KR102122384B1 - Treatment ystem of wastewater and method using the same - Google Patents

Abstract

For COD and TN simultaneous inducers such as ethanolamine (Ethanolamine, ETA) contained in pretreated concentrated water or raw waste water, the COD-inducing component is oxidized to CO ₂ using persulfate, and TN is ammonia nitrogen (NH ₃ -N) persulfuric acid reaction tank, and a treated salt in the persulfuric acid reaction tank to oxidize the separated nitrogen to sodium gas (N ₂ ) using sodium hypochlorite (NaOCl) chloride ion (Cl ^-) that remains on a number of the ammonium nitrogen remaining in the production converted to sodium hypochlorite (NaOCl) by electrolysis (NH ₃ -N) and simultaneously oxidized to nitrogen gas (N ₂₎ some COD Disclosed is a complex wastewater treatment system comprising an oxidizing electrolysis tank and a complex wastewater treatment method using the same.

Description

Complex wastewater treatment system and complex wastewater treatment method using the same{TREATMENT YSTEM OF WASTEWATER AND METHOD USING THE SAME}

The present invention relates to a method for treating refractory organic matter, and more particularly, to a system and method for treating wastewater generated in a secondary system of a nuclear power plant.

Chemicals currently used as pH regulators for secondary system water in nuclear power plants include ammonia, morpholine, and ethanolamine (ETA). However, most nuclear power plants in Korea and abroad are using ethanolamine rather than ammonia as a pH regulator. That is, ethanolamine can maintain a high pH even in a small amount under high temperature and high pressure conditions, thereby reducing the load of a condensate polishing plant (CPP), and the cation exchange resin provides high sodium selectivity in amine mode. Since it has the advantage of minimizing the influx of sodium into the steam generator and the corrosion of the steam generator, etc., the use of ethanolamine as a pH adjusting agent to replace ammonia is constantly increasing. However, the use of ethanolamine has been a factor in increasing the COD and T-N of effluent by wastewater generated during regeneration of multiple desalination facilities. The system water circulating in the secondary system is regenerated periodically to remove impurities using ion exchange resins of a multi-salt desalination facility. At this time, compounds such as ethanolamine, hydrazine, and ionic substances in the system water are discharged together. These compounds contain a large amount of nitrogen compounds and organic substances at concentrations of several hundred to several thousand, thereby simultaneously inducing COD and T-N.

In the case of a domestic nuclear power plant, ethanolamine (ETA) wastewater containing high-concentration organic substances and sulfuric acid generated during regeneration of multiple desalination facilities is mixed with other system water and transferred to a wastewater treatment facility, followed by precipitation after coagulation reaction, a physical and chemical treatment method. The primary treatment is performed through a process, etc., and the ETA, which is a hardly decomposable substance, is processed through electrolysis. However, due to various scale-causing substances in salt and multiple desalination facilities recycled waste water and electrothermal decomposition characteristics of ETA, it has not been possible to effectively treat ETA wastewater. In addition, it is necessary to develop more effective technology because it cannot actively cope with environmental laws and regulations that will be strengthened in the future.

Conventional foreign technology applies a complex treatment process that combines physicochemical, biological, and electrochemical treatment methods to treat ETA-containing wastewater. Technical examples for the treatment of wastewater containing ETA and non-degradable organics are as follows.

In order to treat organic wastewater containing ETA, hydrazine, and ammonia, Kyushu Electric Power Company maintains the pH of organic wastewater at 5~11, injects more than 5000 ppm of chlorine ions into it, passes the electrolysis device, and then ultraviolet rays. Decomposes organics in the reactor. This wastewater was found to be effective in reducing the COD of organic wastewater with a COD of 1000 ppm or more and an electrical conductivity of 100 uS/cm or more as a method to be recovered when the target water quality is reached while continuously circulating the electrolysis and UV treatment processes.

Japan's Ikata nuclear power plant wastewater treatment process uses physicochemical treatment processes to precipitate and remove suspended and sedimentable oil and inorganic substances, electrolysis of COD and TN inducers dissolved in water, catalytic oxidation, and activated carbon. To remove it.

However, Kyushu Electric Power Company's treatment method is similar to that of Korea, and it is expected that the treatment effect of the electrolysis device will be inadequate due to the scale-causing substances contained in the waste water of nuclear power plants. Although the performance of the electrolysis device is guaranteed by excluding the sex substances, the treatment process is complicated and has a number of maintenance factors, which is difficult to operate.

On the other hand, another conventional technique for the treatment of non-degradable COD material is the Fenton oxidation method, which is one of the physical and chemical treatment methods. The Fenton oxidation method uses the Fenton reaction, which is an oxidation reaction of organic substances, and is known as an effective method for oxidizing contaminants by reacting divalent iron ions with hydrogen peroxide to generate hydroxy radicals (-OH) with strong oxidizing power. However, oxidation of high concentration ETA, a decomposable substance by Fenton's reaction, requires destruction of carbon covalent bonds of ETA and treatment with harmless CO ₂ , so an excess of hydrogen peroxide and iron sulfate are required, and a large amount of sludge is generated due to the input iron sulfate There is a disadvantage in that economic efficiency is poor. And since the Fenton reaction is effective only in acidic conditions and is very sensitive to pH conditions, there is a problem that precise management of pH is required.

In addition, the ozone treatment method in the advanced oxidation treatment process is to oxidize and treat a hardly decomposable substance by using the fact that ozone generated by combining three oxygen atoms is a very strong oxidizing agent. The ozone is produced by an electric discharge method, a photochemical reaction method, and the like, and an electric discharge method in which a large amount of ozone is produced with relatively high efficiency is most commonly used. However, ozone is an oxidizing agent that is advantageous in alkalinity, and acts as an oxidizing agent by decomposing ozone under alkaline conditions to generate hydroxy radicals. However, there is a disadvantage that such ozone is not easily dissolved in water and is sensitive to pH like the Fenton reaction. In addition, it exhibits a characteristic irritating odor even at low concentrations of 0.02 ppm or less, and is known to be harmful to the human body when exposed for a long time at a concentration of 0.02 ppm or more.

Republic of Korea Registered Patent No. 10-1378428

The present invention was created to solve the above problems, and a method for treating ethanolamine (Ethanolamine, ETA)-based wastewater generated in a water treatment system of a multiple desalination facility including wastewater generated from secondary systems such as power plants and nuclear power plants. In order to provide a complex wastewater treatment system capable of completely treating COD and TN that are not decomposed even after conventional physicochemical treatment and advanced oxidation treatment (electrolysis) and a complex wastewater treatment method using the same.

For COD and TN simultaneous inducers such as ethanolamine (Ethanolamine, ETA) contained in pretreated concentrated water or raw waste water, the COD-inducing component is oxidized to CO ₂ using persulfate, and TN is ammonia nitrogen (NH ₃ -N) persulfate reaction tank; A _secondary salt reaction tank for oxidizing the separated nitrogen treated and treated in the persulfuric acid reactor with nitrogen gas (N ₂ ) using sodium hypochlorite (NaOCl); And chlorine ion (Cl ^-) remaining in the treated process in the reaction vessel chayeom the ammonium nitrogen (NH ₃ -N) and COD components to be part of the raw produce converted into sodium hypochlorite (NaOCl) to the electrolytic residue It characterized in that it comprises an; electrolysis tank to oxidize.

