Wastewater reuse treatment system using a rotary-driven pore-controlled fiber filter

Abstract

The present invention relates to a wastewater reuse treatment system that oxidizes non-biodegradable organic matter, color-causing substances, fine suspended solids, and microorganisms in wastewater using ozone-containing nanobubbles, stabilizes the fine oxidation flux formed during the oxidation process in a retention zone, performs high-efficiency filtration treatment through a rotary-driven pore-controlled fiber filter, and recirculates a portion of the treated water containing ozone-containing nanobubbles as backwash water for the fiber filter to improve the cleaning efficiency of the fiber filter media. Accordingly, the present invention comprises an ozone contact tank (110) for oxidizing discharge water; a nanobubble supply unit (120) for supplying ozone-containing nanobubbles to the ozone contact tank (110); a rotary drive type pore control type fiber filter (130) disposed at the rear end of the ozone contact tank (110); and a recirculation line (140) for supplying a portion of the treated water oxidized in the ozone contact tank (110) as backwash water to the rotary drive type pore control type fiber filter (130).

Description

Technology Field

[0001] The present invention relates to a wastewater reuse treatment system for utilizing wastewater from sewage treatment plants, wastewater treatment plants, industrial complexes, public sewage treatment facilities, or treated water subject to reuse by highly treating it for landscaping, washing, industrial, agricultural, or other non-potable reuse.

[0002] More specifically, the present invention relates to a wastewater reuse treatment system that oxidizes non-biodegradable organic matter, color-causing substances, fine suspended solids, and microorganisms in wastewater using ozone-containing nanobubbles, stabilizes the fine oxidation flux formed during the oxidation process in a retention zone, performs high-efficiency filtration treatment through a rotary-driven pore-controlled fiber filter, and recirculates a portion of the treated water containing ozone-containing nanobubbles as backwash water for the fiber filter to improve the cleaning efficiency of the fiber filter media. Background Technology

[0003] With the recent increase in water scarcity, the need for water resource recycling, stricter effluent quality standards, and the necessity of carbon-reducing water treatment technologies, advanced treatment technologies are becoming increasingly important for converting effluent from sewage or wastewater treatment plants into reusable water rather than simply discharging it.

[0004] Generally, for the reuse of effluent, suspended solids, turbidity, color, organic matter, microorganisms, and odor-causing substances must be reduced to levels below a certain threshold. To this end, processes such as sand filtration, membrane filtration, activated carbon adsorption, ozone oxidation, UV treatment, chlorine disinfection, and fiber filtration have been applied.

[0005] However, conventional sand filtration or general fiber filtration methods suffered from reduced filtration efficiency due to the accumulation of suspended solids and organic matter on the surface of the filter media after a certain period of operation, as well as the problem of requiring a large amount of washing water during the backwashing process. In particular, since the effluent contained a mixture of fine suspended solids, microflocs, algae-derived substances, non-biodegradable organic matter, and sticky organic matter, it was difficult to sufficiently remove contaminants attached to the inside or surface of the fiber media using only standard hydraulic backwashing.

[0006] Furthermore, while the ozone oxidation process is effective for decomposing recalcitrant organic matter, reducing color, sterilizing, and deodorizing, oxidation efficiency may decrease if the ozone retention time and contact efficiency are insufficient. In particular, if the ozone bubbles are too large or the contact area with the effluent is insufficient, there is a problem where the ozone is released into the atmosphere before it is sufficiently dissolved, resulting in a low ozone utilization rate.

[0007] To address this, oxidation treatment technology utilizing nanobubbles is being proposed. Compared to ordinary bubbles, nanobubbles are significantly smaller, have a longer residence time in water, and possess a large gas-liquid contact surface area, making them advantageous for maintaining gases such as ozone, oxygen, or air in water for extended periods. However, simply supplying nanobubbles to the ozone contact tank alone is insufficient to adequately retain and aggregate the fine oxidation flux formed after oxidation treatment, nor can it resolve issues such as clogging and backwashing in the downstream filtration process.

[0008] Meanwhile, fiber filters are devices that capture fine particles and suspended solids using the pores of fibrous filter media, offering the advantages of relatively high filtration efficiency and large treatment flow rates. However, if contaminants accumulate on the fiber media, filtration resistance increases and filtration performance deteriorates; furthermore, if the backwashing process is insufficient, there is a problem in that the filter media cannot be regenerated stably for a long period.

[0009] In particular, since conventional fiber filter backwashing methods relied primarily on the water pressure or air cleaning of the backwash water, it was difficult to effectively remove organic contaminants, oxidized flocs, and biofilm components that had penetrated or adhered between the fiber media. Furthermore, if simple treated water or external cleaning water is used for backwashing, issues regarding securing separate backwash water and treating effluent may arise.

[0010] Therefore, there is a need for a new system that enables long-term stable operation by increasing the efficiency of ozone and nanobubble oxidation treatment in effluent reuse treatment systems, stably filtering out fine oxidation flux generated after oxidation treatment, and improving the backwashing efficiency of fiber filters. Prior art literature

[0011] Korean Published Patent No. 10-2025-0054633 The problem to be solved

[0012] The present invention is intended to solve the above-mentioned problems, and

[0013] 1) The present invention aims to provide a wastewater reuse treatment system capable of effectively oxidizing wastewater using ozone-containing nanobubbles, sufficiently retaining the micro-oxidation flux generated during the oxidation process in a retention zone, and then filtration it with high efficiency through a rotary-driven pore-controlled fiber filter.

[0014] 2) In addition, the present invention aims to provide a wastewater reuse treatment system capable of simultaneously removing organic matter, microflocs, adhesive contaminants, and biofilms attached to the fiber filter media through chemical oxidation and physical cleaning by recirculating a portion of the treated water from an ozone contact tank as backwash water for a rotary-driven pore-controlled fiber filter, wherein the recirculated treated water contains ozone-containing nanobubbles.

[0015] 3) In addition, the present invention aims to provide a wastewater reuse treatment system capable of applying a combination of water pressure and centrifugal force acting on the fiber filter media by supplying treated water containing ozone-containing nanobubbles into the interior of a porous tube during a backwashing process to clean the fiber filter media from the inside out, and simultaneously rotating the porous tube at a higher speed than during the filtration process.

[0016] 4) In addition, the present invention aims to provide a wastewater reuse treatment system capable of stably maintaining backwash efficiency by installing an ozone sensor and a flow sensor in the recirculation line and adjusting the nanobubble supply amount and the degree of opening of the recirculation control valve according to the residual ozone concentration and the recirculation flow rate.

[0017] 5) In addition, the present invention aims to provide a wastewater reuse treatment system that can stabilize the load of the downstream fiber filter and improve the water quality of the wastewater reused by installing a baffle plate between the oxidation zone and the retention zone to block the straight flow of the treated water and increase the retention time of the fine oxidation flux.

[0018] 6) In addition, the present invention aims to provide a wastewater reuse treatment system capable of improving the contact efficiency and oxidation efficiency of ozone and nanobubbles through collisions between nanobubbles and the formation of vortices by providing a vortex-forming injection module comprising a plurality of injection nozzles arranged at an angle in mutually opposing directions at the bottom of the oxidation zone. means of solving the problem

[0019] To achieve the above objective, a wastewater reuse treatment system using a rotary-driven pore-controlled fiber filter according to the present invention comprises: an ozone contact tank for oxidizing wastewater; a nanobubble supply unit for supplying nanobubbles to the ozone contact tank; a rotary-driven pore-controlled fiber filter disposed downstream of the ozone contact tank; and a recirculation line for supplying a portion of the treated water processed in the ozone contact tank as backwash water to the rotary-driven pore-controlled fiber filter.

[0020] In a preferred embodiment, the ozone contact tank comprises an oxidation zone to which ozone-containing nanobubbles are supplied, a retention zone formed downstream of the oxidation zone to retain fine oxidation flux, and a lateral discharge section for discharging the supernatant of the retention zone, and the nanobubble supply section may include a first supply line for supplying nanobubbles to the oxidation zone and a second supply line for supplying nanobubbles to the recirculation line.

[0021] In addition, the recirculation line may include an intake end connected to the retention area or lateral discharge part of the ozone contact tank, a supply end connected to the inside of the porous tube of the rotary drive type pore control fiber filter, and a recirculation control valve that opens during the backwashing process.

[0022] In addition, as a preferred embodiment of the present invention, during a backwashing process, the present invention supplies treated water containing ozone-containing nanobubbles through the recirculation line into the porous tube to wash the fiber filter material placed on the outside of the porous tube from the inside out, and the recirculation line is equipped with an ozone sensor that detects residual ozone concentration, so that when residual ozone below a set concentration is detected by the ozone sensor, the supply amount of the nanobubble supply unit is increased.

[0023] In addition, a flow sensor may be installed in the recirculation line, so that a recirculation control valve is additionally opened when the recirculation flow rate decreases below a set value during the backwashing process.

[0024] As an embodiment of the present invention, the rotary drive type porous control fiber filter may be configured to clean by rotating the rotational speed of the porous tube at a higher speed than during the filtration process during the backwashing process, and applying a combination of the water pressure of the backwash water sprayed from the inside to the outside and the centrifugal force applied to the fiber filter material.

[0025] In addition, in one embodiment of the present invention, a baffle plate may be installed between the oxidation zone and the retention zone to block the straight flow of the treated water and increase the retention time of the fine oxidation flux.

[0026] In addition, the first supply line of the nanobubble supply unit may be positioned below the oxidation region and may include a vortex-forming injection module in which a plurality of injection nozzles are arranged at an angle facing each other to form a vortex caused by collision between the injected nanobubbles.

[0027] In addition, as a preferred embodiment of the present invention, a wastewater reuse treatment system may include: an ozone contact tank for oxidizing wastewater; a nanobubble supply unit for supplying ozone-containing nanobubble water to the ozone contact tank; a rotary-driven pore-controlled fiber filter disposed downstream of the ozone contact tank for filtering the oxidized treated water discharged from the ozone contact tank; and a recirculation line connecting the ozone contact tank and the rotary-driven pore-controlled fiber filter, wherein, during the backwashing process of the rotary-driven pore-controlled fiber filter, the oxidized treated water discharged from the ozone contact tank and the ozone-containing nanobubble water supplied from the nanobubble supply unit are supplied as backwash water to the rotary-driven pore-controlled fiber filter.

[0028] The ozone contact tank may include an oxidation zone in which incoming effluent and ozone-containing nanobubble water are mixed to perform an oxidation reaction on the effluent and a fine oxidation flux is formed by the oxidation reaction, a retention zone formed downstream of the oxidation zone to retain the fine oxidation flux for a predetermined time to coagulate and stabilize it, and a side discharge section for discharging the supernatant of the retention zone.

