Algae cultivation device

Abstract

To provide an algae growth device that can prevent the growth of algae from being hindered by the diatoms that have been mixed in device and attached to the algae.SOLUTION: An algae growth device 1 has a growth tank 10 for growing algae with growth water, and a UV sterilizer 2 for exposing algae to the air out of the growth water and irradiating the dried algae with ultraviolet rays.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to an algae cultivation device. [Background technology]

[0002] There are known algae cultivation devices for cultivating algae such as laver, wakame, and kelp on land. The algae cultivation device in the following Patent Document 1 includes a gas dissolving unit capable of generating a solution in which carbon dioxide is dissolved in a liquid, an algae tank capable of containing the solution and the algae contained in the solution, and a light emitter capable of emitting light toward the inside of the algae tank in which the solution and the algae are contained.

[0003] In addition, the marine plant cultivation system of Patent Document 2 below includes a pumping flow path that pumps up saltwater from at least one water source of seabed groundwater and deep ocean water, a gas mixing unit that mixes saltwater with gas containing carbon dioxide to produce mixed saltwater, a growth tank that stores the mixed saltwater and can accommodate algae, and a light irradiation unit that irradiates light into the growth tank.

[0004] The growth tank in Patent Document 2 below has multiple growth chambers connected in the order of increasing volume from the upstream side to the downstream side. Between adjacent growth chambers there are communication ports that can be opened and closed to allow liquid to pass through, and marine organisms grown in the upstream growth chamber are introduced to the adjacent downstream growth chamber for growth according to the growth stage of the marine organisms. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2020-174607 A [Patent Document 2] JP 2019-50782 A Summary of the Invention [Problem to be solved by the invention]

[0006] One of the issues with the above-mentioned algae cultivation device is how to prevent diatoms from being mixed in. Diatoms are widely distributed in both freshwater and seawater, and can also be mixed in from the air, making them difficult to remove completely. Diatoms attach to the cultivation tank and algae, consume carbon dioxide added to the cultivation water, and repeatedly undergo photosynthesis, growing faster than the target algae. Diatoms that grow in this way block the light absorption of the target algae, reducing the efficiency of photosynthesis of the algae, and as a result, inhibiting the growth of the algae.

[0007] The present invention has been made in consideration of the above problems, and aims to provide an algae cultivation apparatus that can suppress the inhibition of algae growth caused by the inclusion and attachment of diatoms. [Means for solving the problem]

[0008] An algae cultivation apparatus according to one embodiment of the present invention comprises a cultivation tank in which algae are cultivated in cultivation water, and an ultraviolet sterilization device which dries the algae out of the cultivation water and irradiates them with ultraviolet light.

[0009] In addition, in an algae cultivation device according to one embodiment of the present invention, the ultraviolet sterilization device may include an ultraviolet sterilization tank that receives the algae and the cultivation water from the cultivation tank, a mesh member provided inside the ultraviolet sterilization tank that separates the cultivation water from the algae, and an ultraviolet light source that irradiates ultraviolet light onto the algae supported by the mesh member.

[0010] In addition, in an algae cultivation apparatus according to one aspect of the present invention, the ultraviolet sterilization device may be provided with a cultivation water transfer device that lowers the water level of the cultivation water in the ultraviolet sterilization tank below the mesh member.

[0011] In addition, in an algae cultivation apparatus according to one embodiment of the present invention, the cultivation water transfer device may return the cultivation water after irradiation with ultraviolet rays, and raise the water level of the cultivation water in the ultraviolet sterilization tank above the mesh member.

[0012] In addition, in an algae cultivation apparatus according to one aspect of the present invention, the ultraviolet sterilization tank may be provided with a lower water level gauge that detects when the water level of the cultivation water is lower than the mesh member.

[0013] In addition, in an algae cultivation apparatus according to one aspect of the present invention, the ultraviolet sterilization tank may be provided with an upper water level gauge that detects when the water level of the cultivation water is higher than the mesh member.

[0014] In addition, in an algae cultivation apparatus according to one aspect of the present invention, the ultraviolet sterilization device may be provided with a moving device for moving the mesh member closer to or away from the ultraviolet light source.

[0015] In addition, in the algae cultivation apparatus according to one aspect of the present invention, a plurality of the cultivation tanks may be provided, and one ultraviolet sterilization device may be provided for each of the plurality of cultivation tanks.

[0016] In addition, in an algae cultivation apparatus according to one embodiment of the present invention, the ultraviolet sterilization device may include a drying device that dries the algae from the cultivation water and transports them, and an ultraviolet light source that irradiates ultraviolet rays onto the algae being transported by the drying device.

[0017] In addition, in an algae cultivation apparatus according to one embodiment of the present invention, the ultraviolet sterilization device may be provided with a blower device that blows air to the algae upstream of the ultraviolet light source on the transport path of the drying device.

[0018] In addition, in an algae cultivation apparatus according to one aspect of the present invention, the drying out device may include a conveyor device for carrying and transporting the algae, and a water receiving tank arranged below the conveyor device.

[0019] In addition, in the algae cultivation apparatus according to one aspect of the present invention, one ultraviolet sterilization device may be provided for each cultivation tank.

[0020] In addition, in the algae cultivation apparatus according to one aspect of the present invention, the ultraviolet sterilization device may include an ultraviolet light emitting diode that irradiates ultraviolet light. Effect of the Invention

[0021] According to one aspect of the present invention described above, an algae cultivation apparatus can be provided that can suppress the inhibition of algae growth caused by the inclusion and attachment of diatoms. [Brief description of the drawings]

[0022] [Figure 1] FIG. 1 is a configuration diagram of an algae cultivation apparatus according to a first embodiment. [Diagram 2] FIG. 2 is a configuration diagram of an ultraviolet sterilization tank according to the first embodiment. [Diagram 3] 4 is a flowchart illustrating the process of transferring algae from a first cultivation tank to a second cultivation tank in the algae cultivation apparatus according to the first embodiment. [Figure 4] 4 is a flow chart illustrating the process of transferring algae from a first cultivation tank to an ultraviolet sterilization tank in the algae cultivation apparatus according to the first embodiment. [Diagram 5] 4 is a flowchart illustrating an algae sterilization process in the algae cultivation apparatus according to the first embodiment. [Figure 6] 4 is a flowchart illustrating an algae sterilization process in the algae cultivation apparatus according to the first embodiment. [Figure 7] FIG. 11 is a configuration diagram of an algae cultivation apparatus according to a second embodiment. [Figure 8] 13 is a flowchart illustrating an algae sterilization process in an algae cultivation apparatus according to a second embodiment. [Figure 9] FIG. 11 is a configuration diagram of an algae cultivation apparatus according to a third embodiment. [Figure 10] FIG. 11 is an external view of an algae cultivation apparatus according to a third embodiment. [Figure 11] FIG. 11 is an external view of a cultivation tank according to a third embodiment. [Figure 12] FIG. 11 is an external view of a drying device according to a third embodiment. [Figure 13]FIG. 11 is an external view of a drying processing device according to a third embodiment. [Figure 14] 13 is a flowchart showing the process of transferring algae from the cultivation tank of an algae cultivation apparatus according to a third embodiment. [Figure 15] 13 is a flow chart showing the process of transferring algae in the drying device of the algae cultivation apparatus according to the third embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0023] An algae cultivation apparatus according to an embodiment of the present invention will now be described in detail with reference to the drawings. First, an overview of the embodiment of the present invention will be described, and then the details of the embodiment of the present invention will be described.

