Algae enrichment device and method

Abstract

The algae enrichment device comprises a filter bottle for containing a water sample, and further comprises a filter assembly, and the filter assembly comprises a filter body floating on the surface of the water sample, a liquid discharge channel connected with the filter body and used for discharging supernatant liquid of the water sample, and a single-layer metal filter membrane covering the outer surface of the filter body and used for preventing algae from entering the liquid discharge channel; the filtering assembly further comprises a water suction pump connected with the liquid discharging channel. The method can efficiently enrich the algae in the water sample, effectively improve the algae density, and ensure the non-destructive survival of the algae, thereby improving the representativeness and accuracy of the detection result.

Description

Technical Field

[0001] The present invention relates to the technical field of ecological environment engineering, and in particular to a design of an algae enrichment device integrating gravity sedimentation and filtration. Background Art

[0002] For the sampling detection of algae in water bodies, generally, professional equipment such as microscopes is required to detect smaller-volume samples (generally 0.1 mL). If the algal density of the sample to be tested is too small, large errors will be generated due to sampling detection, and even the results will be incorrect. To improve the representativeness and accuracy of the detection results, when the algal density in the water sample is low, enrichment is required to increase the algal density.

[0003] Most of the existing enrichment methods adopt the natural sedimentation method, that is, after treatment with Lugol's reagent, the sample is placed in a sample cup and allowed to settle statically, and then the supernatant is removed to obtain a concentrated solution. Although this method can be well compatible with different algae, it relies on the gravity sedimentation of algal bodies, which is time-consuming and inefficient, and it is difficult to meet the requirements of high-frequency emergency monitoring during algal blooms. To solve this problem, some technologies adopt the methods of centrifuge centrifugation and membrane filtration to achieve rapid concentration and enrichment.

[0004] However, the defects of the existing technologies are that they cannot meet the two conditions of efficient enrichment and non-destructive retention of live algal bodies at the same time. The natural sedimentation method is not only time-consuming and inefficient, but also the use of Lugol's reagent will cause algal body breakage, resulting in partial loss of algal bodies. Although centrifuge enrichment can efficiently concentrate algal bodies, it is difficult to simply and rapidly enrich different characteristics of algae. For a single algal species, although the appropriate centrifugation speed and time can be determined through experiments to avoid damage to the algal bodies while concentrating them, in actual natural water samples, there are many and uncertain algae species, including diatoms, cyanobacteria, green algae, dinoflagellates, etc., and their morphologies and densities vary significantly. When centrifuging at a low speed, diatoms and dinoflagellates with large densities are effectively concentrated, but cyanobacteria and green algae may not be effectively concentrated; while high-speed centrifugation may cause some algae to be squeezed and damaged; in addition, when some algae exist in a floating state, centrifugation cannot concentrate them. During the enrichment process of membrane filtration, ordinary filter membranes have problems such as low porosity, wide pore size distribution, and multi-layer fiber structure. Generally, vacuum filtration or extrusion of a syringe towards the filter head is required to accelerate the filtration process. During membrane filtration, algal bodies and particles such as sediment will clog the filter membrane, which will reduce the filtration efficiency, and the pressure difference on both sides of the membrane will cause algal bodies to be embedded in the membrane and difficult to elute or damaged, etc. And the wide pore size distribution of the filter membrane results in either choosing an extremely small pore size to prevent algal bodies from passing through the filtration pores, but it is more likely to be clogged; or a large pore size causes some algae to enter the waste liquid and be lost. Summary of the Invention

[0005] In view of the above-mentioned defects of the prior art, the present invention provides an algae enrichment device and method, which can efficiently enrich algal bodies in water samples, effectively increase the algal body density, and ensure the non-destructive survival of algal bodies, thereby improving the representativeness and accuracy of detection results.

[0006] To achieve the above object, the technical solution adopted by the present invention is: An algae enrichment device, comprising a filter bottle for holding a water sample, and further comprising a filtration assembly. The filtration assembly includes a filter body floating on the surface of the water sample, a drainage channel connected to the filter body and used for discharging the supernatant of the water sample, and a single-layer metal filter membrane covering the outer surface of the filter body and used for blocking algal bodies from entering the drainage channel; the filtration assembly further includes a water pump connected to the drainage channel.

[0007] The enrichment principle of this device is as follows: Let the water sample stand and settle in the filter bottle for a few minutes, and then use the filtration assembly to extract the supernatant in the filter bottle. The filter body floats on the surface of the water sample and descends as the liquid level drops. The waste liquid filtered by the filter body is discharged through the drainage channel driven by the water pump. The algal bodies are blocked by the filter body and retained in the solution of the filter bottle. Finally, the water sample enriched with algae remains at the bottom of the filter bottle, realizing the non-destructive and efficient enrichment of algal samples.