[0029] The above nanobubble supply unit may include a nanobubble generator that generates ozone-containing nanobubble water, a first supply line that connects the ozone contact tank and the nanobubble supply unit and supplies the ozone-containing nanobubble water generated from the nanobubble generator to the oxidation zone, and a second supply line that connects the nanobubble supply unit and the recirculation line and supplies the ozone-containing nanobubble water generated from the nanobubble generator to the recirculation line.

[0030] The above rotary drive type air gap control fiber filter includes a porous tube installed inside a filtration tank and having a plurality of spray holes formed through it, a plurality of fiber filter media installed on the outside of the porous tube, and a driving unit that controls the operation of winding or unwinding the fiber filter media around the porous tube.

[0031] The above recirculation line includes an intake end connected to a lateral discharge part of the ozone contact tank, a supply end connected to the inside of the porous tube of the rotary drive type porous control fiber filter, and a recirculation control valve that opens during the backwashing process. During the backwashing process, the oxidized treated water and ozone-containing nanobubble water are combined in the recirculation line, and backwash water composed of the oxidized treated water and ozone-containing nanobubble water is supplied into the porous tube through the recirculation line and sprayed outwardly through a spray hole to clean the fiber filter media placed on the outside of the porous tube from the inside outward. An ozone sensor for detecting ozone concentration is installed in the recirculation line, and when the residual ozone concentration in the recirculation line is detected by the ozone sensor to be below a set concentration, the control unit controls the supply amount of ozone-containing nanobubble water supplied from the nanobubble supply unit to increase. A flow sensor is installed in the recirculation line, and when the flow rate of the backwash water detected by the flow sensor decreases below a set value during the backwashing process The control unit can control the recirculation control valve to open further.

[0032] In addition, during the backwashing process, the rotary drive type pore control fiber filter can be driven by the drive unit so that the operation of winding and unwinding the fiber filter material around the porous tube is repeated.

[0033] In addition, as an embodiment of the present invention, a plurality of baffle plates are installed between the oxidation zone and the retention zone to block the straight flow of the oxidized water and increase the retention time of the fine oxidation flux, and an uneven surface may be formed on the surface of the baffle plates to disturb the flow of the treated water.

[0034] In addition, as one embodiment, a vortex-forming injection module is installed at the outlet end of the first supply line of the nanobubble supply unit, and the vortex-forming injection module is equipped with a plurality of injection nozzles, and the plurality of injection nozzles can be configured to inject ozone-containing nanobubble water at a predetermined angle so as to form a vortex flow inside the oxidation zone of the ozone contact tank. Effects of the invention

[0035] According to the present invention, since the effluent is oxidized by ozone-containing nanobubbles, non-degradable organic matter, color-causing substances, fine suspended solids, odor-causing substances, and microorganisms in the effluent can be effectively reduced.

[0036] In addition, according to the present invention, the ozone contact tank includes an oxidation zone and a retention zone, and since the fine oxidation flux is retained in the retention zone for a certain period of time, the fine flux generated after the oxidation reaction is stabilized and can be effectively removed by a downstream fiber filter.

[0037] In addition, according to the present invention, by discharging the supernatant of the retention area through a lateral discharge section, the excessive inflow of settling substances or fine flux to the downstream end can be suppressed, and the filtration load of the downstream fiber filter can be stably maintained.

[0038] In addition, according to the present invention, since a portion of the treated water from the ozone contact tank is recirculated as backwash water for the fiber filter, the amount of separate backwash water used can be reduced and the water reuse efficiency can be improved.

[0039] In addition, according to the present invention, since the recirculated treated water contains residual ozone-containing nanobubbles, organic contaminants, adhesive contaminants, biofilms, and micro-oxidation flux attached to the fiber filter media can be cleaned while oxidizing and decomposing them during the backwashing process.

[0040] In addition, according to the present invention, backwash water is sprayed from inside the porous tube outward to clean the fiber filter media from the inside outward, so contaminants accumulated on the outside or inside of the fiber filter media during the filtration process can be effectively removed.

[0041] In addition, according to the present invention, by rotating the porous tube at a higher speed during the backwashing process than during the filtration process, the centrifugal force caused by the rotation, as well as the water pressure of the backwash water, acts together on the fiber filter media, thereby promoting the spreading, shaking, expansion, and detachment of contaminants from the fiber filter media.

[0042] In addition, according to the present invention, the residual ozone concentration is detected by an ozone sensor in the recirculation line, and the nanobubble supply amount can be increased when the residual ozone concentration is below a set concentration, so that the oxidative cleaning power can be maintained above a certain level during the backwashing process.

[0043] In addition, according to the present invention, the recirculation flow rate is detected by a flow sensor of the recirculation line, and the recirculation control valve can be additionally opened when the flow rate decreases below a set value, thereby ensuring a stable backwash flow rate even in the event of a clogged fiber filter or changes in backwash load.

[0044] In addition, according to the present invention, by installing a baffle plate between the oxidation zone and the retention zone to block the straight flow of the treated water, short-circuiting can be prevented and the retention time of the fine oxidation flux can be increased.

[0045] In addition, according to the present invention, by providing a plurality of spray nozzles arranged at an angle facing each other in the lower part of the oxidation zone, collisions and vortices are formed between nanobubbles, thereby improving the contact efficiency between ozone, nanobubbles, and discharge water. Brief explanation of the drawing

[0046] FIG. 1 is a schematic diagram showing the overall configuration of a wastewater reuse treatment system according to one embodiment of the present invention. FIG. 2 is a schematic diagram of an ozone contact tank to explain the arrangement relationship of the oxidation zone, retention zone, and lateral discharge section of an ozone contact tank according to one embodiment of the present invention. FIG. 3 is a diagram illustrating the operation of a baffle plate installed between an oxidation zone and a retention zone according to one embodiment of the present invention. FIG. 4 is a diagram showing the configuration of a vortex-forming injection module according to one embodiment of the present invention. FIG. 5 is a diagram showing the state in which collisions and vortices are formed between nanobubble water by a plurality of spray nozzles according to one embodiment of the present invention. FIG. 6 is a drawing illustrating the configuration of a rotary drive type air gap control type fiber filter according to one embodiment of the present invention. FIG. 7 is a diagram illustrating the arrangement relationship of a recirculation line, a second supply line, an ozone sensor, and a flow sensor according to an embodiment of the present invention. FIG. 8 is a block diagram showing the control flow of a backwash process according to one embodiment of the present invention. FIG. 9 is a diagram showing the internal configuration of a rotary drive type air gap control type fiber filter according to one embodiment of the present invention. FIG. 10 is a drawing illustrating the state in which a fibrous filter material is wound around a porous tube during a filtration process according to one embodiment of the present invention. FIG. 11 is a drawing for explaining the process of backwash water overflowing during a backwash process and the process of backwash air being sprayed from the bottom of the filter tank or the bottom plate of the filter media holder according to one embodiment of the present invention. FIG. 12 is a cross-sectional view illustrating the structure of a filter holder top plate according to one embodiment of the present invention. FIG. 13 is a cross-sectional view illustrating the structure of the lower plate of a filter holder according to one embodiment of the present invention. FIG. 14 is a drawing illustrating the state in which a fiber filter material is connected to the top plate of a filter holder through a filter material ring according to one embodiment of the present invention. FIG. 15 is a drawing illustrating a state in which a fiber filter material is connected to the lower plate of a filter holder through a filter material ring according to one embodiment of the present invention, and a state in which backwash air is sprayed toward the fiber filter material from a backwash air injection hole. FIG. 16 is a diagram illustrating the driving control relationship of a rotary cylinder through a driving unit of a rotary drive type air gap control type fiber filter according to one embodiment of the present invention. Specific details for implementing the invention

[0047] Preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings. However, the present invention is not limited to the following embodiments, and various modifications are possible within the scope of the technical concept of the present invention.

[0048] The present invention relates to a wastewater reuse treatment system, wherein the wastewater is oxidized using ozone-containing nanobubbles, and the fine oxidation flux formed during the oxidation treatment process is retained and then filtered using a rotary drive type pore control fiber filter (130).

[0049] In particular, the present invention is configured such that a portion of the oxidized water, which is treated water that has undergone oxidation treatment in an ozone contact tank (110) or treated water in which an oxidation reaction has taken place, is supplied as backwash water to a rotary drive type pore control type fiber filter (130) through a recirculation line (140), and additionally supplies ozone-containing nanobubble water to the recirculation line (140), thereby supplying the treated water containing ozone-containing nanobubbles into the interior of a porous tube (132) and spraying it from the inside to the outside through a spray hole.

[0050] Accordingly, the present invention provides a wastewater reuse treatment system in which not only simple physical backwashing but also oxidative cleaning by ozone-containing nanobubbles, hydraulic cleaning of backwash water sprayed from the inside to the outside, and cleaning of pore changes due to repeated winding and unwinding of the fiber filter material (133) are combined.

[0051] 1. Configuration of the entire system

[0052] As shown in FIG. 1, the wastewater reuse treatment system of the present invention may include an ozone contact tank (110), a nanobubble supply unit (120), a rotary drive type pore control fiber filter (130), a recirculation line (140), and a control unit (150).

[0053] The ozone contact tank (110) is configured to oxidize and treat the discharge water. Here, the discharge water may include sewage or raw water discharged from a sewage treatment plant, a wastewater treatment plant, an industrial wastewater treatment facility, a public sewage treatment facility, or other water treatment facilities.

[0054] The nanobubble supply unit (120) is configured to supply ozone-containing nanobubble water or ozone-containing nanobubbles to the oxidation zone (111) and recirculation line (140) of the ozone contact tank (110). In the present invention, the ozone-containing nanobubbles may include ozone, oxygen, air, or a mixture of these gases, and preferably may be nanobubbles containing ozone.

[0055] In other words, in the present invention, “ozone-containing nanobubbles” refers to a state in which a gas containing ozone (O₃) is dispersed within a liquid in the form of nano-sized bubbles.

[0056] The ozone-containing nanobubbles described above are ultrafine bubbles containing ozone gas, and can be formed with a bubble diameter of nanometers (nm) or micrometers (μm) or less.

[0057] The ozone-containing nanobubbles described above may contain ozone gas inside the bubbles and, if necessary, may include a form in which an ozone component exists at the interface of the bubbles or in the liquid phase region surrounding the bubbles.

[0058] The ozone-containing nanobubbles mentioned above have a much smaller bubble size compared to general aeration bubbles, which can increase the residence time in water and the contact area with the discharge water, and accordingly, the oxidation reaction efficiency can be improved.

