Dynamic point stirring device, extra large anaerobic fermentation tank and fermentation process

Abstract

The present invention discloses a moving-point stirring device, an extra-large anaerobic fermentation tank and a fermentation process. The moving-point stirring device includes a central column, a cross beam and a plurality of stirrers. The central column is disposed inside the fermentation tank; the cross beam is installed on the central column and can make a circular motion along the tank body of the fermentation tank; the plurality of stirrers are respectively suspended below the cross beam, including a stirring shaft and stirring blades provided on the stirring shaft. The stirring shaft can drive the stirring blades to rotate self-rotationally, and the stirring blades can revolve around the central column along with the rotation of the cross beam. The extra-large anaerobic fermentation tank is provided with the moving-point stirring device, and the fermentation process is carried out using the extra-large anaerobic fermentation tank. The moving-point stirring device provided by the present invention is particularly suitable for an extra-large fermentation tank with a single volume greater than 12000 m<supgt;3< / supgt>. Its stirring intensity is uniform and adjustable, there will be no stirring dead zone during the stirring process, and it has strong adaptability to special working conditions.

Description

Technical Field

[0001] The invention relates to the technical field of anaerobic fermentation, and in particular to a dynamic point stirring device suitable for performing anaerobic wet fermentation of biomass to prepare biogas, an extra-large anaerobic fermentation tank and a fermentation process. Background Art

[0002] Fermentation tank refers to the device used for microbial fermentation in industry. Its main body is generally a main cylinder made of stainless steel plate, with a volume of 1m 3 To hundreds of meters 3 The components of the fermentation tank mainly include: a tank body used to culture and ferment various bacteria, a stirring paddle in the tank body, which is used to stir continuously during the fermentation process to achieve mass transfer effects in the reaction tank, etc. Fermentation tanks can be divided into laboratory small fermentation tanks, pilot production fermentation tanks, large fermentation tanks, etc. according to their scope of use.

[0003] With the improvement of production technology, the volume of anaerobic wet fermentation tanks in China has gradually expanded to about 12,000-40,000m 3 In order to ensure the reasonable contact between the new material and the anaerobic microorganisms in the extra-large fermentation tank, the existing technology usually adopts a multi-point oblique stirring device ( Figure 1 )、Submersible Mixing Device( Figure 2 ) or multi-point oblique entry and submersible composite mixing device ( Figure 3 ) for intermittent stirring.

[0004] However, both the multi-point oblique entry stirring device and the submersible stirring device have the following problems during the stirring process:

[0005] (1) Usually, during the stirring process, the agitator will have the problem of strong central flow field and weak peripheral flow field. Whether it is a multi-point oblique stirring device or a submersible stirring device, it is limited by the strength characteristics of the agitator flow field distribution, and it is difficult to achieve uniform stirring intensity in a super-large anaerobic tank. This will result in that if the stirring intensity of the central flow field meets the requirements of the anaerobic reaction, the peripheral flow field area will not meet the requirements or even form a dead zone. The dead zone will form local acidification and affect the efficiency of the anaerobic reaction, and even fail to produce methane; if the stirring intensity is increased so that the peripheral flow field area meets the requirements of the anaerobic reaction, the central flow field area will form excessive stirring, which will increase the hydrogen partial pressure, resulting in a decrease in gas production capacity, and thus reduce the efficiency of the anaerobic reaction.

[0006] (2) Due to the fixed-point installation and operation of the agitator, its adaptability to special working conditions is poor. For example, if the feed amount exceeds the design amount or the reaction tank is restarted after being shut down for some reason, the uniformity of the stirring will be affected.

[0007] (3) During the stirring process, the liquid surface constantly fluctuates, and the relative distance between the agitator blades and the liquid surface is unstable, so floating objects such as straw floating on the liquid surface cannot be immersed in the mixing. Summary of the invention

[0008] The object of the present invention is to overcome the defects in the prior art, thereby providing a dynamic point stirring device, an extra-large anaerobic fermentation tank and a fermentation process. The dynamic point stirring device can be applied to stirring tanks of any size, especially those with a single volume greater than 12000m 3 The extra-large fermentation tank has uniform and adjustable stirring intensity. There will be no stirring dead zone during the stirring process, and it has strong adaptability to special working conditions. The extra-large anaerobic fermentation tank can work continuously for 24 hours without interruption and maintain dynamic balance. The fermentation process can ensure that the microbial residence time is greater than the solid residence time and greater than the water residence time.

