KR102525217B1 - Non-degradable Waste Water Treatment System - Google Patents

Abstract

The present invention is a system for treating wastewater containing non-decomposable contaminants: an oxidation water treatment device (20) for decomposing non-decomposable substances of NS bonds by adding metal oxidized water to the wastewater; an ultraviolet treatment device 30 connected to a downstream side of the oxidation water treatment device 20 and irradiating ultraviolet rays; and an electrooxidation processor 40 connected to a downstream side of the UV treatment device 30 and causing adsorption and oxidation of contaminants.
Accordingly, in removing COD organic matter that is difficult to decompose by microorganisms in various wastewater, maintenance is required to a minimum based on the flexibility of the process, which has the effect of saving labor and reducing operating costs.

Description

Non-degradable Waste Water Treatment System}

The present invention relates to a wastewater treatment system, and more particularly, to a non-degradable wastewater treatment system for removing COD organic matter that is difficult to be decomposed by microorganisms in various wastewater.

In general, various types of wastewater, including industrial wastewater, have various compositions depending on the source, and sometimes contain COD organic matter or toxic substances, which causes difficulties in biological treatment. In particular, non-biodegradable wastewater generated from thermal power plants, dyeing/plating/leather companies, and livestock farms has low efficiency and safety due to complex treatment processes, and relatively high operating costs are a burden.

As related prior art documents, Korean Patent Registration No. 0251405 (Prior Document 1), Korean Utility Model Registration No. 0461827 (Prior Document 2), and Korean Patent Registration No. 1026641 (Prior Document 3) are known. .

Prior Document 1 converts hydroxide ions (OH-) obtained through electrolysis of water into hydroxyl radicals (-OH Radical) through a titanium dioxide (TiO ₂ ) photocatalyst to remove toxic and recalcitrant organic substances and use an electrode. It is configured to adsorb and remove heavy metal ions contained in wastewater.

Prior Document 2 is a step of sterilizing oxidants and organic substances by ozone while dissolving and supplying ozone to wastewater, a step of treating dioxin and residual organic substances by oxidation by injecting hydrogen peroxide (H ₂ O ₂ ), and an electrode plate Sterilization by electrolysis and treatment steps by redox action are repeatedly performed.

Prior Document 3 is an air supplier for dissolving oxygen in organic wastewater into which electrolyte is introduced; A non-diaphragm electrolyzer in which organic wastewater is introduced to oxidize divalent iron from an electrolyte, generate free chlorine, and generate hydrogen peroxide to induce a Fenton oxidation reaction; UV photoreactor irradiating UV to the oxidized wastewater; Include etc.

However, according to the above prior literature, since periodic maintenance is required, there is room for improvement in terms of saving labor and reducing operating costs.

Korean Registered Patent Publication No. 0251405 "Waste water treatment device using electrolysis and photocatalyst" (Publication date: 1999.04.06.) Korean Registered Utility Model Publication No. 0461827 "Waste water treatment device containing non-degradable harmful substances" (published date: 2011.11.09.) Korean Registered Patent Publication No. 1026641 "Electrolysis and photo-Fenton oxidation process combined... Apparatus and method for treating non-degradable wastewater" (Publication date: 2010.01.11.)

The object of the present invention for improving the above conventional problems is, in removing COD organic matter that is difficult to be decomposed by microorganisms in various wastewater, based on the flexibility of the process, maintenance is required to a minimum, and it is difficult to decompose To provide a wastewater treatment system.

Another object of the present invention is to provide a non-degradable wastewater treatment system having an eco-friendliness that excludes a post-treatment process such as injection of a reducing agent because metal oxide water is completely reduced and does not remain after UV reaction of wastewater.

In order to achieve the above object, the present invention provides a system for treating wastewater containing non-decomposable pollutants: an oxidation water treatment device that decomposes non-decomposable substances of N-S bonds by adding metal oxidized water to the wastewater; an ultraviolet treatment device connected to the downstream side of the oxidation water treatment device and irradiating ultraviolet rays; and an electrooxidation processor connected to a downstream side of the UV treatment device and causing adsorption and oxidation of contaminants.

As a detailed configuration of the present invention, the oxidation water treatment device is provided with a ferrate supply unit for generating ferrate metal oxidation water, a CSTR for causing treatment based on a continuous stirred tank reactor, and a PFR for causing treatment based on a plug flow reactor. to be characterized

As a detailed configuration of the present invention, the oxidation water treatment device is characterized in that it is installed to change the inflow flow rate of the upstream side and the discharge flow rate of the downstream side.

