JP7297056B2 - Bubble shell and tube device - Google Patents

Description

The present invention relates to production equipment for gas-liquid processes, which can be used in chemical, petrochemical and other industries.

In most gas-liquid processes, one or more of the initial reagents is in the gas phase, and as reactions occur, the reagents are transformed into a liquid phase or two-phase region, which has high mass transfer rates. is necessary. Furthermore, processes carried out in the liquid and gas phases often involve high heat generation or heat absorption, which require efficient heat exchange between the mixture and the heat transfer agent.

Also of great importance is that local increases or decreases in the temperature of the reaction mixture, or in the concentrations of reagents, can reduce the selectivity and conversion of the process, and the reaction rate, thus promoting heat and mass transfer throughout the device. state uniformity. Uniformity of reaction conditions can be achieved with an instrument that has a uniform volumetric distribution of tubes, ie, a distribution of tubes that uniforms the velocity of the liquid phase flow throughout the device and eliminates stagnation zones.

A conventional shell-and-tube apparatus for performing an exothermic gas-liquid process (reaction) is disclosed in Patent Document 1 (published December 8, 1998). This device has a hollow draft tube inside. The tube contains an impeller means and liquid is recirculated down the tube into the bottom mixing chamber. A liquid stream is introduced into the device through a supply line and a gas is introduced through the line above the level of the liquid. The device uses forced circulation produced by impeller means and thus exhibits improved heat transfer, high productivity and selectivity. However, mounting a high speed rotating structure at a single support point (only in the upper position) is technically problematic because during rotation the impeller can be displaced from the axis of rotation due to tangential forces. Therefore, special seals are required to operate the impeller shaft at high pressure. Furthermore, creating a downward flow of gas-liquid through the central tube requires a high liquid velocity, which causes additional energy loss in the rotation of the impeller. Even with high impeller rotation speeds, the length of the device is severely limited.

US Patent Application Publication No. 2005/0020005 Aug. 9, 1995 discloses an apparatus for conducting gas-liquid chemical and heat and mass transfer processes with high thermal efficiency. By providing multiple paths through the working area, the device can reduce variability in the residence time of liquid reagents within the device (ie, deviation from the rated residence time of the actual flow). The device comprises a bundle of bubble tubes through which the gas-liquid mixture flows upwards from the bottom and circulation tubes through which the liquid returns (circulates) to the bottom of the device. is secured to the tubesheet and housed in a cylindrical vertical housing, the apparatus also comprises an upper chamber with a vertical plate and a lower chamber with a gas distribution device. The housing has heat transfer agent supply and recovery nozzles and the lower chamber has gas supply and exhaust nozzles. This apparatus is characterized by providing a vertical partition in the lower chamber and a gas distribution device in the form of a horizontal partition with holes along the axis of the bubble tube. In addition, these partitions are offset with respect to the plates of the upper chamber to create multi-pass channels for liquid flow from supply nozzles to recovery nozzles. The above factors reduce the variability in residence time of individual portions of liquid. By varying the number and placement of the plates in the upper chamber and the partitions in the lower chamber, a device with the desired number of passages through the tube space (which can vary from 2 to 6-10) can be produced. . However, such devices require high gas flows to prevent large amounts of liquid from entering the lower gas chamber. However, even operating with high gas flow rates, it is not possible to completely avoid liquid entering the lower chamber, which can lead to loss of reagent. Accordingly, the device disclosed in US Pat. No. 5,800,000 includes an inactive area occupied by gas. In addition, due to the possibility of blockage of the holes, the process may involve precipitation of solid deposits, high molecular weight compounds, and/or high viscosity compounds, including resins and polymers, and crystallization of one of the reaction mixture components. It is undesirable to use this equipment for the process.

