46results about How to "High algae removal efficiency" patented technology

The invention belongs to the technical field of environmental protection, and particularly relates to a method and a device for stream guidance and enrichment of blue-green algae in a large water area. With the adoption of the method and the device for the stream guidance and the enrichment of the blue-green algae in the large water area, a certain area which is in shore, and in which the guiding wind is in the downwind direction in the large water area is selected as a blue-green algae stream guidance and enrichment area; a blue-green algae stream guidance and enrichment device is established by utilizing an arched soft algae blocking enclosure and a stream guiding door of which the two sides are in shore; large-scale blue-green algae from outside is guided and gathered to the two sides of the shore by utilizing the arched soft algae blocking enclosure; and the blue-green algae is guided into the enrichment area by utilizing timely opening and closing of the stream guidance door, or the enriched blue-green algae is prevented from blowing and escaping with wind; wind waves in the enrichment area can be reduced by the blue-green algae stream guidance enrichment device, so that the blue-green algae in the enrichment area can always float onto the water surface, and is conveniently to be absorbed and cleared continuously; and in addition, a blue-green algae stream guiding enrichment trap and an efficient algae absorbing area are constructed at one side close to the bottom shore in the blue-green algae stream guidance and enrichment area by utilizing vantage ground, so that the blue-green algae in the enrichment area is further enriched for second time to the area, and is conveniently efficiently absorbed and cleared.

The present invention relates to water treating engineering, and is especially one kind of algae scavenger for water. It is powder finer than 100 mesh and water soluble. After spread into water, it forms floc attached to the surface of various kinds of algae, so that algae deposits to form soft layer in the bottom of water and lacks of photosynthesis to die and the water become clear. The present invention has the beneficial effects of high algae eliminating effect, high safety and reliability, and being suitable for killing algae in lake, river, pond, fish farm and reservoir.

The invention relates to a low-cost, environmental-protection and high-efficiency alga removal combination material. The high-efficiency alga removal combination material capable of rapidly eliminating algae in water and continuously reducing the alga bloom risk of water is disclosed against abundant growth of alga bloom in water reservoirs, lakes, drinking water sources or scenic water. The high-efficiency alga removal combination material comprises a natural mineral modified material and a removal assistant. The natural mineral modified material mainly comprises zeolite, active carbon, mica powder, kaolin or diatomite and other macro-porous mineral matter powders as raw materials, and can adsorb and co-precipitate alga particles and phosphates through acid modification and function group fixing. The modified material can be added to eutrophic water in an in situ manner, and can also be used in drinking water factories. When in situ addition is carried out, the natural mineral modified material is only added if the density of algae in water, and the removal assistant is added if the density of the algae is high in order to improve the effect. The alga removal material does not use toxic substances in the modification process, can efficiently remove algae in the water, and also can remove nitrogen and phosphorus, reduce release of intracellular toxic substances and reduce the alga bloom risk. The natural mineral modified material is especially suitable for alga control of the drinking water sources, the lakes and urban landscape waters, or is used in stringent control or risk prevention of the alga bloom.

The invention discloses a high-efficiency combined purification system for algae-containing wastewater treatment, which comprises a purification container. The system is characterized in that the purification container is sequentially composed of a filter chamber (1), a plasma reaction chamber (2), a flocculating chamber (3) and a water collection chamber (4) from bottom to top, wherein a filter screen is arranged between the filter chamber (1) and the plasma reaction chamber (2); a screen layer is arranged between the plasma reaction chamber and flocculating chamber; the purification container is provided with a water inlet at the filter chamber, and also provided with a water outlet at the water collection chamber. By adopting the integrated combination technique, the system has the advantages of small occupied area, high algae removal efficiency, low reagent consumption and favorable quality of effluent water. By adopting the plasma discharge for oxidization and algae removal, the system greatly lowers the emission of malodorous gas, and reduces the pollution of the malodorous gas to the atmospheric environment. The system has high algae removal rate and favorable removal effect for SS (suspended sediment) and CODcr (chemical oxygen demand).

