KR20140081952A - Adsorbent of organic compounds in waste water by using coal fly ash and preparation method thereof - Google Patents

Adsorbent of organic compounds in waste water by using coal fly ash and preparation method thereof Download PDF

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Publication number
KR20140081952A
KR20140081952A KR1020120150157A KR20120150157A KR20140081952A KR 20140081952 A KR20140081952 A KR 20140081952A KR 1020120150157 A KR1020120150157 A KR 1020120150157A KR 20120150157 A KR20120150157 A KR 20120150157A KR 20140081952 A KR20140081952 A KR 20140081952A
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South Korea
Prior art keywords
adsorbent
organic substance
acid
coal ash
solution
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KR1020120150157A
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Korean (ko)
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김병억
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재단법인 포항산업과학연구원
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Priority to KR1020120150157A priority Critical patent/KR20140081952A/en
Publication of KR20140081952A publication Critical patent/KR20140081952A/en

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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
    • B01D53/02—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols by adsorption, e.g. preparative gas chromatography
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J20/00—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof
    • B01J20/02—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof comprising inorganic material
    • B01J20/20—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof comprising inorganic material comprising free carbon; comprising carbon obtained by carbonising processes
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J20/00—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof
    • B01J20/28—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof characterised by their form or physical properties
    • B01J20/28054—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof characterised by their form or physical properties characterised by their surface properties or porosity
    • B01J20/28057—Surface area, e.g. B.E.T specific surface area
    • B01J20/28061—Surface area, e.g. B.E.T specific surface area being in the range 100-500 m2/g
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J20/00—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof
    • B01J20/30—Processes for preparing, regenerating, or reactivating

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  • Chemical & Material Sciences (AREA)
  • Analytical Chemistry (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Organic Chemistry (AREA)
  • Inorganic Chemistry (AREA)
  • Engineering & Computer Science (AREA)
  • General Chemical & Material Sciences (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
  • Water Treatment By Sorption (AREA)
  • Solid-Sorbent Or Filter-Aiding Compositions (AREA)

Abstract

The present invention relates to an adsorbent for organic substances from waste water using coal fly ash and a preparation method thereof. More specifically, the present invention provides a preparation method including the steps of preparing fine coal particles, adding acid, and adding alkali and an adsorbent of organic substances by the preparation method. According to the present invention, an adsorbent of organic substances from waste water is prepared using coal fly ash which is a waste generated after coal combustion, thereby allowing a waste to be recycled as a resource. Also, the organic substances in waste water can be adsorbed and removed by a treatment using the adsorbent, and thus the adsorbent can also be used for purification of waste water.

Description

[0001] The present invention relates to an adsorbent for organic materials in wastewater using coal ash and a method for preparing the same,

The present invention relates to a method for producing an adsorbent having a capability of removing an organic substance contained in wastewater by chemically treating a coal fly ash, which is a waste generated after burning coal used as an energy source in a thermal power plant, .

At present, the domestic coal-fired power plant is a waste collected in the dust collector after coal is burned, and a large amount of coal ash is generated every year, and the disposal method is a problem.

The generated coal ash is left in the yard or buried in the yard. In this case, there is a high possibility of environmental pollution. In particular, coal ash contains harmful substances such as heavy metals and is difficult to be recycled.

In addition, for landfilling, additional chemical treatment and heat treatment are required, which is a costly waste. It is time to develop new applications through chemical treatment rather than landfill.

Table 1 below shows constituents of coal ash discharged from a thermal power plant.

ingredient Al 2 O 3 SiO 2 CaO Fe 2 O 3 MgO P 2 O 5 TiO 2 ZnO Na 2 O K 2 O Concentration (% by weight) 20.4 53.3 4.08 3.50 1.19 0.32 0.92 0.11 1.34 1.70 ingredient Al Fe Mn Ni Cu Ti V Concentration (% by weight) 2.84 1.92 0.014 0.007 0.004 0.14 0.009

As shown in Table 1 above, since coal ash contains SiO 2 and Al 2 O 3 having excellent adsorption performance in an amount of about 74% by weight, when the specific surface area is widened through chemical treatment, it has the potential to exhibit very excellent adsorptivity have.

