KR102575566B1 - Bubble shell-and-tube device - Google Patents

Abstract

The present invention relates to equipment for gas-liquid processing. The bubble shell-and-tube apparatus includes at least one vertical shell-and-tube unit formed as a housing with reagent supply devices and reaction product withdrawal devices, heat transfer medium supply and withdrawal devices , and a first tube group and a second tube group secured within the upper tube sheet and the lower tube sheet. The tubes of the first tube group extend beyond the lower tube sheet, the tubes of the second tube group are positioned such that their ends are substantially flush with the lower tube sheet, the tubes of the first tube group are substantially evenly distributed throughout the tube sheet. When implementing the method for carrying out a chemical reaction in a bubble shell-and-tube apparatus according to the present invention, the tubes of the first tube group act as circulation tubes, and the tubes of the second tube group act as bubble tubes. works (Fig. 6).

Description

Bubble shell-and-tube device

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

In most gas-liquid processes, one or more of the starting reagents are in the gaseous state, and for the reaction to occur, the reagents must be converted to the liquid state or to the boundary between the two phases. and this requires high mass transfer rates. Moreover, processes carried out in liquid and gaseous phases often involve high heat release or absorption, which requires efficient heat exchange between the mixture and the heat transfer medium.

In addition, the uniformity of the conditions for carrying out heat and mass transfer throughout the apparatus is essential because a local increase or decrease in the reaction mixture temperature or concentration of reagents can reduce the selectivity and conversion of the process and the rate of reaction. very important. Uniformity of the reaction conditions can be achieved by using equipment with tubes that are evenly distributed in volume, i.e., distributed to equalize the liquid phase flow rate throughout the system and eliminate stagnant zones.

A conventional shell-and-tube apparatus for conducting exothermic gas-liquid processes (reactions) is disclosed in US 5,846,498 (published Dec. 8, 1998). The device includes a hollow draft tube disposed therein. The tube houses the impeller means for effecting recirculation of the liquid through the tube and into the lower mixing chamber below. A liquid flow is introduced into the device through a supply line and a gas is introduced above the liquid level via the line. The device exhibits improved heat transfer, high productivity and selectivity due to the use of forced circulation created in the impeller means.

However, the fixation of a fast-spinning structure by a single fixing point (only in the upper position) is technically problematic, since during rotation the impeller can become misaligned from the axis of rotation under tangential forces. Therefore, special sealing materials will be required for operation of the impeller shaft at high pressure. Moreover, a high velocity of the liquid is required to create a gas-liquid flow descending through the center tube, which will result in additional energy loss in rotation of the impeller. The length of the device will be severely limited despite the significant rotational speed of the impeller.

RU2040940 (published on August 9, 1995) discloses a device for carrying out gas-liquid chemical and heat and mass transfer processes with high thermal effect, which has a multi-pass through working area. Through the provision of the pass, it is possible to reduce the residence time dispersion (ie, the deviation of the residence time of the actual flow from the rated value) of the liquid reagent in the device. The device includes 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, the tubes being tube sheets. a cylindrical vertical housing fixed within; It is accommodated in an upper chamber with vertical plates and a lower chamber with a gas distribution device. The housing includes heat transfer medium supply and withdrawal nozzles, and the lower chamber has a gas supply nozzle and a drain nozzle. The device is characterized by providing a gas distribution device in the form of a vertical partition and a horizontal partition with holes along the axis of the bubble tubes. Moreover, the partitions are offset relative to the plates in the upper chamber to create a multi-pass channel for liquid flow from the supply nozzle to the draw nozzle. The above factors reduce the residence time dispersion of the individual portions of the liquid. By varying the number and placement of the plates in the upper chamber and the partitions in the lower chamber, it is possible to create a device with any number of passes through the tube space, the number of passes varying from 2 to 6-10. . However, these devices require high gas flow rates to prevent large amounts of liquid from entering the lower gas chamber. However, even when operating at a high gas flow rate, liquid cannot be completely prevented from entering the interior of the lower chamber, which leads to loss of reagents. Consequently, the device disclosed in RU2040940 comprises inactive zones occupied by gas. Moreover, in processes which, due to possible clogging of the pores, may involve precipitation of solid precipitates, polymers and/or high viscosity compounds, including resins and polymers, and in processes involving crystallization of one of the components of the reaction mixture, such devices It is not advisable to use