The invention relates to an algae setting and purifying platform, which is characterized by setting a floating platform, which has a collection area, a reaction area, a concentration area and an isolation area in turn from the front end to the back end, wherein, manual operation areas are respectively arranged on two sides of the reaction area, the concentration area and the isolation area; the floating platform is arranged on two side edges of watertight isolating materials; an upper edge of the two side edges is provided with a floating body of air cell type; two side edges of the collection area are in the shape of a speaker and are toward a front opening of the platform; a hollow bottom is arranged between the two side edges of the collection area; bottoms of the reaction area, the concentration area and the isolation area between the two side edges form a sieve layer. The algae setting and purifying platform can carry out urgent isolation and remove the burst cyanobacteria in water of a large area with a high-efficiency, thus decreasing the environment danger due to the burst of the cyanobacteria and avoiding secondary pollution.

The invention provides an intelligent ultrasonic algae removing device and an algae removing method thereof. The device comprises a shell, a power supply system, a wireless signal transceiving system, a control system, a positioning system, a realtime algae detector, an ultrasonic system, a mechanical power propulsion system, and a floating carrier, and may comprises a water aerator. The power supply system provides continuous and stable electricity to the whole device. The moving route of the algae removing device can be set artificially, furthermore, the moving route can be intelligently and automatically determined according to the detection results of the realtime algae detector; at the same time, through the wireless signal transceiving system, the water quality detection data can be read at any time, and the moving route of the algae removing device can be modified artificially. The provided intelligent ultrasonic algae removing device can read the water quality data in a long distance, has the intelligent positioning and automatic moving functions, has a wide application range, is capable of saving the energy and supplying oxygen to water, greatly improves the algae removing efficiency, and effectively improves the water quality.

The invention relates to the technical field of algicide preparation, in particular to a preparation method of a composite algicide. The preparation method comprises steps as follows: interlayer spacing of montmorillonite is widened firstly, the montmorillonite is soaked with citric acid, cobalt-iron ions are complexed with citric acid, magnetic cobalt ferrite is generated after calcination, hydroxyl free radicals, hydrogen peroxide and ozone produced through a photochemical reaction are promoted to effectively kill algae under the photomagnetic synergistic effect, then snailase rich in different enzymes is supported on a crude algicide product and adopted to damage slime outside the algae, the algae are enabled to be exposed from slime outside the algae, the exposed algae are contacted with copper ions, and the copper ions are adsorbed to algal cell walls, penetrate through the cell walls and remains on cell membranes to inhibit activity of enzymes in the cell membranes and result in algal death finally, so that the purpose of algae removal is achieved. The metal copper ions are chelated on the surface of a magnetic green body, the release speed is reduced, so that the long-time algae removal effect can be achieved, and the preparation method has broad application prospect.

The invention relates to a method for removing algae by applying micro-bubble air flotation of a multiphase flow pump. The method comprises the following step of releasing air dissolved water below a water body containing an algal layer, wherein the air dissolved water is formed in such a way that air and natural water simultaneously enter the multiphase flow pump under the action of negative pressure, dispersed air is cut many times by using a multistage impeller rotating at high speed in the multiphase flow pump, the air is instantly dissolved into the natural water in a highly dispersed state in a high pressure environment in the multiphase flow pump and rapidly saturated, and then is stabilized and contacted by an air dissolved tank for 50seconds-1hour, and the air dissolved water contains a great number of micro air bubbles with the diameter of small than 30mum, and the air dissolved water is released by decompressing to a position 0.3-1.2m away from the downside of the water body containing the algal layer. The method has the advantages of ideal air flotation effect achieved without adding a coagulant, no secondary pollution, no limitation of minimum water treatment quantity, simple process equipment, low device energy consumption and high system operation stability.

