KR20190054627A - Method for preparing composition for removing green algae using oyster shell - Google Patents

Abstract

The present invention relates to a method for preparing a composition for removing green algae using an oyster shell, which comprises the steps of: (a) washing oyster shells using distilled water and an organic solvent; (b) drying the oyster shells of the step (a); (c) calcining the oyster shells of the step (b); (d) preparing the oyster shells of the step (c) as slurry; and (e) mixing the slurry of the step (d) with amphoteric starch. Accordingly, the method of the present invention has a very effective advantage of absorbing and removing phosphorus, nitrogen, and eutrophication materials included in green algae by using the oyster shells. In addition, when the oyster shells of the present invention is used as a raw material, the oyster shells, which are left on the seaside to cause pollution, are reduced, thereby reducing pollution of the seaside.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a composition for removing green algae using oyster shells,

The present invention relates to a method for producing a composition for removing green algae using oyster shells.

Generally, a green algae phenomenon refers to a phenomenon in which eutrophicated lakes or floating algae in a stream with a slow flow rate are massively proliferated and accumulated on the water surface, thereby changing the color of the water into green. Such a green algae phenomenon has serious adverse effects on fresh water, which causes serious problems such as visual effects, ecological problems due to toxins and human and livestock damage, ecosystem degradation, fish deficiency due to oxygen deficiency, and various aquatic organisms .

The red tide phenomenon refers to the phenomenon that the color of sea water changes in red color due to the proliferation of large amounts of phytoplankton. When the red tide is mostly caused by the flagella or diatoms but by the cucurbits classified as euglena or protozoa There are also often.

The red tide phenomenon is widely occurring all over the world and recently it has been widely spreading in the South Sea coast, the West Sea, and the southern coast of the East Sea in Korea. The cause of red tide is shifting from the diatom center to the center of the flagellated tide, and the concentration of red tide is becoming increasingly dense.

As the recent green tide or red tide phenomenon shows widespread, toxic, and prolonged, the pollution degree of nitrogen and phosphorus which cause green tide or red tide continuously increases, There is a desperate need for measures to minimize damage when red tide occurs.

To date, known methods of algae removal or red tide remediation include microorganisms, natural enemies, physico-chemical methods, and biological and chemical red tide removal methods have been evaluated as highly practical.

In other words, the physical method is a method of dredging or changing the sediments of land and farms, and all the wastes and pollutants in the land and farm are precipitated in the sediments to decompose, dissolving dissolved oxygen and producing various toxic substances . Therefore, the occurrence of red tide can be prevented in advance by dredging or changing the sedimentary layer. However, this method can have some effect when the target area is small, but its effectiveness is deteriorated when the target area is large.

The chemical method is a method of spraying a chemical to the oceans in which the red tide occurs and removing it by using a polymer coagulation method, a loess spraying method (clay adsorption method), an iron adsorption method, an ozone method, an ultrasonic treatment method, a bio- However, for industrial use, mass production, large-scale spraying, and undersea ecosystems should not be affected, transportation and use should be easy, and cost competitiveness should be ensured.

On the other hand, as a method of precipitating green algae using a polymer flocculant, there is a flocculation method using a coagulant of lime or aluminum salt and a metal salt (metal salt) to precipitate green algae and nitrogen phosphorus as an insoluble compound in water .

The lime as a coagulant is a method of reacting with phosphates and alkalis to generate and remove carbonate in addition to the phosphorus compound gelatin-like hydroxyapatite (Ca ₅ (OH) (PO ₄ ) ₃ ).

The sedimentation method using coagulant has a large variation of the greenhouse, nitrogen, and phosphorus removal efficiency depending on the reaction conditions, and it is difficult to maintain appropriate reaction conditions. In addition to the cost of the chemical agent and the disposal of the chemical sludge, .

KR 10-2017-0031421 A

It is an object of the present invention to provide a method for preparing a composition for removing green algae using an oyster shell capable of removing a green alga by a low cost and environmentally friendly method using an oyster shell.

The problem to be solved by the present invention is not limited to the above-mentioned problem (s), and another problem (s) not mentioned can be clearly understood by a person skilled in the art from the following description.