For COD and TN simultaneous inducers such as ethanolamine (Ethanolamine, ETA) contained in pretreated concentrated water or raw waste water, the COD-inducing component is oxidized to CO ₂ using persulfate, and TN is ammonia nitrogen (NH ₃ -N) persulfate reaction tank; The conversion produces separated by sodium hypochlorite (NaOCl) ammonium nitrogen (NH ₃ -N) nitrogen ^gas and the chloride ion (Cl) contained in the treated water by electrolyzing the water treatment process in the reaction vessel with sulfuric acid It is characterized in that it comprises; (N ₂ ) and an electrolysis tank that oxidizes the remaining COD components while oxidizing.

As a result, wastewater generated in a multiple desalination plant using ETA used as a pH regulator of secondary system water such as a nuclear power plant is separated and processed according to concentration to effectively remove COD and TN caused by ETA. Can.

Here, it is preferable to further include a catalyst device installed in the persulfuric acid reaction tank so that the persulfate is mixed and the persulfate generates sulfate radicals.

Thus, the ETA contained in the raw waste water can be oxidized to CO ₂ through the persulfuric acid reaction in the persulfuric acid reaction tank, and TN can be separated into ammonia nitrogen (NH ₃ -N).

In addition, the catalytic device preferably includes any one of a heater installed to heat the inside of the persulfate reaction tank and an ultraviolet irradiator.

As a result, the persulfuric acid reaction is effectively performed by setting the temperature or wavelength suitable for the persulfuric acid reaction, thereby shortening the wastewater treatment process time and improving the treatment efficiency.

In addition, the persulfate input to the persulfate reaction tank is preferably liquid sodium persulfate (Na ₂ S ₂ O ₈ ) or liquid potassium persulfate (K ₂ S ₂ O ₈ ).

In addition, the persulfate reaction in the persulfuric acid reaction tank circulates the treated water, thereby raising the temperature of the concentrated water or raw wastewater input to the persulfuric acid reaction tank to a set temperature, and setting the temperature of the persulfate-reacted treated water to a set temperature. It is better to further include a heat exchanger lowered to.

As a result, the temperature of the raw waste water can be preliminarily raised through the heat exchange between the treated water and the raw waste water whose temperature has increased for the persulfuric acid reaction, thereby shortening the treatment time and saving energy for raising the temperature to the catalytic reaction temperature. . In addition, it is possible to cool the high-temperature treated water without a separate cooling facility, thereby simplifying the facility and reducing costs.

In addition, it is preferable to further include a pH adjusting tank for adjusting the pH to a desired set range by adding a pH adjusting agent to the treated water discharged from the persulfate reaction tank.

Further, the rest of the residual chlorine in the treated water after electrolysis in the electrolyzer of chloride ion (Cl ^-) preferably further includes a neutralizing device that can be reduced.

At this time, the neutralization means is a chemical reactor for reducing the residual chlorine component through a catalytic reaction or an adsorption tower that adsorbs and removes the residual chlorine component through a chemical reaction with the residual chlorine component by injecting a reducing chemical. It is preferred that the catalyst tower is composed of any one or more combinations.

Thereby, the treated wastewater can be neutralized and discharged or reused in a safe state.

In addition, it is preferable to further include a reverse electrodialysis power generation device for producing electrical energy using the treated water discharged from the neutralizing means. Thus, it can be used to generate energy by using the treated water after the treatment process is completed.

The reverse electrodialysis power generation apparatus includes an anode and a cathode that are installed to face each other; It includes; a cation exchange membrane and an anion exchange membrane are alternately stacked between the anode and the cathode; includes, a unit cell comprising a fresh water flow path and a brine flow path partitioned by the cation exchange membrane and the anion exchange membrane, the It is configured to have a structure in which a plurality of unit cells are stacked.

In addition, the persulfate may be configured to be produced and supplied through an electrolysis device that is produced through an electrolysis reaction of sulfur oxides.

Such an electrolysis device has a diaphragm-type electrolysis tank having an ion exchange membrane, and an electrochemical conversion means for converting ammonium sulfate into ammonium persulfate by electrochemical reaction; And a chemical reaction tank for producing sodium persulfate or potassium persulfate by reacting the produced ammonium persulfate with caustic soda or potassium hydroxide.

In addition, the ammonium sulfate is preferably supplied from a scrubber that reacts ammonia degassed in raw waste water with a sulfuric acid solution to recover in concentrated ammonium sulfate form.

Thus, it is possible to produce sodium persulfate or potassium persulfate using ammonia from the treatment of raw waste water, thereby producing an oxidizing agent required for wastewater treatment.

In addition, it is preferable that the sodium hypochlorite supplied to the above-mentioned salting reaction tank is produced and supplied through electrolysis of seawater or brine. In this way, the cost can be reduced by easily producing and supplying the oxidizing agent in the field.

In addition, in the pre-treated concentrated water or raw waste water, the pre-treated wastewater is passed through the pre-treated wastewater to further comprise a concentrating unit to separate into concentrated water and permeated water, and the concentrated water discharged from the concentrated unit is It is preferably configured to be supplied to the persulfuric acid reaction tank.

In addition, the pre-treated concentrated water or raw waste water is a wastewater of low concentration (COD 15mg/L or less), medium concentration (COD 16 ~ 320mg/L or less), high concentration (COD 350mg/L or more) It is preferably configured to be separated into a separate stream, and configured to supply wastewater obtained by pre-treating wastewater consisting of each separate stream as the pretreated concentrated water or raw waste water to the persulfuric acid reactor.

In addition, the persulfuric acid reaction tank is composed of a plurality of reaction tanks, and the low-concentration and medium-concentration wastewater is introduced into one persulfuric acid reaction tank through the concentrated section that separates the concentrated water and the permeated water from separate streams. , High-concentration wastewater is more preferably configured so that the raw wastewater is introduced into another persulfate reactor.

This enables more efficient and economical wastewater treatment.

In addition, the complex wastewater treatment method of the present invention for achieving the above object, the treatment of wastewater containing COD and TN simultaneous inducers generated in the secondary system generated wastewater such as power plants, nuclear power plants, water treatment systems of multiple desalination facilities In the method, persulfate is injected into a persulfuric acid reaction tank containing concentrated or raw wastewater in which wastewater is concentrated to oxidize the COD component contained in the concentrated or raw wastewater to CO ₂ , and at the same time, TN is ammonia nitrogen (NH ₃ -N) step of carbon oxidation; A first step of nitrogen oxidation in which the ammonia nitrogen separated in the carbon oxidation step is first oxidized with nitrogen gas (N ₂ ) using sodium hypochlorite (NaOCl); And chlorine ions (Cl ⁻ ) remaining in the treated water reacted in the first step of nitrogen oxidation are regenerated with sodium hypochlorite (NaOCl) through an electrolysis tank to remove the remaining ammonia nitrogen (NH ₃ -N) in the treated water. It is characterized in that it comprises a second step of nitrogen oxidation to oxidize some of the remaining COD components while simultaneously oxidizing with nitrogen gas (N ₂ ).

In addition, the complex wastewater treatment method according to another aspect of the present invention for achieving the above object, includes secondary system-generated wastewater such as a power plant, a nuclear power plant, and COD and TN simultaneously generated in a water treatment system of a multiple desalination facility. In the treatment method of one wastewater, persulfate is injected into a persulfuric acid reaction tank containing concentrated or raw wastewater in which the wastewater is concentrated, and contained in the concentrated or raw wastewater. Carbon oxidation step of oxidizing the COD component with CO ₂ and separating TN into ammonia nitrogen (NH ₃ -N); And a chlorine ion (Cl ^-) contained in the number of treatment processes in the carbon oxidation ^{step, wherein} the process produces switching into sodium hypochlorite (NaOCl) while circulating the twos electrolysis with chlorine ions (Cl) contained in the number of the processing Characterized in that it comprises a; nitrogen oxidation step of oxidizing some of the remaining COD component while oxidizing the ammonia nitrogen (NH ₃ -N) contained in water with nitrogen gas (N ₂ ).

