Air-lift fermenter with cooling, flow guiding and air inlet device

Abstract

An air-lift fermentation tank with cooling flow guide and air inlet device, comprising a tank body, a cooling flow guide device and an air inlet device are arranged in the tank body, the cooling flow guide device comprises a cooling flow guide coil pipe arranged in a flow guide cylinder shape, the air inlet device adopts a gas-liquid cyclone mixer, the cooling flow guide coil pipe, the gas-liquid cyclone mixer and the tank body are coaxially arranged, the gas-liquid cyclone mixer is located below the cooling flow guide coil pipe, the cooling flow guide coil pipe is a single-layer or multi-layer annular pipe, the fermentation liquid entering the tank body can form axial macrocirculation in the tank body along the cooling flow guide coil pipe, and can flow in and out of the cooling flow guide coil pipe, and cooling semi-circular coil pipes are arranged on the outer wall of the tank body. The application has reasonable and compact structure, high efficiency and energy saving, the heat transfer effect of the cooling flow guide coil pipe is strengthened, the gas-liquid cyclone mixer makes the gas-liquid mixture uniform, the up-down and inner-outer circulation is smooth during the whole fermentation process, the air utilization rate is enhanced, the fermentation efficiency is improved, and the application is suitable for large-scale aerobic microbial fermentation.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of bio-chemical production, and relates to a gas-lift fermenter, in particular to a gas-lift fermenter with cooling and air guiding and air inlet device, which is applied to large-scale industrial aerobic fermentation production. BACKGROUND

[0002] The basic principle of the gas-lift fermenter is that sterile air enters the fermenter through an air distributor, so that a density difference is formed between the aeration side and the reflux side, the fermentation broth on the side with a larger gas holdup rises, and the fermentation broth on the side with a smaller gas holdup falls, and the circulation flow is formed by the directional flow of the draft tube arranged along the axis of the tank body, so that the mass transfer mixing is realized. The large amount of fermentation heat generated in the fermentation process needs to be cooled by a cooling device. Common cooling forms include coil pipes, serpentine pipes, and submerged tube bundle heat exchangers. The reasonable arrangement of the air distributor, the cooling device, and the flow guiding device in the gas-lift fermenter has a significant impact on the production efficiency.

[0003] The cooling form of the gas-lift fermenter is different from that of the conventional mechanical stirring tank. The mechanical stirring fermenter usually adopts the forms of the outer tank wall semi-circular disc pipe, heat exchange pipe bundle, and serpentine pipe, while the gas-lift tank generally adopts the form of the outer tank wall semi-circular disc pipe due to the need to arrange the draft tube in the center of the tank body. In this way, there is a problem of insufficient heat exchange area for the fermentation process with a large amount of heat generation.

[0004] Large-scale gas-lift tank fermentation usually needs to adopt a feeding process, and the initial charge coefficient is not high, and the corresponding initial liquid level is not high. At this time, in order to ensure the axial circulation of the fermentation tank, the draft tube is not allowed to be too high to completely separate the inner and outer fermentation broths, which is difficult to overcome, otherwise it will cause the problem of poor circulation inside and outside the draft tube, therefore, the draft tube needs to be increased to open the circulation flow window or arranged in stages to ensure the axial circulation flow in the tank during the whole fermentation process.

[0005] For the air inlet device at the bottom of the large-scale gas-lift fermenter, there are perforated annular pipe distributors, annular jet pipe distributors, and cyclone mixers. The perforated annular pipe distributor has a simple structure, and the gas-liquid mixing effect and the driving circulation effect are limited; the annular jet pipe distributor has a high demand for the pressure head of the air inlet pipeline, and its gas-liquid mixing effect is limited in the case of fluctuation of the fermentation air volume and insufficient air inlet pressure. The gas-liquid cyclone mixer, as a gas-liquid mixing device, replaces the traditional perforated annular pipe or jet device, so that the air enters from the center, is guided by the vortex channel, is sprayed in a spiral flow, and at the same time, the nearby liquid is attracted into it, and after forced mixing with the gas, it is discharged in an emulsified state, which can effectively drive the fermentation broth to circulate inside and outside the draft tube, and improve the mass transfer efficiency.

