CN111065605A - Waste water treatment method - Google Patents
Waste water treatment method Download PDFInfo
- Publication number
- CN111065605A CN111065605A CN201880054414.9A CN201880054414A CN111065605A CN 111065605 A CN111065605 A CN 111065605A CN 201880054414 A CN201880054414 A CN 201880054414A CN 111065605 A CN111065605 A CN 111065605A
- Authority
- CN
- China
- Prior art keywords
- wastewater
- ilmenite
- treatment method
- nitrogen
- wastewater treatment
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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Classifications
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- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/52—Treatment of water, waste water, or sewage by flocculation or precipitation of suspended impurities
- C02F1/5236—Treatment of water, waste water, or sewage by flocculation or precipitation of suspended impurities using inorganic agents
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- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/52—Treatment of water, waste water, or sewage by flocculation or precipitation of suspended impurities
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/58—Treatment of water, waste water, or sewage by removing specified dissolved compounds
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/58—Treatment of water, waste water, or sewage by removing specified dissolved compounds
- C02F1/583—Treatment of water, waste water, or sewage by removing specified dissolved compounds by removing fluoride or fluorine compounds
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/58—Treatment of water, waste water, or sewage by removing specified dissolved compounds
- C02F1/586—Treatment of water, waste water, or sewage by removing specified dissolved compounds by removing ammoniacal nitrogen
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- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2103/00—Nature of the water, waste water, sewage or sludge to be treated
- C02F2103/34—Nature of the water, waste water, sewage or sludge to be treated from industrial activities not provided for in groups C02F2103/12 - C02F2103/32
- C02F2103/346—Nature of the water, waste water, sewage or sludge to be treated from industrial activities not provided for in groups C02F2103/12 - C02F2103/32 from semiconductor processing, e.g. waste water from polishing of wafers
Abstract
The invention relates to a wastewater treatment method, which comprises the following steps: step a, reacting waste water with ilmenite; and a step b of removing the metal complex generated in the step a. The wastewater treatment method of the present invention can remove nitrogen and fluorine components in wastewater simultaneously with excellent treatment efficiency using ilmenite, and is simple in overall process and industrially useful, and thus can be applied to various industrial fields.
Description
Technical Field
This application claims rights based on the priority of korean patent application No. 10-2017-0095375, 27/7/2017, and includes all the disclosure of the korean patent application as part of this specification.
The present invention relates to a wastewater treatment method.
Background
Industrial waste water containing nitrogen and fluorine components at high concentrations is produced in a large amount in various industrial fields such as the semiconductor and communication technology industry, the steel industry and steel processing industry, which are widely basic industrial materials, the fertilizer industry and the agricultural chemical manufacturing industry, which are closely related to agricultural product production, and the like, due to the characteristics of the processes.
The semiconductor industry is not only a key element of the information-oriented society and the development of advanced industries, but also a dominant industry in korea, and the amount of industrial wastewater discharged from the semiconductor industry is increasing year by year, and thus, effective treatment is urgently required.
In the manufacturing process of semiconductor elements, a large amount of nitric acid-based or hydrofluoric acid-based compounds are used for etching (etching) and cleaning (cleaning), and a large amount of water is used at the same time, and therefore, wastewater containing nitrogen and fluorine at high concentrations is discharged.
When a human body inhales fluorine at a concentration of 1.5ppm or more as an environmental standard value, not only bones but also nerves are damaged, and therefore, it is necessary to remove fluorine. Nitrogen is not only toxic to human bodies and other living bodies, but also causes eutrophication, causes water quality deterioration, is one of serious pollution sources, and is increasingly subjected to strict environmental restrictions.
The existing treatment methods for such industrial wastewater are roughly classified into physical, chemical and biological methods.
First, physical and chemical methods for treating the industrial wastewater include methods of removing the wastewater using an adsorbent, a precipitant, a catalyst, or by ion exchange, degassing, and electrolysis.
However, the conventional physical and chemical wastewater treatment methods have problems in that not only a large amount of adsorbents or precipitants are required to be used, or a composition of a specific environment is required, but also the apparatus is large and complicated, the treatment efficiency is low, and the economical efficiency is greatly deteriorated. In addition, there is a problem in the treatment of waste materials such as waste adsorbents, waste precipitants, and waste catalysts generated in the wastewater treatment.