In the conventional devices described below, a uniform gas distribution across the device cross-section (i.e., the gas concentration is the same at any point of the tube in the horizontal cross-section of the device) is a tube disposed below the lower tube sheet. This is obtained due to the fact that their walls have holes for the transition of gas entering the tubes from the gas blanket formed under the tube sheet. However, the use of devices with holes in the tube walls is problematic in processes involving the formation of crystallized and precipitated reaction products or catalysts due to plugging of the holes and perturbation of the hydrodynamic parameters of the device. The possibility of formation of explosive gas mixtures and liquid vapors in the gas space below the lower tube sheet also limits the applicability of the devices.

A gas lift apparatus disclosed in SU1212550 (published Feb. 23, 1986) includes a vertical cylindrical housing housing upper and lower tube sheets to hold a vertical bundle of circulation and bubble tubes. The upper ends of the bubble tubes are disposed higher than the ends of the circulation tubes. To increase the reaction zone and phase contact surface of the device and improve productivity by creating stable circulation, the device further includes an auxiliary tube sheet mounted above the top tube sheet so that a gas chamber is formed therebetween. The ends of the bubble tubes are disposed in the gas phase, the ends of the circulation tubes are disposed in the liquid phase, and holes are provided in the circulation tube sections disposed in the gas chamber. The apparatus includes a drop eliminator and a separation chamber with supply and withdrawal nozzles for the phases and heat transfer medium. The structure of the disclosed device does not preclude the ingress of liquid from the circulation tubes into the upper gas chamber, which deteriorates its operation. Additionally, the flow within the circulating tubes of gas from the upper gas chamber may be impeded under the influence of the liquid phase as it travels down the device.

The device disclosed in SU129643 (published on January 1, 1960) is designed as a vertical housing with a central circulation tube. Each tube of the device has an elongated end extending through a lower tube sheet with holes. The lower section of the return tube is below the tube cut. When gas is supplied to the device through the branch tube, the liquid filling the cavity under the tube sheet is forced downward, and a gas blanket is formed under the tube sheet; The gas is bubbled through the orifices of all the tubes and is thereby evenly distributed over the entire cross-section of the device. While rising through the tubes, gas bubbles entrain the liquid and create strong circulation, which enhances heat transfer. However, the document does not disclose that the device provides a stable heat exchange (ie, a temperature gradient that does not change with time within the device). Because the gas-liquid flow in the bubble tubes, directly adjacent to the central circulation tube, of this device has a higher velocity than in the other tubes, different heat and mass transfer conditions will be observed in different parts of the device. , a reduced reaction selectivity will be observed as a result. Since both the circulation tubes and the bubble tubes extend beyond the tube sheet, thereby causing the accumulation of gas phase, the processes taking place within the apparatus will not be stable despite the increased number of circulation tubes.

Another conventional shell-and-tube gas flotation device disclosed in SU199087 (published on Jan. 1, 1967) is: an upper chamber and a lower chamber with jackets, tube sheets and circulation tubes passing through them, and bubble tubes. , and a liquid supply nozzle and a gaseous supply nozzle, wherein the ends of the bubble tubes in the upper chamber are disposed at different levels. During gas filling, a layer of gas is formed below the tube sheet, from which gas enters the bubble tubes through holes. Due to the difference in density between the liquid phase in the circulation tubes and the gas-liquid mixture in the bubble tubes, strong phase circulation occurs: the gas-liquid mixture moves upward through the bubble tubes, and the liquid phase moves downward through the circulation tubes. . Since the tube ends are located at different levels, the liquid phase in the upper chamber is stratified according to the specific gravity of the components. However, SU199087 is silent about flow circulation stability. The effect of the amount of tube extension above the top tube sheet of the device on liquid circulation is not supported by the specific examples in the description of this patent. Furthermore, explosive gas mixtures may form within this space.

