Foam circulating device of fermentation tank

Abstract

The utility model relates to the technical field of microbial culture, in particular to a foam circulating device of a fermentation tank. According to the specific technical scheme, the fermentation tank foam circulating device comprises a fermentation tank, the tail gas outlet end and the material supplementing end of the fermentation tank are connected with a collecting pipe and a material supplementing pipe respectively, the collecting pipe and the material supplementing pipe are communicated with a foam collecting tank, and the end, stretching into the foam collecting tank, of the material supplementing pipe is close to the bottom of the foam collecting tank. A peristaltic pump is arranged on the material supplementing pipe, a foam sensor and a defoaming mechanism are arranged in the foam collecting tank, and the foam sensor and the defoaming mechanism are controlled by a controller. The utility model solves the problem of low defoaming efficiency of microorganisms in the process of producing rhamnolipid through fermentation in the prior art.

Description

Technical Field

[0001] This utility model relates to the field of microbial culture technology, specifically to a foam circulation device for a fermenter. Background Technology

[0002] Rhamnollipids are a natural polysaccharide with various physiological activities, including anti-oxidation, anti-inflammation, antiviral, antibacterial, and antithrombotic effects. They can also be used as drug carriers and have broad application prospects in the fields of medicine, food, and cosmetics.

[0003] Some microorganisms have the ability to secrete rhamnolipids. Common rhamnolipid-producing microorganisms include Pseudomonas, Klebsiella, Acinetobacter, and Lactobacillus. During fermentation, aeration is usually performed to provide the oxygen needed by the microorganisms. Simultaneously, the fermentation broth is continuously stirred by a stirrer to promote sufficient contact between the microorganisms and oxygen. This increases the gas content in the fermentation broth, thus forming foam. In addition, microorganisms respire during fermentation, producing gases such as carbon dioxide. These gases form bubbles in the fermentation broth, which then coalesce into foam. Foam formation is particularly pronounced during periods of vigorous microbial growth. In current technology, the liquid level in fermenters is generally only about 50%. Therefore, excessive foam can cause significant material spillage, resulting in waste and environmental pollution. Furthermore, foam rising to the top of the tank may leak through the shaft seal, increasing the chance of contamination.

[0004] The foam contains some fermentation broth and microorganisms. Direct discharge of this foam could lead to the loss of beneficial components in the fermentation broth and even affect the stability of the fermentation process. Furthermore, even after defoaming, the liquid still contains certain nutrients and microorganisms. Therefore, returning the defoamed liquid to the fermenter allows it to continue participating in the fermentation process, thereby improving fermentation efficiency and ensuring the continuity and stability of the fermentation process.

[0005] In existing technologies, defoaming or foam control is often achieved through stirring. For example, overflowing foam is first collected in a collection tank, and after a period of settling, or when foam overflows the collection tank, it is then stirred to defoam. However, due to the large amount of foam and its low water content, peristaltic pumps struggle to promptly return the foam to the fermenter. Therefore, frequent stirring is necessary to prevent foam overflow, resulting in low defoaming efficiency. Furthermore, foam reduces the bioavailability of the substrate and the oxygen mass transfer efficiency, which is detrimental to microbial growth, reduces the utilization efficiency of the fermenter, and ultimately weakens rhamnolipid yield and production efficiency. Summary of the Invention

[0006] To address the shortcomings of existing technologies, this invention provides a fermenter foam circulation device, which solves the problem of low defoaming efficiency of microorganisms in the fermentation production of rhamnolipids.

[0007] To achieve the above objectives, this utility model provides the following technical solution:

[0008] This utility model discloses a foam circulation device for a fermenter, including a fermenter. The exhaust gas outlet end and the feeding end of the fermenter are respectively connected to a collection pipe and a feeding pipe. The collection pipe and the feeding pipe are connected to a foam collection tank. One end of the feeding pipe extends into the foam collection tank near its bottom. A peristaltic pump is installed on the feeding pipe. A foam sensor and a defoaming mechanism are installed inside the foam collection tank. The foam sensor and the defoaming mechanism are controlled by a controller.

[0009] Preferably, the foam collection tank includes a tank body, the open end of the tank body is provided with a sealing plug, the sealing plug is provided with a through hole for the feeding pipe, the collection pipe and the defoaming mechanism to pass through, the through hole is provided with a sealing ring that is interference fit with the feeding pipe, the collection pipe and the defoaming mechanism, and an exhaust pipe is also provided through the sealing plug.

