CN101597564A - Microalgae harvesting method, system and microalgae harvester - Google Patents

Abstract

The invention discloses a microalgae harvesting method, system and microalgae harvester, which are used for microalgae harvesting in a microalgae cultivation device. The orbital movement set on the device filters and collects the microalgae in the algae liquid through the harvesting device installed under it, and enriches the microalgae into the selected area in the microalgae cultivation device; and the collection place of the microalgae harvesting vehicle The microalgae in the selected area in the microalgae cultivation device is enriched with algae liquid. The above microalgae harvesting method can enrich and collect microalgae in a small area, and only need to collect the microalgae-enriched liquid in a selected area of the microalgae harvesting device. Because the harvesting system moves slowly, there is no need to circulate liquid, which reduces the work intensity, reduces energy consumption, and improves work efficiency.

Description

Microalgae harvesting method, system and microalgae harvester

technical field

The invention relates to the field of biotechnology, in particular to a low-cost and automatic microalgae harvesting method, system and microalgae harvester for harvesting microalgae cultured in a microalgae cultivation device.

Background technique

In recent years, the frequent occurrence of red tides, the massive flooding of microalgae in lakes, and the emergence of large-scale microalgae cultivation have made the treatment, harvesting and processing of microalgae a hot topic in current research. The commonly used harvesting methods are:

(1) Filtration method

Australian Patent Application No. 486999 discloses a filtration method for recovering algal bodies from a suspension of microalgae. The specific steps are: add the deliberation aid to the algae suspension before filtering, and then recover the deliberation aid and the algae by high-pressure filtration; separate the algae from the deliberation aid, and the algae enters the next extraction process, and the deliberation aid is recycled.

The application number is the microalgae harvesting method disclosed in the patent application WO9828403A1, specifically: after the algae cells are broken, the brine is pumped into the microporous filter membrane without flocculant, the algae body concentrate is intercepted, and the brine passing through the membrane does not Contains carotene, therefore, multi-stage filtration can be used to adjust the salt and carotenoid concentration in the retentate.

Filtration is a commonly used and mature chemical method, but because the density of the microalgae suspension is too low, it takes a lot of energy to pump the algae liquid into the filter device to achieve the purpose of filtration and separation, and the cost is too high.

(2) centrifugal separation method

Centrifugal separation is a forced mechanical separation method commonly used in biological separation. At present, the disc centrifugal separator with automatic slag unloading is widely used in the separation of microalgae, which is easy to operate and can work continuously.

But this separation method also needs to pump a large amount of algae liquid into the centrifuge, and the energy consumption of the centrifuge is almost the highest of all separation equipment. This separation method causes the energy consumption of microalgae harvesting to account for almost 1/3-1/2 of the cost of microalgae cultivation.

(3) Chemical flocculation method

Microbial Resources Company in the United States adopts the flocculation and sedimentation method to enrich Salina salina. Each intensive culture cycle uses a newly prepared salt solution. A certain proportion of flocculant, flocculation and sedimentation of salina; the absorption pipe is directly extended to the conical bottom of the sedimentation tank to vacuum the sedimentation algae mud.

Another improved application of the flocculation method is: after pumping the algae solution into the air flotation tank, adding a flocculant to flocculate the microalgae, and then passing gas at the bottom of the air flotation tank, so that the flocculated microalgae are suspended with the algae under the action of gas carrying. Liquid surface for easy collection. This is the so-called air flotation method.

Both flocculation and air flotation are common chemical separation methods, and have a wide range of applications in the chemical industry, but their application in microalgae collection still needs further research. Moreover, the flocculation method generally needs to introduce the algae liquid into a special sedimentation tank or air flotation tank, and then harvest the microalgae. In this process, there is still the energy consumption of using pumps to transport the algae liquid, and the choice of flocculant is very critical. Ordinary flocculants are likely to cause damage to microalgae.

(4) Electric field flocculation

Electric field flocculation is an improvement of ordinary flocculation. Salina cells generally have weakly negative charges on their surfaces in aqueous media. When these charged particles are balanced by the surrounding liquid film, capacitance may form between two adjacent particles. Under the action of an external electric field, this balance is easily broken, so the algal cells aggregate and form large flocs on the surface of the carrier, thereby realizing the collection of microalgae.

However, the use of the electric field flocculation method has limitations, and not all microalgae have certain electrical properties, so this method is not universal.

(5) New technologies such as microfiltration and ultrafiltration

New technologies such as microfiltration and ultrafiltration are currently being tried to be applied to the microalgae harvesting process, but most of them are still in the experimental stage, and there is no possibility of large-scale use for the time being.

The commonly used method for harvesting the above-mentioned microalgae is to pump out the algae liquid and collect the microalgae by filtration. , the way to filter the collection. Due to the relatively low density of the cultured microalgae and microalgae, when circulating the algae liquid and collecting the microalgae through the filter, a large amount of algae liquid is circulated by the pump, resulting in a heavy workload and a lot of energy consumption during the harvesting process. , causing the fixed cost of microalgae harvest to be too high, thus affecting the reduction of microalgae production cost. At present, there are problems such as low yield and high cost in the microalgae cultivation and production process, and its high production cost is mostly caused by the high cost of microalgae harvesting.

And the above-mentioned problems such as adopting the applicable surface of flocculation method are relatively narrow again, can not reach problems such as ideal harvesting effect.

Contents of the invention

The embodiments of the present invention provide a microalgae harvesting method, system and microalgae harvester, which solve the problems in the prior art of microalgae production, high harvesting costs, and large energy consumption.