[0059] In addition, the ozone-containing nanobubbles can induce an oxidation reaction while in contact with organic matter, color-causing substances, odor components, colloidal substances, and fine suspended solids in the effluent, and can promote the formation of fine oxidation flux.

[0060] In addition, the ozone-containing nanobubbles can penetrate into the pores of the fiber filter material during the backwashing process and facilitate the detachment of contaminants attached to the fiber filter material.

[0061] A rotary drive type air gap control fiber filter (130) is positioned at the rear end of the ozone contact tank (110) and is configured to filter fine oxidation flux, suspended solids, turbidity-causing substances, and residual particles in the oxidized treated water.

[0062] The recirculation line (140) is configured to supply a portion of the oxidized water, i.e., the oxidized water, from the ozone contact tank (110) as backwash water to the rotary drive type pore control type fiber filter (130).

[0063] The control unit (150) can control the operation of the nanobubble supply unit (120), recirculation control valve (143), ozone sensor (145), flow sensor (146), drive unit (134), and pump, etc.

[0064] 2. Composition of the Ozone Contact Tank

[0065] As shown in FIG. 2, the ozone contact tank (110) includes an oxidation zone (111), a retention zone (112), and a lateral discharge section (113).

[0066] The oxidation zone (111) is a zone where ozone-containing nanobubbles are supplied. When discharge water flows into the oxidation zone (111), ozone-containing nanobubble water is supplied through the first supply line (122) of the nanobubble supply unit (120), and

[0067] In the oxidation zone (111), ozone-containing nanobubbles can oxidize organic matter, color components, odor components, microorganisms, colloidal substances, and fine suspended matter as they come into contact with the discharge water.

[0068] During this process, fine pollutants in the effluent may undergo changes in surface properties or aggregate with each other to form micro-oxidation flocs.

[0069] That is, in the oxidation region (111), the discharge water and ozone-containing nanobubble water can be mixed, and an oxidation reaction can be performed on the discharge water by the ozone contained in the ozone-containing nanobubble water.

[0070] Organic pollutants, colloidal substances, fine suspended solids, color-causing substances, and odor-causing substances contained in the effluent may be decomposed or oxidized by the above oxidation reaction.

[0071] In addition, during the above oxidation reaction process, the oxidation product and fine particles can combine to form a fine oxidation flux.

[0072] The retention area (112) is formed downstream of the oxidation area (111) as shown in FIG. 2. The retention area (112) is an area where the treated water (oxidized water) oxidized in the oxidation area (111) is retained for a certain period of time to stabilize the fine oxidation flux.

[0073] In the retention area (112), the residual ozone-containing nanobubbles after the oxidation reaction can continue to function, and the fine oxidation flux generated by the oxidation treatment can be maintained in a state suitable for being captured by the fiber filter (130) at the rear.

[0074] In this specification, "downstream side" may refer to a direction located at the rear end based on the flow direction of the treated water. For example, the fact that the retention area (112) is formed downstream of the oxidation area (111) may mean a positional relationship in which the treated water flows into the retention area (112) after passing through the oxidation area (111).

[0075] The above retention area (112) can be formed such that the flow rate is relatively reduced compared to the oxidation area (111). Additionally, a baffle plate (114) placed between the oxidation area (111) and the retention area (112) can suppress the straight flow of the treated water and extend the flow path, thereby increasing the retention time of the treated water.

[0076] Accordingly, the fine oxidation flux generated in the oxidation zone (111) can remain in the retention zone (112) for a certain period of time and aggregate and grow.

[0077] In addition, as the flow rate is reduced within the retention area (112), the redispersion of fine oxidation flux can be suppressed and stabilization achieved. Accordingly, the filtration efficiency of the rear rotary drive type pore control fiber filter (130) can be improved.

[0078] The lateral discharge section (113) is configured to discharge the supernatant of the retention area (112). The lateral discharge section (113) may be formed on the side or upper side of the retention area (112).

[0079] The supernatant discharged through the side discharge section (113) is relatively stabilized oxidized treated water and can be supplied to the rear rotary drive type pore control fiber filter (130). Additionally, the side discharge section (113) can be connected to the intake section (141) of the recirculation line (140), so that a portion of the oxidized treated water can be recycled as backwash water.

[0080] In this specification, “superior water” may refer to treated water located relatively higher among the treated water that remains in the retention area (112) for a certain period of time after oxidation treatment.

[0081] In other words, the supernatant is a relatively stabilized treated water in which fine oxidation flux is formed, and may have a relatively low concentration of suspended solids compared to the flux concentration area that settles or remains in the lower part of the retention area (112).

[0082] In the present specification, "oxidation treated water" may refer to treated water generated after an oxidation reaction is performed by mixing discharge water and ozone-containing nanobubble water in an oxidation zone (111).

[0083] The above oxidation-treated water may contain fine oxidation flux formed by an oxidation reaction, and may, if necessary, contain residual ozone, ozone-containing nanobubbles, or a portion of ozone-containing nanobubble water.

[0084] In addition, the above-mentioned oxidized water can be supplied to a rotary-driven pore-controlled fiber filter (130) and filtered after undergoing the process of aggregation and stabilization of fine oxidized flux in the retention area (112), and can be reused as backwash water for the rotary-driven pore-controlled fiber filter (130) through the recirculation line (140) during the backwash process.

[0085] 3. Composition of the baffle plate

[0086] As shown in FIGS. 2 and 3, a baffle plate (114) may be installed between the oxidation area (111) and the retention area (112).

[0087] The baffle plate (114) can be configured to reduce the flow velocity by blocking the straight flow of treated water moving from the oxidation zone (111) to the retention zone (112). Accordingly, short-circuiting of the treated water passing through the inside of the ozone contact tank (110) in a short time is prevented, and the retention time of the treated water can be increased.

[0088] When the flow path of the treated water is extended by the baffle plate (114), the contact time between the ozone-containing nanobubbles and the discharge water increases, and the oxidation reaction and the stabilization of the micro-oxidation flux are promoted.

[0089] Additionally, the baffle plate (114) can reduce the flow rate within the retention area (112) to prevent the rapid outflow of fine oxidation flux to the rear end. Accordingly, the load of the treated water flowing into the rear rotary drive type pore control fiber filter (130) can be stabilized.

[0090] At least one baffle plate (114) may be installed between the oxidation area (111) and the retention area (112).

[0091] The above baffle plate (114) is configured to block the short circuit flow of the treated water and extend the flow path of the treated water to increase the residence time. The baffle plate (114) may be installed in multiple numbers, and the multiple baffle plates (114) may be spaced apart at regular intervals along the flow direction of the treated water.

[0092] For example, multiple baffle plates (114) can be arranged alternately in the up and down directions to induce the treated water to move in a zigzag pattern.

[0093] Specifically, some baffle plates (114) may be formed extending downward from the upper part of the ozone contact tank (110), and other baffle plates (114) may be formed extending upward from the lower part of the ozone contact tank (110).

[0094] Accordingly, the treated water repeatedly moves up and down while bypassing the baffle plate (114), and the flow path of the treated water can be increased.

[0095] In addition, the baffle plate (114) can suppress the rapid extinction of rotational flow or vortex formed in the oxidation zone (111) and allow a gentle flow state to be maintained within the retention zone (112).

[0096] Accordingly, the contact time between ozone-containing nanobubbles and treated water increases, and the oxidation reaction efficiency and the formation efficiency of fine oxidation fluxes can be improved.

[0097] In addition, the baffle plate (114) can reduce the flow rate of the treated water within the retention area (112) so that the fine oxidation flux remains or stabilizes for a certain period of time.

[0098] That is, within the retention area (112), as the flow rate of the treated water decreases, the movement speed of the fine oxidation flux is reduced, and collision and aggregation between the fine oxidation fluxes can be promoted.

[0099] Accordingly, the fine oxide flux can grow and stabilize in the retention area (112) and can be more easily collected by the rear rotary drive type pore control fiber filter (130).

[0100] In particular, the baffle plate (114) can induce the formation of a flux concentration area on the lower side of the retention area (112) and relatively stable supernatant water on the upper side.

[0101] Therefore, the lateral discharge section (113) can stably collect supernatant water with a relatively low flux concentration.

[0102] Additionally, the shape of the baffle plate (114) may be formed in one or more of the following: a flat plate, a curved plate, an inclined plate, or a folded plate. If necessary, a flow dispersion hole or a water passage hole may be formed in a part of the baffle plate (114), thereby mitigating localized turbulent concentration of the treated water and inducing flow dispersion.

[0103] An uneven surface (114a) may be formed on the surface of the above baffle plate (114).

[0104] The above-mentioned uneven portion (114a) may be formed on one or both sides of the baffle plate (114) and may be formed as one or more of a protruding rib, groove, wavy portion, embossed portion, or sawtooth-shaped projection extending in a direction intersecting the flow direction of the treated water.

[0105] The above-mentioned uneven portion (114a) can further disrupt the straight flow of the treated water moving from the oxidation area (111) to the retention area (112) to form fine turbulence, and increase the contact area and contact time between the ozone-containing nanobubbles and the treated water.

[0106] In addition, the above-mentioned uneven portion (114a) can suppress the rapid movement of fine oxide flux along the baffle plate (114) and promote the retention and stabilization of fine oxide flux within the retention area (112).

[0107] 4. Composition of the nanobubble supply unit

[0108] The nanobubble supply unit (120) includes a nanobubble generator (121), a first supply line (122), and a second supply line (123).

[0109] The nanobubble generator (121) is configured to generate ozone, oxygen, air, or a mixture of these gases in the form of nanobubbles, and is configured to generate a gas containing ozone in the form of nano-sized bubbles and disperse them inside a liquid to supply ozone-containing nanobubble water.

[0110] The above nanobubble generator (121) can generate ozone-containing nanobubbles by mixing ozone gas supplied from an ozone source with a liquid.

[0111] The above nanobubble generator (121) can generate ozone-containing nanobubbles in one or more of the following methods: a venturi method, a pressurized dissolution method, a cavitation method, an ultrasonic method, or a rotary shear method.

[0112] For example, a nanobubble generator (121) can form a negative pressure region or a shear region by flowing the treated water or a separate circulating water at high speed, and can form microbubbles by injecting ozone gas into the region.

[0113] Additionally, the nanobubble generator (121) may include an internal stirring channel, a gas-liquid mixing section, a pressurized chamber, a venturi nozzle, a rotating impeller, or a fine dispersion section.

[0114] The ozone-containing nanobubbles generated in the above nanobubble generator (121) can be formed into nano-sized or micro-sized bubbles with a diameter that is very small compared to general aeration bubbles.

