KR100993009B1 - Rapid removing method of algaes, suspended solid and nutrient salts by using potential difference method - Google Patents

Abstract

The present invention relates to a method of continuously removing phosphate, which is the cause of eutrophication, while simultaneously removing algae generated in water and suspended solids in wastewater at high speed, and more particularly, an inorganic salt and a polymer that provide a positive charge. When the modified magnetic powder is injected into the water or wastewater where the algae is generated and shaken, the green algae and suspended solids that are negatively charged are adsorbed to the surface of the magnetic powder that is positively charged by the potentiometric method, Phosphate in ionic state reacts with inorganic salts to form insoluble phosphate which is a floating material, and supplies external magnetic force to remove algae and suspended matter generated in water as well as phosphate which is eutrophication at the same time. It is about a method.

Potentiometric method, algae, suspended solids, phosphate

Description

Rapid removing method of algaes, suspended solid and nutrient salts by using potential difference method}

The present invention relates to a method for continuously and simultaneously removing phosphate, which is the cause of eutrophication, while removing algae generated in water and suspended solids in wastewater at high speed.

The eutrophication of freshwater lakes in Korea rapidly progressed in the late 1980s when the size of livestock and inland aquaculture fishery increased, and many lakes changed into eutrophic lakes. As a result, even in lakes where no algae appeared in the past, blue algae appeared in summer and colored the lake green, causing damage such as increasing organic concentration, odor of tap water, and proliferation of toxic algae. It is becoming. Accordingly, in order to prevent eutrophication of freshwater lakes, not only sewage treatment but also non-point source management such as livestock manure and fertilizer should be focused. The outflow of nutrients from nonpoint sources is concentrated during several heavy rains per year and rarely during the dry season. During heavy rains, the flow rate of the lake inflow is very large and therefore cannot be disposed of once it has been discharged from the land. Therefore, in order to prevent eutrophication, the construction of sewage treatment plants cannot be expected to be effective, and at the same time, comprehensive land management that suppresses erosion and runoff of basin soils should be carried out.In farmland, it is possible to incline fields that have steep slopes to prevent photo erosion. Investors need to invest in the development of environmentally-friendly agricultural technologies, such as cutting down on tillage and making the furrows in the contour.

In order to remove algae generated in freshwater lakes, the soil is sprayed and then sedimented with a cutlery. A fine air generator is mounted on the cutlery and the algae are floated and removed together with copper. ^{2 +} ) killing by heavy metal spraying, killing by fungicides such as sodium chloride (NaClO), and other inorganic oxides such as zeolites are removed, but most methods use a method of precipitation by means of a cutlery Among them, the most widely used method employs a method of spraying ocher powder and sedimenting simultaneously with algae for economic reasons. However, algae that have sunk in the water is composed of organic matter, and due to the low self-cleaning ability of the natural environment, the rotting microorganisms decay in the anaerobic atmosphere of the water can cause an increase in BOD and COD. As a result, there is a high possibility of secondary water pollution, which may destroy the water ecosystem.

In addition, some air bubbles are used to remove and float above the surface of the water. However, algae can be removed only from local waters, so it is not very effective to remove algae from a wide range of waters. Therefore, the methods for removing algae have been mobilized with high probability or very limited method of threatening the water ecosystem.

In order to prevent water deterioration during the algae removal process, and to remove it more efficiently, Korean Laid-Open Patent Publication No. 2004-0002370 generates ozone efficiently by an ozone generator to generate this ozone. As a generator, the microbubble is injected into and contacted with water to ensure high dissolution rate of ozone, and decomposes organic matters in water by using strong oxidizing and sterilizing properties. Water Purification Method is proposed by using microbubble ozone to reduce green algae and prevent the occurrence of green algae or red tide, and Korea Patent Publication No. 2005-0003314 has a buoyant body equipped with a nozzle for ejecting fine bubbles. To the barge and place the barge anywhere the green algae occurred, In firmly and proposes a removable algae removal apparatus to remove, Korea Patent Publication No. 2004-0110350 call to take on a + charge on the surface of the magnetite powder (Fe ₃ O ₄₎ surface nitride dog, electromagnetic naejineun the magnetic force of the permanent magnet Green algae, red tide control method and removal system that can remove algae in the water at a high speed by using-a negative charge on the surface of the algae and magnetite bearing the charge using the + charge and then permanent magnets or electromagnets A control method and a control system for removing algae using an attached conveyor belt have been proposed.

The Korean Patent Laid-Open Publication No. 2004-0002370 can exert oxidative and bactericidal effects in contact with organic matter, green algae, pathogens, etc. suspended in water by the strong oxidizing and sterilizing action of ozone, but can exert an effect on water purification. In addition to the limited effect of removing suspended solids, including algae generated in large quantities in the algae, there is a disadvantage that can only be very limited to remove algae generated in freshwater lakes or sea level while moving on the surface of the water. Patent Publication No. 2005-0003314 discloses an environment-friendly method of preventing secondary pollution by removing algae, which is a method of generating fine bubbles in the water and floating out of the surface and floating algae. When microbubbles ejected on the spoon surface take a long time to rise above the surface The door may be effective in a stop system, but has a disadvantage in that the efficiency of removing algae is low in a mobile situation. Korean Patent Laid-Open Publication No. 2004-0110350 uses aluminum salt on the surface of a magnetite (Fe ₃ O ₄ ) powder. It is not possible to provide a method of removing algae by potentiometric method by surface modification to have a positive charge, or to remove contaminated eutrophicates in water, and also to remove suspended solids or algae contained in water by real potentiometric method. The removal efficiency is high when the pH of the water is close to neutral in order to remove it. However, algae generated by eutrophication have ammonia nitrogen and water is alkaline and the removal efficiency drops rapidly. The problem is that it is too low to be used.