A microalgae harvester, comprising: a frame, a driving device, a harvesting device and at least one set of wheels;

The driving device is installed on the frame and is used to provide power to a group of wheels connected to itself;

The harvesting device is fixedly installed under the frame, and is used to filter and collect the microalgae in the algae liquid, and enrich the microalgae into a selected area in the microalgae cultivation device;

The wheels are fixedly installed under the frame; wherein at least one set of wheels is connected to the driving device and rotates under the power provided by the driving device; the harvesting device is driven by the rotation of the wheels Moving along the track set on the microalgae cultivation device, the microalgae in the algae liquid can be enriched in the selected area of the microalgae cultivation device.

The above-mentioned microalgae harvester of the present invention, the harvesting device includes: a harvesting tool and a filter screen;

The harvesting tool is fixedly installed under the frame;

The filter screen, installed on the harvesting tool, is used to filter the microalgae in the algae liquid when moving with the harvesting tool, and enrich the microalgae into a selected area in the microalgae cultivation device .

In the above-mentioned microalgae harvester of the present invention, the drive device includes: a power device and a transmission device;

The transmission device is fixedly installed in the middle cavity of the frame, and is connected with the power device fixedly installed above the frame; and transmits the power provided by the power device to a connected to itself set of wheels.

In the above-mentioned microalgae harvester of the present invention, the transmission device includes: a belt and two pulleys;

The two pulleys are installed in the middle cavity of the frame, wherein one pulley is connected with the power device, and the other pulley is connected coaxially with a group of wheels;

The belt and the two pulleys form a belt transmission mechanism, which drives the wheels to rotate.

In the above-mentioned microalgae harvester of the present invention, the transmission device further includes: a worm wheel and a worm;

The worm wheel and the worm are installed in the middle cavity of the frame; the worm is connected with the power device, and the worm wheel is connected with the one pulley to realize power transmission.

In the microalgae harvester of the present invention, the shape and size of the harvesting tool are determined by the cross-sectional shape of the microalgae cultivation device and the suspension state of the microalgae; specifically, it includes:

If the microalgae are suspended and distributed in the algae liquid, the size of the harvesting tool is equal to or slightly smaller than the size of the cross section of the microalgae cultivation device, and the shape is the same as the cross section;

If the microalgae floats on the surface of the algae liquid or sinks at the bottom of the algae liquid, the size and shape of the harvesting tool are determined by the height of the distribution area of the microalgae and the cross-sectional shape of the microalgae cultivation device within the height range.

In the microalgae harvester of the present invention, the harvesting tool has flexible materials on both sides and bottom, which are used to clean the side wall and bottom of the microalgae cultivation device when moving with the harvesting tool.

In the microalgae harvester of the present invention, the mesh aperture size of the filter mesh ranges from 1 μm to 1000 μm, and filters with different mesh apertures are selected according to the type and/or size of the microalgae.

The above-mentioned microalgae harvester of the present invention also includes:

The guide part is installed on the front or rear outer wall of the frame, and is used to ensure that the microalgae harvester moves along the track provided on the microalgae cultivation device.

A microalgae harvesting system, comprising: a microalgae cultivation device, a microalgae harvester and a microalgae harvester;

The microalgae cultivation device is used to hold the algae liquid containing microalgae, and a track is arranged on it;

The microalgae harvester is used to move along the track provided on the microalgae cultivation device, and filter and collect the microalgae in the algae liquid through the harvesting device provided below it, so as to enrich the microalgae into the microalgae culture within a selected area of the device;

The microalgae harvesting vehicle is used for collecting microalgae-enriched algae liquid in a selected area of the microalgae cultivation device.

The microalgae harvesting system of the present invention, the microalgae harvester includes: a frame driving device, a harvesting device and at least one set of wheels;

The driving device is installed on the frame and is used to provide power to a group of wheels connected to itself;

The harvesting device is fixedly installed under the frame, and is used to filter and collect the microalgae in the algae liquid, and enrich the microalgae into a selected area in the microalgae cultivation device;

The wheels are fixedly installed under the frame; wherein at least one set of wheels is connected to the driving device and rotates under the power provided by the driving device; the harvesting device is driven by the rotation of the wheels Moving along the track set on the microalgae cultivation device, the microalgae in the algae liquid can be enriched in the selected area of the microalgae cultivation device.

In the above-mentioned microalgae harvesting system of the present invention, the harvesting device included in the microalgae harvester includes: a harvesting tool and a filter screen;

The harvesting tool is fixedly installed under the frame;

The filter screen, installed on the harvesting tool, is used to filter the microalgae in the algae liquid when moving with the harvesting tool, and enrich the microalgae into a selected area in the microalgae cultivation device .

In the above-mentioned microalgae harvesting system of the present invention, the driving device included in the microalgae harvesting machine includes: a power device and a transmission device;

The transmission device is fixedly installed in the middle cavity of the frame, and is connected with the power device fixedly installed above the frame; and transmits the power provided by the power device to a connected to itself set of wheels.

1 The above-mentioned microalgae harvesting system of the present invention, the microalgae harvester also includes:

The guide part is installed on the front or rear outer wall of the frame, and is used to ensure that the microalgae harvester moves along the track provided on the microalgae cultivation device.

In the above-mentioned microalgae harvesting system of the present invention, the shape and size of the harvesting tool are determined by the cross-sectional shape of the microalgae cultivation device and the suspension state of the microalgae; specifically include:

If the microalgae are suspended and distributed in the algae liquid, the size of the harvesting tool is equal to or slightly smaller than the size of the cross section of the microalgae cultivation device, and the shape is the same as the cross section;

If the microalgae floats on the surface of the algae liquid or sinks at the bottom of the algae liquid, the size and shape of the harvesting tool are determined by the height of the distribution area of the microalgae and the cross-sectional shape of the microalgae cultivation device within the height range.

