Open type raceway pond for enhancing liquid mixing by utilizing wind energy

Abstract

The utility model discloses an open type raceway pond for strengthening liquid mixing by utilizing wind energy, which is characterized in that a pneumatic mixer is arranged in at least one flow channel, the pneumatic mixer comprises a rotating shaft, and a bearing is sleeved on the rotating shaft; one end of the rotating shaft is fixedly connected with the pneumatic blade, and the other end is fixedly connected with the stirring blade; the pneumatic mixer further comprises a supporting frame, the bearing is fixed to the supporting frame, and the bottom of the supporting frame is fixedly connected to the pool bottom of the open type raceway pool body. The pneumatic blade is located above the bearing, the stirring blade is located below the bearing, and a gap is reserved between the stirring blade and the pool bottom of the open type raceway pool body. According to the utility model, the pneumatic mixer is arranged in the runner of the open type raceway pond, so that the full mixing of algae liquid in the raceway pond is promoted on the premise of not increasing the energy consumption, especially the mixing in the vertical direction is realized, and the illumination of algae cells is facilitated.

Description

Technical Field

[0001] The utility model belongs to the field of microalgae cultivation, and in particular relates to an open runway pool which utilizes wind energy to enhance liquid mixing. Background Art

[0002] Microalgae convert solar energy into chemical energy through photosynthesis and store it in cells to form biomass, which can be used as food, nutritional supplements, aquatic bait, etc., and can be further processed into biofuel. The large-scale cultivation of microalgae can be divided into closed photobioreactors and open raceway pools. Among them, the raceway pool has been widely used in industrial production due to its low construction and operation and maintenance costs and simple technology.

[0003] At present, the light energy conversion rate of microalgae photosynthesis is about 1%, which is far lower than the theoretical conversion rate of 12%. The main reason is that the mixing of the microalgae culture solution in the raceway pool is driven by the agitator and the mixing is insufficient, which is a naturally formed turbulence. Especially at a position far away from the agitator, it is basically close to laminar flow, and the algae cells are deposited at the bottom. As a result, the light on the surface of the algae liquid is strong, but there are few cells, and the light in the lower layer of the algae liquid is weak, but there are many cells, and the overall light energy conversion efficiency of the reactor is reduced.

[0004] If the algae cells can shuttle back and forth between the surface and the lower layer of the raceway pool, more cells can be exposed to light and the photons irradiated on the culture medium can be fully utilized. Therefore, the full mixing of the culture medium in the raceway pool, especially the mixing in the vertical direction, is crucial to increasing the overall yield of microalgae. Utility Model Content

[0005] In view of the deficiencies in the prior art, the utility model designs an open runway pool that utilizes wind energy to enhance liquid mixing, thereby solving the problem of uneven mixing of algae liquid in the pool, being beneficial to sufficient mixing of the algae liquid in the runway pool, and further increasing the yield of microalgae.

[0006] The specific contents are as follows:

[0007] The purpose of the present invention is to provide an open runway pool for enhancing liquid mixing by using wind energy, comprising an open runway pool body, wherein a flow partition wall is arranged in the open runway pool body, wherein the flow partition wall divides the open runway pool body into two flow channels connected to each other at both ends; at least one flow channel is provided with a stirring paddle for driving the algae liquid to flow, and the difference between the present invention and the prior art is that:

[0008] A pneumatic mixer is arranged in at least one flow channel, and the pneumatic mixer comprises a rotating shaft, and a bearing is sleeved on the rotating shaft; one end of the rotating shaft is fixedly connected to a pneumatic blade, and the other end is fixedly connected to a stirring blade;

[0009] The pneumatic mixer also includes a support frame, the bearing is fixed to the support frame, and the bottom of the support frame is fixedly connected to the bottom of the open runway pool body;

[0010] The pneumatic blades are located above the bearings, the stirring blades are located below the bearings, and a gap is left between the stirring blades and the bottom of the open track pool body.

