KR102037353B1 - Method for producing granular adsorbent for removing ionic pollutants using alum sludge and granular adsorbent produced thereby - Google Patents

Abstract

Disclosed are a method for preparing a granular adsorbent for removing harmful ions using alum sludge and a granular adsorbent prepared thereby. The method for preparing the adsorbent and the granular adsorbent prepared thereby form the adsorbent in granular form. Then, even if the adsorbent is applied to the site and used, the adsorbent does not agglomerate, and thus, the channeling phenomenon of the water may be prevented, and the flow path of the product in which the adsorbent is installed may be blocked. There can be. In addition, since the adsorbent is formed in the form of granules, it is possible to prevent the adsorbent from flowing out of the site of the product where the adsorbent is installed. Then, since there is no need for treating the spilled adsorbent, there may be a convenient effect.

Description

METHODS FOR PRODUCING GRANULAR ADSORBENT FOR REMOVING IONIC POLLUTANTS USING ALUM SLUDGE AND GRANULAR ADSORBENT PRODUCED THEREBY}

The present invention relates to a method for producing a granular adsorbent for removing toxic ions present in water using alum sludge and a granular adsorbent prepared thereby.

Harmful substances contained in drinking water are removed by various methods such as reverse osmosis, flocculation, oxidation, precipitation, electrodialysis or adsorption. In addition, the adsorption method is often used because it is simple, effective, and economical.

Alum is widely used for drinking water purification and is added as a coagulant to remove suspended and natural organic substances. When alum is added to water, amorphous aluminum hydroxide, which is a kind of alum sludge, can be produced. Since aluminum hydroxide is a porous material, it is used as a soil improver or a soil substitute.

As the amount of water used increases, the amount of alum used in the purification process also increases. Then, since a large amount of alum sludge is generated, a method for treating the alum sludge is also required.

As a result of much effort in developing a technology capable of treating alum sludge, the present applicants have obtained a patent (Registration No. 10-1344235) for "Adsorbent for removing toxic ions using alum sludge and its manufacturing method". .

The adsorbent disclosed in the registered patent No. 10-1344235 is in the form of a powder.

By the way, agglomeration phenomenon arises when a powder form adsorbent is applied and used on site.

Then, due to the aggregated adsorbents, a channeling phenomenon occurs, and a flow path of a product in which the adsorbent is installed is blocked.

In addition, since the adsorbent in the form of powder may flow out of the site of the product in which the adsorbent is installed, the flow rate may be limited or the adsorbent may be treated. Therefore, there is an uncomfortable problem.

An object of the present invention may be to provide a method for producing a granular adsorbent for removing harmful ions using alum sludge that can solve all the problems of the prior art as described above and the granular adsorbent prepared thereby.

Another object of the present invention is to prepare a granular adsorbent for removing toxic ions using alum sludge which can prevent the channeling phenomenon of water and the flow path of a product installed with the adsorbent by forming the adsorbent in the form of granules and thereby It may be to provide a granular adsorbent prepared.

Another object of the present invention is to prevent the outflow of the adsorbent outside the site of the product installed with the adsorbent, a method of producing a granular adsorbent for removing harmful ions using alum sludge which can be conveniently used and the granular adsorbent prepared thereby It may be to provide.

The method for producing a granular adsorbent according to the present invention is a method for producing an adsorbent for adsorbing and removing arsenic (As) ions, fluorine (F) ions, and selenium (Se) ions, including aluminum (Al) and manganese (Mn). And removing impurities of the Alum sludge containing iron (Fe), drying the pulverized alum sludge for 2 to 6 hours at 80 to 130 ° C., and then grinding the impurities. Calcining the pulverized alum sludge; Stirring the calcined alum sludge and binder into water; Hardening the stirred solution to form granules; The cured granules may be washed and dried.

In addition, the granular adsorbent according to the present invention, in the adsorbent manufacturing method for adsorbing and removing arsenic (As) ions, fluorine (F) ions and selenium (Se) ions, aluminum (Al), manganese (Mn) and Removing impurities of iron (Fe) -containing Alum Sludge, drying the alum sludge from which impurities have been removed at 80-130 ° C. for 2-6 hours, and then grinding; Calcining the pulverized alum sludge; Stirring the calcined alum sludge and binder into water; Hardening the stirred solution to form granules; The cured granules may be prepared through washing and drying.

A method for producing a granular adsorbent for removing toxic ions using an alum sludge and a granular adsorbent prepared therein are adsorbents formed in a granular form. Then, even if the adsorbent is applied to the site and used, the adsorbent does not agglomerate, and thus, the channeling phenomenon of the water may be prevented, and the flow path of the product in which the adsorbent is installed may be blocked. There can be.