In the above microalgae harvesting system of the present invention, the harvesting tool installed on the microalgae harvesting machine has flexible materials on both sides and bottom, which are used to clean the side wall and bottom surface of the microalgae cultivation device when moving with the harvesting tool.

In the above-mentioned microalgae harvesting system of the present invention, the value range of the mesh aperture size of the filter screen installed on the microalgae harvester is 1 μm to 1000 μm, specifically according to the type of microalgae and/or the size of the microalgae. A filter with a mesh aperture.

In the microalgae harvesting system of the present invention, the microalgae harvesting vehicle includes: a harvesting pump, a vehicle-mounted small settling tank and an ordinary vehicle body;

The harvesting pump is used to extract the microalgae-enriched algae liquid in the selected area of the microalgae cultivation device;

The vehicle-mounted small settling tank is used to store the microalgae-enriched algae liquid pumped out by the harvesting pump;

The common car body is used as the carrier of the harvest pump and the vehicle-mounted small sedimentation tank, so that the harvest pump and the vehicle-mounted small sedimentation tank can move between multiple microalgae cultivation devices.

The above-mentioned microalgae harvesting system of the present invention also includes:

The filtration and dehydration system is used for filtering and dehydrating the microalgae-enriched liquid transported by the microalgae harvesting vehicle to obtain a dehydrated algae cake.

A method for harvesting microalgae, comprising:

The microalgae harvester moves along the track set on the microalgae culture device containing the microalgae liquid, and through the harvesting device installed below it, collects the microalgae in the algae liquid by filtration, and enriches the microalgae into the microalgae within selected areas of the culture device; and

The microalgae harvesting vehicle collects the microalgae-enriched algae liquid in the selected area of the microalgae cultivation device.

According to the above microalgae harvesting method of the present invention, the shape and size of the harvesting tool are determined by the cross-sectional shape of the microalgae cultivation device and the suspension state of the microalgae; specifically include:

If the microalgae are suspended and distributed in the algae liquid, the size of the harvesting tool is equal to or slightly smaller than the size of the cross section of the microalgae cultivation device, and the shape is the same as the cross section;

If the microalgae floats on the surface of the algae liquid or sinks at the bottom of the algae liquid, the size and shape of the harvesting tool are determined by the height of the distribution area of the microalgae and the cross-sectional shape of the microalgae cultivation device within the height range.

The above-mentioned microalgae harvesting method of the present invention also includes:

The microalgae harvester is provided with guide components to ensure its movement along the track provided on the microalgae cultivation device.

According to the method for harvesting microalgae of the present invention, flexible materials are fixedly installed on both sides and bottom of the harvesting tool, and when moving with the harvesting tool, the side wall and bottom surface of the microalgae cultivation device are cleaned.

In the above-mentioned method for harvesting microalgae of the present invention, filter screens with different mesh apertures are selected according to the type of microalgae and/or the size of the microalgae;

The value range of the mesh aperture of the filter screen is 1 μm˜1000 μm.

According to the above microalgae harvesting method of the present invention, the microalgae harvesting vehicle collects the microalgae-enriched algae liquid in the selected area of the microalgae cultivation device, specifically comprising:

The harvesting pump installed on the microalgae harvesting vehicle pumps out the microalgae-enriched liquid in the selected area of the microalgae cultivation device, and stores it in the vehicle-mounted small settling tank installed on the microalgae harvesting vehicle.

According to the above-mentioned microalgae harvesting method of the present invention, when there are multiple microalgae cultivation devices, the microalgae harvesting vehicle moves between multiple microalgae cultivation devices, and collects selected The microalgae in the area enrich the algae liquid.

The above-mentioned microalgae harvesting method of the present invention also includes:

The filtration and dehydration system filters and dehydrates the microalgae-enriched liquid transported by the microalgae harvesting vehicle to obtain a dehydrated algae cake.

The microalgae harvesting method, system and microalgae harvester provided in the embodiments of the present invention. The microalgae harvester moves along the track set on the microalgae culture device containing the microalgae liquid, and through the harvesting device installed below it, collects the microalgae in the algae liquid by filtration, and enriches the microalgae into the microalgae culture device In the selected area; and the microalgae harvesting vehicle collects the microalgae-enriched algae liquid in the selected area in the microalgae cultivation device. The above microalgae harvesting method can enrich and collect microalgae in a small area, increase the concentration of microalgae in the algae liquid in this small area, thereby reducing the amount of algae liquid that needs to be pumped out when collecting algae liquid ; When the method harvests microalgae, it only needs to collect the microalgae-enriched algae liquid enriched in the selected area of the microalgae harvesting device, without circulating the algae liquid, which reduces the work intensity, reduces energy consumption, and improves work efficiency. efficiency. By using the filter screen, it is possible to enrich the microalgae in a small area, and to keep the algae species while continuing to cultivate and reproduce. The design of the microalgae harvesting vehicle realizes the collection of a group of equipment for the collection of microalgae-enriched algae liquid in multiple places. Through the mobility of the microalgae harvesting vehicle, the utilization rate of the equipment is improved and the one-time investment of fixed costs is reduced.