As a detailed configuration of the present invention, the ultraviolet treatment device includes a UV lamp installed in the flow direction, a reflector plate installed to face the UV lamp, a PUV lamp installed in a direction perpendicular to the flow, and a reflective plate installed to face the PUV lamp. It is characterized by providing.

At this time, the reflective curved plate is characterized in that it is installed in a corrugated shape to induce turbulent flow of wastewater.

As a detailed configuration of the present invention, the electrooxidizer is characterized by having an anode disposed in the center of the housing, a cathode disposed on the inner circumferential surface of the housing, and an absorbent accommodated in a space between the anode and the cathode.

At this time, the adsorbent is characterized in that it is formed to maintain a porosity of 50% or more by using graphite as a main component.

As described above, according to the present invention, in removing COD organic matter that is difficult to decompose by microorganisms in various wastewater, maintenance is required to a minimum based on the flexibility of the process, and thus there is an effect of saving labor and reducing operating costs.

1 is a schematic diagram showing the system according to the present invention as a whole
Figure 2 is a schematic diagram showing the ultraviolet treatment system of the system according to the present invention
Figure 3 is a schematic diagram showing the electrooxidation processor of the system according to the present invention
Figure 4 is a schematic diagram showing the main operation of the system according to the present invention

Hereinafter, embodiments of the present invention will be described in detail based on the accompanying drawings.

The present invention proposes a system for treating wastewater containing non-degradable pollutants. It is intended to treat non-degradable wastewater generated from thermal power plants, dyeing/plating/leather companies, and livestock farms, but is not necessarily limited thereto.

According to the present invention, the oxidation water treatment device 20 has a structure in which metal oxidation water is added to wastewater to decompose hardly decomposable substances of N-S bonds.

Referring to FIG. 1 , a state in which an oxidation water treatment device 20 is installed downstream of the inlet water tank 11 is shown. Desulfurization wastewater from thermal power plants contains non-decomposable compounds of NS bonds composed of S ₂ O ₆ ^2- components. In addition, non-degradable substances such as alkylsulfonate (AS), polychlorinated biphenyl (PCB), organic nitrile compounds, and polyethylene glycol are also targeted.

As a detailed configuration of the present invention, the oxidation water treatment device 20 includes a ferrate supply unit 22 that generates ferrate (VI) metal oxidized water, a CSTR 24 that causes treatment based on a continuous stirred tank reactor, and a plug flow reactor. It is characterized by having a PFR (26) that triggers processing based on.

In FIG. 1, a ferrate supply unit 22, a CSTR 24, and a PFR 26 constituting the oxidation water treatment device 20 are shown. In the ferrate supply unit 22, ferrate is produced by combining an alkali or alkaline earth metal with ferrate ions (FeO ₄ ^2- ). In water treatment reactions, strong oxidizing agents act as coagulants as well. CSTR (24) is a continuous stirred tank reactor (Continuous Stirred Tank Reactor) equipped with an agitator and connected to the downstream of the ferrate feeder (22). The PFR 26 is a plug flow reactor (PFR) in the form of a long tube and is connected downstream of the CSTR 24. The CSTR (24) has a rather low conversion rate of reaction, but it is easy to control the temperature, and the PFR (26) has a high conversion rate of reaction although it is difficult to control the temperature. In either case, the oxidation water treatment device 20 improves the removal rate of NS-COD, TN, SS, and TP.

Meanwhile, the CSTR (24) and the PFR (26) may have a UV lamp (31) inside the tank, and in this case, a multi-wavelength type UV lamp (31) is preferred.

As a detailed configuration of the present invention, the oxidation water treatment device 20 is characterized in that it is installed to change the inflow flow rate of the upstream side and the discharge flow rate of the downstream side.

In FIG. 1, a part of the wastewater from the inlet water tank 11 flows into the oxidation water treatment device 20 and the rest flows into the ultraviolet treatment device 30 to be described later. Depending on the physical properties of the wastewater in the inlet water tank 11, the flow rate flowing from the inlet water tank 11 to the oxidation water treatment device 20 varies. Part of the wastewater that has passed through the oxidation water treatment unit 20 is sent to the ultraviolet treatment unit 30 and the rest is sent to the electrooxidation unit 40. Depending on the physical properties of the wastewater, the flow rate sent from the oxidation water treatment device 20 to the ultraviolet treatment device 30 and the electrooxidation treatment device 40 varies. It can be controlled remotely by means of a pump 14 and a motorized valve 16 on the wastewater flow path.