[0009] In order to achieve the above object, the present invention provides the following technical solutions:

[0010] A dynamic point stirring device, comprising:

[0011] A central column, built into the fermenter;

[0012] A crossbeam, mounted on the central column and capable of performing circular motion along the body of the fermentation tank;

[0013] A plurality of stirrers are respectively suspended below the cross beam, and include a stirring shaft and stirring blades arranged on the stirring shaft. The stirring shaft can drive the stirring blades to rotate, and the stirring blades can revolve around the central column as the cross beam rotates.

[0014] As an practicable manner, a hydraulic rotator is installed on the central column, and the hydraulic rotator includes a hydraulic motor and a parallel gear reducer; the hydraulic motor is connected to the hydraulic station outside the fermentation tank to provide driving force for the parallel gear reducer, and the output shaft of the parallel gear reducer is a hollow rotating shaft, and the hollow rotating shaft is sleeved on the outside of the central column to provide a bearing position for connecting the crossbeam; wherein a hydraulic valve group is also provided on the hollow rotating shaft, and the hydraulic valve group is used to control the pressure, flow and direction of the hydraulic oil.

[0015] As an implementable method, the agitator is a hydraulic agitator, and a hydraulic oil distributor connected to the hydraulic station is also provided on the central column. The hydraulic oil distributor is respectively connected to the hydraulic valve group on the hollow rotating shaft and each of the hydraulic agitators. Under the action of the hydraulic station, the hydraulic oil distributor provides hydraulic energy to the hydraulic motor and the hydraulic agitator.

[0016] As an implementable manner, a plurality of floating boats are provided below the cross beam, and the floating boats are used to carry the cross beam on the liquid surface.

[0017] As an implementable manner, a folding plate is provided between the cross beam and the hollow rotating shaft, and the folding plate includes at least a first connecting plate and a second connecting plate hinged to each other, the free end of the first connecting plate is fixedly connected to the hollow rotating shaft, and the free end of the second connecting plate is hinged to the cross beam.

[0018] As an practicable manner, a rotating track adapted to the rotating track of the crossbeam is provided on the inner wall of the fermentation tank, and the free end of the crossbeam is rollably disposed on the rotating track.

[0019] As an practicable manner, the hollow rotating shaft is passed through the middle of the crossbeam, the crossbeam is equal in length to the diameter of the fermentation tank, rollers are provided at both free ends of the crossbeam, and the crossbeam is rollingly connected to the rotating track via the rollers.

[0020] As an implementable manner, there are multiple cross beams, each of which is connected to the hollow rotating shaft and performs circular motion as the hollow rotating shaft rotates.

[0021] As an practicable manner, a plurality of stirring blades are provided on the rotating shaft of each of the stirrers, and the stirring blades closest to the liquid surface can form vortices at the liquid surface corresponding thereto.

[0022] A super-large anaerobic fermentation tank comprises a tank body and a dynamic point stirring device arranged in the tank body, wherein the bottom of the tank body is provided with N evenly distributed feed ports, and the top of the tank body is provided with N discharge ports corresponding to the feed ports in the axial direction, wherein N≥4, the feed ports are used to continuously and alternately transport the materials to be fermented into the fermentation tank, and the discharge ports are used to continuously and alternately discharge the fermented materials.

[0023] A fermentation process, using the super-large anaerobic fermentation tank for fermentation, comprises the following steps:

[0024] S1. Divide the fermentation tank into N sector-shaped areas according to the number of the discharge ports / feed ports, and each sector-shaped area corresponds to one discharge port and one feed port, and the N sector-shaped areas are numbered sequentially;

[0025] S2, the material to be fermented is put into the feed port of the i-th sector area, the initial value of i is 1, and the dynamic point stirring device is started and the discharge port of the m-th sector area is opened, wherein m≠i, and the stirring range of the dynamic point stirring device is controlled to avoid the m-th sector area for reciprocating stirring;

[0026] S3, after stirring for 2-3 hours, let i=i+1 and execute step S2, until i is greater than N and execute step S4;

[0027] S4, resetting i to the initial value, and re-performing step S2 to achieve 24-hour uninterrupted feeding and discharging.

[0028] As an practicable manner, the mth sector area is the sector area farthest from the delivery point of the material to be fermented.

