Fermentation device for preparing ethanol by fermenting synthesis gas

Abstract

The invention discloses a fermentation device for preparing ethanol by fermentation of synthesis gas, and relates to the technical field of fermentation, the fermentation device comprises a fermentation tank, and also comprises a separation cylinder coaxially arranged in the fermentation tank, the upper end of the separation cylinder and the fermentation tank are arranged in a closed manner, the separation cylinder and the inner wall of the fermentation tank form a fermentation liquid circulation space, and the separation cylinder is arranged in the fermentation tank. A fermentation liquid inlet is formed in the uppermost circulation space, a fermentation liquid outlet is formed in the bottom of the fermentation tank, and a heat exchanger is arranged between the fermentation liquid inlet and the fermentation liquid outlet; the air supply unit is arranged on the fermentation tank, and is used for heating / cooling the fermentation liquor and simultaneously realizing the circulation of the fermentation liquor in the fermentation tank, so that the temperature in the fermentation tank can be controlled in real time according to the temperature in the fermentation tank by adjusting the circulation of the fermentation liquor, and the growth of microorganisms is more favorable; and meanwhile, the flowing fermentation liquid can be better and uniformly mixed when the synthesis gas is discharged.

Description

Technical Field

[0001] The invention relates to the technical field of fermentation, and in particular to a fermentation device for producing ethanol by fermenting synthetic gas. Background Art

[0003] Innovating fuel ethanol sources and developing new processes for non-grain ethanol production have become research hotspots at home and abroad. The use of syngas biofermentation to produce ethanol has the advantages of mild reaction conditions, high product selectivity, a wide range of raw material sources, and low-carbon sustainable development. It is a promising new renewable energy production process.

[0004] The mass transfer process of microbial uptake of gas substrates includes four steps: (1) transport of the gas substrate into the gas-liquid interface; (2) transport in the liquid culture medium; (3) transport of the mixed gas into the static liquid layer surrounding the bacteria; and (4) diffusion of the substrate into the microorganisms.

[0005] Then, during the actual fermentation process, the temperature in the fermentation tank cannot be regulated in real time, which affects the growth of the microbial colony. At the same time, the degree of dissolution of synthetic gas in the fermentation liquid is low, resulting in low efficiency of synthetic gas biological fermentation. For this reason, we designed a fermentation device for producing ethanol from synthetic gas.

[0006] The above contents are only used to assist in understanding the technical solution of the present invention, and do not constitute an admission that the above contents are the closest prior art. Summary of the invention

[0007] The object of the present invention is to provide a fermentation device for producing ethanol from syngas, so as to solve the problem that the temperature in the fermentation tank proposed in the above background technology cannot be regulated in real time, thereby affecting the growth of microbial colonies, and at the same time, the degree of dissolution of syngas in the fermentation liquid is low, resulting in low syngas biological fermentation efficiency.

[0008] To achieve the above object, the present invention provides the following technical solution: a fermentation device for producing ethanol from syngas, comprising a fermentation tank, and further comprising:

[0009] A separation cylinder is coaxially arranged inside the fermentation tank, the upper end of the separation cylinder is sealed with the fermentation tank, the separation cylinder and the inner wall of the fermentation tank form a circulation space for the fermentation liquid, a fermentation liquid inlet is arranged at the uppermost circulation space, a fermentation liquid outlet is arranged at the bottom of the fermentation tank, and a heat exchanger is arranged between the fermentation liquid inlet and the fermentation liquid outlet, for exchanging heat with the fermentation liquid discharged from the fermentation liquid outlet and then discharging it into the fermentation liquid inlet again;

[0010] The gas supply unit is arranged on the fermentation tank and is used for discharging the gas required by the fermentation microorganisms into the fermentation tank.

[0011] Preferably, multiple layers of semi-partitions are arranged from top to bottom in the circulation space, and two adjacent layers of the semi-partitions are symmetrically arranged up and down. The circulation space is composed of two adjacent partitions and the dividing cylinder and multiple small circulation channels that flow from top to bottom and from one side to the other in the fermentation tank.