In the prior art device described below, uniform gas distribution across the device cross-section (i.e., same gas concentration everywhere in the tube in the horizontal cross-section of the device) prevents the wall of the tube, located below the lower tubesheet, from the tubesheet This is achieved due to the fact that it has holes for the transition of gas entering the tube from the gas bracket formed underneath. However, the use of devices with holes in the tube wall is problematic in processes involving the formation of crystallization and precipitation reaction products or catalysis due to blockage of the holes and perturbation of the hydraulic parameters of the device. The likelihood of forming explosive gas mixtures and liquid vapors in the gas space below the lower tubesheet also limits the applicability of the device.

A gas lift apparatus disclosed in US Pat. No. 5,200,000 (published Feb. 23, 1986) comprises a vertical cylindrical housing containing upper and lower tubesheets for securing a bundle of vertical circulation and bubble tubes. The upper end of the bubble tube is positioned higher than the end of the circulation tube. To increase the reaction area and phase contact surface of the device and improve productivity by creating a stable circulation, the device is mounted above the upper tubesheet such that a gas chamber is formed in between. and an auxiliary tubesheet. The end of the bubble tube is placed in the gas phase, while the end of the circulation tube is placed in the liquid phase and a hole is provided in the circulation tube section placed in the gas chamber. The apparatus comprises a droplet remover and a separation chamber with supply and recovery nozzles for both phases and heat transfer agent. The structure of the disclosed device does not prevent liquid from entering the upper gas chamber from the circulation tube, which can impair its operation. Furthermore, the flow of gas in the circulation tube, coming from the upper gas chamber, can be disturbed as it moves to the lower part of the device under the influence of the liquid phase.

The device disclosed in US Pat. No. 4,900,000 (published Jan. 1, 1960) is designed as a vertical housing with a central circulation tube. Each tube of the device has an elongated end that extends through a perforated lower tubesheet. The lower portion of the circulation tube is below the tube cut. When gas is supplied to the device through the branch pipe, the liquid filling the cavity under the tubesheet is pushed downward, forming a gas bracket under the tubesheet, and the gas passes through all the tube holes into the bubble. state and thereby evenly distributed over the device portion. As it rises through the tube, the gas bubbles entrain the liquid and create strong circulation, which improves heat transfer. However, this document does not disclose that the device provides stable heat exchange across the device (ie the temperature gradient of the device does not change over time). Since the gas-liquid flow in the bubble tube of this device, immediately adjacent to the central circulation tube, is faster than in the other tubes, different heat and mass transfer conditions are observed in different parts of the device, resulting in a reaction Low selectivity. The processes occurring in the device are not stable even with many circulation tubes, as both the circulation and bubble tubes extend beyond the tubesheet, thereby causing gas phase build-up in the lower portion of the device.

Another conventional shell-and-tube gas lift apparatus, disclosed in US Pat. (the ends in the upper chamber are arranged at different heights), liquid phase delivery nozzles and gas phase delivery nozzles. When the gas is supplied, a gas layer forms under the tubesheet and from there the gas enters the bubble tube through the holes. Due to the density difference between the liquid phase in the circulation tube and the gas-liquid mixture in the bubble tube, strong phase circulation occurs, the gas-liquid mixture moves upward through the bubble tube, and the liquid phase moves through the circulation tube. Move downwards through. Since the tube ends are arranged at different heights, in the upper chamber the liquid phase forms layers according to the specific gravities of the components. However, Patent Document 5 does not refer to circulation stability of the flow. The effect of tube extension on the upper tubesheet of the device on liquid circulation is not supported by specific examples of this patent description. Furthermore, explosive gas mixtures can form in this space.

Therefore, with high thermal effects, i.e. formation of crystalline precipitates, polymeric compounds and/or high-viscosity compounds, or with the formation of explosive gases, high efficiency and, in particular, high selectivity of the desired product. and with high yields, no apparatus is currently known in the art that can carry out gas-liquid processes of chemical reactions.

U.S. Pat. No. 5,846,498 Russian Patent No. 2040940 Former Soviet Patent No. 1212550 Former Soviet Patent No. 129643 Former Soviet Patent No. 199087 U.S. Pat. No. 5,846,498

It is an object of the present invention to provide a bubble shell and tube gas lift apparatus for conducting gas-liquid processes that exhibits stable and uniform heat and mass transfer throughout the apparatus and steady state performance.