Therefore, in the present state of the art, it is possible to carry out gas-liquid processes with high thermal effects, the formation of crystalline precipitates, polymers and/or highly viscous compounds, or with the formation of explosive gases, and with high efficiency. There is no known device with high selectivity and high yield of the desired product, especially when the process is a chemical reaction.

An object of the present invention is a bubble shell-and-tube gas-lift device for performing gas-liquid processes, exhibiting stable and uniform heat and mass transfer, and steady performance throughout the device. gas-lift apparatus).

The technical effect of the present invention is to reduce the residence time dispersion of the liquid in the reaction zone, improve the hydrodynamic efficiency, and increase the selectivity of the process carried out in the apparatus (including chemical reaction) bubble shell-and- provision of a tube gas-lift device.

An additional technical effect of the present invention is a process with pronounced thermal effects, as well as with the formation of solid precipitates, polymers and/or highly viscous compounds, including resins and polymers, and crystallization of one of the components of the reaction mixture. It is the provision of a bubble shell-and-tube gas-lift device that enables processes to

A further technical effect of the invention is that the possibility of formation of explosive mixtures of gas and liquid vapors is reduced due to the reduced volume of the gas space in the device, which does not react with the liquid phase.

Moreover, the present invention has no inert zone occupied by gas.

Moreover, the productivity of the device is improved because of the device's elevated volumetric efficiency and elevated reaction zone.

In the context of the present invention, the stability of heat and mass transfer within the device will be interpreted as the constancy of the properties (composition, temperature, flow rate, etc.) at each flow point over time.

A stable performance of the device will be interpreted as an operating mode in which the characteristics return to their initial state after the disturbance is removed.

Also, the residence time dispersion of the liquid within the reaction zone will be interpreted as the deviation of the residence time of the actual flow from the rated value, and the hydrodynamic efficiency will be interpreted as the approach characteristics of the actual device as a plug-flow device.

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.

Objects and technical effects are obtained by the use of the apparatus, which comprises one or more vertical shell-and-tube units formed as a housing with reagent supply devices and reaction product withdrawal devices, heat transfer medium supply and withdrawal devices, and two tube groups held together by tube sheets in a top and a bottom in the housing, one tube group extending beyond the lower tube sheet and a second tube group substantially adjacent to the lower tube sheet With the tube ends of the same height, the tubes of the first tube group are substantially evenly distributed throughout the tube sheet.

The inventors have unexpectedly discovered that the structure of the present invention and the arrangement of the first and second tube groups maintains a constant flow direction within the tubes, which is stable and uniform heat and mass transfer throughout the device and the efficiency of the device. It provides stable performance, thereby ensuring the claimed technical effects.

A detailed description of various aspects and embodiments of the present invention will follow below.

The tubes of the first tube group extend 10-150 mm, preferably 50-100 mm, beyond the lower tube sheet. If the extension of the length of the tubes of the first tube group relative to the lower tube sheet is less than 10 mm, the possibility of gas slippage through the circulation circuit increases, which disturbs the hydrodynamics and, as a result, the device Impedes heat and mass transfer within. Because extending the tubes of the first tube group more than 150 mm relative to the lower tube sheet may increase the geometrical dimensions of the device and consequently increase the metal content without improving the device efficiency; Not desirable. The extensions of the tubes of the first tube group may be of the same or different lengths. The same length of the extensions of the tubes of the first tube group is not a prerequisite for the operation of the device. The determining condition is a length of at least 10 mm sufficient to prevent gas from entering the tubes of the first tube group.