[0006] According to the investigation, the existing Chinese patent No. CN201621355289.X, a compound air inlet device of an air-lift fermentation tank, comprises a cyclone mixer, a jet pipe distributor and an air inlet flow distribution device, the jet pipe distributor is in the form of a ring, is arranged between the outer wall of the tank body and the flow guide device, is close to the bottom of the tank body, the cyclone mixer is located directly below the flow guide device, the air inlet flow distribution device is arranged outside the tank body and is connected with the total air inlet pipe, the air inlet flow distribution device is provided with two air inlet pipes which are connected with the cyclone mixer and the jet pipe distributor respectively. Although the fermentation tank improves the fermentation efficiency, the cooling is arranged on the outer wall of the tank body, the flow guide device does not have a cooling function, the cooling and the flow guide are separated from each other, the cooling effect of the fermentation tank is not ideal, and the structure needs to be further improved. SUMMARY

[0007] The technical problem to be solved by the present application is to provide an air-lift fermentation tank with a cooling flow guide and an air inlet device, which has a reasonable structure design, is more efficient and energy-saving, has a good gas-liquid mixing effect and a good cooling effect.

[0008] The technical solution adopted by the present application to solve the above technical problem is: an air-lift fermentation tank with a cooling flow guide and an air inlet device, comprising a tank body, characterized in that: a cooling flow guide device and an air inlet device are arranged in the tank body, wherein the cooling flow guide device comprises a cooling flow guide coil pipe arranged in the form of a flow guide cylinder, the air inlet device adopts a gas-liquid cyclone mixer, the cooling flow guide coil pipe and the gas-liquid cyclone mixer are coaxially arranged with the tank body, and the gas-liquid cyclone mixer is located below the cooling flow guide coil pipe, the cooling flow guide coil pipe is an annular pipe arranged in a single layer or multiple layers, the fermentation liquid entering the tank body can form an axial large circulation in the tank body along the cooling flow guide coil pipe, and can flow in and out through the lead gap of the cooling flow guide coil pipe itself, and a cooling semi-circular coil pipe is arranged on the outer wall of the tank body.

[0009] As an improvement, the cooling flow guide device further comprises a plurality of cooling spiral pipes for increasing the cooling effect, and the cooling spiral pipes are uniformly and spacedly arranged between the cooling flow guide coil pipe and the inner wall of the tank body.

[0010] Further, the gas-liquid cyclone mixer comprises an inner shell and an outer shell, wherein the inner shell has a hollow inner ring, an air inlet is arranged on one side of the top or bottom of the inner shell and is located outside the hollow inner ring, two liquid inlets are arranged on the top and bottom of the outer shell respectively, the reflux fermentation liquid in the cooling flow guide coil pipe passes through the hollow inner ring and is sucked into the cyclone mixer from the lower part to enter the circulation again, a plurality of blades are distributed in the form of a circle in the inner shell and the outer shell to form gas flow cyclone channels, and a vortex channel for gas-liquid mixing is formed between the inner shell and the outer shell.

[0011] Furthermore, the liquid inlet of the gas-liquid cyclone mixer is located within the cylindrical diameter of the cooling guide coil, and the liquid outlet is located outside the cooling guide coil. The liquid outlet is arranged horizontally outward along the cyclone direction of the fermentation liquid, or is arranged upward at an angle of 5 to 15 degrees along the cyclone direction of the fermentation liquid.

[0012] Furthermore, the air inlet is arranged at the bottom of the inner shell and connected to the air inlet pipe, and a control valve is provided on the air inlet pipe.