[0024] 〔overview〕 In algae cultivation devices that cultivate algae on land, it is important to understand the degree of algae growth, eliminate diatoms and other organisms that inhibit algae growth, and manage the environment necessary for algae growth, specifically, water quality (nutrients, dissolved carbon dioxide), water temperature, and light intensity.

[0025] The algae cultivation device shown in Patent Document 1 uses carbon dioxide (CO 2 It is made up of a gas dissolving section (a gas dissolving unit) and an algae cultivation tank, lighting, a circulation pump, a supply unit for the components necessary for cultivation such as nutrients. There is also a pipe that sends water from the gas dissolving unit to the cultivation tank, and the cultivation water is adjusted in the gas dissolving unit and the supply unit, and is sent and circulated to the algae cultivation tank to cultivate the seaweed, which is the target of cultivation.

[0026] The marine plant cultivation system shown in Patent Document 2 has separate cultivation chambers according to the cultivation stage of the algae. In this cultivation system, cultivation water is supplied to each cultivation chamber through individual pipes, and the water is moved to a larger cultivation chamber according to the cultivation stage of the algae. With this configuration, since the cultivation water is independent for each cultivation chamber, the composition of the cultivation water can be changed depending on the cultivation stage, and the cultivation components can be efficiently supplied to the algae.

[0027] One of the challenges in coastal and land-based aquaculture as described above is how to prevent diatom contamination. Diatoms are widely distributed in both freshwater and seawater, and can also be mixed in from the air, making them difficult to completely remove. In algae cultivation, suppressing the occurrence of diatoms is a major challenge. This is because diatoms attach to the cultivation tank and algae, consume carbon dioxide added to the cultivation water, and repeatedly photosynthesize, growing faster than the target algae. These proliferating diatoms block the light absorption of the target algae, reducing the efficiency of the photosynthetic reaction of the algae, and as a result, inhibiting their growth.

[0028] In an embodiment of the present invention, an algae cultivation device mechanically simulates the natural process of algae emerging from the sea surface at low tide, etc. Specifically, the water level of the cultivation water is controlled during algae cultivation, the algae are lifted out of the cultivation water, separated from the cultivation water, exposed to ultraviolet light for a certain period of time, and diatoms attached to the surface of the algae are removed. This makes it possible to suppress the contamination and adhesion of diatoms, which can hinder the growth of the algae.

[0029] [First embodiment] FIG. 1 is a configuration diagram of an algae cultivation apparatus 1 according to a first embodiment. As shown in FIG. 1, the algae cultivation apparatus 1 comprises a plurality of cultivation tanks 10, an ultraviolet sterilization tank 20, a waste tank 30, an algae transfer device 40, a photography device 50, and a control device 60.

[0030] The cultivation tank 10 contains algae and cultivation water for cultivating the algae. The algae may be, for example, nori seaweed, wakame seaweed, or kombu seaweed. The cultivation water may be, for example, salt water containing nutrients and carbon dioxide dissolved in it. The cultivation tank 10 is provided with a water flow generator including a pump that creates a flow in the cultivation water in the tank, and a light irradiation device including an LED (light emitting diode) that irradiates the tank with light for the algae to photosynthesize.

[0031] The algae cultivation apparatus 1 is equipped with a first cultivation tank 11, a second cultivation tank 12, and a third cultivation tank 13 as cultivation tanks 10. The second cultivation tank 12 has a larger volume than the first cultivation tank 11. Furthermore, the third cultivation tank 13 has a larger volume than the second cultivation tank 12. For example, the second cultivation tank 12 may have twice the volume of the first cultivation tank 11. Furthermore, the third cultivation tank 13 may have four times the volume of the first cultivation tank 11 (twice the volume of the second cultivation tank 12). Note that, although the algae cultivation apparatus 1 of this embodiment is equipped with three cultivation tanks 10, the number of stages is arbitrary, and it may be equipped with two stages or four or more stages of cultivation tanks 10.

[0032] The algae transfer device 40 includes a first transfer line 41 that transfers algae from the first cultivation tank 11 to the second cultivation tank 12. The first transfer line 41 is a piping section that connects the first cultivation tank 11 and the second cultivation tank 12, and an opening / closing valve 41a is provided in this piping section. The algae transfer device 40 also includes a second transfer line 42 that transfers algae from the second cultivation tank 12 to the third cultivation tank 13. The second transfer line 42 is a piping section that connects the second cultivation tank 12 and the third cultivation tank 13, and an opening / closing valve 42a is provided in this piping section.

[0033] The algae transfer device 40 also includes a third transfer line 43 that transfers algae from the first cultivation tank 11 to the ultraviolet sterilization tank 20. The third transfer line 43 is a piping section that connects the first cultivation tank 11 and the ultraviolet sterilization tank 20, and this piping section is provided with an open / close valve 43a and a pump 43b. The algae transfer device 40 also includes a fourth transfer line 44 that transfers (returns) algae from the ultraviolet sterilization tank 20 to the first cultivation tank 11. The fourth transfer line 44 is a piping section that connects the ultraviolet sterilization tank 20 and the first cultivation tank 11, and this piping section is provided with an open / close valve 44a.

[0034] The algae transfer device 40 also includes a fifth transfer line 45 that transfers algae from the second cultivation tank 12 to the ultraviolet sterilization tank 20. The fifth transfer line 45 is a piping section that connects the second cultivation tank 12 and the ultraviolet sterilization tank 20, and this piping section is provided with an open / close valve 45a and a pump 45b. The algae transfer device 40 also includes a sixth transfer line 46 that transfers (returns) algae from the ultraviolet sterilization tank 20 to the second cultivation tank 12. The sixth transfer line 46 is a piping section that connects the ultraviolet sterilization tank 20 and the second cultivation tank 12, and this piping section is provided with an open / close valve 46a.

[0035] The algae transfer device 40 also includes a seventh transfer line 47 that transfers algae from the third cultivation tank 13 to the ultraviolet sterilization tank 20. The seventh transfer line 47 is a piping section that connects the third cultivation tank 13 and the ultraviolet sterilization tank 20, and this piping section is provided with an open / close valve 47a and a pump 47b. The algae transfer device 40 also includes an eighth transfer line 48 that transfers (returns) algae from the ultraviolet sterilization tank 20 to the third cultivation tank 13. The eighth transfer line 48 is a piping section that connects the ultraviolet sterilization tank 20 and the third cultivation tank 13, and this piping section is provided with an open / close valve 48a.