Accordingly, the inventors of the present invention have made a lot of efforts to improve the water environment based on the results of the prior application (application number: 10-2007-0087061, name of the invention: continuous removal and removal of algae and nutrients by the potentiometric method) When positively charged inorganic salts and polymer-modified magnetic powders are injected into the water or wastewater where algae are generated and shaken, negatively charged green algae, suspended solids and phosphates present in the ionic state in the water have potential differences. The present invention was completed by confirming that it can be adsorbed on the surface of a magnetic powder having a positive charge by a method and can be removed at high speed by using an external magnetic force.

Therefore, the present invention is to quickly remove the suspended solids contained in the waste water to secure the economics and workability of the company, and to quickly remove the green algae and red tide generated in freshwater lakes or sea level, as well as the removal of phosphate as a eutrophication cause by fundamental water quality In addition to protecting the environment, it is possible to minimize the economic damage of fishermen in fisheries and to secure the economic and workability of the company.

The present invention provides a reaction tank for removing algae and nutrients, a power unit mounted on or connected to the reaction tank to move the reaction tank, algae having a storage device for algae and nutrient precipitates connected to the opposite side of the reaction tank and In the continuous removal device of phosphate, the bottom of the reactor is in the water, the upper part is floated on the surface of the water, the inlet and algae and the algae and the algae and nutrients generated in the direction of the reactor flows At the end of the opposite direction is provided with an outlet for the nutrients are removed water is discharged, the reactor is provided with a nutrient concentration measurement device and a hydrogen ion concentration measuring device of the water flowing into the reactor inlet, the positive inlet to the reactor Each of the above-mentioned modifications to a surface modified magnetic composite feeder, an acid and alkali feeder, a reactor or a power plant. In accordance with the algae, nutrients, and the pH value measured in the measuring device is characterized by the continuous apparatus for removing algae and phosphate comprises a control device for controlling the feed rate of the magnetic complexes, acid or alkali.

In another aspect, the present invention comprises the steps of measuring the algae concentration, nutrient concentration and hydrogen ion concentration of the water flowing into the reactor at the inlet of the reactor while moving the algae and phosphate continuous removal device; Supplying the surface-modified magnetic complex, acid or alkali to have a positive charge according to each concentration; Solid-liquid separation separating the algae and nutrients attached to the magnetic complex powder in the reactor by filtration or magnetic force, and discharging water to the outlet of the reactor; There is another feature in the continuous removal method of algae and phosphate comprising a.

Hereinafter, the present invention will be described in detail.

The present invention continuously removes algae according to the potentiometric method while artificially moving along the contaminated water in algae or sea level, and at the same time removes the eutrophication of phosphate, which is the cause of algae generation, is filtered or applied to external magnetic force. This can prevent water degradation caused by algae or phosphates by a continuous system.

Continuous removal device of algae and phosphate of the present invention is a reaction tank for removing algae and nutrients, a power unit mounted on or connected to the reaction tank to move the reaction tank, algae and nutrients connected to the opposite side of the reaction direction of the reaction tank It is equipped with a deposit storage device.

When the reaction tank of the present invention moves in water, the bottom is present in the water, the upper part is injured on the water surface, and for this purpose, the upper part of the reactor is injured 10 above the surface as shown in FIG. The part may be configured to be equipped with a buoy 11 that can float on the top of the reactor to achieve the structure to be deposited.

In addition, the reaction tank of the present invention has an inlet through which the algae and the nutrients generated water flow in the direction in which the reaction tank moves and an outlet through which the algae and the nutrients have been removed.

The shape of the cross section cut perpendicular to the moving direction of the reactor is U-shaped so that the insoluble suspended solids formed after the reaction between the surface-modified magnetic complex powder and the nutrients to provide positive charges do not sink into the spoon. It is preferable as a structure to make.

The reactor is preferably elongated in the direction of movement so as to give sufficient time to remove the algae and nutrient generated water, and a plurality of unit reactors are connected between the connecting portions to facilitate movement in a narrow space. It may be left connected to and long.

In addition, the reaction tank is preferably provided with a bubbler (bubbler) or a stirring device that can generate fine air at the bottom of the reaction tank to increase the contact time and reaction time for removing algae and nutrients. The stirring device may be configured as a screw or impeller type 9 of FIG. 1.

The reaction tank is preferably provided with a magnetic complex surface-modified with a positive charge of the present invention, an acid or alkali supplying device, a concentration measuring device of a spirit salt and a hydrogen ion concentration measuring device according to the concentration of algae, nutrients, hydrogen ions. Also preferably provided with a device for measuring the concentration of algae, nutrients, hydrogen ions of the water discharged to the reactor outlet.

The positively charged magnetic complex, acid or alkali may be diluted in water and supplied through a high pressure nozzle in a solution or dispersed phase.