Conventionally, a method of injecting activated carbon into a wastewater sedimentation tank has been widely used in order to adsorb and remove organic substances from wastewater, but commercially available activated carbon is very expensive and has a disadvantage in terms of economy.

Therefore, if such coal ash is used in the production of an organic adsorbent, not only can the waste concept of coal ash be recognized as a resource concept, but also there is an advantage that it can be used for environmental purification by adsorbing and removing organic matter from wastewater.

As described above, the present invention provides a method for producing an adsorbent having a capability of removing an organic substance contained in wastewater by chemically treating a coal ash produced after combustion of coal to increase the specific surface area.

According to an embodiment of the present invention, there is provided a method of preparing a coal fly ash, comprising the steps of: preparing a coal ash fine particle by drying and pulverizing the coal ash;

An acid adding step of adding an acid solution to the coal ash fine particles to obtain an acid mixed coal ash; And

And adding an alkali solution to the acid mixed coal ash to obtain a solution containing an organic substance adsorbent.

The preparation step may dry the coal ash by 10 to 20% by weight.

The particulate coal ash particles may have a particle size of 5 to 15 mu m.

The acid solution may be added so that the pH of the acid mixed coal ash is 2.0 or less.

The acid solution may be at least one member selected from the group consisting of hydrochloric acid (HCl), nitric acid (HNO 3 ), sulfuric acid (H 2 SO 4 ) and phosphoric acid (H 3 PO 4 ).

The alkali solution may be added so that the pH of the solution containing the organic substance adsorbent is 10.0 or more.

The alkali solution may be at least one selected from the group consisting of sodium hydroxide (NaOH), potassium hydroxide (KOH) and calcium hydroxide (Ca (OH) 2 ).

The acid solution and the alkali solution may be used in the pickling process of the steel process and discarded.

And then filtering the solution containing the organic substance adsorbent subsequently to the alkaline adding step to obtain an organic substance adsorbent.

And then drying the organic substance adsorbent at 120 to 200 ° C for 1 to 2 hours in the subsequent filtration step.

The drying step may further comprise a pulverizing step of pulverizing the subsequently dried organic substance adsorbent to a particle size of 5 to 15 mu m.

The organic material may be at least one selected from the group consisting of benzene, toluene and derivatives thereof.

According to another embodiment of the present invention, there is provided an adsorbent for organic materials in wastewater using coal ash produced by the above production method.

The organic material adsorbent may have a specific surface area of 100 to 200 m 2 / g.

The organic substance adsorbent may be treated with organic substances at a concentration of 1 to 50 g / L based on the amount of wastewater for 1 to 3 hours.

The present invention can recycle wastes as resources by producing an adsorbent that removes organic substances in wastewater by using coal as a waste generated after combustion of coal, and by adsorbing organic materials of wastewater through the treatment of the adsorbent, So that it can be used for wastewater purification.

FIG. 1 is a graph showing changes in COD and BOD of wastewater after treating coal ash produced in Example 1 with wastewater according to Experimental Example 1. FIG.

Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings. However, the embodiments of the present invention can be modified into various other forms, and the scope of the present invention is not limited to the embodiments described below.

According to an embodiment of the present invention, there is provided a method of manufacturing an organic substance adsorbent in wastewater using coal ash, which will be described in detail below.

The present invention relates to a method for preparing a coal ash-containing coal ash, comprising the steps of preparing a fine coal ash after drying and pulverizing the coal ash, adding an acid solution to the coal ash fine particles to obtain an acid mixed coal ash, A method for producing an organic substance adsorbent in a wastewater using coal ash comprising an alkaline adding step for obtaining a solution containing an adsorbent.