[0008] The reason why the enrichment efficiency of this device is higher than that of the gravity sedimentation method is that the density of algal bodies in water is similar to that of water, and their sedimentation speed is relatively slow. Simply relying on gravity sedimentation, it takes a long time (usually 24 - 48 hours) to effectively enrich algal bodies. This device combines the enrichment method of membrane filtration, and can quickly push the water sample through the single-layer metal filter membrane by the external force of the water pump, intercepting the algal bodies on the single-layer metal filter membrane, greatly improving the enrichment speed. First, initially enrich a part of the algal bodies and impurities (such as sediment, organic matter, fibers, microorganisms, etc.) through gravity sedimentation, effectively reducing the particulate matter in contact with and processed by the filter membrane of the filter body, and effectively reducing the risk of filter pore blockage of the filter membrane; then use membrane filtration to efficiently filter the supernatant, quickly reducing the volume of the water sample until the target volume is reached to achieve concentration, and finally obtaining a high-density algal water sample. The overall efficiency of this enrichment method is much higher than that of the gravity sedimentation method.

[0009] The reason why this device can ensure the survival of algal bodies during filtration is that traditional filter membranes are fiber membranes and porous membranes, which are easy to adhere to algal bodies, and the algal bodies are easily damaged and die under the dual action of adhesion and suction. Metal membranes are usually used for surface-enhanced Raman scattering (SERS) detection, designing optical metamaterials, and catalytic reactions. The present invention creatively uses a metal membrane as the filter membrane, and uses its characteristics of high porosity and smooth surface that do not adhere to algal bodies to ensure a high filtration flow rate and no adhesion of algal bodies when filtering the water sample, and will not adsorb or entangle algal bodies to cause damage to the algal bodies.

[0010] It should be noted that the metal used in the single-layer metal filter membrane of this technical solution needs to be corrosion-resistant, acid and alkali-resistant, and have a certain flexibility. The reason for using a single-layer metal filter membrane is that the surface in contact with the algae needs to be smooth to avoid entangling the algae. Multi-layer metal filter membranes are prone to form multi-layer pores, be uneven, and it is difficult to completely wash off the hooked algae. The pore size of the single-layer metal filter membrane is limited according to the specific size of the algae, and different types of algae are concerned in different application scenarios.

[0011] Preferably, an impurity filter pad is provided inside the filter bottle, and there is an algae deposition area between the impurity filter pad and the bottom of the filter bottle.

[0012] During the algae enrichment process, the water sample may contain other impurities (such as suspended particles, sediment, etc.). If these impurities are mixed into the final algae-enriched water sample, it will affect subsequent detection or analysis. The impurity filter pad is installed inside the filter bottle, and the algae deposition area is used for the algae to deposit at the bottom of the filter bottle. When in use, the water sample is poured into the filter bottle. The pores of the impurity filter pad are much larger than the diameter of the algae, which can effectively intercept these larger particle impurities but not intercept the algae, making the water sample more pure after passing through the impurity filter pad. This not only improves the purity of algae enrichment but also reduces interference factors in subsequent treatment steps, making the algae enrichment effect more ideal.

[0013] Preferably, a vibrator is also included.

[0014] The density of algae in water is similar to that of water, and the sedimentation speed is slow. By setting a vibrator outside the filter bottle, a certain mechanical vibration can be applied to the water sample inside the filter bottle. This vibration can disturb the water sample, making the movement of algae particles in the water more intense, thereby accelerating the sedimentation process of algae. Compared with simple gravitational sedimentation, the addition of a vibrator can significantly shorten the time required for algae enrichment and improve the enrichment efficiency.

[0015] During the algae enrichment process, a small part of the impurities may adhere to the single-layer metal filter membrane. Although the single-layer metal filter membrane has the characteristics of high porosity and non-adhesion to algae, its pore size is relatively small and is easily blocked by larger impurity particles. The vibration of the vibrator can generate a small vibration on the single-layer metal filter membrane to help loosen the algae or impurities attached to the surface. The vibrator can also prevent the impurity filter pad from being blocked, thereby maintaining the high-throughput characteristics of the impurity filter pad and ensuring the efficiency of algae enrichment to the bottom of the filter bottle.

