A biogas residue and biogas slurry mixture irrigation adjustment component

Abstract

This utility model relates to the field of agricultural irrigation equipment technology, specifically a biogas residue and biogas slurry mixture irrigation adjustment component, including a tank with a conical bottom, a stirring shaft, and a turbine impeller. The stirring shaft has a hollow interior forming a central flow channel, with its bottom extending downwards to near the bottom of the tank to form a suction port. The top surface is connected to an external negative pressure device via a rotary joint. The stirring shaft is divided into an upper section and a lower section, which are connected by a flange assembly. A hollow cavity communicating with the central flow channel is opened inside the flange assembly, and at least two sets of mounting holes communicating with the hollow cavity are opened on the circumferential surface of the flange assembly. A one-way valve is installed in the mounting hole. The valve core of the one-way valve is triggered by centrifugal force to open and allow the mixture in the hollow cavity to be thrown out. This solution, through the synergistic effect of negative pressure suction and centrifugal throwing, forces the mixture at the bottom to be transported to the upper layer, forming an axial circulation flow, effectively solving the problem of stratification at the bottom of the tank due to insufficient axial circulation of the mixture.

Description

Technical Field

[0001] This utility model relates to the field of agricultural irrigation equipment technology, specifically to an irrigation adjustment component for a mixture of biogas residue and biogas slurry. Background Technology

[0002] The biogas residue-biogas slurry mixture undergoes multiple processing steps during irrigation: First, after being discharged from the biogas plant, it enters a buffer storage unit; then, the mixture is transported to a solid-liquid separation or filtration unit to remove solid particles that may cause blockages; the filtered biogas slurry then enters an irrigation adjustment unit for concentration adjustment and homogenization. The concentration adjustment unit is responsible for diluting the biogas slurry with irrigation water according to a preset ratio, while the mixing unit ensures the diluted mixture is thoroughly mixed. Finally, the homogenized mixture is pressurized by an irrigation pump and delivered to the fields through the irrigation network.

[0003] Currently, mixing units generally use traditional turbine impellers for stirring, but this stirring and mixing scheme has obvious defects: the tangential flow accounts for more than 70%, while the axial flow is less than 10%. This flow characteristic causes the mixed liquid to easily form high-concentration stratification in the lower part of the tank, especially at and near the bottom of the tank, which essentially changes the preset mixing concentration ratio and seriously affects the irrigation effect. Utility Model Content

[0004] The purpose of this application is to provide an irrigation adjustment component for a mixture of biogas residue and biogas slurry, which generates axial flow while forming tangential flow in the tank during the mixing process, prevents high-concentration stratification at the bottom of the tank, and ensures uniform mixing, thereby solving the problems mentioned in the background art.

[0005] To achieve the above objectives, this utility model provides the following technical solution: A biogas residue and biogas slurry mixture irrigation adjustment component includes a tank with a conical bottom, a stirring shaft and a turbine impeller. The stirring shaft has a hollow interior forming a central flow channel, and its bottom surface extends downward to near the bottom of the tank to form a suction port. The top surface is connected to an external negative pressure device through a rotary joint. The stirring shaft is divided into an upper section and a lower section, which are connected by a flange assembly. A hollow cavity communicating with the central flow channel is opened inside the flange assembly. At least two sets of mounting holes communicating with the hollow cavity are opened on the circumferential surface of the flange assembly. A one-way valve is installed in the mounting hole. The valve core of the one-way valve is triggered by centrifugal force to open and allow the mixture in the hollow cavity to be thrown out.

[0006] Preferably, the one-way valve includes: The valve body has a valve cavity with a tapered surface inside; The valve core has a spherical structure and is preloaded by a spring to abut against the conical surface of the valve cavity. Preferably, the one-way valve is arranged radially along the flange assembly and is threadedly connected to the mounting hole; The check valve is provided in six groups, arranged at equal angles along the circumference of the flange assembly; The one-way valve is configured such that the total flow rate at maximum opening is less than or equal to the flow rate entering the hollow cavity.

[0007] Preferably, the one-way valve is above the maximum liquid level of the mixture that the tank can hold.

[0008] Preferably, the tank is allowed to hold the mixture above the maximum liquid level, and an inclined annular collision plate is fixedly connected along its inner wall, with the angle between the collision plate and the central axis of the tank being 30-60 degrees. The projection of the one-way valve along its own axis falls within the range of the collision plate.

[0009] Preferably, the suction port is threaded to a flared mouth, and the lower end face of the flared mouth bisects the central axis of the conical bottom of the tank.