In the preparation step of the present invention, coal as a waste obtained after combustion of coal may be dried to have a water content of 10 to 20% by weight and then pulverized to obtain fine coal ash particles having a particle size of 5 to 15 탆.

When the water content of the coal ash exceeds 20% by weight, the efficiency of the acid treatment may be lowered.

If the particle size of the coal ash is less than 5 탆, it may be advantageous in terms of modification but economical because it is costly. If the particle size exceeds 15 탆, too much time may be required for surface modification.

In the acid addition step of the present invention, an acid solution may be mixed with the fine coal particles obtained in the preparation step to obtain an acid mixed coal ash. At this time, the acid solution should be added so that the pH of the acid-mixed coal ash is 2.0 or less so that various metallic components contained as impurities in the coal ash can be dissolved or removed to activate the coal ash surface.

The acid solution may be at least one selected from the group consisting of hydrochloric acid (HCl), nitric acid (HNO 3 ), sulfuric acid (H 2 SO 4 ) and phosphoric acid (H 3 PO 4 ) Do.

In the alkali addition step of the present invention, an alkali solution may be added to the acid mixed coal material obtained in the acid addition step to obtain a solution containing the organic material adsorbent. At this time, the alkaline solution should be added so that the pH of the organic substance adsorbent is 10.0 or more so that the specific surface area of silica (SiO 2 ) present in the coal ash is physically increased, and the organic substance adsorption site can be increased.

The alkali solution may be at least one kind selected from the group consisting of sodium hydroxide (NaOH), potassium hydroxide (KOH) and calcium hydroxide (Ca (OH) 2 ), and sodium hydroxide is most preferably used.

The acid solution and the alkali solution used in the present invention can be used as a by-product after the pickling process in the steel making process and can be discarded, which is very economical and environmentally advantageous.

The present invention may further comprise a filtration step of filtering the solution containing the organic substance adsorbent subsequently to the alkaline addition step to obtain an organic substance adsorbent. At this time, the type of the filter is not particularly limited, and it is preferable that the pore size is less than 5 탆.

The present invention may further comprise a drying step in which the organic substance adsorbent is subsequently dried at 120 to 200 ° C for 1 to 2 hours in the filtration step. If the drying temperature is lower than 120 ° C, water evaporation may not be performed properly. If the drying temperature exceeds 200 ° C, the specific surface area may be reduced.

The drying step may be carried out using an oven, but not limited thereto, and may be performed by irradiation with electromagnetic waves or infrared rays.

Further, the present invention may further comprise a pulverizing step of pulverizing the subsequently dried organic material adsorbent to a particle size of 5 to 15 탆 in the drying step.

The organic material which can be adsorbed and removed by using the organic material adsorbent of the present invention is preferably at least one selected from the group consisting of benzene, toluene and derivatives thereof, But is not limited thereto.

According to another embodiment of the present invention, there is provided an adsorbent for organic material in wastewater using coal ash produced by the above production method.

Since the coal ash has a specific surface area of about 10 to 15 m 2 / g, which is much lower than the activated carbon having a specific surface area of 200 m 2 / g or more, it is necessary to secure the contact area with the organic material sufficiently and to increase the specific surface area very important.

The specific surface area of the organic substance adsorbent of the present invention may be increased by chemical treatment of the particulate coal ash, and the specific surface area of the organic substance adsorbent may be 100 to 200 m 2 / g.

The organic material adsorbent of the present invention is characterized in that the organic material to be adsorbed is added at a concentration of 1 to 50 g / L, 1 To < / RTI > 3 hours. If the treatment time is less than 1 hour, the organic matter adsorption rate is reduced. If the treatment time exceeds 3 hours, there is no increase in the adsorption rate, and as the treatment time becomes longer, the total adsorption rate may decrease.

Example

Hereinafter, the present invention will be described more specifically by way of specific examples. The following examples are provided to aid understanding of the present invention, and the scope of the present invention is not limited thereto.