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

An obligatory requirement for the operation of the device is a uniform distribution of the tubes of the first tube group throughout the device, ie a distribution of tubes equalizing the velocity of the liquid phase and eliminating stagnant zones throughout the device. am.

The ratio of the number of tubes of the first and second tube groups ranges from 1:1.25 to 1:5. Preferably, in a horizontal section of the unit, at least one of the tubes of the first tube group is adjacent to each of the tubes of the second tube group. More preferably, in a horizontal section of the unit, each of the tubes of the first tube group is surrounded at the periphery by the tubes of the second tube group. This batch of tubes is obtained at a ratio of approximately 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 selected based on the needs of the particular application of the device.

The reagent supply devices include a liquid phase supply device and a gas phase supply device, and the reaction product withdrawal devices include a liquid phase withdrawal device and a gas phase withdrawal device.

The device can be employed as a reactor for carrying out various liquid-phase reactions, such as hydrocarbon oxidation, olefin oligomerization, synthesis of carboxylic acids, ethylene chlorination, hydroformylation, and as a device for microbiological processes, can

A method for carrying out a chemical reaction in a bubble shell-and-tube apparatus according to the present invention is:

- supplying a liquid phase to fill the entire free volume in the tubular part of the device;

- supplying gaseous phase to the lower part of the device, so that the gas rises up to the lower tube sheet and enters the tubes of the second tube group, so that the tubes of the second tube group act as bubble tubes;

- providing movement of the liquid upward through the bubble tubes under the influence of the gas;

- when reaching the top of the device, the gas-liquid mixture is separated;

- withdrawing the weather from the device; and

- while withdrawing a smaller part of the liquid phase, a greater part of the liquid phase begins to move downward under gravity through the tubes of the first tube group acting as circulation tubes.

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

Figure 1 shows an apparatus for carrying out an exothermic gas-liquid reaction according to US 5,846,498.
Figure 2 shows a device for carrying out gas-liquid chemical and heat and mass exchange processes according to RU2040940.
3 shows a gas lift device according to SU1212550.
4 shows a device according to SU129643.
5 shows a device according to SU199087.
6 schematically shows the structure of the device according to the present invention.
7 schematically shows the arrangement of the tubes in the device according to Comparative Example 2.
8 schematically shows the arrangement of the tubes in the device according to Comparative Example 3.
9 schematically shows the arrangement of the tubes in the device according to Comparative Example 4.
10 schematically shows the arrangement of the tubes in the device according to Comparative Example 5.
11 shows a unit of a device according to the invention.
12 shows a glass apparatus with equal length tubes according to Comparative Example 6.

The apparatus according to the invention, shown schematically in FIG. 6 , is a single vertical shell-and-tube unit with circulation tubes 3 and bubble tubes 4 fixed in a tube sheet 2 ( 1) includes The lower part of the device includes a liquid supply device (5) and a gas supply device (6). The upper part of the device comprises a gas phase withdrawal device 7 and a liquid phase withdrawal device 8 . The space between the tubes of the device contains heat transfer medium circulation nozzles (9, 10). Supply and withdrawal device refers hereinafter to any conventional means for supplying and withdrawing flow, eg nozzles, injectors, etc.

The process is carried out in the apparatus of the present invention in the following manner.