The invention discloses an algaecide, a preparation method thereof and an algae removing method. The algaecide is prepared from the following raw materials of red earth and a flocculating agent which are (1.2 to 10) to 1 in mass ratio. In the algaecide disclosed by the invention, the flocculating agent has a modification function on the red earth, so that the problem of worse and instable sedimentation caused by single use of the flocculating agent is avoided, and the algae removing efficiency is increased.

The invention provides a ship-borne type algae-water separating device. The ship-borne type algae-water separating device comprises a ship body, a blue-green algae enriching and absorbing unit arranged on the ship body, a medicine dissolving unit, a dissolved gas generating unit, a gas-floating algae-water separating unit, an algae-slag dehydrating unit, a power generator unit and an electrical control unit. According to the ship-borne type algae-water separating device provided by the invention, the blue-algae enriching and absorbing unit, the medicine dissolving unit, the dissolved gas generating unit, the gas-floating algae-water separating unit and the algae-slag dehydrating unit are arranged on the ship body, so that the whole process of blue-green algae catching, algae-water separating and algae-slag dehydrating can be completed on the ship body, and therefore, algae removal efficiency is improved; and moreover, the ship body can be put into a blue-green algae water bloom regionto perform blue-green algae governing work at any time, so that water body purifying cost is reduced, and adaptability to different areas is improved.

The invention relates to a method for removing blue-green algae by using microbubble hydrodynamic cavitation enhanced coagulation. The method comprises the following steps: (1) selecting a universal microbubble hydrodynamic cavitation generation device; (2) putting algae liquid into a water tank of the microbubble hydrodynamic cavitation generation device, starting a water pump to produce a hydrodynamic cavitation effect, breaking cell walls through a mechanical effect and a heating effect based on hydrodynamic cavitation, killing fronds, and degrading intracellular and extracellular secreta through superstrong oxidization, thus realizing the purification of water; (3) after hydrodynamic cavitation pretreatment, carrying out coagulation so as to achieve a hydrodynamic cavitation enhanced coagulation effect. The invention discloses the method for removing algae by using a microbubble hydrodynamic cavitation technology for the first time. Compared with other algae removal methods such as a chemical agent method, the method is relatively high-efficient and clean; according to the method, the hydrodynamic cavitation technology and coagulation sedimentation are combined so as to improve algae removal efficiency and reduce the dosage of a coagulant.

The invention discloses a double-boat type water bloom removal device. The double-boat type water bloom removal device is composed of double boats, aerating devices, a residue scraping device and a residue collection device. The aerating devices are mounted between bows of the double boats. The residue scraping device is mounted on the rear portions of the double boats. The residue collection device is fixed to sterns of the double boats. An air flotation turbo is adopted for each aerating device. A rotary chain device with a nylon screen is adopted for the residue scraping device. A screw conveying and squeezing integrated machine is adopted for the residue collection device. The double-boat type water bloom removal device is simple in structure, easy and convenient to operate, capable of saving energy, low in cost, high in algae removal efficiency, free of manual cleaning up and salvaging, free of secondary pollution and suitable for removal of algae in various water bodies such as rivers, lakes and river ways.

The invention discloses a magnetic high-efficiency algaecide and a preparation method and application thereof. The preparation method comprises mixing of nano-ferroferric oxide and allelochemicals, wherein the allelochemicals comprise p-hydroxybenzoic acid and / or coumarin. The problems that when nano-materials are used to remove algae, algae cells may desorb under the conditions of wind power andwater conservancy to cause large re-emerge of the algae because the nano-materials are often reversible in adsorption can be solved.