[0036] The algae transfer device 40 also includes a ninth transfer line 49 that transfers algae from the ultraviolet sterilization tank 20 to the waste tank 30. The ninth transfer line 49 is a piping section that connects between the ultraviolet sterilization tank 20 and the waste tank 30, and this piping section is provided with an opening / closing valve 49a. The above-mentioned opening and closing valves 41a to 49a are motorized valves, solenoid valves, or the like, and are adapted to operate under the control of the control device 60 together with the pumps 43b, 45b, and 48b.

[0037] In this embodiment, the second cultivation tank 12 is provided at a lower position than the first cultivation tank 11, the third cultivation tank 13 is provided at a lower position than the second cultivation tank 12, the ultraviolet sterilization tank 20 is provided at a higher position than the first cultivation tank 11, the second cultivation tank 12, and the third cultivation tank 13, and the waste tank 30 is provided at a lower position than the ultraviolet sterilization tank 20. In this case, the pumps 43b, 45b, and 48b only need to be operated when pumping the algae and cultivation water from the first cultivation tank 11, the second cultivation tank 12, and the third cultivation tank 13 to the ultraviolet sterilization tank 20, and the transfer between the other tanks can be performed by simply opening the opening and closing valves 41a to 49a using the head difference. In cases where the tanks are provided at the same height, a pump may be provided on each of the transfer lines 41 to 49.

[0038] Fig. 2 is a configuration diagram of the ultraviolet sterilization tank 20 according to the first embodiment. Note that, although Fig. 2 shows the connection relationship between the ultraviolet sterilization tank 20 and the first cultivation tank 11, the connection relationship between the ultraviolet sterilization tank 20 and the second cultivation tank 12, and the connection relationship between the ultraviolet sterilization tank 20 and the third cultivation tank 13 are also configured similarly. As shown in FIG. 2, the ultraviolet sterilization tank 20 includes a net member 21, an ultraviolet light source 22, a cultivation water transfer device 23, a lower water level gauge 24, an upper water level gauge 25, and a moving device 26.

[0039] The ultraviolet sterilization tank 20, net member 21, ultraviolet light source 22, cultivation water transfer device 23, lower water level gauge 24, upper water level gauge 25, and moving device 26 constitute an ultraviolet sterilization device 2 that dries out the algae from the cultivation water and irradiates them with ultraviolet rays. The ultraviolet sterilization device 2 simulates the natural process of seawater ebb and flow and the drying out process caused by ultraviolet rays from sunlight, and prevents the growth of algae from being inhibited by the attachment of diatoms through irradiation with ultraviolet rays.

[0040] The interior of the ultraviolet sterilization tank 20 is divided into an upper space and a lower space by the mesh member 21. The above-mentioned third transfer line 43, fourth transfer line 44, and ninth transfer line 49 are connected to the upper space of the ultraviolet sterilization tank 20. The mesh member 21 has mesh sizes smaller than the average size of young algae, and captures the algae received from the third transfer line 43 with the mesh and separates the cultivation water (indicated by reference symbol 3 in FIG. 2) from the algae.

[0041] The ultraviolet light source 22 irradiates ultraviolet light onto the algae supported by the net member 21. The ultraviolet light source 22 includes, for example, an ultraviolet light-emitting diode capable of irradiating ultraviolet light equivalent to UV-B (ultraviolet B radiation) having a wavelength of 280 to 320 nm. The ultraviolet light source 22 irradiates the algae supported by the net member 21 with ultraviolet light for a certain period of time, thereby inactivating diatoms and the like attached to the algae.

[0042] The moving device 26 includes a guide and an actuator for moving the net member 21 up and down, and adjusts the amount of ultraviolet light hitting the algae by moving the net member 21 closer to or farther away from the ultraviolet light source 22. The cultivation water transfer device 23 includes a water removal line 23a, a water removal valve 23b, a buffer tank 23c, a water return line 23d, a water return valve 23e, a pump 23f, a water sampling line 23g, a water sampling valve 23h, and a cultivation water draining section 23i.

[0043] The water removal line 23a is a piping section that connects the ultraviolet sterilization tank 20 and the buffer tank 23c, and is provided with a water removal valve 23b (on / off valve). The buffer tank 23c stores the cultivation water transferred from the ultraviolet sterilization tank 20 via the water removal line 23a. The water return line 23d is a piping section that connects the buffer tank 23c and the third transfer line 43 downstream of the on / off valve 43a, and is provided with a water return valve 23e (on / off valve) and a pump 23f.

[0044] The water sampling line 23g is a piping section that connects the water removal valve 23b of the water removal line 23a and the buffer tank 23c to the cultivation water draining section 23i, and the piping section is provided with a water sampling valve 23h (opening and closing valve). The cultivation water draining section 23i is provided so that a user can extract a part of the cultivation water outside the device to check the condition of the cultivation water. The water removal valve 23b, the water return valve 23e, and the water collection valve 23h described above are motorized valves, solenoid valves, or the like, and are adapted to operate under the control of the control device 60 together with the pump 23f.

[0045] The lower water level gauge 24 detects whether the water level of the cultivation water in the ultraviolet sterilization tank 20 is lower than the net member 21. This lower water level gauge 24 is disposed in the lower space of the ultraviolet sterilization tank 20, above the connection position of the water removal line 23a. The upper water level gauge 25 detects whether the water level of the cultivation water in the ultraviolet sterilization tank 20 is higher than the mesh member 21. The upper water level gauge 25 is disposed in the upper space of the ultraviolet sterilization tank 20, above the connection position of the fourth transfer line 44. The lower water level gauge 24 and the upper water level gauge 25 described above are connected to the control device 60.

[0046] The cultivation water transfer device 23 configured as described above operates under the control of the control device 60. For example, when receiving algae and cultivation water from the third transfer line 43 into the ultraviolet sterilization tank 20 and separating the cultivation water from the algae using the mesh member 21, the cultivation water transfer device 23 opens the water removal valve 23b of the water removal line 23a and lowers the water level of the cultivation water in the ultraviolet sterilization tank 20 below the mesh member 21.

[0047] Furthermore, after ultraviolet irradiation, the cultivation water transfer device 23 opens the water return valve 23e of the water return line 23d and operates the pump 23f to return the cultivation water stored in the buffer tank 23c to the ultraviolet sterilization tank 20, raising the water level in the ultraviolet sterilization tank 20 above the mesh member 21. This makes it possible to transfer (return) the algae from the ultraviolet sterilization tank 20 to the first cultivation tank 11 via the fourth transfer line 44.

[0048] Returning to FIG. 1, each of the multiple cultivation tanks 10 is provided with a photographing device 50. The photographing device 50 is fixed at a fixed point in each cultivation tank 10 and photographs the algae. Each of the multiple cultivation tanks 10 is also provided with a measuring device 51 that measures the state quantity of the cultivation water. The measuring device 51 includes at least one of a pH detector, a carbon dioxide dissolution detector, and a liquid analyzer. The measuring device 51 may also include a water thermometer, a flow meter, a luminometer, or other sensors. The above-mentioned imaging devices 50 and measuring devices 51 are connected to a control device 60.