In addition, it is preferable to further include a catalytic reaction step in which a persulfate is mixed with the persulfuric acid reaction tank and a sulfate group is generated at the same time using a catalytic device installed in the persulfuric acid reaction tank.

In addition, it further comprises a heat exchange step of circulating the treated water that has undergone the carbon oxidation step to a heat exchanger to increase the temperature of the concentrated or raw wastewater flowing into the heat exchanger and lowering the temperature of the treated water in the persulfuric acid reactor. desirable.

Accordingly, a more efficient and economical processing process can be secured.

In addition, after the final treatment step in the nitrogen oxide or nitrogen phase oxidation step 2, the residual chlorine component to be the processing of chloride ion (Cl ^-) preferably further includes a neutralization step can be reduced.

Here, the neutralization step is preferably composed of a combination of any one or more of a neutralization method by a chemical reaction, a neutralization method by adsorption, or a neutralization method by a catalyst.

In addition, a reverse electrodialysis power generation step of generating power while passing the treated water that has undergone the neutralization step through the reverse electrodialysis power generation device may be further included.

In addition, it is preferable to further include a concentration step of filtering the pre-treated wastewater to obtain concentrated water from the pre-treated concentrated water or raw waste water and separating it into concentrated water and permeated water to generate the concentrated water.

Here, the pre-treated concentrated water or raw waste water has low concentration (COD 15 mg/L or less), medium concentration (COD 16 to 320 mg/L or less), and high concentration (COD 350 mg/L or more) of secondary system generated waste water such as power plants. It is more preferable to separate the wastewater into separate streams, pretreat the wastewater consisting of each separate stream, and then input the wastewater obtained as concentrated concentrated or raw waste water into the persulfuric acid reaction tank and then treat it through the carbon oxidation step. desirable.

At this time, in the carbon oxidation step, a plurality of persulfuric acid reaction tanks are formed, and concentrated water condensing the low-concentration wastewater in a separate stream and concentrated water condensing the medium-concentration wastewater in a separate stream are introduced into one persulfuric acid reaction tank. And, it is more preferable to go through the carbon oxidation step to treat the high-concentration wastewater by introducing raw wastewater into another persulfate reactor in a separate scrim.

In addition, the pre-treated wastewater preferably includes wastewater obtained by pre-treatment of oil wastewater among wastewater discharged from a complex desalination facility.

Thus, it is possible to pre-treat various types of wastewater and classify and treat the concentrated concentrated water.

In addition, further comprising the step of producing and supplying the persulfate through a separate electrolysis device for the production of persulfate, the step of supplying the persulfate is produced through an electrolysis device, the diaphragm-type electricity having an ion exchange membrane An electrochemical conversion step having a decomposition tank and converting ammonium sulfate into ammonium persulfate by electrochemical reaction; And a chemical reaction step of reacting ammonium persulfate produced in the electrochemical conversion step with caustic soda or potassium hydroxide to produce sodium persulfate or potassium persulfate.

In addition, the ammonium sulfate, the step of degassing in the ammonia gas phase through the degassing process of the raw waste water; It is more preferable to supply the degassed ammonia to a scrubber and absorb the ammonia using a sulfuric acid solution as an absorbing liquid to form ammonium sulfate.

As a result, sodium persulfate or potassium persulfate can be produced using ammonia generated during the wastewater treatment process, thereby reducing the cost of wastewater treatment by reusing ammonia and omitting the facility to separately store and supply sodium persulfate or potassium persulfate. There is an advantage to do.

In addition, it is preferable that the sodium hypochlorite used in the first step of nitrogen oxidation is produced and supplied by electrolysis of seawater or brine.

In this way, it is possible to reduce the operation cost as well as simplify the equipment by generating and supplying the oxidant directly in the field.

According to the complex wastewater treatment system and treatment method of the present invention, COD and TN such as ethanolamine (Ethanolamine, ETA) generated in the secondary system generated wastewater such as a power plant, a nuclear power plant, and a plurality of desalination facilities are simultaneously processed. In treating wastewater containing inducers, COD and TN, which are not decomposed even after conventional physicochemical treatment and advanced oxidation treatment (electrolysis), can be completely treated so that nuclear power plants can be operated stably and efficiently.

In particular, by setting the treatment process differently according to the type and concentration of the raw waste water, the load according to the treatment process of the whole raw waste water is reduced, and the optimum treatment process according to the concentration is applied to increase the treatment process efficiency and increase the treatment time. It has the advantage of being able to shorten and reduce costs.

It also has the advantage of producing energy from wastewater through reverse electrodialysis power generation.

In particular, it is possible to fundamentally solve problems caused by scale induction when salt is administered for electrolysis of raw waste water as in the prior art.

1 is a schematic configuration diagram showing a complex wastewater treatment system according to an embodiment of the present invention.
Figure 2 is a flow chart showing a composite wastewater treatment method according to an embodiment of the present invention.
3 is a process diagram showing a composite wastewater treatment system and a treatment method to which the composite wastewater treatment system according to an embodiment of the present invention is applied.
FIG. 4 is a schematic configuration diagram for explaining the reverse electrodialysis power generation apparatus shown in FIG. 1.
5 is a schematic configuration diagram showing a complex wastewater treatment system according to another embodiment of the present invention.
6 is a schematic configuration diagram showing a complex wastewater treatment method according to another embodiment of the present invention.

Hereinafter, a composite wastewater treatment system according to a preferred embodiment of the present invention and a composite wastewater treatment method using the same will be described in detail with reference to the accompanying drawings.

1 is a schematic configuration diagram showing a complex wastewater treatment system according to an embodiment of the present invention. 2 is a view showing a schematic process sequence for explaining a composite wastewater treatment method according to an embodiment of the present invention.

The complex wastewater treatment system 100 according to an embodiment of the present invention with reference to FIG. 1 includes a concentrating unit 101 for concentrating pre-treated wastewater pre-processing the raw wastewater generated from the source wastewater generating source, and the raw wastewater or the concentrating unit ( 101) a persulfuric acid reaction tank 110 that receives and processes the concentrated water treated, and a heat exchanger 120 that heats the temperature of raw waste water or concentrated water using heat generated from the persulfuric acid reaction tank 110, and PH adjustment tank 130 for adjusting the pH of the treated water discharged from the sulfuric acid reaction tank 110, a salt-retarding reaction tank 140, an electrolysis tank 150, a neutralization means 160 and a reverse electrodialysis power generation device (RED; 170) ).

Here, the raw wastewater generated from the source wastewater source may include wastewater generated from a secondary system such as a power plant or a nuclear power plant, and ethanolamine (ETA)-based wastewater generated from a water treatment system of a plurality of desalination facilities. . However, the present invention is not limited to such wastewater, and can be applied to various wastewater including inducers (such as ethanolamine) that simultaneously induce COD and TN as the wastewater.

More specifically, raw waste water can be classified into low, medium and high concentration raw waste water. The low-concentration raw wastewater may include treated water from a general water treatment system, wastewater from a steam generator, low-concentration raw wastewater (CPP Low) generated in a complex desalination facility, and contaminated water mixed with oil. Among them, the CPP Low can be set to a standard of COD=15mg/L, T-N=25mg/L, SS=300, I,C=400㎲/cm or less.

The medium concentration raw waste water (CPP mid) is wastewater from a complex desalination facility, with COD= 15~320mg/L or less, TN=25~320mg/L, SS=300~500, IC=400~26,800㎲/cm Can be set.