Description of drawings

Fig. 1 is the structural representation of microalgae harvesting system in the embodiment of the present invention;

Fig. 2 is the structural representation of microalgae harvester and microalgae cultivation device in the embodiment of the present invention

Fig. 3 is a kind of specific structure schematic diagram of microalgae harvester in the embodiment of the present invention;

Fig. 4 is a partially enlarged view after rotation of Fig. 2 in an embodiment of the present invention;

Fig. 5 is a structural schematic diagram of installing a worm gear in an embodiment of the present invention;

Fig. 6 is a flow chart of the microalgae harvesting method in the embodiment of the present invention.

Detailed ways

If the microalgae can be harvested in a timely manner during the growth process, on the one hand, it can eliminate the density suppression in the process of microalgae reproduction to a certain extent and maintain high-density cultivation; Harvesting is also conducive to the continuity requirements of industrialization.

The microalgae harvesting method, system and microalgae harvester provided by the embodiments of the present invention aim at pumping out the algae liquid in the prior art, and the circulation and filtration of a large amount of algae liquid leads to large energy consumption. Features, design a microalgae harvester to be used in conjunction with it, through the use of the microalgae harvester, the microalgae is concentrated in a small area, and then concentrated for filtration and collection. Reduce the algae liquid that is pumped out and circulated and filtered, thereby reducing energy consumption and reducing costs.

The microalgae harvesting system provided by the embodiment of the present invention, as shown in FIG. 1 , includes: a microalgae cultivation device 10 , a microalgae harvester 20 and a microalgae harvesting vehicle 30 . The structures of the microalgae cultivation device 10 and the microalgae harvester 20 are shown in FIG. 2 , wherein the microalgae harvester 20 is used in the microalgae cultivation device 10 .

The microalgae cultivating device 10 is used to contain the algae solution containing microalgae, and tracks are provided on the upper surface, bottom or other positions, especially, parallel tracks can be used. The microalgae harvester 20 can move along the track provided. The microalgae cultivation device 10 can be used as a microalgae cultivation container for the cultivation of microalgae. The microalgae cultivation device 10 may include various devices for microalgae cultivation such as photoreactors and culture ponds.

The microalgae harvester 20 is used to move along the parallel track on the upper surface of the microalgae cultivation device 10, and filter and collect the microalgae in the algae liquid through the harvesting device arranged below it, so as to enrich the microalgae into the microalgae cultivation device 10 within the selected area. Wherein, the selected area may be one end of the microalgae cultivation device 10 , or any small section in the middle of the microalgae cultivation device 10 .

In particular, microalgae harvesters 20 of different sizes and widths can be designed according to the width of the microalgae cultivation device, and different harvesting tools and filter screens can be selected according to the size and shape of the cross section of the microalgae cultivation device.

The microalgae harvester 20 can move in the microalgae cultivating device 10 along the track provided on the microalgae cultivating device 10 (when the selected area is one end, then slowly move from one end of the microalgae cultivating device 10 to the distance set at the other end distance), so as to realize the enrichment of the algae liquid into the selected area of the microalgae cultivation device 10. In particular, it can also be enriched in a certain small area in the middle of the microalgae cultivation device 10 . That is, after obtaining a high-concentration microalgae liquid, it is collected.

The microalgae harvesting vehicle 30 is used to collect the microalgae-enriched algae liquid in the selected area of the microalgae cultivation device 10 .

The above-mentioned microalgae harvesting system further includes: a filtration and dehydration system 40 for filtering and dehydrating the microalgae-enriched liquid transported by the microalgae harvesting vehicle 30 to obtain a dehydrated algae cake.

Filtration and dehydration system 40 mainly includes several equipments such as belt vacuum filter, algae cake recovery device and so on. The belt vacuum filter is purchased in the market, which can realize the continuous solid-liquid separation of microalgae and liquid. The algae cake recovery device is mainly used to collect algae cakes and obtain other microalgae substances. The belt vacuum filter suitable for microalgae harvesting is obtained by adding a micron filter cloth suitable for microalgae filtration on the basis of the ordinary belt vacuum filter; it has been improved on the original basis to increase the vibration , Flushing function, effectively prevent microalgae from clogging the filter cloth.

Filtration dehydration system 40 is a place for producing microalgae biomass. The microalgae-enriched algae liquid collected in the microalgae harvesting vehicle is transported to the microalgae filtration and dehydration system, and the microalgae-enriched algae liquid is evenly distributed on the surface of the filter system of the belt vacuum filter, and the track is rotated by the motor to enrich the microalgae. The algae collection liquid is filtered and concentrated with the movement of the track, and the concentrated algae cake is scraped off by the scraper to the algae cake recovery device, and then the development of microalgae products is carried out.

The above-mentioned microalgae harvester 20 may include: a frame, a driving device, a harvesting device and at least one set of wheels. in:

The drive unit is mounted on the frame and is used to power a set of wheels connected to itself.

Preferably, the driving device may further include: a power device and a transmission device; the transmission device is fixedly installed in the middle cavity of the frame, and is connected with the power device fixedly installed on the top of the frame; and the power transmission provided by the power device Gives a set of wheels connected to itself.

In particular, the drive device may only include a power device, and the power device is directly connected to a group of wheels to directly drive the wheels to rotate.

The harvesting device is fixedly installed under the frame, and is used for filtering and collecting the microalgae in the algae liquid, and enriching the microalgae into a selected area in the microalgae cultivation device.

Preferably, the harvesting device may further include: harvesting tools and filter screens.

The harvesting tool is fixedly installed under the frame. Wherein, the shape and size of the harvesting tool are determined by the cross-sectional shape of the microalgae cultivation device 10 and the suspended state of the microalgae; specifically include:

If the microalgae is suspended and distributed in the algae liquid, the size of the harvesting tool is equal to or slightly smaller than the size of the cross section of the microalgae cultivation device 10, and the shape is the same as the cross section; The side walls of the culture device 10 cooperate with the bottom surface.

