KR20100003528A - Non-degradable waste water treatment apparatus using electrolysis and photo-fenton oxidation process - Google Patents

Abstract

PURPOSE: An apparatus for treating non-degradable water using a complex acid chemical oxidation process with a photo-fenton oxidation process and a method thereof are provided to reduce the used quantity of second valent iron catalysts necessary for the photo-fenton oxidation process or a fenton oxidation process, and to reduce the consumption of hydrogen peroxide. CONSTITUTION: An apparatus for treating non-degradable water using a complex acid chemical oxidation process with a photo-fenton oxidation process includes a waste water storage(10), an electrolyte input device(20), an air supplier(30), a non-membrane cell(40), a UV photoreactor(50), and a water collector(60). The non-membrane cell has a plurality of cathodes(41) and a plurality of anodes(42) alternatively. The apparatus for treating non-degradable water further includes a line mixer(70), a circulation pump(80), a venture mixer(90), a porous diffuser(43), a transfer line(100), a pH neutralization chemical injector(110), and a flocculent settling basing(120).

Description

Non-degradable Waste Water Treatment Apparatus using Electrolysis and Photo-fenton Oxidation Process using Complex Oxidation Process Combined with Electrolysis and Photo-Fenton Oxidation Process

The present invention relates to a method for producing chlorine dioxide oxidized water using a membrane-free electrolytic cell that generates chlorine dioxide by electrolysis into a membrane-free electrolytic cell using a solution in which sodium chlorate (NaClO ₂ ) and sodium chloride (NaCl) are mixed.

Hardly degradable industrial wastewater generated by various industries is difficult to be treated by general biological treatment processes, and is mainly treated by chemical treatment processes or advanced oxidation processes due to the generation of a large amount of microbial sludge and the necessity of large facility sites. In particular, advanced oxidation process that completely oxidizes organic matter into CO ₂ and H ₂ O using powerful oxidation radical (OH) with high oxidation potential of 2.08 V next to fluorine. Advanced oxidation processes (AOPs) are known as representative hard-degradable industrial wastewater treatment technologies. Fenton oxidation or photo-fenton oxidation, which is the most commonly applied among these advanced oxidation processes, is a UV to Fenton oxidation process having a radical generation path as shown in [Scheme 1]. By combining the processes, it is possible to effectively enhance the generation of hydroxyl radicals (Hydrogen radicals) as shown in [Scheme 2], and to the bivalent ferrous salts and hydrogen peroxide (H ₂ O ₂ ) used as oxidants. There is an advantage to reduce the amount. However, in order to decompose organic substances in high concentration, there is a problem of using excess hydrogen peroxide oxidant due to continuous input of hydrogen peroxide and iron salt and sludge generation due to used iron salt. In recent years, by combining the Fenton oxidation process, the reduction tank with the electrode and the reaction tank, the trivalent iron (Fe ³⁺ ) generated during the Fenton oxidation process is electrochemically reduced to the divalent iron (Fe ²⁺ ) as shown in [Scheme 3]. Electrochemical Fenton oxidation process technology to improve the oxidation process efficiency, reduce the amount of iron salt used in the Fenton process and the sludge generated by this is being studied.

Scheme 1

^{_{Fe 2 + + H 2 O 2}} → Fe 3 + + OH - + · OH (1)

Fe ^{3 +} + H ₂ O ₂ → Fe ^{2 +} + H ⁺ + O ₂ H (2)

Scheme 2

H ₂ O ₂ + hv → 2 OH (3)

Fe (OH) ²⁺ → Fe ^{3 +} + OH (4)

^{_{Fe 2 + + H 2 O 2}} → Fe 3 + + OH - + · OH (5)

Scheme 3

Fe ^{3 +} + e- → Fe ^{2 +} , E ₀ = 0.77V (6)