[0010] Preferably, a mounting plate that is interference-fitted with the tank body is provided inside the tank body and below the sealing plug. The feeding pipe and the collecting pipe extend into the tank body through the mounting plate. The foam sensor is fixed on the mounting plate, and the sensing head of the foam sensor is located below the mounting plate.

[0011] Preferably, the defoaming mechanism includes a defoaming tube, which is disposed at the bottom of the mounting plate. The bottom of the defoaming tube is provided with a plurality of spray holes. The inlet end of the defoaming tube passes through the top surface of the mounting plate and is connected to a reagent tube. The inlet end of the defoaming tube is interference-fitted with the mounting plate. The reagent tube passes through a through hole, extends out of the tank body, and is connected to a reagent box.

[0012] Preferably, the mounting plate has a rubber ring at its edge, the rubber ring is interference-fitted with the tank body, and the foam sensor is disposed through the middle of the mounting plate.

[0013] Preferably, the portion of the defoaming tube located at the bottom of the mounting plate is annular, the spray holes are located at the bottom of the defoaming tube, on the inward and outward sides, and the sensing head of the foam sensor is separated from the range of the reagent sprayed from the spray holes.

[0014] Preferably, a limiting block is provided at the bottom of the mounting plate, and the defoaming tube is fixed between the two limiting blocks.

[0015] Preferably, a retaining ring is provided inside the tank, below the mounting plate, and one end of the collecting pipe inside the tank extends below the retaining ring.

[0016] Preferably, the side wall of the sealing plug has a notch through which the cable of the foam sensor passes, and a cable retainer is provided in the notch.

[0017] Preferably, the cable retainer includes a retaining sleeve adapted to the notch, the retaining sleeve having a vertical opening for the cable to pass through, and a support ring having a circumferential top of the retaining sleeve, the opening passing through the support ring, and both the retaining sleeve and the support ring being made of rubber.

[0018] This utility model has the following beneficial effects:

[0019] This invention connects a foam collection tank to the exhaust outlet of the fermenter, effectively collecting the foam generated during fermentation. The foam collection tank is equipped with a foam sensor and a defoaming pipe connected to a reagent tank (containing defoaming agent). When foam reaches a certain height, defoaming agent is sprayed through the defoaming pipe to defoam the foam. The liquid formed after defoaming is returned to the fermenter to continue the reaction. Compared to existing technologies that use stirring for defoaming, this invention significantly improves defoaming efficiency. Furthermore, as the defoaming process proceeds, the resulting liquid is transported back into the fermenter, preventing foam overflowing from the fermenter from remaining there for extended periods, thus avoiding impacts on fermentation efficiency, continuity, and stability. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the structure of this utility model;

[0021] Figure 2 for Figure 1 View of the mounting plate from direction AA;

[0022] Figure 3 for Figure 2 A bottom view;

[0023] Figure 4 This is a schematic diagram of the tank.

[0024] Figure 5 This is a schematic diagram of the sealing plug (in which the retaining sleeve partially extends out of the notch);

[0025] In the diagram: 1. Fermentation tank; 2. Collection pipe; 3. Feeding pipe; 4. Foam sensor; 5. Tank body; 6. Sealing plug; 7. Sealing ring; 8. Exhaust pipe; 9. Mounting plate; 10. Defoaming pipe; 11. Reagent pipe; 12. Rubber ring; 13. Limiting block; 14. Retaining ring; 15. Notch; 16. Fixing sleeve; 17. Support ring; 18. Rubber sleeve. Detailed Implementation

[0026] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0027] Unless otherwise specified, the technical means used in the implementation examples are conventional means well known to those skilled in the art.