In addition, since the adsorbent is formed in the form of granules, it is possible to prevent the adsorbent from flowing out of the site of the product where the adsorbent is installed. Then, since there is no need for treating the spilled adsorbent, there may be a convenient effect.

1 is a photograph showing a granular adsorbent prepared by a manufacturing method according to an embodiment of the present invention.
FIG. 2 is an enlarged photograph of a portion of FIG. 1;
Figure 3 is a flow chart showing a method for producing a granular adsorbent according to an embodiment of the present invention.
4A and 4B are graphs showing Langmuir Adsorption Iisotherm and Freundlich Adsorption Isotherm of the adsorbent.

The meaning of the terms described herein will be understood as follows.

Singular expressions should be understood to include plural expressions unless the context clearly indicates otherwise, and the terms “first”, “second”, etc. are used to distinguish one component from another. The scope of the rights shall not be limited by these terms.

It is to be understood that the term "comprises" or "having" does not preclude the existence or addition of one or more other features or numbers, steps, operations, components, parts or combinations thereof.

The term "at least one" should be understood to include all combinations which can be presented from one or more related items. For example, the meaning of "at least one of the first item, the second item, and the third item" means not only the first item, the second item, or the third item, but also two of the first item, the second item, and the third item. A combination of all items that can be presented from more than one.

The term “and / or” should be understood to include all combinations that can be presented from one or more related items. For example, the meaning of "first item, second item and / or third item" means two items of first item, second item or third item as well as first item, second item or third item. It means a combination of all items that can be presented from the above.

When a component is referred to as being "connected or installed" to another component, it is to be understood that other components may be present in the middle, although the components may be directly connected or installed. On the other hand, when a component is referred to as "directly connected or installed" to another component, it should be understood that there is no other component in between. On the other hand, other expressions describing the relationship between the components, that is, "between" and "immediately between" or "neighboring to" and "directly neighboring to", and the like, should be interpreted as well.

On the other hand, when a component is referred to as being “formed, coupled, and installed” with another component, the component and other components are separately provided, formed, combined, or installed, as well as with a component. It is to be construed as including any other component in one body.

In each step, an identification code (for example, S100, S110, S120, etc.) is used for convenience of description, and the identification code is not intended to describe the order of the steps, and each step is clearly specified in context. Unless stated in order, it may occur differently from the stated order. That is, each step may occur in the same order as specified, may be performed substantially simultaneously, or may be performed in the reverse order.

Hereinafter, a method for preparing a granular adsorbent for removing toxic ions using alum sludge according to an embodiment of the present invention and a granular adsorbent prepared thereby will be described in detail.

1 is a photograph showing a granular adsorbent prepared by a manufacturing method according to an embodiment of the present invention, Figure 2 is an enlarged photograph taken from a portion of FIG.

As shown, the adsorbent according to the embodiment of the present invention can be removed by adsorbing arsenic (As) which is a harmful substance contained in drinking water. The adsorbent according to the embodiment of the present invention may be formed into a granular form, and may be formed into a granular form using the adsorbent disclosed in the registered patent application No. 10-1344235 filed by the applicants. .

Since the adsorbent according to the embodiment of the present invention is manufactured using the adsorbent of the registered patent, it is natural that the content disclosed in the registered patent is included in the content of the present invention.

The adsorbent disclosed in the registered patent is prepared by using an Alum Sludge generated in the water treatment process.

In the water treatment process, alum (Al ₂ (SO ₄ ) _{3 ·} 14H ₂ O) is added to remove solids and organic substances to aggregate contaminants. The addition of alum to water produces amorphous Aluminum Hydroxide (Al (OH) ₃ ), which can be used as an adsorbent for hazardous substances.

The adsorbent disclosed in the patent publication removes the impurities of the alum sludge, dries the alum sludge from which the impurities are removed for 2 to 6 hours at 80 ° C. to 130 ° C., and then grinds the dried sludge to prepare a powder form. . At this time, the surface area of the adsorbent is 30m ² / g to 50m ² / g, the diameter is 50μm to 200μm.

The adsorbent disclosed in the above-mentioned patent publication has an adsorption amount of 8.89 mg / g or more for trivalent arsenic (As) and a maximum adsorption amount of 5.15 mg / g or more for pentavalent arsenic at room temperature. Therefore, the adsorption effect of arsenic is excellent.

In addition, the adsorbent disclosed in the above-mentioned patent publication is made most of the adsorption within 30 to 60 minutes. The hazardous ions adsorbed on the adsorbent can be easily desorbed and recycled.