In the surface-modified magnetic complex, algae and suspended substances contained in the water are adsorbed by the mechanism as shown in FIG. 2. In this case, the spray amount of the magnetic complex powder may vary depending on the size of the reaction tank for removing algae and suspended solids and the flow rate flowing into the reaction vessel, and may vary according to the amount of contamination of the algae and suspended solids. Spray concentration of the magnetic complex may be included 0.01 to 5.0 parts by weight based on 100 parts by weight of water in the reaction tank, preferably 0.1 to 2.5 parts by weight, more preferably 0.25 to 2.5 parts by weight However, even if the surface of the magnetic composite is modified to provide a high positive charge when the amount of the spray is less than 0.01 parts by weight, the removal efficiency is insufficient because the ability to remove negatively charged algae and suspended solids by the potentiometric method Very low or non-removable problems can occur, and exceeding 5.0 parts by weight not only takes a lot of time and expense to recycle the composites treated with algae and suspended solids, but also excessive logistics costs to transport large quantities of magnetic complexes. It is desirable to spray at the concentration suggested above because it has the disadvantage of All.

In order to automatically adjust the hydrogen ion concentration (pH) of the reaction tank, it is necessary to equip the reaction tank with each acid storage container, an acid and alkali supplying device having an alkali storage container so as to supply an acid or an alkali to the reaction tank. The hydrogen ion concentration is preferably adjusted so that the pH of the reaction tank is in the range of 7 to 9.5. As ammonia nitrogen is generated by a large amount of algae generated by eutrophication, the water quality changes to alkali, and the pH of the water quality is alkali. In one case, since the removal rate of algae and suspended solids can be greatly reduced by the potentiometric method of the present invention, it is automatically adjusted by the controller to maintain the pH range.

When removing algae from the reactor, the magnetic complex surface-modified to be positively charged is easily attached by the potentiometric method as iron adheres to the magnet while in contact with the negatively charged algae. When phosphate, an eutrophic substance in water, is removed, an insoluble metal phosphate is formed by the modified inorganic salt on the surface of the magnetic powder, and is attached to the magnetic complex by an excess inorganic salt. The algae and metal phosphates attached to the magnetic complexes are connected to the reaction vessel and the storage device by means of a filtration or magnet-liquid separation device, for example, a wheel with a conveyor belt for supplying magnetic force of FIG. 1. After solid-liquid separation, a scraper or blade 13 is finally installed on the rotating body of the wheel in the storage device 2 so that suspended matter floating in algae or water generated on the barge can be continuously removed.

The magnetic composite is generally used in the art, and is not particularly limited, and any magnetic material may be used. In the present invention, in particular, a hard or soft type of ferrite, magnetite (Fe ₃ O ₄ ) or iron (Fe) powder is used, but preferably, the price is low, and the production of fine powder It is preferable to use a magnetite or soft type ferrite which is easy, has excellent acid resistance, and is convenient for recycling the magnetic composite. It is preferable to recycle the magnetic complex by desorbing the attached algae, and the recycling method may be selected by a pyrolysis method or a fermentation method. In the case of the hard type ferrite powder, when the external magnetic force is applied to the powder treated in the reaction tank of the present invention, it does not lose its magnetism, such as permanent magnets. It is advantageous to use a pyrolysis method that decomposes algae by pyrolysis by heating to a temperature of 450 ~ 650 ^o C with excellent dispersibility in water, and in order to recycle the magnetic complex of soft type ferrite, magnetite and iron powder It is advantageous to use fermentation method rather than pyrolysis method which has a large heat loss because it does not retain magnetism even when magnetic force is applied.

Particles of the magnetic complex are preferably a fine powder that can be sized in order to widen the specific surface area that can be in contact with algae or suspended matter in water, specifically 0.1 μm to 1 mm range, preferably 0.1 μm to 100 μm range More preferably, it is better to maintain the range of 0.1 to 5 μm. If the particle size of the powder is less than 0.1 μm, the specific surface area becomes larger and the likelihood of adsorption of suspended solids in the water is increased. As the resistance to water is generally increased, the solid-liquid separation can be difficult by the storage device on the rear side of the reactor and the magnet at the connection part, and it is difficult to prepare fine particles of the magnetic complex. It costs a lot of manufacturing cost, and if it exceeds 1 mm, the specific surface area is small and the sedimentation speed is high. There is a problem in that the probability of adsorption by contact is relatively low.

Surface modification of the magnetic complex for providing a positive charge on the surface of the magnetic powder may be used alone or mixed with an inorganic salt and a polymer.

The inorganic salt modified on the magnetic powder surface is at least one selected from ferric sulfate, aluminum sulfate, polyaluminum chloride (PAC), aluminum chloride. One or more kinds of the inorganic salts selected are used in the range of 0.15 to 18 parts by weight, preferably 0.25 to 15 parts by weight, more preferably 0.5 to 12 parts by weight, based on 100 parts by weight of the magnetic composite.

If the amount is less than 0.15 parts by weight, the amount of positive charges on the surface of the magnetic particles is small, it is not easy to remove the negatively charged suspended solids, algae in the water, and it is difficult to remove the phosphate dissolved in the water, if the amount exceeds 18 parts by weight As the inorganic salts are acidic, it is desirable to maintain the concentration because there is a fear of dissolving the magnetic powder during the reforming process and the price competitiveness may be lost.