In general, the phenton oxidation process generates hydrogen radicals by using hydrogen peroxide (H ₂ O ₂ ) and divalent iron salts (FeSO ₄ , FeCl ₂ etc.) as oxidants to convert organic compounds in water to CO _2. And oxidative decomposition with H ₂ O. In the Fenton oxidation process, hydrogen peroxide and divalent iron salt injected at a constant ratio react with each other to generate hydroxide radicals necessary for decomposition of organic matter, and the trivalent iron salt is oxidized to trivalent and trivalent iron salt as shown in Equation (1) in [Scheme 1]. Reacts with hydrogen peroxide as shown in Equation (2) in [Reaction Scheme 1] is reduced to a divalent iron salt to generate radicals by a continuous circulation process as shown in Equation (1) in [Reaction Scheme 1]. Therefore, hydrogen peroxide, which should be used to generate hydroxylated radicals by reaction with ferric iron, is also used to reduce trivalent iron to ferric iron, so that excess hydrogen peroxide is used, and the trivalent ferric reduction reaction is not a problem. have. Therefore, in the "electrolytic reduction fenton oxidation wastewater treatment device" of Korean Patent No. 0592942, domestic patent application 10-2001-0001766 "Wastewater treatment method using electrolysis" by combining the electrolysis device and the fenton oxidation process effectively reduce the iron catalyst Patents relating to the device and method for the purpose of improving the decomposition efficiency of organic matter has been previously filed. However, these patents have the disadvantage of using hydrogen peroxide.

The present invention is to improve the above problems, an object of the present invention is to combine the membrane-free electrolysis reactor and the UV Fenton oxidation process and to reduce the use of the divalent iron catalyst required for the fenton oxidation or photo-pentone oxidation process In addition, to provide a non-degradable wastewater treatment apparatus and method using a complex oxidation process combined with electrolysis and photo-pentone oxidation process to reduce the consumption of hydrogen peroxide.

In addition, another object of the present invention is to decompose organic matter by the free chlorine generated from the electrolyte (NaCl) by the electrolysis reaction to obtain an organic decomposition rate more effective than the conventional electrochemical Fenton oxidation process electrolysis and photo-phentone oxidation It is to provide an apparatus and method for difficult-degradable wastewater treatment using a combined oxidation process combined with a process.

An apparatus for treating hardly decomposable wastewater using a complex oxidation process in which an electrolysis and a photo-pentone oxidation process of the present invention comprises: a wastewater storage tank 10 in which organic wastewater is stored; An electrolyte injector 20 for introducing divalent iron (Fe ²⁺ ) and sodium chloride electrolyte into the organic wastewater supplied from the wastewater storage tank 10; An air supplier (30) for supplying air to dissolve oxygen in the organic wastewater into which the electrolyte is introduced by the electrolyte injector (20); The positive electrode 41 and the negative electrode 42 are alternately stacked, and an electrolyte is introduced and oxygen-dissolved organic wastewater is introduced to oxidize ferric iron from the electrolyte by electrolysis and generate free chlorine, and hydrogen peroxide by dissolved oxygen. A non-diaphragm electrolyzer 40 for decomposing organic matter contained in wastewater by hydroxyl radicals so that a Fenton oxidation reaction is formed to form hydroxyl radicals; UV photoreactor (50) for supplying wastewater fenton oxidized by the electrolytic cell 40 to be photo-oxidized by UV irradiation; A collecting tank 60 through which the treated water photo-oxidized by the UV photoreactor 50 is collected; Characterized in that comprises a.

In addition, the wastewater storage tank 10 and the electrolytic cell 40 is installed between the electrolyte injector 20 and the electrolyte introduced from the electrolyte injector 20 and the organic wastewater supplied from the wastewater storage tank 10 is mixed It characterized in that the line mixer 70 to be further provided.

In addition, the circulation pump 80 is further provided to discharge the electrolyte in the electrolytic cell 40 to the outside and to be combined with the organic waste water mixed with the electrolyte by the line mixer 70 to be introduced into the electrolytic cell 40. It is characterized by.

