falling body and falls onto a tower plate of the impact reduction flow-equalizing disc. According to the sleeve type flow equalizing disc, the tooth grooves are formed in the upper edge of the impact reducing cylinder, liquid sprayed in an inclined line impacts the tooth grooves to form a large splashing area, a dispersion phase is formed, impact force can be reduced, a dispersion area in a large area can be formed, and a uniform liquid layer can be formed on the tray. Because distributor material passageway is horizontal arrangement and has certain difference in height apart from the tray plate, therefore the material can form the liquid layer on the tray plate that subtracts towards the flow equalizing dish, therefore the material can reduce to dash the liquid layer that the certain degree of depth was formed on the tray plate upper surface of flow equalizing dish at the grid formula, even there is the deviation in the tray levelness, still can ensure that every distributor all has the liquid phase to exist. Because the number of the distributors is large, any point on the surface of the catalyst bed layer is provided with a certain number of distributors for working, so that the uniformity of the distributors is guaranteed. The materials flow into the distribution pipe from an overflow hole channel arranged on the pipe wall of the chimney type distributor, so that the primary distribution of the liquid is realized. Because the materials after passing through the flow reducing and equalizing disc are converted into a vertical flow state when being distributed on the top distribution disc, and the kinetic energy disappears, the liquid layer on the surface of the tray plate of the top distribution disc has no thrust any more, the phenomenon of 'pushing waves' of the materials on the liquid layer on the distribution disc is eliminated, friendly, stable liquid layer and uniform inlet conditions are provided for the top distributor, and the materials are uniformly distributed on the catalyst bed layer together with the top distribution disc.

When the liquid material quantity in the hydrogenation reactor is less, or the upper part of the catalyst bed layer is filled with a tooth-ball-shaped protective agent or a hollow ball-shaped protective agent, the sleeve type impact reduction and flow equalization disc can even replace a top distribution disc to realize the integration of impact reduction, flow equalization and distribution, thereby greatly simplifying the internal structure of the reactor and reducing the investment.

The following examples are given to illustrate the reaction effect of the present invention, but do not limit the scope of the present invention.

Comparative example 1

Hydrofining of gasoline in a refineryThe diameter of the reactor is 3.0m, the reactor is idle in an upper end enclosure, a top distribution disc is arranged at the entrance of a catalyst bed layer at the uppermost layer, an ERI type bubble cap type gas-liquid distributor which is conventional in the field is used in the top distribution disc, a hydrogenation raw material is gasoline fraction, a catalyst is an FGH-21 type hydrofining catalyst produced by the comforting petrochemical research institute, and the process conditions of the reactor are as follows: the operating pressure is 1.85MPa, and the volume space velocity is 2.5h^-1The hydrogen-oil volume ratio was 355:1, the reactor inlet temperature was 285 ℃, and the catalyst bed radial temperature and temperature differential are shown in table 1.

Example 1

After transformation, the sleeve type impact reduction flow equalizing disc is added in the upper end enclosure, and the sleeve type impact reduction flow equalizing disc shown in figure 1 is combined with a common ERI type bubble cap type gas-liquid distributor for use. The main parameters of the sleeve type flow equalizing disc are as follows: the height of the impact reducing cylinder is preferably 300 mm; the diameter of the impact reducing cylinder is preferably 150 mm; the upper edge of the impact reducing cylinder is provided with a triangular tooth socket, and the height of the tooth socket is 10% of the height of the impact reducing cylinder. The gap between the flushing reducing cylinder and the chimney distributor in the horizontal direction is preferably 30 mm; the sectional area of the impact reducing cylinder is 5 times of that of the chimney distributor; the bottom edge of the impact reduction barrel is overlapped with the chimney distributor; the overlap position is 20% of the chimney distributor height; the height of the chimney distributor is 120 mm; 2 overflow ports are arranged on the pipe wall of the chimney distributor in the horizontal direction. The total cross-sectional area of the overflow holes is 30% of the cross-sectional area of the chimney distributor pipe; the pipe wall of the chimney distributor is provided with an overflow hole which is round; the center line of an overflow hole arranged on the pipe wall of the chimney distributor is 50mm away from the upper surface of the tray. In the sleeve type impact-reducing flow-equalizing disc, the chimney type distributor is arranged on the tower disc in a triangular mode. The tray can be divided into 9 blocks and can be spliced into round plates, each cutting plate is provided with 3 chimney type distributors, and the edge of the outermost edge of the tray is provided with a folding edge, wherein the height of the folding edge is generally 50 mm.

The hydrogenation feedstock and process conditions were the same as in comparative example 1.

The inlet radial temperature and maximum temperature differential of the first catalyst bed after restart are shown in table 1.

Example 2

After transformation, the sleeve type impact reduction flow-equalizing disc is added in the upper end socket, and an ERI type gas-liquid distributor in the prior art in the original reactor is eliminated, wherein the sleeve type impact reduction flow-equalizing disc has the main parameters: the height of the impact reducing cylinder is preferably 300 mm; the diameter of the impact reducing cylinder is preferably 150 mm; the upper edge of the impact reducing cylinder is provided with a triangular tooth socket, and the height of the tooth socket is 10% of the height of the impact reducing cylinder. The gap between the flushing reducing cylinder and the chimney distributor in the horizontal direction is preferably 30 mm; the sectional area of the impact reducing cylinder is 5 times of that of the chimney distributor; the bottom edge of the impact reduction barrel is overlapped with the chimney distributor; the overlap position is 20% of the chimney distributor height; the height of the chimney distributor is 120 mm; 2 overflow ports are arranged on the pipe wall of the chimney distributor in the horizontal direction. The total cross-sectional area of the overflow holes is 30% of the cross-sectional area of the chimney distributor pipe; the pipe wall of the chimney distributor is provided with an overflow hole which is round; the center line of an overflow hole arranged on the pipe wall of the chimney distributor is 50mm away from the upper surface of the tray. In the sleeve type impact-reducing flow-equalizing disc, the chimney type distributor is arranged on the tower disc in a triangular mode. The tray can be divided into 9 blocks and can be spliced into round plates, each cutting plate is provided with 3 chimney type distributors, and the edge of the outermost edge of the tray is provided with a folding edge, wherein the height of the folding edge is generally 50 mm.

