Method for sterilizing fermentation system by using waste heat of air compressor

Abstract

The invention discloses a method for sterilizing a fermentation system by using waste heat of an air compressor, and relates to the technical field of fermentation. The fermentation system comprises an air compressor, a first-stage condenser, a primary-efficiency first-stage filter, a second-stage condenser, a primary-efficiency second-stage filter, an air storage tank, a heater, a primary-efficiency third-stage filter, a medium-efficiency filter, a high-efficiency filter and a fermentation tank which are communicated in sequence, and the sterilization step comprises closing the first-stage condenser, the second-stage condenser and the heater; and closing a steam inlet valve of the high-efficiency filter, starting an air compressor, and closing the air compressor after 1-2 hours to finish sterilization. The device is simple in structure, safe and energy-saving, fully utilizes the existing waste heat resource of the air compressor, can realize sterilization without external energy, and saves the cost.

Description

Technical Field

[0001] The invention relates to the technical field of fermentation, and in particular to a method for sterilizing a fermentation system by utilizing waste heat of an air compressor. Background Art

[0002] The air system accounts for more than 50% of fermentation contamination, which is the main factor of fermentation contamination. At present, the sterilization measures in the air mainly rely on air filters. The high-efficiency filters are sterilized by steam, while the front-end primary filters, medium-efficiency filters and air ducts are generally not equipped with sterilization measures. Long-term use without sterilization measures leads to the accumulation of dirt in the primary filters, medium-efficiency filters and air ducts. Miscellaneous bacteria will breed in the accumulation of dirt, thereby increasing the risk of fermentation tank contamination. If a steam pipe is installed in the pipeline after the air compressor, the primary filter, medium-efficiency filter and pipeline behind it are sterilized. It is necessary to open a small exhaust at the lowest point of all equipment to discharge steam condensate. Many equipment are modified and difficult to operate. The use of steam consumes more energy, increases costs, and has poor safety in operation.

[0003] Based on this, we use the waste heat of the air compressor itself to perform heat treatment and sterilization on the equipment between the air compressor and the fermentation tank. It has been verified that the sterilization effect is very good, and the operation is simple and energy-saving, which is very suitable for industrial fermentation production applications. Summary of the invention

[0004] The technical problem to be solved by the present invention is: in view of the deficiencies in the prior art, a method for sterilizing a fermentation system by utilizing waste heat from an air compressor is provided, which has the advantages of simple operation, high safety factor and low cost.

[0005] In order to solve the above technical problems, the technical solution of the present invention is:

[0006] A method for sterilizing a fermentation system using waste heat from an air compressor, wherein the fermentation system comprises an air compressor, a primary condenser, a primary primary filter, a secondary condenser, a primary secondary filter, an air storage tank, a heater, a primary tertiary filter, a medium efficiency filter, a high efficiency filter and a fermentation tank connected in sequence, and the sterilization steps are as follows:

[0007] A: Close the primary condenser, the secondary condenser and the heater, and then close the steam inlet valve of the high efficiency filter;

[0008] B: Turn on the air compressor, and turn it off after 1 to 2 hours, and the sterilization is completed.

[0009] Preferably, when there is no material in the fermentation tank, the air compressor is turned on, and the opening of the second exhaust valve on the top of the fermentation tank is adjusted so that the temperature at the end of the air duct at the outlet of the high-efficiency filter is between 95 and 110° C., and the sterilization is completed.

[0010] Preferably, after turning on the air compressor, the shut-off valve between the high-efficiency filter and the fermentation tank is opened, and the openings of the primary first-stage filter, the primary second-stage filter, the air storage tank, the primary third-stage filter, the medium-efficiency filter, the bottom valve of the high-efficiency filter and the first external exhaust valve between the medium-efficiency filter and the high-efficiency filter are controlled to be 0.5-5%, and then the opening of the second external exhaust valve is adjusted.

