CN212651792U - Gas-liquid mixing equipment - Google Patents

Abstract

The invention discloses a gas-liquid mixing device. The gas-liquid mixing equipment comprises a catalyst grid, a cold hydrogen distributor, a gas-liquid distributor, a distribution disc, a flow crushing plate and a shell. The cold hydrogen distributor mainly comprises a cold hydrogen distribution pipe and straight nozzles, wherein the cold hydrogen distribution pipe comprises a distribution ring pipe and distribution straight pipes, the distribution ring pipe and the distribution straight pipes are both positioned in the same plane, the distribution ring pipes are arranged in a concentric circle shape, the distribution straight pipes are communicated with the distribution ring pipes in a crossing manner, the distribution pipe is provided with the straight nozzles which are arranged in pairs and are inclined upwards at intervals along the axis of the distribution pipe, one end of one distribution straight pipe is a cold hydrogen inlet, and each straight nozzle is a cold hydrogen outlet; the invention has simple and compact structure, and is suitable for being used between catalyst beds of a large-diameter downflow reactor; the cold hydrogen can be distributed more uniformly on the whole cross section of the reactor, and can be fully mixed with reaction oil gas, thereby ensuring the uniform proceeding of mass transfer and heat transfer and improving the heat transfer efficiency of the medium in the reactor.

Description

Gas-liquid mixing equipment

Technical Field

The utility model belongs to the petroleum processing field relates to a gas-liquid mixture distributor for hydrogenation ware, and specifically speaking relates to a gas-liquid mixing equipment.

Background

In the hydrogenation process, because of the exothermic reaction of three phases of gas, liquid and solid, in order to make the reaction feed (gas phase and liquid phase) and the catalyst (solid phase) fully, uniformly and effectively contact, a hydrogenation reactor is generally designed with a plurality of catalyst beds, a distribution disc is arranged at the top of each bed, and a temperature control structure (cold hydrogen box) is arranged between the two beds so as to ensure the safe and stable production of a hydrogenation device and prolong the service life of the catalyst.

The hydrogenation reaction of hydrocarbons belongs to exothermic reaction, for the hydrogenation reactor with multiple beds, the temperature of oil gas and hydrogen will rise after the reaction in the previous bed, and cold hydrogen must be introduced between the two beds to control the temperature for the next bed to continue effective reaction. The tubes that introduce and distribute the cold hydrogen gas inside the reactor are called cold hydrogen tubes. The role and requirements of the cold hydrogen addition system are: uniformly and stably supplying enough cold hydrogen; the cold hydrogen must be thoroughly mixed with the hot reactants and have a uniform temperature and material distribution on entering the next bed. The cold hydrogen pipe is divided into a direct insertion type, a dendritic type and a ring structure according to the form.

The cold hydrogen tank is a combination of a mixing tank and a pre-distribution plate. It is the place where the hot reactant and cold hydrogen in the hydrogenation reactor are mixed and heat exchanged. The reaction product flowing down from the upper layer and the cold hydrogen injected from the cold hydrogen pipe are fully mixed in the box to absorb the reaction heat, reduce the temperature of the reactant, meet the reaction requirement of the next catalyst bed layer and avoid the over-temperature of the reactor.

The first layer of the cold hydrogen box is a baffle plate disk, and the baffle plate is provided with a throttling hole. The cold hydrogen from the cold hydrogen pipe and the oil gas after the reaction of the previous bed layer are premixed on the baffle disc and then enter the cold hydrogen box through the throttling hole. Cold hydrogen entering the cold hydrogen box and hot oil gas from the upper layer are repeatedly baffled and mixed, then flow to the second layer of the cold hydrogen box, namely the sieve plate disc, and are baffled again on the sieve plate disc to strengthen the mixing effect, and then are distributed. And a layer of redistributing tray is arranged below the sieve tray to redistribute the oil gas after the predistribution.

The redistributing tray consists of a tray plate and distributors uniformly distributed on the tray plate. The redistribution plate is arranged on the catalyst bed layer, and aims to uniformly distribute the reaction medium, improve the flow condition of the reaction medium, realize good contact with the catalyst and further achieve uniform distribution in the radial direction and the axial direction. The types of distributors are more, and the hydrogenation reactors designed and manufactured by China mostly adopt bubble cap type distributors.