[0115] Accordingly, ozone-containing nanobubbles can remain in the liquid for a long time, the contact area with the discharge water can be increased, and the ozone transfer efficiency and oxidation reaction efficiency can be improved.

[0116] In addition, ozone-containing nanobubbles can increase the contact efficiency with colloidal substances, fine suspended solids, and organic pollutants in effluent due to their surface charge and microbubble characteristics.

[0117] In this specification, "ozone-containing nanobubbles" may mean nanometer (nm) sized microbubbles containing ozone (O₃).

[0118] In addition, "ozone-containing nanobubble water" may refer to a fluid in which the ozone-containing nanobubbles are dispersed in water.

[0119] That is, ozone-containing nanobubbles refer to the bubbles themselves, and ozone-containing nanobubble water may refer to a liquid fluid in which the ozone-containing nanobubbles are contained or dispersed in water.

[0120] Accordingly, in the present invention, the nanobubble generator (121) can generate ozone-containing nanobubbles and mix them with water to generate ozone-containing nanobubble water, and the ozone-containing nanobubble water can be supplied through the first supply line (122) and the second supply line (123).

[0121] In particular, in the present invention, ozone-containing nanobubbles generated in a nanobubble generator (121) can be supplied to an oxidation zone (111) through a first supply line (122) and used for oxidation treatment of discharge water, and can be supplied to a recirculation line (140) through a second supply line (123) and used as oxidative cleaning water during a backwashing process.

[0122] Therefore, since ozone-containing nanobubbles can be supplied to both the oxidation process and the backwashing process using a single nanobubble generator (121), the system configuration can be simplified and the equipment efficiency can be improved.

[0123] The first supply line (122) supplies nanobubbles generated from the nanobubble generator (121) to the oxidation zone (111).

[0124] The first supply line (122) is a flow path for supplying ozone-containing nanobubbles generated in a nanobubble generator (121) to an oxidation zone (111) of an ozone contact tank (110). The first supply line (122) can be connected to the lower side of the oxidation zone (111) and can be configured so that the ozone-containing nanobubbles rise from the lower side of the oxidation zone (111) toward the upper side and come into contact with the discharge water.

[0125] Accordingly, the ozone-containing nanobubbles can be in contact with the discharge water for a long time while moving upward inside the oxidation zone (111), and the ozone transfer efficiency and oxidation reaction efficiency can be improved.

[0126] Additionally, the first supply line (122) may be formed into multiple branches along the longitudinal direction of the oxidation zone (111), and the multiple branch lines may be spaced apart at the bottom of the oxidation zone (111). Accordingly, ozone-containing nanobubbles can be more uniformly dispersed throughout the entire interior of the oxidation zone (111), and the phenomenon of bubbles being concentrated only in specific areas can be reduced.

[0127] A vortex-forming injection module (126) may be installed at the end of the first supply line (122). The vortex-forming injection module (126) may include a plurality of injection nozzles (127), and the plurality of injection nozzles (127) may be arranged at an angle facing each other.

[0128] Accordingly, the ozone-containing nanobubble water sprayed can form rotational flow and micro-vortices while colliding with each other or forming cross-flow within the oxidation zone (111).

[0129] These vortices can promote the mixing of ozone-containing nanobubble water and discharge water, increase the residence time of ozone-containing nanobubbles, and promote the formation of fine oxidation flux inside the oxidation zone (111).

[0130] In addition, the first supply line (122) may be further equipped with a supply pump to maintain supply pressure, a flow control valve to regulate the supply amount, and a check valve to prevent backflow.

[0131] The control unit (150) can adjust the supply amount of ozone-containing nanobubbles through the first supply line (122) according to the flow rate of the discharge water, the pollution load, the residual ozone concentration, or the operating condition of the oxidation zone (111).

[0132] The second supply line (123) supplies ozone-containing nanobubble water generated from the nanobubble generator (121) to the recirculation line (140). By additionally supplying ozone-containing nanobubbles (water) to the recirculation line (140) through the second supply line (123), the backwash water supplied into the porous tube (132) during the backwash process can function as oxidative cleaning water containing ozone and nanobubbles.

[0133] A supply pump, a flow control valve, or a check valve may be installed in the second supply line (123) as needed. The control unit (150) can increase or decrease the amount of nanobubbles supplied through the second supply line (123) according to the detection value of the ozone sensor (145).

[0134] More specifically, the second supply line (123) is a flow path for supplying ozone-containing nanobubble water generated in the nanobubble generator (121) to the recirculation line (140), and the second supply line (123) can be formed to connect the discharge side of the nanobubble generator (121) and the intermediate section of the recirculation line (140).

[0135] Accordingly, ozone-containing nanobubbles can be additionally supplied to the oxidative treatment water moving through the recirculation line (140) during the backwashing process, and the treatment water flowing through the recirculation line (140) can function as oxidative cleaning water containing ozone-containing nanobubbles.

[0136] The ozone-containing nanobubbles or ozone-containing nanobubble water supplied through the second supply line (123) can travel along the recirculation line (140) and be supplied into the interior of the porous tube (132). Subsequently, the treated water containing ozone-containing nanobubbles (i.e., backwash water mixed with oxidation treated water and ozone-containing nanobubble water) can be sprayed outward from the porous tube (132) through the spray holes of the porous tube (132).

[0137] Accordingly, ozone-containing nanobubbles present in the backwash water can penetrate into the pores of the fiber filter material (133) and promote the detachment of micro-oxidation flux, organic pollutants, adhesive pollutants, and biofilm components attached to the fiber filter material (133).

[0138] Additionally, ozone-containing nanobubbles can be introduced into the pores that change due to the repeated winding and unwinding of the fiber filter material (133) during the backwashing process, and accordingly, cleaning action can be performed even into the fine pores of the fiber filter material (133).

[0139] A supply pump (124) for maintaining the movement pressure of ozone-containing nanobubbles may be installed in the second supply line (123). The supply pump (124) can provide pressure to stably supply ozone-containing nanobubbles generated in the nanobubble generator (121) into the recirculation line (140).

[0140] In addition, a flow control valve (125) for controlling the supply amount of ozone-containing nanobubbles may be installed in the second supply line (123).

[0141] The flow control valve (125) can have its opening rate controlled by the control unit (150), and accordingly, the amount of ozone-containing nanobubbles supplied to the recirculation line (140) through the second supply line (123) can be controlled.

[0142] For example, when the residual ozone concentration inside the recirculation line (140) is detected to be below a set concentration by the ozone sensor (145), the control unit (150) can increase the driving output of the supply pump (124) or increase the opening rate of the flow control valve (125) to increase the supply amount of ozone-containing nanobubbles through the second supply line (123).

[0143] In this specification, "residual ozone" may refer to ozone that remains in the oxidized water even after the ozone contained in the ozone-containing nanobubble water has been used in an oxidation reaction with the effluent.

[0144] The above residual ozone may include ozone dissolved in the oxidized water and ozone contained within ozone-containing nanobubbles, and may contribute to maintaining the oxidizing power of the oxidized water and improving cleaning efficiency during the backwashing process.

[0145] In addition, the concentration of the residual ozone can be detected by an ozone sensor (145), and the control unit (150) can control the amount of ozone-containing nanobubble water supplied by the nanobubble supply unit (120) based on the detected residual ozone concentration.

[0146] Additionally, a check valve may be additionally installed in the second supply line (123) to prevent the treated water of the recirculation line (140) from flowing back. Therefore, the second supply line (123) is not merely a simple bubble supply line, but can supply ozone-containing nanobubbles to the recirculation line (140) during the backwashing process to enhance the oxidative cleaning function and improve the cleaning efficiency and backwashing efficiency of the fiber filter material (133).

[0147] In one embodiment, a supply pump (124) for transferring ozone-containing nanobubbles to the recirculation line (140) may be installed in the second supply line (123). The supply pump (124) may provide pressure to allow ozone-containing nanobubbles generated from the nanobubble generator (121) to move stably along the recirculation line (140).

[0148] In particular, even when the internal pressure of the recirculation line (140) increases during the backwashing process or when backwash water is sprayed through the spray holes of the porous tube (132), the supply pump (124) can stably supply ozone-containing nanobubbles into the recirculation line (140).

[0149] In addition, the supply pump (124) can have its driving speed or discharge amount adjusted by the control of the control unit (150).

[0150] For example, when the residual ozone concentration is detected to be below a set concentration by the ozone sensor (145), the control unit (150) can increase the rotational speed of the supply pump (124) to increase the supply amount of ozone-containing nanobubbles supplied through the second supply line (123).

[0151] Additionally, the supply pump (124) may be formed as one or more of a metering pump, a diaphragm pump, a centrifugal pump, or a gas-liquid mixing transfer pump. If necessary, a flow control valve (125) may be additionally installed in the second supply line (123), and the flow control valve (125) can finely control the supply flow rate of ozone-containing nanobubbles by controlling the opening rate of the valve by the control unit (150).

[0152] 5. Configuration of the vortex-forming injection module

[0153] The first supply line (122) can be positioned below the oxidation zone (111) as shown in FIG. 4 and may be equipped with a vortex-forming injection module (126) including a plurality of injection nozzles (127).

[0154] A plurality of injection nozzles (127) of the vortex-forming injection module (126) can be arranged at an angle facing each other.

[0155] For example, spray nozzles (127) positioned on both sides at the bottom of the oxidation zone (111) may be configured to spray nanobubbles or ozone-containing nanobubble water at an angle facing each other. In this case, the flow of the sprayed nanobubble water collides or crosses each other, forming a rotational flow or vortex inside the oxidation zone (111).

[0156] These vortices can promote the mixing of discharge water with ozone, nanobubbles, or ozone-containing nanobubble water, increase the residence time of nanobubbles in water, and improve the contact efficiency and oxidation reaction efficiency of ozone.

[0157] In addition, vortices formed by opposing inclined spraying or a method of spraying nanobubbles so that they intersect each other can promote the oxidation treatment of colloidal substances, fine suspended solids, and organic pollutants in the effluent and their conversion into fine oxidized flux.

[0158] Accordingly, the vortex-forming injection module (126) is not merely configured to supply nanobubbles or ozone-containing nanobubble water, but also plays a role in improving the contact efficiency of ozone and nanobubbles and the fine oxidation flux formation efficiency within the oxidation zone (111).

[0159] To be explained more specifically below, as an embodiment, the vortex-forming injection module (126) may be configured to be connected to the end of the first supply line (122) to inject ozone-containing nanobubbles or ozone-containing nanobubble water into the oxidation zone (111). That is, the vortex-forming injection module (126) is configured to be placed between the ozone contact tank (110) or the oxidation zone (111) and the first supply line (122) to form a vortex in the flow of ozone-containing nanobubble water supplied from the first supply line (122), thereby causing the ozone-containing nanobubble water to flow in a vortex within the oxidation zone (111).