The technical effect of the present invention is to reduce the liquid residence time variability in the reaction zone, improve the hydraulic efficiency, and also increase the selectivity of the processes (including chemical reactions) carried out in the device. To provide a gas lift device.

Further technical effects of the present invention are processes with high thermal efficiency, processes involving the formation of solid deposits, polymeric compounds and/or highly viscous compounds, including resins and polymers, and also one of the reaction mixture components. To provide a bubble-shell-and-tube gas lift apparatus that enables processes involving crystallization.

A further technical effect of the present invention is to reduce the probability of forming an explosive mixture of gas and liquid vapors by reducing the gas space volume within the device so that it does not react with the liquid phase.

Furthermore, the device has no dead areas occupied by gas.

Furthermore, the productivity of the device is improved due to the increased volumetric efficiency of the device and the increased reaction area.

In the context of the present invention, the thermal and mass transfer stability of a device shall be interpreted as the unchanging properties (composition, temperature, flow rate, etc.) at each flow point.

Steady-state performance of the device shall be interpreted as a mode of operation in which the characteristics return to the initial state after the disturbance has been removed.

Furthermore, the variation in residence time of the liquid in the reaction zone shall be interpreted as the deviation of the residence time of the actual flow from the rated value, and the hydraulic efficiency shall be interpreted as the approximation of the plug flow device of the actual device. shall be interpreted as a characteristic.

In the context of the present invention, the term "substantially" means a deviation within an acceptable error range for a particular value determined by a person skilled in the art.

This object and technical effect is a housing having a reagent supply device and a reaction product collection device, and a heat transfer agent supply and collection device, wherein two groups of tubes are secured by upper and lower tubesheets of the housing. , one group of tubes extending beyond the lower tubesheet, a second group of tubes having tube ends substantially flush with the lower tubesheet, and the tubes of the first group of tubes extending beyond the lower tubesheet This is achieved using an apparatus comprising one or more vertical shell and tube units formed as housings that are substantially evenly distributed across the sheet.

The inventors have found that the structure and configuration of the first and second tube groups of the present invention keeps the flow direction within the tubes constant, which contributes to stable and uniform heat and mass transfer throughout the device, as well as It has been unexpectedly found that it gives a constant performance of , thereby ensuring the claimed technical effect.

A detailed description of various aspects and embodiments of the invention follows.

The tubes of the first tube group extend beyond the lower tubesheet by 10-150 mm, preferably 50-100 mm. If the length that the tubes of the first tube group extend with respect to the lower tubesheet is less than 10mm, there is a high probability that gas will enter the circulation circuit, which will disturb the hydraulics and consequently the heat and mass of the equipment. disrupt movement. Making the tubes of the first tube group longer than 150 mm relative to the lower tubesheet may increase the geometry of the device, thus increasing the amount of metal without improving device efficiency and is therefore not advisable. do not have. The extensions of the first group of tubes can be of the same length or of different lengths. It is not a requirement for the operation of the device that the extensions of the tubes of the first tube group have the same length. The determining condition is that it be longer than 10mm, which is long enough to prevent gas from entering.

The diameters of the tubes in the first tube group and the second tube group may be the same or different, but in order to increase the gas/liquid contact area, the diameter of the tubes in the first tube group should be larger than that of the tubes in the first tube group. It is preferred to use the tubes of the second group of tubes with a higher .

A prerequisite for the operation of the device is a uniform distribution of the tubes of the first tube group throughout the device, i.e. a distribution of the tubes that equalizes the velocity of the liquid phase throughout the device and eliminates stagnation zones.

The ratio between the number of tubes in the first tube group and the number of tubes in the second tube group is between 1:1.25 and 1:5. Preferably, in a horizontal cross-section of the unit, at least one of the tubes of the first group of tubes is adjacent to each of the tubes of the second group of tubes. More preferably, in the horizontal cross-section of the unit, each of the tubes of the first tube group is surrounded by a tube of the second tube group. This tube placement is achieved with a ratio of about 1:2.