[0029] Compared with the prior art, the present invention has the following beneficial effects:

[0030] The dynamic point stirring device provided by the present invention is completely arranged in a fermentation tank, and mainly comprises a column, a crossbeam and a plurality of stirrers arranged under the crossbeam, wherein the crossbeam can make a circular motion around the column and drive the stirrer to make a revolution motion, and the stirrer can be arranged at various positions of the crossbeam, when the crossbeam makes a circular motion along the tank body, the stirrer rotates, and can achieve full coverage stirring of the mixture in the fermentation tank with the movement of the crossbeam, in addition, since the present invention is mainly used for a fermentation tank, and the raw materials of the fermentation tank mostly contain light floating objects such as straw, these floating objects are difficult to settle and are fully stirred by the stirrer, and float on the liquid surface for many years to form scabs and shells, therefore, the height of the liquid surface or the crossbeam can be adjusted to make it equal to the liquid surface, and when making a circular motion, the floating objects are disturbed, so that the floating objects are immersed in water for many times and settle in the mixture to be stirred by the stirring blades, that is, the crossbeam also participates in the stirring, thereby achieving more sufficient mixing.

[0031] In the present application, a stirring mode of revolution and rotation is set in the fermentation tank, and the revolution can also participate in the stirring. Therefore, when the crossbeam revolves, the stirring blades can fully cover various areas in the liquid for stirring, and the crossbeam can also disturb the floating objects on the liquid surface, thereby avoiding the existence of a stirring dead zone. In addition, the stirring device of the present application can be applied to stirring tanks of any size. It only needs to set a suitable crossbeam length and the number of agitators according to the size of the stirring tank, and the stirring intensity is uniform and adjustable. Finally, the crossbeam and agitator of the present application are both installed at a moving point, so even if the feed amount exceeds the design amount or the discharge amount is greater than the feed amount, or the reaction tank is restarted after being shut down for some reason, it will not affect the uniformity of stirring.

[0032] The extra-large anaerobic fermentation tank of the present application is provided with a feed inlet at the bottom and a discharge outlet at the top, which is conducive to the anaerobic fermentation. The feed inlet is used to continuously and alternately transport the material to be fermented into the fermentation tank, and the discharge outlet is used to continuously and alternately discharge the fermented material. Therefore, the material can be directly discharged through the overflow outlet, reducing energy consumption.

[0033] The fermentation process of the present application is based on the setting of the discharge port and the feed port in the extra-large anaerobic fermentation tank, that is, the discharge port and the feed port correspond one-to-one in the axial direction, and the N sector-shaped areas divided into equal parts of the fermentation tank according to the number of the discharge port / feed port all have the feed port and the discharge port, wherein the feed port for inputting the material to be fermented and the discharge port for discharging the fermentation-completed material do not correspond in the axial direction, that is, the feed port for inputting the material to be fermented is located in the i-th sector-shaped area, and the discharge port for discharging the material is in the m-th sector-shaped area, m≠i, and it is best that the two are located in a diagonal position, that is, they are relatively arranged, and during the stirring process, the revolution range of the moving point stirring device avoids the m-th sector-shaped area, and only moves along the tank body of the fermentation tank in other areas except this area. Repeat the operation until the material is discharged from the discharge port of the mth sector area, and then feed from the i+1th sector area, and at the same time select the mth sector area which is not in the same sector area as the i+1th sector area to discharge. Of course, the mth sector area is preferably the sector area farthest from the point where the material to be fermented is placed at this time. And so on, feed in different sector areas in turn along the circumferential direction of the fermenter, and discharge at the discharge port that does not correspond to the actual feed port, preferably at a relative position. Feed and discharge are carried out uninterruptedly for 24 hours, so as to achieve in the fermenter: microbial residence time (MRT)> solid residence time (SRT)> hydraulic retention time (HRT), and obtain good anaerobic fermentation efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0035] Figure 1 It is a multi-point oblique stirring device in the prior art;

[0036] Figure 2 It is a submersible stirring device in the prior art;

[0037] Figure 3 It is a multi-point oblique entry and submersible composite stirring device in the prior art;

[0038] Figure 4 A dynamic point stirring device provided by one embodiment of the present invention;

[0039] Figure 5 A dynamic point stirring device provided by another embodiment of the present invention;

[0040] Figure 6 for Figure 5 A partial enlarged view of point I in the middle;

[0041] Figure 7 for Figure 5 A partial cross-sectional view at position I in the middle;

[0042] Figure 8 A schematic diagram of the structure of an extra-large anaerobic fermentation tank provided in one embodiment of the present invention.

