Centrifugal-type automatic microalgae harvesting device

Abstract

A disclosed centrifugal-type automatic microalgae harvesting device comprises: a centrifugal separation chamber for temporarily storing a culture medium in which microalgae supplied from a main incubator or sub-incubators are cultured; a harvesting motor for providing, into the centrifugal separation chamber, a centrifugal force that allows high-speed rotation required for harvesting the microalgae; and a harvesting drum which is provided inside the centrifugal separation chamber so as to receive, therein, the culture medium in which the microalgae are cultured, and which receives the centrifugal force from the harvesting motor so as to separate the microalgae from the culture medium such that the microalgae are collected and harvested.

Description

Centrifugal type automatic microalgae harvesting device

[0001] The present invention (Disclosure) relates to a centrifugal type automatic microalgae harvesting device that enables the harvesting of microalgae by separating the microalgae from the culture medium in which the microalgae are cultured using a centrifugal force rotating at a high speed.

[0002] This section provides background information related to the present disclosure, which is not necessarily prior art.

[0003] Microalgae are single-celled photosynthetic organisms that inhabit oceans or freshwater and are commonly referred to as phytoplankton. Because they are very common organisms widely distributed across the globe, they constitute the lowest layer of the food chain in marine ecosystems.

[0004] The reason these common microalgae have recently been receiving significant attention in relation to alternative energy development is due to the characteristics they possess.

[0005] The first characteristic of microalgae is that they can increase their population explosively by dividing very easily through cell division. While the production of corn or sugarcane, which are major raw materials for biofuels, cannot double in a short period, single-celled microalgae can increase their population by several times in a single day by dividing rapidly, provided that the culture environment, such as water temperature and nutrients, is suitable.

[0006] The second characteristic is that, unlike conventional plants, microalgae do not require organelles such as stems or roots, allowing all cells to participate in photosynthesis. Since the fact that all cells perform photosynthesis implies greater efficiency in biomass production, the amount of biofuel obtained from microalgae when cultivated in the same area is significantly higher than that secured from plants such as corn or soybeans.

[0007] Finally, the third characteristic of microalgae is that they do not incur opportunity costs because they do not require cultivation on farmland. Unlike current biofuels made from grain resources, they are unlikely to become embroiled in controversy regarding the conversion of valuable food into fuel, and since they exist underwater, they do not need to occupy land where other crops could grow.

[0008] For this reason, research and development regarding systems or devices for cultivating microalgae is actively underway.

[0009] Meanwhile, microalgae die off as they enter the late-stage mortality phase; this acts as a major cause of culture medium contamination, hindering a stable culture environment. Therefore, harvesting during the optimal growth period is essential.

[0010] Various conventional methods for harvesting microalgae are known, including filtration, coagulation, flotation, and biological harvesting.

[0011] However, the above harvesting methods had problems of being inefficient in terms of time and labor.

[0012] The present invention (Disclosure) aims to provide a centrifugal type automatic microalgae harvesting device that enables the harvesting of microalgae by separating the microalgae from the culture medium in which the microalgae are cultured using a centrifugal force rotating at a high speed.

[0013] This section provides a general summary of the disclosure and is not a comprehensive disclosure of its full scope or all of its features.