On the other hand, as a biological industrial wastewater treatment method, that is, an existing biological method for treating the industrial wastewater, a Pasteur process (Bardenpho), A, has been developed2Wastewater treatment processes such as/O (Anaerobic/aerobic/Oxic), a/O (Anaerobic/Oxic), utc (university of Cape town), VIP (virginia. innovative Plant), and the like, which are mainly processes that operate by appropriately combining aeration (aeration) and non-aeration (non-aeration) and treat industrial wastewater by biological means such as microorganisms. Recently, such a biological treatment process is widely used in many developed countries.
However, this biological wastewater treatment process is suitable for removing nitrogen, and when it is required to treat industrial wastewater containing nitrogen at a high concentration, a long hydraulic retention time is required, and therefore, there are problems in that treatment efficiency and economy are greatly lowered, and it is difficult to manage microorganisms.
Therefore, research into a method for more efficiently and economically treating industrial wastewater containing nitrogen or fluorine components is actively being conducted.
For example, korean patent laid-open No. 10-1682392 discloses a wastewater treatment apparatus capable of removing nitrogen components from wastewater using oxygen and microorganisms requiring itch, and improving treatment efficiency by using a micro-bubble generating device to miniaturize the oxygen.
Further, korean laid-open patent No. 2016-0095452 discloses a method of removing fluorine components from wastewater using a composition comprising an Al compound, a ferric compound and an inorganic acid in a predetermined molar ratio.
These patents can remove only one of nitrogen and fluorine components from wastewater, and the effects thereof are insufficient. In addition, nitrogen and fluorine components cannot be removed simultaneously, and therefore, the treatment of industrial wastewater is not efficient enough. Therefore, there is a need for further research on a method for simultaneously treating nitrogen and fluorine components in industrial wastewater through a simple and efficient process.
Prior art documents
Patent document
(patent document 0001) Korean granted patent No. 10-1682392 (2016.11.29), wastewater treatment plant
(patent document 0002) korean laid-open patent No. 2016-0095452 (2016.08.11), a composition for removing fluorine components from wastewater and a method for removing fluorine components from wastewater using the same.
Disclosure of Invention
Technical problem
The present inventors have made various studies to solve the above problems, and as a result, they have confirmed that nitrogen and fluorine components can be efficiently removed at the same time by using ilmenite for wastewater treatment, and have completed the present invention.
Accordingly, an object of the present invention is to provide a wastewater treatment method capable of efficiently removing nitrogen and fluorine components contained in wastewater at the same time.
Technical scheme
In order to achieve the above object, the present invention provides a wastewater treatment method comprising: step a, reacting waste water with ilmenite; and a step b of removing the metal complex generated in the step a.
The ilmenite may be dosed to the wastewater at a concentration of 0.3g/L to 0.5 g/L.
The wastewater may comprise one or more selected from fluorine, ammonia nitrogen, and nitrate nitrogen.
The wastewater may be wastewater discharged in a semiconductor manufacturing process.
The step a can be carried out in a continuous manner or in a batch manner.
The step a may be performed at 40 ℃ to 80 ℃.
Advantageous effects
The wastewater treatment method of the present invention can simultaneously remove nitrogen and fluorine components by using ilmenite, thereby improving the wastewater treatment efficiency. In addition, nitrogen and fluorine components in wastewater can be effectively treated by a simplified process, and thus, the method is applicable to various industrial fields.
Detailed Description
The present invention will be described in more detail below.
The terms or words used in the specification and claims are not limited to conventional or dictionary meanings, and the inventor can appropriately define the concept of the term and describe his own invention in an optimum manner, based on which the term or words should be interpreted in a manner conforming to the meaning and concept of the technical idea of the present invention.
The invention provides a wastewater treatment method, which can simultaneously remove nitrogen and fluorine components in wastewater.
Wastewater containing nitrogen and fluorine components is mostly generated from semiconductor production plants, oil refineries, and fine chemical plants. The wastewater discharged from these industrial sites contains nitrogen and fluorine in high concentrations, which are harmful to human bodies and the environment, and thus, a treatment process for removing these components is necessary.
