External spraying closed circulating type gas fermentation reactor

Abstract

The utility model discloses an external spraying closed circulating type gas fermentation reactor. The reactor comprises a fermentation reaction cavity filled with fermentation liquor, a gas distributor fixedly mounted in the fermentation reaction cavity, three groups of gas supply components used for communicating the gas distributor with corresponding gas sources, a safety valve fixedly mounted at the top of the fermentation reaction cavity, and a spray tower positioned on the corresponding side of the fermentation reaction cavity, the overflow pipe is used for communicating the fermentation reaction cavity with the spray tower, the liquid guide pipe I is used for communicating the circulating pump with the spray tower, and the liquid guide pipe II is used for communicating the circulating pump with the fermentation reaction cavity. According to the utility model, an external spraying closed circulation type gas fermentation system is established, liquid-state and gas-state double-circulation fermentation is realized, no tail gas emission is generated in the whole fermentation process, and the utilization rate of gas is close to 100%.

Description

Technical Field

[0001] The utility model relates to the technical field of gas fermentation, in particular to an externally sprayed closed-circuit gas fermentation reactor. Background Art

[0002] Industries such as coal chemical industry, iron and steel industry, and coal-fired power plants emit hundreds of millions of tons of greenhouse gases every year. Under the current background of carbon emission control, the process technologies of using microbial fermentation to fix carbon dioxide and carbon monoxide have made great progress.

[0003] However, conventional fermentation reactors are designed for liquid fermentation and solid fermentation. When used for gas fermentation, there are disadvantages such as low mass transfer efficiency, short contact time, and low gas utilization rate. At the same time, a large amount of fermentation tail gas will be generated, resulting in secondary pollution. The disclosed reactors for gas fermentation, in order to increase the gas residence time, have complex internal components, which have a negative impact on aseptic control. At the same time, there are still inevitably a large amount of unutilized fermentation tail gas. Summary of the Utility Model

[0004] In view of the above-mentioned disadvantages of the prior art, the purpose of the utility model is to provide an externally sprayed closed-circuit gas fermentation reactor to achieve liquid-gas double-circuit fermentation and achieve a gas utilization rate close to 100%.

[0005] An externally sprayed closed-circuit gas fermentation reactor includes a fermentation reaction cavity filled with fermentation broth; the reactor further includes:

[0006] A gas distributor fixedly installed in the fermentation reaction cavity;

[0007] A gas supply assembly for connecting a gas source and the gas distributor;

[0008] A spray tower located at a corresponding position on one side of the fermentation reaction cavity;

[0009] An overflow pipe for connecting the fermentation reaction cavity and the spray tower;

[0010] A circulation pump;

[0011] A liquid guide pipe I for connecting the circulation pump and the spray tower; and

[0012] A liquid guide pipe II for connecting the circulation pump and the fermentation reaction cavity.

[0013] In one embodiment, the gas distributor is located near the bottom of the cavity, and the gas distributor adopts a loop flow type, a bubbling type or a jet type structure.

[0014] In one embodiment, the type of the gas source is one, and the number of the gas supply assemblies is one group; or, the types of the gas sources are multiple, and the number of the gas supply assemblies is the same as the number of the types of the gas sources.

[0015] Further, the gas supply assembly includes a filter, an inlet pipe I fixedly connected to the inlet of the filter, an inlet pipe II fixedly connected between the filter and the gas distributor, a switch valve and a regulating valve installed on the inlet pipe II.

[0016] Still further, the filter is located at the corresponding other side position of the fermentation reaction cavity, and a filter element is filled in the filter.

[0017] Even further, the inlet pipe II is fixedly arranged through a side wall of the fermentation reaction cavity; the switch valve and the regulating valve are located outside the fermentation reaction cavity, and the switch valve is arranged close to the filter.

[0018] In one embodiment, a liquid distributor is arranged in the spray tower.

[0019] In one embodiment, the circulation pump is located outside the fermentation reaction cavity, and the circulation pump adopts a diaphragm pump or a jet pump.

