A high dissolved oxygen fermentation tank and system

Abstract

The invention discloses a high dissolved oxygen fermentation tank and system, wherein a suction pipe is installed in the fermentation tank, and the suction pipe is located below the material liquid surface; the outlet of the suction pipe passes through the fermentation tank and is connected to a material pump, and the outlet of the material pump is connected to a cooler; an ejector is arranged above the fermentation tank, and the material outlet of the cooler is connected to the ejector, and the ejector outlet is connected to the material liquid in the fermentation tank through a downpipe, and an air filter is connected to the ejector; a guide tube is arranged in the material liquid in the fermentation tank, and the outlet of the downpipe is arranged in the guide tube; an exhaust port is arranged at the upper end of the fermentation tank, and the exhaust port is connected to a cyclone, and the lower end of the cyclone is connected to the inside of the fermentation tank through a reflux pipe. The invention can effectively improve the vacuum degree in the ejector, and has higher heat exchange efficiency and lower manufacturing cost. Compared with a general mechanical ventilation fermentation tank, the dissolved oxygen efficiency is increased by about 1.4 times, and the energy consumption is reduced by about 50%. At the same time, a lot of high-value equipment is removed, and the manufacturing cost is reduced by about 50%.

Description

Technical Field

[0001] The invention belongs to the technical field of biological fermentation, and in particular relates to a high-dissolved oxygen fermentation tank and system. Background Art

[0002] There are many types of existing fermentation tanks, mainly mechanical ventilation fermentation, airlift fermentation tanks, self-priming fermentation tanks, and jet fermentation tanks using the Venturi principle. The existing Venturi jet fermentation tank's injection device uses compressed air as a kinetic energy source, and also uses a pump-driven liquid flow as a kinetic energy source. Some ejectors are installed inside the tank, and some are installed outside. The operation effect of the ejector is not ideal. The mechanical ventilation fermentation tank is the most commonly used fermentation tank at present. The transmission system is installed above the tank body, the stirring shaft and multiple sets of agitators are installed in the tank body, and the cooling pipe is also installed in the tank body. This type of fermentation tank relies on an external air compressor to provide it with air. After the air enters the tank, the air is dispersed by the rotation of the agitator, so that the air is distributed in the feed liquid and mixed with the feed liquid. The oxygen in the air dissolves into the feed liquid, thereby providing oxygen to the microorganisms in the fermentation tank. Take a 5-ton mechanical ventilation fermentation tank as an example: a transmission device is installed on the tank body of the mechanical ventilation fermentation tank, and the installed capacity is generally 7.5KW. According to the ventilation volume of 1:1, the installed power of the matching air compressor is 7.5KW. The total installed capacity is 15KW. If calculated based on the active power of 0.8, the actual power is 12KW. The oxygen-consuming fermentation system is a high-energy-consuming operation. Improving the dissolved oxygen efficiency and saving energy and reducing consumption are issues that need to be solved urgently. Summary of the invention

[0003] The purpose of the present invention is to provide a high dissolved oxygen fermentation tank and system to solve the above problems existing in the prior art.

[0004] In order to achieve the above object, the present invention adopts the following technical solutions:

[0005] On the one hand, the present invention provides a high dissolved oxygen fermentation tank, including a fermentation tank body, a guide tube, a suction pipe, an ejector and a downpipe, wherein the ejector is arranged above the fermentation tank body, the guide tube is arranged in the material liquid in the fermentation tank body, the outlet of the ejector is connected to the downpipe, and the outlet of the downpipe extends into the guide tube; the suction pipe is arranged below the material liquid level in the fermentation tank body, and the outlet of the suction pipe extends to the outside of the fermentation tank body.

[0006] On the other hand, the present invention also provides a high dissolved oxygen fermentation system, including the above-mentioned high dissolved oxygen fermentation tank, and also including a material pump and a cooler, the outlet of the suction pipe passes through the fermentation tank body and is connected to the inlet of the material pump, the outlet of the material pump is connected to the material inlet of the cooler, and the material outlet of the cooler is connected to the inlet of the injector; the injector is connected to an air filter; the upper end of the fermentation tank body is provided with an exhaust port, the exhaust port is connected to a cyclone, and the lower end of the cyclone is connected to the interior of the fermentation tank body through a reflux pipe.