The radial temperature distribution and the maximum temperature difference at the inlet of the first bed layer after the restart are shown in the table 1.

TABLE 1 results of application

	Comparative example 1	Example 1	Example 2
				Temperature a, C	285.3	285.8	286.0
Temperature b, C	289.6	286.3	286.2
				Temperature c, C DEG C	278.6	286.7	286.1
Temperature d, DEG C	278.3	285.5	284.6
				Temperature e,. degree.C	284.3	285.4	285.6
Maximum radial bed temperature difference, deg.C	11.3	1.3	1.6

Claims

1. A sleeve type impact reduction and flow equalization plate is arranged in an idle upper end socket of a reactor or arranged at the upper end of a cylinder body of the reactor and above a top distribution plate, and comprises a tower tray and a plurality of chimney type distributors arranged on the tower tray; the chimney type distributor comprises a downcomer and a shock-absorbing cylinder arranged at the upper end of the downcomer; the impact reduction barrel and the downcomer are both of a cylindrical structure with openings at two ends, the impact reduction barrel and the downcomer are arranged in an up-down annular sleeve mode, and the diameter of the impact reduction barrel is larger than that of the downcomer.

2. The telescopic, surge-reducing, flow-equalizing tray of claim 1, wherein said surge-reducing barrels are arranged coaxially with the downcomer.

3. The telescopic impact-reducing flow-equalizing tray according to claim 1, wherein the bottom edge of the impact-reducing cylinder is fixedly connected with the upper edge of the downcomer in an overlapping or non-overlapping manner.

4. The telescopic, surge-reducing, flow-equalizing tray of claim 1, wherein a gap exists between said surge-reducing barrel and the downcomer in a horizontal direction.

5. The telescopic impact-reducing flow-equalizing tray according to claim 1, wherein the impact-reducing cylinder and the downcomer are fixed and connected by tie rods or tie bars.

6. The telescope-feed erosion reduction and flow equalization plate of claim 1, wherein said tray further comprises support beams and tray connectors for securing the tray.

7. The telescopic shock-reducing flow-equalizing disc of claim 1, wherein said shock-reducing cylinder has a plurality of splines formed on its upper edge.

8. The telescopic impact reducing flow equalizing disc of claim 7, wherein said gullets are triangular, rectangular or circular arc shaped.

9. The spool-type flow-reducing flow-equalizing tray according to claim 1, wherein said reactor is a fixed bed reactor with an upper feed and a co-current flow of gas and liquid.

10. The telescope-feed erosion reduction and flow equalization plate of claim 1, wherein the lower end opening of said downcomer opens directly into or through the tray opening.

11. The telescopic shock-reducing flow-equalizing tray of claim 1, wherein said shock-reducing cylinder and said downcomer are integrally formed; or, a cylindrical impact-reducing cylinder is fixedly connected to the upper edge of the downcomer.

12. The telescopic flow reducing and equalizing disc of claim 11, wherein said fixed connection is by welding, bolting, or screwing.

13. The telescopic impact-reducing flow-equalizing disc of claim 1, wherein 1-6 overflow holes are horizontally arranged on the wall of the downcomer, and the total cross-sectional area of the overflow holes is 10-100% of the cross-sectional area of the downcomer.

14. The telescope-feed impact-reducing flow-equalizing disc according to claim 13, wherein the number of overflow apertures is 1 to 2, and the total cross-sectional area of the overflow apertures is 30 to 50% of the cross-sectional area of the downcomer.

15. The spool-type flow-reducing and flow-equalizing disc of claim 13, wherein said overflow apertures are circular, quadrilateral or triangular in shape.

16. The telescope-type flow-reducing and flow-equalizing tray according to claim 1, wherein said chimney distributors are arranged in a triangular or quadrangular pattern on the tray.

17. The telescope-type flow reducing and equalizing disc of claim 1, wherein said tray is divided into a plurality of pieces and is spliced into a circular plate.

18. The telescope-feed shock-reducing flow-equalizing disc according to claim 1, wherein the outermost peripheral edge of said tray is provided with an upturned flange.

19. The telescope-feed flow-reducing and flow-equalizing disc according to claim 13, wherein the centerlines of said spill orifices are 5 to 100mm from the surface of the tray.

20. The telescopic impact-reducing flow-equalizing tray of claim 1, wherein the height of said downcomer is 20 to 300 mm; the height of the impact reducing cylinder is 30-400 mm; the diameter of the impact reducing cylinder is 30-260 mm.

21. A sleeve-type impact-reducing flow-equalizing disc according to claim 18, wherein said flange has a height of 5 to 80 mm.

22. A telescopic, surge-reducing flow-equalizing disc according to claim 7 or 8, wherein the height of said gullets is between 1% and 20% of the height of the surge drum.

23. A sleeve-type flow-reducing and flow-equalizing disc according to claim 4, wherein said gap has a width of 5 to 200 mm.

24. The telescopic impact-reducing flow-equalizing tray according to claim 1, wherein the cross-sectional area of the impact-reducing cylinder is 1 to 8 times the cross-sectional area of the downcomer.

25. A telescopic impact-reducing flow-equalizing tray according to claim 3, wherein the bottom edge of said impact-reducing cylinder overlaps the downcomer section by a height of 5% to 30% of the height of the downcomer.