[0020] Further, the liquid outlet end of the liquid guide pipe II is fixedly connected and penetrated at the bottom of the fermentation reaction cavity.

[0021] In one embodiment, the reactor further includes a safety valve fixedly installed at the top of the fermentation reaction cavity.

[0022] Compared with the prior art, the beneficial effects of the present utility model are as follows: an external spray closed-circuit gas fermentation system is established, realizing liquid-gas double-cycle fermentation. No tail gas is emitted during the whole fermentation process, and the utilization rate of the gas can reach nearly 100%. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 The figure shows a schematic structural diagram of an external spray closed-circuit gas fermentation reactor provided by the present utility model.

[0024] MAIN ELEMENT SYMBOL DESCRIPTION

[0025] 1. Fermentation reaction cavity; 2. Gas distributor; 3. Filter; 4. Inlet pipe I; 5. Inlet pipe II; 6. Switch valve; 7. Regulating valve; 8. Safety valve; 9. Spray tower; 10. Overflow pipe; 11. Liquid guide pipe I; 12. Liquid guide pipe II; 13. Circulation pump.

[0026] The above main element symbol description further describes the present utility model in detail in conjunction with the drawings and the specific embodiments. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0027] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0028] Please refer to Figure 1 , this embodiment provides an external spray closed-circuit gas fermentation reactor, which includes a fermentation reaction cavity 1 filled with fermentation broth, a gas distributor 2 fixedly installed in the fermentation reaction cavity 1, three gas supply components for connecting the gas distributor 2 and the corresponding gas source, a safety valve 8 fixedly installed at the top of the fermentation reaction cavity 1, a spray tower 9 located at a corresponding side position of the fermentation reaction cavity 1, an overflow pipe 10 for connecting the fermentation reaction cavity 1 and the spray tower 9, a circulation pump 13, a liquid guide pipe I 11 for connecting the circulation pump 13 and the spray tower 9, and a liquid guide pipe II 12 for connecting the circulation pump 13 and the fermentation reaction cavity 1.

[0029] In this embodiment, microbial strains are inoculated into the liquid medium. After a period of cultivation, the liquid produced by the microorganisms metabolizing the nutrients in the medium is called fermentation broth. The fermentation broth is rich in microorganisms that dominate the gas fermentation reaction. Through microbial fermentation, the purpose of fixing and utilizing CO2 is achieved, thereby providing support for the treatment of greenhouse gases. Under the background of controlling carbon emissions, it is conducive to popularization and use in industries such as coal chemical industry, iron and steel industry, and coal-fired power plants. It should be noted that the fermentation reaction cavity 1 of this embodiment is also provided with accessories such as a temperature transmitter, internal and external coil pipes, a feed port, a sampling port, and a sight glass that should be available in a conventional fermentation system. The foregoing accessory diagrams are not shown and will not be elaborated.

[0030] The gas distributor 2 is located near the bottom of the cavity, and the gas distributor 2 adopts a bubbling structure. In this embodiment, the gas distributor 2 is provided to drive the fermentation broth to play a stirring role. When the reaction gas is filled into the fermentation broth through the gas distributor 2, a large number of tiny bubbles are introduced, thereby increasing the gas-liquid contact area. At the same time, the gas flow rate through the gas distributor 2 is increased, driving the surrounding fermentation broth to move to generate a stirring effect, and carrying the liquid to gradually rise, so that the gas and microorganisms are fully mixed, improving the conversion rate of microbial fermentation to treat gas, and overcoming the problem of damage to microbial cells existing in traditional mechanical stirring using stirring fan blades.

[0031] The three gas supply components are used to respectively feed CO2, H2 and CO into the fermentation reaction chamber 1. This embodiment uses CO2, H2 and CO as gas sources as an example to illustrate the microbial fermentation reaction: CO2 is used as a carbon source, and the microorganisms convert it into cell substances to participate in the fermentation process. H2 and CO are used as energy sources, and the microorganisms use H2 to reduce CO2 to organic matter, and CO is converted into useful chemicals such as butene through microbial fermentation.