[0011] When using the above-mentioned open raceway pool, the algae liquid circulates under the drive of the stirring paddle. The liquid surface of the algae liquid must be below the wind blades and not above the stirring blades. The open raceway pool is usually in an open-air environment. The wind blades start to rotate after being driven by wind, and drive the stirring blades under the liquid surface to rotate, thereby strengthening the mixing of the culture liquid, causing the algae cells to flip up and down, breaking the laminar flow in the raceway pool, and promoting the full mixing of the algae liquid in the raceway pool. The support frame plays the role of stabilizing the mixer.

[0012] Furthermore, it is preferred to set one or more pneumatic mixers in each flow channel of the open runway pool body. The pneumatic mixer is preferably installed away from the stirring paddle, and can be in an area with poor mixing. When a pneumatic mixer is set in each flow channel, it is preferably set in the middle of the total length of each flow channel.

[0013] Furthermore, the pneumatic blades are multiple and evenly arranged around the rotating shaft; the pneumatic blades are hollow hemispherical and fixed to the rotating shaft via connecting rods. The concave surface of each hollow hemispherical blade faces the horizontal direction and is arranged in the same clockwise direction around the rotating shaft, and moves in a circular motion after being driven by wind.

[0014] Wherein, the diameter of the hollow hemispherical blade is preferably 5 to 30 cm.

[0015] In each pneumatic mixer, the number of pneumatic blades is preferably 3 or 4.

[0016] Wherein, the wind blades are preferably made of plastic or carbon fiber and are light in weight.

[0017] Furthermore, the stirring blades are preferably 2 to 10 cm away from the bottom of the open track pool body.

[0018] Wherein, the shape of the stirring blade is preferably flat blade, curved blade or butterfly shape.

[0019] Wherein, the rotation diameter of the stirring blade is preferably smaller than the rotation diameter of the pneumatic blade.

[0020] In each pneumatic mixer, the number of stirring blades is preferably 2, 3, 4 or 6.

[0021] Wherein, the stirring blade is preferably made of corrosion-resistant stainless steel or organic glass.

[0022] Furthermore, the support frame is preferably a tripod, and the support frame is preferably made of stainless steel.

[0023] Furthermore, a carbon replenishment circulation barrel is provided at one end of the open raceway pool body. The carbon replenishment circulation barrel is preferably separated from the open raceway pool body, and an aeration device is provided at the bottom of the barrel. The culture fluid enters the circulation barrel from one flow channel of the raceway pool, and returns to another flow channel after carbon replenishment.

[0024] The carbon replenishment process is controlled by the pH value of the culture solution. A control point is set according to the optimal growth pH value of the cultured microalgae. When the actual pH value of the culture solution is higher than the set pH value, the circulation of the liquid is started and carbon replenishment is started at the same time. When the actual pH value of the culture solution is lower than the set pH value, the circulation of the liquid is stopped and carbon replenishment is stopped at the same time. The device improves the absorption efficiency of carbon dioxide in the original raceway pond cultivation process and saves the carbon source cost of microalgae cultivation.

[0025] The beneficial effects of the utility model are as follows:

[0026] The utility model arranges a pneumatic mixer in the flow channel of the open runway pool, which promotes the full mixing of the algae liquid in the runway pool without increasing energy consumption, especially realizes the mixing in the up and down directions, which is beneficial for the algae cells to receive light, can give full play to the photosynthesis of the algae cells, improves the light energy utilization rate of large-scale cultivation of microalgae, and increases the yield per unit illumination area. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 is a schematic diagram of the main view of a pneumatic mixer;

[0028] Figure 2 is a top view schematic diagram of a pneumatic mixer;

[0029] Figure 3 is a schematic diagram of an open runway pool in Example 1;

[0030] Figure 4 is a schematic diagram of an open runway pool in Example 2;

[0031] In the figure: 1. Open runway pool body; 2. Flow separation wall; 3. Stirring paddle; 4. Pneumatic mixer; 4-1. Pneumatic blade; 4-2. Stirring blade; 4-3. Bearing; 4-4. Support frame; 5. Carbon replenishment circulation barrel. DETAILED DESCRIPTION

[0032] The principles and features of the present invention are described below in conjunction with examples. The examples are only used to explain the present invention and are not used to limit the scope of the present invention.