The high-concentration raw wastewater (CPP High) is wastewater from a complex desalination facility, and may be set to COD=350mg/L, T-N=500mg/L, SS=50, I.C=105,000㎲/cm or more.

Among the raw wastewater classified as described above, high concentration raw wastewater (CPP High) is supplied to the persulfate reaction tank 110 as it is.

And the low-concentration raw waste water is supplied to the concentration unit 101 after a pre-treatment process. In addition, the intermediate concentration raw waste water is supplied to the concentration unit 101 immediately after passing through the simple filtration filter as a pre-treatment process.

* The thickening unit 101 is to filter the pre-treated low-concentration mixed wastewater or medium-concentrated raw wastewater (CPP Mid) into separated into concentrated water and permeated water, and may be composed of at least one of RO, NF, EDR, and CDI. Can. The concentrated water discharged from the concentration unit 101 is supplied to the persulfuric acid reaction tank 110.

In the persulfuric acid reaction tank 110, persulfate is injected and mixed to allow persulfuric acid reaction with the supplied high-concentration raw waste water or the concentrated water discharged from the concentrator 101. The persulfate injected into the persulfuric acid reaction tank 110 oxidizes COD caused by ETA contained in raw waste water or concentrated water to CO ₂ , and at the same time separates TN into ammonia nitrogen (NH ₃ -N). You will go through the process.

In addition, it is preferable that the persulfate reaction tank 110 is further equipped with a catalytic device that causes catalysis to be mixed with raw waste water or concentrated water to generate sulfate radicals at the same time.

The catalyst device may include at least one of the heater 111 and the ultraviolet irradiator 113. The heater 111 is installed inside the persulfuric acid reaction tank 110, and is heated so that the persulfuric acid reaction temperature of the raw wastewater can be adjusted in the range of 60 to 90°C.

The ultraviolet irradiator 113 is installed in the persulfuric acid reaction tank 110 and irradiates a wavelength of 180 to 280 nm, so that the persulfate is mixed into the persulfuric acid reaction tank 110 and simultaneously acts as a catalyst to produce a sulfate base. Any one of the heater 111 and the ultraviolet irradiator 113 as described above may be installed, or both may be installed.

In addition, the persulfate injected into the persulfate reaction tank 110 is preferably 1-30 wt% of liquid sodium persulfate (Na ₂ S ₂ O ₈ ) or liquid potassium persulfate (K ₂ S ₂ O ₈ ).

Here, the sodium persulfate or potassium persulfate may be produced by the persulfate production means 180 and supplied to the persulfate reaction tank 110. At this time, the persulfate production means 180 is preferably an electrolysis device that converts sulfur oxides into persulfate by electrolysis. The sodium persulfate or potassium persulfate is produced and supplied by the persulfate production means 180.

Here, the electrolysis device, which is a means for producing persulfate 180, has a diaphragm-type electrolysis tank equipped with an ion exchange membrane, and electrochemical conversion means 182 for electrochemical reaction of ammonium sulfate to ammonium persulfate and the produced fruit It is preferably composed of a chemical reaction tank 183 that produces sodium persulfate or potassium persulfate by reacting ammonium sulfate with caustic soda or potassium hydroxide. In addition, sodium sulfate or potassium sulfate may be electrolyzed as a raw material to directly produce sodium persulfate or potassium persulfate. The sodium persulfate or potassium persulfate produced in the chemical reaction tank 183 is supplied to and stored in the storage tank 184, and may be supplied to the persulfate reaction tank 110 if necessary.

In addition, the ammonium sulfate may be produced and supplied through a scrubber 181 that reacts deaerated ammonia with a sulfuric acid solution through a process of degassing ammonia from the raw waste water and recovers it in a concentrated ammonium sulfate form.

The ammonia degassing process may include a pretreatment step of removing foreign substances contained in raw waste water or agglomerating and removing the foreign substances. In addition, the pre-treatment step may be any one of one or more chemical treatment steps, biological treatment steps, physical and chemical treatment steps, and electrochemical treatment steps. Ammonia may be degassed in the process of treating the raw waste water through these pretreatment steps, and the degassed ammonia may be produced and supplied using persulfate production means 180 as described above. Therefore, it can be used to generate an oxidizing material that treats wastewater by recycling ammonia gas generated during the treatment of raw wastewater, thereby reducing wastewater treatment costs and reusing by-products.

On the other hand, since the persulfuric acid reaction temperature in the persulfuric acid reaction tank 110 is maintained at 60 to 90°C, the temperature of the treated water discharged from the persulfuric acid reaction tank 110 is high, so it is circulated to the heat exchanger 120 It is preferable to lower the temperature through heat exchange with raw waste water or concentrated water that is introduced into the persulfuric acid reaction tank 110.

To this end, the heat exchanger 120 is disposed such that the raw waste water supply line 11 and the discharge line 115 of the treated water discharged from the persulfuric acid reactor 110 can exchange heat while simultaneously passing. Therefore, by the heat exchanger 120, the treated water increases the temperature of the wastewater (raw waste water, concentrated water) of the wastewater supply line 11 to a temperature of 45 to 70°C while passing through the heat exchanger 120, and the treated water It can be lowered to the range of 35 to 45°C. Therefore, there is an advantage in that it is possible to reduce the time required for heating the raw wastewater or the concentrated water flowing into the persulfuric acid reaction tank 110 to the persulfuric acid reaction temperature, and to save driving energy of the heater 111.

In addition, since there is no need to install a separate cooling device to lower the temperature of the treated water, it is possible to simplify the treatment facility and reduce the cost of wastewater treatment.

The treated water whose temperature has decreased while passing through the heat exchanger 120 is injected into the pH adjusting tank 130. A pH sensor (not shown) may be installed in the pH control tank 130. An appropriate pH adjusting agent is introduced into the pH adjusting tank 130 so that the pH measured by the pH sensor maintains a suitable range for subsequent treatment processes. The pH adjusting agent may be a hydroxide such as NaOH, KOH, Ca(OH) ₂ and various chemicals such as Na ₂ CO ₃ and CaO.

The shading reaction tank 140 is installed downstream of the pH control tank 130. Sodium hypochlorite (NaOCl) is introduced into the hypochlorite reactor 140, and the separated ammonia nitrogen (NH ₃ -N) contained in the treated water is nitrogen gas (N ₂ ) using sodium hypochlorite (NaOCl). ) Can oxidize a significant portion (approximately 80-90%).

An electrolysis tank 150 is installed downstream of the flame retardation tank 140. The electrolysis tank 140 almost completely removes a small amount (approximately 5 to 20%) of ammonia nitrogen (NH ₃ -N) remaining in the treated water that has undergone the nitrogen oxidation reaction in the primary salt reaction tank 140 almost completely. _It oxidizes with ₂ ) and oxidizes some COD. That is, a small amount of ammonia-nitrogen (NH ₃ -N) remains after the nitrogen oxidation reaction in the primary salt reaction tank 140, and the electrolysis tank 150 reacts in the secondary salt reaction tank 140 and remains in the treated water. chloride ion (Cl ^-) to reproduce the sodium hypochlorite (NaOCl) by the electrolytic action. Therefore, it is possible to treat a small amount of remaining ammonia nitrogen (NH ₃ -N) below the target water quality by performing a nitrogen oxidation reaction second using regenerated sodium hypochlorite (NaOCl).

In this way, as it is primarily treated with sodium hypochlorite and the second electrolysis reaction is performed, it is possible to treat wastewater without supplying additional chlorine ions.