[0049] The control device 60 comprises a data processing unit 61 that processes various data input from the photographing device 50, the measuring device 51, the lower water level gauge 24, the upper water level gauge 25, etc., and a device control unit 62 that controls the operation of various devices provided in the cultivation tank 10 and the ultraviolet sterilization tank 20, and the algae transfer device 40. The control device 60 comprises a calculation unit such as a CPU (not shown), storage units such as a RAM, a ROM, a hard disk drive (HDD), a solid state drive (SSD), etc., and an input / output interface for exchanging data with each of the constituent devices, all connected by a bus (not shown). In addition to each of the constituent devices described above, a display device such as a display, and input devices such as a mouse and a keyboard (not shown) are connected to the input / output interface.

[0050] The memory unit stores a program that the calculation unit reads out and executes, and the control device 60 determines the degree of algae growth, determines whether the algae are diseased, transports the algae based on these determinations, and sterilizes the algae in accordance with the program, as described below. Specifically, the control device 60 determines the degree of algae growth and whether the algae are diseased based on the results of photography by the photography device 50, and also sterilizes the algae at predetermined time intervals.

[0051] Figure 3 is a flow chart explaining the process of transferring algae from the first cultivation tank 11 to the second cultivation tank 12 in the algae cultivation apparatus 1 according to the first embodiment. Note that while Figure 3 shows the flow of transferring algae from the first cultivation tank 11 to the second cultivation tank 12, the flow of transferring algae from the second cultivation tank 12 to the third cultivation tank 13 is similar. 3, first, the control device 60 starts counting the time ts (step S1). The time ts is the residence time of the algae in the first cultivation tank 11.

[0052] Next, the control device 60 judges whether the time ts has reached a predetermined time (Check time) (step S2). The predetermined time is a periodic time for the control device 60 to judge the degree of algae growth and the presence or absence of algae disease. The periodic time may be set to a fixed time such as one hour, but may be changed appropriately according to the growth rate of the algae.

[0053] When the time ts reaches the predetermined time (step S2: YES), the control device 60 operates the photographing device 50 to obtain image data of the algae and processes the image data (step S3). The control device 60 obtains, for example, 10 pieces of image data captured 10 times by the photographing device 50 at one-frame intervals.

[0054] Next, the control device 60 judges whether the algae have a disease based on the image data (step S4). Specifically, the control device 60 judges whether the algae have a disease by calculating the range of color (white, red, etc.) caused by the algae disease. For example, the control device 60 digitizes the area for each color in the image data and calculates the distribution. Then, a threshold value is set to determine whether each disease has occurred, and the control device 60 judges that the algae have a disease when the area of ​​a specific color determined to be a disease exceeds the threshold value.

[0055] If it is determined that the algae have become diseased (if step S4 is "Yes"), the control device 60 suspends the cultivation of the algae. If the coloring range of the predetermined color of the algae exceeds a predetermined threshold, the control device 60 operates the algae transfer device 40 to transfer the algae from the first cultivation tank 11 (in this embodiment, via the ultraviolet sterilization tank 20) ​​to the disposal tank 30. The diseased algae are then disposed of in the disposal tank 30.

[0056] If it is determined that the algae are not diseased (step S4 is "No"), the control device 60 determines whether the size of the algae at time ts (Size(ts)) is larger than a predetermined size (Check size) based on the image data (step S5). The predetermined size is the maximum size of the algae determined for each cultivation tank 10.

[0057] The control device 60, for example, binarizes the image data acquired by the image capture device 50, and calculates the surface area of ​​the portion having the color of the algae. Then, a threshold is set based on the correlation between the surface area and weight of the algae acquired in advance, and the control device 60 calculates the surface area of ​​the portion having the color of the algae in each image data, and when the average value exceeds the threshold, it determines that the algae has exceeded the maximum size determined for each cultivation tank 10.

[0058] If it is determined that the algae have not exceeded the maximum size determined for each cultivation tank 10 (if step S5 is "NO"), the process returns to step S1, and the control device 60 restarts counting the time ts. On the other hand, if it is determined that the algae have exceeded the maximum size determined for each cultivation tank 10 (if step S5 is "YES"), the control device 60 opens the opening / closing valve 41a of the first transfer line 41 (step S6). With the above, the transfer of the algae from the first cultivation tank 11 to the second cultivation tank 12 is completed.

[0059] Figure 4 is a flow chart explaining the process of transferring algae from the first cultivation tank 11 to the ultraviolet sterilization tank 20 in the algae cultivation apparatus 1 according to the first embodiment. Note that while Figure 4 shows the flow of transferring algae from the first cultivation tank 11 to the ultraviolet sterilization tank 20, the flow of transferring algae from the second cultivation tank 12 to the ultraviolet sterilization tank 20 and the flow of transferring algae from the third cultivation tank 13 to the ultraviolet sterilization tank 20 are similar. 4, first, the control device 60 starts counting the time tuv (step S11). The time tuv is the residence time of the algae in the first cultivation tank 11.

[0060] Next, the control device 60 judges whether the time ts reaches a predetermined time (Uv time) (step S12). The predetermined time is a cycle time for sterilizing the algae. The cycle time may be set to a fixed time such as 12 hours and 25 minutes in accordance with the natural low tide cycle, but may be changed appropriately in accordance with the growth rate of the algae.

[0061] When the time tuv reaches the predetermined time (when step S12 is "YES"), the controller 60 opens the on-off valve 43a of the third transfer line 43 (step S13) and operates the pump 43b of the third transfer line 43 (step S14). With the above, the transfer of the algae from the first cultivation tank 11 to the ultraviolet sterilization tank 20 is completed.

[0062] Figures 5 and 6 are flow charts illustrating the algae sterilization process in the algae cultivation apparatus 1 according to the first embodiment. Note that the circled reference symbol 1 in Figures 4 and 5 indicates the connection between the two flows. Once the transfer of the algae from the first cultivation tank 11 to the ultraviolet sterilization tank 20 is completed, the control device 60 closes the opening / closing valve 43a of the third transport line 43 (step S21) and stops the pump 43b of the third transport line 43 (step S22), as shown in FIG. 5.

[0063] Next, the control device 60 opens the water removal valve 23b of the water removal line 23a connected to the ultraviolet sterilization tank 20 (step S23) and operates the pump 23f (step S24). If the user needs to collect the culture water to check the state of the culture water (if "YES" is returned in step S25), the control device 60 opens the water collection valve 23h of the water collection line 23g (step S26). After opening the water collection valve 23h of the water collection line 23g and extracting a portion of the culture water at the culture water extraction unit 23i, the control device 60 closes the water collection valve 23h of the water collection line 23g (step S27).

[0064] Next, the control device 60 checks whether the water level of the growth water in the ultraviolet sterilization tank 20 is lower than the mesh member 21 using the lower water level gauge 24 (step S28). If the water level of the growth water in the ultraviolet sterilization tank 20 is lower than the mesh member 21 (step S28 is "YES"), the control device 60 stops the pump 23f (step S29) and closes the water removal valve 23b of the water removal line 23a (step S30).