[0014] To solve the above-mentioned problem, a centrifugal type automatic microalgae harvesting device according to any aspect of the present invention comprises: a centrifugal chamber that temporarily stores a culture medium in which microalgae are cultured, supplied from a main culture medium or a sub-culture medium; a harvesting motor that provides centrifugal force rotating at a high speed required for harvesting microalgae into the centrifugal chamber; and a harvesting drum installed inside the centrifugal chamber, which receives the culture medium in which microalgae are cultured, and receives centrifugal force from the harvesting motor to separate the microalgae from the culture medium and capture and harvest the microalgae.The centrifugal chamber is formed in the shape of a hollow enclosure with an open top and a closed bottom, with the closed bottom side mounted and supported by a frame, and the open top of the centrifugal chamber is selectively opened and closed by a cover to harvest microalgae separated from the culture medium, and a culture medium supply pipe supplying the culture medium in which microalgae are cultured and a culture medium circulation pipe for directly circulating the culture medium in which microalgae are separated are installed adjacent to the top and bottom sides of the centrifugal chamber, respectively, and an upper water level sensor and a lower water level sensor are installed on the top and bottom sides of the centrifugal chamber, respectively, wherein the upper water level sensor detects the maximum allowable level and cuts off the supply, and the lower water level sensor prevents the level from falling below the minimum allowable level to maintain the stable centrifugal force of the harvesting motor, and a turbidity sensor is installed on the flow path guiding the main culture medium, the sub culture medium in which microalgae are cultured, or the centrifugal type automatic microalgae harvesting device. The above turbidity sensors are installed to supply the culture medium to the centrifugation chamber when the turbidity of the culture medium reaches a preset maximum turbidity value, and to automatically preserve the inoculum for the next cultivation by blocking the supply of the microalgae culture medium when the turbidity of the above turbidity sensors reaches 10% of the preset maximum turbidity value, and to automatically perform a continuous harvesting and cultivation cycle by linking the circulation of the separated culture medium through the culture medium circulation pipe with the control of the upper / lower water level sensors.

[0015] In a centrifugal type automatic microalgae harvesting device according to one aspect of the present invention, the centrifugal chamber may be formed to be transparent or translucent.

[0016] In a centrifugal type automatic microalgae harvesting device according to one aspect of the present invention, the harvesting motor is installed in a frame and the harvesting motor includes a centrifugal shaft that receives rotational force from a drive shaft and generates centrifugal force, wherein the centrifugal shaft is installed to rotatably penetrate vertically into the closed lower center of the centrifugal separation chamber and the lower end of the centrifugal shaft penetrating the closed lower part of the centrifugal separation chamber may be connected to the drive shaft of the harvesting motor by a power transmission element.

[0017] In a centrifugal type automatic microalgae harvesting device according to one aspect of the present invention, the harvesting drum is formed in the shape of a hollow housing with an open top and a closed bottom, wherein the closed bottom of the harvesting drum is detachably connected to the upper end of a centrifugal shaft extending into the interior of the centrifugal chamber, and the wall of the harvesting drum may be formed in the shape of a filter mesh to capture microalgae.

[0018] According to the present invention, since the microalgae and the culture medium are separated and the microalgae are harvested using a centrifugal force rotating at a high speed, the time and labor required for microalgae harvesting are significantly reduced.

[0019] FIG. 1 is a schematic diagram showing the installation state of a centrifugal type automatic microalgae harvesting device according to the present invention, and

[0020] FIG. 2 is a drawing showing a centrifugal type automatic microalgae harvesting device according to the present invention.

[0021] FIG. 1 is a schematic diagram showing the installation state of a centrifugal type automatic microalgae harvesting device according to the present invention, and the centrifugal type automatic microalgae harvesting device (100) according to the present invention is installed in a microalgae cultivation facility.

[0022] A microalgae culture facility includes a main culture vessel (10), one or more sub-culture vessels (20), and a centrifugal type automatic microalgae harvesting device (100) according to the present invention.

[0023] The main culture vessel (10) provides an artificial environment for culturing microalgae, receives water necessary for culturing microalgae from the outside, forms a medium by adding nutrients to the water, and inoculates microalgae into the medium to cultivate microalgae.

[0024] Additionally, the main culture vessel (10) optionally supplies a batch inoculated with microalgae to the sub-culture vessels (20) and supplies the culture medium in which the microalgae are cultured to the centrifugal type automatic microalgae harvesting device (100) according to the present invention.

[0025] The sub-incubators (20) provide an artificial environment for culturing microalgae, similar to the main incubator (10), and receive a medium inoculated with microalgae from the main incubator (10) to allow the microalgae to be expanded and cultured.

[0026] Additionally, the sub-culturers (20) supply the culture medium in which microalgae are cultured to the centrifugal type microalgae automatic harvesting device (60).

[0027] Preferably, the culture tanks of the sub-culturers (20) are not shown in FIG. 1, but can be provided in the form of a visual work of art, that is, a sculpture, that adds aesthetic value beyond the function of simply cultivating microalgae and harmonizes with the surrounding environment.