The polymer modified on the surface of the magnetic powder may be a natural polymer chitosan or a polymer coagulant. In the case of chitosan, the material obtained by deacetylating the chitin contained in crab, crayfish, and shrimp shell to 60% or more, preferably 80-98% can be used. At this time, the molecular weight of the chitosan is preferably in the range of 10,000 to 250,000, preferably in the range of 10,000 to 100,000, more preferably in the range of 30,000 to 70,000. If the molecular weight is less than 10,000, since the potential of positive charge is lowered when reforming on the surface of the magnetic complex, it is possible to provide a low adhesion rate for the algae or floating material having a negative charge by the potentiometric method. It is advantageous to maintain the above range because a problem arises that the efficiency of workability decreases due to viscosity swelling during dissolution. In the chitosan coating, which has a positive charge on the surface of the magnetic composite powder according to the present invention, after dissolving the chitosan in a solvent, the magnetic composite powder is deposited to coat the surface, and then mixed with the magnetic composite through a drying process of the solvent. A magnetic composite powder having a positive charge property on its surface is prepared.

As the solvent of the chitosan, an acid such as an organic acid or an inorganic acid is used. Specifically, lactic acid, citric acid, acetic acid, sulfuric acid, hydrochloric acid, phosphoric acid and nitric acid may be used. At this time, it is advantageous to use sulfuric acid, lactic acid and citric acid to prevent odor discomfort or respiratory disease when depositing the magnetic composite powder for the positive charge, and acetic acid is used to prevent environmental pollution by the by-product after coating It is more preferable to do. The chitosan is used in the range of 0.25 to 12 parts by weight, preferably 0.5 to 10 parts by weight, and more preferably 1.0 to 5.0 parts by weight with respect to 100 parts by weight of the magnetic complex, and the amount of the magnetic particles is less than 0.25 parts by weight. Due to the small amount of positive charge on the surface, it is difficult to easily remove suspended solids that carry negative charges in the water.When it exceeds 12 parts by weight, it is difficult to provide a positive charge any more and the surface modification process is required, which may cause a loss of competitiveness. do.

In addition, the polymer coagulant which has a positive charge on the surface of the magnetic composite powder according to the present invention may be used by selecting one or more of polyacrylamide-based or polyamide-based, cationic, nonionic, and anionic Among the systems, it can be used except for anion system. As the polymer coagulant, polyacrylamide, polyamide, polyamine, polydiallyldimethylammonium chloride (polyDADMAC), polyethyleneimine acetate, polyethyleneimine, etc. may be used, and most preferably used in wastewater treatment plants. It is advantageous to use polyacrylamide or polyamide polymer coagulant.

In order to provide a positive charge to the present invention, the polymer coagulant used for surface modification of the magnetic composite may modify 0.05 to 5.5 parts by weight based on 100 parts by weight of the magnetic composite powder, preferably 0.2 to 3.5 parts by weight, More preferably, the amount is 0.5 to 2.0 parts by weight. If the amount is less than 0.05 parts by weight, the amount of positive charge is less on the surface of the magnetic composite, so that it is difficult to easily attach negatively charged algae or suspended solids, and when it exceeds 5.5 parts by weight, It is difficult to provide a positive charge, and it is very difficult to obtain a surface-modified magnetic composite having a uniform distribution as it becomes very viscous when dissolved in a solvent. A problem arises.

When separating the magnetic complex by magnetic force, the magnet required for this is not particularly limited, and it is possible if the surface-modified magnetic complex attaches green algae, suspended matter, and eutrophication material by the potentiometric method, and then has good solid-liquid separation by the magnet. You can do it. The magnet may be a permanent magnet having 1,000 to 3,500 gauss or an electromagnet having 2,500 to 15,000 gauss.

The power unit for moving the reactor by being attached to or connected to the reactor of the present invention includes algae and flotation by the potentiometric method by sufficient power and continuous method to move the reactor and its associated storage device to the algae generating area. There is no particular limitation as long as it can supply sufficient electricity required for adsorption and desorption of the material, and in a preferred embodiment, the general vessel 5 of FIG. 1 can be used.

The algae and nutrient precipitate storage device connected to the opposite side of the reaction direction of the reaction tank of the present invention is to store suspended matter such as algae and nutrients such as nutrient precipitates treated in the reaction tank until transported to the land, in an embodiment May be in the form of barge 2 of FIG.

As described above, if the algae is removed by a conventional method, the sedimentation of the algae or the limited treatment in a narrow water area not only greatly reduce the economic efficiency, but also the algae decay in the anaerobic atmosphere submerged in the water, further improving the water quality. There is a problem of deterioration, while removing the suspended solids from the waste water takes a long time to separate the solid-liquid separation and lose the competitiveness of the company for water treatment, algae generated in the water by the automation system by the potentiometric method according to the present invention ) To remove the phosphate, which is the cause of eutrophication, at the same time and to remove the green algae and red tide generated in freshwater lakes or the sea surface, thereby minimizing the economic damage of fishers in the fisheries industry as well as protecting the water quality. Quickly remove suspended solids contained in wastewater There is a great advantage in securing economy and workability.