[0065] Next, the control device 60 operates the moving device 26 to adjust the height of the net member 21 supporting the algae (step S31). Then, the control device 60 causes the ultraviolet light source 22 to irradiate ultraviolet light toward the algae (step S32). Next, the control device 60 checks whether the ultraviolet light irradiation time has reached a preset irradiation time (step S33). If the ultraviolet light irradiation time has reached the preset irradiation time (if "YES" in step S33), the control device 60 stops the ultraviolet light irradiation from the ultraviolet light source 22 (step S34).

[0066] After stopping the ultraviolet irradiation from the ultraviolet light source 22, the control device 60 returns the height of the net member 21 supporting the algae to the initial position as shown in Fig. 6 (step S41). Next, the control device 60 opens the water return valve 23e of the water return line 23d (step S42) and operates the pump 23f (step S43). Then, the control device 60 checks with the upper water level gauge 25 whether the water level of the cultivation water in the ultraviolet sterilization tank 20 is higher than the net member 21 (step S44).

[0067] When the water level in the ultraviolet sterilization tank 20 rises above the net member 21 (step S44: YES), the control device 60 stops the pump 23f (step S45) and closes the water return valve 23e of the water return line 23d (step S46). Then, the control device 60 opens the opening / closing valve 44a of the fourth transfer line 44 (step S47). In this manner, the return of the algae from the ultraviolet sterilization tank 20 to the first cultivation tank 11 is completed.

[0068] As described above, the algae cultivation apparatus 1 according to this embodiment comprises a cultivation tank 10 for cultivating algae, an algae transfer device 40 for transferring the algae from the cultivation tank 10, a photography device 50 for photographing the algae in the cultivation tank 10, and a control device 60 for operating the algae transfer device 40 based on the photographing results of the photography device 50. With this configuration, algae can be automatically transferred from the cultivation tank 10 in accordance with the degree of algae cultivation.

[0069] Furthermore, in the algae cultivation apparatus 1 according to this embodiment, the control device 60 determines the degree of algae cultivation based on the size of the algae photographed by the photography device 50. With this configuration, the degree of algae cultivation can be easily determined from the size of the algae photographed by the photography device 50, eliminating the need for a conventional process of measuring the wet weight of the algae, and also making it possible to set a cultivation environment suitable for algae cultivation by determining the degree of algae cultivation, thereby enabling algae to be cultivated quickly.

[0070] Furthermore, the algae cultivation apparatus 1 according to this embodiment is equipped with a second cultivation tank 12 (second cultivation tank) having a larger volume than the first cultivation tank 11, and when the cultivation level of the algae exceeds a predetermined threshold (Check size), the control device 60 operates the algae transfer device 40 to transfer the algae from the first cultivation tank 11 to the second cultivation tank 12. With this configuration, by transferring the algae to the cultivation tank 10 with a larger volume in accordance with the cultivation level of the algae so as to keep the density of the algae in each cultivation tank 10 constant, it is possible to stabilize the arrival of light necessary for the photosynthesis of the algae and to cultivate the algae with high efficiency.

[0071] Furthermore, in the algae cultivation apparatus 1 according to this embodiment, the control device 60 determines whether or not the algae are diseased based on the color of the algae photographed by the photographing device 50. With this configuration, it is also possible to detect diseases caused by pathogenic microorganisms, such as "white rot" and "red rot", which are diseases of seaweed.

[0072] Furthermore, the algae cultivation apparatus 1 according to this embodiment is equipped with a waste tank 30 for disposing of algae, and when the color development range of a predetermined color of the algae exceeds a predetermined threshold, the control device 60 operates the algae transfer device 40 to transfer the algae from the cultivation tank 10 to the waste tank 30. With this configuration, diseased algae can be promptly disposed of, thereby reducing loss costs due to the outbreak of disease.

[0073] Furthermore, in the algae cultivation apparatus 1 according to this embodiment, the cultivation tank 10 contains cultivation water in which the algae are cultivated, and is equipped with a measuring device 51 (pH detector, carbon dioxide dissolution detector, liquid analyzer, etc.) that measures the state quantities of the cultivation water. With this configuration, a recipe is created for the optimum cultivation environment (pH, carbon dioxide solubility, amount of nutrients, etc.) for each type of algae, and the cultivation environment is managed and controlled according to the degree of algae cultivation, allowing algae to be cultivated with high efficiency. Furthermore, the creation of the recipe makes it possible to ensure a stable supply of algae, and by correlating this with nutritional value and palatability, it is possible to increase the commercial value and contribute to the branding of algae production.

[0074] The algae cultivation apparatus 1 according to this embodiment includes a cultivation tank 10 in which algae are cultivated in cultivation water, and an ultraviolet sterilization device 2 that irradiates the algae with ultraviolet light after drying them out of the cultivation water. With this configuration, diatoms that adhere to the algae, consume carbon dioxide added to the cultivation water, repeat photosynthesis, and grow faster than the algae to be cultivated, blocking the light absorption of the algae to be cultivated, can be removed by irradiating them with ultraviolet light. Note that a backup image capture device 50 for capturing images of the algae may also be provided in the ultraviolet sterilization tank 20 of the ultraviolet sterilization device 2.

[0075] Furthermore, in the algae cultivation apparatus 1 according to this embodiment, the ultraviolet sterilization device 2 comprises an ultraviolet sterilization tank 20 that receives the algae and cultivation water from the cultivation tank 10, a mesh member 21 that is provided inside the ultraviolet sterilization tank 20 and separates the cultivation water from the algae, and an ultraviolet light source 22 that irradiates ultraviolet rays onto the algae supported by the mesh member 21. With this configuration, it is possible to simulate the natural process of the ebb and flow of seawater and the drying out process caused by the ultraviolet rays of sunlight, and diatoms attached to the algae can be efficiently removed.

[0076] Furthermore, in the algae cultivation apparatus 1 according to this embodiment, the ultraviolet sterilization device 2 is equipped with a cultivation water transfer device 23 that lowers the water level of the cultivation water in the ultraviolet sterilization tank 20 below the mesh member 21. With this configuration, the cultivation water can be transferred (dewatered) from the ultraviolet sterilization tank 20, so the water level can be lowered without installing a large-volume ultraviolet sterilization tank 20, and the mesh member 21 can dry out the algae from the cultivation water.

[0077] Furthermore, in the algae cultivation device 1 according to this embodiment, the cultivation water transfer device 23 returns the cultivation water after ultraviolet irradiation, and raises the water level in the ultraviolet sterilization tank 20 above the mesh member 21. With this configuration, by returning the cultivation water to the ultraviolet sterilization tank 20, the algae supported on the mesh member 21 can be floated by the cultivation liquid, making it possible to transfer the algae.

[0078] Furthermore, in the algae cultivation device 1 according to this embodiment, the ultraviolet sterilization tank 20 is equipped with a lower water level gauge 24 that detects whether the water level of the cultivation water is lower than the mesh member 21. With this configuration, the water level of the cultivation water in the ultraviolet sterilization tank 20 can be reliably lowered below the mesh member 21.

[0079] Furthermore, in the algae cultivation device 1 according to this embodiment, the ultraviolet sterilization tank 20 is equipped with an upper water level gauge 25 that detects whether the water level of the cultivation water is higher than the mesh member 21. With this configuration, the water level of the cultivation water in the ultraviolet sterilization tank 20 can be reliably raised above the mesh member 21.