[0016] Preferably, the water pump is connected with a touch control device for controlling the water pump; the touch control device includes a touch display screen and a central controller connected to the touch display screen.

[0017] The touch display screen provides an intuitive operation interface for users. Users can control functions such as the start, stop, and flow rate adjustment of the water pump through simple touch operations. This operation method is more intuitive and convenient than traditional mechanical buttons or knobs, reducing the operation complexity. The touch display screen can display the working status of the water pump in real time (such as flow rate, running time, pressure, etc.), enabling users to understand the progress of the enrichment process at any time, so as to better adjust the operation parameters. Through the touch device, users can accurately adjust the flow rate of the water pump. This is very important for the algae enrichment process because different algae enrichment requirements may require different flow rate settings. Precise flow control can ensure that algae are not washed away due to excessive flow rate during the filtration process, nor will the enrichment efficiency be reduced due to too small a flow rate. The central controller can automatically control the operation of the water pump according to the preset program. Through the automated control of the touch device and the central controller, human operation errors are reduced, ensuring that each enrichment process can be carried out according to the preset parameters, improving the enrichment efficiency and the consistency of the results. The introduction of the touch display screen and the central controller makes the operation of the algae enrichment device more intelligent and user-friendly. Even non-professionals can quickly get started, lowering the usage threshold of the device.

[0018] Preferably, the water pump is a peristaltic pump.

[0019] A peristaltic pump is a pump that transports fluids by squeezing a hose. Its working principle determines that it can very precisely control the flow rate of the fluid. In this device, the peristaltic pump can precisely control the discharge speed of the supernatant, thus better regulating the filtration process. This precision can prevent the algal cells from being embedded in the filter pores and damaged due to a large pressure difference across the membrane caused by excessive flow rate, or the filtration efficiency from being reduced due to too small a flow rate. The forward and reverse rotation of the peristaltic pump can effectively remove the enriched algae and impurities during metal membrane filtration, preventing blockage and ensuring the filtration efficiency. Specifically, the peristaltic pump rotates forward to extract the waste liquid and intermittently rotates in reverse to flush away the algae and impurities accumulated near the membrane. This cycle is repeated to prevent blockage while pumping the liquid. The structure of the peristaltic pump is relatively simple compared to ordinary water pumps, mainly consisting of a pump head and a hose. Since the fluid is only transported through the hose, the fluid passage can be easily cleaned and disinfected when replacing the hose. This is very important for the algae enrichment device because different types of water samples may be involved in the algae enrichment process and need to be cleaned regularly to prevent cross-contamination. This design of the peristaltic pump makes the maintenance of the device more convenient and reduces the usage cost.

[0020] Preferably, the material of the filter bottle is high-purity PFA.

[0021] High-purity PFA (perfluoroalkoxy polymer) is a high-performance fluoropolymer with extremely high chemical stability. The surface of the high-purity PFA material is extremely smooth, and its micro-structure has almost no rough points for the algal thalli to adhere to. Algal thalli usually look for areas with minute unevenness or chemical activity on the surface in the water sample for attachment, while the smooth surface of the PFA material makes it difficult for the algal thalli to stay or adsorb on it. The PFA material has an extremely low surface energy, and the interaction force between it and the algal thalli is very weak. Since the algal thalli do not adsorb on the inner wall of the filter bottle, during the enrichment process, the algal thalli can settle more effectively to the bottom of the filter bottle rather than being attached to the inner wall, which makes the concentration of algae finally enriched at the bottom of the filter bottle higher and significantly improves the enrichment efficiency.

[0022] Preferably, the material of the single-layer metal filter membrane is nickel.

[0023] Nickel material can be made into a single-layer metal filter membrane with high porosity through special processing techniques (such as the preparation of nano-porous structures). High porosity means that the filter membrane has more pores per unit area, allowing more water samples to pass through, thereby improving the filtration efficiency. Due to the high porosity of the nickel filter membrane, the water sample can be quickly discharged by a water pump, while the algal thalli are retained on the membrane surface, significantly shortening the time for algae enrichment and improving the enrichment efficiency of the entire device. The pore size of the nickel filter membrane can be precisely controlled through the processing technique and can be customized according to the size of the specific algal thalli. This enables the single-layer metal filter membrane to effectively block the required algal thalli from entering the drainage channel while allowing the water sample to pass through quickly, achieving efficient algae enrichment.

[0024] Nickel is a metal with relatively strong corrosion resistance and can remain stable in a variety of water sample environments and is not easily eroded by the chemical substances in the water sample. This is very important for the long-term use of the algae enrichment device in different water qualities (such as acidic, alkaline or saline water samples). The corrosion resistance of the nickel material makes it not easily damaged during the algae enrichment process, thereby extending the service life of the filter membrane and reducing the maintenance cost of the device.