[Example 1]

100 ml of 2 N hydrochloric acid was added to 10 g of coal ash having an average particle size of 10 탆 and stirred for 6 hours. When the hydrochloric acid used is waste hydrochloric acid, hydrochloric acid is added until the pH is maintained at 1 or less. After the stirring, the pH was adjusted to 12 by addition of caustic soda solution and the mixture was stirred at 90 ° C for 12 hours. The resulting white precipitate was filtered with a filter paper and dried in an oven at 120 ° C. The specific surface area of the organic substance adsorbent prepared by pulverizing the solidified solid after drying was measured to be 148 m 2 / g.

[Comparative Example 1]

Calcium hydroxide (Ca (OH) 2 ), which is widely used as a water treatment agent, was used as an organic substance adsorbent.

[Experimental Example 1]

The organic substance adsorbent prepared in Example 1 was put into an amount of 1 g / L, 5 g / L and 50 g / L in 200 ml of wastewater having a chemical oxygen demand (COD) of 96.1, stirred for 2 hours in a stirrer, And the results are shown in Fig. 1 (a).

The organic substance adsorbent prepared in Example 1 was added to 200 ml of wastewater having a biological oxygen demand (BOD) of 29.0 in an amount of 5 g / L and 50 g / L, L and stirred for 2 hours in an agitator, and the BOD was measured. The results are shown in FIG. 1 (b).

[Experimental Example 2]

In the BOD measurement, 200 ml of the wastewater having a biological oxygen demand (BOD) of 29.0 was stirred in an agitator for 2 hours and 12 hours, respectively, in an amount of 5 g / L each of the organic substance adsorbent prepared in Example 1, After stirring for 2 hours at the amount of 50 g / L of the adsorbent, the BOD was measured and the results are shown in FIG. 1 (b).

The organic substance adsorbent of Comparative Example 1 was added in an amount of 50 g / L and stirred for 2 hours in an agitator, and then BOD was measured. The results are also shown in FIG. 1 (b).

Referring to Experimental Example 1, it was confirmed that the COD of wastewater was reduced to 34 46% as shown in Fig. 1 (a). At this time, it was found that the COD reduction rate was the highest when the adsorbent of Example 1 was treated with 5 g / L, and it was found that the COD reduction rate was no longer improved when 50 g / L was used. Thus, it can be seen that the adsorbable organic material was adsorbed and removed at all when the adsorbent of Example 1 was treated at 5 g / L.

1 (b), it was confirmed that the BOD of the wastewater was reduced by 82 to 87% after the adsorbent treatment of Example 1, but it was confirmed that the BOD of the wastewater was decreased by 82 to 87% It was found that there was no significant difference in the BOD reduction rate of the agitation.

On the other hand, the slaked lime of Comparative Example 1, which is frequently used as a water treatment agent, showed a BOD reduction efficiency of about 47%, which is lower than that of the same amount of the adsorbent of Example 1.

Accordingly, it was confirmed that the organic substance adsorbent produced by the present invention adsorbs and removes organic substances in the wastewater, thereby lowering the COD and BOD of the wastewater, and is effective in purifying wastewater.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, but, on the contrary, It will be obvious to those of ordinary skill in the art.

Claims (15)