The electrolysis tank 150 has a configuration in which the positive electrode 153 and the negative electrode 154 are disposed inside the decomposition tank body 151. The anode 153 has a configuration formed by coating at least one selected from platinum (Pt), iridium (Ir), ruthenium (Ru), tantalum (Ta), tin (Sn), and boron-diamond type. The cathode 154 has the same material and configuration as the anode 153, or has a configuration formed by coating one or more selected from titanium (Ti), graphite, lead (Pb), and zirconium (Zr) on a conductive base material. Can.

In addition, the shape of the surface of the positive electrode 153 and the negative electrode 154 is preferably a mesh type, a pipe type, or a flat type electrode, and the positive electrode 153 and the negative electrode The interval between 154 is preferably 1 to 5 mm.

However, the present invention is not limited thereto, and any electrode that can form hypochlorous acid by electrolysis of chlorine ions and an electrolytic cell having a structure, shape, and structure of electrodes can be applied.

The treated water in which ammonia nitrogen (NH ₃ -N) is removed from the electrolysis tank 150 (20 mg/L or less based on TN) is supplied to the neutralization means 160. The neutralizing means can be supplied to the processing unit 160 has a chlorate ion residual chlorine component remaining after the reaction of nitric oxide and neutralized to a ^reduction-a (HOCl, OCl and so on) of chloride ion (Cl) is harmless to the human body. To this end, various methods may be applied to the neutralizing means 160. Representative neutralization means 160 is a method of neutralizing through a chemical reaction using a chemical agent. At this time, the chemicals used are SO ₂ , Na ₂ SO ₃ , NaHSO ₃ , Na ₂ S ₂ O ₅ , Na ₂ S ₂ O ₃ , CaS ₂ O ₃ , (NH ₄ ) ₂ S ₂ O _3, etc. Typical compounds include inorganic dechlorinated compounds such as H ₂ S, iron compounds, and manganese compounds, or hydrogen peroxide.

In addition, another neutralization means 160 includes an adsorption method for adsorbing and treating residual chlorine components, such as activated carbon, and a catalyst reduction method using a catalyst in the form of a metal oxide or hydroxide.

In the neutralization means 160, residual chlorine in the wastewater can be removed by treating residual chlorine by combining one or more of the various neutralization methods described above.

In addition, the treated water discharged by being neutralized by the neutralizing means 160 may be used to directly generate electric energy while passing through the reverse electrodialysis power generation device (RED; 170).

Reverse electrodialysis power generation device (RED; 170), as shown in Figure 4, the oxidation electrode 171 and the cathode 172 are installed to face each other, the cation exchange membrane 173 between them (171,172) And an anion exchange membrane 174 are alternately stacked and arranged. The cation exchange membrane 173 and the anion exchange membrane 174 may form a unit cell including one fresh water flow path 175 and a brine flow path 176, and a plurality of unit cells may be stacked.

Here, the oxidation electrode 171 and the reduction electrode 172 may include a bipolar electrode or a monopolar electrode. In addition, spacers may be installed in each of the fresh water flow passage 175 and the brine flow passage 176, as well as the reduction flow passage and the oxidation flow passage.

A method of treating wastewater using the complex wastewater treatment system 100 according to an embodiment of the present invention having the above configuration will be described in detail.

1 to 4, the composite wastewater treatment method according to an embodiment of the present invention includes a carbon oxidation step (S10), a pH adjustment step (S20), a nitrogen oxidation step (S30), and a neutralization step (S40). .

Here, a concentration step (S100) may be further provided before the carbon oxidation step (S10).

In the concentration step (S100), concentrated water is classified by using concentrated means such as RO, NF, EDR, and CDI for raw waste water or pre-treated water except for high concentration raw waste water (CPP High), and then sorted concentrated water. It is supplied to the carbon oxidation step (S10) and the permeate is discharged. For example, after the intermediate concentration raw waste water (CPP Mid) is pre-treated through a simple filtration filter, it is directly supplied to the concentrate unit 101 to which RO is applied, and is separated into concentrated water and permeated water. S10) is supplied to proceed, the permeate is again separated into concentrated water and permeate through an RO filtration process installed over two stages, and the concentrated water generated again is supplied to the above step (S10).

And low concentration raw waste water (CPP Low), water treatment system, waste water (including chemical waste water) from the steam generator, oil waste water, etc., are supplied to the concentration unit 101 to proceed to the concentration step (S100) after passing through the pre-treatment process. do. Here, the pretreatment process may include a mixing process of various wastewaters, a chemical treatment process, a stirring process, a purification process (including sludge cake, pressure filter, ACF process), etc., which are generally known. That is, the treated waste water remaining after pre-treatment of low-concentration raw waste water as described above may be discharged or used to produce electrical energy through a reverse electrodialysis power generation apparatus. Then, the treated and remaining wastewater is supplied to the concentration unit 101 and pre-treated with medium-concentrated raw wastewater (CPP Mid), mixed with the sorted pre-treatment wastewater, and then subjected to a concentration process including RO filtration over 1 and 2 stages. , The concentrated water generated in this process is supplied to the step (S10). And the permeate is reused.

Here, as described above, the criteria for classifying raw waste water into high concentration, medium concentration, and low concentration can be classified by setting a reference range by COD, TN, etc., and each treatment process is differently selected and processed according to the set reference range. Can.

On the other hand, in the carbon oxidation step (S10), persulfate is introduced into the raw wastewater in the persulfuric acid reaction tank 110 to oxidize the COD component caused by ETA contained in the raw wastewater to CO ₂ , and TN to ammonia nitrogen ( NH ₃ -N) and a peroxidation reaction step (S11) and a heat exchange step (S13) to perform a heat exchange process between the treated and raw waste water treated by reacting in the persulfuric acid reaction tank 110.

In the step (S11), the persulfate input to the persulfate reaction tank 110 is preferably 1 to 30 wt% of liquid sodium persulfate (Na ₂ S ₂ O ₈ ) or liquid potassium persulfate (K ₂ S ₂ O ₈ ). Do.

In the step (S13), by heat-exchanging the treated water and raw waste water treated in the persulfate reaction tank 110, the temperature of the treated water is lowered to 35 to 45°C, and the temperature of the raw waste water is raised to 45 to 70°C. Therefore, the raw wastewater heated in the step (S13) can be quickly raised to the persulfuric acid reaction temperature (60 to 90°C) in the persulfuric acid reaction tank 110 to shorten the wastewater treatment process time.

In addition, in the step (S11), it is preferable to further include a catalytic reaction step (S15) in which a persulfate is introduced and a catalytic reaction is performed so that the persulfate generates a sulfate group.

In the step (S15), as described above, the temperature of the wastewater inside the persulfuric acid reaction tank 110 may be heated to a persulfuric acid reaction temperature (60 to 90°C) using the heater 111. In addition, as another method, the catalytic reaction may be caused by irradiating ultraviolet rays having a wavelength of 180 to 280 nm with the persulfate reaction tank 110 using the ultraviolet irradiator 113.

The raw waste water is treated with persulfate to oxidize the COD component caused by ETA to CO ₂ , and after TN is separated into ammonia nitrogen (NH ₃ -N), the pH of the treated wastewater is adjusted to the treatment standard. The pH adjusting agent is introduced from the pH adjusting tank 130 to be a suitable reference pH (6 to 8). The pH adjusting agent may be a hydroxide such as NaOH, KOH, Ca(OH) ₂ and various chemicals such as Na ₂ CO ₃ and CaO (S20).

Next, the ammonia nitrogen (NH ₃ -N) generated in the treated water in the step (S10) is oxidized and removed with nitrogen gas (N ₂ ) (S30).

More specifically, the step (S30) comprises a first step of nitrogen oxidation (S31) for oxidizing ammonia nitrogen (NH ₃ -N) first, and a second step of nitrogen oxidation (S33) for second oxidation.