[0033] Example 1

[0034] An open raceway pool that uses wind energy to enhance liquid mixing, such as Figures 1 to 3 As shown, it comprises an open runway pool body 1, wherein a flow partition wall 2 is arranged in the open runway pool body 1, wherein the flow partition wall 2 divides the runway pool into two flow channels connected to each other at both ends; a stirring paddle 3 for driving the algae liquid to flow is arranged at one end of one of the flow channels, and the stirring paddle 3 is driven by a motor; the size of the open runway pool body 1 is 60 meters long and 3.4 meters wide, the pool wall height is 0.5 meters, and the width of the single flow channel is 1.7 meters;

[0035] Each flow channel is provided with a pneumatic mixer 4, which is located in the middle of the total length of the flow channel; the pneumatic mixer 4 comprises a rotating shaft, on which a bearing 4-3 is sleeved; one end of the rotating shaft is fixedly connected to a pneumatic blade 4-1, and the other end is fixedly connected to a stirring blade 4-2;

[0036] Each pneumatic mixer 4 has 4 pneumatic blades 4-1, which are evenly arranged around the rotating shaft; the pneumatic blades 4-1 are hollow hemispherical, and are fixed to the rotating shaft by connecting rods; the concave surface of each pneumatic blade 4-1 faces the horizontal direction, and is arranged in the same clockwise direction around the rotating shaft, and moves in a circular motion after being driven by wind; the pneumatic blades 4-1 are made of polyethylene plastic, the spherical diameter is 10 cm, and the diameter of the circular motion is 1 meter;

[0037] The number of stirring blades 4-2 of each pneumatic mixer 4 is 3, the shape is flat blade type, the material is organic glass, and the diameter of the circular motion is 0.5 meters;

[0038] The pneumatic mixer 4 also includes a support frame 4-4, the bearing 4-3 is fixed to the support frame 4-4, and the bottom of the support frame 4-4 is fixedly connected to the bottom of the open runway pool body 1; the support frame 4-4 is a tripod made of stainless steel;

[0039] The pneumatic blade 4-1 is located above the bearing 4-3, the stirring blade 4-2 is located below the bearing 4-3, and the distance between the stirring blade 4-2 and the bottom of the open track pool body 1 is 5 cm;

[0040] A carbon replenishment circulation barrel 5 is also provided at one end of the open raceway pool body 1, and an aeration device is provided at the bottom of the carbon replenishment circulation barrel 5. The culture fluid enters the carbon replenishment circulation barrel 5 from one flow channel of the raceway pool and returns to another flow channel after carbon replenishment.

[0041] The above-mentioned open runway pool is arranged in an open-air environment, and natural light is used for cell growth. When using the above-mentioned open runway pool, start the stirring paddle 3 so that the flow rate of the culture solution is 30cm / s. Spirulina is inoculated in the runway pool with an inoculation density of 0.2g / L and a liquid layer depth of 30cm. The most suitable pH range for culture is set to 9.5, that is, when the pH value is higher than 9.5, the carbon replenishment circulation barrel 5 starts to replenish CO2, and when it is lower than 9.5, the replenishment of CO2 is stopped. The pneumatic mixer 4 is driven by natural wind. The continuous cycle culture is carried out for 10 days, and evaporated water is replenished every day. At the end of the culture, the cell density of Spirulina is 0.6g / L; the average growth rate is calculated to be 12g / m 2 / d.

[0042] Comparative Example 1

[0043] Referring to Example 1, the difference from Example 1 is that no pneumatic mixer 4 is provided in the flow channel. The remaining technical features are the same as those of Example 1.

[0044] When Spirulina was cultivated under the same conditions as in Example 1, the average growth rate after the same cultivation time (10 days) was only 10 g / m 2 This result shows that the pneumatic mixer strengthens the mixing of liquid, promotes the frequency of microalgae cells shuttling between the light and dark interface, and improves the growth efficiency of microalgae to a certain extent.