[0007] As a preferred technical solution of the present invention, two material pumps are provided, and the two material pumps are installed in parallel. The two material pumps are respectively a first material pump and a second material pump. The outlet of the suction pipe passes through the fermentation tank body and is respectively connected to the inlet of the first material pump and the inlet of the second material pump. The outlet of the first material pump and the outlet of the second material pump are both connected to the inlet of the cooler.

[0008] As a preferred technical solution of the present invention, the number of the injectors is 1 to 16, and when the number of the injectors is two or more, all the injectors are installed in parallel, the outlet of the cooler is respectively connected to the inlets of all the injectors, the outlet of each injector is connected to the material liquid in the fermentation tank body through a downpipe, and the outlet of each downpipe is arranged in a guide tube.

[0009] As a preferred technical solution of the present invention, the air filter includes a coarse air filter and a fine air filter, the ejector is connected to the fine air filter, and the fine air filter is connected to the outside air through the coarse air filter.

[0010] As a preferred technical solution of the present invention, the suction pipe is an annular structure, and a plurality of feeding holes are provided at the upper end and the lower end of the suction pipe.

[0011] As a preferred technical solution of the present invention, an air outlet is provided at the upper end of the cyclone, and the air outlet is connected to the outside through an air flow meter.

[0012] As a preferred technical solution of the present invention, a feed inlet is arranged at the top of the fermentation tank body, and a discharge port is arranged at the bottom of the fermentation tank body.

[0013] As a preferred technical solution of the present invention, the ejector is connected to a steam inlet.

[0014] As a preferred technical solution of the present invention, the cooler is provided with a coolant inlet and a coolant outlet.

[0015] As a preferred technical solution of the present invention, a cleaning water inlet located outside the fermentation tank body is provided between the suction pipe and the material pump.

[0016] Beneficial effects: The high dissolved oxygen fermentation tank of the present invention installs the ejector on the tank top and at a certain distance from the tank, which can effectively improve the vacuum degree in the ejector. The flow rate of the gas-liquid mixture in the downpipe drives the feed liquid in the fermentation tank body to circulate inside and outside the guide tube, which promotes the uniform dissolved oxygen in the feed liquid and further improves the fermentation effect. There are no baffles and heat exchange tubes in the fermentation tank body, and there is no heat exchange jacket on the outer wall. The various heat generated during the fermentation process is exchanged through the cooler installed behind the material pump as a heat exchanger, which has higher heat exchange efficiency and lower manufacturing cost. Compared with the general mechanical ventilation fermentation tank body, the dissolved oxygen efficiency is increased by about 1.4 times, the energy consumption is reduced by about 50%, and the equipment of the air compression system is removed. The manufacturing cost of the fermentation tank alone can be reduced by about 50%. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a structural schematic diagram of the present invention.

[0018] In the figure: 1. fermentation tank body; 2. feed inlet; 3. exhaust outlet; 4. discharge outlet; 5. ejector; 6. downpipe; 7. suction pipe; 8. guide tube; 9-1. first material pump; 9-2. second material pump; 10. cooler; 11. material inlet; 12. coolant outlet; 13. material outlet; 14. coolant inlet; 15. fine air filter; 16. coarse air filter; 17. cyclone; 18. air flow meter; 19. reflux pipe; 20. material liquid level; 21. steam inlet; 22. cleaning water inlet. DETAILED DESCRIPTION

[0019] The following will be combined with the attached Figure 1 The present invention is explained.

[0020] Embodiment 1:

[0021] like Figure 1As shown, this embodiment provides a high dissolved oxygen fermentation tank and a high dissolved oxygen fermentation system, the high dissolved oxygen fermentation tank comprises a fermentation tank body 1, a guide tube 8, a suction pipe 7, an ejector 5 and a downpipe 6, the ejector 5 is arranged above the fermentation tank body 1, and preferably the distance between the ejector liquid spray port and the top of the fermentation tank body is 0.5 meters to 10 meters, the guide tube 8 is arranged in the material liquid in the fermentation tank body 1, the outlet of the ejector 5 is connected to the downpipe 6, the outlet of the downpipe 6 extends to the guide tube 8, and the gas and liquid in the downpipe 6 are connected to the downpipe 6. The flow rate of the mixture drives the liquid in the fermentation tank body 1 to circulate inside and outside the guide tube 8, so as to make the dissolved oxygen in the liquid uniform; wherein, the guide tube is installed below the suction pipe with the downpipe as the center, and the distance from the suction pipe is 0.2 to 1 meter, and the distance from the lower end of the guide tube to the lower head weld of the fermentation tank body is 0.2 to 1 meter; the suction pipe 7 is arranged below the material liquid level 20 in the fermentation tank body 1, and the height from the liquid level is about 0.1 to 1 meter, and the outlet of the suction pipe 7 extends to the outside of the fermentation tank body 1. Preferably, the suction pipe 7 is arranged as an annular structure matching the inside of the fermentation tank body 1, and the annular centerline diameter of the suction pipe 7 is preferably 0.3 to 0.8 times the inner diameter of the fermentation tank body, and multiple feed holes are arranged at the upper and lower ends of the suction pipe 7, and the material enters the suction pipe 7 through the feed holes.

[0022] The high dissolved oxygen fermentation system of this embodiment includes the high dissolved oxygen fermentation tank described above, and also includes a material pump and a cooler 10. The outlet of the suction pipe 7 passes through the fermentation tank body 1 and is connected to the inlet of the material pump to suck the material inside the fermentation tank body 1 into the material pump. The outlet of the material pump is connected to the material inlet 11 of the cooler 10, and is indirectly contacted with cooling water in the cooler 10 for cooling. The material outlet 13 of the cooler 10 is connected to the inlet of the ejector 5, and the cooled material is input into the ejector 5 to form a high-speed downwardly ejected liquid flow in the ejector 5. , and the negative pressure is generated in the ejector 5, and the ejector 5 outlet is connected to the material liquid in the fermentation tank body 1 through the downpipe 6; the ejector 5 is connected to an air filter, and due to the negative pressure generated in the ejector 5, the outside air is sucked into the ejector 5 after passing through the air filter, and the gas and liquid are fully mixed in the ejector 5 and the downpipe 6; the upper end of the fermentation tank body 1 is provided with an exhaust port 3, and the exhaust port 3 is connected to a cyclone 17, and the lower end of the cyclone 17 is connected to the inside of the fermentation tank body 1 through a reflux pipe 19, and the reflux pipe 19 is inserted below the liquid surface. The inhaled air escapes from the material liquid surface 20 and is discharged from the exhaust port 3. Usually, the fermentation liquid has a certain foaming property, and some bubbles will flow out of the fermentation tank body 1 with the air. The airflow containing bubbles flowing out of the exhaust port 3 enters the cyclone 17, and the bubbles collide with the inner wall of the cyclone 17 under the action of centrifugal force and break, and converge to the bottom with the air flow of the cyclone 17, and flow back to the fermentation tank body from the reflux pipe 19. An air outlet is provided at the upper end of the cyclone 17 , and the air outlet is connected to the outside through an air flow meter 18 , so that air without bubbles can flow from the air outlet of the cyclone 17 through the air flow meter 18 and be discharged.

[0023] It should be further explained in this embodiment that a feed port 2 is provided at the top of the fermentation tank body 1 and a discharge port 4 is provided at the bottom of the fermentation tank body 1 to ensure that the fermentation tank body 1 can be fed and discharged normally.

[0024] It should be further explained in this embodiment that the cooler 10 is provided with a cooling liquid inlet 14 and a cooling liquid outlet 12, and the cooling liquid and the fermentation liquid are in indirect contact in the cooler for heat exchange, thereby taking away the heat generated during the fermentation process.

[0025] What needs to be further explained in this embodiment is that the two material pumps are backup for each other, and valves are provided at the inlet and outlet of the material pump and the cooler 10 for isolation, so that the pump can be placed in a standby state by using steam for local sterilization after the repair is completed. Similarly, once a leak occurs in the cooler 10, it can also be isolated with a valve, and restored to use after local steam sterilization after overhaul. Because the cooler 10 as a heat exchanger is easy to overhaul and has a low failure rate, a heat exchanger is not required. Preferably, the material pump is a high temperature resistant pump, and preferably the material pump is a positive displacement pump.