The invention relates to an algae-containing wastewater high-efficiency combined purification method which is characterized by comprising the following steps: (1) filtering the algae-containing wastewater through a filter chamber to remove most suspended substances and partial algae; (2) sending the filtered water body into a plasma reaction chamber, introducing air into the plasma reaction chamber, and carrying out oxidation algae removal on the water body by using a needle-plate reactor in the plasma reaction chamber; (3) sending the water body subjected to oxidation algae removal into a flocculating chamber, and flocculating to form a separable floccule, wherein the floccule is combined with bubbles in the water body to form a floatation body with smaller specific gravity than water, and the floatation body floats to the water surface to condense into scum; and removing the scum to obtain the purified water body. The method has the advantages of high algae removal efficiency, low reagent consumption and favorable effluent water quality. By adopting the plasma discharge for oxidization and algae removal, the method greatly lowers the emission of malodorous gas, and reduces the pollution of the malodorous gas to the atmospheric environment. The system has high algae removal rate and favorable removal effect for SS (suspended sediment) and CODcr (chemical oxygen demand).

The invention belongs to the technical field of algae removal and particularly relates to a preparation method of an environment-friendly algicide. The preparation method comprises the following steps: firstly, treating towel gourd vegetable sponge with hydrogen peroxide to reduce the content of crude fibers inside the towel gourd vegetable sponge; secondly, mixing the treated towel gourd vegetable sponge with acrylic acid, polyglutamic acid, N,N-methylene bisacrylamide and the like, and using potassium peroxodisulfate as an initiator to obtain towel gourd vegetable sponge-supported degradable super absorbent resin; thirdly, extracting algae removing enzyme inside neocaridina denticulate and algae removing beneficial substances in fructus xanthii and radix stemonae; mixing a carrier with extracts, and adsorbing beneficial substances in the extracts; and meanwhile, adding urea for mixing to obtain the environment-friendly algicide. The algicide prepared by the preparation method disclosed by the invention has the characteristics of stability, high removal efficiency and environment friendliness; after the environment-friendly algicide is put into a water body and is used for 40 to 60 minutes, harmful algae in the water body can be settled to the water bottom, and the algae removal rate reaches 96.2 percent or above; and in addition, after the algicide is used, secondary pollution to the water body is avoided.

The invention discloses a rapid underwater algae removal mechanical device. The mechanical device comprises a duckweed removal device body A and an algae removal device body B, an opening is formed inthe center of the bottom of the duckweed removal device body A, the duckweed removal device body A sleeves the algae removal device body B through threads, the duckweed removing device body A comprises a duckweed removal outer barrel (17), a top cover (15) covers a top opening of the duckweed removal outer barrel (17) in a sealed mode, a cylindrical check ring (16) with the depth smaller than thedepth of the duckweed removal outer barrel (17) is fixedly arranged on the inner bottom surface of the top cover (15), blades (14) are arranged in the cylindrical check ring (16), the algae removal device body B comprises an algae removal outer barrel (7), a coarse filter screen (3) is arranged at a water inlet in the side wall of the top edge of the algae removal outer barrel (7), an algae removal device top cover (2) covers a top opening of the algae removal outer barrel (7) in a sealed mode, and a filter barrel (4) of a stainless steel filter screen is concentrically arranged in the algaeremoval outer barrel (7). The mechanical device has the advantages that the algae removal and duckweed removal functions can be achieved, the use is simple, the algae removal efficiency can be improved, the energy source for extracting algae liquid can be saved, and the automatic cleaning function can be achieved.

The invention relates to a flotation device and method for treating cyanobacterial bloom in a eutrophicated water body. The device comprises a ship hull which operates on the water surface in a flotation-type working mode, wherein the flotation type comprises floatation and travel; the front part of the ship hull is provided with an infrared obstacle evasion device for the ship hull to evade obstacles on the water surface; the back part of the ship hull is provided with an aeration device which is positioned underwater and used for supplying oxygen to the water body; the peripheral side of the front part of the ship hull is also provided with a plurality of ultrasonic transducers for emitting ultrasonic to remove and inhibit algal growth; the back part of the ship hull is provided with solar panels which are oblique relative to the horizontal surface; the solar panels are used for transmitting the converted electric power to a power supply system on the ship hull, so that the electric power can be used by the complete device; and the tail of the ship hull is provided with a propeller for driving the ship hull to travel. The device can make a turn when meeting an obstacle; the aeration device is utilized to enhance the self-purification capacity of the water body, thereby enhancing the cyanobacterial bloom treatment efficiency; and the device has the advantages of low manufacturing cost and low operating cost.