In the step (S31), after receiving the treated wastewater in the decontamination tank 140, sodium hypochlorite (NaOCl) is added to a significant portion of the ammonia nitrogen (NH ₃ -N) through the desalting reaction (approximately 80 to 90) %) is oxidized with nitrogen gas (N ₂ ). In the step (S31), the concentration of sodium hypochlorite (NaOCl) input to the hypochlorite reactor 140 is 0.1 to 15% as Wt%, and the injection amount is preferably 3.0 to 10.0 kg NaOCl per 1 kg of nitrogen load.

Here, the sodium hypochlorite (NaOCl) input to the anti-salt reaction tank 140 may be supplied by electrolysis of seawater or brine.

A small amount (approximately 5-10%) of ammonia nitrogen (N ₂ ) remains in the treated water after the step (S31), which can be completely removed through the nitrogen oxidation step 2 (S33). That is, in the above step (S33), the treated water that has undergone the nitrogen oxidation reaction in the primary salt reaction tank 140 is supplied to the electrolysis tank 150, and the electrolysis tank 150 is microscopically (approximately). 5-20%) All remaining ammonia nitrogen (NH ₃ -N) is oxidized and removed with nitrogen gas (N ₂ ). That is, the reaction and the residual chlorine ion (Cl ^-) in the above step (S31) is to reproduce the sodium hypochlorite (NaOCl) by the electrolytic reaction in the electrolytic bath 150, and thus reproduce the same procedure as set forth in The remaining ammonia nitrogen (NH ₃ -N) by (NaOCl) is treated below the target water quality.

The current applied to the electrolysis tank 150 in the step (S33) is preferably a current density of 0.05 ~ 0.30A / ㎠.

The treated water in which the ammonia nitrogen (NaOCl) is completely removed in the step (S33) is supplied to the neutralization means 160, and after the nitrogen oxidation reaction, residual chlorine (HOCl, OCl ^-, etc.) harmless chlorine ions (Cl ^-The process of neutralization is performed (S40). The representative neutralization means 160 is a method of neutralizing through a chemical reaction using chemicals. At this time, the chemicals used are SO ₂ , Na ₂ SO ₃ , NaHSO ₃ , Na ₂ S ₂ O ₅ , Na ₂ S ₂ O ₃ , CaS ₂ O ₃ , (NH ₄ ) ₂ S ₂ O _3, etc. Typical compounds include inorganic dechlorinated compounds such as H ₂ S, iron compounds, and manganese compounds, or hydrogen peroxide.

In addition, other neutralization means 160 and 260 include an adsorption method for adsorbing and treating residual chlorine components, such as activated carbon, and a catalytic reduction method using a catalyst in the form of a metal oxide or hydroxide.

In the neutralization means 160, 260, one or more of these neutralization methods are combined to reduce residual chlorine and treat it to remove toxic substances remaining in the wastewater.

The treated water that has undergone the neutralization process as described above may be discharged in a state in which harmful substances are removed, and is also supplied to the reverse electrodialysis power generation device 170 as in the embodiment of the present invention to produce electrical energy (S50) ).

Meanwhile, the persulfate input to the persulfate reaction tank 110 in the step S11 may be produced and supplied by the persulfate production means 180, as described above. That is, in the persulfuric acid production step, it is briefly described as producing sodium persulfate or potassium persulfate using ammonia gas degassed in the pretreatment process of the raw waste water.

That is, in the persulfuric acid production step, after supplying the degassed ammonia to the scrubber 181, a sulfuric acid solution diluted to 5 to 50 wt. is injected, and recovered in the form of ammonium sulfate concentrated to 5 to 45 wt. The solution containing ions is supplied to an electrochemical conversion means 182 composed of a diaphragm-type electrolysis tank having an ion exchange membrane to produce ammonium persulfate, and then caustic soda is supplied to the chemical reaction tank 183 supplied with the ammonium persulfate produced. Potassium hydroxide is added to produce sodium persulfate or potassium persulfate. The produced persulfate can be stored in a storage tank 184 and supplied to the step S11 if necessary. The ammonia gas may be variously configured in the pretreatment step of the wastewater to be degassed, and the detailed description has been previously described, so further detailed description is omitted.

In addition, Figure 5 is a chlorine ion (Cl ^-) in a schematic configuration shown represents the composite wastewater treatment system 100 'according to another embodiment of the present invention, can be specifically concentrated wastewater or the pre-treatment, if present in a large amount is It shows the complex processing system applicable to. 6 is a process diagram for explaining a composite wastewater treatment method using the composite wastewater treatment system 100' shown in FIG.

In FIG. 5, the same reference numerals are assigned to the same components as those described in FIG. 1.

In consideration of this, referring to FIG. 5, the complex wastewater treatment system 100 ′ according to another embodiment of the present invention electrolyzes the treated water that has undergone the carbon oxidation process in the persulfuric acid reaction tank 110 and the pH It has a technical feature to have a configuration capable of completely oxidizing the ammonia nitrogen (NH ₃ -N) contained in the treated water with nitrogen gas (N ₂ ) while repeatedly circulating between the control tanks 130. To this end, the complex wastewater treatment system 100' includes a circulation path 171 for circulating the treated water of the electrolysis tank 150 to the pH adjustment tank 130, and a circulation pump 173 installed in the circulation path 171 ).

With such a configuration, and the sulfuric acid treatment electrolyzer 150 and pH adjustment tank, while repeatedly circulating between 130 chloride ion (Cl ^-), the remaining ammonia in the treated water to produce converted into sodium hypochlorite (NaOCl) Free nitrogen (NH ₃ -N) can be completely oxidized with nitrogen gas (N ₂ ).

At this time, chlorine ion (Cl ^-) in the waste water when running out of components, the chloride ion (Cl ^-) via a separate supply may be configured to additionally supply.

A method of treating the composite wastewater using the composite wastewater treatment system 100' shown in FIG. 5 will be described with reference to FIG. 6 as follows.

Referring to Figure 6, the complex wastewater treatment method according to another embodiment of the present invention, the concentration step (S100), carbon oxidation step (S10), pH adjustment step (S20), nitrogen oxidation step (S30'), neutralization step (S40) and reverse electrodialysis power generation step (S50). In FIG. 6, the same reference numerals are assigned to the same processes as the wastewater treatment process described through FIGS. 2 and 3, and detailed description thereof will be omitted.

The concentration step (S100), as previously described with reference to FIG. 3, the concentrated filtration process of RO, NF, EDR, CDI, etc. for the pre-treated wastewater obtained after each pre-treatment process for the sorted wastewater according to the concentration of the raw waste water. Through the concentrated fractionation, or concentrated raw waste water of a medium concentration through the concentrated fractionation process, the concentrated water is supplied to the carbon oxidation step (S10).

Of course, high-concentration raw waste water is supplied to the carbon oxidation step (S10) without going through a concentration step.

Convert the sodium hypochlorite (NaOCl) ^-, while the treated repeatedly cycle through the electrolyzer 150 and the pH adjustment tank 130, chloride ion (Cl) as described above in the nitrogen oxide step (S30 ') Ammonia nitrogen (NH ₃ -N) remaining in the treated water after production is oxidized with nitrogen gas (N2) to be processed below the target water quality standard.

As described above, according to the complex wastewater treatment system and treatment method of the present invention, the wastewater of a secondary system water such as a nuclear power plant is sequentially caused by ETA contained in wastewater while sequentially undergoing a carbon oxidation process and a nitrogen oxidation process. By removing COD by oxidizing with CO ₂ and completely removing TN, nuclear power plants can be operated stably and efficiently. In particular, conventionally, COD caused by ETA that does not decompose even after physicochemical treatment and advanced oxidation treatment (electrolysis) can be completely treated.