If the microalgae floats on the surface of the algae liquid or sinks at the bottom of the algae liquid, the size and shape of the harvesting tool are determined by the height of the distribution area of the microalgae and the cross-sectional shape of the microalgae cultivation device within the height range. When the harvesting tool moves in the microalgae cultivation device, it cooperates with the side wall of the microalgae cultivation device 10, or cooperates with the side wall and the bottom surface.

The filter screen is installed on the harvesting tool, and is used for filtering the microalgae in the algae liquid when moving with the harvesting tool, and enriching the microalgae into a selected area in the microalgae cultivation device.

The wheels are fixedly installed under the frame; at least one set of wheels is connected with the driving device and rotates under the power provided by the driving device; Enrich the microalgae in the algae liquid into the selected area in the microalgae cultivation device.

As shown in Figure 3, it is a specific structure of the microalgae harvester, including: frame 21, power unit 22, transmission device 23, harvesting tool 24, filter screen 25 and two groups of wheels (26,27). Among them, FIG. 4 is a partially rotated enlarged view of the upper part of FIG. 3 . Wherein the power device 22 and the transmission device 23 jointly form a driving device; the harvesting tool 24 and the filter screen 25 jointly form a harvesting device.

The power device 22 is fixedly installed above the frame 21 and connected with the transmission device 23 . It provides a source of power for the movement of the microalgae harvester. For example, the power unit can be a geared motor or the like.

The transmission device 23 is fixedly installed in the middle cavity of the frame 21, and is respectively connected with the power device 22 and a group of wheels 26; it is used to transmit the power provided by the power device 22 to the above-mentioned group of wheels 26 connected with itself. The machine transmission device 23 can realize energy conversion, and the energy output of the power device is converted into the kinetic energy of the harvesting tool.

Preferably, the transmission device 23 includes: two pulleys (231, 232) and a belt 233.

Both pulleys ( 231 , 232 ) are installed in the middle cavity of the frame 21 , wherein one pulley 231 is connected with the power unit 22 , and the other pulley 232 is connected with a group of wheels 26 coaxially.

The belt 233 and two pulleys (231, 232) form a belt transmission mechanism, which drives the wheels to rotate.

Preferably, as shown in FIG. 5 , the transmission device 23 may further include: a worm wheel 234 and a worm 235 .

Worm wheel 234 and worm screw 235 are installed in the middle cavity of frame 21; worm screw 235 is connected with power unit 22, and worm wheel 234 is connected with pulley 231 again, realizes the transmission of power. The power is transmitted through the worm gear, which can increase the torque and further reduce energy consumption.

It should be noted that: the transmission device 23 can adopt various common mechanical transmission mechanisms, for example, belt transmission, gear transmission, worm gear transmission and combinations thereof. Fig. 3 and Fig. 4 are the best embodiment of the present invention, wherein the two-stage combination of worm gear and worm gear and belt drive is adopted. Therefore, it can be understood that only the belt drive is also possible.

The harvesting tool 24 is fixedly installed below the frame 21 and is located in the middle of two groups of wheels (26, 27); The bottom surfaces have a small gap or contact and move with friction, or only a small gap or contact with the side walls and move with friction. A filter screen 25 is installed on the harvesting tool 24, and the filter screen 25 is a net-like structure material, and the mesh size varies according to the algae species collected.

The harvesting tool 24 can be designed or selected in different structures according to the shape of the microalgae cultivating device 10 . In FIGS. 2 and 3 , only a rectangular frame is used as an example for illustration. There are flexible materials on both sides and bottom of the harvesting tool 24, which are fixedly connected with the harvesting tool 24, and are used for cleaning the side wall and the bottom surface of the microalgae cultivation device 10 when moving with the harvesting tool 24.

Filter screens with different mesh apertures are selected according to the species of microalgae and/or the size of the microalgae. For example: the optional range of the mesh size of the filter 25 includes 1 μm˜1000 μm. Preferably, the filter screen 25 can adopt a self-rinsing frame filter screen; at the same time, when selecting the filter screen, it can be considered that it is not necessary to completely collect the microalgae in the algae liquid, and about 1/3 of the residue can be allowed to be used as a microalgae for further cultivation. Algae species, in order to facilitate the continuation of microalgae culture.

Two groups of wheels (26, 27) are fixedly installed at the front and rear ends of the bottom of the frame 21 respectively. Wherein, a set of wheels 26 is connected with the transmission device 23 and rotates under the power transmitted by the transmission device 23 . The other set of wheels are driven wheels, which rotate with the rotation of the driving wheels. The rotation of the two sets of wheels (26, 27) drives the harvesting tool 24 and the filter screen 25 on it to move, enriching the microalgae in the algae solution into the selected area of the microalgae cultivation device 10.

In particular, the above-mentioned microalgae harvester also includes: a guide part 28, which is installed on the outer wall of the frame 21 outside the front or rear (a group of wheels 26 or 27 as shown in the figure), to ensure that the microalgae harvester 20 moves along the The track provided on the microalgae cultivation device 10 moves linearly. Wherein, the effective width of the guide member is equal to the distance between the two inner walls of the microalgae cultivation device 10 .

The microalgae harvesting vehicle 30 is mainly responsible for the transportation and settlement of microalgae-enriched algae liquid. It is transformed from an ordinary vehicle body, including: a harvesting pump, a small vehicle-mounted settling tank and an ordinary vehicle body.