[0160] The above vortex-forming injection module (126) may include an injection header, a branch pipe, and a plurality of injection nozzles (127).

[0161] The above spray header can perform the function of spraying ozone-containing nanobubble water supplied through the first supply line (122) from a plurality of spray nozzles (127).

[0162] The above branch pipe may be formed to extend in multiple directions from the first supply line (122), and multiple injection nozzles (127) may be installed in each branch pipe.

[0163] The plurality of injection nozzles (127) are formed to be inclined toward each other. More specifically, as shown in FIGS. 4 and 5, ozone-containing nanobubble water can be sprayed from opposing injection nozzles (127) toward the ozone contact tank or oxidation zone at an angle, and arranged so as to intersect each other.

[0164] For example, in two opposing or corresponding spray nozzles, one spray nozzle (127) sprays ozone-containing nanobubble water in the right direction and the other spray nozzle (127) sprays ozone-containing nanobubble water in the left direction, and the two sprayed ozone-containing nanobubble waters may be formed to intersect.

[0165] Accordingly, the ozone-containing nanobubble water sprayed from each spray nozzle (127) flows into the ozone contact tank (110) or oxidation zone (111) while crossing or colliding with each other, and can form rotational flow and vortices within the oxidation zone (111).

[0166] The above-mentioned spray nozzle (127) may be positioned at an angle with respect to the flow direction of the nanobubble water on the ozone contact tank side, and preferably may have an angle of inclination in the range of 10° to 80° relative to the horizontal direction. In one embodiment, it may be formed at an angle of inclination of 45°.

[0167] In addition, multiple injection nozzles (127) may be arranged on the same plane or on the same line, but may be arranged to correspond to or opposite each other, and may be arranged in multiple rows in a multi-stage structure as needed.

[0168] For example, the first row of injection nozzles (127) may be arranged to form a clockwise vortex, and the second row of injection nozzles (127) may be arranged to form a counterclockwise vortex.

[0169] Accordingly, complex stirring flow and turbulent flow can be formed inside the oxidation zone (111), and the mixing efficiency of ozone-containing nanobubble water and discharge water can be improved.

[0170] In addition, the injection head at the tip of the injection nozzle (127) can be formed in a circular, elliptical, slotted, or porous structure.

[0171] For example, a slot-type spray head can diffuse and spray ozone-containing nanobubble water in a fan shape to disperse bubbles over a wider area.

[0172] In addition, the porous spray head can finely disperse ozone-containing nanobubble water through multiple fine spray holes.

[0173] An increasing flow rate section or a decreasing flow rate section may be formed inside the above-mentioned spray nozzle (127), and accordingly, the spraying speed of the ozone-containing nanobubble water may be increased.

[0174] In addition, a rotational induction groove or a spiral channel may be formed inside the injection nozzle (127).

[0175] The above rotational induction groove or spiral channel can induce ozone-containing nanobubble water to be sprayed while rotating, and accordingly, stronger rotational flow and micro-vortices can be formed inside the oxidation zone (111).

[0176] Additionally, multiple vortex-forming injection modules (126) may be spaced apart along the width direction of the oxidation area (111) as needed.

[0177] Accordingly, the ozone-containing nanobubble water can be uniformly dispersed throughout the oxidation region (111), and the phenomenon of bubbles being concentrated only in specific areas can be prevented.

[0178] In addition, the rotational flow and micro-vortex formed by the vortex-forming injection module (126) can increase the residence time of ozone-containing nanobubbles in water and improve ozone transfer efficiency and oxidation reaction efficiency.

[0179] In particular, the above rotational flow can induce colloidal substances, organic pollutants, and fine suspended solids in the effluent to repeatedly come into contact with ozone-containing nanobubbles, thereby promoting the formation of fine oxidation flux.

[0180] In addition, the vortex-forming injection module (126) can suppress the formation of a dead zone where the treated water inside the oxidation zone (111) is locally stagnant, and allow a more uniform oxidation reaction to occur throughout the oxidation zone (111).

[0181] In a preferred embodiment, the vortex-forming injection module (126) may be formed inside the first supply line (122) or in a part of the first supply line (122) (i.e., the end portion).

[0182] The above vortex-forming injection module (126) may include a plurality of injection nozzles (127) spaced apart along the first supply line (122).

[0183] The plurality of injection nozzles (127) may be installed on the wall of the first supply line (122) or at the end of a branch pipe branching from the first supply line (122).

[0184] The above-mentioned spray nozzles (127) are arranged at an angle facing each other so as to spray ozone-containing nanobubble water supplied through the first supply line (122) so as to collide or cross each other within the oxidation zone (111).

[0185] Accordingly, rotational flow and vortices can be formed in the oxidation region (111) by collision between ozone-containing nanobubbles.

[0186] Additionally, as an embodiment, the first supply line (122) may be provided with a vortex-forming injection module (126) including a plurality of injection nozzles (127), and the vortex-forming injection module (126) may be formed in a portion of the first supply line (122) (for example, the end portion of the first supply line that communicates with the ozone contact tank), and the plurality of injection nozzles (127) may be installed on the pipe wall of the first supply line (122) and configured to inject ozone-containing nanobubbles into the oxidation zone (111).

[0187] 6. Configuration of a rotary-driven air gap-controlled fiber filter

[0188] As shown in FIG. 6, the rotary drive type air gap control type fiber filter (130) includes a filter tank (131), a porous tube (132), a fiber filter material (133), and a drive unit (134).

[0189] The filtration tank (131) receives the oxidized treated water, i.e., the oxidized treated water, and provides a space in which the filtration process and backwashing process are performed.

[0190] An inlet (135) into which oxidized water is introduced may be formed on one side of the above-mentioned filtration tank (131). The inlet (135) is configured to allow the treated water oxidized in the ozone contact tank (110) to be introduced into the interior of the filtration tank (131).

[0191] The inlet (135) may be formed on the side or bottom side of the filtration tank (131) and may be formed so that the incoming treated water is supplied to the outer area of ​​the fiber filter material (133).

[0192] Accordingly, the oxidized water can be filtered as it moves from the outside to the inside of the fiber filter (133).

[0193] On the other side of the above-mentioned filtration tank (131), a discharge section (136) for discharging filtered treated water (i.e., filtered water) may be formed. The discharge section (136) may be connected to the interior of the porous tube (132) and may be formed so that filtered water flowing into the interior of the porous tube (132) through the fiber filter material (133) is discharged to the outside.

[0194] That is, during the filtration process, the treated water flows into the interior of the filtration tank (131) through the inlet (135), is filtered by the fiber filter material (133), flows into the interior of the porous tube (132) through the spray hole of the porous tube (132), and can be discharged to the outside through the discharge part (136).

[0195] Additionally, a backwash discharge section (137) for discharging contaminants and backwash wastewater removed during the backwashing process may be formed on one side or the lower side of the filter tank (131).

[0196] The above backwash discharge unit (137) is configured to allow fine oxide flux, suspended solids, sludge, and pollutants separated from the fiber filter material (133) during the backwash process to be discharged to the outside.

[0197] During the backwashing process, the treated water (backwash water) containing ozone-containing nanobubbles is sprayed from the inside of the porous tube (132) outward, and the contaminants attached to the fiber filter material (133) can be detached, and the detached contaminants can be moved to the backwash discharge section (137) by the internal flow of the filtration tank (131) and discharged to the outside.

[0198] Additionally, a backwash discharge valve may be additionally installed in the backwash discharge section (137), and the backwash discharge valve may be controlled to open during the backwash process and close during the filtration process.

[0199] If necessary, a flow stabilizing plate, a flow dispersion plate, or a turbulence suppression plate may be additionally installed inside the filtration tank (131), thereby allowing the treated water to be supplied more uniformly across the entire outer surface of the fiber filter material (133).

[0200] The treated water flowing into the interior of the filtration tank (131) through the above-mentioned inlet (135) may be oxidized water that has been oxidized by contacting ozone-containing nanobubbles in the ozone contact tank (110).

[0201] Specifically, the treated water can be supplied to the filtration tank (131) after an oxidation reaction occurs by contacting ozone-containing nanobubbles in the oxidation zone (111) and after fine oxidation flux is formed and retained in the retention zone (112).

[0202] Accordingly, the treated water flowing into the interior of the filtration tank (131) may contain fine oxidation flux, fine suspended matter, and oxidation reaction products, and the fiber filter material (133) can filter the treated water by capturing these fine oxidation flux and suspended matter.

[0203] The porous tube (132) is installed inside the filtration tank (131), has a hollow cylinder or cylinder shape, and has a plurality of spray holes (132A) formed through its surface. (Fig. 6 is a cross-sectional view to schematically explain an example of the fiber filter of the present invention.)

[0204] The porous tube (132) can function as a flow path through which filtered treated water (filtered water) is introduced during the filtration process, and during the backwashing process, it can function as a backwash water spraying section through which ozone-containing nanobubble water and oxidized treated water supplied through the recirculation line (140) are introduced into the interior and sprayed outward through the spray holes.

[0205] A plurality of fiber filter media (133) are installed radially on the outer side of the porous tube (132). The fiber filter media (133) may be formed of a plurality of fiber threads, fiber bundles, or fiber layers, and capture fine oxidation flux, suspended solids, and turbidity-causing substances in the treated water.

[0206] The driving unit (134) controls the operation so that the fiber filter material (133) is wound or unwound around the porous tube (132).

[0207] Specifically, the driving unit (134) may include a rotating filter holder connected to one side or the upper side of the fiber filter material (133), a rotary driving means connected to the rotating filter holder to rotate the rotating filter holder in one direction or the forward direction and in the other direction or the reverse direction, and the other side or the lower side of the fiber filter material (133) may be connected to a fixed member or a fixed filter holder.

[0208] In one embodiment, when the driving unit (134) rotates the rotating filter holder in one direction or a forward direction, the fiber filter material (133) is wound around the porous tube (132) to form a dense filter layer on the outer side of the porous tube (132). At this time, the gaps between the fiber filter material (133) are reduced, and the collection efficiency for fine oxidation flux and suspended matter is improved.

[0209] Conversely, when the driving unit (134) rotates the rotating filter holder in the opposite or reverse direction, the fiber filter material (133) can be unwound from a wound state or restored to its original state. At this time, the gaps between the fiber filter materials (133) can be expanded or repeatedly changed, and the captured contaminants become easy to detach.