[0028] refer to Figures 1-5 This utility model discloses a fermenter foam circulation device, including a fermenter 1. The fermenter is based on existing technology, such as the fermenter sold by Bailun Biotechnology Co., Ltd. This utility model only describes the configuration of components on the fermenter relevant to this utility model; it should be understood that other components, such as pH and DO setting ports, are also provided. The exhaust outlet and feed supply end of the fermenter 1 are respectively connected to a collection pipe 2 and a feed supply pipe 3. The collection pipe 2 and feed supply pipe 3 are connected to a foam collection tank. Foam generated during fermentation in the fermenter is discharged to the foam collection tank through the collection pipe. One end of the feed supply pipe 3 extends into the foam collection tank near its bottom. A peristaltic pump is installed on the feed supply pipe 3 to facilitate pumping the liquid formed by the foam into the fermenter to participate in the reaction. A foam sensor 4 and a defoaming mechanism are installed inside the foam collection tank. The foam sensor 4 and the defoaming mechanism are controlled by a controller. When the foam sensor detects foam, the defoaming mechanism sprays in a defoaming agent to defoam. Ethanol can be selected as the defoamer, and *Pseudomonas aeruginosa* can be selected as the fermentation microorganism. It should be noted that the foam sensor is located near the opening of the foam collection tank, and its height is adjustable. It can be manually controlled to trigger an alarm when the foam reaches a designated height in the foam collection tank. Then, the controller activates the defoaming mechanism to spray defoamer for defoaming treatment. When the foam-forming liquid is pumped into the fermenter, both the liquid formed during defoaming and the liquid formed after defoaming with the defoamer are pumped into the fermenter to participate in the reaction, avoiding material loss and thus preventing any impact on fermentation efficiency.

[0029] Furthermore, the foam collection tank includes a tank body 5. In one embodiment, the diameter of the inlet end of the tank body is smaller than the diameter of the tank body. Compared to having the same diameter as the tank body, this facilitates centralized defoaming treatment. Simultaneously, the foam can quickly reach a designated height and be detected. In this embodiment, both the defoaming mechanism and the foam sensor are located within the smaller diameter section of the tank body. A sealing plug 6 is provided at the open end of the tank body 5. The sealing plug 6 has a through hole through which the feeding pipe 3, the collection pipe 2, and the defoaming mechanism pass. A sealing ring 7, which is interference-fitted with the feeding pipe 3, the collection pipe 2, and the defoaming mechanism, is provided within the through hole. An exhaust pipe 8 also passes through the sealing plug 6. It should be noted that the exhaust pipe and sealing plug are configured in the same way as the feeding pipe or the collection pipe, which prevents foam from overflowing from the feeding pipe, the collection pipe, the defoaming mechanism, and the gaps between the exhaust pipe and the sealing plug when the foam can grow too quickly in the tank. Valves can be installed on the feeding pipe, the collection pipe, and the exhaust pipe as needed.

[0030] Furthermore, a mounting plate 9, which is interference-fitted with the tank body 5, is provided inside the tank body 5 below the sealing plug 6. Specifically, a rubber ring 12 is provided on the edge of the mounting plate 9. The rubber ring 12 is interference-fitted with the tank body 5. When fixing the mounting plate inside the tank, the fixing position of the mounting plate can be selected as needed. At the same time, by changing the rubber ring of different widths, the mounting plate can be fixed at different inner diameters inside the tank. The feeding pipe 3 and the collecting pipe 2 extend into the tank body 5 through the mounting plate 9. The feeding pipe and the collecting pipe are gap-fitted with the mounting plate, so that the air inside the tank can pass through the gap and then be discharged through the exhaust pipe. The foam sensor 4 is fixed on the mounting plate 9, and the sensing head of the foam sensor 4 is located below the mounting plate 9. At the same time, the height of the sensing head extending below the mounting plate determines the height of the foam alarm. As one embodiment, the foam sensor 4 is disposed through the middle of the mounting plate 9. Of course, it can also be in other positions, which can be adjusted according to the position and shape of the defoaming mechanism. In order to facilitate the adjustment of the position of the foam sensor, a sealing ring is also provided in the hole through which the foam sensor passes through the mounting plate. The foam sensor and the sealing ring are interference fit, and under the action of external force, the foam sensor can be moved up and down a certain distance within the sealing ring.