In addition, the venturi mixer 90 is connected to the circulation pump 80 and mixes the electrolyte discharged from the electrolyzer 40 with the air supplied from the air supplier 30 to dissolve the oxygen in the air. ) Is further provided.

In addition, a porous diffuser 43 is further provided at an inner lower end of the electrolytic cell 40 to allow electrolyte to be injected and oxygen-dissolved organic wastewater to be diffused and supplied to the positive electrode 41 and the negative electrode 42. It is done.

In addition, the treatment water conveying line 100 for conveying the treated water passed through the UV photoreactor 50 to the rear end of the line mixer 70 is characterized in that it is further provided.

In addition, the pH neutralizing chemicals injector 110 for inputting the pH neutralizing chemicals to the treated water collected in the water collecting tank 60 is characterized in that it is further provided.

In addition, the agglomeration sedimentation tank 120 for aggregating and sedimenting the treated water collected in the water collecting tank 60 is characterized in that it is further provided.

The hardly decomposable wastewater treatment method using the combined oxidation process of the electrolysis and photo-pentone oxidation process of the present invention comprises the steps of adding a ferric iron (Fe ^{2 +} ) and sodium chloride electrolyte to the organic waste water; Supplying air to dissolve oxygen in the organic wastewater into which the electrolyte is introduced; Fenton, which oxidizes ferric iron from the electrolyte introduced by electrolysis, generates free chlorine, and generates hydrogen peroxide by dissolving oxygen dissolved in oxygen in the supplied air to form hydroxyl radicals that decompose organic matter contained in wastewater. Oxidation step; Photo oxidation step of irradiating UV to fenton oxidized wastewater; Collecting the photo oxidized treated water; Characterized in that comprises a.

In addition, the electrolyte circulating step of circulating the pentone oxidized electrolyte in the organic wastewater to which the electrolyte before the fenton oxidation reaction is added; Characterized in that further comprises.

In addition, the treatment water conveying step of feeding the mineralized treated water into the organic wastewater to which the electrolyte before the Fenton oxidation reaction is introduced; Characterized in that further comprises.

In addition, the step of adding a pH neutralizing chemical to the collected treated water; Characterized in that further comprises.

In addition, agglomerated and precipitated the collected treated water; Characterized in that further comprises.

In the present invention, since dissolved oxygen in the air supplied from the air supply dissolved hydrogen to generate hydrogen peroxide by electrolysis, there is no need to inject additional hydrogen peroxide (H ₂ O ₂ ) has an economic advantage to reduce the drug cost. In addition, the use of the ferric catalyst can be reduced by the Fenton oxidation reaction and the photo-Fenton oxidation process by UV, and the organic matter is not only decomposed by organic radicals by hydroxyl radicals but also by free chlorine generated from the electrolyte (NaCl) by electrolysis reaction. Decomposition of the organic material has an effect of obtaining an organic decomposition rate more effective than the conventional electrochemical Fenton oxidation process.

The present invention combines a non-diaphragm electrolysis tank and a UV Fenton oxidation process, electrochemically ferric iron (Fe ³⁺ ) used in the hydrogen peroxide and Fenton oxidation process produced without a separate H ₂ O ₂ injection ²⁺ ) to improve the decomposition rate of organic matter by the pentone oxidation reaction by the reaction of the divalent pentone iron catalyst and the photo-pentone oxidation process by UV, and the glass produced from the electrolyte (NaCl) by the electrolysis reaction Chlorine can also decompose organic matters, resulting in more efficient decomposition of organic matters than conventional electrochemical Fenton oxidation processes, and electrolysis and photo-pentene oxidation processes that reduce the use of divalent iron catalysts required for fenton oxidation or photo-pentene oxidation processes. Provided is an apparatus and method for treating hardly degradable wastewater using a combined oxidation process.

Hereinafter, an apparatus and method for treating hardly degradable wastewater using a complex oxidation process in which electrolysis and photo-pentone oxidation process are combined will be described with reference to the accompanying drawings.