[0080] Furthermore, in the algae cultivation apparatus 1 according to this embodiment, the ultraviolet sterilization device 2 includes a moving device 26 that moves the net member 21 closer to or farther from the ultraviolet light source 22. With this configuration, by moving the net member 21 closer to or farther from the ultraviolet light source 22, it is possible to adjust the amount of ultraviolet light that hits the algae.

[0081] Furthermore, in the algae cultivation apparatus 1 according to this embodiment, the ultraviolet sterilization device 2 includes an ultraviolet light emitting diode that irradiates ultraviolet light. With this configuration, ultraviolet light can be irradiated onto the algae with reduced power consumption.

[0082] Second Embodiment Next, a second embodiment of the present invention will be described. In the following description, the same or equivalent configurations as those in the above-described embodiment are given the same reference numerals, and the description thereof will be simplified or omitted.

[0083] FIG. 7 is a configuration diagram of an algae cultivation apparatus 1 according to the second embodiment. The algae cultivation apparatus 1 of the second embodiment is not provided with the batch-type ultraviolet sterilization device 2 described in the first embodiment, but with a continuous ultraviolet sterilization device 2 that irradiates ultraviolet rays during the process of transferring the algae from the first cultivation tank 11 to the second cultivation tank 12. Although not shown, a similar continuous ultraviolet sterilization device 2 is also provided during the process of transferring the algae from the second cultivation tank 12 to the third cultivation tank 13, and ultraviolet rays are irradiated to the algae.

[0084] 7 is provided in the middle of a first transfer line 41A that transfers algae from the first cultivation tank 11 to the second cultivation tank 12. An opening / closing valve 41b is provided on the first transfer line 41A upstream of the ultraviolet sterilization device 2. In addition, an opening / closing valve 41c is provided on the first transfer line 41A downstream of the ultraviolet sterilization device 2.

[0085] The ultraviolet sterilization device 2 includes a drying device 70 that dries out the algae from the cultivation water and transports it, and an ultraviolet light source 22 that irradiates ultraviolet rays onto the algae being transported by the drying device 70. The drying device 70 includes a drying preparation tank 71, a conveyor device 72, a transport control device 73, a water receiving tank 74, and a drying completion tank 75. The above-mentioned imaging device 50 that photographs the algae may be provided as a backup on the conveyor device 72.

[0086] The drying preparation tank 71 is connected to the first transfer line 41A on the upstream side, and places the algae received from the first transfer line 41A in a predetermined width on a conveyor device 72. The conveyor device 72 transports the algae placed thereon from the drying preparation tank 71. The conveyor device 72 has a transport surface provided with slits, holes, etc. (not shown), so that the cultivation water and the cultivation water adhering to the algae can be dropped off from the transport surface, allowing the algae to be dried out.

[0087] The transport control device 73 operates the conveyor device 72 under the control of the control device 60. The water receiving tank 74 is disposed below the conveyor device 72 and receives the cultivation water that falls from the transport surface of the conveyor device 72. The drying completion tank 75 is disposed downstream of the conveyor device 72 and receives the algae from the conveyor device 72 and the cultivation water from the water receiving tank 74. The drying completion tank 75 is connected to the first transport line 41A on the downstream side and transfers the algae and cultivation water that have been subjected to ultraviolet sterilization treatment to the next cultivation tank 10.

[0088] The ultraviolet light source 22 is installed on the transport path of the conveyor device 72. A blower device 76 is installed on the transport path upstream of the ultraviolet light source 22. The blower device 76 operates under the control of the control device 60, and promotes the drainage of the cultivation water from the transport surface of the conveyor device 72 by blowing air to the algae upstream of the ultraviolet light source 22.

[0089] FIG. 8 is a flow chart illustrating the algae sterilization process in the algae cultivation apparatus 1 according to the second embodiment. At the timing of transferring the algae from the first cultivation tank 11 to the second cultivation tank 12 described in the first embodiment, the control device 60 opens the opening / closing valve 41b of the first transport line 41A, and receives the algae from the first cultivation tank 11 into the drying preparation tank 71 (step S61).

[0090] Next, the control device 60 operates the air blower 76 (step S62) and the ultraviolet light source 22 (step S63). Then, the control device 60 starts the transport control device 73 and operates the conveyor device 72 (step S64). The algae is dried out of the cultivation water by being placed on the conveyor device 72 from the drying preparation tank 71, and after being exposed to air and ultraviolet light during transport by the conveyor device 72, it is placed into the drying completion tank 75.

[0091] Next, the control device 60 checks whether all the algae have entered the drying completion tank 75 (step S65). Whether all the algae have entered the drying completion tank 75 may be checked by time or by a photographing device (not shown). When all the algae have entered the drying completion tank 75 (step S65: YES), the control device 60 opens the opening / closing valve 41c of the first transfer line 41A downstream of the drying completion tank 75 (step S66). As a result, the algae are transferred from the drying completion tank 75 to the second cultivation tank 12.

[0092] According to the second embodiment described above, the ultraviolet sterilization device 2 is equipped with a drying device 70 that dries out the algae from the cultivation water and transports them, and an ultraviolet light source 22 that irradiates ultraviolet rays onto the algae being transported by the drying device 70, so that ultraviolet sterilization treatment can be performed efficiently in the process of transferring the algae from the first cultivation tank 11 to the second cultivation tank 12.

[0093] The ultraviolet sterilization device 2 of the second embodiment also includes a blower device 76 that blows air to the algae upstream of the ultraviolet light source 22 in the transport path of the drying device 70. With this configuration, blowing air to the algae promotes drying of the algae, thereby improving the efficiency of the ultraviolet sterilization process.

[0094] The drying device 70 also includes a conveyor device 72 that carries and transports the algae, and a water receiving tank 74 that is disposed below the conveyor device 72. With this configuration, the cultivation water is allowed to drip from the transport surface of the conveyor device 72, and the dripped cultivation water can be received in the water receiving tank 74 for reuse.

[0095] The ultraviolet sterilization device 2 of the second embodiment described above may be installed together with the ultraviolet sterilization device 2 of the first embodiment shown in Figures 1 and 2 so that ultraviolet sterilization processing can be selected by either device. Also, the ultraviolet sterilization device 2 of the second embodiment may be installed midway along the first conveyor line 41 and the second conveyor line 42 shown in Figure 1.

[0096] Third Embodiment Next, a third embodiment of the present invention will be described. In the following description, the same or equivalent configurations as those in the above-described embodiment are given the same reference numerals, and the description thereof will be simplified or omitted.

[0097] Figure 9 is a configuration diagram of an algae cultivation apparatus 1 according to a third embodiment. Figure 10 is an external view of an algae cultivation apparatus 1 according to a third embodiment. In Figure 9, reference numeral 3 denotes cultivation water, and reference numeral 4 denotes algae (the same applies to Figures 11 and onwards, which will be described later). In the algae cultivation apparatus 1 of the third embodiment, the volumes of the first cultivation tank 11, the second cultivation tank 12, and the third cultivation tank 13 are gradually increased in accordance with the degree of algae cultivation by increasing the number of cultivation tanks 10 installed. Specifically, the first cultivation tank 11 has one cultivation tank 10, the second cultivation tank 12 has two cultivation tanks 10, and the third cultivation tank 13 has four cultivation tanks 10.