[0028] Here, the present invention does not specifically limit the configuration in which the main culture vessel (10) supplies the medium inoculated with microalgae to the sub-culture vessels (20). In other words, any configuration is acceptable as long as the main culture vessel (10) can supply the medium inoculated with microalgae to the sub-culture vessels (20).

[0029] In addition, the present invention does not specifically limit the configuration in which the main culture vessel (10) and the sub-culture vessel (20) supply the culture medium in which microalgae are cultured to the centrifugal type automatic microalgae harvesting device (100) according to the present invention. That is, any configuration is acceptable as long as the main culture vessel (10) and the sub-culture vessel (20) can supply the culture medium in which microalgae are cultured to the centrifugal type automatic microalgae harvesting device (100) according to the present invention without interfering with each other.

[0030] FIG. 2 is a drawing showing a centrifugal microalgae automatic harvesting device according to the present invention. The centrifugal microalgae automatic harvesting device (100) according to the present invention includes a centrifugal chamber (110), a harvesting drum (140), and a harvesting motor (130).

[0031] The centrifugation chamber (110) temporarily stores culture medium in which microalgae are cultured, supplied from the main culture vessel (10) or sub-culture vessel (20), so that microalgae can be harvested.

[0032] The centrifugal separation chamber (110) is formed in the shape of a hollow enclosure with an open top and a closed bottom, and as illustrated, the closed bottom side of the centrifugal separation chamber (110) is mounted and supported on a frame (112).

[0033] The open upper portion of the centrifugation chamber (110) is selectively opened and closed by a cover (114) so ​​that microalgae separated from the culture medium can be harvested.

[0034] And, adjacent to the upper and lower sides of the centrifugation chamber (110), a culture medium supply pipe (116) to supply culture medium in which microalgae have been cultured and a culture medium circulation pipe (118) to circulate culture medium in which microalgae have been separated to the main culture vessel (10) or sub-culture vessel (20) are installed.

[0035] Here, although not shown, an electric valve is installed in the culture medium supply pipe (116) and the culture medium circulation pipe (118) to open and close the flow path of the culture medium supply pipe (116) and the culture medium circulation pipe (118).

[0036] Meanwhile, an upper water level sensor (120) and a lower water level sensor (122) are installed on the upper and lower sides of the centrifugal separation chamber (110), respectively, so as not to interfere with the culture medium supply pipe (116) and the culture medium circulation pipe (118).

[0037] The upper water level sensor (120) prevents the maximum allowable amount of culture medium in which microalgae are cultured and supplied into the centrifugation chamber (110), and the lower water level sensor (122) prevents the amount of culture medium in which microalgae are cultured inside the centrifugation chamber (110) from falling below the minimum allowable amount.

[0038] For example, when the upper water level sensor (120) detects the culture medium in which microalgae are cultured supplied into the centrifugation chamber (110), the upper water level sensor (120) detects this and outputs a signal to the control unit (not shown), and the control unit closes the flow path of the culture medium supply pipe (116) so that the culture medium in which microalgae are cultured is not supplied.

[0039] For example, when the culture medium in which microalgae are cultured is detected by the lower water level sensor (122), the lower water level sensor (122) detects this and outputs a signal to the control unit (not shown), and the control unit opens the flow path of the culture medium supply pipe (116) so that the culture medium in which microalgae are cultured is supplied into the centrifugal chamber (110).

[0040] Preferably, the centrifugation chamber (110) may be formed to be transparent or translucent so that the operator can visually check the harvesting status of the microalgae.

[0041] The harvesting motor (130) is installed in the frame (112) so as not to interfere with the centrifugal separation chamber (110) and provides centrifugal force rotating at a high speed required for harvesting microalgae into the centrifugal separation chamber (110).

[0042] To this end, the harvesting motor (130) includes a centrifugal shaft (134) that receives the rotational force of the drive shaft (132) of the harvesting motor (130) and generates centrifugal force.