First, an apparatus for treating hardly degradable wastewater using a complex oxidation process in which electrolysis and photo-pentone oxidation processes are combined will be described.

1 is a view showing an apparatus for treating hardly degradable wastewater using a complex oxidation process in which electrolysis and photo-pentone oxidation process are combined according to the present invention.

As shown, a non-degradable wastewater treatment apparatus using a complex oxidation process combined with electrolysis and light-pentone oxidation process according to the present invention, wastewater storage tank 10 for storing organic wastewater; An electrolyte injector 20 for injecting ferric iron (Fe ²⁺ ) and sodium chloride electrolyte into the organic wastewater; An air supplier 30 for supplying air to dissolve oxygen in the organic wastewater into which the electrolyte is introduced; A non-diaphragm electrolyzer 40 for oxidizing ferric iron from the electrolyte to generate free chlorine, generating hydrogen peroxide, and causing a Fenton oxidation reaction to form hydroxyl radicals; UV photoreactor (50) for irradiating UV to the efton oxidation wastewater by the electrolytic cell 40; A collecting tank 60 through which treated water photooxidized by UV is collected; It is made, including.

The wastewater storage tank 10 stores organic wastewater, and the acidic electrolyte is introduced from the acidic electrolyte injector 11 into the wastewater storage tank 10.

The electrolyte injector 20 serves to inject divalent iron (Fe ²⁺ ) and sodium chloride (NaCl) electrolyte into the organic wastewater supplied from the wastewater storage tank 10. The charged ferric iron (Fe ²⁺ ) is reacted with hydrogen peroxide to oxidize to trivalent iron (Fe 3+) and undergo a general Fenton oxidation reaction to generate hydroxyl radicals (see Scheme 2).

The hydroxyl radicals are involved in the sterilization and disinfection of almost all contaminants, and are natural substances that are harmless to the human body while exhibiting the most powerful effect of chemical decomposition and removal. In addition, the hydroxyl radical has the strongest oxidizing power (capacitance to disinfect, disinfect, and decompose) after fluorine (F), and is stronger than ozone (O ₃ ) and chlorine (Cl ₂ ), but like fluorine, chlorine, and ozone. It is not toxic or harmful to humans. According to a recent study conducted in the United States, hydroxyl radicals have an oxidation rate 2000 times faster than ozone and 180 times faster than the sun's ultraviolet rays, and are used to decompose and remove air purification and wastewater treatment.

The air supplier 30 serves to supply air so that oxygen is dissolved in the organic wastewater into which the electrolyte is introduced from the electrolyte injector 20. Dissolved oxygen dissolved in the waste water in the negative electrode 42 at low pH (acidic) conditions in the electrolytic cell 40, hydrogen peroxide is generated by the reduction of oxygen by combining with hydrogen ions as shown in [Scheme 3]. It reacts with ferric iron (Fe ²⁺ ) in the injected electrolyte and oxidizes to trivalent iron (Fe ³⁺ ) to induce the Fenton oxidation process to form hydroxyl radicals.

Scheme 3

^{_{O 2 (g) + 2H +}} + 2e - → H 2 O 2 (7)

After the reaction with hydrogen peroxide, oxidized trivalent iron (Fe ³⁺ ) is reduced back to divalent iron (Fe ²⁺ ) by [Scheme 3] to induce a continuous Fenton oxidation reaction.

In the electrolyzer 40, a plurality of positive electrodes 41 and negative electrodes 42 are alternately stacked, and an electrolyte is introduced by electrolysis and an organic waste water in which oxygen is dissolved is introduced to oxidize bivalent iron from an electrolyte by electrolysis. Chlorine is generated, and hydrogen peroxide is generated by dissolved oxygen, which causes the Fenton oxidation reaction to form hydroxyl radicals, thereby decomposing organic substances contained in wastewater by hydroxyl radicals, and forming a membrane.