[0043] Description of reference numerals:

[0044] 1. Central column; 11. Column seat; 12. Column rod; 2. Crossbeam; 21. Floating boat; 22. Folding plate; 23. Roller; 221. First connecting plate; 222. Second connecting plate; 3. Agitator; 31. Agitator shaft; 32. Agitator blade; 4. Fermentation tank; 41. Rotating track; 5. Hydraulic rotator; 51. Hydraulic motor; 52. Parallel gear reducer; 521. Hollow shaft; 522. Hole; 6. Hydraulic oil distributor; 61. Cylinder; 62. Distributor hollow shaft; 63. Oil valve seat; 7. Tank; 71. Feed inlet; 72. Discharge outlet; 73. The i-th sector area; 74. The m-th sector area. DETAILED DESCRIPTION

[0045] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. 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.

[0046] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0047] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0048] In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0049] Embodiment 1

[0050] See also Figure 4-5 The present invention provides a dynamic point stirring device, including a central column 1, a crossbeam 2 and a plurality of stirrers 3, wherein the central column 1 is built into a fermentation tank 4, and includes a column seat 11 and a column rod 12 coaxially arranged from top to bottom, the column seat 11 is used to support the column rod 12, and the column rod 12 is used to support the membrane top of the fermentation tank 4; the crossbeam 2 is installed on the central column 1, and can be installed through one end of the crossbeam 2 or through the middle of the crossbeam 2, and the crossbeam 2 can rotate relative to the central column 1, so as to achieve circular motion along the tank body of the fermentation tank 4; the stirrers 3 are respectively suspended below the crossbeam 2, and in order to fully cover and distribute as evenly as possible, the stirrers 3 include a stirring shaft 31 and stirring blades 32 arranged on the stirring shaft 31, the stirring shaft 31 can drive the stirring blades 32 to rotate, and the stirring blades 32 can revolve around the central column with the rotation of the crossbeam 2.

[0051] The dynamic point stirring device provided by the present invention is completely arranged in the fermentation tank 4, mainly comprising a central column 1, a crossbeam 2 and a plurality of stirrers 3 arranged below the crossbeam 2, wherein the crossbeam 2 can make a circular motion around the central column 1 and drive the stirrer 3 to make a revolution motion, and the stirrer 3 can be arranged at various positions of the crossbeam 2, when the crossbeam 2 makes a circular motion along the tank body, the stirrer 3 rotates, and can achieve full coverage stirring of the mixture in the fermentation tank 4 with the movement of the crossbeam 2, in addition, since the present invention is mainly used for the fermentation tank 4, and the raw materials of the fermentation tank 4 mostly contain light floating objects such as straw, these floating objects are difficult to settle and are fully stirred by the stirrer 3, floating on the liquid surface for many years and forming scabs, therefore, the height of the liquid surface or the crossbeam 2 can be adjusted to be equal to the liquid surface, and when making a circular motion, the floating objects are disturbed, so that the floating objects are immersed in water for many times and settle in the mixture and are stirred by the stirring blades 32, that is, the crossbeam 2 also participates in the stirring, thereby achieving more sufficient mixing. In the present application, a stirring mode of revolution and rotation is set in the fermenter 4, and the revolution can also participate in the stirring. Therefore, when the crossbeam 2 revolves, the stirring blades 32 can fully cover various areas in the liquid for stirring, and the crossbeam 2 can also disturb the floating objects on the liquid surface, thereby avoiding the existence of a stirring dead zone. In addition, the stirring device of the present application can be applied to fermenters 4 of any size. It only needs to set a suitable length of the crossbeam 2 and the number of agitators 3 according to the size of the fermenter 4, and the stirring intensity is uniform and adjustable. Finally, the crossbeam 2 and the agitator 3 of the present application are both installed at a moving point. Therefore, even if the feed amount exceeds the design amount or the discharge amount is greater than the feed amount, or the reaction tank is restarted after being shut down for some reason, the stirring uniformity will not be affected.