Hereinafter, the present invention will be described in more detail with reference to the following examples, which are not intended to limit the present invention.

Example  One

The suspended solids contaminated in waste water may have different results due to the different suspended solids content depending on the time of discharge and the manufacturing environment, despite the same establishment. Therefore, in the present invention, in order to confirm the reproducibility of the accurate result, the ocher 3g / L artificially added to the tap water and then shaken to prepare a uniform 0.3% ocher (Cochang ocher Co., Ltd.) floating material sample of the embodiment of the present study Used as.

Magnetic powder was used magnetite (Fe ₃ O ₄ ), a black pigment provided by Bogwang Chemical Co., Ltd., and hard type isotropic ferrite of Toda ferrite Korea Co., Ltd. was used. To 100 parts by weight of the magnetic complex, surface modification of the aluminum sulfate (Al ₂ (SO ₄ ) ₃ 14-18 H ₂ O; Tongyang Steel Chemical) for reagents with an inorganic salt on the surface of the magnetic powder was carried out, and acryl was used as a polymer. The polymer of amide was surface modified to 0.20 parts by weight.

After the addition of a surface-modified magnetic composite with organic-inorganic polymers to a sample of optionally prepared ocher suspended solids, the optimum conditions for removing suspended solids according to the present invention were confirmed.

First, a 1 L measuring cylinder was filled with tap water, and 3 g of ocher was correctly added, followed by shaking to prepare an artificially contaminated sample of ocher. Then, 5 g of each of the prepared surface-modified magnetic composites was added, and after shaking, the pH was changed to 5.0, 6.0, 6.5, 7.0, 7.5, 8.0, 9.0, and 10 in order to confirm the effect of removing suspended solids according to pH. After precisely adjusting, neodymium magnets were added to separate the suspended solids at high speed, and the analysis results are shown in Table 1.

Sample Name Settling time
(sec) Turbidity
(NTU) Heavy metals other
(ppm or less) Magnetite Blank 1800 or more 76.3 0.1 pH 10 More than 1200 17.7 0.1 pH 9.0 364 5.94 0.1 pH 8.0 228 4.90 0.1 pH 7.5 211 4.48 0.1 pH 7.0 201 3.98 0.1 pH 6.5 218 4.21 0.1 pH 6.0 432 4.88 0.1 pH 5.0 More than 1200 21.8 0.1 Ferrite Blank 1800 or more 74.2 0.1 pH 10 More than 1200 15.4 0.1 pH 9.0 342 5.04 0.1 pH 8.0 202 4.52 0.1 pH 7.5 179 4.18 0.1 pH 7.0 170 3.68 0.1 pH 6.5 204 3.92 0.1 pH 6.0 364 4.25 0.1 pH 5.0 More than 1200 20.4 0.1

In Example 1, magnetic powders (Magnetite and Ferrite) and ocher suspended solids settled at a relatively high speed by excellent adsorption by potentiometric method in a wide range between pH 6.5 and 8, and also after turbidity (Turbidity) A relatively low result was confirmed. In particular, sedimentation rate and turbidity according to pH showed the best results at pH 7 ~ 7.5, whereas adsorption was not performed well by the potentiometric method below pH 6 or above pH 9. It was found that the sedimentation rate was very weak due to low temperature.

As a result of observing the process of adsorption formation and sedimentation by the potentiometric method between pH 6.5 and pH 8, most of the formed flocs have sufficient specific gravity to settle and can settle relatively quickly, Adsorbents were suspended in water for a long time due to insufficient specific gravity to settle, and it was confirmed that heavy metals contained in water were not affected by heavy metals due to pH of 0.1 ppm or less.

Example  2

The pH of the artificially made 3% yellow soil water is fixed at 7.5, and the amount of the surface-modified magnetic complex is 0.5g (0.05wt%), 1g (0.1wt%), 2g (0.2wt%), 5g (0.5) Except for the addition of 10% (wt%), 10g (1wt%), 20g (0.2wt%), 50g (0.5wt%) was carried out in the same manner as in Example 1, depending on the amount of the surface-modified magnetic complex Table 2 shows the results of the analysis of the number of suspended solids.

Sample Name Turbidity
(NTU) heavy metal
(ppm or less) Magnetite (wt%) Blank 76.3 0.1 0.05 6.27 0.1 0.1 4.41 0.1 0.2 3.43 0.1 0.5 4.21 0.1 1.0 5.07 0.1 2.0 5.02 0.1 5.0 6.65 0.1 Ferrite (wt%) Blank 74.2 0.1 0.05 6.96 0.1 0.1 4.51 0.1 0.2 4.02 0.1 0.5 4.18 0.1 1.0 4.98 0.1 2.0 5.23 0.1 5.0 5.96 0.1

In Example 2, turbidity analysis showed that the turbidity was relatively high when the amount of the magnetic complex was added too much or too little, and the turbidity was lowest when 0.2 wt% was added. When the amount of the magnetic complex is added, a large amount of magnetic powder does not completely form adsorption by the potentiometric method, and some of it is suspended in water, causing turbidity, and when the amount of the magnetic complex is too small, all of the yellow soil is magnetic. Due to the lack of adsorption with the complex, a part of the loess is suspended in the water, which is believed to cause turbidity. Experimental results of the present invention showed the best results when the addition of 0.2% by weight, but in view of the efficient recovery of suspended solids for the purpose of the magnetic complex of the present study, it can be seen that it is advantageous to add the minimum amount of the magnetic complex there was. When considering the solid-liquid separation and the like as a result of the turbidity analysis and the sensory method of the experimental results of the present invention, the amount of the magnetic complex for solid-liquid separation of the suspended solids of 0.3% aqueous ocher solution can be used in the range of 0.2 to 0.05% by weight, It was confirmed that the amount of addition of the magnetic complex could vary depending on the concentration of the suspended solids.