The harvesting pump is used to extract the microalgae-enriched algae liquid in the selected area of the microalgae cultivation device 10 . The harvesting pump can be purchased from the market, fixed on the vehicle body, and can move with the vehicle body to pump the enriched algae liquid to the vehicle-mounted sedimentation tank

The vehicle-mounted small settling tank is used to store the microalgae-enriched algae liquid pumped out by the harvesting pump; the vehicle-mounted small settling tank is refitted from an ordinary settling tank, and is fixed on the car body for temporary storage and settlement of the enriched microalgae liquid. Preliminary solid-liquid separation can be achieved before being transported to the subsequent processing workshop, further saving energy consumption.

Ordinary car body, used as a carrier for the harvest pump and the on-board small settling tank. Transport the collected microalgae-enriched algae liquid to the dehydration system for filtration and dehydration;

Particularly, microalgae cultivating device 10 and microalgae harvesting machine 20 can arrange multiple sets, and microalgae harvesting vehicle 30 travels between a plurality of microalgae cultivating devices 10, and the harvesting pump and vehicle-mounted small settling tank are connected by microalgae harvesting vehicle 30 It can move between multiple microalgae cultivation devices 10 to realize the collection of microalgae-enriched algae liquid in multiple microalgae cultivation devices 10 .

Through the above-mentioned microalgae harvesting system provided by the embodiment of the present invention, the process flow of the microalgae harvesting method is shown in Figure 6, and the execution steps are as follows:

S101: the microalgae harvester will enrich the microalgae in the algae liquid into the selected area of the microalgae cultivation device. Specifically:

The microalgae harvester moves along the track set on the microalgae cultivation device containing the microalgae liquid, and through the harvesting device installed under the microalgae harvester, the microalgae in the algae liquid is filtered and collected, and the microalgae is enriched into the microalgae. In the selected area of the algae culture device.

For example, the microalgae harvester moves from one end of the microalgae cultivation device to the other end (reciprocating motion can be allowed during the moving process, and reciprocating motion can better prevent the mesh of the filter from clogging), and then it can stay at a distance of 1m from the other end. Left or right or other set distances to achieve microalgae enrichment, the concentration of the enriched algae liquid is significantly increased, and the next step is to reduce the workload of the microalgae liquid by about 90% or a set ratio, thereby greatly reducing the pump. The energy consumption of the algae solution. In particular, a baffle can be used to separate two parts of the algae liquid with different concentrations, and the shape of the baffle can be selected according to the cross-sectional shape of the microalgae cultivation device. For example, the rectangular sectional microalgae cultivation device in Fig. 2 uses a rectangular baffle.

When the harvesting tool moves in the microalgae cultivation device, according to the specific shape and size of the selected harvesting tool, it fits or fits closely with the small gap between the side wall and the bottom of the microalgae cultivation device and has friction when moving, or only between the side wall There is a small gap or contact and there is friction when moving. In particular, flexible materials are fixedly installed on both sides and bottom of the harvesting tool, so that it can closely cooperate with the side wall and bottom surface of the microalgae cultivation device, and when moving with the harvesting tool, the side wall and bottom surface of the microalgae cultivation device are cleaned.

Filters with different mesh apertures can be selected according to the type and/or size of the microalgae; for example, the mesh size of the selectable filter varies from 1 μm to 1000 μm.

A guide component is arranged on the microalgae harvester to ensure that the microalgae harvester can move along the track provided on the microalgae cultivation device.

S102: The microalgae harvesting vehicle collects the microalgae-enriched liquid in the selected area of the microalgae cultivation device. Specifically include:

The harvesting pump installed on the microalgae harvesting vehicle pumps out the microalgae-enriched algae liquid in the selected area of the microalgae cultivation device, and stores it in the vehicle-mounted small settling tank installed on the microalgae harvesting vehicle.

In particular, when there are multiple microalgae cultivating devices, the microalgae harvesting vehicle moves among the multiple microalgae cultivating devices, and collects microalgae-enriched algae liquid in selected areas of each microalgae cultivating device.

The above-mentioned microalgae harvesting method also includes:

S103: The microalgae harvesting vehicle transports the collected microalgae-enriched algae liquid to the filtration and dehydration system.

S104: The filtration and dehydration system filters and dehydrates the transported microalgae-enriched liquid to obtain a dehydrated algae cake.

The above microalgae harvesting method, system and microalgae harvesting machine provided in the embodiments of the present invention can realize automatic and low-cost microalgae collection. The microalgae harvester moves along the track set on the microalgae culture device containing the microalgae liquid, and through the harvesting device installed below it, collects the microalgae in the algae liquid by filtration, and enriches the microalgae into the microalgae culture device Collected by microalgae harvesting vehicles in selected areas. The above microalgae harvesting method can enrich and collect microalgae in a small area, greatly increasing the concentration of microalgae in the algae liquid in this small area, thereby reducing the volume of the algae liquid that needs to be pumped out when collecting the algae liquid. It avoids the circulating pumping and filtration collection of a large amount of algae liquid, reduces the work intensity and energy consumption, and improves the harvesting efficiency and speed. It effectively solves the problem of large-area microalgae cultivation, which is limited by the performance of the pump and requires a large number of high-power pumps to meet the industrial microalgae production problem.

The above microalgae harvesting method and system can realize fully automated microalgae harvesting operations. The microalgae harvester can automatically move along the wall of the microalgae cultivation device under the drive of the power device, without manual power, which further improves the microalgae harvesting. The efficiency and speed of algae harvesting, and its microalgae harvester moves slowly and consumes very little energy.