[0098] A drying device 70 (continuous ultraviolet sterilization device 2) that dehydrates and dries the algae described in the second embodiment is provided downstream of each cultivation tank 10. In the third embodiment, a seed algae selection tank 80 is connected to the third cultivation tank 13. The seed algae selection tank 80 is a tank for selecting the next algae species to be cultivated from the algae in the final stage of cultivation in the third cultivation tank 13. The seed algae selection tank 80 is connected to the first cultivation tank 11 via a seed algae supply line 81.

[0099] A drying processing device 90 that dries algae in the final stage of cultivation is provided further downstream of the drying device 70 that dehydrates and dries algae downstream of the third cultivation tank 13. In addition, the water treatment section (the above-mentioned water receiving tank 74) of the drying device 70 that dehydrates and dries algae downstream of the third cultivation tank 13 joins with the water treatment section downstream and is connected to a large water treatment tank 100.

[0100] The water treatment tank 100 purifies the cultivation water used for cultivating algae to maintain the water quality, and generates cultivation water by dissolving nutrients and carbon dioxide. This reduces the amount of seawater or artificial seawater required for cultivation water, which in turn reduces transportation costs and increases the flexibility of the location of the algae cultivation device 1. It also reduces the burden on the ocean, rivers, etc. caused by discharging the cultivation water.

[0101] The water treatment tank 100 is connected to each of the cultivation tanks 10, namely, the first cultivation tank 11, the second cultivation tank 12, and the third cultivation tank 13, via a cultivation water supply line 101. The cultivation water supply line 101 is provided with a pump 101A that lifts the cultivation water. Next, configurations of the cultivation tank 10, the drying device 70, and the drying processing device 90 of the third embodiment will be described with reference to Figs.

[0102] FIG. 11 is an external view of the cultivation tank 10 according to the third embodiment. As shown in FIG. 11, the cultivation tank 10 includes a cultivation container 14 and a light irradiation device 15. The cultivation container 14 has a rectangular box shape in plan view with an open top. The above-mentioned cultivation water supply line 101 is disposed above the cultivation container 14, and cultivation water is supplied from a plurality of nozzles 101a provided on the cultivation water supply line 101. The nozzle 101a is provided with a flow rate control valve 101b, which allows the input amount (flow rate) of the cultivation water to be adjusted. The flow of the cultivation water can be changed by changing the shape of the water channel in the cultivation container 14, so the water channel may be formed so as to form a turbulent flow or laminar flow where necessary.

[0103] The light irradiation device 15 is disposed further above the growth water supply line 101, and irradiates the inside of the growth container 14 with light necessary for the photosynthesis of the algae. A plurality of fixing plates 14a that form flow paths for the algae and the growth water are provided inside the growth container 14. The fixing plates 14a are arranged alternately to form a meandering flow path inside the growth container 14. By making the flow path meandering in this manner, the residence time of the algae in the growth container 14 can be increased.

[0104] Furthermore, inside the cultivation container 14, multiple movable plates 14b capable of blocking the flow path are provided. The movable plates 14b are slidably attached to the rear sides of some of the fixed plates 14a. In this embodiment, three movable plates 14b are provided so that the flow path can be blocked at three locations. Vent holes 14c for removing algae from the sides are provided in three areas upstream of the three movable plates 14b inside the cultivation container 14. The vent holes 14c are provided so as to be openable and closable by an opening and closing device (not shown), and are connected to a waste tank (not shown).

[0105] 9, it is preferable to provide a photography device 50 for photographing the algae in each of the three areas upstream of the three movable plates 14b of the growth container 14. The photography device 50 may be installed above the growth container 14, or may be fixed to the fixed plate 14a or the like and installed inside the growth container 14. Alternatively, a transparent window may be provided in at least a part of the growth container 14, and the inside of the growth container 14 may be photographed through the window.

[0106] FIG. 12 is an external view of a drying device 70 according to the third embodiment. As shown in Fig. 12, the drying device 70 includes a drying preparation tank 71, a conveyor device 72, a water receiving tank 74, and a drying completion tank 75. The drying preparation tank 71 has an inlet 71a for receiving algae and cultivation water, and an outlet 71b for discharging the algae and cultivation water. The drying preparation tank 71 may include a mixer that crushes the algae received from the inlet 71a, uniforms the size, and discharges the crushed algae from the outlet 71b.

[0107] The conveyor device 72 is equipped with a mesh belt 72a that separates the cultivation water from the algae discharged from the discharge port 71b of the drying preparation tank 71, and a plurality of delivery rollers 72b that transport the mesh belt 72a. At least one of the plurality of delivery rollers 72b may be a vacuum roller that sucks up the cultivation water. At the downstream end of the conveyor device 72, a pressure roller 77 is provided that uniformly presses the dried algae.

[0108] The drying out apparatus 70 of the third embodiment is provided with a photographing device 50 that photographs the algae being transported by the conveyor device 72. The other configurations are similar to those of the drying out apparatus 70 of the second embodiment described above.

[0109] FIG. 13 is an external view of a drying processing apparatus 90 according to the third embodiment. 13, the drying processing device 90 includes a conveyor device 91, a dryer 92, and a roll cutter 93. The conveyor device 91 includes a plurality of delivery rollers 91a and a mesh belt 91b that is delivered by the plurality of delivery rollers 91a.

[0110] The dryer 92 blows hot air onto the algae placed on the mesh belt 91b to dry the algae. The roll cutter 93 cuts the algae dried by the dryer 92 into sheets. The sheets of algae cut into sheets are stacked and transferred to the next processing step.

[0111] FIG. 14 is a flow chart showing the process of transferring algae from the cultivation tank 10 of the algae cultivation apparatus 1 according to the third embodiment. As shown in FIG. 14, first, the control device 60 adjusts the amount of culture water input to the culture tank 10 and determines the flow rate in the culture tank 10 (step S71).

[0112] Next, the control device 60 operates the photographing device 50 to obtain image data of the algae (step S72). The number of times n photographed by the photographing device 50 in step S72 may be externally settable. A threshold value V1 for determining the degree of growth of the algae may also be externally settable. The threshold value V1 is a threshold value that serves as a criterion for determining the degree of growth in an area (first area) upstream of the first movable plate 14b inside the cultivation container 14, and is a value based on a value Vmes that is calculated as the volume of the algae from the image data.

[0113] Next, the control device 60 judges whether the algae in the first area are diseased based on the image data acquired by the photographing device 50 of the first area (step S73). If it is judged that the algae are diseased (step S73 is "yes"), the control device 60 closes the flow path with the first movable plate 14b to isolate the first area of ​​the cultivation container 14 (step S74). Next, the control device 60 opens the vent hole 14c of the first area and transfers the algae from the vent hole 14c to a waste tank (not shown). The diseased algae are then disposed of in the waste tank.