The invention discloses a preparing method of an algicide base material, algicide and a preparing method and application of the algicide. The preparing method of the algicide base material includes the steps that 1, sweet wormwood herb and calcium chloride are mixed to prepare a mixture M1, and the mixture M1 and gaseous phase white carbon black are partitioned through filter paper to prepare a material to be filtered; 2, starch, hydrochloric acid and water are mixed to prepare a starch solution; the starch solution prepared in the step 2 and the material to be filtered are mixed and filtered to prepare the algicide base material. The preparing method of the algicide includes the steps that 1, the algicide base material prepared through the preparing method is extracted with ethyl acetate and then crystallized to prepare a crystal substance; 2, starch, hydrochloric acid and water are mixed to prepare a starch solution; 3, the crystal substance prepared in the step 1 and the starch solution prepared in the step 2 are mixed to prepare the algicide. By means of the design, the algicide has the advantages of being free of pollution, wide in material source, low in cost, convenient to use, high in algae removal efficiency and high in performance cost ratio.

The invention discloses a high-efficiency combined purification system for algae-containing wastewater treatment, which comprises a purification container. The system is characterized in that the purification container is sequentially composed of a filter chamber (1), a plasma reaction chamber (2), a flocculating chamber (3) and a water collection chamber (4) from bottom to top, wherein a filter screen is arranged between the filter chamber (1) and the plasma reaction chamber (2); a screen layer is arranged between the plasma reaction chamber and flocculating chamber; the purification container is provided with a water inlet at the filter chamber, and also provided with a water outlet at the water collection chamber. By adopting the integrated combination technique, the system has the advantages of small occupied area, high algae removal efficiency, low reagent consumption and favorable quality of effluent water. By adopting the plasma discharge for oxidization and algae removal, the system greatly lowers the emission of malodorous gas, and reduces the pollution of the malodorous gas to the atmospheric environment. The system has high algae removal rate and favorable removal effect for SS (suspended sediment) and CODcr (chemical oxygen demand).

The invention discloses a method for efficiently removing algae from water bodies utilizing ultrasonic-treated carbon nanotubes. The method comprises the steps of: firstly adding carbon nanotubes to tap water to prepare carbon tube aqueous solution with certain mass concentration; secondly adjusting the pH value of the carbon tube aqueous solution to 5.0-9.0 with NaOH solution or HCl solution; then placing a container holding the carbon tube aqueous solution with pH value adjusted in an ultrasonic device; and finally adding the ultrasonic-treated carbon tube suspension to water bodies containing algae, quickly stirring and shaking uniformly, and then standing and settling the mixed liquid of carbon nanotubes and algae to efficiently remove algae from the water bodies. According to the invention, the used carbon nanotubes are a novel carbon material, which has strong agglomeration and settling capability to algae; and as compared with the traditional carbon material such as activated carbon, the carbon nanotubes have higher removal rate and higher removal speed of algae, and are simple in operation and wide in application conditions.

The invention discloses a mobile ultrasonic algae removal device, which comprises an overwater moving carrier and an ultrasonic algae removal mechanism, wherein the overwater moving carrier is provided with a base, and a through cavity is formed in the center of the base; and the ultrasonic algae removal mechanism is fixed in the through cavity of the base and comprises a supporting component fixed to the base and an ultrasonic algae removal component fixed to the supporting component in the vertical direction, the ultrasonic algae removal component comprises a plurality of first ultrasonic algae removal parts and a plurality of second ultrasonic algae removal parts, the first ultrasonic algae removal parts and the second ultrasonic algae removal parts are arranged on the supporting component at intervals in a staggered mode, and the frequencies of the ultrasonic waves emitted by the two are different. The ultrasonic algae removal mechanism is arranged on the overwater moving carrier, so that the device can travel to an area where algal blooms occur in time, ultrasonic algae removal treatment is performed in time, and the device is convenient, rapid and high in algae removal effect rate.