In order to solve the above problems, a method for preparing a composition for removing green algae using an oyster shell according to a preferred embodiment of the present invention comprises the steps of: (a) washing an oyster shell with distilled water and an organic solvent; (b) drying the oyster shell of step (a); (c) calcining the oyster shell of the step (b); (d) preparing the oyster shell of step (c) as a slurry; And (e) mixing the slurry and the amorphous starch in step (d).

In one embodiment, the organic solvent is preferably ethyl alcohol.

In one embodiment, the step (c) may further include a step of performing a first crushing step before the step (c), and a step of crushing a second crushing step after the step (c).

In one embodiment, the step (c) is performed in an electric furnace at 800 to 1,200 ° C for 1 to 4 hours.

In one embodiment, the step (d) is preferably milled in a high-density polyethylene container to produce a slurry.

In one embodiment, the milling is preferably milled at 80-150 rpm for 30-180 minutes using alumina balls 20-30 mm in diameter.

In one embodiment, the step (d) may be performed by mixing the oyster shell of the step (c) and distilled water at a weight ratio of 1:25 to 75 by mixing.

In one embodiment, in step (e), the amphoteric starch and the slurry of step (d) are mixed at a weight ratio of 1: 1 to 8: 1.

In one embodiment, the positive starch is at least one selected from the group consisting of corn starch, waxy corn starch, tapioca starch, potato starch, sweet potato starch, Sago starch, wheat starch, rice starch and high amylose starch It is preferably derived from starch.

The method for preparing a composition for removing green algae using the oyster shell according to the present invention has an advantage of being very effective in adsorbing and removing phosphorus, nitrogen and eutrophication substances contained in green tanks by using oyster shells.

In addition, when the oyster shell is used as a raw material according to the present invention, there is an advantage that the oyster shell which is left on the shore and causes pollution is reduced, so that coastal pollution can be reduced.

1 is a flowchart illustrating a method of preparing a composition for removing green algae using an oyster shell according to an embodiment of the present invention.
2 to 4 are graphs showing hydration activity of quicklime, dolomite dust powder and calcined oyster shell.
FIG. 5 shows the results of pH analysis according to the amount of the composition prepared according to Example 1 and Comparative Example 2. FIG.
FIG. 6 is an image showing the precipitation rate and turbidity, increasing the amount of the slurry prepared according to Example 1 and Comparative Example 2. FIG.
FIG. 7 is a graph showing an increase in the amount of slurry prepared according to Example 1 and Comparative Example 2 and an analysis of turbidity. FIG.
8 is a UV-VIS absorption spectrum for analyzing the microbial characteristics of the green algae solution to which oyster shell slurry prepared according to Example 1 is added.
9 is a graph showing the concentration of total phosphorus (TP) in the green algal solution according to the amount of the slurry prepared according to Example 1 and Comparative Example 2. FIG.
Fig. 10 shows an X-ray diffraction pattern of the oyster shell slurry produced according to Example 1. Fig.
FIG. 11 shows an X-ray diffraction pattern after the oyster shell slurry prepared according to Example 1 was reacted with the solution of the algae solution.
Figs. 12 and 13 show the results of measurement of COD and total phosphorus (TP), increasing the amount of oyster shell slurry prepared according to Example 1. Fig.
Fig. 14 shows the results of measurement of total nitrogen (TN) increasing the amount of amphoteric starch.
Figs. 15 to 17 show the results of measurement of total phosphorus (TP), total nitrogen (TN) and COD, increasing the amount of the composition for removing green algae prepared according to Example 2. Fig.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS The advantages and features of the present invention and the manner of achieving it will become apparent with reference to the embodiments described in detail below with reference to the accompanying drawings.

It should be understood, however, that the present invention is not limited to the disclosed embodiments, but may be embodied in many different forms and should not be construed as limited to the exemplary embodiments set forth herein. To fully inform the inventor of the category of invention. Further, the present invention is only defined by the scope of the claims.

Further, in the following description of the present invention, if it is determined that related arts or the like may obscure the gist of the present invention, detailed description thereof will be omitted.