[0045] Example 2

[0046] An open raceway pool that uses wind energy to enhance liquid mixing, such as Figure 1 , 2 , 4, with reference to Example 1, the difference from Example 1 is that:

[0047] The number of pneumatic mixers 4 in the open runway pool body 1 is 4, and the arrangement method is to evenly arrange them according to the length of the circulation channel of the runway pool, with 2 in each channel;

[0048] The number of stirring blades 4 - 2 of each pneumatic mixer 4 is 6, and the stirring blades 4 - 2 are butterfly-shaped.

[0049] The remaining technical features are the same as those of Example 1.

[0050] The above-mentioned open runway pool is arranged in an open-air environment, and natural light is used for cell growth. When using the above-mentioned open runway pool, start the stirring paddle 3 so that the flow rate of the culture solution is 30cm / s. Spirulina is inoculated in the runway pool with an inoculation density of 0.2g / L and a liquid layer depth of 30cm. The most suitable pH range for culture is set to 9.5, that is, when the pH value is higher than 9.5, the carbon replenishment circulation barrel 5 starts to replenish CO2, and when it is lower than 9.5, the replenishment of CO2 is stopped. The pneumatic mixer 4 is driven by natural wind. The continuous cycle culture is carried out for 10 days, and evaporated water is replenished every day. At the end of the culture, the cell density of Spirulina is 0.7g / L; the average growth rate is calculated to be 15g / m 2 / d.

[0051] Comparative Example 2

[0052] Referring to Example 2, the difference from Example 2 is that no pneumatic mixer 4 is provided in the flow channel. The remaining technical features are the same as those of Example 1.

[0053] When Spirulina was cultivated under the same conditions as in Example 2, the average growth rate after the same cultivation time (10 days) was only 12 g / m 2 This result shows that the pneumatic mixer strengthens the mixing intensity of the liquid, promotes the photosynthesis efficiency of microalgae cells, and greatly increases the biomass accumulation of microalgae.

[0054] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. An open raceway pool for enhancing liquid mixing by using wind energy, comprising an open raceway pool body (1), wherein a flow partition wall (2) is provided in the open raceway pool body (1), wherein the flow partition wall (2) divides the open raceway pool body (1) into two flow channels connected to each other at both ends; at least one flow channel is provided with a stirring paddle (3) for driving the algae liquid to flow, characterized in that: A pneumatic mixer (4) is arranged in at least one flow channel, the pneumatic mixer (4) comprising a rotating shaft, on which a bearing (4-3) is sleeved; one end of the rotating shaft is fixedly connected to a pneumatic blade (4-1), and the other end is fixedly connected to a stirring blade (4-2); The pneumatic mixer (4) further comprises a support frame (4-4), the bearing (4-3) is fixed to the support frame (4-4), and the bottom of the support frame (4-4) is fixedly connected to the bottom of the open runway pool body (1); The pneumatic blades (4-1) are located above the bearings (4-3), the stirring blades (4-2) are located below the bearings (4-3), and a gap is left between the stirring blades (4-2) and the bottom of the open track pool body (1).

2. The open track pool according to claim 1, characterized in that: One or more pneumatic mixers (4) are arranged in each flow channel of the open-type runway pool body (1).

3. The open track pool according to claim 1, characterized in that: The pneumatic blades (4-1) are multiple and evenly arranged around the rotating shaft; the pneumatic blades (4-1) are hollow hemispherical and are fixed to the rotating shaft via connecting rods.

4. The open track pool according to claim 3, characterized in that: The diameter of the hollow hemispherical blade is 5 to 30 cm.

5. The open track pool according to claim 3, characterized in that: The number of the wind-driven blades (4-1) is 3 or 4.

6. The open track pool according to claim 1, characterized in that: The stirring blades are 2 to 10 cm away from the bottom of the open track pool body (1).

7. The open track pool according to claim 1, characterized in that: The stirring blade is in the shape of a flat blade, a curved blade or a butterfly shape.

8. The open track pool according to claim 1, characterized in that: The rotation diameter of the stirring blade is smaller than the rotation diameter of the pneumatic blade.

9. The open track pool according to claim 1, characterized in that: The supporting frame (4-4) is a tripod.

10. The open track pool according to claim 1, characterized in that: A carbon replenishment circulation barrel (5) is provided at one end of the open runway pool body (1).

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