[0026] For dissolved oxygen efficiency, the inventor has comparative test data for comparison. A comparative test was conducted using a traditional mechanical ventilation fermentation tank. Before the dissolved oxygen reached saturation, the dissolved oxygen concentrations of the water in the two tanks were measured for comparison. The dissolved oxygen rate of the high dissolved oxygen energy-saving fermentation system in this embodiment was 1.5 times faster than that of the mechanical ventilation fermentation when the dissolved oxygen concentration was low. In the absence of microbial oxygen consumption, as the dissolved oxygen concentration increased, they eventually became consistent.

[0027] The energy consumption is described as follows:

[0028] Mechanical ventilation fermentation tanks are the most commonly used fermentation tanks at present. A transmission system is installed on the top of the tank, a stirring shaft and multiple sets of stirrers are installed in the tank, and a cooling pipe is also installed in the tank. This type of fermentation tank relies on an external air compressor to provide air to it. After the air enters the tank, the rotation of the stirrer breaks up the air, so that the air is distributed in the feed liquid and mixed with the feed liquid. The oxygen in the air dissolves into the feed liquid, thereby providing oxygen to the microorganisms in the fermentation tank.

[0029] Take a 5-ton mechanical ventilation fermentation tank as an example: In aerobic fermentation, a transmission device is installed on the tank body of the mechanical ventilation fermentation tank. The installed capacity of a 5-ton mechanical ventilation fermentation tank is generally 7.5KW. According to the ventilation volume of 1:1, the installed power of the matching air compressor is 7.5KW. The total installed capacity is 15KW. If calculated based on the active power of 0.8, the actual power is 12KW. At the same ventilation volume, the installed capacity of the high dissolved oxygen energy-saving fermentation tank is 5.5KW. 5.5 / 12=0.46. So the energy saving mentioned above is 50%.

[0030] From the perspective of the fermentation tank itself, the manufacturing cost of the shell only accounts for 40% of the total cost, and the manufacturing cost of the transmission part, stirring part, and cooling part accounts for 60%. The high dissolved oxygen energy-saving fermentation tank has the same shell part, without the transmission part, stirring part, and cooling part, and adds an ejector, downpipe, and guide tube. These parts are empty shells, and the manufacturing cost accounts for up to 10%. Therefore, it can save 50% of the manufacturing cost. Moreover, compared with the existing fermentation system, the present invention omits the air compression system, and the system cost is lower, thereby making the overall cost lower.

[0031] Embodiment 2:

[0032] This embodiment is a further improvement made on the basis of the first embodiment. The specific differences between this embodiment and the first embodiment are:

[0033] It should be further explained in this embodiment that two material pumps are provided, namely the first material pump 9-1 and the second material pump 9-2. The outlet of the suction pipe 7 passes through the fermentation tank body 1 and is connected to the inlet of the first material pump 9-1 and the inlet of the second material pump 9-2 respectively. The outlet of the first material pump 9-1 and the outlet of the second material pump 9-2 are both connected to the inlet of the cooler 10. The first material pump 9-1 and the second material pump 9-2 are pumps with the same performance, which are installed in parallel. Two pumps with the same performance are equipped as backup for each other. Once one of them fails, the other one is started immediately, and the damaged pump is repaired in time. The speed of the material pump can be adjusted to adjust the air volume required by the fermentation tank.

[0034] Embodiment three:

[0035] This embodiment is a further improvement made on the basis of the first or second embodiment. The specific differences between this embodiment and the first or second embodiment are:

[0036] It should be further explained in this embodiment that the number of the injectors 5 is 1 to 16, and when the number of the injectors 5 is two or more, all the injectors 5 are installed in parallel, the outlet of the cooler 10 is connected to the inlet of all the injectors 5 respectively, and the outlet of each injector 5 is connected to the material liquid in the fermentation tank body 1 through the downpipe 6, and the outlet of each downpipe 6 is arranged in a guide tube 8. The specific number of injectors is determined according to the size of the diameter of the fermentation tank shell. The main purpose is to make the material liquid circulation in the tank body more uniform and make the dissolved oxygen in the material liquid more uniform. It should be explained that when multiple groups of injectors are installed, the middle part of the downpipe is bent to ensure installation requirements.