In addition, according to the present invention, the ultraviolet treatment device 30 for irradiating ultraviolet rays forms a structure connected to the downstream side of the oxidation water treatment device 20.

Referring to FIGS. 1 and 2 , the ultraviolet treatment device 30 is a method of generating OH radicals by irradiating ultraviolet rays to oxidized water, which is an oxidizing agent, by UV photolysis. Hydroxy radicals have very strong oxidizing power and can also break the double bond of C=C. The UV treatment device 30 is controlled to irradiate UV with a wavelength of 100 to 400 mm to the oxidized wastewater. The low pressure/high output method is preferred in terms of extending the life while maintaining the sterilizing power to some extent.

As a detailed configuration of the present invention, the ultraviolet treatment device 30 includes a UV lamp 31 installed in a flow direction, a reflector plate 33 installed to face the UV lamp 31, and a PUV installed in a direction orthogonal to the flow. It is characterized by having a lamp 35 and a reflection plate 37 installed to face the PUV lamp 35.

In FIG. 2, a UV lamp 31, a reflective curved plate 33, a PUV lamp 35, and a reflective plate 37 constituting the ultraviolet treatment device 30 are shown. The ultraviolet treatment device 30 is formed in a substantially cylindrical shape and has an inlet and an outlet of wastewater vertically. The UV lamp 31 may maintain the same as that provided in the oxidation water treatment device 20 described above. The PUV lamp 35 is accommodated inside the quartz cell and irradiates pulsed ultraviolet rays having a wavelength of 180 to 280 nm. The UV lamps 31 are arranged vertically in the axial direction to coincide with the flow direction of wastewater, and the PUV lamps 35 are arranged horizontally in the radial direction adjacent to the inlet and outlet to prevent dead zones. The reflective curved plate 33 and the reflective flat plate 37 prevent a phenomenon in which the formation of OH radicals is low due to low transmittance when the turbidity or chromaticity of the wastewater is high, thereby lowering the treatment efficiency. The reflective curved plate 33 is formed in a curved (circular arc) structure to face the UV lamp 31, and the reflective flat plate 37 is formed in a flat (disc shape) structure to face the PUV lamp 35.

At this time, the reflective curved plate 33 is characterized in that it is installed in a corrugated shape to induce turbulent flow of wastewater.

Meanwhile, the UV treatment device 30 prefers an upflow method rather than a downflow method to increase the residence time of the wastewater, and may further include an impeller (not shown) approximately in the center to intensify the turbulent flow of the wastewater. .

2 shows a state in which the corrugated reflector plate 33 is installed on the cylindrical inner circumferential surface of the ultraviolet treatment device 30 . The corrugated reflector 33 has a form in which substantially circular or arc-shaped reflectors are alternately and obliquely connected to form a triangular cross section. The wastewater flowing up and down the ultraviolet treatment device 30 causes a turbulent flow while passing through the corrugated reflector plate 33, thereby increasing treatment efficiency by the UV lamp 31 and the PUV lamp 35.

In addition, according to the present invention, the electrooxidation treatment device 40 that causes the adsorption and oxidation of the contaminants is connected to the downstream side of the ultraviolet treatment device 30.

Referring to FIGS. 1 and 3 , a state in which the electrooxidizer 40 is configured in a substantially cylindrical housing 41 is shown. It is preferable to install the electrooxidation processor 40 through a plurality of housings 41 in view of process flexibility. In FIG. 1 , the electrooxidation processor 40 is divided into three housings 41, and wastewater sent from the ultraviolet treatment device 30 and wastewater sent to the oxidation water treatment device 20 are selectively treated. The electrooxidation treatment unit 40 is flexibly controlled in response to the physical properties of the wastewater in the inlet water tank 11.

As a detailed configuration of the present invention, the electrooxidizer 40 includes an anode 42 disposed in the center of the housing 41, a cathode 43 disposed on the inner circumferential surface of the housing 41, an anode 42 and a cathode ( 43) characterized in that it includes an adsorbent 45 accommodated in the space between them.