[0025] The surface of the nickel material is relatively smooth and has strong chemical inertness, and it is not easily chemically adsorbed with the algal thalli. Compared with traditional fiber membranes or porous membranes, the nickel filter membrane can effectively reduce the adhesion of the algal thalli and avoid damage to the algal thalli due to adsorption. Since the nickel filter membrane does not adhere to the algal thalli, the algal thalli will not be adsorbed or entangled on the membrane surface during the filtration process, thus avoiding the rupture or deformation of the algal thalli caused by mechanical force and ensuring the integrity of the algal thalli during the enrichment process.

[0026] An algae enrichment method, in which the water sample is poured into the filter bottle for sedimentation; the upper clear liquid in the filter bottle is filtered by the filtration component; the filtration component includes a filter body floating on the surface of the water sample, a drainage channel connected to the filter body and used to discharge the upper clear liquid of the water sample, and a single-layer metal filter membrane covering the outer surface of the filter body and used to block algae from entering the drainage channel; the filtration component further includes a water pump connected to the drainage channel.

[0027] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. The present invention combines two enrichment methods of gravity sedimentation and membrane filtration. It not only utilizes the natural enrichment effect of gravity sedimentation but also further removes the residual algae in the upper clear liquid through membrane filtration, thus achieving rapid and efficient algae enrichment. By combining gravity sedimentation and membrane filtration, the present invention avoids the drastic operations that may damage the algae in traditional enrichment methods. Through the algae enrichment device of the present invention, the algae can be efficiently enriched to the bottom of the filter bottle, and finally, the enriched algae water sample obtained has a high concentration and good purity. This enables a more accurate reflection of the true situation of the algae in the water sample during detection, avoiding detection errors caused by algae dilution or loss.

[0028] 2. The single-layer metal filter membrane has a high porosity, which can ensure a high filtration flow rate and does not adhere to algae. This means that during the filtration process, the algae will not be adsorbed or entangled on the membrane surface, thus avoiding the problem of decreased filtration speed caused by membrane blockage in traditional filtration methods and ensuring the efficiency of the filtration process. The characteristics of the single-layer metal filter membrane enable the algae to not be physically damaged during the filtration process. Traditional membrane filtration methods may cause algae to rupture or deform due to too small membrane pores or too high filtration pressure, while the metal membrane of the present invention, due to its highly ordered nano-structure, can effectively avoid the adsorption and entanglement of algae, thus ensuring the integrity of the algae. The single-layer array metal membrane 3 is usually used in fields such as surface-enhanced Raman scattering (SERS) detection, design of optical metamaterials, or catalytic reactions. The present invention creatively applies it to algae enrichment, utilizes its high porosity and the characteristic of not adhering to algae, solves the problems existing in traditional enrichment methods, and brings a new breakthrough to the algae enrichment technology. Description of the Drawings

[0029] Figure 1 It is a schematic structural diagram of Embodiment 1.

[0030] Among them: 1. Filter bottle; 2. Filtration component; 21. Filter body; 22. Single-layer metal filter membrane; 23. Drainage channel; 24. Water pump; 3. Impurity filter pad; 4. Vibrator; 5. Touch control display screen. Detailed Embodiments

[0031] In order to make the technical means, creative features, achieved purposes and effects of the invention easily understood, the present invention will be further described below in conjunction with specific illustrations. However, the present invention is not limited to the following implementation cases.

[0032] It should be noted that the structures, proportions, sizes, etc. shown in the drawings of this specification are only used to cooperate with the content disclosed in the specification for those familiar with this technology to understand and read, and are not used to limit the limiting conditions for the implementation of the present invention. Therefore, they do not have any technical substantial significance. Any modification of the structure, change of the proportional relationship or adjustment of the size, without affecting the effects that the present invention can produce and the purposes that can be achieved, should still fall within the scope covered by the technical content disclosed in the present invention.

[0033] Example 1: As Figure 1 shown, an algae enrichment device includes a filter bottle 1 for containing water samples, and further includes a filtering component 2. The filtering component 2 includes a filter body 21 floating on the surface of the water sample, a drainage channel 23 connected to the filter body 21 and used to discharge the supernatant of the water sample, and a single-layer metal filter membrane 22 covering the outer surface of the filter body 21 and used to block algae from entering the drainage channel 23; the filtering component 2 further includes a water pump 24 connected to the drainage channel 23.