In the water treatment process, various materials are added as well as alum. As a result, the alum sludge contains aluminum (Al), silicon (Si), titanium (Ti), vanadium (V), chromium (Cr), manganese (Mn), iron (Fe), copper (Cu), and zinc (Zn). , Zirconium (Zr), tin (Sn) and the like may be contained.

A method for preparing an adsorbent according to an embodiment of the present invention will be described with reference to FIG. 3. Figure 3 is a flow chart showing a method for producing a granular adsorbent according to an embodiment of the present invention.

As shown, in step S110 it is possible to obtain an Alum sludge (Slum) in the water treatment plant, the aluminum sludge (Al), silicon (Si), titanium (Ti), vanadium (V), chromium ( Cr), manganese (Mn), iron (Fe), copper (Cu), zinc (Zn), zirconium (Zr), tin (Sn), and the like.

At this time, the aluminum sludge may contain only aluminum (Al), manganese (Mn), and iron (Fe).

Thereafter, in step S120, impurities of the alum sludge may be removed, and in step S130, the alum sludge from which the impurities are removed may be dried at 80 ° C. to 130 ° C. for 2 to 6 hours, and then the surface area may be from 30 m ² / g to 50 m ² / g, it can be milled to a diameter of 50μm to 200μm.

Thereafter, in step S140, the pulverized alum sludge may be calcined. Applicants have found through experiments that the arsenic adsorption rate of the adsorbent according to this embodiment is high when the pulverized alum sludge is calcined at a predetermined temperature. Through the experimental results, in step S140, the pulverized alum sludge may be calcined at 290 ° C-310 ° C for 23-25 hours.

Thereafter, in step S150, the calcined alum sludge and the binder may be put in water and stirred. The binder is an additive for binding the alum sludge in powder form to form granules.

In the method for preparing an adsorbent according to an embodiment of the present invention, sodium alginate may be used as a binder, or sodium alginate and polyvinyl alcohol may be used as a binder.

Sodium alginate is a long polymer that is present in combination with sodium cations and is a series of molecules bonded together. Sodium alginate is insoluble in water, but the alkali salt of sodium alginate dissolves in water and has a very viscous solution.

And polyvinyl alcohol has the function of an adhesive agent.

In step S151, the calcined alum sludge and sodium alginate as a binder were added to water and stirred (S151), in which 5 to 15 g of alum sludge and 1 to 3 g of sodium alginate were added to 100 ml of water, and at least 1 hour at 45 ° C to 55 ° C. It can be stirred.

In addition, the step of stirring the calcined alum sludge and the binder sodium alginate and polyvinyl alcohol in water (S155) includes 5-15 g of alum sludge, 1-3 g of sodium alginate, and polyvinyl alcohol 1 per 100 ml of water. 3 g of the solution can be stirred at 45 ° C-55 ° C for at least 1 hour.

Thereafter, in step S160, the solution in which the alum sludge and the binder are stirred may be cured to form a granule. In detail, the agitated solution of the alum sludge and the binder is inhaled by using a syringe (Syringe) or the like, and then immersed by dropping it in 0.5M (Mole) calcium chloride (CaCl ₂ ) solution. The stirred solution is then immersed in a calcium chloride (CaCl ₂ ) solution in the form of droplets and cured, and preferably immersed and cured for 36 to 48 hours to maintain an appropriate hardness.

Thereafter, in step S170, the cured granules may be washed using distilled water, and in step S180, the granules may be dried at 24 ° C-26 ° C for at least 24 hours.

A granular adsorbent is then produced. At this time, the size of the granular adsorbent is preferably approximately 1-2 mm in diameter.

Experimental Example

The result of an isotherm experiment performed with an adsorbent prepared by a manufacturing method according to an embodiment of the present invention will be described.

)를 각각 5, 10, 20, 50, 100, 300, 500 및 800mg를 넣어서 16시간동안 실험을 진행하였다.In order to investigate the adsorption capacity of the adsorbent according to the concentration of arsenic, pentavalent arsenic

), 5, 10, 20, 50, 100, 300, 500 and 800mg each was conducted for 16 hours.