[0012] Preferably, the air supply unit comprises:

[0013] A gas phase outlet is provided at the top of the fermentation tank and is used to discharge the gas formed by fermentation;

[0014] Two groups of gas phase air inlet pipes are symmetrically arranged at the bottom of the fermenter and extend through the fermenter to the inside of the fermenter. The gas phase air inlet pipes located inside the fermenter are evenly provided with air outlet holes for evenly discharging synthetic gas into the fermenter.

[0015] Preferably, the fermentation tank is provided with a stirring unit for fermenting the fermented product at the bottom of the fermentation tank;

[0016] The stirring unit comprises:

[0017] A stirring shaft coaxial with the fermenter and rotatably arranged, wherein one end of the stirring shaft extends to the bottom of the fermenter, and the other end passes through the top of the fermenter to the outside of the fermenter;

[0018] A rotating motor is fixed to the top of the fermentation tank through a fixing plate, and a rotating end of the rotating motor is connected to the stirring shaft to drive the stirring shaft to rotate;

[0019] A plurality of stirring blades are evenly arranged below the middle of the stirring shaft, and are used to stir the fermented material at the bottom of the fermentation tank, so that the fermented material is fully contacted and integrated with the fermentation liquid, and to break the bubbles generated by the fermentation.

[0020] Preferably, the fermentation tank located at the gas outlet of the gas phase air inlet pipe is provided with a spray device for uniformly mixing the synthesis gas with the fermentation liquid in cooperation with a stirring unit.

[0021] Preferably, the injection device comprises:

[0022] A bacterial microorganism layer is fixedly arranged on the inner wall of the fermentation tank by a fixing frame, and a plurality of leakage holes with decreasing radius from bottom to top are evenly arranged on the bacterial microorganism layer;

[0023] A plurality of arc-shaped top covers are arranged above each leakage hole.

[0024] Preferably, a filter is provided at the gas phase outlet.

[0025] Compared with the prior art, the present invention has the following beneficial effects:

[0026] The present invention heats / cools the fermentation liquid and realizes the circulation of the fermentation liquid in the fermenter. The temperature in the fermenter can be controlled in real time by adjusting the circulation of the fermentation liquid according to the temperature in the fermenter, thereby making the growth of microorganisms more favorable. At the same time, the flowing fermentation liquid can be better evenly mixed when the synthesis gas is discharged. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0028] Figure 2 It is a partial cross-sectional view of the interior of the fermentation tank of the present invention;

[0029] Figure 3 The overall structure diagram of the injection device of the present invention;

[0030] Figure 4 It is a front cross-sectional view of the fermentation tank of the present invention;

[0031] Figure 5 for Figure 4 Enlarged view of point A in the middle.

[0032] Figure numerals: 1-fermentation tank; 2-partition cylinder; 3-circulation space; 31-semi-partition; 4-fermentation liquid inlet; 5-fermentation liquid outlet; 6-gas supply unit; 61-gas phase outlet; 62-gas phase air inlet pipe; 63-air outlet; 7-stirring unit; 71-stirring shaft; 72-rotating motor; 73-stirring blade; 8-injection device; 81-bacteria microbial layer; 82-leakage hole; 83-arc top cover. DETAILED DESCRIPTION

[0033] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0034] See also Figure 1-5 The present invention provides a technical solution: a fermentation device for producing ethanol from syngas, comprising a fermentation tank 1, and further comprising:

[0035] A separation cylinder 2 is coaxially arranged inside the fermentation tank 1, the upper end of the separation cylinder 2 and the fermentation tank 1 are sealed, the separation cylinder 2 and the inner wall of the fermentation tank 1 form a circulation space 3 for the fermentation liquid, a fermentation liquid inlet 4 is arranged at the uppermost circulation space 3, a fermentation liquid outlet 5 is arranged at the bottom of the fermentation tank 1, and a heat exchanger is arranged between the fermentation liquid inlet 4 and the fermentation liquid outlet 5, for exchanging heat with the fermentation liquid discharged from the fermentation liquid outlet 5 and then discharging it again from the fermentation liquid inlet 4;

[0036] The gas supply unit 6 is disposed on the fermentation tank 1 and is used to discharge the gas required by the fermentation microorganisms into the fermentation tank 1 .