[0037] Embodiment 4:

[0038] This embodiment is a further improvement made on the basis of any one of Embodiments 1 to 3. The specific differences between this embodiment and any one of Embodiments 1 to 3 are:

[0039] It should be further explained in this embodiment that the air filter includes a coarse air filter 16 and a fine air filter 15, the ejector 5 is connected to the fine air filter 15, and the fine air filter 15 is connected to the external air through the coarse air filter 16 to obtain sterile air.

[0040] Embodiment five:

[0041] This embodiment is a further improvement made on the basis of any one of the embodiments 1 to 4. The specific differences between this embodiment and any one of the embodiments 1 to 4 are:

[0042] It should be further explained in this embodiment that the ejector 5 is connected to a steam inlet 21 , more precisely, the steam inlet 21 is arranged on a pipeline between the ejector 5 and the cooler 10 , and is arranged close to the ejector 5 .

[0043] Embodiment six:

[0044] This embodiment is a further improvement made on the basis of any one of the embodiments 1 to 5. The specific differences between this embodiment and any one of the embodiments 1 to 5 are:

[0045] It should be further explained in this embodiment that a cleaning water inlet 22 located outside the fermentation tank body 1 is provided between the suction pipe 7 and the material pump. More precisely, the cleaning water inlet 22 is provided on the connecting pipe between the suction pipe 7 and the material pump. The valve of the cleaning water inlet 22 is opened. If there are more than one material pumps, they are started separately to clean the pipes and heat exchanger. The manhole of the fermentation tank is opened (not shown in the figure) to clean the inner wall of the fermentation tank. Then, steam is passed from the steam inlet 21 to the fermentation tank body for several minutes to complete the repair work.

[0046] The complete working principle of the present invention is as follows:

[0047] 1. Before feeding, sterilize the empty tanks. Steam with pressure that meets the process requirements is introduced from the steam inlet 21 on the upper part of the ejector to achieve sterilization without dead angles. The empty tank sterilization time required by the production process is carried out. After sterilization, a small air compressor with a sterile air purifier at the outlet is used to ventilate the fermentation tank body. The vent is not drawn in the figure to maintain positive pressure in the tank.

[0048] 2. Feed liquid into the fermentation tank body from the feed port 2, close the valve of the air inlet of the ejector 5, and adjust the valve after the exhaust port 3 to maintain the positive pressure in the tank.

[0049] 3. When the feeding is completed, the can is sterilized. Steam is introduced from the steam inlet 21 on the upper part of the ejector according to the steam pressure required by the production process. The steam contacts the liquid through the downpipe 6 and, driven by the kinetic energy of the steam, the liquid circulates in the tank to promote uniform heating of the liquid. Due to the strong dissolution of steam and water, there will be greater noise and vibration when the liquid temperature is low. As the liquid temperature rises, the noise and vibration will gradually decrease until they disappear.

[0050] 4. When the temperature reaches the production process requirements, keep it warm for the time required by the process. When the required insulation time is reached, start the material pump to start pumping liquid circulation, adjust the speed of the material pump, and properly open the valve of the ejector air inlet to maintain the positive pressure in the tank. Because the temperature is high in the early stage, when more than one material pump is installed, they can be used in rotation. Open the cooling water inlet and outlet valves of the cooler to cool the material liquid.

[0051] 5. When the temperature of the feed liquid reaches the inoculation temperature, appropriately reduce the speed of the material pump and maintain a certain positive pressure to inoculate the fermentation tank body.

[0052] 6. After the inoculation is completed, the speed of the material pump is adjusted to adjust the air volume according to the dissolved oxygen required by the process. Unlike other fermentation tanks, the fermentation tank of the present invention is recommended to maintain a tank pressure of about 0.02Mpa. Some types of fermentation tanks require a certain tank pressure to improve the dissolved oxygen efficiency. The fermentation tank of the present invention improves the dissolved oxygen efficiency through the strong mixing action of the injection device, so it only needs to maintain a certain positive pressure in the tank.

[0053] 7. The tank pressure is adjusted by adjusting the valve behind the exhaust port 3, and the air volume is adjusted by adjusting the speed of the pump to achieve the dissolved oxygen conditions required by the process until the fermentation is completed. Since the fermentation tank of the present invention has a high dissolved oxygen efficiency, the air volume is smaller than that of a general fermentation tank.