[0052] Of course, the power sources of the cross beam 2 and the agitator 3 of the present application can be various, such as manual, electric, pneumatic and hydraulic. Considering that the present application is an anaerobic fermentation tank, which is mainly used to produce biogas, if it is driven by electric or other power sources, there will be a safety hazard of sparks igniting the fermentation tank during operation, and it is costly to set the electric drive device in the anaerobic fermentation tank 4. In this embodiment, hydraulic drive is mainly used to provide power for the rotation of the cross beam 2 and the agitator 3. Please continue to refer to the detailed description. Figure 4-5 The entire hydraulic system is at least provided with a hydraulic station (not shown in the figure) outside the fermentation tank 4 and a hydraulic rotary device 5 and a hydraulic oil distributor 6 provided on the central column 1, see Figure 6 The hydraulic rotator 5 includes a hydraulic motor 51 and a parallel gear reducer 52. The hydraulic motor 51 is arranged on the column seat 11 and can be directly connected to the hydraulic station outside the fermentation tank 4. The hydraulic station is used to pump hydraulic oil to the hydraulic motor 51 to rotate the hydraulic motor 51, thereby providing driving force for the parallel gear reducer 52. The parallel gear reducer 52 can be a planetary reducer or a transmission gear drive. The principle of the planetary reducer is a power transmission mechanism that uses a gear speed converter to reduce the number of revolutions of the motor to the desired number of revolutions and obtain a larger torque. The small gear on the transmission shaft of the planetary reducer meshes with the large gear on the output shaft to achieve the purpose of deceleration. It has the characteristics of small radial size, safe and reliable braking, the output shaft can withstand large radial and axial external forces, high starting efficiency, good low-speed stability, high transmission efficiency, low noise, and good economy.

[0053] In this example, see Figure 7 The output shaft of the small gear in the parallel gear reducer 52 is connected to the hydraulic motor 51, and the output shaft of the large gear is a hollow rotating shaft 521. The hollow rotating shaft 521 is sleeved on the outside of the central column 1 to provide a bearing position for connecting the crossbeam 2; and the end of the side wall of the hollow rotating shaft 521 is also axially opened with a plurality of holes 522 connected to the hydraulic station for circulating hydraulic oil. A hydraulic valve group (not shown in the figure) is arranged in each hole 522, and the hydraulic valve group is used to control the pressure, flow and direction of the hydraulic oil.

[0054] Of course, in order to fully prevent explosion, the agitator 3 can also be set as a hydraulic agitator. In this case, please continue to refer to Figure 6, a hydraulic oil distributor 6 directly connected to the hydraulic station is also required on the central column 1. The hydraulic oil distributor 6 is also connected to the hydraulic valve group on the hollow shaft and each hydraulic agitator 3 respectively, that is, the hydraulic oil is first transported to the hydraulic oil distributor 6 through the hydraulic station. The hydraulic oil distributor 6 transmits a part of the hydraulic oil to the hole of the hollow shaft as needed, and finally flows to the hydraulic motor 51, and the hydraulic motor 51 provides driving force to the parallel gear reducer 52; another part of the hydraulic oil is transmitted to the hydraulic agitator 3 to provide driving force for it. In this embodiment, the hydraulic oil distributor 6 includes a coaxially arranged cylinder 61, a distributor hollow shaft 62 and an oil circuit valve seat 63. The cylinder 61 is used to contain hydraulic oil, and is directly connected to the hydraulic station and each hydraulic agitator 3. The distribution The distributor hollow shaft 62 is sleeved on the column rod 12 and is flange-connected to the hollow rotating shaft 521. At the same time, the distributor hollow shaft 62 is also used to connect the cylinder 61 and the hollow rotating shaft 521 so that the hydraulic oil can flow to the hydraulic motor 51. In this embodiment, the distributor hollow shaft 62 can rotate with the hollow rotating shaft 521, and the cylinder 61 is directly fixed on the parallel gear reducer 52, that is, the distributor hollow shaft 62 rotates relative to the cylinder 61 driven by the hollow rotating shaft 521. At this time, the distributor hollow shaft 62 can be used to provide a bearing position for installing the crossbeam 2, and the oil circuit valve seat 63 is used to control the pressure, flow, etc. of the hydraulic oil entering and exiting the hydraulic agitator 3, and the hydraulic valve group is used to control the pressure, flow, etc. of the hydraulic oil entering and exiting the hollow rotating shaft 521, that is, the hydraulic motor 51.