[0013] Furthermore, the cooling spiral tubes are arranged in a single layer, double layer or triple layer, and the circular rings of each layer are arranged concentrically, and the number of groups of cooling spiral tubes is 4, 6, 8 or 12.

[0014] Finally, the spiral direction of the cooling guide coil can be either along the injection direction of the gas-liquid cyclone mixer or against the injection direction of the gas-liquid cyclone mixer.

[0015] Compared with the prior art, the advantages of the present invention are as follows: a cooling guide coil is set in the tank body, which not only plays a cooling role but also plays a role in guiding the fermentation liquid. Moreover, the inside and outside of the cooling guide coil are not completely isolated from each other like the guide tube of the traditional fermentation tank. The fermentation liquid entering the tank body can form a large axial circulation in the tank body along the cooling guide coil, and can also flow in and out through the guide gap of the cooling guide coil itself; a cooling spiral tube group is set between the cooling guide coil and the inner wall of the tank body, which effectively increases the cooling effect; at the same time, the structure of the gas-liquid cyclone mixer is improved, the air inlet is set in a single layer at the bottom of the gas-liquid cyclone mixer, and the middle of the gas-liquid cyclone mixer has a hollow inner ring, so that the fermentation liquid refluxed inside the cooling guide coil passes through the hollow inner ring and is sucked into the cyclone mixer from the bottom and re-enters the circulation. The structural design of the present invention is reasonable and compact, more efficient and energy-saving, and enhances the heat transfer effect of the cooling guide coil. The gas-liquid cyclone mixer makes the gas and liquid mixed evenly, maintains smooth upper and lower and internal and external circulation throughout the fermentation process, enhances air utilization, improves fermentation efficiency, and is suitable for large-scale aerobic microbial fermentation. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 is a schematic structural diagram of embodiment 1 of the present invention;

[0017] Figure 2 is a schematic structural diagram of embodiment 2 of the present invention;

[0018] Figure 3 yes Figure 1 A transverse cross-sectional view of

[0019] Figure 4 yes Figure 2 A transverse cross-sectional view of

[0020] Figure 5 1 is a schematic structural diagram of a gas-liquid cyclone mixer according to the present invention;

[0021] Figure 6 is Figure 5 a top view;

[0022] Figure 7 is a partial fermentation broth flow schematic of the cooling draft tube pitch gap of the present application. DETAILED DESCRIPTION

[0023] The application will be further described in detail below with reference to the accompanying drawings.

[0024] Example 1

[0025] As shown in Figure 1 , 3 , 5, 6, 7, an air-lift type fermenter with cooling draft and air inlet device, comprising a tank body 1, a cooling draft device and an air inlet device are arranged in the tank body 1, and a cooling semi-circular disc pipe 4 is arranged on the outer wall of the tank body 1. The cooling draft device comprises a cooling draft disc pipe 2 arranged in the shape of a draft cylinder, the air inlet device adopts a gas-liquid cyclone mixer 3, the cooling draft disc pipe 2 and the gas-liquid cyclone mixer 3 are coaxially arranged with the tank body 1, and the gas-liquid cyclone mixer 3 is located below the cooling draft disc pipe 2, the cooling draft disc pipe 2 is arranged as a single layer or multiple layers of annular pipes, and the spiral direction of the cooling draft disc pipe 2 can be along the spraying direction of the gas-liquid cyclone mixer 3 or against the spraying direction of the gas-liquid cyclone mixer 3. The inside and outside of the cooling draft disc pipe 2 are not completely isolated as in the traditional draft cylinder of the fermenter, and the gap of the cooling draft disc pipe 2 can still exchange materials. Even in the case of low initial liquid level, the material exchange inside and outside the draft cylinder can still be ensured, and it is not necessary to arrange multiple levels or open a separate material exchange channel to ensure the axial circulation flow of the fermentation broth under the condition of low liquid level as in the traditional draft cylinder. The cooling draft disc 2 is convenient for CIP cleaning process, and is not easy to accumulate materials, and at the same time, it is convenient for maintenance personnel to observe the accumulation and cleaning conditions inside and outside the cooling draft disc pipe. In this way, the fermentation broth entering the tank body 1 can form an axial large circulation in the tank body 1 along the cooling draft disc pipe 2, and can also flow inside and outside the cooling draft disc pipe 2 itself.