[0043] The centrifugal shaft (134) is installed vertically and rotatably through the closed lower center of the centrifugal chamber (110) as illustrated so as to transmit centrifugal force into the interior of the centrifugal chamber (110).

[0044] And the lower end of the centrifugal shaft (134) that penetrates the closed lower part of the centrifugal separation chamber (110) is connected to the drive shaft (132) of the harvesting motor (130) via power transmission elements, such as a belt and a pulley.

[0045] The harvesting drum (140) is installed inside the centrifugal chamber (110) and receives centrifugal force from the harvesting motor (130) to harvest microalgae.

[0046] The harvesting drum (140) is provided with a size that can be accommodated inside the centrifugal chamber (110), and the harvesting drum (140) is formed in the shape of a hollow enclosure with an open top and a closed bottom.

[0047] At this time, the culture medium containing cultured microalgae supplied through the culture medium supply pipe (116) is supplied into the interior of the harvest drum (140) through the open top of the harvest drum (140), and the culture medium containing cultured microalgae supplied into the interior of the harvest drum (140) is temporarily stored when filled into the interior of the centrifugation chamber (110).

[0048] And the closed lower part of the harvest drum (140) is detachably connected to the upper part of the centrifugal shaft (134) that extends into the interior of the centrifugal chamber (110), and the wall part (142) of the harvest drum (140) is formed in the shape of a fine filter mesh of 450 to 500 mesh so as to effectively capture microalgae.

[0049] Of course, the harvest drum (140) can be formed into a fine filter mesh of a suitable mesh depending on the spawn.

[0050] That is, when the culture medium in which microalgae are cultured is supplied to the inside of the harvest drum (140) through the culture medium supply pipe (116) from the side of the main culture medium (10) or sub culture medium (20), the harvest motor (130) rotates the centrifugal shaft (134) connected to the drive shaft (132) to rapidly rotate the harvest drum (140), and at this time, the microalgae inside the rapidly rotating harvest drum (140) are captured on the wall (142) of the harvest drum (140) by centrifugal force.

[0051] Then, the culture medium from which the microalgae have been separated flows out of the harvest drum (140) and is supplied to the main culture medium (10) or sub culture medium (20) through the culture medium circulation pipe (118).

[0052] Here, on the side of the main culture vessel (10) or sub culture vessel (20), a culture medium in which microalgae have been cultured can be supplied several times through the culture medium supply pipe (116), and likewise, the centrifugal microalgae automatic harvesting device (100) according to the present invention can supply the culture medium in which microalgae have been separated to the main culture vessel (10) or sub culture vessel (20) several times through the culture medium circulation pipe (118).

[0053] Meanwhile, when the microalgae harvesting is completed, the flow path of the culture medium supply pipe (116) is closed, and the operation of the harvesting motor (130) is stopped, and the cover (114) is opened to harvest the microalgae collected on the wall (142) of the harvesting drum (140).

[0054] For example, when harvesting microalgae, the harvest target can be set to 90% to harvest the microalgae, so that 10% of the microalgae inoculum is left in the main culture tank (10) or sub culture tank (20) for the next cultivation. In addition, the above-mentioned harvest target can be achieved by a turbidity sensor (12, 22) installed in the main culture tank (10) or sub culture tank (20), or installed in a flow path that guides the culture medium in which microalgae are cultured from the main culture tank (10) or sub culture tank (20) toward the centrifugal type automatic microalgae harvesting device (100).

[0055] FIG. 1 shows a state in which turbidity sensors (12, 22) are installed in the main culture tank (10) and the sub culture tank (20).

[0056] For example, when the turbidity of the culture medium in which microalgae are cultured in the main culture medium (10) or sub culture medium (20) reaches a preset maximum turbidity value, the culture medium in which microalgae are cultured in the main culture medium (10) or sub culture medium (20) is continuously supplied to the centrifugal type microalgae automatic harvesting device (100) according to the present invention so that microalgae are harvested from the culture medium in which microalgae are cultured in the main culture medium (10) or sub culture medium (20), and when the turbidity reaches a preset minimum turbidity value (10% relative to the maximum turbidity value) by the culture medium in which microalgae are separated and continuously supplied from the centrifugal type microalgae automatic harvesting device (100) according to the present invention, the main culture medium (10) or sub culture medium (20) cultures microalgae while blocking the supply of the culture medium in which microalgae are cultured to the centrifugal type microalgae automatic harvesting device (100) according to the present invention.