[0037] The circulation space 3 is provided with multiple layers of half partitions 31 from top to bottom, and two adjacent layers of the half partitions 31 are symmetrically arranged up and down. The circulation space 3 is composed of two adjacent partitions, the separation cylinder 2, and a plurality of small circulation channels flowing from top to bottom and from one side to the other side of the fermentation tank 1;

[0038] Before the fermentation work is carried out, the fermentation liquid is first discharged from the fermentation liquid inlet 4 through the pump, and the fermentation liquid will flow to the bottom of the fermentation tank 1 through the circulation space 3, and the fermentation liquid will bury the bottom of the fermentation tank 1. Then the fermentation liquid is stopped from being discharged, and then the pump is connected to one end of the heat exchanger, and the other end of the heat exchanger is connected to the fermentation liquid outlet 5. In the actual fermentation process, the pump and the heat exchanger can work according to the temperature in the fermentation tank 1, that is, when the temperature in the fermentation tank 1 is too low, which is not conducive to the survival of the fermented microorganisms, the pump and the heat exchanger work, the fermentation liquid outlet 5 is opened, and the fermentation liquid will flow to the heat exchanger for heating, and then the heated fermentation liquid will be discharged from the fermentation liquid inlet 4 again through the pump, and then pass through a plurality of small circulation channels in sequence, so as to increase the temperature in the fermentation tank 1. At the same time, when the flowing fermentation liquid impacts from top to bottom in the fermentation tank 1, it can also better merge with the synthesis gas, thereby improving the contact efficiency with the microorganisms and improving the fermentation rate.

[0039] And, the air supply unit 6 comprises:

[0040] A gas phase outlet 61 is provided at the top of the fermentation tank 1 and is used to discharge the gas formed by fermentation;

[0041] Two groups of gas-phase air inlet pipes 62 are symmetrically arranged at the bottom of the fermentation tank 1 and extend through the fermentation tank 1 to the inside of the fermentation tank 1. The gas-phase air inlet pipes 62 located inside the fermentation tank 1 are evenly provided with air outlet holes 63 for evenly discharging synthetic gas into the fermentation tank 1. The two groups of symmetrically arranged gas-phase air inlet pipes 62 are arranged to avoid motion interference with the stirring unit 7.

[0042] At the same time, the fermentation tank 1 is provided with a stirring unit 7 for fermenting the fermented material at the bottom of the fermentation tank 1;

[0043] The stirring unit 7 comprises:

[0044] A stirring shaft 71 is coaxial with the fermentation tank 1 and is rotatably arranged, wherein one end of the stirring shaft 71 extends to the bottom of the fermentation tank 1, and the other end passes through the top of the fermentation tank 1 to the outside of the fermentation tank 1;

[0045] A rotating motor 72 is fixed to the top of the fermentation tank 1 through a fixing plate, and a rotating end of the rotating motor 72 is connected to the stirring shaft 71 to drive the stirring shaft 71 to rotate;

[0046] A plurality of stirring blades 73 are evenly arranged below the middle of the stirring shaft 71 to stir the fermented material at the bottom of the fermentation tank 1 so that it can fully contact and fuse with the fermentation liquid and break up the bubbles generated by the fermentation.

[0047] In addition, an injection device 8 is provided on the fermentation tank 1 at the position of the gas outlet 63 of the gas phase air inlet pipe 62 , which is used for uniformly mixing the synthesis gas with the fermentation liquid under the action of the stirring unit 7 .

[0048] Wherein, the injection device 8 comprises:

[0049] The multi-layer flora microorganism layer 81 is fixedly arranged on the inner wall of the fermentation tank 1 by a fixing frame, and a plurality of leak holes 82 with decreasing radius from bottom to top are evenly arranged on the flora microorganism layer 81;

[0050] A plurality of arc-shaped top covers 83 are arranged above each leakage hole 82;

[0051] When the stirring unit 7 is stirring, and at the same time the synthetic gas is discharged into the fermentation tank 1 through the gas phase air inlet pipe 62 by the air compressor, the synthetic gas will be ejected from the leak hole 82 with a gradually decreasing radius, so that due to the obstruction of the upper top cover when ejecting, a low-pressure area is formed at this position, and when the fermentation liquid is injected into this place, turbulence and shear effect will be formed with the synthetic gas, and the fermentation liquid will be evenly mixed with the synthetic gas and stirred fully, thereby improving the utilization rate of the synthetic gas, and through the setting of the multi-layer bacterial microbial layer 81, the gas can be mixed with the fermentation liquid multiple times when it rises.