A preparation step of preparing coal ash particles by drying the pulverized coal and then pulverizing the pulverized coal;
An acid adding step of adding an acid solution to the coal ash fine particles to obtain an acid mixed coal ash; And
And adding an alkali solution to the acid mixed coal ash to obtain a solution containing an organic substance adsorbent.
The method as claimed in claim 1, wherein the preparation step comprises: Wherein the organic substance adsorbent is dried up to 20% by weight.
The method of claim 1, wherein the coal ash particles have a particle size of 5 to 15 탆.
The method of claim 1, wherein the acid solution is added so that the acid mixed coal ash has a pH of 2.0 or less.
The method according to claim 1, wherein the acid solution is at least one selected from the group consisting of hydrochloric acid (HCl), nitric acid (HNO 3 ), sulfuric acid (H 2 SO 4 ) and phosphoric acid (H 3 PO 4 ) A method for producing an adsorbent.
The method of claim 1, wherein the alkaline solution is added so that the pH of the solution containing the organic substance adsorbent is at least 10.0.
The method of claim 1, wherein the alkali solution is one selected from the group consisting of sodium hydroxide (NaOH), potassium hydroxide (KOH), and calcium hydroxide (Ca (OH) 2 ).
The method of claim 1, wherein the acid solution and the alkali solution are used in a pickling process of a steel process and are discarded.
The method of claim 1, further comprising a step of filtering the solution containing the organic substance adsorbent subsequently to the alkaline addition step to obtain an organic substance adsorbent.
The method of claim 9, further comprising a drying step of drying the organic substance adsorbent at 120 to 200 ° C for 1 to 3 hours subsequently to the filtration step.
[Claim 11] The method of claim 10, further comprising a pulverizing step of pulverizing the subsequently dried organic material adsorbent to a particle size of 5 to 15 mu m in the drying step.
The method of claim 1, wherein the organic material is at least one selected from the group consisting of benzene, toluene, and derivatives thereof.
An adsorbent for an organic substance produced by the method of any one of claims 1 to 12.
The organic substance adsorbent according to claim 13, wherein the organic substance adsorbent has a specific surface area of 100 to 200 m 2 / g.
The organic substance adsorbent according to claim 13, wherein the organic substance adsorbent is treated for 1 to 3 hours at a concentration of 1 to 50 g / L based on the amount of waste water in the organic substance.
KR1020120150157A 2012-12-21 2012-12-21 Adsorbent of organic compounds in waste water by using coal fly ash and preparation method thereof KR20140081952A (en)

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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR101661468B1 (en) * 2015-05-13 2016-09-30 주식회사 예솔랩 Absorbent of acid substances and heavy metal, and the preparation thereof
CN109502679A (en) * 2018-11-19 2019-03-22 山西大学 A kind of method that powdered coal ash multi-component element collaboration utilization prepares flocculant and porous material
KR20200016527A (en) * 2018-08-07 2020-02-17 인하대학교 산학협력단 Method for preparation of mesoporous silica form from power plant fly ash, and carbon dioxide sorbents or rare earth metals ion collector based on mesoporous silica form prepared by the method
CN114735736A (en) * 2022-03-28 2022-07-12 广西田东锦鑫化工有限公司 Method for removing various organic compounds in sodium aluminate solution in alumina production

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR101661468B1 (en) * 2015-05-13 2016-09-30 주식회사 예솔랩 Absorbent of acid substances and heavy metal, and the preparation thereof
WO2016182365A1 (en) * 2015-05-13 2016-11-17 주식회사 예솔랩 Agent for removing acidic materials and heavy metals and method for preparing same
KR20200016527A (en) * 2018-08-07 2020-02-17 인하대학교 산학협력단 Method for preparation of mesoporous silica form from power plant fly ash, and carbon dioxide sorbents or rare earth metals ion collector based on mesoporous silica form prepared by the method
CN109502679A (en) * 2018-11-19 2019-03-22 山西大学 A kind of method that powdered coal ash multi-component element collaboration utilization prepares flocculant and porous material
CN109502679B (en) * 2018-11-19 2021-12-31 山西大学 Method for preparing flocculating agent and porous material by synergistic utilization of multiple elements of fly ash
CN114735736A (en) * 2022-03-28 2022-07-12 广西田东锦鑫化工有限公司 Method for removing various organic compounds in sodium aluminate solution in alumina production
CN114735736B (en) * 2022-03-28 2024-05-03 广西田东锦鑫化工有限公司 Method for removing various organic compounds in sodium aluminate solution in alumina production

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