[0011] Preferably, the temperature at the end of the air duct at the outlet of the high efficiency filter is maintained at 95-110° C. for 1-2 hours;

[0012] After sterilization, close the primary first-stage filter, the primary second-stage filter, the air storage tank, the primary third-stage filter, the medium-efficiency filter, the bottom valve of the high-efficiency filter, the first exhaust valve, the shut-off valve, the second exhaust valve, and the air compressor.

[0013] Preferably, when there is material in the fermentation tank, the air compressor is turned on, and the opening of the first external exhaust valve between the medium efficiency filter and the high efficiency filter is adjusted so that the temperature at the outlet of the first external exhaust valve is between 95 and 110° C., and sterilization is completed.

[0014] Preferably, the shut-off valve between the high-efficiency filter and the fermentation tank is closed, and the bottom valve openings of the primary first-stage filter, the primary second-stage filter, the air storage tank, the primary third-stage filter, the medium-efficiency filter, and the high-efficiency filter are controlled to be 0.5-5%.

[0015] Preferably, the temperature at the outlet of the first exhaust valve is maintained at 95-110° C. for 1-2 hours;

[0016] After sterilization, close the bottom valves of the primary first-stage filter, the primary second-stage filter, the air storage tank, the primary third-stage filter, the medium efficiency filter, and the high efficiency filter, close the first exhaust valve, and turn off the air compressor.

[0017] Preferably, the filter elements of the primary-level filter, the primary-level filter, the primary-level filter, the medium-efficiency filter and the high-efficiency filter can withstand a temperature of not less than 120°C.

[0018] Due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0019] 1. Basically, there is no need to improve the equipment. Generally, you only need to check the high temperature resistance of the filter element to sterilize the equipment in the air pipeline.

[0020] 2. The operation is simple. You only need to adjust the opening of the first or second external valve, control the temperature by adjusting the air flow, and keep the temperature at the end of the air duct at the outlet of the high-efficiency filter or the outlet of the first external valve at 95-110°C to achieve efficient sterilization.

[0021] 3. Safe and energy-saving, it makes full use of the existing resources of waste heat from the air compressor, and can achieve sterilization without external energy, thus saving costs.

[0022] 4. Safe and environmentally friendly, no need to add other fungicides, environmentally friendly, suitable for industrial fermentation production applications. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0024] Figure 1 is a schematic structural diagram of an embodiment of the present invention;

[0025] Among them: 1. Air compressor; 2. First-stage condenser; 3. Primary-stage filter; 4. Second-stage condenser; 5. Primary-stage filter; 6. Air storage tank; 7. Heater; 8. Primary-stage filter; 9. Medium-efficiency filter; 10. High-efficiency filter; 11. Fermentation tank; 12. Steam inlet valve; 13. Second exhaust valve; 14. Shut-off valve; 15. First exhaust valve. DETAILED DESCRIPTION

[0026] The present invention will be further described below in conjunction with the embodiments.

[0027] Example 1

[0028] A method for sterilizing a fermentation system using waste heat from an air compressor 1, wherein the fermentation system comprises an air compressor 1, a primary condenser 2, a primary primary filter 3, a secondary condenser 4, a primary secondary filter 5, an air storage tank 6, a heater 7, a primary tertiary filter 8, a medium efficiency filter 9, a high efficiency filter 10 and a fermentation tank 11 which are connected in sequence, and the sterilization steps are as follows:

[0029] When there is no material in the fermentation tank 11, the primary condenser 2, the secondary condenser 4 and the heater 7 are closed, and then the steam inlet valve 12 of the high efficiency filter 10 is closed;

[0030] Turn on the air compressor 1, open the shut-off valve 14 between the high-efficiency filter 10 and the fermentation tank 11, control the bottom valve opening of the primary filter 3 to 0.5%, the bottom valve opening of the primary secondary filter 5 to 1%, the bottom valve opening of the air storage tank 6 to 2%, the bottom valve opening of the primary tertiary filter 8 to 3.5%, the bottom valve opening of the medium efficiency filter 9 to 5%, the bottom valve opening of the high-efficiency filter 10 to 2.5%, and the opening of the first external valve 15 between the medium efficiency filter 9 and the high-efficiency filter 10 to 3.5%, adjust the opening of the second external valve 13 at the top of the fermentation tank 11, so that the temperature at the end of the air pipe at the outlet of the high-efficiency filter 10 is maintained at 95-110°C for 1.5 hours, and the sterilization is completed.