[0031] Furthermore, the defoaming mechanism includes a defoaming tube 10, which is disposed at the bottom of the mounting plate 9. The bottom of the defoaming tube 10 has several spray holes. The inlet end of the defoaming tube 10 passes through the top surface of the mounting plate 9 and is connected to a reagent tube 11. The inlet end of the defoaming tube 10 is press-fitted with the mounting plate 9. The reagent tube 11 extends out of the tank 5 through a through hole and is connected to a reagent box. It should be noted that, in one embodiment, the inlet end of the defoaming tube is a straight tube that passes through the mounting plate. More preferably, a rubber sleeve 18 is installed inside the hole in the mounting plate through the straight tube. The straight tube and the rubber sleeve are press-fitted, allowing the straight tube to be directly passed through the rubber sleeve and fixed under external force. The straight tube extends out of the top of the mounting plate and is connected to the reagent tube. The reagent tube extends out of the sealing plug through a sealing ring inside the through hole and is fixed. The reagent tube and the sealing plug are press-fitted to achieve sealing and fixation. To improve the atomization effect of the defoamer when sprayed through the nozzles, the nozzles are funnel-shaped, with their diameter decreasing from the inside to the outside of the defoaming tube. The number and layout of the nozzles are adjusted according to actual needs and the coverage area of ​​the sprayed defoamer within the tank. Simultaneously, the sensing head of the foam sensor 4 is positioned away from the area covered by the sprayed reagent (defoamer), meaning the sprayed defoamer cannot contact the sensing head of the foam sensor 4 to avoid erroneous signals. In one configuration, the nozzles are located at the bottom of the defoaming tube 10, on both the inward and outward sides. "Outward" refers to the direction towards the inner wall of the tank, and "inward" refers to the direction towards the center of the tank. A peristaltic pump can be installed on the reagent tube to pump the defoamer into the defoaming tube for spraying; alternatively, a dedicated reagent pump can be used.

[0032] Furthermore, to expand the coverage area of ​​the defoamer spray and increase defoaming efficiency, the portion of the defoaming tube 10 located at the bottom of the mounting plate 9 is annular, such as circular, square, or irregular, and its two ends are not connected. As one possible arrangement, the defoaming tube is positioned around the foam sensor.

[0033] Furthermore, to further secure the defoaming tube, a limiting block 13 is correspondingly provided at the bottom of the mounting plate 9, with two limiting blocks 13 forming a group, and at least one group is provided as needed. The defoaming tube 10 is fixed between the two limiting blocks 13.

[0034] Furthermore, to prevent the mounting plate from falling into the tank, a retaining ring 14 is provided inside the tank 5, below the mounting plate 9. The retaining ring is fixed to the inner wall of the tank, and its width is set as needed, ensuring that the installation of the various components is not affected. One end of the collecting pipe 2 inside the tank 5 extends below the retaining ring 14, for example, it can extend to the middle of the tank.

[0035] Furthermore, in order to facilitate the fixing of the cable of the foam sensor without affecting the sealing effect of the sealing plug, a notch 15 is provided through the side wall of the sealing plug 6 for the cable of the foam sensor 4 to pass through. The width of the notch is based on the cable passing through. The cable can be squeezed into the notch by squeezing. A cable retainer is provided in the notch 15 to fix and seal the cable and to block the notch.

[0036] Specifically: The cable holder includes a fixing sleeve 16 adapted to the notch 15, with openings at both ends. The gap between the fixing sleeve and the notch is as small as possible, or it can be an interference fit, allowing the fixing sleeve to extend into the notch under external force. The fixing sleeve 16 has a vertical opening for the cable to pass through. The cable is squeezed into the fixing sleeve through the opening. A support ring 17 is provided on the top circumference of the fixing sleeve 16, positioned on top of the sealing plug to prevent the fixing sleeve from falling into the tank through the notch. The opening passes through the support ring 17 and does not affect the cable fixing. Both the fixing sleeve 16 and the support ring 17 are made of rubber. During the cable fixing process, the cable is first inserted into the fixing sleeve, then the opening on the fixing sleeve is rotated to face the inner wall of the notch, and then one end of the fixing sleeve is inserted into the notch and pressed until the support ring is flush with the surface of the sealing plug.

[0037] When using this invention, after the foam sensor and all pipes are installed, the fermenter begins fermentation. Foam generated during fermentation enters the tank. The foam that defoams within the pipes is then discharged into the fermenter. Once the remaining foam reaches a designated height within the tank, the foam sensor sends a signal, pumping defoamer into the defoaming pipe to remove the foam. The defoamed liquid is then pumped into the fermenter via a peristaltic pump and a feeding pipe to participate in the reaction. Throughout the defoaming process, as the foam defoams naturally and is further defoamed by the defoamer, the liquid formed within the tank is promptly transported into the fermenter to participate in the reaction, thus preventing overflowing foam from remaining in the fermenter for extended periods, which could affect fermentation efficiency and the continuity and stability of the fermentation process.