[0034] The enrichment principle of this device is as follows: The water sample is allowed to settle in the filter bottle 1, and then the supernatant in the filter bottle 1 is extracted by using the filtering component 2. The filter body 21 floats on the surface of the water sample and descends as the liquid level drops. The filtered solution is driven by the water pump 24 and discharged through the drainage channel 23. The algae are filtered, and finally the water sample enriched with algae is left at the bottom of the filter bottle 1, realizing the enrichment of the sample.

[0035] The reason why the enrichment effect of this device is higher than that of the gravity sedimentation method is that the density of algae in water is similar to that of water, and its sedimentation speed is relatively slow. Relying solely on gravity sedimentation, it takes a long time to enrich the algae to a certain extent. This device combines the enrichment method of membrane filtration, and can quickly push the water sample through the single-layer metal filter membrane 22 by the external force of the water pump 24, intercepting the algae on the single-layer metal filter membrane 22, greatly improving the enrichment speed. First, a part of the algae is preliminarily enriched by gravity sedimentation, so that the algae gather at the bottom of the water sample; then the supernatant is filtered by membrane filtration to reduce the volume of the water sample, enabling the remaining algae to settle to the bottom faster, and finally leaving a high-density algae water sample at the bottom of the filter bottle. The overall efficiency of this enrichment method is much higher than that of the gravity sedimentation method.

[0036] The reason why this device can ensure the survival of algal bodies during filtration is as follows: Traditional filter membranes are fiber membranes and porous membranes, which are prone to adhering to algal bodies. Under the dual action of adhesion and suction, the algal bodies are easily damaged and die. Metal membranes are usually used for surface-enhanced Raman scattering (SERS) detection, designing optical metamaterials, and catalytic reactions. In this invention, a metal membrane is creatively used as a filter membrane. Utilizing its high porosity and non-adhesion to algal bodies, it can ensure a high filtration flow rate and no adhesion to algal bodies when filtering water samples, and will not adsorb or entangle algal bodies to cause damage to them. It should be noted that the metal used for the single-layer metal filter membrane 22 in this technical solution needs to be corrosion-resistant, acid and alkali-resistant, and have a certain flexibility. The reason for using a single-layer metal filter membrane is that the surface in contact with the algal bodies needs to be smooth to avoid hooking the algal bodies. A multi-layer metal filter membrane is likely to cause multi-layer pores, unevenness, and difficulty in completely eluting the hooked algal bodies. The size of the pores of the single-layer metal filter membrane 22 is limited according to the specific size of the algal bodies, and different algal body categories are concerned in different application scenarios.

[0037] An impurity filter pad 3 is provided inside the filter bottle 1, and there is an algal body deposition area between the impurity filter pad 3 and the bottom of the filter bottle 1. During the algae enrichment process, the water sample may contain other impurities (such as suspended particles, sediment, etc.). If these impurities are mixed into the final algae-enriched water sample, it will affect subsequent detection or analysis. The impurity filter pad 3 is installed inside the filter bottle 1, and the algal body deposition area is used for the algal bodies to deposit at the bottom of the filter bottle 1. When in use, the water sample is poured into the filter bottle 1. The pores of the impurity filter pad 3 are much larger than the diameter of the algal bodies, which can effectively intercept these larger particle impurities but will not intercept the algal bodies, making the water sample more pure after passing through the impurity filter pad 3. This not only improves the purity of algae enrichment but also reduces the interference factors in subsequent treatment steps, making the algae enrichment effect more ideal.

[0038] The water pump 24 is connected to a touch control device for controlling the water pump 24; the touch control device includes a touch display screen 5 and a central controller connected to the touch display screen 5. The touch display screen 5 can achieve pump valve control and display, among which basic functions such as controlling the pump speed, running time, sample list selection, start, pause, etc. need to be controlled and can be added or deleted according to requirements. The algae enrichment device needs to set different parameters and methods according to different water samples to achieve reasonable and efficient enrichment results. The touch display screen 5 provides an intuitive operation interface for users. Users can control functions such as the start, stop, and flow rate adjustment of the water pump 24 through simple touch operations. This operation method is more intuitive and convenient than traditional mechanical buttons or knobs, reducing the operation complexity. The touch display screen 5 can display the working status of the water pump in real time (such as flow rate, running time, pressure, etc.), enabling users to understand the progress of the enrichment process at any time, so as to better adjust the operation parameters. Through the touch control device, users can accurately adjust the flow rate of the water pump 24. This is very important for the algae enrichment process because different algae enrichment requirements may require different flow rate settings. Precise flow rate control can ensure that algae are not washed away due to excessive flow rate during the filtration process, nor will the enrichment efficiency be reduced due to too small a flow rate. The central controller can automatically control the operation of the water pump 24 according to a preset program. Through the automated control of the touch control device and the central controller, human operation errors are reduced, ensuring that each enrichment process can be carried out according to the preset parameters, improving the enrichment efficiency and the consistency of the results. The introduction of the touch display screen 5 and the central controller makes the operation of the algae enrichment device more intelligent and user-friendly. Even non-professionals can quickly get started, reducing the usage threshold of the device.