[0026] The gas-liquid cyclone mixer 3 comprises an inner shell 3b and an outer shell 3a, wherein the inner shell 3a has a hollow inner ring 33, the air inlet is arranged at the bottom of the inner shell 3b and located outside the hollow inner ring 33, the air inlet is connected with the air inlet pipe 5, and the air inlet pipe 5 is provided with a control valve. The liquid inlet 31 is two, which are arranged at the top and bottom of the outer shell 3a, the liquid inlet 31 is in the cylinder diameter of the cooling guide disc pipe 2, the liquid outlet 32 is arranged horizontally outward along the direction of the fermentation liquid cyclone, or is arranged upwardly inclined by an angle of 5-15° along the direction of the fermentation liquid cyclone, and in this embodiment, the liquid outlet 32 is arranged upwardly inclined, and the liquid outlet 32 is outside the cooling guide disc pipe 2. The backflow fermentation liquid in the cooling guide disc pipe 2 passes through the hollow inner ring 33 and is sucked into the cyclone mixer 3 from the lower part to enter the circulation again. The inner shell 3b and the outer shell 3a are provided with a plurality of blades 34 in a circumferential manner, the airflow cyclone channel 35 is formed in the inner shell 3b, and the vortex channel 36 for mixing gas and liquid is formed between the inner shell 3b and the outer shell 3a. The vortex channel 36 extends and communicates with the airflow cyclone channel 35. The air enters the airflow cyclone channel 35 of the cyclone mixer 2 from the air inlet pipe 5 on one side, and the fermentation liquid enters from the liquid inlet 31. The gas-liquid two-phase is forcedly mixed into emulsion in the vortex channel 36, and then is sprayed and rotated in all directions, and flows upward naturally. The liquid outlet 32 is sprayed upwardly inclined by a certain angle along the clockwise circumferential direction.

[0027] Figure 4 It is expressed that the fermentation liquid can flow circularly upward and downward along the cooling guide disc pipe 2, and can also perform local mass and heat exchange inside and outside the lead gap 20 of the cooling guide disc pipe 2. The fermentation liquid in the inside 21 of the cooling guide disc pipe flows downward, and the fermentation liquid in the outside 22 of the cooling guide disc pipe flows upward.

[0028] The working principle is as follows: after the sterile compressed air is introduced into the gas-liquid cyclone mixer 3 and sprayed after being uniformly mixed with the liquid, the fermentation liquid with air bubbles rotates radially around the central axis of the fermentation tank, and simultaneously, the liquid naturally rises due to its light specific gravity. From the downward view along the central axis of the fermentation tank, the liquid inlet 31 of the gas-liquid cyclone mixer 3 is located in the inside of the cooling guide disc pipe 2, and the liquid outlet 32 of the gas-liquid cyclone mixer 3 is between the cooling guide disc pipe 2 and the inner wall of the tank body 1. The overall flow direction of the fermentation liquid is downward along the inside of the cooling guide disc pipe 2 to enter the gas-liquid cyclone mixer 3, and after being sprayed from the gas-liquid cyclone mixer 3, the fermentation liquid pushes the fermentation liquid to rise along the outside of the cooling guide disc pipe 2, and then the fermentation liquid flows downward along the inside of the cooling guide disc pipe 2 from the upper part of the tank body 1, and then enters the liquid inlet 31 of the gas-liquid cyclone mixer 3 to form a circulation.