[0052] Finally, a filter is provided at the gas phase outlet 61 to eliminate bubbles in the exhaust gas.

Claims

1. A fermentation device for producing ethanol from synthesis gas, comprising a fermentation tank (1), characterized in that: Also includes: A separation cylinder (2) is coaxially arranged inside the fermentation tank (1); the upper end of the separation cylinder (2) and the fermentation tank (1) are sealed; the separation cylinder (2) and the inner wall of the fermentation tank (1) form a circulation space (3) for the fermentation liquid; a fermentation liquid inlet (4) is arranged at the top of the circulation space (3); a fermentation liquid outlet (5) is arranged at the bottom of the fermentation tank (1); a heat exchanger is arranged between the fermentation liquid inlet (4) and the fermentation liquid outlet (5) for exchanging heat with the fermentation liquid discharged from the fermentation liquid outlet (5) and then discharging it into the fermentation liquid inlet (4) again; The gas supply unit (6) is arranged on the fermentation tank (1) and is used to discharge the gas required by the fermentation microorganisms into the fermentation tank (1).

2. The fermentation device for producing ethanol from synthesis gas according to claim 1, characterized in that: Multiple layers of half partitions (31) are arranged from top to bottom in the circulation space (3), and two adjacent layers of the half partitions (31) are arranged symmetrically in the upper and lower directions. The circulation space (3) is composed of two adjacent partitions, the dividing cylinder (2) and a plurality of small circulation channels for the fermentation tank (1) to flow from top to bottom and from one side to the other.

3. The fermentation device for producing ethanol from synthesis gas according to claim 1, characterized in that: The air supply unit (6) comprises: A gas phase outlet (61) is provided at the top of the fermentation tank (1) and is used to discharge the gas generated by fermentation; Two groups of gas phase air inlet pipes (62) are symmetrically arranged at the bottom of the fermenter (1) and penetrate the fermenter (1) to extend into the interior of the fermenter (1). The gas phase air inlet pipes (62) located inside the fermenter (1) are evenly distributed with air outlet holes (63) for evenly discharging synthetic gas into the fermenter (1).

4. The fermentation device for producing ethanol from synthesis gas according to claim 3, characterized in that: The fermentation tank (1) is provided with a stirring unit (7) for fermenting the fermented material at the bottom of the fermentation tank (1); The stirring unit (7) comprises: a stirring shaft (71) coaxial with the fermentation tank (1) and rotatably arranged, wherein one end of the stirring shaft (71) extends to the bottom of the fermentation tank (1), and the other end passes through the top of the fermentation tank (1) to the outside of the fermentation tank (1); A rotating motor (72) is fixed to the top of the fermentation tank (1) via a fixing plate, and a rotating end of the rotating motor (72) is connected to the stirring shaft (71) to drive the stirring shaft (71) to rotate; A plurality of stirring blades (73) are evenly arranged below the middle of the stirring shaft (71) and are used to stir the fermented material at the bottom of the fermentation tank (1) so that it is fully in contact with and integrated with the fermentation liquid, and to break up bubbles generated by the fermentation.

5. The fermentation device for producing ethanol from synthesis gas according to claim 4, characterized in that: The fermentation tank (1) is provided with a spray device (8) at the position of the gas outlet (63) of the gas phase air inlet pipe (62), which is used to uniformly mix the synthesis gas with the fermentation liquid under the action of the stirring unit (7).

6. The fermentation device for producing ethanol from synthesis gas according to claim 5, characterized in that: The injection device (8) comprises: A bacterial microorganism layer (81) is fixedly mounted on the inner wall of the fermentation tank (1) via a fixing frame, and a plurality of leak holes (82) with decreasing radius from bottom to top are evenly arranged on the bacterial microorganism layer (81); A plurality of arc-shaped top covers (83) are arranged above each leakage hole (82).

7. The fermentation device for producing ethanol from synthesis gas according to claim 3, characterized in that: A filter screen is provided at the gas phase outlet (61).

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