[0054] 8. After fermentation is completed, it is recommended to use the compressed air in step 1 to discharge the material.

[0055] 9. Open the valve of the cleaning water inlet 22, start the material pump, if there are more than one, start them separately, and clean the pipes and heat exchangers. Open the manhole of the fermenter (not shown in the figure) and clean the inner wall of the fermenter body. Then, pass steam into the fermenter body from the steam inlet 21 for several minutes to complete the repair work.

[0056] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the protection scope of the present invention. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A high dissolved oxygen fermentation tank, characterized in that: The invention comprises a fermentation tank body (1), a flow guide tube (8), a material suction pipe (7), an ejector (5) and a downpipe (6), wherein the ejector (5) is arranged above the fermentation tank body (1), the flow guide tube (8) is arranged in the material liquid in the fermentation tank body (1), the outlet of the ejector (5) is connected to the downpipe (6), and the outlet of the downpipe (6) extends into the flow guide tube (8); the material suction pipe (7) is arranged below the material liquid level (20) in the fermentation tank body (1), and the outlet of the material suction pipe (7) extends to the outside of the fermentation tank body (1).

2. A high dissolved oxygen fermentation system, characterized in that: The invention comprises the high dissolved oxygen fermentation tank as claimed in claim 1, and further comprises a material pump and a cooler (10), wherein the outlet of the suction pipe (7) passes through the fermentation tank body (1) and is connected to the inlet of the material pump, the outlet of the material pump is connected to the material inlet (11) of the cooler (10), and the material outlet (13) of the cooler (10) is connected to the inlet of the ejector (5); the ejector (5) is connected to an air filter; the upper end of the fermentation tank body (1) is provided with an exhaust port (3), the exhaust port (3) is connected to a cyclone (17), and the lower end of the cyclone (17) is connected to the inside of the fermentation tank body (1) through a reflux pipe (19).

3. A high dissolved oxygen fermentation system according to claim 2, characterized in that: Two material pumps are provided, the two material pumps being a first material pump (9-1) and a second material pump (9-2). The outlet of the material suction pipe (7) passes through the fermentation tank body (1) and is respectively connected to the inlet of the first material pump (9-1) and the inlet of the second material pump (9-2). The outlet of the first material pump (9-1) and the outlet of the second material pump (9-2) are both connected to the inlet of the cooler (10).

4. A high dissolved oxygen fermentation system according to claim 2, characterized in that: The number of the injectors (5) ranges from 1 to 16, and when the number of the injectors (5) is two or more, all the injectors (5) are installed in parallel, the outlet of the cooler (10) is respectively connected to the inlets of all the injectors (5), the outlet of each injector (5) is connected to the material liquid in the fermentation tank body (1) through a downpipe (6), and the outlet of each downpipe (6) is arranged in a guide tube (8).

5. A high dissolved oxygen fermentation system according to claim 2 or 3, characterized in that: The air filter comprises a coarse air filter (16) and a fine air filter (15); the ejector (5) is connected to the fine air filter (15); and the fine air filter (15) is connected to external air via the coarse air filter (16).

6. A high dissolved oxygen fermentation system according to claim 2, characterized in that: The suction pipe (7) is an annular structure, and a plurality of feeding holes are provided at the upper end and the lower end of the suction pipe (7).

7. A high dissolved oxygen fermentation system according to claim 2, characterized in that: An air outlet is provided at the upper end of the cyclone (17), and the air outlet is connected to the outside through an air flow meter (18).

8. A high dissolved oxygen fermentation system according to claim 2, characterized in that: The top of the fermentation tank body (1) is provided with a feed inlet (2), and the bottom of the fermentation tank body (1) is provided with a feed outlet (4); the cooler (10) is provided with a cooling liquid inlet (14) and a cooling liquid outlet (12).

9. A high dissolved oxygen fermentation system according to claim 2, characterized in that: The ejector (5) is connected to a steam inlet (21).

10. A high dissolved oxygen fermentation system according to claim 2, characterized in that: A cleaning water inlet (22) located outside the fermentation tank body (1) is provided between the suction pipe (7) and the material pump.

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