[0010] Preferably, at least two sets of liquid outlets and two sets of liquid inlets are provided at equal angles on the side wall of the tank.

[0011] Preferably, the distance from the liquid outlet to the lower end face of the turbine impeller is equal to the distance from the impeller to the starting contraction surface of the conical bottom of the tank body; The inlet is located below the outlet and close to the starting contraction surface of the conical bottom of the tank, and the inlet and outlet are offset from each other.

[0012] Compared with the prior art, the beneficial effects of this utility model are: Compared with existing technologies, traditional mixing units mainly generate tangential flow and rely on tangential flow for mixing. However, this solution uses the synergistic effect of negative pressure suction and centrifugal ejection to force the bottom mixture to be transported to the upper layer, forming axial circulation flow, which effectively solves the problem of stratification at the bottom of the tank due to insufficient axial circulation of the mixture. On the other hand, this solution utilizes the rotation of the stirring shaft itself to throw out the mixed liquid drawn from the bottom of the tank by the central flow channel through centrifugal force, and then scatter it onto the upper liquid surface of the tank after impact. This not only realizes the axial flow of the mixed liquid in the tank, but also provides a uniform material basis for the turbine impeller to stir and mix it again. Attached Figure Description

[0013] Figure 1 A schematic diagram of the overall structure of this utility model; Figure 2 This is a schematic diagram of the structure of the present invention after removing supporting components such as the mounting plate; Figure 3 This utility model presents a schematic diagram of the internal structure of the tank after it has been cut open. Figure 4A schematic diagram showing the upper and lower sections of the stirring shaft in this invention after disassembly. Figure 5 This utility model is a structural schematic diagram showing the central flow channel, hollow cavity, and one-way valve after the stirring shaft is cut apart. Figure 6 A schematic diagram of the one-way valve in this utility model.

[0014] In the diagram: 1. Tank body; 2. Agitator shaft; 21. Upper section; 22. Lower section; 23. Bell mouth; 24. Central flow channel; 3. Turbine impeller; 4. Drive motor; 5. Transmission mechanism; 6. Connecting rod; 7. Flange assembly; 71. First flange; 72. Second flange; 73. Sealing gasket; 74. Hollow cavity; 8. One-way valve; 81. Valve body; 82. Valve core; 83. Spring; 9. Collision plate; 10. Liquid outlet; 11. Liquid outlet pipe; 12. Irrigation water pump; 13. Liquid inlet; 14. Liquid inlet pipe; 15. Preliminary mixing chamber. Detailed Implementation

[0015] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0016] This utility model provides a technical solution: In existing technologies, the biogas residue and biogas slurry mixture needs to undergo concentration adjustment and homogenization treatment before irrigation. Traditional mixing units use turbine impellers for stirring, but the tangential flow generated by the turbine impeller is dominant, resulting in insufficient axial circulation of the mixture. Due to its rheological properties, biogas residue and biogas slurry are prone to forming high-concentration stratification at the bottom of the tank, leading to uneven overall concentration of the mixture and affecting irrigation effectiveness.

[0017] To address the aforementioned problems, existing technologies have attempted to improve axial flow by modifying the impeller structure or adding auxiliary stirring devices, but these methods suffer from issues such as complex structures, difficult maintenance, and excessive energy consumption. The inventors discovered that the stratification phenomenon stems from the inability to effectively circulate the high-concentration mixture at the bottom of the tank to the upper layer. By introducing a combination of negative pressure suction and centrifugal ejection, the mixture at the bottom is forcibly transported to the upper part of the tank, forming an axial circulation that breaks down the stratification structure.

[0018] Therefore, this application proposes an irrigation adjustment component for a mixture of biogas residue and biogas slurry, such as... Figures 2 to 5As shown, it specifically includes a tank 1 with a conical bottom, a stirring shaft 2, and a turbine impeller 3. The stirring shaft 2 is connected to the tank 1 through a connecting rod 6. The stirring shaft 2 extends out of the upper part of the tank 1 and is connected to the drive motor 4 through a transmission mechanism 5, such as a belt drive mechanism. The stirring shaft 2 serves as a regular drive shaft to transmit power to the turbine impeller 3. On the other hand, it has a central flow channel 24 that runs through the bottom and top surfaces. Its bottom surface extends downward to near the bottom of the tank 1 to form a suction port. The top surface is connected to an external negative pressure device through a rotary joint. Meanwhile, the stirring shaft 2 has a segmented structure, consisting of an upper section 21 and a lower section 22, which are connected by a flange assembly 7. Specifically, the flange assembly 7 includes a first flange 71 and a second flange 72. The first flange 71 is welded to the lower end of the upper section 21 of the stirring shaft 2, and the second flange 72 is welded to the upper end of the lower section 22. A circular groove is formed on the end face of the first flange 71, and at least two sets of mounting holes connecting the circular groove are formed along the circumference of the first flange 71. A one-way valve 8 is installed in the mounting holes. The end face of the second flange 72 is a flat structure. The first flange 71 and the second flange 72 are fixedly connected by bolts, and a sealing gasket 73 is set on the mating surface to form a hollow cavity 74 with good sealing performance. The bolt fixing method facilitates the cleaning of the hollow cavity 74 during subsequent maintenance. Of course, the hollow cavity 74 can be directly formed inside the first flange 71 or the second flange 72.