1. The liquid phase is supplied through the liquid supply device 5 to completely fill the entire free volume in the tube portion of the device;

2. The gas phase is then supplied to the lower part of the device through the gas supply device 6;

3. The gas rises up to the tube sheet (2) and then enters the bubble tubes (3);

4. The liquid starts moving upward through the bubble tubes under the influence of the gas;

5. Upon reaching the top of the device, the gas-liquid mixture separates;

6. Gas phase is withdrawn from the device via gas withdrawal device 7;

7. A small part of the liquid phase is withdrawn through the liquid withdrawal device 8, and a large part of the liquid phase begins to move downward through the circulation tubes 3 under gravity;

The uniform distribution of the circulation tubes ensures the same velocity of the liquid through all the bubble tubes and, consequently, the same conditions for the heat and mass transfer processes carried out throughout the device. To ensure heat transfer in the space between the tubes of the device, a heat transfer medium is circulated through the nozzles (9, 10).

yes

Comparative Example 1. Use of a device containing 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 tubes 725 mm long and 13 x 1.4 mm in diameter fixed in a tube sheet. The lower part of the device contains liquid and gas supply nozzles. The top of the device contains gas and liquid phase withdrawal nozzles. The space between the tubes of the device contains heat transfer medium circulating nozzles (see Fig. 2).

The test was conducted at atmospheric pressure. Cyclohexane was used as the liquid phase and nitrogen was used as the gas phase. The number of tubes in bubbling mode was determined visually every minute by levitating gas bubbles. Results were then averaged over a 30 min time interval, and conclusions were drawn regarding the mode and activity of each tube.

Without elongation of the tubes, a chaotic alternation of circulation and bubble tubes was observed. Also, in operation, the circulation tube could be bubbled and vice versa. Moreover, the number of bubble tubes was different at different times. All of these represent the instability of the gas-liquid mixture flow state over time. This leads to local jumps in the concentration and temperature of dissolved gases, which were observed visually. It should be noted that this device contains approximately 60% of the tubes are gas impermeable. This means that in some of the tubes no movement of the liquid occurs and stagnant zones are formed.

Comparative Example 2. Use of a device comprising a single elongated tube

The test was performed in the device described in Example 1, but with the difference that the tube placed in the center of the device extended 50 mm below the tube sheet (see FIG. 7).

The extension of the central tube strictly defines that this tube is a circulation tube. However, the handling capacity of the tube is insufficient to provide stable circulation of the liquid throughout the device unit. Moreover, a portion of the bubble tubes enter into a state of chaotic circulation of the liquid, that is, alternately act as circulation tubes or bubble tubes, which, as in Example 1, causes local jumps in the concentration and temperature of the dissolved gas. continues

Comparative Example 3. Apparatus Containing Three Elongated Tubes

The test was performed in the apparatus described in Example 1, but with the difference that the three tubes, spaced one by one around the central tube, extend 50 mm downward beyond the tube sheet (see FIG. 8).

The increase in the number of circulation tubes to three and their distribution throughout the device significantly stabilized the flow. All bubble tubes operated as bubble tubes only. However, the processing rates of gas and liquid in the bubble tubes were significantly different, leading to destabilization of heat and mass transfer conditions in the tube space of the device.

Example 4. Use of a device comprising three circulation tubes disposed close to the central tube, with the three tubes in the outer row blocked off.

The test was performed in the device described in Example 1, with the difference that the three tubes, spaced one around the center tube, extend 50 mm beyond the tube sheet, and the three tubes in the outer row are closed (see FIG. 9).

This distribution of circulation tubes ensures stable performance of the unit with an average circulation rate of liquid throughout the entire system (i.e., the average liquid circulation rate is substantially stable over time throughout the system, which is uniform throughout the system). heat and mass transfer conditions.

Example 5. Use of a device comprising three circulating tubes positioned close to the central tube and three circulating tubes in an outer row.

The test was performed in the apparatus described in Example 1, but with the difference that the three tubes, spaced one by one around the central tube, extend 50 mm beyond the tube sheet (see FIG. 9).

An increase in the number of circulation tubes to six leads to a significant increase in the liquid circulation rate. Moreover, the flow structure is stable, i.e., the composition, local velocity and physical properties of the medium at each point in the flow within the operating region of the device remain substantially constant over time. This results in uniform blood 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 for Mass Transfer in Glass Apparatus Containing Tubes of Equal Length.