Briefly explaining the oyster shell, the main element of the oyster shell is CaO, which can play an important role in forming a precipitate by the phosphorus and aggregation reaction contained in the wastewater.

The present invention provides a method for preparing a composition for removing green algae using an oyster shell according to an embodiment of the present invention.

1 is a flowchart illustrating a method of preparing a composition for removing green algae using an oyster shell according to an embodiment of the present invention.

Hereinafter, with reference to FIG. 1, a method for preparing a composition for removing green algae using an oyster shell according to an embodiment of the present invention will be described step by step.

The method for preparing a composition for removing green algae using an oyster shell according to an embodiment of the present invention comprises the steps of: (a) washing oyster shells using distilled water and an organic solvent (S100); (b) drying the oyster shell of step (a) (S200); (c) calcining the oyster shell of step (b) (S300); (d) preparing the oyster shell of step (c) as a slurry (S400); And (e) mixing the slurry and the amorphous starch in step (d) (S500).

In step (S100), the oyster shell is washed using distilled water and an organic solvent. In the method for preparing a composition for removing green algae using an oyster shell according to an embodiment of the present invention, the step (a)

The organic solvent may be at least one selected from the group consisting of C1 to C4 alcohols and combinations thereof, and specifically may be ethyl alcohol.

The oyster shell may be washed two to three times alternately using distilled water and an organic solvent, and the oyster shell is not limited thereto as long as it can remove the suspended substances present on the surface of the oyster shell.

In step (b), the oyster shell of step (a) is dried in step (S200), in the method of manufacturing a composition for removing green tea using oyster shell according to an embodiment of the present invention.

The step of drying the oyster shell in the step (a) (S100) may be performed by far infrared ray drying or vacuum drying, but is not limited thereto.

The far-infrared ray drying may be performed using a far-infrared ray dryer at 40 to 60 ° C for 4 to 8 hours.

The vacuum drying can be performed at a temperature of -45 ° C to -40 ° C for 1 to 5 days under a high vacuum of 1 mmHg or lower.

In the method of manufacturing a composition for removing green algae using an oyster shell according to an embodiment of the present invention, the step (c) (S300) is a step of calcining the oyster shell of the step (b) (S200).

The step (c) (S300) may be performed in an electric furnace at 800 to 1,200 ° C for 1 to 4 hours, and specifically, in an electric furnace at 1,000 ° C for 2 hours.

The step (c) (S300) may further include a second crushing step (S300) followed by the first crushing step (C) (S300).

The primary crushing step may be performed by filtering the crushed oyster shell so that the particle size of the crushed oyster shell is 100 μm or less. The secondary crushing step may be performed by the same method, but the particle size of the crushed oyster shell Is not more than 75 mu m.

The smaller the particle size of the crushed oyster shell is, the larger the surface area is, and the reactivity of the causal agent contained in the wastewater can be increased.

In step (d) (S400), the oyster shell of step (c) (S300) is prepared as a slurry by the oyster shell according to an embodiment of the present invention.

The step (d) (S400) may be performed by milling in a high-density polyethylene container to prepare a slurry.

The milling can be performed at 80 to 150 rpm for 30 to 180 minutes using alumina balls having a diameter of 20 to 30 mm, and specifically, at 160 rpm at 108 rpm using alumina balls having a diameter of 25 mm.

The milling may also be a wet milling.

The oyster shell of the step (c) S300 and the distilled water may be mixed and milled at a weight ratio of 1:25 to 75. More specifically, the step (d) (S400) Distilled water can be mixed and milled at a weight ratio of 1:50.

In step (e) (S500), the slurry of step (d) (S400) and the amphoteric starch are mixed in the method for preparing a composition for removing green tea using oyster shell according to an embodiment of the present invention.

The positive starch and the slurry of step (d) (S400) may be mixed at a weight ratio of 1: 1 to 8, and more specifically, the positive starch and the step (d) S400) can be mixed at a weight ratio of 1: 4.