In one embodiment, the tubes of the first tube group are circulation tubes and the tubes of the second tube group are bubble tubes.

The overall dimensions of the device, the number of shell-and-tube units, the number of tubes within the unit, and the total number of tubes within the device are chosen based on the requirements of the particular application of the device.

The reagent supply device includes a liquid phase supply device and a gas phase supply device, and the reaction product recovery device includes a liquid phase recovery device and a gas phase recovery device.

The apparatus is used as a reactor for various liquid phase reactions, e.g. hydrocarbon oxidation, olefin oligomerization, carboxylic acid synthesis, ethylene chlorination, hydroformylation, and also for microbiological processes. can be used as

A method for conducting a chemical reaction in a bubble shell and tube apparatus according to the present invention comprises:
- supplying a liquid phase to fill the total free volume of the tubing portion of the device;
- supplying a gas phase to the bottom of the apparatus for raising the gas to the lower tubesheet and into the tubes of the second tube group so that the tubes of the second tube group act as bubble tubes;
- moving the liquid under the influence of gas rising in the bubble tube;
- separating the gas-liquid mixture when it reaches the top of the device;
- recovering the gas phase from the device;
- withdrawing a small portion of the liquid phase while a large portion of the liquid phase begins to move downward under the force of gravity through the tubes of the first group of tubes acting as circulation tubes.

Other features and advantages of the invention will become more apparent from the preferred embodiments of the invention described in more detail with reference to the accompanying drawings. These embodiments are provided to illustrate the invention by way of example only, and therefore should not be construed as limiting the scope of the invention.

1 is a diagram of an apparatus for conducting an exothermic gas-liquid reaction according to US Pat. No. 5,846,498; FIG. 1 is a diagram of an apparatus for carrying out gas-liquid chemical and heat and mass exchange processes according to Russian Patent No. 2040940; FIG. 1 is a diagram of a gas lift device according to the former USSR patent No. 1212550; FIG. 1 is a diagram of a device according to the former USSR patent No. 129643; FIG. 1 is a diagram of a device according to the former USSR patent No. 199087; FIG. 1 is a schematic diagram of the structure of a device according to the invention; FIG. FIG. 4 is a schematic diagram of the tube arrangement of the device according to Comparative Example 2; FIG. 4 is a schematic diagram of the tube arrangement of the device according to Comparative Example 3; FIG. 4 is a schematic diagram of the tube arrangement of the device according to Example 4; FIG. 11 is a schematic diagram of the tube arrangement of the device according to Example 5; 1 is a diagram of a unit of a device according to the invention; FIG. FIG. 10 is a view of a glass device with tubes of the same length according to Comparative Example 6;

The apparatus according to the invention, shown schematically in FIG. 6, comprises a single vertical shell-and-tube unit 1 with circulation tubes 3 and bubble tubes 4 fixed to a tubesheet 2 . The lower part of the apparatus comprises a liquid supply device 5 and a gas supply device 6 . The upper part of the apparatus comprises a gas phase recovery device 7 and a liquid phase recovery device 8 . The inter-tube space of the device is provided with heat transfer agent circulation nozzles 9 and 10 . Hereinafter, supply and withdrawal devices refer to any conventional means for supplying and withdrawing streams, such as nozzles, injectors, and the like.

The process is carried out in the apparatus of the invention in the following manner.
1. A liquid phase is fed through the liquid supply device 5 to completely fill the total free volume of the tube section of the device.
2. The gas phase is then fed through the gas feeding device 6 into the lower part of the apparatus.
3. Gas rises to tubesheet 2 and then enters bubble tube 4.
4. The liquid begins to move upwards in the bubble tube under the influence of the gas.
5. The gas-liquid mixture is separated when it reaches the top of the device.
6. The gas phase is withdrawn from the apparatus through the gas withdrawal device 7.
7. A small portion of the liquid phase is recovered through the liquid recovery device 8 and a large portion of the liquid phase begins to move downwards in the circulation tube 3 under the force of gravity.