The test was performed on a glass apparatus with a volume of 2 liters comprising a vertical unit having two metal tube sheets of 100 mm in diameter together with 19 glass tubes of 800 mm in length and 10 x 1.5 mm in diameter, fixed in the tube sheets. was performed within All tubes extend beyond the tube sheet. The lower part of the device contains liquid and gas supply nozzles. The top of the device contains gas phase and liquid phase extraction nozzles (see Fig. 2).

The test was conducted at atmospheric pressure. Aqueous NaOH solution was used as the liquid phase and carbon dioxide was used as the gas phase. The liquid rate was set by a pump and the liquid concentration at the outlet was measured with a pH meter. Gas was supplied from the cylinder through a flow meter.

Each of the neutralization reactions proceeds at a high rate, and the process limiting factor is the transition of carbon dioxide to liquid. By way of example of neutralization reaction of carbonic acid by strong alkali, it is possible to estimate the efficiency of mass transfer between gas phase and liquid phase in the device.

The test was performed in the following manner: The device was completely filled with liquid through the pump. Then, the required constant flow rate of the liquid phase (200 ml/min) was set, and gas injection (500 ml/min) was started. pH values were detected every 2 minutes. Establishment of steady-state operation was fixed at the time at which no change in pH value occurred within 10 minutes at the outlet of the device.

With the above parameters, the time to steady-state operation with a constant pH value of 10.2 was 40 minutes. Moreover, chaotic movement of the two-phase flow was observed as in Example 1.

Example 7. Test for mass transfer in a glass apparatus comprising three circulation tubes in an outer row and three circulation tubes disposed adjacent to a central tube.

The test was performed on a glass apparatus with a volume of 2 liters comprising a vertical unit having two metal tube sheets of 100 mm in diameter together with 19 glass tubes of 800 mm in length and 10 x 1.5 mm in diameter, fixed in the tube sheets. was performed within Some of the tubes extend down beyond the tube sheet as in Example 5. The lower part of the device contained liquid and gas supply nozzles. The top of the device includes gas phase and liquid phase extraction nozzles (see Fig. 9).

The test was conducted at atmospheric pressure. Aqueous NaOH solution was used as the liquid phase and carbon dioxide was used as the gas phase. The liquid rate was set by a pump and the liquid concentration at the outlet was measured with a pH meter. Gas was supplied from the cylinder through a flow meter.

The test was performed in the following manner: The device was completely filled with liquid through the pump. Then the required constant flow rate of the liquid phase (200 ml/min) was set, and gas injection (500 ml/min) was started. pH values were detected every 2 minutes. Establishment of steady-state conditions was fixed at the time at which no pH value change occurred within 10 minutes at the outlet of the device.

With the above parameters, the time to steady-state operation with a constant pH value of 9.4 was 30 minutes.

As can be seen from Examples 6 and 7, the mass transfer processes are more efficient because of the lower constant pH value in the device of the present invention. A decrease in pH indicates that mass-exchange processes (reactions) in the gas-liquid system become faster and more complete. Additionally, the time to equilibrium is reduced by 25%, which means that there are no stagnant zones that can cause appreciable jumps in the concentration of the liquid phase, and that the device contains a uniform velocity field that allows efficient mass transfer in the liquid phase. point

Comparative Example 8. Use of an apparatus comprising tubes of the same length as a reactor for ethylene trimerization.

The test was conducted in a steel reactor comprising an 80 mm diameter vertical shell-and-tube unit with 19 tubes 725 mm long and 13 x 1.4 mm in diameter fixed in a tube sheet. The lower part of the reactor contains liquid and gas supply nozzles. The top of the reactor contains gas and liquid phase withdrawal nozzles. The space between the tubes of the reactor contains heat transfer medium circulation nozzles (see Fig. 2).