At this time, the wastewater storage tank 10 and the electrolytic cell 40 is installed between the electrolyte injector 20 and the electrolyte introduced from the electrolyte injector 20 and the organic wastewater supplied from the wastewater storage tank 10 is mixed It is preferable that the line mixer 70 is further provided. The line mixer 70 facilitates mixing of the electrolyte introduced into the organic wastewater.

Chlorine in the sodium chloride electrolyte in the electrolytic cell 40 becomes free chlorine, which is chlorine (Cl ₂ ), hypochlorous acid (HOCl) and hypochlorous ion (OCl ⁻ ), as shown in [Scheme 3]. Decompose organic matter.

Scheme 3

_{^{2Cl - → Cl 2 + 2e -}} (8)

_{Cl 2 + H 2 O → HOCl} + Cl - + H + (9)

^{HOCl → H + + OCl - (} 10)

_{^{6OCl - + 3H 2 O → 2ClO}} 3 - + 4Cl - + 6H + + 3/2 O 2 + 6e - (11)

^{_{2ClO 3 - + 2H 2 O →}} 2ClO 4 - + 4H + + 2e - (12)

_{^{OCl - + 2HOCl → ClO 3 -}} + 2Cl - + 2H + (13)

The circulating pump 80 is discharged to the outside of the electrolytic cell 40 to the outside and is combined with the organic wastewater mixed with the electrolyte by the line mixer 70 so that the circulation pump 80 is introduced into the electrolytic cell 40. It is desirable to increase the organic matter removal efficiency of the organic wastewater.

At this time, the oxygen in the air is connected to the circulation pump 80 so that it is easy to dissolve in the electrolyte, the electrolyte discharged from the electrolytic cell 40 and the air supplied from the air supply 30 is mixed to discharge oxygen in the air Preferably, the venturi mixer 90 is further provided to dissolve in the prepared electrolyte solution.

In addition, it is preferable that a porous diffuser 43 is further provided at an inner lower end of the electrolytic cell 40 to allow an electrolyte to be injected and oxygen-dissolved organic wastewater to be supplied to the positive electrode 41 and the negative electrode 42. Do. When the organic wastewater is diffused to the electrode plate by the porous diffuser 43, the reaction can be induced more effectively, thereby increasing the organic removal efficiency.

Electricity required for electrolysis is supplied from a power supply 44 and a constant amount of voltage and current are supplied to the positive electrode 41 and the negative electrode 42 in a galvano static manner.

The electrode material used in the electrolysis reaction may be a variety of electrodes, but for higher efficiency and economy, a positive electrode 41 uses a DSA (electrode coated with IrO ₂ or RuO ₂ on Ti) electrode and a negative electrode ( 42) inexpensive stainless steel or iron, graphite, and carbon electrodes may be used.

The UV photoreactor 50 is fed to the efton oxidized wastewater by the electrolytic cell 40 and the UV is irradiated so that the additional photo oxidation of (3) of [Scheme 2].

By the continuous process of the fenton oxidation process and the photo oxidation process, the organic material is completely oxidized to CO ₂ and H ₂ O.

The organic matter decomposition rate and the organic matter decomposition rate discharged to the collection tank 60 to be provided with a treated water conveying line 100 for conveying the treated water passed through the UV photoreactor 50 to the rear end of the line mixer 70 as needed. When low, it is preferable to re-introduce into the electrolytic cell 40 so as to decompose the organic material that has not been decomposed.

The sump tank 60 collects the treated water photo-oxidized by the UV photoreactor 50.

Since the treated water collected in the sump tank 60 is acidic, a pH neutralizing chemical injector 110 for introducing a basic pH neutralizing chemical such as NaOH may be further provided.

In addition, it is preferable that the aggregation settling tank 120 to further aggregate and precipitate the treated water collected in the collection tank 60.

The wastewater is treated in the following manner using a hardly decomposable wastewater treatment apparatus using a complex oxidation process in which the electrolysis and the photo-pentone oxidation process are configured as described above.