[0019] like Figure 6 As shown, the specific structure of the one-way valve 8 provided in this embodiment includes a valve body 81, a valve cavity with a conical surface is opened in the valve body 81, and a valve core 82 that can move axially is provided in the valve cavity. The spherical valve core 82 abuts against the conical surface in the valve cavity by the preload of the compression spring 83, so as to realize the normally closed state of the one-way valve 8.

[0020] The external negative pressure device creates a negative pressure environment within the central flow channel 24 via a rotary joint. The higher concentration mixture at the bottom of tank 1 is drawn into the central flow channel 24 and enters the hollow cavity 74 of the flange assembly 7. When the stirring shaft 2 rotates to its normal operating speed, the flange assembly 7 rotates with the shaft, generating centrifugal force. Under the action of centrifugal force, the spherical valve core 82 detaches from the conical surface of the valve cavity, and the mixture is thrown out from the hollow cavity 74 through the one-way valve 8. The thrown-out mixture mixes with the upper mixture and is stirred and homogenized by the turbine impeller 3, forming an axial circulation flow within tank 1 to solve the problem of tank bottom stratification caused by insufficient axial circulation.

[0021] The compression spring 83 inside the check valve 8 should be selected based on the mass of the spherical valve core 82, the distance between the spherical valve core 82 and the central axis of the flange assembly 7, and the rotation speed of the stirring shaft 2 during normal operation, and ensure that the check valve 8 is fully open during normal operation.

[0022] like Figure 4 As shown, in this embodiment, the one-way valve 8 is fixedly installed in the mounting hole by a standard threaded structure, ensuring that the one-way valve 8 is firmly installed and easy to disassemble and maintain. The one-way valve 8 is arranged radially along the flange assembly 7, and six sets are arranged. The six sets of one-way valves 8 are distributed at the same interval angle on the circumferential surface of the flange assembly 7, so that the discharge path of the mixture is symmetrically distributed in the circumferential direction, avoiding too much or too little discharge of the mixture in a local area. The total flow rate of the six sets of one-way valves 8 at the maximum opening state is less than or equal to the flow rate entering the hollow cavity 74 of the flange assembly 7. Specifically, the sum of the maximum effective flow cross sections of the one-way valves 8 is less than or equal to the inner circular cross-sectional area of ​​the central flow channel 24, so as to avoid the situation where there is no mixture or the mixture is insufficient to accumulate on the side wall of the hollow cavity 74 of the flange assembly 7 during operation, resulting in the negative pressure device being connected to the outside. That is, it avoids the loss of pressure in the central flow channel 24 during operation, which would prevent the mixture at the bottom of the tank 1 from being sucked out.

[0023] In this embodiment, the setting height of the one-way valve 8, i.e. the setting height of the flange assembly 7, is higher than the maximum liquid level of the mixture that the tank 1 is allowed to load. Specifically, the height difference between the one-way valve 8 and the maximum liquid level of the mixture that the tank 1 is allowed to load is 200-500mm. The maximum liquid level of the mixture that the tank 1 is allowed to load refers to the limit height at which the mixture can be safely loaded in the tank 1, ensuring that the one-way valve 8 always operates in a gas phase environment. like Figure 3 As shown, an annular impact plate 9, which cooperates with the one-way valve 8, is provided on the inner wall of the tank 1. The impact plate 9 is also located above the liquid surface of the tank 1 at its maximum allowable loading capacity. Specifically, the impact plate 9 is a continuous annular plate structure arranged along the inner wall of the tank 1, and its surface forms a specific angle with the axis of the tank 1. The impact plate 9 can be made of metal or polymer material and fixed to the inner wall of the tank 1 by welding or bolting. This angle range is set to 30-60 degrees to minimize the risk of secondary accumulation caused by vertical liquid rebound. At the same time, the positional correspondence between the impact plate 9 and the one-way valve 8 is limited so that the axial projection of the one-way valve 8 falls completely within the range of the impact plate 9, ensuring that all ejected liquid can impact the surface of the impact plate 9. The surface of the impact plate 9 can be coated with a hydrophobic coating, such as polytetrafluoroethylene, to reduce liquid residue and enhance the impact and breaking effect.