[0114] If it is determined that the algae in the first area is not diseased (if step S73 is "no"), the control device 60 determines whether the growth level Vtn1 of the algae in the first area is greater than the threshold value V1 based on the image data acquired by the photographing device 50 in the first area (step S75).

[0115] If it is determined that the growth level Vtn1 of the algae in the first area does not exceed the threshold value V1 (if step S75 is "YES"), the control device 60 closes the flow path with the first movable plate 14b to isolate the first area of ​​the growth container 14 (step S76). Next, the control device 60 sets a residence time Ts1 for the algae in the first area (step S76) and causes the algae to reside (grow) in the first area for the residence time Ts1 (step S78). After the residence time Ts1 has elapsed, the process returns to step S73, and the control device 60 again determines whether the algae in the first area is diseased and the growth level.

[0116] When it is determined that the growth level Vtn1 of the algae in the first area exceeds the threshold value V1 (step S75 is "NO"), the control device 60 opens the first movable plate 14b if it is closed (step S79). This completes the transfer of the algae from the first area to the second area of ​​the cultivation container 14. Note that the second area is the area inside the cultivation container 14 that is downstream of the first movable plate 14b and upstream of the second movable plate 14b.

[0117] The control device 60 repeats the above steps S72 to S79 ​​in the second area (step S80). This completes the transfer of the algae from the second area to the third area of ​​the cultivation container 14. The third area is the area downstream of the second movable plate 14b and upstream of the third movable plate 14b inside the cultivation container 14. The control device 60 repeats the above steps S72 to S79 ​​in the third area (step S81). In this manner, the algae are transferred from the cultivation tank 10 to the drying device 70 (ultraviolet sterilization device 2).

[0118] FIG. 15 is a flow chart showing the transfer of algae in the drying device 70 of the algae cultivation apparatus 1 according to the third embodiment. 15, first, the control device 60 operates the blower device 76 (step S91), and operates the ultraviolet light source 22 (step S92). Then, the control device 60 starts up the transfer control device 73, and operates the conveyor device 72 (step S93).

[0119] Next, the control device 60 operates the photographing device 50 installed on the conveyor device 72 to obtain image data of the algae, and performs image processing on the image data (step S94). The control device 60 obtains, for example, 10 pieces of image data photographed 10 times by the photographing device 50 at one-frame intervals.

[0120] Next, the control device 60 judges whether the algae are diseased or not based on the image data (step S95). If the algae are found to be diseased during this transportation stage (step S95 is "yes"), the control device 60 stops the conveyor device 72 to interrupt the transportation and cultivation of the algae.

[0121] If it is determined that the algae are not diseased during the transportation stage (step S95 is "NO"), the control device 60 checks whether or not all the algae have entered the drying completion tank 75 based on the weight on the conveyor device 72 (step S96). The weight of the algae can be measured, for example, by a load cell (not shown) provided on the delivery roller 72b of the conveyor device 72.

[0122] When all the algae have entered the drying completion tank 75 (if step S96 is "YES"), the control device 60 causes the transport control device 73 to stop the conveyor device 72 (step S97). Next, the control device 60 stops the ultraviolet light source 22 (step S98) and also stops the air blower 76 (step S99). In this way, by repeating the above-mentioned flow shown in Figs. 14 and 15, the cultivation tank 10 can be changed according to the degree of cultivation of the algae, and the algae can be cultivated efficiently.

[0123] Although the preferred embodiment of the present invention has been described above with reference to the drawings, the present invention is not limited to the above embodiment. The shapes and combinations of the components shown in the above embodiment are merely examples, and various modifications can be made based on design requirements, etc., without departing from the spirit of the present invention. [Explanation of symbols]

[0124] 1 Algae growth device 2 Ultraviolet sterilizer 10 Growth tank 11 1st growth tank 12 Second cultivation tank (Second cultivation tank) 13 Third incubation tank (second incubation tank) 20 Ultraviolet sterilization tank 21 Net components 22 UV light source 23 Cultivation water transfer device 24 Lower water level gauge 25 Upper water level gauge 26 Mobile Devices 30 Waste tank 40 Algae transfer device 50 Imaging Equipment 51 Measuring Equipment 60 Control device 70 Drying device 72 Conveyor equipment 74 Water tank 76 Blower

Claims

1. a cultivation tank in which algae are cultivated in cultivation water; An algae cultivation apparatus comprising: an ultraviolet sterilization device that dries out the algae from the cultivation water and irradiates them with ultraviolet rays.

2. The ultraviolet sterilization device is an ultraviolet sterilization tank for receiving the algae and the cultivation water from the cultivation tank; A mesh member provided inside the ultraviolet sterilization tank for separating the cultivation water from the algae; 2. An algae cultivation apparatus as claimed in claim 1, further comprising an ultraviolet light source which irradiates ultraviolet light onto the algae supported by the net member.

3. The algae cultivation apparatus according to claim 2, characterized in that the ultraviolet sterilization device is provided with a cultivation water transfer device that lowers the water level of the cultivation water in the ultraviolet sterilization tank below the mesh member.

4. The algae cultivation apparatus according to claim 3, characterized in that the cultivation water transfer device returns the cultivation water after the ultraviolet radiation is irradiated, and raises the water level of the cultivation water in the ultraviolet sterilization tank above the mesh member.

5. An algae cultivation device as described in any one of claims 2 to 4, characterized in that the ultraviolet sterilization tank is equipped with a lower water level gauge that detects when the water level of the cultivation water is lower than the mesh member.

6. An algae cultivation device as described in any one of claims 2 to 5, characterized in that the ultraviolet sterilization tank is equipped with an upper water level gauge that detects when the water level of the cultivation water is higher than the mesh member.

7. An algae cultivation apparatus as described in any one of claims 2 to 6, characterized in that the ultraviolet sterilization device is provided with a moving device for moving the net member closer to and away from the ultraviolet light source.

8. The growth tank is provided in plurality, An algae cultivation apparatus as described in any one of claims 2 to 7, characterized in that one ultraviolet sterilization device is provided for each of a plurality of cultivation tanks.

9. The ultraviolet sterilization device is A drying device that dries and transports the algae from the cultivation water; 2. The algae cultivation apparatus according to claim 1, further comprising an ultraviolet light source that irradiates ultraviolet light onto the algae being transported by the drying device.

10. The algae cultivation apparatus according to claim 9, characterized in that the ultraviolet sterilization device is provided with a blower device that blows air onto the algae upstream of the ultraviolet light source in the transport path of the drying device.

11. The drying device is A conveyor device that carries and transports the algae; 11. An algae cultivation apparatus as claimed in claim 9 or 10, further comprising a water receiving tank arranged below the conveyor apparatus.

12. An algae cultivation apparatus according to any one of claims 9 to 11, characterized in that one ultraviolet sterilization device is provided for each cultivation tank.

13. An algae cultivation apparatus according to any one of claims 1 to 12, characterized in that the ultraviolet sterilization device is equipped with an ultraviolet light emitting diode that irradiates ultraviolet light.

Images