Example  3

Green algae medium (Allenmedia, 1968) was prepared to confirm the removal rate according to the present invention in algae generated in the water was used by culturing the algae of Microcystis in a plastic house irradiated with sunlight. At this time, the pH of the green alga showed an average of 9.3.

The magnetic powder was used in the same manner as in Example 1, and the surface modification of ferric sulfate was 0.85 parts by weight based on 100 parts by weight of the magnetic composite, and the surface of the acrylamide was 0.10 parts by weight. It was.

After the addition of the surface-modified magnetic complex with organic-inorganic polymer to the aqueous solution of the cultured green algae, the optimum green algae removal condition according to the present invention was confirmed.

First, fill the cultured green algae in a 1 L measuring cylinder, add 5 g of each of the prepared surface-modified magnetic complexes, and shake the pH to determine the effect of removing suspended solids according to pH. , 8.5, 9.0, 9.5, 10, and 10.5 were precisely adjusted, and neodymium magnets were added to separate green algae generated at high speed. The results of the analysis are shown in Table 3.

Magnetic complex type pH Analysis item Turbidity
(NTU) Chlorophyll a
(ppb) TN
(ppm) TP
(ppm) COD
(ppm) Heavy Metals as Pb SS
(ppm) Recovery
(%) pH Magnetite Blank (1)
pH 9.34 17.9 232 202.5 4.35 9.47 N.D. 46.8 - 8.35 7.0 7.23 8.20 182.4 0.01
Below 8.97 N.D. 7.8 99.87%
More than 5.84 7.5 6.17 -2.51 188.6 0.01
Below 10.0 N.D. 7.0 99.88%
More than 5.77 8.0 6.26 1.90 177.6 0.01
Below 9.38 N.D. 6.8 99.89%
More than 5.47 8.5 7.04 1.15 177.6 0.01
Below 9.41 N.D. 10 99.83%
More than 5.99 9.0 4.61 0.74 184.3 0.01
Below 9.09 N.D. 7.2 99.88%
More than 5.71 9.5 4.53 5.78 179.7 0.01
Below 9.55 N.D. 9.4 99.84%
More than 6.75 10 12.3 169 167.5 0.25 9.71 N.D. 29.4 99.51%
More than 7.65 10.5 17.6 272 189.7 1.9 10.0 N.D. 42 99.30%
More than 9.81 Ferrite Blank (2)
pH 9.25 16.7 328 204.3 5 10.3 N.D. 51.2 - 8.86 7.0 13.0 93.7 176.7 0.05 8.54 N.D. 31.2 99.48%
More than 6.31 7.5 14.2 91.3 181.2 0.01 8.77 N.D. 36.4 99.39%
More than 6.93 8.0 13.9 100 178.5 0.08 8.95 N.D. 36.4 99.39%
More than 6.58 8.5 12.9 68.7 173.7 0.04 7.92 N.D. 35.6 99.41%
More than 6.29 9.0 14.1 121 197.6 0.2 8.94 N.D. 44.8 99.25%
More than 6.59 9.5 18.0 196 182.2 0.5 8.99 N.D. 58 99.03%
More than 6.97 10 25.2 316 179.7 0.85 9.07 N.D. 92.8 98.45%
More than 8.45 10.5 29.5 324 183.2 2 9.51 N.D. 116 98.07%
More than 9.88 week; N.D. means non-detectable and the detection limit is 0.1 ppm.

The removal rate of green algae according to the pH change of the cultured algae in Example 3 was much better than that of Ferrite, which was confirmed not only in the organoleptic method but also in the recovery of turbidity, chlorophyll a, suspended solids and magnetic complexes. Particularly, the sensory method showed that Magnetite had good dispersibility in water after adding to the measuring cylinder, but did not settle well due to combination with green algae. Because of the strong bonding, the green algae and the magnetic complex were not separated even in the moderate impact. On the other hand, Ferrite was weaker than Magnetite, while the ability to settle with green algae was superior to that of Magnetite, but it was found to be easily separated from green algae even with a small impact due to its weak bonding power. This means that the magnetite found in this experiment can support the result that green algae removal rate is better than Ferrite. In the range of pH of the algae water to remove the algae, the magnetite showed excellent results in the pH range of 7 to 9.5, and the ferrite showed excellent results in the pH range of 7 to 9.0.

The analysis of turbidity, chlorophyll a, TP (total phosphorus), and SS (underwater) in the optimum pH range showed a clear change before and after the addition of the magnetic complex, showing that magnetite showed a larger change than Ferrite. Could. In particular, chlorophyll-a and total phosphorus showed that the removal rate was almost 99% or more, so that the algae-producing eutrophication materials were simultaneously removed at the time of removal of the algae, thereby preventing or preventing the occurrence of the underlying algae. .