[0210] Accordingly, the rotary drive type pore control fiber filter (130) can control the pore size between the fiber filter media (133) or the porosity of the filter layer by controlling the degree of winding or unwinding of the fiber filter media (133).

[0211] The structure or mutual coupling relationship of the above porous tube (132), fiber filter material (133), and driving unit (134), as well as the forward and reverse rotational operation relationship of the rotating filter material hanger and the operation relationship in which the fiber filter material (133) is wound or unwound on the porous tube (132) by the driving unit (134), etc., can be implemented by adopting the known technology disclosed in Patent Registration No. 10-2534889.

[0212] Below, an embodiment of the rotary drive type air gap control type fiber filter (130) of the present invention will be described in more detail.

[0213] The rotary drive type pore control fiber filter (130) of the present invention performs a filtration process through a filter layer (41) formed on the outside of a porous tube (132) by mounting a plurality of fiber filter media (133) in a multi-layer structure within a filter tank (131), and can control the size of the filter media pores or the porosity of the filter layer as desired by twisting the fiber filter media (133) by rotary drive control.

[0214] As shown in the drawing, the rotary drive type air gap control type fiber filter (130) of the present invention comprises a porous tube (132) installed inside a filtration tank (131), a filter media holder top plate (20) rotatably installed on the upper side of the porous tube (132), a filter media holder bottom plate (30) fixedly installed on the lower side of the porous tube (132), a plurality of fiber media (133) installed on the outside of the porous tube (132) and connected to the filter media holder top plate (20) and the filter media holder bottom plate (30), respectively, and a driving unit (134) having a rotary cylinder (50) installed on the upper side of the filtration tank (131) and connected to the filter media holder top plate (20) to rotate the filter media holder top plate (20).

[0215] The above-mentioned filtration tank (131) has a predetermined space inside and performs filtration and backwashing processes inside. A porous pipe (132) with a spray hole formed through the central part is installed upright and is connected to an inlet part (135) that introduces oxidized treated water (W0) into the filtration tank, and is connected to a backwash water discharge pipe (137) that discharges backwash water from the upper side.

[0216] The above porous pipe (132) is fixed inside the filtration tank (131) and installed upright, having a plurality of spray holes (132A) formed through it and a treated water discharge pipe (40) connected to the bottom.

[0217] Accordingly, during the filtration process, the oxidized treated water (W0) that has passed through the filter layer (41) passes through the spray holes of the porous tube (132) and flows into the porous tube (132), and is discharged to the outside through the treated water discharge pipe (40) as treated water (W1), i.e., filtered water. During the backwashing process, the backwash water (W2) that has flowed into the porous tube (132) through the backwash water inlet (160) passes through the spray holes of the porous tube (132) and flows into the filtration tank (131), and is discharged to the outside through the backwash water discharge pipe (137) on the upper side of the filtration tank (131).

[0218] In the rotary drive type air gap control fiber filter (130) of the present invention, a filter media holder top plate (20) is rotatably installed on the upper side of the porous tube (132), and a filter media holder bottom plate (30) is fixedly installed on the lower side of the porous tube (132) to form the lower surface of the filter tank (131).

[0219] The driving unit (134) of the rotary drive type air gap control fiber filter (130) of the present invention comprises a rotary cylinder (50) installed on the upper part of the filter tank (131) and a rotary shaft (51) connected to the rotary cylinder (50).

[0220] The filter holder top plate (20) is connected to a rotary cylinder (50) and a rotary shaft (51) and configured to rotate by the rotational drive of the rotary cylinder (50). Various known technologies may be adopted for the coupling structure between the rotary cylinder (50) that rotates the filter holder top plate (20) and the filter holder top plate (20), and the drive control of the rotary cylinder (50) is implemented by a control means (not shown) provided in the drive unit (134), and known technologies may be adopted.

[0221] As shown in the illustration, the lower plate (30) of the above filter holder is penetrated by an oxidation treatment water inlet pipe (138) and a treatment water discharge pipe (139), so that the oxidation treatment water inlet pipe (138) is connected to the filtration tank (131) and the treatment water discharge pipe (139) is connected to the porous pipe (132).

[0222] The fiber filter material (133) of the present invention is connected to the upper plate (20) and the lower plate (30) of the filter material holder on the outside of the porous tube (132) and is installed in multiple numbers. As illustrated, multiple fiber filter materials are installed in a multi-layer structure in which the length becomes shorter as they go toward the porous tube (132), that is, toward the inside. The reason the length of the fiber filter material becomes shorter toward the inside is that when the upper plate (20) of the filter material holder rotates and twists the fiber filter material, the circumference or arc length of the fiber filter material located on the outside is longer than that of the fiber filter material located on the inside.

[0223] In addition, as the fiber filter material (133) of the present invention has a multilayer structure as shown (in one embodiment, it is shown as a three-layer structure in the attached drawings), a denser filter layer (41) is formed when the fiber filter material is twisted.

[0224] Meanwhile, the fiber filter material (133) of the present invention may be composed of a bundle of known fiber yarns that serve as a filter material.

[0225] As a preferred embodiment of the present invention, the fiber filter material (133) can have its upper and lower ends connected to the upper plate (20) and the lower plate (30) of the filter holder, respectively, through a filter ring (70) as shown in the illustrated drawing.

[0226] In the upper plate (20) of the filter holder of the present invention, as shown in the attached drawing, a plurality of connecting holes (21) are formed so that a filter ring (70) can pass through and be connected, and in the lower plate (30) of the filter holder of the present invention, a plurality of connecting holes (31) are formed so that a filter ring (70) can pass through and be connected.

[0227] To explain more specifically, as illustrated, the upper part of the fiber filter material (133) is connected over the filter material ring (70), and then the filter material ring (70) is passed through the coupling hole (21) of the filter material hanger top plate (20), and then the filter material ring (70) is fastened to the filter material hanger top plate (20) through the fastener (71), so that the upper part of the fiber filter material (133) is connected to the filter material hanger top plate (20).

[0228] In the same way, as illustrated, the lower part of the fiber filter material (133) is connected across the filter material ring (70), and then the filter material ring (70) is passed through the coupling hole (31) of the filter material hanger bottom plate (30), and then the filter material ring (70) is fastened to the filter material hanger bottom plate (30) through the fastener (71), so that the lower part of the fiber filter material (133) is connected to the filter material hanger bottom plate (30).

[0229] In a preferred embodiment, the filter ring (70) may have a known U-bolt shape that can penetrate a pair of adjacent connecting holes (21, 31) in the upper plate (20) and the lower plate (30) of the filter rack, and the fastener (71) may be a nut that is fastened only to one side of the filter ring (70) having the U-bolt shape.

[0230] Accordingly, the fiber filter material (133) can be connected to the upper plate (20) and the lower plate (30) of the filter holder by connecting the upper and lower parts of the fiber filter material (133) to the filter holder ring (70) respectively through the connecting holes (21, 31).

[0231] When the above fiber filter material (133) is connected to the upper plate (20) and the lower plate (30) of the filter material hanger, and the upper plate (20) of the filter material hanger is rotated by the driving of a rotary cylinder (50) controlled by the control means of the driving unit (134), a plurality of fiber filter materials (133) having a multi-layer structure are twisted to form a filter layer (41) as shown in the illustrated drawing.

[0232] In the present invention, the lower plate (30) of the filter media holder is fixedly installed, while the upper plate (20) of the filter media holder rotates by the driving of a rotary cylinder (50) to twist the fiber filter media (133). The rotary cylinder (50) is a known actuator connected to a rotation shaft (51) to rotate the rotation shaft (51) and the upper plate (20) of the filter media holder. As a preferred embodiment of the present invention, the rotary cylinder (50) may have the configuration of a known rotary cylinder that utilizes pneumatic pressure.

[0233] Additionally, as a preferred embodiment, the air pressure supplied to the rotary cylinder (50) or the rotation angle of the rotary cylinder (50) can be controlled through a driving unit (134) equipped with a limit sensor (61).

[0234] In other words, the rotation angle of the rotating shaft (50) connected to the rotary cylinder (50) or the top plate (20) of the filter media holder, that is, the degree to which the fiber media (133) is twisted or the angle at which the fiber media is twisted and rotated, can be adjusted using a limit sensor (61) or a limit switch.

[0235] In one embodiment, the limit sensor (61) is a known limit sensor that can be applied to a method of blocking the supplied air when the rotation shaft (50) rotates to a set rotation angle. Additionally, the rotation angle of the filter holder top plate (20) can be set by the device operator in various ways through a rotation angle setting unit (not shown) provided in the driving unit (134).

[0236] Additionally, the driving unit (134) further comprises a pneumatic setting unit (62) so that the air pressure supplied to the rotary cylinder (50) can be adjusted according to the pneumatic setting of the device operator through the pneumatic setting unit (62), thereby allowing the twisting force applied to the fiber filter material (133) to be adjusted.

[0237] Accordingly, the device of the present invention can control the size of the voids formed between the fiber filter media or the porosity of the filter layer by controlling the angle at which the fiber filter media is twisted and rotated or by controlling the twisting force applied to the fiber filter media (133) through the control of the rotary cylinder (50).

[0238] In other words, the present invention allows for the filtration process or backwashing process to be performed while controlling the size of the pores formed between the fiber filter media or the porosity of the filter layer as desired.

[0239] Of course, the rotation of the rotation shaft (51) connected to the rotary cylinder (50) through the above drive unit (134) in one direction and the other direction can be controlled as desired according to the rotation direction setting of the device operator.

[0240] Now, the present invention will be described again in detail while explaining the process of operating the present invention.

[0241] In the filtration process of the present invention, first, the rotation angle of the filter media holder top plate (20) or the twisting angle of the fiber filter media (133) is set through the control of the driving unit (134), and the pneumatic pressure supplied to the rotary cylinder (50) is set through the pneumatic pressure setting unit (62). When the device is started, the oxidized water (W0) flows into the filtration tank (131) through the oxidized water inlet pipe (138), and at the same time, the filter media holder top plate (20) rotates in one direction by a set rotation angle by the driving of the rotary cylinder (50), so that the fiber filter media (133) is wound around the porous tube (132), and a filter layer (41) is formed on the outer side of the porous tube (132). At this time, the force for twisting the fiber filter media (133) is determined according to the set pneumatic pressure supplied to the rotary cylinder (50).

[0242] Afterwards, the oxidized water (W0) introduced into the filtration tank (131) is filtered by the filter layer (41) and then introduced into the porous tube (132), and the treated water (W1) introduced into the porous tube (132) is discharged to the outside as filtered water through the treated water discharge pipe (139).

