Airlift bioreactor for enhancing mass transfer efficiency

Abstract

The utility model discloses an airlift bioreactor for enhancing mass transfer efficiency, which comprises an outer tower body, an inner cylinder body coaxially arranged with the outer tower body is arranged in the outer tower body, a filler area and an up-flow mixing area which are arranged up and down are arranged in the inner cylinder body, and the filler area and the up-flow mixing area jointly form an up-flow area. A down-flow area is arranged between the outer wall of the inner barrel and the inner wall of the outer tower body; a first aeration plate is mounted above the filler area, a second aeration plate is mounted at the joint of the lower part of the filler area and the upflow mixing area, the first aeration plate and the second aeration plate are both of convex structures with upwards protruded middle parts, and a plurality of through holes are formed in the first aeration plate and the second aeration plate; a propeller plate is fixedly arranged in the up-flow mixing area, and an inclined spiral sieve plate is arranged in the down-flow area. According to the airlift bioreactor provided by the utility model, the fluid passing efficiency at the filler partition plate can be improved, the air blocking phenomenon is avoided, and meanwhile, the problems of high equipment amplification difficulty, low mass transfer efficiency, frequent microbial living environment change, overhigh shearing force and the like are solved.

Description

Technical Field

[0001] The utility model relates to an airlift bioreactor with enhanced mass transfer efficiency, belonging to the technical field of bioreactors. Background Art

[0002] An airlift reactor is a gas-powered reactor. Its original design resembled a bubble column, with material circulated through a defined path. This type of reactor has attracted significant interest in the industry because it provides the necessary aeration and agitation during fermentation with low energy input. Compared to traditional reactors such as stirred tank reactors and bubble columns, airlift reactors offer gentler and more uniform turbulence, making them particularly suitable for various cell culture applications. With advances in the chemical industry and bioengineering, the development of high-efficiency airlift biochemical reactors has received increasing attention. These reactors can improve production efficiency and product quality, making them suitable for high-viscosity and high-density bioculture processes, as well as for large-scale plant and animal cell bioculture. Airlift bioreactors have also found application in animal cell culture. These reactors have shown potential in the production of viral vaccines, monoclonal antibodies, and in vitro meat. Key areas of research include design parameters, transport phenomena during culture, and cell shear sensitivity.

[0003] In recent years, researchers have developed a variety of airlift bioreactors. For example, Zhang Fenfen et al. [[1] Zhang Fenfen, Ma Xiaojian, Fang Shuqi, et al. Optimization of the cultivation process of Chlorella in an internal light source airlift reactor [J]. Chemical Industry Progress, 2018, 37(2):8. DOI:CNKI:SUN:HGJZ.0.2018-02-014.] designed an internal light source airlift photobioreactor for the cultivation of Chlorella. The total volume of the equipment is 50L, and the light source is provided by the built-in lamp column. However, due to the position of the lamp column and the transmittance of the liquid, the light source illumination time needs to be increased during operation, and the algae density needs to be controlled, which also brings high difficulty to industrial scale-up.

[0004] The Chinese utility model patent with publication number CN208500922U discloses a design that uses a honeycomb-shaped device to guide gas. Multiple sets of honeycomb baffles and backflow pipes are used to guide the fluid, thereby increasing the residence time of the gas. However, the honeycomb-shaped gas-liquid mixing tank itself occupies a large volume, which is not conducive to the effective use of space. In addition, the thinner diversion pipes are prone to creating cleaning dead corners, which is not conducive to production.

[0005] Chinese utility model patent publication number CN207928997U discloses an airlift-filled bioreactor for treating organic waste gas. The organic waste gas mixes and rises in the inner cylinder, where it is degraded by suspended microorganisms in the upflow zone and fixed microorganisms on the biofill in the downflow zone. However, due to the solubility and residence time of the gas in water, most of the gas is discharged directly through the outlet after passing through the upflow zone, leaving only a portion of the gas able to pass through the downflow zone. Furthermore, the downflow zone suffers from insufficient power and excessive resistance, which can easily cause large amounts of localized backflow in the inner cylinder during scale-up, leading to failure of the outer cylinder.

[0006] Traditional airlift bioreactors have significant differences in gas holdup between the upflow and downflow zones. Microorganisms uniformly distributed within these zones must navigate rapid transitions between high and low dissolved oxygen environments. Furthermore, the high shear at the gas inlet is detrimental to microbial survival and can easily disrupt microorganisms or microbial colonies. Furthermore, factors such as water pressure and gas dispersion efficiency limit the height and volume of traditional airlift reactors.