In particular, by setting and treating the treatment process differently according to the concentration of the raw waste water, it is possible to effectively treat the waste water, and it has an advantage of shortening the treatment time and increasing efficiency.

Above, the present invention has been shown and described in connection with a preferred embodiment for illustrating the principles of the present invention, but the present invention is not limited to the configuration and operation as shown and described. Rather, those skilled in the art will appreciate that many changes and modifications to the present invention are possible without departing from the spirit and scope of the appended claims.

100,100..complex wastewater treatment system
101..RO filtration unit 110..Persulfuric acid reaction tank
111.. Heater 113.. UV generator
120..heat exchanger 130..pH control tank
140..Salt reaction tank 150..Electrolysis tank
160,260..Chinese means 171..Circulation path
173..Circulation pump 180..Persulfate production means

Claims (13)

To treat wastewater containing both COD-causing and TN-causing substances in a single component,
A persulfate reaction tank for oxidizing the COD-inducing component contained in the wastewater to CO ₂ using persulfate and separating TN into ammonia nitrogen (NH ₃ -N);
A _secondary salt reaction tank for oxidizing the separated nitrogen treated and treated in the persulfuric acid reactor with nitrogen gas (N ₂ ) using sodium hypochlorite (NaOCl);
Oxidizing the ammonium nitrogen (NH ₃ -N) and COD components is some residual untreated to produce converted into sodium hypochlorite (NaOCl) by ^{electrolysis-chloride} ion (Cl) remaining in the treated water treated in the reaction tank chayeom Electrolysis tank; And
It is installed in the persulfate reaction tank, the persulfate is mixed while the persulfate catalyst device to generate a sulfate group; includes,
The catalyst device is a complex wastewater treatment system, characterized in that it comprises a heater installed to heat the interior of the persulfuric acid reaction tank in the range of 60 to 90 ℃. To treat wastewater containing both COD-causing and TN-causing substances in a single component,
A persulfate reaction tank for oxidizing the COD-inducing component contained in the wastewater to CO ₂ using persulfate and separating TN into ammonia nitrogen (NH ₃ -N);
The conversion produces separated by sodium hypochlorite (NaOCl) ammonium nitrogen (NH ₃ -N), nitrogen gas ^(wherein the chlorine ions (Cl) containing the water treatment process in a sulfuric acid tank to be treated by electrolysis An electrolysis tank oxidizing with N ₂ ) and oxidizing the remaining COD components; And
It is installed in the persulfate reaction tank, the persulfate is mixed while the persulfate catalyst device to generate a sulfate group; includes,
The catalyst device is a complex wastewater treatment system, characterized in that it comprises a heater installed to heat the interior of the persulfuric acid reaction tank in the range of 60 to 90 ℃. To treat wastewater containing both COD-causing and TN-causing substances in a single component,
A persulfate reaction tank for oxidizing the COD-inducing component contained in the wastewater to CO ₂ using persulfate and separating TN into ammonia nitrogen (NH ₃ -N);
A _secondary salt reaction tank for oxidizing the separated nitrogen treated and treated in the persulfuric acid reactor with nitrogen gas (N ₂ ) using sodium hypochlorite (NaOCl); And
Oxidizing the ammonium nitrogen (NH ₃ -N) and COD components is some residual untreated to produce converted into sodium hypochlorite (NaOCl) by ^{electrolysis-chloride} ion (Cl) remaining in the treated water treated in the reaction tank chayeom The electrolysis tank to be included;
A complex wastewater treatment system characterized in that the persulfate inputted to the persulfate reaction tank is 1 to 30 wt% of liquid potassium persulfate (K ₂ S ₂ O ₈ ). To treat wastewater containing both COD-causing and TN-causing substances in a single component,
A persulfate reaction tank for oxidizing the COD-inducing component contained in the wastewater to CO ₂ using persulfate and separating TN into ammonia nitrogen (NH ₃ -N); And
The conversion produces separated by sodium hypochlorite (NaOCl) ammonium nitrogen (NH ₃ -N), nitrogen gas ^(wherein the chlorine ions (Cl) containing the water treatment process in a sulfuric acid tank to be treated by electrolysis N ₂ ) and oxidizes the remaining COD components while oxidizing;
A complex wastewater treatment system characterized in that the persulfate inputted to the persulfate reaction tank is 1 to 30 wt% of liquid potassium persulfate (K ₂ S ₂ O ₈ ). To treat wastewater containing both COD-causing and TN-causing substances in a single component,
A persulfate reaction tank for oxidizing the COD-inducing component contained in the wastewater to CO ₂ using persulfate and separating TN into ammonia nitrogen (NH ₃ -N);
A _secondary salt reaction tank for oxidizing the separated nitrogen treated and treated in the persulfuric acid reactor with nitrogen gas (N ₂ ) using sodium hypochlorite (NaOCl);
Oxidizing the ammonium nitrogen (NH ₃ -N) and COD components is some residual untreated to produce converted into sodium hypochlorite (NaOCl) by ^{electrolysis-chloride} ion (Cl) remaining in the treated water treated in the reaction tank chayeom Electrolysis tank; And
Including the heat exchanger to circulate the treated water treated by persulfuric acid reaction in the persulfuric acid reaction tank to increase the temperature of the concentrated water or raw waste water input to the persulfuric acid reaction tank, and to lower the temperature of the persulfate-reacted treated water; ,
The treated water treated by persulfuric acid reaction in the persulfuric acid reaction tank increases the temperature of the wastewater in the wastewater supply line to a temperature of 45 to 70°C while passing through the heat exchanger, and the treated water reacted with persulfuric acid to 35 to 45°C. Complex wastewater treatment system characterized in that it can be lowered. To treat wastewater containing both COD-causing and TN-causing substances in a single component,
A persulfate reaction tank for oxidizing the COD-inducing component contained in the wastewater to CO ₂ using persulfate and separating TN into ammonia nitrogen (NH ₃ -N);
The conversion produces separated by sodium hypochlorite (NaOCl) ammonium nitrogen (NH ₃ -N), nitrogen gas ^(wherein the chlorine ions (Cl) containing the water treatment process in a sulfuric acid tank to be treated by electrolysis An electrolysis tank oxidizing with N ₂ ) and oxidizing the remaining COD components; And
Including the heat exchanger to circulate the treated water treated by persulfuric acid reaction in the persulfuric acid reaction tank to increase the temperature of the concentrated water or raw waste water input to the persulfuric acid reaction tank, and to lower the temperature of the persulfate-reacted treated water; ,
The treated water treated by persulfuric acid reaction in the persulfuric acid reaction tank increases the temperature of the wastewater in the wastewater supply line to a temperature of 45 to 70°C while passing through the heat exchanger, and the treated water reacted with persulfuric acid to 35 to 45°C. Complex wastewater treatment system characterized in that it can be lowered. In the method of treating wastewater generated from the secondary system generated waste water of a power plant, a nuclear power plant, a water treatment system of a multiple desalination facility, and simultaneously containing a COD inducer and a TN inducer in a single component,
Persulfate is injected into a persulfate reaction tank containing concentrated or raw wastewater in which wastewater is concentrated to oxidize the COD component contained in the concentrated or raw wastewater to CO ₂ and at the same time TN to ammonia nitrogen (NH ₃ -N) Carbon oxidation step to separate into;
A first step of nitrogen oxidation in which the ammonia nitrogen separated in the carbon oxidation step is first oxidized with nitrogen gas (N ₂ ) using sodium hypochlorite (NaOCl);