[0055] The crossbeam 2 in this application has two forms, one is a floating crossbeam, and the other is a track crossbeam, as follows:

[0056] See also Figure 4 When it is a track beam (suitable for materials with less floating objects), the beam 2 runs smoothly and runs at a specified height of the fermentation tank 4, that is, one end of the beam 2 is installed on the hollow rotating shaft 521 or the distributor hollow shaft 62, and the other end is supported by the fermentation tank 4. For example, a rotating track 41 that is compatible with the rotating trajectory of the beam 2 is set on the inner wall of the fermentation tank 4, and a roller 23 that is compatible with the rotating track 41 is installed at the free end of the beam 2, so that it can be rolled on the rotating track 41.

[0057] Of course, the middle of the cross beam 2 can also be fixed on the hollow rotating shaft 521 or the distributor hollow shaft 62, and the cross beam 2 and the fermentation tank 4 are set to have the same diameter, and rollers are set at both free ends of the cross beam 2, so that the two ends of the cross beam 2 are rollingly connected to the rotating track 41 through the rollers 23. Agitators 3 are arranged on both sides of the cross beams 2 centered on the central column 1, which can further increase the coverage frequency of stirring, thereby improving the stirring efficiency.

[0058] See also Figure 5When it is a floating beam (suitable for materials with more floating objects), a plurality of pontoons 21 can be arranged under the beam 2, and the pontoons 21 are used to carry the beam 2 on the liquid surface. This method realizes the disturbance of floating objects through the pontoons 21. Compared with the disturbance directly through the beam 2, the resistance is small and corrosion-resistant, which can increase the service life of the beam 2, reduce the work done by the hydraulic motor 51, and there is no need to set a rotating track 41 along the circumference of the fermentation tank body, which relatively reduces the production cost and maintenance cost. Considering that the liquid level will change to a certain extent as the fermentation proceeds or the operations such as feeding and discharging, the present embodiment also sets a folding plate 22 between the beam 2 and the hollow shaft 521, and the folding plate 22 at least includes a first connecting plate 221 and a second connecting plate 222 that are hinged to each other, the free end of the first connecting plate 221 is fixedly connected to the hollow shaft 521, and the free end of the second connecting plate 222 is hinged to the beam 2. In this way, the cross beam 2 can swing up and down with the liquid level under the action of the floating boat and can rotate along the circumference of the tank body under the drive of the hydraulic rotator 5. Of course, the folding plate 22 can be a plurality of connecting plates hinged together, which can further increase its flexibility.

[0059] See also Figure 6 In this embodiment, the cross beam 2 can be set to be multiple, and accordingly, the folding plate 22 is also multiple, each folding plate 22 independently corresponds to a hollow rotating shaft 521 and a distributor hollow shaft 62, and each folding plate 22 can be installed on the corresponding hollow rotating shaft 521 or the corresponding distributor hollow shaft 62. With the rotation of the hollow rotating shaft 521 or the distributor hollow shaft 62, each cross beam 2 is driven to float on the liquid surface and make a circular motion along the tank body of the fermentation tank 4.

[0060] Multiple agitators 3 can be set on each beam 2 according to the process requirements. The revolution speed of the beam 2, the number of agitators 3, and the rotation speed should also be set according to the needs of anaerobic fermentation. Excessive stirring should not be done to increase the hydrogen partial pressure. Of course, the present application is not limited to anaerobic fermentation, but can also be applied to any other form of reaction tank, such as aerobic fermentation. At this time, the rotation speed can be increased or the number of agitators 3 can be increased to achieve sufficient stirring.

[0061] In order to better break the shells of floating objects, the present embodiment provides a plurality of stirring blades 32 on the stirring shaft 31 of each stirrer 3. Figure 4-5 , wherein at least the stirring blade 32 closest to the liquid surface can form a vortex at the liquid surface corresponding thereto, so that when the crossbeam 2 revolves, the pontoon 21 disturbs the floating objects and breaks them up, and the scattered floating objects move to the vortex part of the liquid surface and are sucked into the mixture, and further mixed evenly under the action of the stirring blade 32, wherein each pontoon 21 preferably corresponds to at least one vortex around the side to facilitate uniform mixing.