[0007] In common packed bioreactors, packing partitions are set at the bottom and top of the packing area, and several small holes are set on them to allow materials to pass through. However, when the small holes are too small or too dense, the surface tension will cause the passage of materials here to be hindered, and even air plugging may occur. When the small holes are too large or too sparse, the partition itself has a weak effect on dispersing the materials, which is likely to produce dead zones and is not conducive to improving production efficiency.

[0008] In summary, the existing technology has obvious inconveniences and defects in actual use, so it is necessary to improve it. Utility Model Content

[0009] In response to the deficiencies in the background technology, the utility model provides an airlift bioreactor with enhanced mass transfer efficiency, which can improve the efficiency of fluid passing through the filler partition and avoid air plugging. At the same time, it solves the problems of high difficulty in equipment scale-up, low mass transfer efficiency, frequent changes in the living environment of microorganisms, and excessive shear force.

[0010] In order to solve the above technical problems, the present invention adopts the following technical solutions:

[0011] An airlift bioreactor for enhancing mass transfer efficiency comprises an outer tower body, an inner cylinder body coaxially arranged therein is mounted inside the outer tower body, a packing area and an upflow mixing area are arranged in the inner cylinder body, the packing area and the upflow mixing area together forming an upflow area, and a downflow area is provided between the outer wall of the inner cylinder body and the inner wall of the outer tower body;

[0012] The packing area is provided with biological packing, a first aeration plate is installed above the packing area, and a second aeration plate is installed below the packing area at the connection with the upflow mixing area. The first aeration plate and the second aeration plate are both convex structures protruding upward in the middle, and are provided with a plurality of through holes.

[0013] A screw blade is fixedly arranged in the upflow mixing zone, and an inclined screw screen plate is arranged in the downflow zone.

[0014] Furthermore, an air inlet is provided at the bottom of the outer tower body, an air inlet aeration head is provided inside the air inlet, and an air outlet is provided at the top of the outer tower body.

[0015] Furthermore, a bell mouth is provided at the lower part of the upflow area of ​​the inner cylinder, the diameter of the bell mouth gradually decreases upward along the air inlet direction, the top diameter is the same as the diameter of the inner cylinder and is connected to the bottom end of the inner cylinder.

[0016] Furthermore, the inclined spiral sieve plate is distributed in a spiral shape as a whole, and a plurality of through holes are provided on the inclined spiral sieve plate, and the inclined spiral sieve plate is fixed on the outer wall of the inner cylinder.

[0017] Furthermore, a three-phase separator is installed on the top of the inner cavity of the outer tower body, and the three-phase separator is located above the inner cylinder and the filling area.

[0018] Furthermore, the bottom of the outer tower body is a conical structure, and a mud discharge trough is provided at the bottom of the conical bottom.

[0019] Furthermore, a top pH probe is installed in the top mixing zone of the outer tower body, and a bottom pH probe is installed in the bottom mixing zone of the outer tower body.

[0020] Furthermore, an acid feed port and an alkali feed port are provided on the top of the outer tower body.

[0021] Furthermore, the propeller blade has a straight blade structure of six blades, eight blades or twelve blades.

[0022] Furthermore, the diameter ratio of the outer tower body to the inner cylinder body is 1.5:1, the height ratio of the inner cylinder body to the outer tower body is 0.6:1, and the height to diameter ratio of the inner cylinder body is 8-12:1.

[0023] Compared with the prior art, the present invention has the following advantages after adopting the above technical solution:

[0024] The utility model fixes microorganisms on biological fillers and places them in an environment with high gas holdup, rich substances and suitable shear force, which can enable the microorganisms to produce at a high level continuously and avoid the decline in production efficiency caused by rapid changes in the environment when the microorganisms flow with the fluid;

[0025] The mixing components installed in the upflow mixing zone and downflow zone can improve material mass transfer, which is conducive to the large-scale equipment;

[0026] The convex structure of the aeration plate is conducive to the rapid passage of fluid, avoiding the air plug phenomenon caused by surface tension. At the same time, it can disperse the strong shear force brought by high-speed airflow and reduce the difficulty of equipment design.

[0027] The present invention will be described in detail below with reference to the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a structural diagram of the present utility model.