Uniform distribution of the circulation tubes ensures equal velocity of liquid through all bubble tubes, resulting in equal conditions for heat and mass transfer processes taking place throughout the device. A heat transfer agent is circulated through nozzles 9 and 10 to ensure heat transfer in the inter-tube space of the device.

[Example]
(Comparative Example 1. Use of devices with tubes of the same length)
The test was conducted in a steel apparatus comprising an 80 mm diameter vertical shell and tube unit with 19 725 mm long, 13 x 1.4 mm diameter tubes secured to a tube sheet. The lower part of the device is equipped with liquid and gas feed nozzles. The upper part of the device is equipped with gas and liquid phase recovery nozzles. The inter-tube space of the device is equipped with heat transfer agent circulation nozzles (see Figure 2).

The tests were carried out at atmospheric pressure. Cyclohexane was used as the liquid phase and nitrogen as the gas phase. The number of tubes in bubbling mode was visually determined by the gas bubbles emerging every minute. Results were then averaged over 30 minute time intervals and conclusions drawn for each tube mode and activity.

In the absence of tube extension, a chaotic alternation of circulation and bubble tubes was observed. Also, during operation, the circulation tube may bubble, and vice versa. Moreover, the number of bubble tubes varied from time to time. All this indicates that the gas-liquid mixture flow conditions are much more unstable. This led to local abrupt changes in dissolved gas concentration and temperature, which were also observed visually. It should be noted that in this device about 60% of the tubes are impervious to gas, which means that liquid does not move in these tube portions and stagnation areas are formed.

(Comparative Example 2. Use of a device with a single extension tube)
The test was performed with the apparatus described in Example 1, with the difference that the centrally located tube of the apparatus extends 50 mm below the tubesheet (see Figure 7).

The extension of one central tube strictly defines this tube as a circulation tube. However, the capacity of this tube is insufficient for stable circulation of liquid throughout the device unit. Furthermore, some of the bubble tubes are in a state of chaotic liquid circulation, i.e. they alternately become circulation tubes and bubble tubes, which, as in Example 1, dissolve. This leads to local abrupt changes in the concentration and temperature of the gas.

(Comparative Example 3. Use of a device with three extension tubes)
The test was performed in the apparatus described in Example 1, with the difference that three tubes, alternately arranged around the central tube, extended 50 mm downward beyond the tubesheet. (See Figure 8).

By increasing the number of circulation tubes to three and distributing them throughout the device, the flow was fairly stable. All bubble tubes worked only as bubble tubes. However, the gas throughput rate of the bubble tube, and thus the liquid throughput rate, differed considerably, which led to destabilization of the heat and mass transfer conditions within the tube space of the device.

(Example 4. Using a device with 3 circulation tubes placed near the central tube and 3 tubes in the outer row occluded)
The test was performed on the apparatus described in Example 1, with the difference that three tubes, alternately arranged around the central tube, extended 50 mm beyond the tubesheet and The three tubes in the outer row are blocked (see Figure 9).

Distributing the circulation tubes in this way ensures consistent performance of the unit with an average liquid circulation rate throughout the device (i.e., the average liquid circulation rate is substantially constant throughout the device). . This results in uniform heat and mass transfer conditions throughout the device.

(Example 5. Using a device with 3 circulation tubes placed near the center tube and 3 circulation tubes in the outer row)
The test was performed with the apparatus described in Example 1, with the difference that the three tubes, spaced alternately around the central tube, extend 50mm beyond the tubesheet. (see Figure 9).

Increasing the number of circulation tubes to six leads to a considerable increase in the liquid circulation rate. In addition, the flow structure is stationary, ie, the media composition, local velocities and physical properties at each point of the flow in the working area of the device remain substantially constant over time. This results in uniform heat and mass transfer conditions throughout the device. Compared to Example 4, the liquidus velocity is increased, thereby increasing the efficiency of heat removal from the device surface.