[0062] Example 2

[0063] See also Figure 8 The present embodiment provides an extra-large anaerobic fermentation tank, including a tank body 7, in which a dynamic point stirring device as described in Example 1 is provided, the bottom of the tank body 7 is provided with N evenly distributed feed ports 71, and the top of the tank body 7 is provided with N discharge ports 72 corresponding to the feed ports 71 in the axial direction, wherein N ≥ 4, the feed ports 71 are used to continuously and alternately transport the material to be fermented into the fermentation tank 4, and the discharge ports 72 are used to continuously and alternately discharge the fermented material.

[0064] The extra-large anaerobic fermentation tank of the present application is provided with a feed port 71 at the bottom and a discharge port 72 at the top, which is conducive to the anaerobic fermentation. The feed port 71 is used to continuously and alternately transport the material to be fermented into the fermentation tank 4, and the discharge port 72 is used to alternately discharge the fermented material. Therefore, the overflow can be directly discharged through the discharge port 72 to reduce energy consumption.

[0065] Example 3

[0066] See also Figure 8 This embodiment provides a fermentation process, which uses the extra-large anaerobic fermentation tank described in Example 2 for fermentation, including the following steps:

[0067] S1. Divide the fermentation tank 4 into N sector-shaped areas according to the number of discharge ports 72 / feed ports 71, and each sector-shaped area corresponds to one discharge port 72 and one feed port 71, and number the N sector-shaped areas sequentially;

[0068] S2, the material to be fermented is fed into the feed port of the i-th sector area 73, the initial value of i is 1, and the dynamic point stirring device is started and the discharge port of the m-th sector area 74 is opened, wherein m≠i, and the stirring range of the dynamic point stirring device is controlled to avoid the m-th sector area 74 for reciprocating stirring;

[0069] S3, after stirring for 2-3 hours, let i=i+1 and execute step S2, until i is greater than N and execute step S4;

[0070] S4, reset i to the initial value, and re-execute step S2 to achieve 24-hour uninterrupted feeding and discharging.

[0071] The fermentation process of the present application is based on the setting of the discharge port 72 and the feed port 71 in the extra-large anaerobic fermentation tank, that is, the discharge port 72 and the feed port 71 correspond one to one in the axial direction, and according to the number of the discharge ports 72 / feed ports 71, the N sector-shaped areas that divide the fermentation tank into 4 equal parts all have the feed port 71 and the discharge port 72, wherein the feed port 71 for inputting the material to be fermented and the discharge port 72 for discharging the fermentation completed material do not correspond in the axial direction, that is, the feed port 71 for inputting the material to be fermented is located in the i-th sector-shaped area 73, and the discharge port 72 for discharging the material is located in the m-th sector-shaped area 74, m≠i, and it is best that the two are located in a diagonal position, that is, they are relatively arranged. During the stirring process, the revolution range of the moving point stirring device avoids the m-th sector-shaped area 74, and only in other areas except this area along the fermentation The tank body 7 of the fermentation tank 4 reciprocates until the material is discharged from the discharge port 72 of the mth sector area 74, and then feeds from the i+1th sector area, and at the same time selects the mth sector area 74 which is not located in the same sector area as the i+1th sector area 73 for discharge. Of course, the mth sector area 74 is preferably the sector area farthest from the point where the material to be fermented is placed at this time. Similarly, feed is sequentially performed in different sector areas along the circumferential direction of the fermentation tank 4, and discharge is performed at the discharge port 72 which does not correspond to the actual feed port, preferably at a relative position for discharge, and feed and discharge are performed uninterruptedly for 24 hours, thereby achieving microbial residence time (MRT)>solid residence time (SRT)>hydraulic residence time (HRT) in the fermentation tank 4, and obtaining good anaerobic fermentation efficiency.

[0072] It should be noted that this application is attached Figure 8 73 and 74 are only schematic diagrams to illustrate a relative position of the i-th sector area and the m-th sector area, and it is not limited that the position must be the i-th sector area or the m-th sector area.