At this time, 0.2 g of an adsorbent (hereinafter referred to as "first adsorbent") according to an embodiment of the present invention, wherein the binder is sodium alginate, was placed in 40 ml of arsenic solution for each concentration in which pentavalent arsenic was dissolved, and the binder was sodium alginate. 0.2 g of an adsorbent (hereinafter referred to as "second adsorbent") according to an embodiment of the present invention, which is a polyvinyl alcohol and polyvinyl alcohol, were put in 40 ml of arsenic solution for each concentration in which hexavalent arsenic was dissolved. 0.2 g of the disclosed adsorbent (hereinafter referred to as "registered adsorbent") was put into 40 ml of arsenic solution of each concentration in which hexavalent arsenic was dissolved, and Bayoxide (hereinafter, referred to as "a conventional adsorbent") which is a commercially available adsorbent. 0.2 g was added to 40 ml of arsenic solution for each concentration in which valent arsenic was dissolved.

Each solution was stirred at 30 rpm with an overhead shaker at 25 ° C., and then the solution was analyzed using ICP-OES (Agilent 7200, USA).

As a result, as can be seen in Figure 4 (a) and (b) and Table 1, judging the first adsorbent and the second adsorbent according to an embodiment of the present invention as the value of the correlation coefficient r ² , The first adsorbent was found to follow Langmuir Isotherm further, and the second adsorbent was found to follow both Langmuir Isotherm and Freundlich Isotherm.

In addition, in the maximum adsorption capacity (q _max ), the first adsorbent was similar to the conventional adsorbent, and the second adsorbent was superior to the conventional adsorbent.

division
Langmuir Isotherm Freundlich Isotherm q _max (mg / g) K _L (L / mg) r ² K _F (mol / gxL) n r ² First adsorbent 16.419 0.030 0.965 2.537 3.416 0.871 Second adsorbent 20.901 0.016 0.977 2.117 2.829 0.977 Registered adsorbent 33.013 1.042 0.957 10.935 5.192 0.915 Conventional Adsorbent 16.106 0.017 0.964 2.086 3.208 0.962

The granular adsorbent prepared by the manufacturing method according to the embodiment of the present invention may be removed by adsorbing not only arsenic (As) ions, but also fluorine (F) ions and selenium (Se) ions. In addition, the results of the isotherm experiment on fluorine (F) ions and selenium (Se) ions were similar to the results of the isotherm on arsenic ions.

Method for producing a granular adsorbent for removing harmful ions using alum sludge according to an embodiment of the present invention and the granular adsorbent prepared thereby form the adsorbent in granular form. Then, even when the adsorbent is applied to the site and used, the adsorbent does not agglomerate, and thus, a channeling phenomenon of the water may be prevented and the flow path of the product in which the adsorbent is installed may be blocked.

In addition, since the adsorbent is formed in the form of granules, it is possible to prevent the adsorbent from flowing out of the site of the product where the adsorbent is installed. This is convenient because no work is needed to treat the spilled adsorbent.

The present invention described above is not limited to the above-described embodiments and the accompanying drawings, and it is common in the art that various substitutions, modifications, and changes can be made without departing from the technical spirit of the present invention. It will be evident to those who have knowledge of. Therefore, the scope of the present invention is represented by the following claims, and it should be construed that all changes or modifications derived from the meaning and scope of the claims and equivalent concepts thereof are included in the scope of the present invention.

Claims (9)

In the manufacturing method of the adsorbent for adsorbing and removing arsenic (As) ions, fluorine (F) ions and selenium (Se) ions,
Remove impurities from Alum sludge containing aluminum (Al), manganese (Mn) and iron (Fe), and dry the alum sludge from which impurities are removed at 80-130 ° C. for 2-6 hours and then crush Doing;
Calcining the pulverized alum sludge;
Stirring the calcined alum sludge and binder into water;
Hardening the stirred solution to form granules;
Washing and drying the cured granules to produce a granular adsorbent;
The calcining of the pulverized alum sludge is calcined for 23-25 hours at 290-310 ° C to increase the arsenic adsorption rate of the granular adsorbent,
The binder is a method for producing a granular adsorbent, characterized in that sodium alginate (Sodium Alginate) and polyvinyl alcohol (Polyvinyl Alcohol). delete delete delete delete The method of claim 1,
5 to 15 g of the alum sludge, 1 to 3 g of the sodium alginate, and 1 to 3 g of the polyvinyl alcohol are added to 100 ml of water, and the mixture is stirred for 1 hour or longer at 45 to 55 ° C. Way. The method of claim 1,
The stirred solution is immersed in a drop of 0.1-0.5M (Mole) solution of calcium chloride (CaCl ₂ ) solution for 36 to 48 hours to cure the granular adsorbent. The method of claim 1,
Washing the cured granules with distilled water, the method of producing a granular adsorbent, characterized in that the drying for 24 hours or more at 24-26 ℃. A granular adsorbent prepared by the method according to any one of claims 1, 6, 7, and 8.

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