Conventional techniques for treating wastewater containing nitrogen and fluorine components are not industrially applicable in terms of efficiency and economy because of low removal efficiency, complicated process, or the need for a scale of a predetermined level or more. In particular, the physical, chemical treatment methods require excessive input of compounds such as adsorbents, precipitants, etc. for separating specific components, and after treating wastewater, there is a problem in that much time and cost are consumed for treatment and regeneration of waste. On the other hand, the biological treatment method has problems in that a large area and a high degree of operation technique for the apparatus are required, and the treatment efficiency is largely changed as the external conditions are changed. Further, the biological treatment method causes microorganisms to simultaneously take in nitrogen components and nutrient salts in the wastewater, and thus, is difficult to apply to industrial wastewater containing less nutrient salts.
In view of the above, the present invention provides a wastewater treatment method which simultaneously removes nitrogen and fluorine components in wastewater using ilmenite with high efficiency.
Specifically, the wastewater treatment method of the present invention comprises: step a, reacting waste water with ilmenite; and a step b of removing the metal complex generated in the step a.
The present invention will be described in more detail below in terms of the steps.
First, in step a, the wastewater is reacted with ilmenite.
In the present invention, the wastewater to be treated is wastewater discharged in a semiconductor manufacturing process, and contains hydrofluoric acid (HF), ammonia (NH)3) Ammonium fluoride (NH)4F) Nitric acid (HNO)3) And the like. The wastewater comprises fluorine, ammonia Nitrogen (NH)3-N) and nitrate Nitrogen (NO)3-N) is selected.
The Ilmenite is a natural oxidized mineral of iron and titanium, called titanomagnetite (Ilmenite) or Ilmenite, with FeTiO3The chemical structural formula of (1). The ilmenite is used as titanium dioxide (TiO)2) The origin of the raw materials for commercial production of (1) is Australia, Norway, Russian Ural region, India, Canada, USA, Malaysia, etc., and the chemical composition varies depending on the origin. As an example, the FeTiO compound is also present3Fe (b) of2+Is replaced by Mg2+. In this case, the form of the ilmenite is not particularly limited, but a powder state is preferably used from the viewpoint of wastewater treatment efficiency, ease of handling, and the like. When used in the powder state, the ilmenite has an average particle size of 1000 μm or less, preferably 100 to 800 μm, more preferably 100 to 500 μm.
In step a of the present invention, nitrogen and fluorine components in the wastewater are reacted with the ilmenite to form, for example, a titanium compound ((NH)3)3TiF7) Iron compound ((NH)3)3FeF6) And the metal complex, thereby being removed.
In carrying out the reaction of the step a, the ilmenite may be charged in consideration of the concentrations of nitrogen and fluorine components in the wastewater to be treated. As an example, the ilmenite may be fed into the wastewater at a concentration of 0.3g/L to 0.5 g/L. When the amount of ilmenite to be charged is less than the above range, nitrogen and fluorine components in the wastewater cannot be sufficiently removed, and conversely, when it is more than the above range, there is no effect of improvement based on excessive charging, and thus it is uneconomical.
The step a reaction may be carried out at a temperature of 40 ℃ to 80 ℃. The reaction pressure may vary depending on the reaction conditions, and is not particularly limited, and can be selected from among reduced pressure, normal pressure, and increased pressure.
The step a can be carried out in a continuous manner or in a batch manner. The kind, form, size, etc. of the reactor are not limited as much as possible, and those skilled in the art can appropriately select them according to the composition, amount, reaction conditions of the wastewater to be treated.
According to an embodiment of the present invention, when the step a is performed in a continuous manner, the wastewater to be treated can be continuously passed through a filter or column packed with the ilmenite, thereby removing nitrogen and fluorine components in the wastewater.
In one embodiment of the invention, the wastewater is passed at a prescribed flow rate to be sufficiently contacted with ilmenite, in which case the flow rate of the wastewater may be 10 to 1000 ml/min.
According to another embodiment of the present invention, when the step a is performed in a batch manner, ilmenite can be charged into a reactor including the wastewater and stirred, thereby removing nitrogen and fluorine components in the wastewater.