In FIG. 3, an anode 42, a cathode 43, an adsorbent 45, and the like constituting the electrooxidation apparatus 40 are shown. The central anode 42 is formed in a rod shape of stainless steel material, and the anode 42 on the inner circumferential surface is formed in a mesh shape of platinum material. The adsorbent 45 induces an electrical oxidation reaction between the anode 42 and the cathode 43 to act as a media adsorbing and removing contaminants (CM) from wastewater.

At this time, the adsorbent 45 is characterized in that it is formed to maintain a porosity of 50% or more by using graphite as a main component.

Referring to FIGS. 3 and 4 , a reaction mechanism in which the electrooxidation processor 40 removes contaminants (CM) by the mediation of the adsorbent 45 is shown. The adsorbent 45 has graphite as a main component and activated carbon or zeolite as a secondary component. In addition to graphite (activated carbon/zeolite), a resin auxiliary component may be further included to increase durability. When the adsorbent 45 made of graphite is filled with a porosity of 50% or more, it is possible to increase the adsorption/oxidation rate of contaminants (CM) while ensuring an appropriate treatment flow rate (speed). Since graphite is oxidized and regenerated as a medium at the same time in connection with current through the anode 42 and cathode 43, replacement is unnecessary, reducing operating costs to 1/10 compared to activated carbon. In the process of generating treated water by removing non-decomposable pollutants (CM) from high/low concentration wastewater, maintenance of the electrooxidation processor 40 is minimized, so it is possible to take a step forward in saving labor.

At this time, as shown in FIG. 3, the main component 45A and the subcomponent 45B of the adsorbent 45 may be disposed in different regions without mixing.

Meanwhile, treated water purified through the electrooxidation treatment unit 40 is collected in the treated water tank 12 and sent to a subsequent process.

In the case of conventional UV/H ₂ O _{2 (} or UV/O ₃ ) treatment, residual oxidants (H ₂ O ₂ or O ₃ ) remain even after UV oxidation, so a separate post-treatment process to remove these residual oxidants (Input of activated carbon or reducing agent) was required, but the present invention is more eco-friendly because the metal oxide water is completely reduced by the UV oxidation process and does not remain, so a separate post-treatment process is excluded or minimized.

The present invention is not limited to the described embodiments, and it is obvious to those skilled in the art that various modifications and variations can be made without departing from the spirit and scope of the present invention. Therefore, such variations or modifications should fall within the scope of the claims of the present invention.

11: inlet water tank 12: treated water tank
14: pump 16: valve
20: oxidation water treatment unit 22: ferrate supply unit
24: CSTR 26: PFR
30: UV treatment machine 31: UV lamp
33: reflective curved plate 35: PUV lamp
37: reflective plate 40: electrooxidation processor
41: housing 42: anode
43: cathode 45: absorbent
CM: contaminants

Claims (7)

In a system for treating wastewater containing recalcitrant pollutants:
An oxidation water treatment unit 20 that decomposes non-decomposable substances of NS bonds by adding metal oxidation water to wastewater;
an ultraviolet treatment device 30 connected to a downstream side of the oxidation water treatment device 20 and irradiating ultraviolet rays; and
An electrooxidation processor 40 connected to the downstream side of the ultraviolet treatment device 30 and causing adsorption and oxidation of contaminants,
The oxidation water treatment device 20 includes a ferrate supply unit 22 that generates ferrate (VI) metal oxidation water, a CSTR 24 that causes treatment based on a continuous stirred tank reactor, and a plug flow reactor that causes treatment based on Equipped with a PFR (26),
The oxidation water treatment device 20 is installed to change the inflow flow rate of the upstream side and the outgoing flow rate of the downstream side,
The ultraviolet treatment device 30 includes a UV lamp 31 installed in the flow direction, a reflector plate 33 installed to face the UV lamp 31, a PUV lamp 35 installed in a direction perpendicular to the flow, and a PUV lamp Equipped with a reflective plate 37 installed to face (35),
The reflective curved plate 33 is installed in a corrugated shape to induce turbulent flow of wastewater,
The electrooxidizer 40 accommodates an anode 42 disposed in the center of the housing 41, a cathode 43 disposed on the inner circumferential surface of the housing 41, and a space between the anode 42 and the cathode 43. A recalcitrant wastewater treatment system comprising an adsorbent (45). delete delete delete delete delete The method of claim 1,
The adsorbent 45 is a recalcitrant wastewater treatment system, characterized in that formed to maintain a porosity of 50% or more by using graphite as a main component.

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