The invention relates to a composite algae removal method for graphene oxide. The composite algae removal method comprises the following steps: (1) adding a CuSO4 or CdCl2 algae removal into a solution containing blue algae, and controlling the Cu<2+> concentration in the solution to be 0.05-0.10mg / L or controlling the Cd<2+> concentration in the solution to be 0.4-0.7mg / L; (2) adding graphene oxide into the solution, controlling the concentration of the graphene oxide to be 0.8-10mg / L, and separating floc in the solution after stirring, thereby completing algae removal. Compared with the prior art, the graphene oxide is added and can be adsorbed on the surfaces of algae cells, so that heavy metals in water can be enriched by a nano material when a little nano graphene oxide and the heavy metal ions co-exist in water, and the algae removal efficiency of the heavy metals is greatly improved.

The invention relates to an algae setting material, which comprises 5 to 70 percent of natural fiber material and 30 to 95 percent of natural high polymer material, wherein, the natural fiber material is selected from plant fiber and / or animal fiber, and the natural high polymer material is selected from crab derivatives and / or shrimp derivatives and plant viscous juice with a proportion no less than 5 percent. The algae setting material is the natural substance without any harm to human bodies, livestock, environment as well as aquatic animals and plants, and has coagulation, adsorption, tangling and enmeshing function for the algae. When the use amount of the algae material is 0.1 to 10mg / L, the removal efficiency of the algae is over 95 percent. The obtained algae setting body of the flocculation has strong holding power, good performance of floating and drainability, little algae mug and convenient post-process, so the invention is applicable to urgent treatment of burst red tide in ease water and water bloom in fresh water.

The invention relates to an algae-collecting algae-blocking and algae-guiding surrounding separation system, and belongs to the technical field of ecological restoration. The algae-collecting and algae-blocking and algae-guiding surrounding separation system comprises a algae-blocking embankment, a flow-pushing device, a gate and an artificial wetland; the algae-blocking embankment is arranged inthe water body, the two ends of the algae-blocking embankment extend to an embankment, the top of the alga-blocking embankment is provided with an inwards-concave algae guiding ditch, and the height of the algae-blocking embankment is gradually reduced from the middle to the two ends, the height of the groove bottom of the algae guiding ditch is gradually reduced from the middle to the two ends, and the lowest point of the top of the algae-blocking embankment is higher than the water surface; a plurality of flow pushing devices are arranged in the algae guiding ditch at intervals; the two endsof the alga guiding ditch are respectively provided with a gate; and the artificial wetland is positioned in an area surrounded by the algae-blocking embankment and the embankment. According to the surrounding separation system, the algae removal and ecological restoration are combined, no negative influence is caused to the environment, the surrounding separation system can be applied to a largewater area, is relatively high in algae removal efficiency, algae substances in the water body do not need to be fished manually, the labor intensity of workers is reduced, and meanwhile, the algae substances in the water body can be salvaged by replacing other energy consumption equipment.

A method for enhancing algae coagulation using nitrogen-doped titanium dioxide and degrading algae-containing sediment in visible light simultaneously, comprising: (1) adding an algae-removing coagulant to the algae-containing water for stirring to complete coagulation, the algae-removing coagulant consisting of 50-400 parts by weight of N-TiO2 powder and 7.5 parts by weight of polyaluminum ferric chloride; (2) removing the algae in the supernatant after static sedimentation is conducted and algae-containing floc subsides to bottom; and (3) discarding the supernatant, keeping the algae-containing sediment at the bottom, and placing the algae-containing sediment in the visible light for irradiating and stirring, and after a certain time, degrading the algae and algal toxins. The method can reduce the usage amount of coagulant to enhance the coagulation effect and can degrade the algae and microcystic toxins in the sediment, and is applicable to treat water source of high algae density and sediment of high algal density.