[0243] During the backwashing process of the present invention, the upper plate of the filter media holder (20) is driven by the driving of the rotary cylinder (50) and, under the control of the driving unit (134), the upper plate of the filter media holder (20) is repeatedly rotated in one direction (or clockwise rotation) and in the other direction (or counterclockwise rotation), and the process of the fiber filter media (133) being wound around the porous tube (132) and restored is repeated, and the backwash water (W) introduced into the interior of the porous tube (132) through the backwash water inlet (160) is discharged to the outside of the porous tube (132), and at the same time, backwash air (G) is sprayed toward the fiber filter media (133) from the bottom of the filtration tank (131).

[0244] First, the device of the present invention can be controlled to perform backwashing or backwashing while restoring the fiber filter material (133) to its original, untwisted state through the driving unit (134) during the backwashing process, or to perform backwashing or backwashing while repeatedly rotating the fiber filter material (133) in clockwise and counterclockwise directions.

[0245] In addition, during the backwashing process, the backwashing air (G) is configured to be sprayed directly below the lower part of the fiber filter material (133), so that backwashing or backwashing of the fiber filter material (133) by the backwashing air (G) can be performed very effectively.

[0246] To explain this more specifically, as illustrated, a plurality of connecting holes (21, 31) are formed in the upper plate (20) and the lower plate (30) of the filter holder, and a plurality of backwash air injection holes (32) are further formed in the lower plate (30) of the filter holder. In a preferred embodiment, the backwash air injection holes (32) may be formed between a pair of connecting holes (31) of the lower plate of the filter holder.

[0247] As a result, when the lower part of the fiber filter material (133) is connected to the lower plate (30) of the filter holder through the filter material ring (70), the backwash air injection hole (32) can be positioned directly below the lower part of the fiber filter material (133), and as illustrated, backwash air (G) is directly injected toward the lower part of the fiber filter material (133), so the backwash (removal) effect of the fiber filter material (133) by the backwash air (G) is greatly improved.

[0248] Backwash air (G) may be introduced into the device through the backwash air inlet pipe (80) and sprayed through the backwash air injection hole (32) of the lower plate (30) of the filter media holder, or backwash air supplied from a backwash air injection nozzle (not shown) provided on the lower side of the filter tank (131) or the lower side of the lower plate (30) of the filter media holder may be sprayed through the backwash air injection hole (32).

[0249] In addition, as a preferred embodiment of the present invention, an overflow inducing wall (171) is provided on the upper inner side of the filtration tank (131) to form an overflow water path (170) along the inner circumference of the filtration tank.

[0250] The above-mentioned overflow guide wall (171) guides water that has risen above a predetermined water level inside the filtration tank (100), that is, water that has overflowed the above-mentioned overflow guide wall (171), to be discharged through the overflow flow path (170) to the backwash water discharge pipe (137).

[0251] When a backwash water discharge pipe (137) is provided on one side of the upper portion of the filtration tank (131), the backwash water on the opposite side (other side) is relatively difficult to discharge through the backwash water discharge pipe (137) because it is on the opposite side. Therefore, in order to solve this problem, the present invention forms an overflow water channel (170) that communicates with the backwash water discharge pipe (137) along the inner circumference of the upper portion inside the filtration tank (131), so that even if the backwash water is on the opposite side of the backwash water discharge pipe (137), it can be smoothly discharged to the backwash water discharge pipe (137) through the overflow water channel (170) simply by overflowing the overflow guide wall (171).

[0252] Accordingly, by forming the overflow inducing wall (171) and the overflow flow path (170), the backwash water (W2) is smoothly and quickly discharged from inside the filtration tank (131) to the backwash water discharge pipe (137).

[0253] 7. Filtration Process

[0254] During the filtration process, the oxidized water that has passed through the oxidation zone (111) and retention zone (112) of the ozone contact tank (110) is discharged through the side discharge section (113) and supplied into the filtration tank (131) of the rotary drive type pore control fiber filter (130).

[0255] The driving unit (134) can control the fiber filter material (133) to be wound around the porous tube (132). Accordingly, the fiber filter material (133) forms a dense filter layer while wound around the outside of the porous tube (132). (Drawing of the filter layer is omitted)

[0256] Oxidized water is filtered as it passes through the filter layer. During this process, fine oxidation flux, suspended solids, turbidity-causing substances, and residual particles in the treated water are collected in the fiber filter material (133).

[0257] The filtered treated water, i.e., the filtered water, flows into the interior of the porous tube (132) through the spray hole (132A) of the porous tube (132), and then is discharged as reusable water through the treated water discharge line (not shown) via a reusable water storage tank or a subsequent treatment process.

[0258] In the present invention, the ozone contact tank (110) oxidizes and converts pollutants in the discharge water into fine oxidation flux, and the rotary drive type pore control fiber filter (130) effectively captures the fine oxidation flux through a dense filter layer.

[0259] The control unit (150) of the present invention controls the filtration process and backwashing process of the rotary drive type air gap control type fiber filter (130).

[0260] The above control unit (150) is electrically connected to the driving unit (134) and can control the driving direction, rotation angle, rotation speed, number of reciprocating rotations, and driving time of the driving unit (134).

[0261] During the filtration process, the control unit (150) can control the driving unit (134) to cause the fiber filter material (133) to be wound in a predetermined direction (one direction or forward direction and another direction or reverse direction) around the porous tube (132). Accordingly, a filter layer with reduced pores of the fiber filter material (133) can be formed.

[0262] During the backwashing process, the control unit (150) can open the recirculation control valve (143) and control the drive unit (134) to cause the fiber filter material (133) to repeatedly wind and unwind around the porous tube (132).

[0263] The above control unit (150) can determine the start and end of the backwashing process based on the ozone sensor (145), the flow sensor (146), and, if necessary, at least one sensor signal among the pressure sensor, the turbidity sensor, and the differential pressure sensor.

[0264] 8. Configuration of the recirculation line

[0265] The recirculation line (140) includes an intake end (141), a supply end (142), a recirculation control valve (143), an ozone sensor (145), and a flow sensor (146).

[0266] The intake unit (141) is connected to the side discharge unit (113) of the ozone contact tank (110). Accordingly, a portion of the supernatant water or oxidized treated water (oxidized treated water) from the retention area (112) can be taken to the recirculation line (140).

[0267] The supply section (142) is connected to the interior of the porous tube (132) of the rotary-driven pore-controlled fiber filter (130). Accordingly, the ozone and nanobubble-containing treated water (or treated water containing ozone-containing nanobubbles) transported through the recirculation line (140) can be supplied into the interior of the porous tube (132).

[0268] The recirculation control valve (143) is opened during the backwashing process. During the filtration process, the recirculation control valve (143) may be closed.

[0269] A recirculation pump (144) may be installed in the recirculation line (140). The recirculation pump (144) serves to pump treated water taken from the side discharge section (113) of the ozone contact tank (110) into the porous pipe (132).

[0270] The above recirculation control valve (143) and recirculation pump (144) can be controlled by the control unit (150).

[0271] 9. Backwashing process

[0272] During the backwashing process, the control unit (150) opens the recirculation control valve (143). Accordingly, a portion of the oxidized treated water, which is the supernatant of the retention area (112), is supplied from the side discharge unit (113) of the ozone contact tank (110) into the porous tube (132) of the rotary drive type pore control fiber filter (130) through the recirculation line (140).

[0273] Additionally, ozone-containing nanobubble water generated from the nanobubble generator (121) is supplied to the recirculation line (140) through the second supply line (123). Thus, the backwash water supplied into the porous tube (132) may contain ozone and nanobubbles.

[0274] During the backwashing process, the driving unit (134) drives the fiber filter material (133) so that the operation of winding and unwinding around the porous tube (132) is repeated. That is, the driving unit (134) can alternately rotate one side of the fiber filter material (133) in one direction and the other direction so that the fiber filter material (133) can repeatedly be wound along the outer circumference of the porous tube (132) and unwound.

[0275] The repetition of such winding and unwinding repeatedly changes the gaps between the fiber filter media (133) and is advantageous for detaching fine oxide flux, sticky contaminants, biofilms, and suspended matter captured in the fiber filter media (133).

[0276] At the same time, the oxidation treatment water containing ozone and nanobubbles and the nanobubble water are supplied into the porous tube (132) through the recirculation line (140) as backwash water and sprayed outwardly through the spray holes of the porous tube (132).

[0277] The above backwash water performs a water pressure cleaning action that pushes out captured contaminants as it passes through the fiber filter material (133) from the inside to the outside.

[0278] In addition, ozone contained in the backwash water can oxidize and decompose organic pollutants, adhesive pollutants, or biofilm components attached to the fiber filter material (133), and nanobubbles can penetrate into the fine pores between the fiber filter material (133) to cause micro-distancing, reduce adhesion, and promote detachment.

[0279] Accordingly, in the backwashing process of the present invention, changes in pores due to the repeated winding and unwinding of the fiber filter material (133), backwash water spraying from the inside to the outside through the spray hole (132A) of the porous tube (132), oxidative cleaning by ozone, and fine cleaning action by nanobubbles act in combination.

[0280] In the backwashing process of the present invention, the backwash water supplied through the recirculation line (140) may basically be a mixture of ozone nanobubble-containing oxidation treatment water supplied from the ozone contact tank (110) and ozone-containing nanobubble water supplied from the second supply line (123).

[0281] 10. Control of nanobubble supply amount by ozone sensor

[0282] An ozone sensor (145) for detecting residual ozone concentration is installed in the recirculation line (140).

[0283] The ozone sensor (145) detects the residual ozone concentration of the backwash water flowing through the recirculation line (140) during the backwash process. The control unit (150) receives the detection value of the ozone sensor (145).

[0284] When residual ozone below a set concentration is detected by the ozone sensor (145), the control unit (150) controls the supply amount of the nanobubble supply unit (120) to increase.

[0285] For example, the control unit (150) can increase the driving output of the nanobubble generator (121), increase the driving output of the supply pump (124) installed in the second supply line (123), or increase the opening rate of the flow control valve (125) installed in the second supply line (123).

[0286] Accordingly, the ozone and nanobubble content of the backwash water supplied into the porous tube (132) through the recirculation line (140) can be enhanced.

[0287] This control ensures that even when the residual ozone concentration decreases due to changes in the pollution load of the discharge water, ozone consumption, the degree of contamination of the fiber filter material (133), or backwash conditions, the oxidative cleaning power during the backwash process is maintained at a certain level or higher.

[0288] 11. Recirculation control valve control by flow sensor

[0289] A flow sensor (146) is installed in the recirculation line (140). The flow sensor (146) detects the recirculation flow rate of the backwash water flowing through the recirculation line (140) during the backwash process. The control unit (150) receives the detection value of the flow sensor (146).