[0038] In the description of this utility model, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0039] The embodiments described above are merely preferred embodiments of the present utility model and are not intended to limit the scope of the present utility model. Various modifications and improvements made to the technical solutions of the present utility model by those skilled in the art without departing from the spirit of the present utility model should fall within the protection scope defined by the claims of the present utility model.

Claims

1. A fermenter foam circulation device, comprising a fermenter (1), characterized in that: The exhaust gas outlet end and the feeding end of the fermentation tank (1) are respectively connected to a collection pipe (2) and a feeding pipe (3). The collection pipe (2) and the feeding pipe (3) are connected to a foam collection tank. One end of the feeding pipe (3) extends into the foam collection tank and is close to its bottom. A peristaltic pump is installed on the feeding pipe (3). A foam sensor (4) and a defoaming mechanism are installed in the foam collection tank. The foam sensor (4) and the defoaming mechanism are controlled by a controller.

2. The fermenter foam circulation device according to claim 1, characterized in that: The foam collection tank includes a tank body (5), and a sealing plug (6) is provided at the open end of the tank body (5). The sealing plug (6) is provided with a through hole for the feeding pipe (3), the collection pipe (2) and the defoaming mechanism to pass through. A sealing ring (7) with interference fit with the feeding pipe (3), the collection pipe (2) and the defoaming mechanism is provided in the through hole. An exhaust pipe (8) is also provided through the sealing plug (6).

3. The fermenter foam circulation device according to claim 2, characterized in that: Inside the tank (5), below the sealing plug (6), there is an installation plate (9) that is interference-fitted with the tank (5). The feeding pipe (3) and the collecting pipe (2) pass through the installation plate (9) and extend into the tank (5). The foam sensor (4) is fixed on the installation plate (9), and the sensing head of the foam sensor (4) is located below the installation plate (9).

4. The fermenter foam circulation device according to claim 3, characterized in that: The defoaming mechanism includes a defoaming tube (10), which is located at the bottom of the mounting plate (9). The bottom of the defoaming tube (10) is provided with several spray holes. The inlet end of the defoaming tube (10) passes through the top surface of the mounting plate (9) and is connected to a reagent tube (11). The inlet end of the defoaming tube (10) is press-fitted with the mounting plate (9). The reagent tube (11) passes through a through hole, extends out of the tank (5), and is connected to a reagent box.

5. A fermenter foam circulation device according to claim 3 or 4, characterized in that: The mounting plate (9) is provided with a rubber ring (12) on its edge. The rubber ring (12) is press-fitted with the tank body (5). The foam sensor (4) is disposed through the middle of the mounting plate (9).

6. A fermenter foam circulation device according to claim 4, characterized in that: The defoaming tube (10) is located at the bottom of the mounting plate (9) in a ring shape. The spray hole is located at the bottom of the defoaming tube (10), on the inward and outward sides. The sensing head of the foam sensor (4) is separated from the range of the reagent sprayed from the spray hole.

7. A fermenter foam circulation device according to claim 6, characterized in that: The bottom of the mounting plate (9) is provided with a limiting block (13), and the defoaming tube (10) is fixed between the two limiting blocks (13).

8. A fermenter foam circulation device according to claim 3, characterized in that: A retaining ring (14) is provided inside the tank (5) and below the mounting plate (9). One end of the collecting pipe (2) inside the tank (5) extends to the bottom of the retaining ring (14).

9. A fermenter foam circulation device according to claim 2, characterized in that: The sealing plug (6) has a notch (15) through which the cable of the foam sensor (4) passes, and a cable retainer is provided in the notch (15).

10. A fermenter foam circulation device according to claim 9, characterized in that: The cable holder includes a fixing sleeve (16) adapted to the notch (15), the fixing sleeve (16) has a vertical opening for the cable to pass through, and a support ring (17) is provided on the top circumference of the fixing sleeve (16), the opening passes through the support ring (17), and both the fixing sleeve (16) and the support ring (17) are made of rubber.

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