[0024] When the stirring shaft 2 drives the flange assembly 7 and the one-way valve 8 to rotate, the mixture is drawn into the hollow cavity 74 of the flange assembly 7 through the central flow channel 24. Since the one-way valve 8 is installed above the liquid surface, the valve core 82 moves outward under the action of centrifugal force, overcoming the preload of the spring 83. The mixture is thrown into the gas phase space through the open one-way valve 8, impacts the collision plate 9 and disperses into finer droplets that fall into the mixture in the upper part of the tank 1. This not only realizes the closed-loop axial circulation of the mixture in the tank, but also disperses the mixture drawn to the bottom of the tank 1 as much as possible in the upper part of the tank 1.

[0025] like Figure 3 As shown, this embodiment also includes a flared mouth 23. The lower end face of the flared mouth 23 is located at the height bisector of the central axis of the conical bottom of the tank 1. The flared mouth 23 is detachably installed on the lower end face of the stirring shaft 2 via a threaded connection. On the one hand, it provides a normal installation and maintenance path for the turbine impeller 3, i.e., after removing the flared mouth 23, the turbine impeller 3 can be installed and removed through the lower end of the stirring shaft 2. On the other hand, compared with the straight pipe suction port, the gradually changing structure of the flared mouth 23 slows down the flow rate, avoiding the formation of excessive suction force at the lower end of the flared mouth 23 that could disrupt the axial circulation inside the tank. At the same time, the lower bottom face of the flared mouth 23 bisects the central axis of the conical bottom in the height direction. The flared mouth 23 and the conical bottom face cooperate to have a large suction range to suction the high-concentration mixture deposited in the lower part of the tank 1.

[0026] like Figure 2 and Figure 3 As shown, at least two sets of outlets 10 and two sets of inlets 13 are provided at equal angles on the side wall of the tank body 1. The outlets 10 and inlets 13 can be implemented using circular or elliptical holes. The outlets 10 are connected to an annular outlet pipe 11 surrounding the tank body 1. The outlet pipe 11 is connected to an irrigation water pump 12 and, after being pressurized by the irrigation water pump 12, is transported to the irrigation network. The mixture of irrigation water and biogas residue and biogas slurry is first transported to the preliminary mixing chamber 15. After preliminary mixing, it enters the annular inlet pipe 14 and then enters the tank body 1 through the inlet 13. In this embodiment, four sets of outlets 10 and four sets of inlets 13 are arranged at equal 90-degree angles. The four sets of outlets 10 and inlets 13 evenly distribute the suction force during discharge or the impact force during inlet, reducing the disturbance to the flow state inside the tank.

[0027] The specific location of the outlet 10 is such that the distance from the outlet 10 to the lower end face of the turbine impeller 3 is equal to the distance from the outlet 10 to the starting contraction surface of the conical bottom of the tank 1. This location area is close to achieving a dynamic balance between the axial and tangential flow of the mixture, ensuring that the outlet 10 discharges a uniformly mixed mixture. The location of the inlet 13 is such that the inlet 13 is located below the outlet 10 and close to the starting contraction surface of the conical bottom of the tank 1. Figure 3As shown, the inlet 13 is located below the outlet 10 and is staggered from the outlet 10 to prevent the new liquid from flowing directly to the outlet 10 and forming a short-circuit flow. On the other hand, it is biased towards the starting contraction surface of the conical bottom of the tank 1, and at the same time, it maintains at least half the height of the conical bottom distance from the suction port. The new liquid entering is initially mixed under the action of the axial flow in the tank. Then, the axial flow drives it to approach the suction port and is drawn into the central flow channel 24. It is then thrown out by the one-way valve 8 and mixed with the mixed liquid in the upper part. Finally, it is mixed again by the turbine impeller 3. Here, the starting contraction surface of the conical bottom is the connection surface between the conical bottom and the tank 1. The upper part is the cylindrical part of the tank 1, and the lower part is the conical part of the tank 1.