The amphoteric starch is one derived from at least one starch selected from the group consisting of corn starch, waxy corn starch, tapioca starch, potato starch, sweet potato starch, Sago starch, wheat starch, rice starch and high amylose starch .

The method for preparing a composition for removing green algae using the oyster shell according to the present invention has an advantage of being very effective in adsorbing and removing phosphorus, nitrogen and eutrophication substances contained in green tanks by using oyster shells.

In addition, when the oyster shell is used as a raw material according to the present invention, there is an advantage that the oyster shell which is left on the shore and causes pollution is reduced, so that coastal pollution can be reduced.

Hereinafter, the present invention will be described in more detail with reference to Examples and Experimental Examples. However, the following examples and experimental examples are for illustrative purposes only and are not intended to limit the scope of the present invention.

Preparation of materials

The solution containing green algae, phosphorus and nitrogen used in the present invention was collected from Geum River near Okcheon, Korea. To sufficiently culture green algae, 11 g of K ₂ HPO ₄ and 5 g of NH ₄ NO ₃ were dissolved in 5,000 ml of distilled water To produce an eutrophication material.

Next, 500 ml of the solution was mixed with 5,000 ml of distilled water to prepare a diluted solution.

The diluted solution was incubated for 7 days in an incubator equipped with a continuous fluorescent lamp of 3,000 lux for 12 hours at a temperature of 30 DEG C for 12 hours and then dark for 12 hours.

The oyster shells used in the present invention were collected in a temporary shelter near the seaside near Geoje Island in Korea.

Example 1: Preparation of oyster shell slurry

The oyster shell was washed with distilled water and ethyl alcohol to remove impurities on the surface and dried in an oven at 100 ° C for 1 hour.

Dried oyster shells were crushed using a bowl and sieved to prepare oyster shell fine powders of 100 μm or less.

The oyster shell fine powder was calcined in an electric furnace at 1,000 DEG C for 2 hours and then pulverized with a mortar to obtain an oyster shell fine powder of 75 mu m or less.

Oyster shell slurry was prepared from the second pulverized oyster shell fine powder by using a wet ball mill method in a high density polyethylene (HDPE) vessel.

The wet ball mill was prepared by charging 10 g of the secondarily pulverized oyster shell powder and 500 g of distilled water into a container made of HDPE and then ball milling at 108 rpm for 2 hours using an alumina ball having a diameter of 25 nm to prepare an oyster shell slurry.

Example 2: Preparation of composition for removing green algae using oyster shell

The oyster shell slurry prepared in Example 1 and the amorphous starch were mixed in a weight ratio of 1: 4 to prepare a composition for removing green algae from waste water using oyster shells.

Comparative Example 1

The composition was prepared in the same manner as in Example 1 except that calcium oxide was used.

Comparative Example 2

The same procedure as in Example 1 was carried out except that dolomite dust powder was used to prepare a composition.

Experimental Example 1: Component analysis

Untreated oyster shells, burnt lime and dolomite powder were analyzed by X-ray fluorescence analysis to analyze the components of the oyster shell.

Table 1 below shows the results of X-ray fluorescence analysis of untreated oyster shell, burnt lime and dolomite dust powder.

Component analysis result SiO ₂ Al ₂ O ₃ FeO ₃ CaO MgO K ₂ O Na ₂ O TiO MnO P ₂ O ₅ Igloss quicklime 0.11 0.03 0.09 55.54 0.20 0.03 &Lt; 0.02 <0.01 0.01 0.01 43.79 dolomite 0.06 0.04 0.18 31.27 21.81 0.03 &Lt; 0.02 0.01 0.07 0.01 46.37 Oyster shell 0.45 0.12 0.06 53.66 0.26 0.06 0.55 <0.01 0.07 0.16 44.56

As shown in Table 1, the quicklime contains a large amount of CaO and a small amount of SiO ₂ and MgO, and dolomite showing the chemical composition of CaMg (CO ₃ ) ₂ contains Ca as well as Mg as a main component .

As a result of the analysis of the components, it was confirmed that oyster shell and lime were similar to each other and contained Ca at a high concentration. Since the oyster shell was identified as a chemical composition similar to that of quicklime, the reactivity with green algae, phosphorus, It can be confirmed that it will be similar.