[0057] The centrifugal type automatic microalgae harvesting device (100) according to the present invention formed in this manner utilizes centrifugal force rotating at a high speed to separate the microalgae from the culture medium in which the microalgae are cultured, thereby harvesting the microalgae and significantly reducing the time and labor required for microalgae harvesting.

[0058] It is stated that the intrinsic technical concept of the present invention is not limited to the embodiments described above, but encompasses a scope that can be easily proposed by a person skilled in the art through substitution or modification.

[0059] Furthermore, since the terms used in the description of the present invention are selected for the convenience of explanation, in grasping the intrinsic technical concept of the present invention, they should not be limited to their dictionary meanings but should be appropriately interpreted in a sense consistent with the technical concept of the present invention.

Claims

1. A centrifugal chamber for temporarily storing a culture medium in which microalgae are cultured, supplied from a main culture medium or a sub-culture medium; a harvesting motor for providing centrifugal force rotating at a high speed required for harvesting microalgae into the centrifugal chamber; and a harvesting drum installed inside the centrifugal chamber, which receives the culture medium in which microalgae are cultured into the interior, and receives centrifugal force from the harvesting motor to separate the microalgae from the culture medium and capture and harvest the microalgae; wherein The above centrifugal chamber is formed in the shape of a hollow vessel with an open top and a closed bottom, the closed bottom side is mounted and supported on a frame, the open top of the centrifugal chamber is selectively opened and closed by a cover to harvest microalgae separated from the culture medium, and a culture medium supply pipe for supplying the culture medium in which microalgae are cultured and a culture medium circulation pipe for directly circulating the culture medium in which microalgae are separated to the main culture medium or the sub-culture medium are installed adjacent to the top and bottom sides of the centrifugal chamber, respectively. An upper water level sensor and a lower water level sensor are installed on the upper and lower sides of the centrifugal separation chamber, respectively; the upper water level sensor detects the maximum allowable level and cuts off the supply, and the lower water level sensor prevents the level from falling below the minimum allowable level to maintain stable centrifugal force of the harvesting motor. A centrifugal type automatic microalgae harvesting device characterized by the following: a turbidity sensor is installed in the path guiding the main culture vessel, the sub culture vessels, or the culture medium in which microalgae are cultured to the centrifugal type automatic microalgae harvesting device; the turbidity sensors supply the culture medium to the centrifugal chamber when the turbidity of the culture medium reaches a preset maximum turbidity value, and automatically leave a starter culture for the next cultivation by blocking the supply of the microalgae culture medium when the turbidity sensors reach 10% of the preset maximum turbidity value; and the separated culture medium circulation through the culture medium circulation pipe and the upper / lower water level sensor control are linked to automatically perform a continuous harvesting and cultivation cycle.

2. In Claim 1, The above centrifugal separation chamber is formed to be transparent or translucent. Centrifugal type automatic microalgae harvesting device.

3. In Claim 1, The above harvesting motor is installed on the frame, and The above harvesting motor is a centrifugal motor that receives rotational force from the drive shaft and generates centrifugal force. Includes the axis; but, The centrifugal shaft is installed to rotatably pass through the closed lower center of the centrifugal separation chamber, and the centrifugal shaft passing through the closed lower part of the centrifugal separation chamber The lower part is a centrifugal type automatic microalgae harvesting device connected to the drive shaft of the harvesting motor and a power transmission element.

4. In Claim 3, The above-mentioned harvesting drum is formed in the shape of a hollow container with an open top and a closed bottom, and The closed lower part of the harvesting drum is detachably connected to the upper end of the centrifugal shaft extending into the interior of the centrifugal separation chamber, and A centrifugal type automatic microalgae harvesting device in which the wall of the harvesting drum is formed in the shape of a filter mesh to capture microalgae.

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