Ferric iron (Fe ²⁺ ) and sodium chloride electrolyte are added to the organic wastewater to which the acidic electrolyte is added, and air is supplied to dissolve oxygen in the organic wastewater to which the electrolyte is added.

Subsequently, an electrolyte is introduced and air is supplied to electrolyze the organic wastewater in which oxygen is dissolved. At this time, the electrolysis reaction is performed by oxidizing the ferric iron from the injected electrolyte, generating free chlorine, and generating hydrogen radicals by dissolving oxygen in the supplied air to form hydroxyl radicals that decompose organic matter contained in the waste water. Fenton) is an oxidation reaction.

In this case, in order to increase the efficiency of the Fenton oxidation reaction, it is preferable to circulate the Fenton oxidized electrolyte into the organic wastewater to which the electrolyte before the Fenton oxidation is introduced.

Subsequently, the Fenton oxidized wastewater is subjected to photo oxidation which irradiates UV, and the photo oxidized treated water is collected. At this time, when the decomposition of organic matters is low, it is preferable to add the treated mineralized water to the organic wastewater to which the electrolyte before the Fenton oxidation reaction is put and returned. In addition, it is preferable to add a pH neutralizing chemical to the collected treated water.

The collected treated water is preferably coagulated and precipitated.

EXAMPLE

Synthetic wastewater made with 100 ppm of phenol (about 250 ppm based on CODcr) and phenolic wastewater under the same electrolysis conditions to confirm the improvement of organic decomposition effect in the combined oxidation process combined with electrochemical Fenton oxidation process and UV photoreaction process. Phenol decomposition results were compared in diaphragm electrolysis, Electro Fenton and Electro Photo-fenton processes.

1. Experimental conditions

 1) Experimental condition of Electro Photo-fenton process

  CODcr: 250 ppm

  -Phenol conc. 100 ppm

  Initial pH: 3

  Volume: 500 ml

  NaCl conc. 0.3%

-UV: 254nm, 3 low pressure mercury lamps (35 W, 1.65 × 10 ¹⁶ sec / cm ³ )

FeSO _{4 7} H ₂ O conc. 0.25 g / L

  -Air blowing: 50 ml / min

  Current: 3 A

  -Electrode size: 5 × 6 cm

-Anode: 4 IrO ₂ / Ti Mesh electrodes

  -Cathode: 5 stainless still plate electrodes

 2) Electro Fenton process test condition

  CODcr: 250 ppm

  -Phenol conc. 100 ppm

  Initial pH: 3

  Volume: 500 ml

  NaCl conc. 0.3%

FeSO _{4 7} H ₂ O conc. 0.25 g / L

  -Air blowing: 50 ml / min

  Current: 3 A

  -Electrode size: 5 × 6 cm

-Anode: 4 IrO ₂ / Ti Mesh electrodes

  -Cathode: 5 stainless still plate electrodes

 3) Electrolysis process test condition

  CODcr: 250 ppm

  -Phenol conc. 100 ppm

  Initial pH: 3

  Volume: 500 ml

  NaCl conc. 0.3%

  Current: 3 A

  -Electrode size: 5 × 6 cm

-Anode: 4 IrO ₂ / Ti Mesh electrodes

  -Cathode: 5 stainless still plate electrodes

2. Experimental Results

FIG. 2 is a diagram illustrating a complex oxidation process experiment apparatus in which a membrane-free electrolysis cell and a photoreactor used in an experiment are disposed, and an electrolyzer 40 and a UV photoreactor 50 are continuously disposed and air is supplied to an air supply 30. It was to be supplied to the porous diffuser 43 installed at the bottom of the electrolyzer.

3 is a phenol according to the reaction time in the photo-fenton oxidation process (Electro Photo-fenton Process), a general Fenton oxidation process (Electro Fenton Process) and a general non-electrode electrolytic cell (Electrolysis) ( Phenol) is a comparison of the COD removal rate of the solution. Experimental conditions of each process are as described above. The COD removal rate in the Electro Photo-fenton Process reached about 66% for 60 minutes under the same electrolysis conditions, whereas the Electro Fenton Process and the membraneless electrolytic cell electrolysis process ( COD removal rates in electrolysis were 50% and 34%, respectively.