[0039] The water pump 24 is a peristaltic pump. A peristaltic pump is a pump that transports fluids by squeezing a hose. Its working principle determines that it can very precisely control the flow rate of fluids. In this device, the peristaltic pump can precisely control the discharge speed of the supernatant, thus better regulating the filtration process. This precision can avoid the algae being washed away due to excessive flow rate or the filtration efficiency being reduced due to too small a flow rate. The structure of the peristaltic pump is relatively simple compared to ordinary water pumps, mainly consisting of a pump head and a hose. Since the fluid is only transported through the hose, the fluid channel can be easily cleaned and disinfected when replacing the hose. This is very important for the algae enrichment device because different types of water samples may be involved in the algae enrichment process and need to be regularly cleaned to prevent cross-contamination. This design of the peristaltic pump makes the maintenance of the device more convenient and reduces the usage cost.

[0040] The material of the filter bottle 1 is high-purity PFA. High-purity PFA (perfluoroalkoxy polymer) is a high-performance fluoropolymer with extremely high chemical stability. The surface of the high-purity PFA material is extremely smooth, and its micro-structure has almost no rough points for the algal bodies to adhere to. Algal bodies usually look for areas with tiny concavities and convexities or chemical activity on the surface in the water sample for attachment, while the smooth surface of the PFA material makes it difficult for the algal bodies to stay or adsorb on it. The PFA material has an extremely low surface energy, and the interaction force between it and the algal bodies is very weak. Since the algal bodies do not adsorb on the inner wall of the filter bottle 1, during the enrichment process, the algal bodies can settle more effectively to the bottom of the filter bottle rather than being attached to the inner wall, which makes the concentration of algae finally enriched at the bottom of the filter bottle 1 higher and significantly improves the enrichment efficiency.

[0041] The material of the single-layer metal filter membrane 22 is nickel. The nickel material can be made into a single-layer metal filter membrane with a high porosity through special processing techniques (such as the preparation of a nano-porous structure). High porosity means that there are more pores per unit area of the filter membrane, which can allow more water samples to pass through, thus improving the filtration efficiency. Due to the high porosity of the nickel filter membrane, the water sample can be quickly discharged through the water pump 24, while the algal bodies are retained on the membrane surface, significantly shortening the time of algal enrichment and improving the enrichment efficiency of the entire device. The pore size of the nickel filter membrane can be precisely controlled through the processing technique and can be customized according to the size of the specific algal bodies. This enables the single-layer metal filter membrane 22 to effectively block the required algal bodies from entering the drainage channel 23 while allowing the water sample to pass through quickly, achieving efficient algal enrichment. Nickel is a metal with relatively strong corrosion resistance and can remain stable in a variety of water sample environments and is not easily eroded by the chemical substances in the water sample. This is very important for the long-term use of the algal enrichment device in different water qualities (such as acidic, alkaline or saline water samples). The corrosion resistance of the nickel material makes it not easily damaged during the algal enrichment process, thus extending the service life of the filter membrane and reducing the maintenance cost of the device. The surface of the nickel material is relatively smooth and has strong chemical inertness, and it is not easy to chemically adsorb with the algal bodies. Compared with traditional fiber membranes or porous membranes, the nickel filter membrane can effectively reduce the adhesion of algal bodies and avoid damage to the algal bodies due to adsorption. Since the nickel filter membrane does not adhere to the algal bodies, the algal bodies will not be adsorbed or entangled on the membrane surface during the filtration process, thus avoiding the rupture or deformation of the algal bodies caused by mechanical force and ensuring the integrity of the algal bodies during the enrichment process.