Ferrite showed higher levels of turbidity and SS than untreated blanks from pH 10 and above. This is because the specific surface area of the ferrite is relatively small due to the agglomeration of the fine particles of the ferrite that have not been recovered with the green algae and other suspended substances in the water, and the amount of the particles in the water due to other reactions. In the case of nitrogen, the removal rate was very low even after treatment by the method of the present invention.

NH ₄ ⁺ in water Or NO ₃ ^- is not likely to reduce total nitrogen because it is difficult to produce insoluble materials by reacting with inorganic salts or polymers used for surface modification. In order to remove nitrogen in water, activated sludge is mainly used in wastewater treatment plants.

Example  4

The pH of the cultured green algae was fixed at 7.5, and the amount of the surface-modified magnetic complex was 1 g (0.1 wt%), 2 g (0.2 wt%), 3 g (0.3 wt%), 4 g (0.4 wt%), and 5 g. (0.5wt%), 6g (0.6wt%), 8g (0.8wt%), 10g (1wt%) was added in the same manner as in Example 3 and the amount of the surface-modified magnetic complex The results are shown in Table 4. However, it can be seen that the concentration of the green alga of the sample is different from that of Example 3 depending on the culture state of the green algae.

magnetism
Complex
Kinds magnetism
Complex addition amount
(g) Analysis item Turbidity
(NTU) Chlorophyll a
(ppb) TN
(ppm) TP
(ppm) COD
(ppm) heavy metal
as Pb SS
(ppm) Recovery
(%) pH Magnetite Blank (1) 27.5 539.3 201.6 2.25 9.35 N.D. 68
9.80 One 12.1 30.0 151.3 0.01
Below 8.99 N.D. 41.2 95.88
More than 7.09 2 8.17 28.7 150.1 0.01
Below 9.96 N.D. 26 98.70
More than 7.23 3 7.08 20.1 197.65 0.01
Below 9.37 N.D. 22.4 99.25
More than 7.15 4 6.11 22.3 151.9 0.01
Below 8.15 N.D. 20 99.50
More than 7.09 5 6.51 23.3 199.7 0.01
Below 8.66 N.D. 21.2 99.58
More than 7.25 6 6.85 23.7 149.1 0.01
Below 9.15 N.D. 23.6 99.61
More than 7.22 8 6.18 25.9 197.45 0.01
Below 9.58 N.D. 19.6 99.76
More than 7.35 10 6.48 20.6 211.55 0.01
Below 9.82 N.D. 19.2 99.81
More than 7.12 Ferrite Blank (2) 14.5 376.2 190.7 4.85 8.15 N.D. 50.4
9.20 One 18.2 153.4 194.5 0.19 9.91 N.D. 77.2 92.28
More than 7.35 2 17.6 144.9 192.7 0.20 7.46 N.D. 74.4 96.28
More than 7.41 3 17.0 141.1 176.1 0.19 7.5 N.D. 67.6 97.75
More than 7.40 4 15.9 134.9 193.05 0.20 8.11 N.D. 64.4 98.39
More than 7.46 5 15.9 127.9 199.9 0.18 7.79 N.D. 62.4 98.75
More than 7.44 6 13.8 104.0 154.25 0.18 7.73 N.D. 55.6 99.07
More than 7.47 8 14.2 104.0 202.35 0.18 8.66 N.D. 49.2 99.38
More than 7.47 10 13.9 107.9 196.9 0.18 7.93 N.D. 47.6 99.52
More than 7.50 week; N.D. means non-detectable and the detection limit is 0.1 ppm.

Experimental results according to the present invention in Example 4, the magnetite showed a better effect than Ferrite as a whole.

Turbidity, chlorophyll a, total phosphorus, and suspended solids showed excellent removal rate, but there was no tendency to remove total nitrogen and chemical oxygen demand according to the amount of magnetic complex added. There was also a tendency to increase than the blank without addition of this surface modified magnetic complex. Depending on the concentration of green algae or suspended solids, the amount of addition of magnetic complexes used may vary.In order to increase the removal rate of green algae or suspended solids contained in water, it is necessary to increase the amount of surface modification of the magnetic complexes or to influence complex media in water. After preliminary investigation, it is necessary to remove the algae and suspended solids contained in the water.

Example  5

A 130 cm × 23 cm × 20 cm clear acrylic reactor was fabricated for green algae and phosphate removal experiments by a continuous system. A flow meter was installed to control the flow rate of the green algae water contaminated with the green algae at the inlet of the reactor, and experimented by constructing an automated system that can adjust the pH using the surface-modified magnetic composite powder prepared in Example 1 In order to separate the green algae attached to the magnetic complex by the potentiometric method from the external magnetic force, a magnet was attached to the end of the reactor. The treated water after the solid-liquid separation by the magnet was collected, and the treatment efficiency by the continuous system was confirmed. At this time, the inflow rate into the reaction tank was 2 liters / minute, and the amount of the surface-modified magnetic complex was added by the powder inflow apparatus so that the concentration of 0.5 parts by weight with respect to the green algae was adjusted. Adjusted to 7.0 by addition. In order to increase the contact time of the green algae and the magnetic complex, a bubbler for blowing air to the lower part of the reactor was provided.