Patent CN201610010133.6 provides a rotational flow cold hydrogen pipe of a hydrogenation reactor, which comprises a feeding pipe connected with an outlet of a cold hydrogen storage tank, a distribution ring pipe connected to the feeding pipe, and a plurality of nozzles mounted on the distribution ring pipe, wherein the nozzles are uniformly arranged around the outer wall of the ring of the distribution ring pipe; the nozzle is of a cylinder shape, a notch is formed at the tail end of the side wall of the nozzle, an end cover is arranged at the tail end of the nozzle, and the notches of the plurality of nozzles are in the same or opposite directions.

Patent CN201620014039.3 discloses a mixing system comprising: the catalyst comprises a shell, an upper catalyst layer, a lower catalyst layer and a hydrogenation pipe; the upper catalyst layer and the lower catalyst layer are arranged in the shell at intervals from top to bottom, and a mixing cavity is formed between the upper catalyst layer and the lower catalyst layer; one end of the hydrogenation pipe is arranged in the mixing cavity; the side wall of the hydrogenation pipe is provided with a plurality of air outlets. Cold hydrogen flows into the mixing cavity from the plurality of air outlets, the reaction fluid can be fully mixed with the cold hydrogen when flowing into the mixing cavity, and the reaction fluid and the cold hydrogen can be fully mixed when the hydrogenation pipe is introduced with the cold hydrogen, so that the space of the mixing cavity is reduced, but the heat transfer and mass transfer are not uniform enough, and the reaction is not stable enough.

At present, with the upsizing of a hydrogenation device and the development of a new hydrogenation technology, the diameter of a hydrogenation reactor is larger and larger, and the catalyst bed layer of a single hydrogenation reactor is increased. After the hydrogenation reactor is enlarged, the advanced applicability of the inner member becomes more important, and how to realize the uniform distribution of the gas-liquid two-phase fluid in the bed layer, ensure the uniform proceeding of mass transfer and heat transfer and improve the heat transfer efficiency of the medium in the reactor becomes more difficult and more important. For example, the foreign advanced gas-liquid distributor is combined with the advanced catalyst filling technology to ensure that the temperature on the inner section of the reactor is very uniform, and the temperature difference reaches the level of less than or equal to 1 ℃, thereby being beneficial to the operation control of the reactor and greatly prolonging the service life of the catalyst.

Disclosure of Invention

In order to solve the technical problems that the gas-liquid two-phase fluid in the prior art is difficult to be distributed uniformly in a catalyst bed layer, the mass and heat transfer is not uniform enough and the heat transfer efficiency is low, the utility model provides a gas-liquid mixing device.

The equipment comprises a catalyst grid, a cold hydrogen distributor, a gas-liquid distributor, a distribution disc and a shell; the catalyst grating, the cold hydrogen distributor, the gas-liquid distributor and the distribution disc are all arranged in the shell; the cold hydrogen distributor is arranged below the catalyst grating, the gas-liquid distributor is vertically fixed on the distribution disc and arranged below the cold hydrogen distributor, and the catalyst grating and the distribution disc are fixed on the inner wall of the shell.

As an improved scheme, a flow crushing plate is arranged below the gas-liquid distributor close to the wall of the reactor and two sides of a support beam of the distribution plate, the flow crushing plate can be a flat plate or a conical plate, support ribs are arranged on the flow crushing plate, two ends of each support rib are respectively connected with the gas-liquid distributor and the flow crushing plate, and a plurality of small holes are formed in the flow crushing plate.

The cold hydrogen distributor mainly comprises a cold hydrogen distribution pipe and straight nozzles, wherein the cold hydrogen distribution pipe comprises a distribution ring pipe and distribution straight pipes, the distribution ring pipe and the distribution straight pipes are positioned in the same plane, the distribution ring pipes are arranged in a concentric circle shape, the distribution straight pipes are communicated with the distribution ring pipes in a crossing manner, the distribution pipe is provided with obliquely upward straight nozzles which are arranged in pairs at intervals along the axis of the distribution pipe, one end of one distribution straight pipe is a cold hydrogen inlet, and each straight nozzle is a cold hydrogen outlet; the two straight nozzles arranged in pairs are arranged in an axial symmetry mode, and each straight nozzle and the horizontal plane form an angle of 30-60 degrees.