(Comparative Example 6. Test on mass transfer in a glass device with tubes of the same length)
The test consists of a 2 liter volume of glass with a vertical unit having two metal tubesheets of 100mm diameter and 19 glass tubes of 800mm length and 10x1.5mm diameter fixed to these tubesheets. done on the device. All tubes extended beyond the tubesheet. The lower part of the device is equipped with liquid and gas feed nozzles. The top of the device is equipped with gas and liquid phase recovery nozzles (see Figure 2).

The tests were carried out at atmospheric pressure. An aqueous solution of NaOH was used as the liquid phase and carbon dioxide was used as the gas phase. The liquid velocity was set by a pump and the outlet liquid concentration was measured by a pH meter. Gas was delivered from the cylinder through a flow meter.

Each neutralization reaction proceeds at high speed and the process limiting factor is the transfer of carbon dioxide to the liquid. This example of the neutralization reaction of carbonic acid with a strong alkali allows us to assess the effectiveness of mass transfer between gas and liquid phases in the apparatus.

The test was conducted as follows. The device was completely filled with liquid by the pump. The required constant flow rate of the liquid phase (200 ml/min) was then set and the gas injection started (500 ml/min). pH values were detected every 2 minutes. Steady state operation was determined to be established when there was no change in pH value at the device outlet for 10 minutes.

With the above parameters, the time to stable steady state operation at pH value = 10.2 was 40 minutes. Furthermore, as in Example 1, chaotic motion of the two-phase flow was observed.

Example 7. Mass Transfer Test in a Glass Apparatus with 3 Circulation Tubes Near the Center Tube and 3 Circulation Tubes in the Outer Rows
The test consists of a 2 liter volume of glass with a vertical unit having two metal tubesheets of 100mm diameter and 19 glass tubes of 800mm length and 10x1.5mm diameter fixed to these tubesheets. done on the device. As in Example 5, a portion of the tube extended beyond the lower tubesheet. The lower part of the device was equipped with liquid and gas feed nozzles. The top of the device was equipped with gas and liquid phase recovery nozzles (see Figure 9).

The tests were carried out at atmospheric pressure. An aqueous solution of NaOH was used as the liquid phase and carbon dioxide was used as the gas phase. The liquid velocity was set by a pump and the outlet liquid concentration was measured by a pH meter. Gas was delivered from the cylinder through a flow meter.

The test was conducted as follows. The device was completely filled with liquid by the pump. The required constant flow rate of the liquid phase (200 ml/min) was then set and gas injection (500 ml/min) was started. pH values were detected every 2 minutes. Steady state conditions were determined to be established when there was no change in pH value at the device outlet for 10 minutes.

With the above parameters, the time to stable steady state operation at pH value = 9.4 was 30 minutes.

As can be seen from Examples 6 and 7, the mass transfer process is more efficient in the device of the present invention because the stable pH value is lower. A lower pH indicates that the mass exchange process (reaction) proceeds faster and more completely in the gas-liquid system. In addition, the time to reach equilibrium is reduced by 25%, due to the absence of stagnation zones that can cause significant jumps in concentration in the liquid phase and the uniform We show that the device has a similar velocity field.

(Comparative Example 8. Use of a device with tubes of the same length as a reactor for the trimerization of ethylene)
The test was carried out in a steel reactor equipped with a vertical shell and tube unit of 80 mm diameter with 19 tubes of 725 mm length and 13 x 1.4 mm diameter fixed in a tube sheet. The lower part of the reactor is equipped with liquid and gas feed nozzles. The top of the reactor is equipped with gas and liquid phase recovery nozzles. The inter-tube space of the reactor is equipped with a heat transfer agent circulation nozzle (see Figure 2).

The ethylene trimerization reaction was carried out under a pressure of 14 bar. As liquid phase, cyclohexane was used in addition to the homogeneous catalyst complex, and as gas phase, ethylene was used. Concentrations of the reaction product hexene-1 and by-products were measured by periodic sampling at the reactor outlet. A gas chromatograph was used as the analytical control method.