[0032] The air supply assembly includes a filter 3, an air intake pipe I4 fixedly connected to the air inlet of the filter 3, an air intake pipe II5 fixedly connected between the filter 3 and the gas distributor 2, and a switch valve 6 and a regulating valve 7 installed on the air intake pipe II5. The filter 3 is located at the other side of the fermentation reaction chamber 1, and a filter element is filled in the filter 3. In this embodiment, in order to ensure the sterility of the gas entering the fermentation reaction chamber 1, the gas is filtered by the filter 3 while being input to remove impurities such as microorganisms, moisture and dust carried in the gas.

[0033] The air inlet pipe II5 is fixedly arranged through one side wall of the fermentation reaction chamber 1. The switch valve 6 and the regulating valve 7 are located outside the fermentation reaction chamber 1, and the switch valve 6 is arranged close to the filter 3. In this embodiment, during the fermentation process, the switch valve 6 remains normally open, and the regulating valve 7 is set to the pressure required by the process. As the residual gas in the fermentation reaction chamber 1 and the spray tower 11 is gradually consumed, the system pressure decreases, and the regulating valve 7 automatically opens to replenish fresh gas after reaching the set pressure. The switch valve 6 is controlled by a gas online monitoring control switch (not shown) arranged at the top of the fermentation reaction chamber 1, thereby ensuring that the required gas is replenished to the system at any time.

[0034] In this embodiment, the safety valve 8 is in a normally closed state. When the medium pressure in the reactor rises to exceed a threshold value, the safety valve 8 opens to discharge gas to achieve the purpose of pressure relief. It should be noted that in order to prevent the safety valve 8 from directly contacting the fermentation liquid, a bursting disc with a smooth arc surface (not shown) is installed at the position where the safety valve 8 contacts the fermentation liquid, thereby improving the reliability of the safety valve 8.

[0035] In this embodiment, the surface of the fermentation liquid in the fermentation reaction chamber 1 is maintained below the overflow pipe 10. With the continuous replenishment of gas, the gas and the fermentation liquid are mixed and move from bottom to top in the fermentation reaction chamber 1, and the liquid level rises. When the liquid level is higher than the overflow pipe 10, the foam generated by the microbial fermentation flows along the overflow pipe 10 into the spray tower 9 for gas-liquid separation. A liquid distributor is arranged in the spray tower 9. In this embodiment, the liquid distributor is used to prevent the fermentation liquid from gathering into strands or flowing down along the wall when falling in the spray tower 9, thereby reducing the risk of bacterial contamination.

[0036] The circulation pump 13 is located outside the fermentation reaction cavity 1, and the liquid outlet end of the liquid guide pipe II 12 is fixedly connected through the bottom of the fermentation reaction cavity 1. In this embodiment, the circulation pump 13 is provided to effectively mix the fermentation liquid and gas together and then pump them back into the fermentation reaction cavity 1 to continue participating in the microbial fermentation reaction. In this embodiment, a diaphragm pump is taken as an example of the circulation pump 13 for illustration. In other embodiments, the circulation pump 13 can also adopt a jet pump. It should be noted that when a jet pump is adopted, a branch pipe needs to be provided in the air supply assembly, and air is drawn through this branch pipe to provide the air source required when the jet pump works. The purpose of setting the branch pipe is to ensure that no other gases are introduced, and the reaction gas is always passed through in the fermentation reaction cavity 1.

[0037] In this embodiment, a spray tower 9 is provided and cooperates with the circulation pump 13 to achieve efficient mass transfer of gas-liquid two-phase, so as to realize liquid-gas double-cycle fermentation.