As the improved scheme, the end part of each straight nozzle is provided with a contraction hole, the end part close to the straight nozzle is uniformly provided with jet holes along the circumferential direction, and the number of the jet holes is 2-8 so as to ensure the uniform distribution of cold hydrogen.

The utility model provides a gas-liquid mixing device's theory of operation does:

the reaction oil gas of the upper catalyst bed layer flows downwards through the catalyst grating, and cold hydrogen is introduced between the two bed layers to control the temperature for the next bed layer to continue effective reaction. Cold hydrogen is introduced into the bed layer through the cold hydrogen distributor, reaction oil gas and cold hydrogen from the upper layer are uniformly mixed and continue downwards, the reaction oil gas and the cold hydrogen are further mixed and distributed through the gas-liquid distributor and the flow crushing plate, more part of oil gas is diffused along the periphery to the radial direction, so that the radial direction distribution is more uniform, the phenomenon that the oil gas is not uniform under the inner wall and the supporting beam is avoided, dead zones are reduced, and the next bed layer reaction is more effective.

The utility model discloses following beneficial effect has:

1) the unique structure of the cold hydrogen distributor ensures that the cold hydrogen is more uniformly distributed on the whole cross section of the reactor and can be fully mixed with reaction oil gas, thereby ensuring the uniform proceeding of mass transfer and heat transfer and improving the heat transfer efficiency of the medium in the reactor;

2) the cold hydrogen distributor consists of a distribution pipe and a straight nozzle, has simple and compact structure, can greatly save the investment of the reactor, is more convenient to install and disassemble, and is suitable for being used between catalyst beds of a large-diameter downflow reactor.

3) The setting of garrulous flow board, the miscella continuance is carried out the redistribution downwards through garrulous flow board, and more most oil gas is along all around to radial direction diffusion for radial direction distribution is more even, has avoided the inhomogeneous phenomenon of inner wall department and supporting beam lower oil gas, makes the reaction oil gas more even that distributes between the catalyst bed, and the reaction is more stable, changes in the operation of control reactor.

Drawings

Fig. 1 is a schematic structural diagram of a cold hydrogen distributor according to the present invention;

FIG. 2 is a schematic view of the structure in the direction A-A of FIG. 1;

FIG. 3 is a schematic structural view of the straight nozzle of FIG. 2;

FIG. 4 is a schematic structural view of the gas-liquid mixing apparatus of the present invention;

FIG. 5 is a schematic view of the structure of a breaker plate;

FIG. 6 is a top view of FIG. 5;

in the figure: 1-distribution ring pipe, 2-distribution straight pipe, 3-straight nozzle, 4-cold hydrogen distribution pipe, 5-shrinkage hole, 6-jet hole, 7-cold hydrogen inlet, 8-shell, 9-catalyst grid, 10-catalyst grid supporting beam, 11-cold hydrogen distributor supporting beam, 12-cold hydrogen distributor, 13-gas-liquid distributor, 14-distribution plate, 15-distribution plate supporting beam, 16-flow crushing plate, 17-catalyst bed layer and 18-support rib.

Detailed Description

The present invention will be further described with reference to the accompanying drawings.

As shown in figures 1-3, the utility model discloses cold hydrogen distributor among gas-liquid mixing equipment is including distribution ring canal 1, distribution straight tube 2 and straight nozzle 3, and cold hydrogen distribution pipe 4 in figure 2 is including both distributing ring canal 1 and distributing straight tube 2. The distribution ring pipe 1 and the distribution straight pipes 2 are both positioned in the same plane, the distribution ring pipe 1 is arranged in a concentric circle shape, the distribution straight pipes 2 are communicated with the distribution ring pipe 1 in a crossed manner, oblique upward straight nozzles 3 which are arranged in pairs are arranged on the cold hydrogen distribution pipe at intervals along the axis of the distribution pipe, one end of one distribution straight pipe 2 is a cold hydrogen inlet 7, and the straight nozzles 3 are cold hydrogen outlets; two straight nozzles arranged in pair in fig. 2 are arranged in axial symmetry, and each straight nozzle forms an angle of 30-60 degrees with the horizontal plane. The tip of straight nozzle is equipped with shrinkage cavity 5 in fig. 3, is close to straight nozzle tip and evenly is equipped with jet orifice 6 along circumference, and the quantity of jet orifice 6 is 2 ~ 8 to guarantee the evenly distributed of cold hydrogen.