In the stirring, the stirring time and the stirring speed may be adjusted so that the wastewater is brought into sufficient physical contact with the ilmenite, and the stirring may be performed at 100 to 300rpm for 60 to 90 minutes, for example
Next, in step b, the metal complex generated in the above step a is removed.
The metal complex is a titanium compound or an iron compound formed by the step a.
The removal can be carried out in such a way that the metal complex formed precipitates. As an example, the precipitation can be performed under conditions of 40 ℃ to 80 ℃ (or pH 6 to 9).
The wastewater from which the metal complex is removed can be discharged as treated water.
Further, after said step b, a flocculating agent can be added.
The flocculant is used for removing nitrogen and fluorine components remaining in the wastewater subjected to the steps a and b, and is not particularly limited as long as it is commonly used in the art. As an example, the flocculant may be an inorganic flocculant or an organic flocculant.
For example, the inorganic flocculant may be calcium hydroxide (Ca (OH)2) Calcium chloride (CaCl)2) Calcium oxide (CaO), calcium sulfate (CaSO)4) Calcium carbonate (CaCO)3) Poly aluminum Chloride (Poly aluminum Chloride; PAC), ferrous chloride (FeCl)2) Iron chloride (FeCl)3) Aluminum sulfate (Al)2(SO4)3) Ferrous sulfate (FeSO)4) Iron (Fe) sulfate2SO4) Ammonium alum (Al (NH)4)(SO4)2·12H2O), Sodium Aluminate (Sodium Aluminate), and the like. The organic flocculant may be a polyacrylamide-based polymer.
The wastewater treatment method of the present invention has the following advantages compared with the existing wastewater treatment methods.
First, the use of ilmenite enables simultaneous removal of nitrogen and fluorine components in wastewater, and is excellent in process efficiency and economic efficiency because of its excellent treatment efficiency.
Second, the wastewater treatment method of the present invention can achieve excellent treatment efficiency through simplified processes, and thus can be applied to various industrial fields.
Therefore, according to the present invention, the removal efficiency of nitrogen and fluorine components in wastewater is 90%, preferably 95% or more, respectively. The treated water finally discharged by the wastewater treatment method of the present invention has a nitrogen concentration of 30ppm or less and a fluorine concentration of 10ppm or less.
The present invention will be described in more detail below with reference to examples. It is understood by those skilled in the art that these examples are merely for more specifically illustrating the present invention, and the scope of the present invention is not limited to these examples, in accordance with the gist of the present invention.
Examples and comparative examples
Example 1
The wastewater was passed through an ilmenite filter at a flow rate of 10ml/min at 50 ℃ for 60 minutes.
After the wastewater passed through the filter was allowed to settle for 90 minutes, the precipitate was removed to obtain treated water.
Example 2
After 500mg of ilmenite were charged into 1000ml of wastewater, it was stirred at 300rpm for 90 minutes at 80 ℃.
After the completion of the stirring, the wastewater was allowed to settle for 90 minutes, and then the precipitate was removed, thereby obtaining treated water.
Comparative example 1
500mg of calcium hydroxide (Aldrich, 10 to 100 μm) was added to 1000ml of wastewater, and the mixture was stirred at 300rpm for 90 minutes at 60 ℃.
After the completion of the stirring, the wastewater was allowed to settle for 90 minutes, and then the precipitate was removed, thereby obtaining treated water.
Experimental example 1: analysis of treated Water
The concentrations of nitrogen and fluorine in the wastewater and the treated water used in the examples and comparative examples were measured.
The nitrogen concentration was measured by the nano-meter (Nessler) method in the Hash Manual (HACH manual).
The fluorine concentration is measured on the basis of standardized Methods (Standard Methods, APHA, 1995) and C-MAC company manual (manual).
At this time, the results obtained are shown in table 1 below.
TABLE 1
It was confirmed that the examples of the present invention more effectively remove nitrogen and fluorine components in wastewater than comparative example 1 using the conventional wastewater treatment method.