The microalgae harvesting machine is equipped with harvesting tools. By selecting the harvesting tools with the same size and shape as the cross-section of the microalgae cultivation device and using a filter, it is possible to enrich the microalgae in a small area and retain Under the algae, in order to facilitate the continued cultivation and reproduction of microalgae. And by selecting the self-flushing frame filter, the self-flushing of the filter is realized through reciprocating motion, effectively avoiding the blockage of the mesh. And for different algae species, filter screen meshes of different sizes can be selected, even when there are multiple types of microalgae in the same microalgae cultivation device, batches and selective harvesting of microalgae can be realized.

The design of the microalgae harvesting vehicle realizes the collection of a group of equipment for the collection of microalgae-enriched algae liquid in multiple places. Through the mobility of the microalgae harvesting vehicle, the utilization rate of the equipment is improved and the one-time investment of fixed costs is reduced.

Compared with the filtration and centrifugation methods introduced in the technical background, it can save energy by about 85%, greatly reducing production costs; compared with harvesting methods such as flocculation and air flotation, this method does not need to introduce additional chemicals and will not threaten the growth of algae ; Compared with the electric field flocculation method, this method is universally applicable and operable. For different microalgae, it is only necessary to change the type of filter screen and adjust the pore size of the filter screen to realize the collection of various types of microalgae.

The above is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any skilled person in the technical field can easily think of changes, Replacement or application to other similar devices shall fall within the protection scope of the present invention. Therefore, the protection scope of the present invention should be determined by the protection scope of the claims.

Claims (27)