[0031] After sterilization, close the primary first-stage filter 3, the primary second-stage filter 5, the air storage tank 6, the primary third-stage filter 8, the medium-efficiency filter 9, the bottom valve of the high-efficiency filter 10, the first external exhaust valve 15, close the cut-off valve 14, close the second external exhaust valve 13, and close the air compressor 1.

[0032] The filter elements of the primary first-stage filter 3, the primary second-stage filter 5, the primary third-stage filter 8, the medium efficiency filter 9 and the high efficiency filter 10 have a temperature tolerance of not less than 120°C.

[0033] Sterile samples of fermentation liquid were taken from the fermenter 11 before and after the air system was sterilized, LB (non-resistant) plates were spread on the clean bench, and the cells were cultured in a 37°C incubator overnight to detect bacterial contamination. If the air system was not sterilized for 2 to 4 weeks, the bacterial contamination rate would increase to 30% to 50% over time. After the air system was sterilized, no bacterial contamination was found in the fermenter 11.

[0034] Example 2

[0035] A method for sterilizing a fermentation system using waste heat from an air compressor 1, wherein the fermentation system comprises an air compressor 1, a primary condenser 2, a primary primary filter 3, a secondary condenser 4, a primary secondary filter 5, an air storage tank 6, a heater 7, a primary tertiary filter 8, a medium efficiency filter 9, a high efficiency filter 10 and a fermentation tank 11 which are connected in sequence, and the sterilization steps are as follows:

[0036] When there is material in the fermentation tank 11, the primary condenser 2, the secondary condenser 4 and the heater 7 are closed, and then the steam inlet valve 12 of the high efficiency filter 10 is closed;

[0037] Turn on the air compressor 1, close the shut-off valve 14 between the high-efficiency filter 10 and the fermentation tank 11, control the bottom valve opening of the primary first-stage filter 3 to 5%, the bottom valve opening of the primary second-stage filter 5 to 0.5%, the bottom valve opening of the air storage tank 6 to 2.5%, the bottom valve opening of the primary third-stage filter 8 to 1.5%, the bottom valve opening of the medium-efficiency filter 9 to 3.5%, and the bottom valve opening of the high-efficiency filter 10 to 4%, adjust the opening of the first external valve 15 between the medium-efficiency filter 9 and the high-efficiency filter 10, and maintain the temperature at the outlet of the first external valve 15 at 95-110°C for 1 hour, and the sterilization is completed.

[0038] After sterilization, close the bottom valves of the primary first-stage filter 3, the primary second-stage filter 5, the air storage tank 6, the primary third-stage filter 8, the medium efficiency filter 9, and the high efficiency filter 10, close the first external exhaust valve 15, and turn off the air compressor 1.

[0039] The filter elements of the primary first-stage filter 3, the primary second-stage filter 5, the primary third-stage filter 8, the medium efficiency filter 9 and the high efficiency filter 10 have a temperature tolerance of not less than 120°C.

[0040] Sterile samples of fermentation liquid were taken from the fermenter 11 before and after the air system was sterilized, LB (non-resistant) plates were spread on the clean bench, and the cells were cultured in a 37°C incubator overnight to detect bacterial contamination. If the air system was not sterilized for 2 to 4 weeks, the bacterial contamination rate would increase to 30% to 50% over time. After the air system was sterilized, no bacterial contamination was found in the fermenter 11.