Figure 4 is an electrolytic cell during the electrolysis reaction in the photo-fenton oxidation process (Electro Photo-fenton Process), a general Fenton oxidation process (Electro Fenton Process) and a general non-deposited electrolysis cell (Electrolysis) according to the present invention It is a graph showing the change of the voltage applied to. As shown, it can be seen that all three processes remain nearly constant at about 4.8 V at about 4.8-5 V depending on the reaction time.

FIG. 5 is a graph showing solution pH changes in an electro-photon fenton process, a general fenton oxidization process, and a general membrane-free electrolytic cell electrolysis process according to the present invention. to be.

As shown, it can be seen that all three processes appear constant at about 3.57 at initial pH 3.

Taken together, the photo-pentone oxidation process according to the present invention has a constant voltage change and a constant pH even without a separate pH adjustment. The removal rate of phenol is higher than that of the general fenton oxidation process and the electroless cell electrolysis process. As it appears, it can be seen that it is advantageous over other processes.

1 is a view showing an apparatus for treating hardly degradable wastewater using a complex oxidation process in which electrolysis and photo-pentone oxidation process are combined according to the present invention.

2 is a view showing a combined oxidation process experiment apparatus combined with a membrane-free electrolytic cell and a photoreactor used in the experiment.

3 is a phenol according to the reaction time in the photo-fenton oxidation process (Electro Photo-fenton Process), a general Fenton oxidation process (Electro Fenton Process) and a general non-electrode electrolytic cell (Electrolysis) ( Phenol) graph showing the removal rate of COD.

Figure 4 is an electrolytic cell during the electrolysis reaction in the photo-fenton oxidation process (Electro Photo-fenton Process), a general Fenton oxidation process (Electro Fenton Process) and a general non-deposited electrolysis cell (Electrolysis) according to the present invention Graph showing the change in voltage across

FIG. 5 is a graph showing solution pH changes in an electro-photon fenton process, a general fenton oxidization process, and a general membrane-free electrolytic cell electrolysis process according to the present invention. .

* Description of the symbols for the main parts of the drawings *

10: wastewater storage tank 20: electrolyte injector

30: air supply 40: electrolytic cell

41: positive electrode 42: negative electrode

43: porous diffuser 44: power supply

50: UV photoreactor 60: sump

70: line mixer 80: circulation pump

90: Venturi mixer 100: treated water return line

110: pH neutralizing chemical injector 120: flocculation settling tank

Claims (13)