Chlorophyll a (ppm) TP (ppm) Before treatment After treatment Before treatment After treatment 29 0.35 0.82 0.01 or less

Based on the experiment of the present invention as in Example 5, the result of the experiment using a continuous system, after surface modification to the magnetic powder to provide a positive charge and the green algae and phosphate adsorbed in the appropriate pH range, the external magnetic force It was confirmed that the problem of the method of sedimentation with a conventional cutlery can be sufficiently overcome by separating and removing using the same.

Comparative example  1 to 4

The same procedure as in Examples 1 to 4 was carried out except that the magnetic powder was not modified with an inorganic material and a polymer material.

As in Comparative Examples 1 to 4, the surface-modification not having a positive charge on the surface of the magnetic powder had little effect on the removal of algae as well as the floating material of the yellow soil.

Figure 1 is a three-dimensional view showing an embodiment of the continuous removal of algae and phosphate by the potentiometric method of the present invention.

Figure 2 illustrates a mechanism for removing algae or phosphates by the potentiometric method of the present invention.

FIG. 3 is a photograph before and after the treatment of adding 2 g (0.2 wt%) of surface-modified Magnetite in a static test to remove suspended solids in wastewater of Example 2. FIG.

Figure 4 is a photograph before and after the treatment in the stationary experiment to remove the cultured green algae using the potentiometric method according to the pH of Example 3.

5 is a photograph of a continuous system operated in an experiment to remove algae or phosphates by the potentiometric method of the present invention.

[Explanation of symbols on the main parts of the drawings]

1: U-shaped reactor 2: Barge (storage device)

3: connection part 4: control unit

5: boat (power unit) 6: nozzle

7: pH meter 8: bubbler

9: screw or impeller

10: Surface injury of U-shaped reactor 11: Buoy

12: wheel with conveyor belt for supplying magnetic force

13: blade

Claims (11)

Continuous removal device of algae and phosphate with a reaction tank for removing algae and phosphate, a power unit mounted on or connected to the reaction tank to move the reaction tank, algae and phosphate deposit storage device connected to the opposite direction of the movement of the reactor To The bottom of the reactor is in water, the upper part is floated on the surface of the water, the algae and phosphate is removed at the inlet and the opposite end of the inlet to which the algae and phosphate generated water flows in the direction to move the reactor It is provided with the outlet which flows out, The reactor is provided with an algae concentration measuring device, a phosphate concentration measuring device and a hydrogen ion concentration measuring device of the water flowing into the reactor inlet, The magnetic composite feeder, the acid and alkali feeder surface-modified positively charged to the reactor inlet, And a control device for controlling the supply amount of the magnetic complex, the acid or the alkali according to the concentration of algae, phosphate and hydrogen ions measured by the respective measuring devices to the reactor or power unit. The method of claim 1, A continuous removal device of algae and phosphates, characterized in that any one or more of the bubble supply device (bubbler) and the stirring device is provided on the bottom of the reactor. The method of claim 1, Apparatus for continuous removal of algae and phosphate, characterized in that the solid-liquid separation device by filtration or magnet at the connection portion of the reaction tank and the storage device. The method of claim 3, wherein The magnet is a continuous removal device of algae and phosphates, characterized in that the permanent magnet of 1,000 to 3,500 gauss or an electromagnet of 2,500 to 15,000 gauss. The method of claim 1, Apparatus for continuous removal of algae and phosphate, characterized in that the pH in the reactor is maintained 7 ~ 9.5. While moving the continuous removal of algae and phosphates of any one of claims 1 to 5 from the water surface, Measuring algae concentration, phosphate concentration and hydrogen ion concentration of water flowing into the reactor at the reactor inlet; Supplying the surface-modified magnetic complex, acid or alkali to have a positive charge according to each concentration; Solid-liquid separation of algae and phosphates attached to the magnetic composite powder in the reactor by filtration or magnetic force, and discharging water to the outlet of the reactor; Continuous removal of algae and phosphates comprising a. The method of claim 6, The magnetic composite is at least one selected from hard or soft ferrite, magnetite (Fe ₃ O ₄ ) and iron (Fe) powder, Particle size of the magnetic complex is a continuous removal method of algae and phosphate, characterized in that 0.1 ㎛ ~ 1 mm. The method of claim 7, wherein 100 parts by weight of the magnetic complex, polyacrylamide or polyamide-based cationic or nonionic polymer coagulant or chitosan 0.05 ~ 5.5 parts by weight of the surface removal method characterized in that the continuous removal of algae and phosphates. The method of claim 7, wherein Alkaline and phosphate salts, characterized in that 0.15 to 18 parts by weight of inorganic salts of ferric sulfate, aluminum sulfate, polyaluminum chloride (PAC), aluminum chloride, and ferric chloride are surface-modified in 100 parts by weight of the magnetic complex. Continuous removal method. The method of claim 8, The chitosan has a weight average molecular weight of 30,000 ~ 70,000, the deacetylation of chitin is 80 to 98%, characterized in that the continuous removal of algae and phosphates. The algae and phosphate attached to the magnetic complex separated by the magnetic force of claim 6 is pyrolyzed by heating to 450 ~ 650 ℃ or fermented by a microorganism, characterized in that the regeneration of the magnetic complex.

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