The ethylene trimerization reaction was carried out under a pressure of 14 bar. Cyclohexane to which the homogeneous catalyst complex was added was used as the liquid phase and ethylene was used as the gas phase. Concentrations of the reaction product, hexene-1, and by-products were determined by periodic sampling at the reactor outlet. Gas chromatography was used as an 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 an apparatus comprising three circulating tubes disposed close to the central tube and three circulating tubes in an outer row as a reactor for ethylene trimerization.

The test was performed in the apparatus described in Example 8, but with the difference that the three tubes, spaced one around the center tube, extend 50 mm beyond the tube sheet (see Example 5).

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

The difference between the tests in Examples 8 and 9 is negligible due to the relatively small reactor tube volume, which is approximately 60% of the total reaction volume in the tests.

Claims (20)

As a bubble shell-and-tube apparatus for the oligomerization of ethylene,
At least one vertical shell-and-tube unit formed as a housing having reagent supply devices located at the bottom of the device and reaction product withdrawal devices located at the top of the device, heat transfer medium supply and withdrawal devices, and an upper tube sheet ( tube sheet) and a first tube group and a second tube group fixed in the lower tube sheet,
The tubes of the first tube group extend beyond the lower tube sheet, the tubes of the second tube group are positioned such that their ends are substantially flush with the lower tube sheet, the tubes of the first tube group are substantially uniformly distributed throughout the tube sheet;
In a horizontal section of the unit, the tubes of the first tube group are arranged symmetrically with respect to two mutually perpendicular lines passing through the center of the lower tube sheet;
characterized in that the tubes of the first tube group and the second tube group are arranged so that the ends of the tubes are substantially flush with the upper tube sheet. According to claim 1,
A bubble shell-and-tube device comprising one single shell-and-tube unit. According to claim 1,
A bubble shell-and-tube device comprising more than one shell-and-tube unit. According to claim 1,
wherein the tubes of the first tube group extend 10-150 mm beyond the lower tube sheet. According to claim 4,
The tubes of the first tube group extend 50-100 mm beyond the lower tube sheet, a bubble shell-and-tube device. According to claim 1,
wherein the ratio between the number of tubes in the first tube group and the number of tubes in the second tube group ranges from 1:1.25 to 1:5. According to claim 1,
wherein in a horizontal section of the unit, each of the tubes of the first tube group is surrounded at the periphery by the tubes of the second tube group. According to claim 1,
wherein in a horizontal section of the unit, at least one tube of the first tube group is adjacent to each tube of the second tube group. According to claim 1,
wherein the tubes of the first tube group have the same or different lengths. According to claim 1,
wherein the tubes of the first tube group and the tubes of the second tube group have the same diameter. According to claim 1,
wherein the diameters of the tubes of the first tube group are greater than the diameters of the tubes of the second tube group. According to claim 1,
wherein the diameters of the tubes of the second tube group are greater than the diameters of the tubes of the first tube group. According to claim 1,
A bubble-shell-and-tube apparatus comprising a bubble shell-and-tube reactor. 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. According to claim 1,
wherein the reagent supply devices include a liquid phase supply device and a gas phase supply device, and the reaction product withdrawal devices include a liquid phase withdrawal device and a gas phase withdrawal device. A method of carrying out a chemical reaction in a bubble shell-and-tube apparatus according to claim 1:
supplying a liquid phase to fill the entire free volume within the tubular portion of the device;
supplying a gaseous phase to the lower portion of the apparatus so that the gas rises up to the lower tube sheet and enters the tubes of the second tube group so that the tubes of the second tube group act as bubble tubes;
providing movement of liquid upward through the bubble tubes under the influence of gas;
when reaching the top of the device, the gas-liquid mixture is separated;
fetching weather from the device; and
while withdrawing a smaller portion of the liquid phase, a larger portion of the liquid phase begins to move downward under gravity through the tubes of the first tube group acting as circulation tubes; How to carry out a chemical reaction within. delete delete delete delete

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