Experimental Example 2: Reactive analysis

In order to confirm the reactivity of the calcined oyster shell in the solution, the hydration activity was measured over time and shown in Figs. 1 to 3. Fig.

2 to 4 are graphs showing hydration activity of quicklime, dolomite dust powder and calcined oyster shell.

Referring to Figs. 2 to 4, all three species show an exothermic reaction in which the temperature increases with time, but all three species show different hydration activity patterns.

The quicklime showed rapid hydration activity in a short time and was observed up to a maximum temperature of 70 ° C. The dolomite dust powder gradually increased to 600 ° C. and reached 48 ° C. The calcined oyster shell was very slow in hydration activity, The maximum temperature was not reached.

In conclusion, it can be seen that the quicklime and oyster shell have similar composition and particle size through the analysis of the components, but they show different hydration activity due to some other elements such as Si and Na in both samples.

Experimental Example 3: pH Analysis

In order to observe the pH change of the solution containing green algae, phosphorus and nitrogen, the amount of oyster shell slurry prepared according to Example 1 was variously added to a solution containing green algae, phosphorus and nitrogen.

In addition, dolomite dust powder produced according to Comparative Example 2 was used as a comparative example.

FIG. 5 shows the results of pH analysis according to the amount of the composition prepared according to Example 1 and Comparative Example 2. FIG.

Referring to FIG. 5, it can be seen that the pH increases as the amount of slurry prepared according to Example 1 and Comparative Example 2 increases.

The pH of the oyster shell slurry prepared in Example 1 was 5.0 g / L and the pH of the solution was 11.7, and the pH was steadily increased until 12.5 g / L of the slurry was added.

The reason why the pH is increased as the amount of the oyster shell slurry prepared in Example 1 is increased is that Ca (OH) ₂ contained in the slurry is present as Ca ²⁺ ions and OH ^- ions in the solution, Because the Ca ²⁺ ions contained in the surface react with the CO ₂ or CO ₃ ^2- ions contained in the surface of the green algae to react with the nitrogen and phosphorus ions present in the solution. This causes the pH to increase to 13 due to the increase of OH ^- ions.

When the pH of the solution into which the slurry prepared according to Comparative Example 2 was added and the oyster shell slurry prepared according to Example 1 were compared within the entire range, the solution in which the oyster shell slurry prepared according to Example 1 was added Can be explained for two reasons.

First, Mg (OH) ₂ contained in the slurry prepared according to Comparative Example 2 has a lower solubility than the oyster shell slurry Ca (OH) ₂ prepared according to Example 1, and thus exhibits a low OH ^- concentration in the solution, Value.

Also, based on Le Chatelier's principle, in a parallel reaction, if a change in the concentration of the reactant or product occurs, the reaction proceeds toward the reaction to maintain the parallel state.

According to this principle, Ca (OH) ₂ as well as Mg (OH) slurry of Comparative Example 2 consisting of ₂ is due to Ca (OH) ₂ has a higher solubility in Mg (OH) ₂ is Mg ²⁺ and OH ^- ionized The pH of the solution to which the slurry prepared according to Comparative Example 2 is added is lower than the pH of the solution to which the oyster shell slurry prepared according to Example 1 is added.

As a result, it was confirmed that the oyster shell slurry prepared according to Example 1 can promote a better solidification reaction than the slurry prepared according to Comparative Example 2.

Experimental Example 4: Turbidity Analysis

The amount of slurry was increased and analyzed with a water quality analyzer to investigate the turbidity of the slurry prepared according to Example 1 and Comparative Example 2.

FIG. 6 is an image showing the precipitation rate and turbidity, increasing the amount of the slurry prepared according to Example 1 and Comparative Example 2. FIG.

FIG. 7 is a graph showing an increase in the amount of slurry prepared according to Example 1 and Comparative Example 2 and an analysis of turbidity. FIG.