[0029] In the figure, 1-inner cylinder, 2-outer tower body, 3-biological filler, 4-inclined spiral sieve plate, 5-first aeration plate, 6-second aeration plate, 7-propeller plate, 8-bell mouth, 9-air inlet aeration head, 10-three-phase separator, 11-top pH probe, 12-bottom pH probe, 13-sludge trough, 14-air inlet, 15-air outlet, 16-acid feed port, 17-alkali feed port. DETAILED DESCRIPTION

[0030] In order to have a clearer understanding of the technical features, purposes and effects of the present invention, the specific implementation methods of the present invention are now described with reference to the accompanying drawings.

[0031] like Figure 1 As shown, the utility model provides an airlift bioreactor with enhanced mass transfer efficiency, comprising an outer tower body 2, inside which is installed an inner cylinder body 1 coaxially arranged therewith, wherein the inner cylinder body 1 comprises a filling area and an upflow mixing area arranged above and below, the filling area and the upflow mixing area together constitute an upflow area, and a downflow area is provided between the outer wall of the inner cylinder body 1 and the inner wall of the outer tower body 2.

[0032] An air inlet 14 is provided at the bottom of the outer tower body 2 , an air inlet aeration head 9 is provided inside the air inlet 14 , and an air outlet 15 is provided at the top of the outer tower body 2 .

[0033] The packing area is provided with biological packing 3, a first aeration plate 5 is installed above the packing area, and a second aeration plate 6 is installed below the packing area at the connection with the upflow mixing area. The first aeration plate 5 and the second aeration plate 6 are both convex structures protruding upward in the middle, and are provided with a plurality of through holes.

[0034] The convex structure makes the pressure at different places of the aeration plate structure different, so that the gas can pass through quickly and avoid the occurrence of gas blockage. At the same time, this structure can improve the efficiency of gas lateral distribution. In addition, the first aeration plate 5 and the second aeration plate 6 can be used as filler partitions.

[0035] A bell mouth 8 is provided at the lower part of the upflow area of ​​the inner cylinder 1. The diameter of the bell mouth 8 gradually decreases upward along the air inlet direction. The top diameter is the same as the diameter of the inner cylinder 1 and is connected to the bottom end of the inner cylinder 1 to ensure that all the gas enters the inner cylinder 1.

[0036] A propeller plate 7 is fixedly mounted in the upflow mixing zone. The propeller plate 7 has six, eight, or twelve straight blades. The propeller plate 7 imparts lateral motion to the rising fluid to promote mass transfer and prevent excessive localized backflow within the large airlift reactor.

[0037] An inclined spiral sieve plate 4 is provided in the downflow area. The inclined spiral sieve plate 4 is distributed in a spiral shape as a whole and has multiple through holes. The inclined spiral sieve plate 4 is fixed on the outer wall of the inner cylinder 1 and can move with the inner cylinder 1.

[0038] The inclined spiral screen plate 4 is provided to promote lateral movement of the material and concentrate large solid particles on the inner wall of the outer tower body 2 due to centrifugal force, preventing solid particles from entering the high shear force area near the air inlet, resulting in small particles being broken and affecting equipment operation. The inclined spiral screen plate 4 is provided with a plurality of through holes to promote longitudinal movement of the material and create turbulence, which promotes material mixing.

[0039] A three-phase separator 10 is installed on the top of the inner cavity of the outer tower body 2. The three-phase separator 10 is located above the inner cylinder 1 and the packing area. The three-phase separator 10 can separate excess gas to prevent the liquid and bubbles generated during the reaction from overflowing.

[0040] The bottom of the outer tower body 2 is a conical structure, and a mud discharge trough 13 is provided at the bottom of the conical bottom. After the equipment has been running for a period of time, the settled sludge can be discharged in time through the mud discharge trough 13.

[0041] The top mixing zone of the outer tower body 2 is equipped with a top pH probe 11, which is located between the three-phase separator 10 and the second aeration plate 6. The bottom mixing zone of the outer tower body 2 is equipped with a bottom pH probe 12, which is located on the side of the air inlet aeration head 9.

[0042] An acid feed port 16 and an alkali feed port 17 are also provided on the top of the outer tower body 2 and are controlled by an automatic online regulating device.

[0043] In the present invention, the diameter ratio of the outer tower body 2 to the inner cylinder body 1 is 1.5:1, the height ratio of the inner cylinder body 1 to the outer tower body 2 is 0.6:1, and the height to diameter ratio of the inner cylinder body 1 is 8-12:1.