[0028] Using this utility model: Preparation: Based on the height difference between the rotary joint and flange assembly 7 and the initial liquid level in the tank 1, adjust the range of negative pressure in the central flow channel 24 to ensure that during operation, the height of the mixed liquid drawn into the central flow channel 24 is always greater than the height of the flange assembly 7 and absolutely less than the height of the rotary joint, ensuring that the mixed liquid flows normally into the hollow cavity 74 of the flange assembly 7, while preventing it from entering the negative pressure device through the rotary joint; during normal operation, control the inlet and outlet flow rates to keep the liquid level in the tank 1 within the allowable range.

[0029] Initiating the mixing process: The negative pressure device is activated and maintained, creating negative pressure within the central flow channel 24. The flared port 23 draws in the mixture from the lower part of the tank 1, filling the hollow cavity 74 of the flange assembly 7. Then, the stirring shaft 2 is activated and accelerated to its normal operating speed. The turbine impeller 3 performs stirring. Simultaneously, the spherical valve core 82 of the one-way valve 8, under the influence of centrifugal force, disengages from the conical surface of the valve cavity, leaving the one-way valve 8 fully open. The mixture within the hollow cavity 74 of the flange assembly 7 is thrown out by the one-way valve 8, shatters upon impact with the collision plate 9, and scatters onto the liquid surface at the top of the tank 1. It is then further mixed by the turbine impeller 3. The suction port continuously draws in the mixture from the bottom, and the one-way valve 8 continuously throws out the mixture drawn into the hollow cavity 74 of the flange assembly 7, promoting a closed-loop axial circulation within the tank 1 and preventing the formation of high-concentration stratification at the bottom of the tank 1, especially at the conical bottom.

[0030] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A biogas residue and biogas slurry mixture irrigation adjustment assembly, comprising a tank (1) with a conical bottom, a stirring shaft (2), and a turbine impeller (3), characterized in that, The stirring shaft (2) has a hollow interior forming a central flow channel (24), and its bottom surface extends downward to near the bottom of the tank (1) to form a suction port. The top surface is connected to an external negative pressure device through a rotary joint. The stirring shaft (2) is divided into an upper section (21) and a lower section (22), and the two are connected by a flange assembly (7). The flange assembly (7) has a hollow cavity (74) that communicates with the central flow channel (24). At least two sets of mounting holes communicating with the hollow cavity (74) are opened on the circumferential surface of the flange assembly (7). A one-way valve (8) is installed in the mounting hole. The valve core (82) of the one-way valve (8) is triggered by centrifugal force to open and allow the mixture in the hollow cavity (74) to be thrown out.

2. The biogas residue and biogas liquid mixture irrigation adjusting assembly according to claim 1, wherein, The one-way valve (8) includes: The valve body (81) has a valve cavity with a conical surface inside; The valve core (82) has a spherical structure and is pre-tightened by a spring (83) against the conical surface of the valve cavity.

3. The biogas residue and biogas liquid mixture irrigation adjusting assembly according to claim 2, characterized in that, The one-way valve (8) is arranged radially along the flange assembly (7) and is threadedly connected to the mounting hole; The one-way valve (8) is provided in six groups, arranged at equal angles along the circumferential surface of the flange assembly (7); The one-way valve (8) is configured such that the total flow rate in the maximum opening state is less than or equal to the flow rate entering the hollow cavity (74).

4. The biogas residue and biogas slurry mixture irrigation adjustment component according to claim 2, characterized in that, The one-way valve (8) is higher than the tank (1) to allow the maximum liquid level of the mixture to be loaded.

5. The biogas residue and biogas liquid mixture irrigation adjusting assembly according to claim 4, characterized in that, The tank (1) is allowed to hold the mixture above the maximum liquid level. An inclined annular collision plate (9) is fixedly connected along its inner wall. The angle between the collision plate (9) and the central axis of the tank (1) is 30-60 degrees. The projection of the one-way valve (8) along its own axis falls on the collision plate (9).

6. The biogas residue and biogas liquid mixture irrigation adjusting assembly according to claim 1, wherein, The suction port is threadedly connected to the flared mouth (23), and the lower end face of the flared mouth (23) bisects the central axis of the conical bottom of the tank body (1).

7. The biogas residue and biogas liquid mixture irrigation adjusting assembly according to claim 6, characterized in that, The tank (1) has at least two sets of liquid outlets (10) and two sets of liquid inlets (13) at equal angles on its side wall.

8. The biogas residue and biogas liquid mixture irrigation adjusting assembly according to claim 7, characterized in that, The distance from the outlet (10) to the lower end face of the turbine impeller (3) is equal to the distance from it to the starting contraction surface of the conical bottom of the tank (1); The inlet (13) is located below the outlet (10) and close to the starting contraction surface of the conical bottom of the tank (1). The inlet (13) and the outlet (10) are offset from each other.

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