The invention discloses a method for efficiently removing algae from water bodies utilizing ultrasonic-treated carbon nanotubes. The method comprises the steps of: firstly adding carbon nanotubes to tap water to prepare carbon tube aqueous solution with certain mass concentration; secondly adjusting the pH value of the carbon tube aqueous solution to 5.0-9.0 with NaOH solution or HCl solution; then placing a container holding the carbon tube aqueous solution with pH value adjusted in an ultrasonic device; and finally adding the ultrasonic-treated carbon tube suspension to water bodies containing algae, quickly stirring and shaking uniformly, and then standing and settling the mixed liquid of carbon nanotubes and algae to efficiently remove algae from the water bodies. According to the invention, the used carbon nanotubes are a novel carbon material, which has strong agglomeration and settling capability to algae; and as compared with the traditional carbon material such as activated carbon, the carbon nanotubes have higher removal rate and higher removal speed of algae, and are simple in operation and wide in application conditions.

The invention relates to an algae-collecting algae-blocking and algae-guiding surrounding separation system, and belongs to the technical field of ecological restoration. The algae-collecting and algae-blocking and algae-guiding surrounding separation system comprises a algae-blocking embankment, a flow-pushing device, a gate and an artificial wetland; the algae-blocking embankment is arranged inthe water body, the two ends of the algae-blocking embankment extend to an embankment, the top of the alga-blocking embankment is provided with an inwards-concave algae guiding ditch, and the height of the algae-blocking embankment is gradually reduced from the middle to the two ends, the height of the groove bottom of the algae guiding ditch is gradually reduced from the middle to the two ends, and the lowest point of the top of the algae-blocking embankment is higher than the water surface; a plurality of flow pushing devices are arranged in the algae guiding ditch at intervals; the two endsof the alga guiding ditch are respectively provided with a gate; and the artificial wetland is positioned in an area surrounded by the algae-blocking embankment and the embankment. According to the surrounding separation system, the algae removal and ecological restoration are combined, no negative influence is caused to the environment, the surrounding separation system can be applied to a largewater area, is relatively high in algae removal efficiency, algae substances in the water body do not need to be fished manually, the labor intensity of workers is reduced, and meanwhile, the algae substances in the water body can be salvaged by replacing other energy consumption equipment.

The invention discloses a chitosan-modified clay method and its application in algae removal technology; the clay is modified with 0.2-2 mg / mL dilute acid chitosan solution, and the modified clay and traditional coagulant are in a mass ratio of 1 :2~2:1 compounding, by adding cationic surfactants to increase the stability of dissolved air water bubbles and enhance the hydrophobicity of algae, the components of several agents are compounded with each other to produce a synergistic effect. The composite coagulant of the invention has fast flocculation speed, strong adsorption bridging ability and low cost, and does not contain harmful components to human body. The modified clay and coagulant prepared in the previous stage are compounded and added, and the surfactant is added under stirring, and most of the algae in the water are removed through the dissolved air flotation device. After the raw water is dosed, the dissolved air flotation method is used for solid-liquid separation, and the content of chlorophyll a (Chl‑a) can be reduced to 5 μg / L, and the removal rate can reach more than 95%.

The invention discloses a method for controlling algae in water, which comprises the following steps: (1) adding a reducing agent to the water to-be-treated, wherein the reducing agent is selected from one of sulfite, pyrosulfite, thiosulfate and sulfide, and controlling the dissolved oxygen in water to be less than 2 mg / L, wherein the treatment time is 0.5 to 20 minutes; and (2) placing the watertreated in step (1) in a closed reactor, controlling the dissolved oxygen in the water to be less than 0.5 mg / L, and performing ultraviolet irradiation treatment; or treating the water to-be-treatedby neocaridina denticulata biological treatment, and performing further processing by the steps (1) and (2). The control method of the invention can achieve effective removal and thorough control of algae cells safely, economically, efficiently and stably.