The chloride ion (Cl ^-) remaining in the treated water from the reaction of nitric oxide Step 1 to the reproduction by the sodium hypochlorite (NaOCl) through the electrolyzer remaining ammonia nitrogen on the number of the processing (NH ₃ -N) nitrogen A second step of oxidizing nitrogen with a gas (N ₂ ) and simultaneously oxidizing some remaining COD components; And
It includes a catalytic reaction step of using a catalytic device installed in the persulfuric acid reaction tank to produce a sulfate group at the same time as the persulfate is mixed into the persulfuric acid reaction tank:
The catalyst device,
And a heater installed to heat the persulfuric acid reaction tank in a range of 60 to 90°C. In the method of treating wastewater generated from the secondary system generated waste water of a power plant, a nuclear power plant, a water treatment system of a multiple desalination facility, and simultaneously containing a COD inducer and a TN inducer in a single component,
Persulfate is injected into a persulfate reaction tank containing concentrated or raw wastewater in which wastewater is concentrated to oxidize the COD component contained in the concentrated or raw wastewater to CO ₂ and at the same time TN to ammonia nitrogen (NH ₃ -N) Carbon oxidation step to separate into;
A chloride ion (Cl ^-) contained in the number of treatment processes in the carbon oxidation step ^- can the process produce convert the sodium hypochlorite (NaOCl) for circulating twos electrolysis with chlorine ions (Cl) contained in the number of the processing Nitrogen oxidation step of oxidizing the ammonia nitrogen (NH ₃ -N) contained in nitrogen gas (N ₂ ) and oxidizes some of the remaining COD components; And
It includes a catalytic reaction step of using a catalytic device installed in the persulfuric acid reaction tank to produce a sulfate group at the same time as the persulfate is mixed into the persulfuric acid reaction tank:
The catalyst device,
And a heater installed to heat the persulfuric acid reaction tank in a range of 60 to 90°C. In the method of treating wastewater generated from the secondary system generated waste water of a power plant, a nuclear power plant, a water treatment system of a multiple desalination facility, and simultaneously containing a COD inducer and a TN inducer in a single component,
Persulfate is injected into a persulfate reaction tank containing concentrated or raw wastewater in which wastewater is concentrated to oxidize the COD component contained in the concentrated or raw wastewater to CO ₂ and at the same time TN to ammonia nitrogen (NH ₃ -N) Carbon oxidation step to separate into;
A first step of nitrogen oxidation in which the ammonia nitrogen separated in the carbon oxidation step is first oxidized with nitrogen gas (N ₂ ) using sodium hypochlorite (NaOCl); And
The chloride ion (Cl ^-) remaining in the treated water from the reaction of nitric oxide Step 1 to the reproduction by the sodium hypochlorite (NaOCl) through the electrolyzer remaining ammonia nitrogen on the number of the processing (NH ₃ -N) nitrogen It includes a second step of nitrogen oxidation to oxidize a portion of the remaining COD while simultaneously oxidizing it with gas (N ₂ ).
The persulfate injected in the carbon oxidation step is a composite wastewater treatment method characterized in that the liquid potassium persulfate (K ₂ S ₂ O ₈ ) of 1 to 30 wt%. In the method of treating wastewater generated from the secondary system generated waste water of a power plant, a nuclear power plant, a water treatment system of a multiple desalination facility, and simultaneously containing a COD inducer and a TN inducer in a single component,
Persulfate is injected into a persulfate reaction tank containing concentrated or raw wastewater in which wastewater is concentrated to oxidize the COD component contained in the concentrated or raw wastewater to CO ₂ and at the same time TN to ammonia nitrogen (NH ₃ -N) Carbon oxidation step to separate into; And
A chloride ion (Cl ^-) contained in the number of treatment processes in the carbon oxidation step ^- can the process produce convert the sodium hypochlorite (NaOCl) for circulating twos electrolysis with chlorine ions (Cl) contained in the number of the processing Includes a nitrogen oxidation step of oxidizing the ammonia nitrogen (NH ₃ -N) contained in nitrogen gas (N ₂ ) and oxidizes some of the remaining COD components.
The persulfate injected in the carbon oxidation step is a composite wastewater treatment method characterized in that the liquid potassium persulfate (K ₂ S ₂ O ₈ ) of 1 to 30 wt%. In the method of treating wastewater generated from the secondary system generated waste water of a power plant, a nuclear power plant, a water treatment system of a multiple desalination facility, and simultaneously containing a COD inducer and a TN inducer in a single component,
Persulfate is injected into a persulfate reaction tank containing concentrated or raw wastewater in which wastewater is concentrated to oxidize the COD component contained in the concentrated or raw wastewater to CO ₂ and at the same time TN to ammonia nitrogen (NH ₃ -N) Carbon oxidation step to separate into;
A first step of nitrogen oxidation in which the ammonia nitrogen separated in the carbon oxidation step is first oxidized with nitrogen gas (N ₂ ) using sodium hypochlorite (NaOCl);
The chloride ion (Cl ^-) remaining in the treated water from the reaction of nitric oxide Step 1 to the reproduction by the sodium hypochlorite (NaOCl) through the electrolyzer remaining ammonia nitrogen on the number of the processing (NH ₃ -N) nitrogen A second step of oxidizing nitrogen with a gas (N ₂ ) and simultaneously oxidizing some remaining COD components; And
It includes; heat exchange step of circulating the treated water that has undergone the carbon oxidation step to a heat exchanger to increase the temperature of the concentrated or high concentration raw wastewater flowing into the heat exchanger and lowering the temperature of the treated water in the persulfuric acid reaction tank;
The treated water treated by persulfuric acid reaction in the persulfuric acid reaction tank increases the temperature of the wastewater in the wastewater supply line to a temperature of 45 to 70°C while passing through the heat exchanger, and the treated water reacted with persulfuric acid to 35 to 45°C. Complex wastewater treatment method characterized in that it can be lowered. In the method of treating wastewater generated from the secondary system generated waste water of a power plant, a nuclear power plant, a water treatment system of a multiple desalination facility, and simultaneously containing a COD inducer and a TN inducer in a single component,
Persulfate is injected into a persulfate reaction tank containing concentrated or raw wastewater in which wastewater is concentrated to oxidize the COD component contained in the concentrated or raw wastewater to CO ₂ and at the same time TN to ammonia nitrogen (NH ₃ -N) Carbon oxidation step to separate into;
A chloride ion (Cl ^-) contained in the number of treatment processes in the carbon oxidation step ^- can the process produce convert the sodium hypochlorite (NaOCl) for circulating twos electrolysis with chlorine ions (Cl) contained in the number of the processing Nitrogen oxidation step of oxidizing the ammonia nitrogen (NH ₃ -N) contained in nitrogen gas (N ₂ ) and oxidizes some of the remaining COD components; And
It includes; heat exchange step of circulating the treated water that has undergone the carbon oxidation step to a heat exchanger to increase the temperature of the concentrated or high concentration raw wastewater flowing into the heat exchanger and lowering the temperature of the treated water in the persulfuric acid reaction tank;
The treated water treated by persulfuric acid reaction in the persulfuric acid reaction tank increases the temperature of the wastewater in the wastewater supply line to a temperature of 45 to 70°C while passing through the heat exchanger, and the treated water reacted with persulfuric acid to 35 to 45°C. Complex wastewater treatment method characterized in that it can be lowered. The method of claim 11,
The concentration of the sodium hypochlorite input to the carbohydrate reaction tank in the nitrogen oxidation step 1 is 0.1 to 15% by weight, and the injection amount is 3.0 to 10.0kg NaOCl per kg of nitrogen load.

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