A wastewater storage tank 10 in which organic wastewater is stored; An electrolyte injector 20 for introducing divalent iron (Fe ²⁺ ) and sodium chloride electrolyte into the organic wastewater supplied from the wastewater storage tank 10; An air supplier (30) for supplying air to dissolve oxygen in the organic wastewater into which the electrolyte is introduced by the electrolyte injector (20); A plurality of positive electrodes 41 and negative electrodes 42 are alternately stacked, electrolyte is introduced, and organic wastewater in which oxygen is dissolved is introduced to oxidize ferric iron from the electrolyte by electrolysis and generate free chlorine, and hydrogen peroxide by dissolved oxygen. A non-diaphragm electrolyzer 40 for decomposing organic matter contained in wastewater by hydroxyl radicals so that a Fenton oxidation reaction is formed to form hydroxyl radicals; UV photoreactor (50) for supplying wastewater fenton oxidized by the electrolytic cell 40 to be photo-oxidized by UV irradiation; A collecting tank 60 through which the treated water photo-oxidized by the UV photoreactor 50 is collected; Refractory wastewater treatment apparatus using a complex oxidation process combined electrolysis and light-pentone oxidation process comprising a. The method of claim 1, Installed between the wastewater storage tank 10 and the electrolyzer 40 and connected to the electrolyte injector 20 to mix the electrolyte introduced from the electrolyte injector 20 with the organic wastewater supplied from the wastewater storage tank 10. The apparatus for treating hardly decomposable wastewater using a complex oxidation process in which an electrolysis and photo-pentone oxidation process are combined, further comprising a line mixer (70). The method of claim 2, It is further provided that the circulation pump 80 to discharge the electrolyte in the electrolytic cell 40 to the outside and to be combined with the organic wastewater mixed with the electrolyte by the line mixer 70 to be introduced into the electrolytic cell 40. Refractory wastewater treatment system using a complex oxidation process combined with electrolysis and light-pentone oxidation process. The method of claim 3, wherein The venturi mixer 90 is connected to the circulation pump 80 and mixes the electrolyte discharged from the electrolyzer 40 with the air supplied from the air supplier 30 to dissolve the oxygen in the air. Refractory wastewater treatment apparatus using a complex oxidation process combined electrolysis and light-pentone oxidation process characterized in that it further comprises. The method of claim 1, At the inner bottom of the electrolyzer 40, an electrolyte is introduced and a porous diffuser 43 for dispersing and supplying organic wastewater in which oxygen is dissolved is supplied to the positive electrode 41 and the negative electrode 42. Refractory wastewater treatment system using complex oxidation process combined with electrolysis and photo-pentone oxidation process. The method of claim 2, Combined oxidation combined with electrolysis and light-pentone oxidation process, characterized in that the treatment water conveying line 100 for conveying the treated water passed through the UV photoreactor 50 to the rear end of the line mixer 70 is further provided. Refractory wastewater treatment apparatus using a process. The method according to any one of claims 1 to 6, The pH neutralization chemical injector 110 for injecting the pH neutralizing chemical into the treated water collected in the water collecting tank 60 is characterized in that it is difficult to decompose using a combined oxidation process combined with electrolysis and light-pentone oxidation process Wastewater treatment unit. The method according to any one of claims 1 to 6, Aggregate sedimentation tank 120 for aggregating and precipitating the treated water collected in the water collecting tank 60, characterized in that it further comprises an electrolysis and light-pentone oxidation process combined with a decomposable wastewater treatment apparatus using a combined oxidation process. Adding ferric iron (Fe ²⁺ ) and sodium chloride electrolyte to the organic wastewater; Supplying air to dissolve oxygen in the organic wastewater into which the electrolyte is introduced; Fenton, which oxidizes ferric iron from the electrolyte introduced by electrolysis, generates free chlorine, and generates hydrogen peroxide by dissolving oxygen dissolved in oxygen in the supplied air to form hydroxyl radicals that decompose organic matter contained in wastewater. ) Oxidation reaction step; A photo oxidation step of irradiating UV to the fenton oxidized wastewater; Collecting the photo oxidized treated water; Hardly-decomposable wastewater treatment method using a complex oxidation process combined electrolysis and photo-pentone oxidation process, characterized in that comprises a. The method of claim 9, An electrolyte circulating step of circulating the pentone oxidized electrolyte in the organic wastewater to which the electrolyte before the fenton oxidation is introduced; Hardly-decomposable wastewater treatment method using a complex oxidation process combined electrolysis and photo-pentone oxidation process, characterized in that further comprises. The method of claim 9, A treated water conveying step of feeding the photooxidized treated water into the organic wastewater into which the electrolyte before the Fenton oxidation reaction is fed; Hardly-decomposable wastewater treatment method using a complex oxidation process combined electrolysis and photo-pentone oxidation process, characterized in that further comprises. The method according to any one of claims 9 to 11, Adding a pH neutralizing agent to the collected treated water; Hardly-decomposable wastewater treatment method using a complex oxidation process combined electrolysis and photo-pentone oxidation process, characterized in that further comprises. The method according to any one of claims 9 to 11, Flocculating and sedimenting the collected treated water; Hardly-decomposable wastewater treatment method using a complex oxidation process combined electrolysis and photo-pentone oxidation process, characterized in that further comprises.

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