Referring to FIG. 7, it can be seen that as the amount of the slurry prepared according to Example 1 and Comparative Example 2 is increased, the turbidity is decreased as the amount of slurry added increases. This indicates that the slurry and the green tide are removed by agglomeration reaction.

Embodiment turbidity when added to the oyster shell slurry 5g / L prepared according to Example 1 Comparative Example 2 confirmed that a turbidity less than the slurry prepared in accordance with, and this Ca (OH) ₂ is less soluble Mg (OH in more solution ) ₂ is contained in Comparative Example 2, which is consistent with the result of measuring the pH. In other words, it can be confirmed that Mg ²⁺ ion supply should be minimized in order to effectively agglomerate green algae.

Experimental Example 5: UV-VIS absorption spectrum analysis

The UV-VIS absorption spectrum was analyzed to analyze the microbial characteristics of the green algae solution added with the oyster shell slurry prepared according to Example 1.

The amount of oyster shell slurry prepared according to Example 1 was increased in the algae solution in the range of 250 nm to 700 nm using UV-VIS spectroscopy, and the microorganism characteristics of the algae solution were analyzed and shown in FIG.

8, in the case of the green algae solution not containing the slurry, the absorption peak was large at around 280 nm, and the absorption peak was continuously decreased when the amount of the slurry was increased to 7.5 g / L, and from 7.5 g / L to 12.5 g / L showed similar absorption intensity.

Therefore, it can be confirmed that the addition of 7.5 g / L of slurry to the algae solution is most effective for removal of microorganisms forming green algae.

Experimental Example 6: Reaction analysis of causal

The amount of slurry prepared according to Example 1 and Comparative Example 2 was increased, and the concentration of total phosphorus (TP) was measured after being added to the green algae solution.

9 is a graph showing the concentration of total phosphorus (TP) in the green algal solution according to the amount of the slurry prepared according to Example 1 and Comparative Example 2. FIG.

9, the total phosphorus (TP) decreased as the amount of slurry prepared according to Example 1 and Comparative Example 2 increased. In particular, the amount of oyster shell slurry produced according to Example 1 was 7.5 g / L The amount of total phosphorus (TP) is reduced rapidly, and phosphorus of all concentrations is removed. On the other hand, it was confirmed that the amount of the slurry prepared according to Comparative Example 2 did not affect the amount of 5 g / L, and the concentration of total phosphorus (TP) dropped rapidly after that. This indicates that the Ca ²⁺ ions are insufficient in the slurry prepared in accordance with Comparative Example 2 and can not bind all phosphorus in the solution.

Experimental Example 7: Structural Analysis

Fig. 10 shows an X-ray diffraction pattern of the oyster shell slurry produced according to Example 1. Fig.

FIG. 11 shows an X-ray diffraction pattern after the oyster shell slurry prepared according to Example 1 was reacted with the solution of the algae solution.

CaO, which is a major element of oyster shell, is wet - milled and is present as Ca (OH ^- ).

10 and 11, Ca ²⁺ ions in the oyster shell slurry produced according to Example 1 react with PO ₄ ^3- in the algal solution to form Ca ₃ (PO ₄ ) ₂ and Ca ₅ (PO ₄ ) ₃ OH And all the diffraction peaks for Ca (OH) ₂ after the reaction with the algae solution were not detected. However, a new peak of Ca ₅ (PO ₄ ) ₃ OH corresponding to hexagonal P63 / m at around 32 ° Respectively. In other words, it was confirmed that all Ca ions were precipitated by binding with phosphate ion (PO ₄ ^3- ).

On the other hand, as shown in FIGS. 10 and 11, calcite (CaCO ₃ ) can be formed by reacting with CO ₂ or CO ₃ ^{2- on the} surface of green algae in addition to formation of hydroxyapatite. As a result of X- The increase in the content in proportion to the amount of slurry can confirm that the Ca ²⁺ ion first reacts with PO ₄ ^3- before the reaction with CO ₂ or CO ₃ ^2- .

Experimental Example 7: Total phosphorus, total nitrogen and COD analysis

The total phosphorus (TP), total nitrogen and COD were analyzed by injecting Example 1, Example 2 and positive starch into the green algae solution.