[0073] The above are only specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed by the present invention should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A dynamic point stirring device, characterized in that: include: A central column, built into the fermenter; A crossbeam, mounted on the central column and capable of performing circular motion along the body of the fermentation tank; A plurality of stirrers are suspended below the cross beam, respectively, and include a stirring shaft and stirring blades arranged on the stirring shaft, wherein the stirring shaft can drive the stirring blades to rotate, and the stirring blades can revolve around the central column along with the rotation of the cross beam; Wherein, the crossbeam is at least one of a floating crossbeam and a track crossbeam; When the cross beam is the floating cross beam, a plurality of floating boats are provided below the cross beam, and the floating boats are used to carry the cross beam on the liquid surface; When the crossbeam is a track track, the moving point stirring device also includes a rotating track adapted to the rotating track of the crossbeam, the rotating track is arranged on the inner wall of the fermentation tank, and the free end of the crossbeam can be rotatably arranged on the rotating track.

2. The dynamic point stirring device according to claim 1, characterized in that: A hydraulic rotator is installed on the central column, and the hydraulic rotator includes a hydraulic motor and a parallel gear reducer; the hydraulic motor is connected to the hydraulic station outside the fermentation tank to provide driving force for the parallel gear reducer, and the output shaft of the parallel gear reducer is a hollow rotating shaft, and the hollow rotating shaft is sleeved on the outside of the central column to provide a bearing position for connecting the crossbeam; wherein a hydraulic valve group is also provided on the hollow rotating shaft, and the hydraulic valve group is used to control the pressure, flow and direction of the hydraulic oil.

3. The dynamic point stirring device according to claim 2, characterized in that: The agitator is a hydraulic agitator. A hydraulic oil distributor connected to the hydraulic station is also provided on the central column. The hydraulic oil distributor is respectively connected to the hydraulic valve group on the hollow rotating shaft and each of the hydraulic agitators. Under the action of the hydraulic station, the hydraulic oil distributor provides hydraulic energy to the hydraulic motor and the hydraulic agitator.

4. The dynamic point stirring device according to claim 2 or 3, characterized in that: When the crossbeam is a floating crossbeam, a folding plate is provided between the crossbeam and the hollow rotating shaft, and the folding plate includes at least a first connecting plate and a second connecting plate hinged to each other, the free end of the first connecting plate is fixedly connected to the hollow rotating shaft, and the free end of the second connecting plate is hinged to the crossbeam.

5. The dynamic point stirring device according to claim 1, characterized in that: A plurality of stirring blades are arranged on the rotating shaft of each stirrer, and the stirring blades closest to the liquid surface can form vortices at the liquid surface corresponding thereto.

6. The dynamic point stirring device according to claim 2 or 3, characterized in that: When the crossbeam is the track cross track, the hollow rotating shaft is passed through the middle of the crossbeam, the crossbeam is equal in length to the diameter of the fermentation tank, and rollers are provided at both free ends of the crossbeam, through which the crossbeam is rollingly connected to the rotating track.

7. The dynamic point stirring device according to claim 2 or 3, characterized in that: There are a plurality of cross beams, each of which is connected to the hollow rotating shaft and performs circular motion as the hollow rotating shaft rotates.

8. An extra-large anaerobic fermentation tank having a dynamic point stirring device as claimed in any one of claims 1 to 5 and 7, characterized in that: It comprises a tank body, in which the dynamic point stirring device is arranged, the bottom of the tank body is provided with N evenly distributed feed ports, the top of the tank body is provided with N discharge ports corresponding to the feed ports in the axial direction, wherein N≥4, the feed ports are used to transport the materials to be fermented into the fermentation tank in turn and continuously, and the discharge ports are used to discharge the fermented materials in turn and continuously.

9. A fermentation process, characterized in that: The fermentation is carried out using the extra-large anaerobic fermentation tank as claimed in claim 8, comprising the following steps: S1. Divide the fermentation tank into N sector-shaped areas according to the number of the discharge ports / feed ports, and each sector-shaped area corresponds to one discharge port and one feed port, and the N sector-shaped areas are numbered sequentially; S2, the material to be fermented is put into the feed port of the i-th sector area, the initial value of i is 1, and the dynamic point stirring device is started and the discharge port of the m-th sector area is opened, wherein m≠i, and the stirring range of the dynamic point stirring device is controlled to avoid the m-th sector area for reciprocating stirring; S3, after stirring for 2-3 hours, let i=i+1 and execute step S2, until i is greater than N and execute step S4; S4, resetting i to the initial value, and re-performing step S2 to achieve 24-hour uninterrupted feeding and discharging.

10. The fermentation process according to claim 9, characterized in that: The mth sector area is the sector area farthest from the delivery point of the material to be fermented.

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