[0041] It can be seen from the above examples that the sterilization method of the present invention has significant effects, and no bacteria contamination occurs in the fermentation tanks after sterilization, thus meeting the needs of industrial fermentation production.

[0042] It should be understood that these embodiments are only used to illustrate the present invention and are not used to limit the scope of the present invention. In addition, it should be understood that after reading the content taught by the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms also fall within the scope limited by the appended claims of the application.

Claims

1. A method for sterilizing a fermentation system using waste heat from an air compressor, characterized in that: The fermentation system includes an air compressor, a primary condenser, a primary primary filter, a secondary condenser, a primary secondary filter, an air storage tank, a heater, a primary tertiary filter, a medium efficiency filter, a high efficiency filter and a fermentation tank which are connected in sequence, and the sterilization steps are as follows: A: Close the primary condenser, the secondary condenser and the heater, and then close the steam inlet valve of the high efficiency filter; B: Turn on the air compressor, and turn it off after 1 to 2 hours, and the sterilization is completed.

2. A method for sterilizing a fermentation system using waste heat from an air compressor as claimed in claim 1, characterized in that: When there is no material in the fermentation tank, the air compressor is turned on, and the opening of the second exhaust valve on the top of the fermentation tank is adjusted to make the temperature at the end of the air duct at the outlet of the high-efficiency filter between 95 and 110° C., and the sterilization is completed.

3. A method for sterilizing a fermentation system using waste heat from an air compressor as claimed in claim 2, characterized in that: After turning on the air compressor, the shut-off valve between the high-efficiency filter and the fermentation tank is opened, and the openings of the primary first-stage filter, the primary second-stage filter, the air storage tank, the primary third-stage filter, the medium-efficiency filter, the bottom valve of the high-efficiency filter and the first external exhaust valve between the medium-efficiency filter and the high-efficiency filter are controlled to be 0.5-5%, and then the opening of the second external exhaust valve is adjusted.

4. A method for sterilizing a fermentation system using waste heat from an air compressor as claimed in claim 2, characterized in that: Maintain the terminal temperature of the air duct at the outlet of the high efficiency filter at 95-110° C. for 1-2 hours; After sterilization, close the primary first-stage filter, the primary second-stage filter, the air storage tank, the primary third-stage filter, the medium-efficiency filter, the bottom valve of the high-efficiency filter, the first exhaust valve, the shut-off valve, the second exhaust valve, and the air compressor.

5. The method for sterilizing a fermentation system using waste heat from an air compressor as claimed in claim 1, characterized in that: When there is material in the fermentation tank, the air compressor is turned on, and the opening of the first external valve between the medium efficiency filter and the high efficiency filter is adjusted so that the temperature at the outlet of the first external valve is between 95 and 110° C., and the sterilization is completed.

6. A method for sterilizing a fermentation system using waste heat from an air compressor as claimed in claim 5, characterized in that: The cut-off valve between the high-efficiency filter and the fermentation tank is closed, and the bottom valve openings of the primary first-stage filter, the primary second-stage filter, the air storage tank, the primary third-stage filter, the medium-efficiency filter, and the high-efficiency filter are controlled to be 0.5-5%.

7. A method for sterilizing a fermentation system using waste heat from an air compressor as claimed in claim 5, characterized in that: Maintaining the temperature at the outlet of the first exhaust valve at 95-110° C. for 1-2 hours; After sterilization, close the bottom valves of the primary first-stage filter, the primary second-stage filter, the air storage tank, the primary third-stage filter, the medium efficiency filter, and the high efficiency filter, close the first exhaust valve, and turn off the air compressor.

8. The method for sterilizing a fermentation system using waste heat from an air compressor as claimed in claim 1, characterized in that: The filter elements of the primary-level filter, the primary-level filter, the primary-level filter, the medium-level filter and the high-efficiency filter have a temperature tolerance of not less than 120°C.

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