[0038] The reactor of this embodiment has established an external spray closed-circuit gas fermentation system, and the specific working process is as follows:

[0039] The air supply assembly sends gas into the fermentation reaction cavity 1, and the gas and the fermentation liquid are mixed and react under the action of microorganisms to be converted into useful chemical substances;

[0040] With the continuous replenishment of gas and the progress of the reaction, the gas and the fermentation liquid are mixed and move from bottom to top, causing the liquid level to rise. At this time, the foam generated by microbial fermentation enters the spray tower 9 along the overflow pipe 10 for gas-liquid separation;

[0041] Then, the circulation pump 13 is started, so that the liquid and part of the gas mixture after passing through the spray tower 9 are pumped back into the fermentation reaction cavity 1 to continue participating in the reaction, thereby realizing liquid-gas double-cycle fermentation.

[0042] In summary, the reactor of this embodiment has the following advantages: it has established an external spray closed-circuit gas fermentation system, realizes liquid-gas double-cycle fermentation, does not generate any tail gas emissions during the whole fermentation process, can use nearly 100% of the gas for microbial fermentation, solves the problems of low mass transfer efficiency and low gas utilization rate in the gas fermentation process of conventional fermenters, and fundamentally solves the problem of tail gas emissions.

[0043] The above-described embodiments only represent several implementation manners of the present invention, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the utility model patent. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several modifications and improvements can still be made, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the utility model patent shall be subject to the appended claims.

Claims

1. An external spraying closed circulation gas fermentation reactor, comprising a fermentation reaction chamber (1) containing a fermentation liquid; It is characterized in that The reactor further comprises: A gas distributor (2) fixedly installed in the fermentation reaction chamber (1); A gas supply assembly, used to connect the gas source and the gas distributor (2); A spray tower (9), which is located at a position on a side corresponding to the fermentation reaction chamber (1); An overflow pipe (10) for connecting the fermentation reaction chamber (1) and the spray tower (9); Circulation pump (13); a liquid conduit I (11) for connecting the circulation pump (13) and the spray tower (9); and A liquid conduit II (12) for connecting the circulation pump (13) and the fermentation reaction chamber (1).

2. The external spraying closed circulation gas fermentation reactor according to claim 1, characterized in that: The gas distributor (2) is located near the bottom of the cavity, and the gas distributor (2) adopts a circulation type, bubbling type or jet type structure.

3. The external spraying closed circulation gas fermentation reactor according to claim 1, characterized in that: The type of gas source is one, and the number of gas supply components is one group; Alternatively, there are multiple types of gas sources, and the number of gas supply components is consistent with the number of gas source types.

4. The external spraying closed circulation gas fermentation reactor according to claim 3, characterized in that: The gas supply assembly comprises a filter (3), an air intake pipe I (4) fixedly connected to the air intake port of the filter (3), an air intake pipe II (5) fixedly connected between the filter (3) and the gas distributor (2), and a switch valve (6) and a regulating valve (7) mounted on the air intake pipe II (5).

5. The external spraying closed circulation gas fermentation reactor according to claim 4, characterized in that: The filter (3) is located at a position corresponding to the other side of the fermentation reaction chamber (1), and a filter element is filled in the filter (3).

6. The external spraying closed circulation gas fermentation reactor according to claim 5, characterized in that: The air inlet pipe II (5) is fixedly arranged through a side wall of the fermentation reaction chamber (1); The switch valve (6) and the regulating valve (7) are located outside the fermentation reaction chamber (1), and the switch valve (6) is arranged close to the filter (3).

7. The external spraying closed circulation gas fermentation reactor according to claim 1, characterized in that: The spray tower (9) is provided with a liquid distributor.

8. The external spraying closed circulation gas fermentation reactor according to claim 1, characterized in that: The circulation pump (13) is located outside the fermentation reaction chamber (1), and the circulation pump (13) is a diaphragm pump or a jet pump.

9. The external spraying closed circulation gas fermentation reactor according to claim 8, characterized in that The liquid outlet end of the liquid guide tube II (12) is fixedly connected to the bottom of the fermentation reaction chamber (1).

10. The external spraying closed circulation gas fermentation reactor according to claim 1, characterized in that: The reactor further comprises a safety valve (8) fixedly mounted on the top of the fermentation reaction chamber (1).

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