1. A microalgae harvester, comprising: a frame, a driving device, a harvesting device and at least one set of wheels; The driving device is installed on the frame and is used to provide power to a group of wheels connected to itself; The harvesting device is fixedly installed under the frame, and is used to filter and collect the microalgae in the algae liquid, and enrich the microalgae into a selected area in the microalgae cultivation device; The wheels are fixedly installed under the frame; wherein at least one set of wheels is connected to the driving device and rotates under the power provided by the driving device; the harvesting device is driven by the rotation of the wheels Moving along the track set on the microalgae cultivation device, the microalgae in the algae liquid can be enriched in the selected area of the microalgae cultivation device. 2. The microalgae harvester according to claim 1, wherein the harvesting device comprises: a harvesting tool and a filter screen; The harvesting tool is fixedly installed under the frame; The filter screen, installed on the harvesting tool, is used to filter the microalgae in the algae liquid when moving with the harvesting tool, and enrich the microalgae into a selected area in the microalgae cultivation device . 3. The microalgae harvester according to claim 2, wherein the driving device comprises: a power device and a transmission device; The transmission device is fixedly installed in the middle cavity of the frame, and is connected with the power device fixedly installed above the frame; and transmits the power provided by the power device to a connected to itself set of wheels. 4. The microalgae harvester according to claim 3, wherein the transmission device comprises: a belt and two pulleys; The two pulleys are installed in the middle cavity of the frame, wherein one pulley is connected with the power device, and the other pulley is connected coaxially with a group of wheels; The belt and the two pulleys form a belt transmission mechanism, which drives the wheels to rotate. 5. The microalgae harvester according to claim 4, wherein the transmission device further comprises: a worm wheel and a worm; The worm wheel and the worm are installed in the middle cavity of the frame; the worm is connected with the power device, and the worm wheel is connected with the one pulley to realize power transmission. 6. The microalgae harvester according to any one of claims 2-5, wherein the shape and size of the harvesting tool are determined by the cross-sectional shape of the microalgae cultivation device and the suspension state of the microalgae; specifically include: If the microalgae are suspended and distributed in the algae liquid, the size of the harvesting tool is equal to or slightly smaller than the size of the cross section of the microalgae cultivation device, and the shape is the same as the cross section; If the microalgae floats on the surface of the algae liquid or sinks at the bottom of the algae liquid, the size and shape of the harvesting tool are determined by the height of the distribution area of the microalgae and the cross-sectional shape of the microalgae cultivation device within the height range. 7. The microalgae harvester according to claim 6, characterized in that the harvesting tool has flexible materials on both sides and bottom, which are used to clean the side wall and bottom of the microalgae cultivation device when moving with the harvesting tool. 8. The microalgae harvester according to claim 7, characterized in that, the mesh aperture size of the filter screen ranges from 1 μm to 1000 μm, which is selected according to the type of microalgae and/or the size of the microalgae. Filters with different mesh pore sizes. 9. The microalgae harvester according to any one of claims 1-5, further comprising: The guide part is installed on the front or rear outer wall of the frame, and is used to ensure that the microalgae harvester moves along the track provided on the microalgae cultivation device. 10. A microalgae harvesting system, comprising: a microalgae cultivation device, a microalgae harvester and a microalgae harvesting vehicle; The microalgae cultivation device is used to hold the algae liquid containing microalgae, and a track is arranged on it; The microalgae harvester is used to move along the track provided on the microalgae cultivation device, and filter and collect the microalgae in the algae liquid through the harvesting device provided below it, so as to enrich the microalgae into the microalgae culture within a selected area of the device; The microalgae harvesting vehicle is used for collecting microalgae-enriched algae liquid in a selected area of the microalgae cultivation device. 11. The system according to claim 10, wherein the microalgae harvester comprises: a frame driving device, a harvesting device and at least one set of wheels; The driving device is installed on the frame and is used to provide power to a group of wheels connected to itself; The harvesting device is fixedly installed under the frame, and is used to filter and collect the microalgae in the algae liquid, and enrich the microalgae into a selected area in the microalgae cultivation device; The wheels are fixedly installed under the frame; wherein at least one set of wheels is connected to the driving device and rotates under the power provided by the driving device; the harvesting device is driven by the rotation of the wheels Moving along the track set on the microalgae cultivation device, the microalgae in the algae liquid can be enriched in the selected area of the microalgae cultivation device. 12. The microalgae harvesting system according to claim 11, characterized in that, the harvesting device contained in the microalgae harvester comprises: a harvesting tool and a filter; The harvesting tool is fixedly installed under the frame; The filter screen, installed on the harvesting tool, is used to filter the microalgae in the algae liquid when moving with the harvesting tool, and enrich the microalgae into a selected area in the microalgae cultivation device . 13. The microalgae harvesting system according to claim 12, characterized in that, the drive device included in the microalgae harvester comprises: a power device and a transmission device; The transmission device is fixedly installed in the middle cavity of the frame, and is connected with the power device fixedly installed above the frame; and transmits the power provided by the power device to a connected to itself set of wheels. 14. The system of claim 13, wherein the microalgae harvester further comprises: The guide part is installed on the front or rear outer wall of the frame, and is used to ensure that the microalgae harvester moves along the track provided on the microalgae cultivation device. 15. The system according to claim 12, wherein the shape and size of the harvesting tool are determined by the cross-sectional shape of the microalgae cultivation device and the suspension state of the microalgae; specifically comprising: If the microalgae are suspended and distributed in the algae liquid, the size of the harvesting tool is equal to or slightly smaller than the size of the cross section of the microalgae cultivation device, and the shape is the same as the cross section; If the microalgae floats on the surface of the algae liquid or sinks at the bottom of the algae liquid, the size and shape of the harvesting tool are determined by the height of the distribution area of the microalgae and the cross-sectional shape of the microalgae cultivation device within the height range. 16. The system according to claim 15, characterized in that the harvesting tool installed on the microalgae harvester has flexible materials on both sides and bottom, which are used to clean the side wall of the microalgae cultivation device when moving with the harvesting tool and the underside. 17. The microalgae harvesting system according to claim 12, characterized in that the mesh aperture size of the filter installed on the microalgae harvester ranges from 1 μm to 1000 μm, depending on the type of microalgae and/or Or the size of microalgae selects the filter screen with different mesh apertures. 18. The microalgae harvesting system according to any one of claims 10-17, characterized in that, the microalgae harvesting vehicle includes: a harvesting pump, a vehicle-mounted small settling tank and an ordinary vehicle body; The harvesting pump is used to extract the microalgae-enriched algae liquid in the selected area of the microalgae cultivation device; The vehicle-mounted small settling tank is used to store the microalgae-enriched algae liquid pumped out by the harvesting pump; The common car body is used as the carrier of the harvest pump and the vehicle-mounted small sedimentation tank, so that the harvest pump and the vehicle-mounted small sedimentation tank can move between multiple microalgae cultivation devices. 19. The microalgae harvesting system according to claim 18, further comprising: The filtration and dehydration system is used for filtering and dehydrating the microalgae-enriched liquid transported by the microalgae harvesting vehicle to obtain a dehydrated algae cake. 20. A method for harvesting microalgae, comprising: The microalgae harvester moves along the track set on the microalgae culture device containing the microalgae liquid, and through the harvesting device installed below it, collects the microalgae in the algae liquid by filtration, and enriches the microalgae into the microalgae within selected areas of the culture device; and The microalgae harvesting vehicle collects the microalgae-enriched algae liquid in the selected area of the microalgae cultivation device. 21. The method according to claim 20, wherein the shape and size of the harvesting tool are determined by the cross-sectional shape of the microalgae cultivation device and the suspension state of the microalgae; specifically comprising: If the microalgae are suspended and distributed in the algae liquid, the size of the harvesting tool is equal to or slightly smaller than the size of the cross section of the microalgae cultivation device, and the shape is the same as the cross section; If the microalgae floats on the surface of the algae liquid or sinks at the bottom of the algae liquid, the size and shape of the harvesting tool are determined by the height of the distribution area of the microalgae and the cross-sectional shape of the microalgae cultivation device within the height range. 22. The method of claim 20, further comprising: The microalgae harvester is provided with guide components to ensure its movement along the track provided on the microalgae cultivation device. 23. The method according to claim 22, characterized in that flexible materials are fixedly installed on both sides and bottom of the harvesting tool, and when moving with the harvesting tool, the side walls and bottom of the microalgae cultivation device are cleaned. 24. The method according to claim 23, characterized in that, according to the type of microalgae and/or the size of the microalgae, filter screens with different mesh apertures are selected; The value range of the mesh aperture of the filter screen is 1 μm˜1000 μm. 25. The method according to claim 20, wherein the microalgae harvesting vehicle collects the microalgae-enriched algae liquid in the selected area of the microalgae cultivation device, specifically comprising: The harvesting pump installed on the microalgae harvesting vehicle pumps out the microalgae-enriched liquid in the selected area of the microalgae cultivation device, and stores it in the vehicle-mounted small settling tank installed on the microalgae harvesting vehicle. 26. The method according to claim 25, characterized in that, when there are multiple microalgae cultivation devices, the microalgae harvesting vehicle moves among the multiple microalgae cultivation devices to collect each microalgae The microalgae in the selected area of the culture device are enriched with algae liquid. 27. The method according to any one of claims 20-26, further comprising: The filtration and dehydration system filters and dehydrates the microalgae-enriched liquid transported by the microalgae harvesting vehicle to obtain a dehydrated algae cake.

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