[0044] The biological filler 3 in the filler area of ​​the present invention can be selected using existing technology according to the specific microorganism type and reaction characteristics.

[0045] The specific working principle of this utility model:

[0046] In the present utility model, air or other gas enters the outer tower body 2 from the air inlet 14, enters the inner cylinder 1 for mixing, and after gas-liquid mass transfer occurs in the upflow mixing zone, passes through the first aeration plate 5 and enters the packing zone. After being treated by the microorganisms attached to the fixed membrane in the packing zone, it enters the top of the tower from the second aeration plate 6. The excess gas, liquid and solid are separated by the action of the three-phase separator 10, and the remaining substances enter the downflow zone. The substances are fully mixed again in the downflow zone and then enter the upflow mixing zone again.

[0047] The above description is merely an example of the preferred embodiment of the present invention. Any details not described in detail are common knowledge within the art. The scope of protection of the present invention is determined by the claims. Any equivalent modifications based on the technical teachings of the present invention are also within the scope of protection of the present invention.

Claims

1. An airlift bioreactor with enhanced mass transfer efficiency, characterized by: The invention comprises an outer tower body (2), wherein an inner cylinder body (1) is installed inside the outer tower body (2) and is coaxially arranged therewith, wherein a filling area and an upflow mixing area are arranged above and below the inner cylinder body (1), wherein the filling area and the upflow mixing area together constitute an upflow area, and a downflow area is provided between the outer wall of the inner cylinder body (1) and the inner wall of the outer tower body (2); A biological filler (3) is provided in the filler area, a first aeration plate (5) is installed above the filler area, and a second aeration plate (6) is installed below the filler area at the connection with the upflow mixing area. Both the first aeration plate (5) and the second aeration plate (6) are convex structures protruding upward in the middle, and a plurality of through holes are provided thereon. A screw blade (7) is fixedly provided in the upflow mixing zone, and an inclined screw screen plate (4) is provided in the downflow zone.

2. The airlift bioreactor with enhanced mass transfer efficiency according to claim 1, wherein: An air inlet (14) is provided at the bottom of the outer tower body (2), an air inlet aeration head (9) is provided inside the air inlet (14), and an air outlet (15) is provided at the top of the outer tower body (2).

3. The airlift bioreactor with enhanced mass transfer efficiency according to claim 1, wherein: A bell mouth (8) is provided at the lower portion of the upflow region of the inner cylinder (1). The diameter of the bell mouth (8) gradually decreases upward along the air intake direction. The diameter of the bell mouth (8) is the same as the diameter of the inner cylinder (1) and is connected to the bottom end of the inner cylinder (1).

4. The airlift bioreactor with enhanced mass transfer efficiency according to claim 1, wherein: The inclined spiral sieve plate (4) is distributed in a spiral shape as a whole, and a plurality of through holes are provided thereon. The inclined spiral sieve plate (4) is fixed on the outer wall of the inner cylinder (1).

5. The airlift bioreactor with enhanced mass transfer efficiency according to claim 1, wherein: A three-phase separator (10) is installed on the top of the inner cavity of the outer tower body (2), and the three-phase separator (10) is located above the inner cylinder (1) and the filling area.

6. The airlift bioreactor with enhanced mass transfer efficiency according to claim 1, wherein: The bottom of the outer tower body (2) is a conical structure, and a mud discharge trough (13) is provided at the bottom of the conical bottom.

7. The airlift bioreactor with enhanced mass transfer efficiency according to claim 1, wherein: A top pH probe (11) is installed in the top mixing zone of the outer tower body (2), and a bottom pH probe (12) is installed in the bottom mixing zone of the outer tower body (2).

8. The airlift bioreactor with enhanced mass transfer efficiency according to claim 1, wherein: The top of the outer tower body (2) is also provided with an acid liquid feed port (16) and an alkali liquid feed port (17).

9. The airlift bioreactor with enhanced mass transfer efficiency according to claim 1, wherein: The propeller blade (7) has a straight blade structure of six blades, eight blades or twelve blades.

10. The airlift bioreactor with enhanced mass transfer efficiency according to claim 1, wherein: The diameter ratio of the outer tower body (2) to the inner cylinder body (1) is 1.5:1, the height ratio of the inner cylinder body (1) to the outer tower body (2) is 0.6:1, and the height to diameter ratio of the inner cylinder body (1) is 8-12:1.

Images