The concentration of hexene-1 at the reactor outlet varied within the range of 6-7% by weight with a selectivity of 96-97%.

Example 9. Use of a device with three circulation tubes located near the central tube and three circulation tubes in the outer row as a reactor for the trimerization of ethylene.
The test was performed with the apparatus described in Example 8, with the difference that the three tubes, spaced alternately around the central tube, extend 50mm beyond the tubesheet. (see Example 5).

The concentration of hexene-1 at the reactor outlet varied, as in Example 8, in the range of 6-7% by weight with a selectivity of 96-97%.

The difference between Examples 8 and 9 is almost imperceptible due to the relatively small reactor tube volume, which is about 60% of the total reaction volume in the test.

1 vertical shell and tube unit
2 tube sheet
3 circulation tube
4 bubble tube
5 Liquid supply device
6 gas supply device
7 gas phase recovery device, gas recovery device
8 liquid recovery device, liquid recovery device
9 Heat transfer agent circulation nozzle
10 Heat transfer agent circulation nozzle

Claims (15)

A bubble shell and tube apparatus for the oligomerization of ethylene comprising a reagent supply device at the bottom of said bubble shell and tube apparatus and a reaction product recovery device at the top of said bubble shell and tube apparatus, heat transfer agent supply and In a bubble shell and tube apparatus comprising at least one vertical shell and tube unit formed as a housing having a retrieval device and first and second groups of tubes secured to the upper and lower tubesheets , the tubes of the first tube group extending beyond the lower tubesheet and the tubes of the second tube group having their ends substantially flush with the lower tubesheet; arranged such that the tubes of the first group of tubes are substantially evenly distributed across the lower tubesheet;
The tubes of the first tube group are arranged symmetrically with respect to two lines passing through the center of the lower tube sheet and perpendicular to each other in the horizontal cross section of the vertical shell-and-tube unit. Bubble shell and tube device. 2. The bubble shell and tube device of claim 1, comprising a single shell and tube unit. 2. The bubble shell-and-tube apparatus of claim 1, comprising more than one shell-and-tube unit. 2. The bubble shell and tube apparatus of claim 1, wherein the tubes of the first group of tubes extend 10-150mm beyond the lower tubesheet. 5. The bubble shell and tube apparatus of claim 4, wherein the tubes of the first group of tubes extend 50-100mm beyond the lower tubesheet. 2. The bubble shell and tube device according to claim 1, wherein the ratio of the number of tubes in said first tube group to the number of tubes in said second tube group is 1:1.25 to 1:5. 2. The bubble shell-and-tube apparatus of claim 1, wherein in a horizontal cross-section of the vertical shell-and-tube unit, each tube of the first tube group is surrounded by a tube of the second tube group. . 2. The bubble shell-and-tube apparatus of claim 1, wherein in a horizontal cross-section of the vertical shell-and-tube unit, at least one tube of the first tube group is adjacent to each tube of the second tube group. . 2. The bubble shell and tube apparatus of Claim 1, wherein the tubes of the first group of tubes have the same length or different lengths. 2. The bubble shell and tube apparatus of claim 1, wherein the tubes of the first tube group and the tubes of the second tube group have the same diameter. 2. The bubble shell and tube apparatus of claim 1, wherein the diameter of the tubes of the first tube group is greater than the diameter of the tubes of the second tube group. 2. The bubble shell and tube apparatus of claim 1, wherein the diameter of the tubes of the second group of tubes is greater than the diameter of the tubes of the first group of tubes. 2. The bubble shell and tube apparatus of claim 1, comprising a bubble shell and tube reactor. 2. The bubble shell and tube apparatus according to claim 1, wherein the tubes of the first tube group are circulation tubes and the tubes of the second tube group are bubble tubes. 2. The bubble shell and tube apparatus of claim 1, wherein said reagent supply device comprises a liquid phase supply device and a gas phase supply device, and said reaction product recovery device comprises a liquid phase recovery device and a gas phase recovery device.

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