As shown in fig. 4, the gas-liquid mixing apparatus of the present invention includes a housing 8, a catalyst grid 9 fixed on the inner wall of the housing 8 and a catalyst grid support beam 10, a cold hydrogen distributor 12 fixed below the catalyst grid 9 through a cold hydrogen distributor support beam 11, a gas-liquid distributor 13 located below the cold hydrogen distributor 12 and fixed on a distribution plate 14, and a flow breaking plate 16 located below the gas-liquid distributor 13 and connected below the gas-liquid distributor through a support rib 18, wherein the flow breaking plate 16 is provided with a plurality of small holes, the lower part of the flow breaking plate 16 is a catalyst bed 17, and the distribution plate 14 is fixed on the inner wall of the housing 8.

The working principle of the present invention is described below with reference to the accompanying drawings:

the reaction oil gas of the upper catalyst bed layer flows downwards through the catalyst grid 9, and cold hydrogen is introduced between the two bed layers to control the temperature for the requirement of the next bed layer on continuous effective reaction. Cold hydrogen enters a cold hydrogen distributor 12 through a cold hydrogen inlet 7, is sprayed out from a contraction hole 6 and a spray hole 5 of a straight nozzle 3 arranged on a distribution ring pipe 1 and a distribution straight pipe 2, enters a bed layer space, is uniformly distributed in the radial and circumferential directions of the whole cross section of the reactor, is uniformly mixed with reaction oil gas from the upper layer, and continues to flow downwards. After further mixing and distribution of the distribution disc 14 and the gas-liquid distributor 13 arranged below the cold hydrogen distributor 12, the mixture enters the flow crushing plate 16 below the cold hydrogen distributor for secondary distribution, and more part of oil gas is diffused along the periphery in the radial direction, so that the distribution in the radial direction is more uniform, the phenomenon that the oil gas is not uniform at the inner wall and under the supporting beam is avoided, the dead zone is reduced, and the reaction of the next catalyst bed layer 17 is more effective.

Claims (6)

1. A gas-liquid mixing apparatus characterized by: the equipment comprises a catalyst grating, a cold hydrogen distributor, a gas-liquid distributor, a distribution disc and a shell, wherein the catalyst grating, the cold hydrogen distributor, the gas-liquid distributor and a flow crushing plate are all arranged in the shell from top to bottom; the cold hydrogen distributor is arranged below the catalyst grating, the gas-liquid distributor is vertically fixed on the distribution plate and arranged below the cold hydrogen distributor, flow crushing plates are arranged below the gas-liquid distributor around the wall of the reactor and below the gas-liquid distributors on two sides of a supporting beam of the distribution plate, the flow crushing plates are connected below the gas-liquid distributor through supporting ribs, and the catalyst grating and the distribution plate are fixed on the inner wall of the shell; the cold hydrogen distributor comprises cold hydrogen distributing pipe and straight nozzle, and cold hydrogen distributing pipe is including distribution ring canal and distribution straight tube, and distribution ring canal and distribution straight tube all lie in the coplanar, and the distribution ring canal is concentric circles form and arranges, and distribution straight tube alternately link up with distribution ring canal, is equipped with the ascending straight nozzle in the slant that sets up in pairs along the distribution pipe axis interval on the distribution pipe, and one of them one end that distributes the straight tube is cold hydrogen import, and each straight nozzle is cold hydrogen export.

2. The gas-liquid mixing apparatus according to claim 1, characterized in that: the two straight nozzles arranged in pairs are arranged in an axial symmetry mode, and each straight nozzle and the horizontal plane form an angle of 30-60 degrees.

3. The gas-liquid mixing apparatus according to claim 1, characterized in that: the end part of the straight nozzle is provided with a contraction hole, and spray holes are uniformly arranged close to the end part of the straight nozzle along the circumferential direction.

4. The gas-liquid mixing apparatus according to claim 2, characterized in that: the end part of the straight nozzle is provided with a contraction hole, and spray holes are uniformly arranged close to the end part of the straight nozzle along the circumferential direction.

5. The gas-liquid mixing apparatus according to claim 3 or 4, characterized in that: the number of the jet holes is 2-8.

6. The gas-liquid mixing apparatus according to claim 1, characterized in that: the flow crushing plate is provided with a plurality of small holes.

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