Industrial applicability
The wastewater treatment method of the present invention can remove nitrogen and fluorine components in wastewater simultaneously with excellent treatment efficiency by using ilmenite, and can be applied to various industries.
Claims (7)
1. A wastewater treatment method is characterized by comprising the following steps:
step a, reacting waste water with ilmenite; and
and b, removing the metal complex generated in the step a.
2. The wastewater treatment method according to claim 1,
the ilmenite was dosed into the wastewater at a concentration of 0.3 to 0.5 g/L.
3. The wastewater treatment method according to claim 1,
the wastewater contains one or more selected from fluorine, ammonia nitrogen and nitrate nitrogen.
4. The wastewater treatment method according to claim 1,
the wastewater is wastewater discharged in a semiconductor manufacturing process.
5. The wastewater treatment method according to claim 1,
said step a of reacting the waste water with ilmenite is carried out in a continuous manner.
6. The wastewater treatment method according to claim 1,
said step a of reacting the waste water with ilmenite is carried out in a batch mode.
7. The wastewater treatment method according to claim 1,
said step a of reacting the waste water with ilmenite is carried out at 40 ℃ to 80 ℃.
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| KR10-2017-0095375 | 2017-07-27 | ||
| KR1020170095375A KR102099426B1 (en) | 2017-07-27 | 2017-07-27 | Method for treating industrial wastewaters |
| PCT/KR2018/006660 WO2019022376A1 (en) | 2017-07-27 | 2018-06-12 | Wastewater treatment method |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN111065605A true CN111065605A (en) | 2020-04-24 |
Family
ID=65040259
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201880054414.9A Pending CN111065605A (en) | 2017-07-27 | 2018-06-12 | Waste water treatment method |
Country Status (3)
| Country | Link |
|---|---|
| KR (1) | KR102099426B1 (en) |
| CN (1) | CN111065605A (en) |
| WO (1) | WO2019022376A1 (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116282699B (en) * | 2023-03-06 | 2023-12-05 | 武汉天源环保股份有限公司 | Semiconductor wastewater treatment method and system |
Family Cites Families (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH09117775A (en) * | 1995-10-23 | 1997-05-06 | Shinriyou:Kk | Treatment of waste liquid containing fluorine and ammonia nitrogen |
| JP3688505B2 (en) * | 1999-03-18 | 2005-08-31 | 富士通株式会社 | Method and apparatus for treating fluorine-containing waste liquid |
| JP2001300518A (en) * | 2000-04-19 | 2001-10-30 | Nippon Shokubai Co Ltd | Treatment method of ammonia-containing waste water |
| JP2003285083A (en) * | 2002-03-27 | 2003-10-07 | Tsukishima Kikai Co Ltd | Cleaning method for water |
| KR100596666B1 (en) * | 2004-03-02 | 2006-07-06 | 주식회사 바이오플러스 | Method for treating waste water |
| US7553418B2 (en) * | 2007-08-18 | 2009-06-30 | Khudenko Engineering, Inc. | Method for water filtration |
| JP5422525B2 (en) * | 2010-09-03 | 2014-02-19 | 株式会社東芝 | Wastewater treatment method |
| WO2014018419A1 (en) * | 2012-07-21 | 2014-01-30 | K-Technologies, Inc. | Processes for the recovery of fluoride and silica products and phosphoric acid from wet-process phosphoric acid facilities and contaminated waste waters |
| KR101656825B1 (en) | 2015-02-03 | 2016-09-12 | 최윤진 | Composition for removing fluorine component from waste water and method of removing fluorine component from waste water |
| KR101682392B1 (en) | 2016-04-19 | 2016-12-05 | 정재억 | Wastewater disposal equipment |
-
2017
- 2017-07-27 KR KR1020170095375A patent/KR102099426B1/en active IP Right Grant
-
2018
- 2018-06-12 CN CN201880054414.9A patent/CN111065605A/en active Pending
- 2018-06-12 WO PCT/KR2018/006660 patent/WO2019022376A1/en active Application Filing
Also Published As
| Publication number | Publication date |
|---|---|
| WO2019022376A1 (en) | 2019-01-31 |
| KR20190012432A (en) | 2019-02-11 |
| KR102099426B1 (en) | 2020-04-09 |
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