[0029] Example 2,

[0030] As Figure 2 , 4As shown, the air-lift fermenter with cooling and air guiding device is different from the embodiment 1 in that the cooling and air guiding device further comprises a plurality of groups of cooling spiral pipes 6 for increasing the cooling effect, the cooling spiral pipes 6 are uniformly and evenly arranged in a ring between the cooling and air guiding coil pipe 2 and the inner wall of the tank body 1; the cooling spiral pipes 6 are arranged in a single layer, double layers or three layers, and the rings of each layer are arranged concentrically, and the number of groups of the cooling spiral pipes 6 can be 4, 6, 8 or 12, and the embodiment is 6.

[0031] The purpose of arranging the cooling spiral pipes 6 is to increase the cooling area, which is especially suitable for large fermenters.

[0032] The above embodiments are only described for the best examples, and should not be understood as limiting the protection scope of the present application. The cyclone mixer is arranged at a position deviated from the center of the bottom of the tank body, the pipe diameter or lead distance of the group of the cooling and air guiding coil pipe and the cooling spiral pipe is changed, or the relative position of the cyclone mixer and the cooling and air guiding coil pipe is slightly deviated, or the cooling and air guiding coil pipe and the outer tank wall cooling semi-coil pipe are used alone for cooling, or the air inlet of the gas-liquid cyclone mixer is adjusted to the upper part, and similar obvious technical effects which are outstanding over the background art can still be obtained, although it is not the best, and it is still the protection scope we require.

Claims

1. An airlift fermenter with a cooling, guiding and air intake device, comprising a tank body, characterized in that: The tank body is provided with a cooling guide device and an air intake device, wherein the cooling guide device includes a cooling guide coil arranged in a guide cylinder shape, the air intake device adopts a gas-liquid cyclone mixer, the cooling guide coil, the gas-liquid cyclone mixer and the tank body are coaxially arranged, and the gas-liquid cyclone mixer is located below the cooling guide coil, the cooling guide coil is a single-layer or multi-layer annular tube, and the fermentation liquid entering the tank body can form an axial large circulation in the tank body along the cooling guide coil, and can also flow in and out through the guide gap of the cooling guide coil itself, and a cooling semicircular coil is arranged on the outer wall of the tank body; The cooling guide device also includes a plurality of cooling spiral tubes for increasing the cooling effect, and the cooling spiral tubes are evenly spaced in the circumferential direction and arranged between the cooling guide coil and the inner wall of the tank body; The gas-liquid cyclone mixer includes an inner shell and an outer shell, wherein the inner shell has a hollow inner ring, an air inlet is arranged on one side at the top or bottom of the inner shell and located on the outside of the hollow inner ring, and there are two liquid inlets, which are respectively arranged at the top and bottom of the outer shell. The fermentation liquid refluxed inside the cooling guide coil passes through the hollow inner ring and is sucked into the gas-liquid cyclone mixer from the bottom and enters the circulation again. A number of blades are distributed circumferentially inside the inner shell and the outer shell, thereby forming an airflow cyclone channel in the inner shell, and a gas-liquid mixing vortex channel is formed between the inner shell and the outer shell, and the vortex channel and the airflow cyclone channel are extended and connected.

2. The airlift fermenter according to claim 1, wherein: The liquid inlet of the gas-liquid cyclone mixer is located within the cylindrical diameter of the cooling guide coil, and the liquid outlet is located outside the cooling guide coil. The liquid outlet is arranged horizontally outward along the cyclone direction of the fermentation liquid, or is arranged upward at an angle of 5 to 15 degrees along the cyclone direction of the fermentation liquid.

3. The airlift fermenter according to claim 2, characterized in that: The air inlet is arranged at the bottom of the inner shell and is connected to the air inlet pipe, and a control valve is provided on the air inlet pipe.

4. The airlift fermenter according to claim 1, wherein: The spiral direction of the cooling guide coil is along the injection direction of the gas-liquid cyclone mixer, or is opposite to the injection direction of the gas-liquid cyclone mixer.

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