[0042] Example 2: An algae enrichment method, in which the water sample is poured into the filter bottle 1 for sedimentation; the upper clear liquid in the filter bottle 1 is filtered by the filtering component 2; the filtering component 2 includes a filter body 21 floating on the surface of the water sample, a drain channel 23 connected to the filter body 21 and used to discharge the upper clear liquid of the water sample, and a single-layer metal filter membrane 22 covering the outer surface of the filter body 21 and used to block the algae from entering the drain channel 23; the filtering component 2 further includes a water pump 24 connected to the drain channel 23.

[0043] The theoretical basis and experimental research verification of the present invention are as follows: Detection of water turbidity and particle size distribution. Through a turbidimeter and a flow cytometry algae analyzer, the particle size distribution of particulate matter in different water samples such as common rivers and lakes can be established, as well as the proportion w% of impurity particles (w% is the ratio of impurity particles remaining after removing planktonic microorganisms to the total particulate matter).

[0044] The sedimentation of impurity particulate matter refers to the Stokes sedimentation formula , (Note: Vsed is the particle sedimentation velocity, k is the shape factor, g is the acceleration due to gravity, r is the equivalent radius of the particle, d1 is the particle specific gravity, d2 is the water specific gravity, μ is the water viscosity). It is mainly applicable to non-living particles, that is, "impurities" include sediment, microplastics, organic matter, etc. According to the formula, the sedimentation time of different impurities can be simulated, but the theoretical calculation results need to be further corrected by combining with the actual water sample sedimentation experiment. Since planktonic algae, fungal microorganisms and zooplankton can swim autonomously, they are not applicable to the relevant theories and simulations of natural sedimentation.

[0045] If the algal cells come into contact with the filter holes of the filter membrane, the force analysis of them refers to the Poiseuille's law in fluid mechanics: , (Note: Q is the average flow rate of a single filter hole, ∆p is the pressure difference across the filter hole, r is the radius of the filter hole, L is the thickness of the filter hole, d1 is the particle specific gravity, d2 is the water specific gravity, μ is the water viscosity), and the force on the algal cells can be calculated from the pressure difference ∆p across the filter hole.

[0046] Algae include rough classifications of more than a dozen phyla such as Cyanophyta, Chlorophyta, Euglenophyta, Xanthophyta, Cryptophyta, Chrysophyta, Bacillariophyta, Pyrrophyta, etc., and there are nearly 40,000 fine classifications. Some of these algae have relatively fragile cell membranes and are easily damaged by force, some have a siliceous cell shell and are not easily broken, some are wrapped in a transparent gel outside the cell and are not easily damaged, and some exist in the form of aggregates and are not easily damaged by the filter holes of the filter membrane. Therefore, for different types of algae, reasonable experimental methods need to be established according to their characteristics to ensure high efficiency, no damage or a low breakage rate.

[0047] Based on the above four points, it is possible to guide the construction of reasonable experimental methods corresponding to different impurity contents and different algal species, which require a large number of verification experiments and theoretical correction coefficients, etc. The ultimate goal is to achieve rapid and non-destructive enrichment: 1) Try to make the liquid level drop speed V ≤ the sedimentation speed V_sink of impurity particles. Even, it is possible to sediment for a few minutes first and then start the peristaltic pump to pump the filtrate, so as to ensure that the filter pores of the filter membrane do not contact or rarely contact impurity particles, resulting in fewer effective filter pores and an increase in the flow rate Q of a single filter pore. As a result, ∆p, the pressure difference across the filter pore, increases, and the risk of algal cell damage due to force increases; 2) For different algae, within the acceptable range of their breakage rate, increase the flow rate Q of a single filter pore and shorten the enrichment time.

[0048] The flow cytometry-based algal analyzer is a high-precision device for classifying and quantitatively detecting algae based on the image method. It can directly detect live algal water samples on the machine, with a detection time of about 10 minutes, which can meet the needs of batch sample detection and multiple high-frequency detections per day.

[0049] When detecting algae, it is recommended to have between 500 and 1500 algal cells detected each time to ensure good representativeness of the detection. If the concentration of a single sample is too low and the number of algal cells detected is significantly less than 500, it is difficult to ensure the accuracy and reliability of the detection results.

[0050] In natural water samples, there are not only many "impurities", but also large differences in the particle size, morphology, and density of algae, which makes it a pain point for the efficient enrichment of live algae. When the algal cell number density in the water sample is low (10 4 ~10 6 cells / L), enrichment is required to increase the algal density to be greater than 10 7 cells / L so that the flow cytometry-based algal analyzer can detect more than 500 algal cells to improve the detection reliability. Specific detection steps: 1) Collect water samples and pre-detect them on the flow cytometry-based algal analyzer to select water samples with low algal concentration; 2) Determine the enrichment multiples (10 - 100 times) of different low-concentration algal samples, and use this algal enrichment device to enrich different samples and set the corresponding parameters; 3) Detect the enriched and volume-fixed water samples on the flow cytometry-based algal analyzer. Divide the sample detection result by the enrichment multiple to obtain the true result of the sample, and finally output an algal detection report.