Figures 12 and 13 show the increase in the amount of oyster shell slurry produced according to Example 1 and the measurement of COD and total phosphorus (TP), Figure 14 shows the increase in the amount of benign starch and the measurement of total nitrogen (TN) , Figs. 15 to 17 show the total phosphorus (TP), total nitrogen (TN) and COD measured by increasing the amount of the composition for removing green algae prepared according to Example 2. Fig.

The positive starch (g) Example 1 (g) Total input (g) Mixing ratio Green tea solution 0 0 0 sample 1 4 One 5 4: 1 sample 2 8 2 10 4: 1 sample 3 20 5 25 4: 1 sample 4 40 10 50 4: 1

Table 2 shows the mixing amount of Example 1 and the positive starch according to the mixing ratio of 4: 1.

Referring to Figures 12-17, it can be seen that a mixture of benign starch and oyster shell slurry can precipitate the green tide and remove total phosphorus and total nitrogen in the water system. In particular, when the amount of positive starch added was 4 g, the maximum amount of COD removal was shown. At 8 g, COD tended to increase, so that the positive starch dosage was 1 to 8 g most effective.

In addition, Example 1 showed that phosphorus was sufficiently removed even at 1 g / 200 ml, but since it seems to affect the sludge production amount, 1 to 2 g was the most effective.

The method for preparing a composition for removing green algae using the oyster shell according to the present invention has an advantage of being very effective in adsorbing and removing phosphorus, nitrogen and eutrophication substances contained in green tanks by using oyster shells.

In addition, when the oyster shell is used as a raw material according to the present invention, there is an advantage that the oyster shell which is left on the shore and causes pollution is reduced, so that coastal pollution can be reduced.

Although the present invention has been described in connection with the method for preparing the composition for removing green algae using the oyster shell according to an embodiment of the present invention, various modifications may be made without departing from the scope of the present invention.

Therefore, the scope of the present invention should not be construed as limited to the embodiments described, but should be determined by the scope of the appended claims, as well as the claims.

It is to be understood that the foregoing embodiments are illustrative and not restrictive in all respects and that the scope of the present invention is indicated by the appended claims rather than the foregoing description, It is intended that all changes and modifications derived from the equivalent concept be included within the scope of the present invention.

S100: washing the oyster shell
S200: step of drying oyster shell
S300: Step of calcining oyster shell
S400: Step of making oyster shell as slurry
S500: Step of mixing slurry and amphoteric starch

Claims (9)

(a) washing the oyster shell with distilled water and an organic solvent;
(b) drying the oyster shell of step (a);
(c) calcining the oyster shell of the step (b);
(d) preparing the oyster shell of step (c) as a slurry; And
(e) mixing the slurry of step (d) with the amorphous starch.
The method according to claim 1,
The organic solvent may include,
Ethyl alcohol. &Lt; RTI ID = 0.0 &gt; 11. &lt; / RTI &gt;
The method according to claim 1,
The step (c)
(C) a step of first crushing before the step (c)
And (ii) a second crushing step after the step (c).
The method according to claim 1,
The step (c)
Wherein the composition is carried out in an electric furnace at 800 to 1,200 DEG C for 1 to 4 hours.
The method according to claim 1,
The step (d)
Wherein the slurry is milled in a high-density polyethylene container to produce a slurry.
6. The method of claim 5,
Preferably,
And milling the mixture at 80 to 150 rpm for 30 to 180 minutes using alumina balls having a diameter of 20 to 30 mm.
The method according to claim 1,
The step (d)
Wherein the oyster shell of step (c) and distilled water are mixed at a weight ratio of 1:25 to 75 and milled.
The method according to claim 1,
The step (e)
Wherein the positive starch and the slurry of step (d) are mixed at a weight ratio of 1: 1 to 8: 1.
9. The method of claim 8,
The above-
Characterized in that the oyster shell is derived from at least one starch selected from the group consisting of corn starch, waxy corn starch, tapioca starch, potato starch, sweet potato starch, Sago starch, wheat starch, rice starch and high amylose starch. A method for producing a composition for removing green algae.

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