[0051] Example 3: The difference from Example 1 is the anti-blocking design of the algal enrichment device. In Example 1, the forward and reverse functions of the peristaltic pump were used for anti-blocking. In this example, a vibrator 4 is used as this functional component.

[0052] The device also includes a vibrator 4 provided at the bottom of the filter bottle 1 and in contact with the filter bottle 1. The density of algae in water is similar to that of water, and the sedimentation rate is slow. By setting the vibrator 4 outside the filter bottle 1, a certain mechanical vibration can be applied to the water sample in the filter bottle 1. This vibration can disturb the water sample, make the movement of algal particles in the water more intense, and thus accelerate the sedimentation process of algae. Compared with simple gravitational sedimentation, the addition of the vibrator 4 can significantly shorten the time required for algae enrichment and improve the enrichment efficiency.

[0053] During the algae enrichment process, a small part of the impurities may adhere to the single-layer metal filter membrane 22. Although the single-layer metal filter membrane 22 has the characteristics of high porosity and non-adhesion to algal bodies, its pore size is relatively small and is easily blocked by larger impurity particles. The vibration of the vibrator 4 can generate a slight vibration on the single-layer metal filter membrane 22 to help loosen the algal bodies or impurities attached to the surface. The vibrator 4 can also prevent the impurity filter pad 3 from being blocked, thereby maintaining the high-throughput characteristics of the impurity filter pad 3 and ensuring the efficiency of algae enrichment at the bottom of the filter bottle 1.

[0054] Example 4: The difference from Example 3 is the installation position of the vibrator. In this example, such an operation method is more suitable for algae with stronger stress. The vibrator is connected to the filter body 21. It is not installed at the bottom of the filter bottle 1 to bring vibration to the filter bottle 1. Instead, it is installed externally to provide vibration to the filter body 21. Such a spatial layout makes the water sample in the filter bottle 1, especially the water sample in the middle and lower parts of the filter bottle 1, remain quiet, avoiding the microorganisms from swimming away due to vibration stimulation. Providing vibration only to the filter body 21 can maintain the stability of the microorganisms on the one hand and provide an anti-blocking design on the other hand.

Claims

1. An algae enrichment device, a filter bottle (1) for containing water samples, characterized in that, It further includes a filtering component (2), and the filtering component (2) includes a filter body (21) floating on the surface of the water sample, a drain channel (23) connected to the filter body (21) and used for discharging the supernatant of the water sample, and a single-layer metal filter membrane (22) covering the outer surface of the filter body (21) and used for blocking algae from entering the drain channel (23); the filtering component (2) further includes a water pump (24) connected to the drain channel (23).

2. The algae enrichment device according to claim 1, characterized in that, An impurity filtering pad (3) is arranged in the filter bottle (1), and there is an algae deposition area between the impurity filtering pad (3) and the bottom of the filter bottle (1).

3. The algae enrichment device according to claim 2, wherein It further includes a vibrator (4).

4. The algal enrichment device according to claim 3, wherein The vibrator (4) is connected to the filter body (21) to provide vibration to the filter body (21).

5. The algae enrichment device according to claim 1, characterized in that, The water pump (24) is connected to a touch control device for controlling the water pump (24); the touch control device includes a touch display screen (5) and a central controller connected to the touch display screen (5).

6. The algae enrichment device according to claim 1, characterized in that, The water pump (24) is a peristaltic pump.

7. The algae enrichment device according to claim 1, characterized in that, The filter bottle (1) is made of high-purity PFA.

8. The algae enrichment device according to any one of claims 1-7, characterized in that, The single-layer metal filter membrane (22) is made of nickel.

9. An algal enrichment method applied to the algal enrichment device described in claim 1, characterized in that, Pour the water sample into the filter bottle (1) for sedimentation; use the filtering component (2) to filter the supernatant in the filter bottle (1); the filtering component (2) includes a filter body (21) floating on the surface of the water sample, a drain channel (23) connected to the filter body (21) and used for discharging the supernatant of the water sample, and a single-layer metal filter membrane (22) covering the outer surface of the filter body (21) and used for blocking algae from entering the drain channel (23); the filtering component (2) further includes a water pump (24) connected to the drain channel (23).

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