[0290] When the recirculation flow rate decreases below a set value during the backwashing process, the control unit (150) controls the recirculation control valve (143) to open further.

[0291] A decrease in the recirculation flow rate may occur due to an increase in the degree of clogging of the fiber filter material (133), an increase in the load of the injection holes of the porous pipe (132), an increase in the pressure loss of the recirculation line (140), or a lack of backwash water supply.

[0292] In this case, the backwash water flow rate supplied into the porous tube (132) can be compensated by the control unit (150) further opening the recirculation control valve (143). If necessary, the control unit (150) may also increase the driving output of the recirculation pump (144).

[0293] In this specification, "recirculation flow rate" or "backwash flow rate" may refer to the flow rate of backwash water supplied into the porous tube (132) of the rotary-driven porous-controlled fiber filter (130) through the recirculation line (140).

[0294] The above backwash water may include oxidized water discharged from the ozone contact tank (110) and ozone-containing nanobubble water supplied from the nanobubble supply unit (120), and the recirculation flow rate may be detected by a flow sensor (146).

[0295] The case where the backwash water flow rate is reduced may mean a state in which the flow rate of backwash water supplied through the recirculation line (140) is reduced to a standard flow rate or lower due to blockage of part of the recirculation line (140), recirculation control valve (143), porous pipe (132), or injection hole, or an increase in flow resistance.

[0296] In addition, the reduction in the backwash water flow rate may occur due to insufficient opening of the recirculation control valve (143), accumulation of scale or foreign matter inside the pipe, or blockage of the injection holes of the porous pipe (132).

[0297] When the backwash water flow rate detected by the above flow sensor (146) decreases to a level below a set reference flow rate, the control unit (150) can control the backwash efficiency to be maintained by increasing the opening amount of the recirculation control valve (143) or adjusting the supply amount of the nanobubble supply unit (120).

[0298] 12. Effects of the present invention

[0299] According to the present invention, ozone and nanobubbles are supplied in the oxidation zone (111) of the ozone contact tank (110) to oxidize and treat pollutants in the discharge water.

[0300] Additionally, the micro-oxidation flux is retained and stabilized for a certain period of time in the retention area (112), and the stabilized supernatant is supplied to the rear fiber filter (130) through the side discharge section (113).

[0301] The above-mentioned residence area (112) is formed downstream of the oxidation area (111) and is a space that allows the fine oxidation flux generated in the oxidation area (111) to stay for a certain period of time to grow and stabilize.

[0302] In the oxidation region (111), organic pollutants, color-causing substances, colloidal substances, and fine suspended particles can be oxidized as ozone-containing nanobubbles come into contact with the discharge water. In this process, the oxidation products generated by the oxidation reaction and the fine suspended particles can combine with each other to form fine oxidation flux.

[0303] However, the fine oxidation flux immediately after exiting the oxidation region (111) has a very small particle size and weak binding force, so if it is immediately introduced into the fiber filter (130), the filtration efficiency may be reduced. Therefore, the retention region (112) can be formed so that the fine oxidation flux can remain for a certain period of time and collide and aggregate with one another.

[0304] In the above retention area (112), the flow rate of the treated water may be reduced compared to the oxidation area (111). Accordingly, the micro-oxidation flux may repeatedly come into contact with Brownian motion, gravity sedimentation, fluid collision, and vortex residual energy.

[0305] In this process, the fine oxide fluxes can aggregate with each other and grow into larger fluxes. Accordingly, the collection efficiency of the fiber filter (130) can be improved.

[0306] The above retention area (112) can perform not only simple aggregation but also flux stabilization functions. That is, the flux formed in the oxidation area (111) can be easily dispersed or destroyed in a strong turbulent environment, but since the flow velocity is mitigated in the retention area (112), the redispersion of the flux can be suppressed. Accordingly, the formed flux can maintain a more stable structure and can be maintained in a state suitable for capture in the fiber filter (130).

[0307] As the flux grows in the retention area (112), flux with a relatively high density may be concentrated in the middle or lower layer. On the other hand, treated water with a relatively low flux concentration may be formed in the upper area. The upper treated water formed in this way may be referred to as supernatant water in the present invention. The lateral discharge section (113) may be formed to collect the supernatant water according to known technology, thereby preventing the inflow of excessive sludge or flux concentration areas.

[0308] Accordingly, the above retention area (112) can simultaneously secure additional reaction time between ozone-containing nanobubbles and treated water, grow fine oxidation flux, stabilize flux, form supernatant water, and improve the filtration efficiency of the downstream fiber filter.

[0309] Accordingly, the present invention can simultaneously improve oxidation treatment efficiency and filtration treatment efficiency by placing a retention area (112) between the oxidation area (111) and the fiber filter (130).

[0310] In addition, the rotary drive type air gap control fiber filter (130) forms a dense filter layer (or filter layer) by winding the fiber filter material (133) to effectively capture fine oxidation flux and suspended matter.

[0311] In addition, during the backwashing process, a portion of the oxidized water treated in the ozone contact tank (110) is recycled as backwash water through the recirculation line (140), and additional nanobubbles are supplied through the second supply line (123), so the backwash water itself functions as oxidized cleaning water containing ozone and nanobubbles.

[0312] In addition, during the backwashing process, the fiber filter material (133) is repeatedly wound and unwound around the porous tube (132), so the pores of the fiber filter material (133) change repeatedly, and fine oxide flux and contaminants captured in the fiber filter material (133) can be easily removed.

[0313] In addition, since backwash water is sprayed from the inside to the outside through the spray holes of the porous tube (132), contaminants collected during the filtration process can be effectively discharged in a direction opposite to the filtration direction.

[0314] In the present invention, the oxidized treated water containing ozone-containing nanobubbles may refer to treated water in which ozone-containing nanobubbles are included in the treated water that has been oxidized by contacting the discharge water with ozone-containing nanobubbles in the oxidation zone (111) of the ozone contact tank (110). This oxidized treated water containing ozone-containing nanobubbles is supplied to a rotary-driven pore-controlled fiber filter (130) through a recirculation line (140) and can be used as backwash water for cleaning the fiber filter material (133) during the backwash process.

[0315] In addition, the residual ozone concentration is detected by the ozone sensor (145), and the nanobubble supply amount is controlled to increase when the residual ozone concentration is below the set concentration, thereby stably maintaining the oxidative cleaning power of the backwash process.

[0316] In addition, the recirculation flow rate is detected by the flow sensor (146), and when the recirculation flow rate decreases below a set value, the recirculation control valve (143) is controlled to open further, thereby ensuring a sufficient backwash flow rate during the backwash process.

[0317] Accordingly, the present invention can provide a wastewater reuse treatment system in which the oxidation treatment of wastewater, stabilization of micro-oxidation flux, fibrous filter media filtration, ozone and nanobubble recirculation backwashing, and sensor-based control are organically combined.

[0318] In addition, as an embodiment of the present invention, a flux stabilization coating layer may be formed on the surface of the baffle plate (114) to promote the retention, aggregation, and stabilization of fine oxidation flux.

[0319] The above flux stabilization coating layer may be a layer that imparts surface roughness or surface charge characteristics to suppress the rapid movement of fine oxidation flux in the oxidation treatment water along the surface of the baffle plate (114) and to promote collision and aggregation between fine oxidation fluxes.

[0320] The flux-stabilizing coating layer may include inorganic oxides, ceramics, zeolites, activated carbon, silica, alumina, titania, iron oxide, manganese oxide, or a mixture thereof.

[0321] In addition, the flux stabilization coating layer may include one or more of a hydrophilic polymer, a cationic polymer, anionic polymer, or an amphoteric polymer, and may promote the aggregation and stabilization of the microoxidation flux through electrostatic interaction or hydrogen bonding with the microoxidation flux.

[0322] The above flux stabilization coating layer can be formed on one or both sides of the baffle plate (114), and can be formed on the surface of the uneven portion of the baffle plate (114) to simultaneously improve the flow disturbance of the treated water and the retention effect of the fine oxidation flux.

[0323] Accordingly, the fine oxidation flux formed in the oxidation zone (111) can aggregate and grow while staying near the surface of the baffle plate (114) for a certain period of time or repeatedly colliding during the process of moving to the retention zone (112), and can be stabilized in a state suitable for capture by the rear rotary drive type pore control fiber filter (130).

[0324] It is preferable that the above flux stabilization coating layer be formed as a fixed coating layer on the surface of the baffle plate (114) so ​​as not to be excessively leached into the oxidizing treatment water. Explanation of the symbols

[0325] 110: Ozone contact tank, 111: Oxidation zone, 112: Retention zone, 113: Side discharge section, 114: Baffle plate, 120: Nanobubble supply section, 121: Nanobubble generator, 122: First supply line, 123: Second supply line, 126: Vortex-forming injection module, 127: Injection nozzle, 130: Rotary-driven air gap-controlled fiber filter, 131: Filter tank, 132: Porous tube, 133: Fiber filter media, 134: Drive unit, 140: Recirculation line, 141: Intake unit, 142: Supply end, 143: Recirculation control valve, 145: Ozone sensor, 146: Flow sensor, 150: Control unit

Claims

Claim 1 In a wastewater reuse treatment system, an ozone contact tank (110) for oxidizing wastewater; a nanobubble supply unit (120) for supplying ozone-containing nanobubble water to the ozone contact tank (110); and a rotary drive type pore control fiber filter (130) disposed at the rear end of the ozone contact tank (110) for filtering the oxidized treated water discharged from the ozone contact tank (110). The ozone contact tank (110) and the rotary-driven pore-controlled fiber filter (130) are connected, and during the backwashing process of the rotary-driven pore-controlled fiber filter (130), the ozone-treated water discharged from the ozone contact tank (110) and ozone-containing nano-bubble water supplied from the nano-bubble supply unit (120) are supplied as backwash water to the rotary-driven pore-controlled fiber filter (130), and the ozone contact tank (110) includes an oxidation zone (111) in which the incoming discharge water and ozone-containing nano-bubble water are mixed to perform an oxidation reaction on the discharge water and a fine oxidation flux is formed by the oxidation reaction, a retention zone (112) formed downstream of the oxidation zone (111) to retain the fine oxidation flux for a predetermined time to coagulate and stabilize it, and a side zone for discharging the supernatant water of the retention zone (112). The nanobubble supply unit (120) includes a discharge unit (113), and the nanobubble supply unit (120) includes a nanobubble generator (121) that generates ozone-containing nanobubble water, a first supply line (122) that connects the ozone contact tank (110) and the nanobubble supply unit (120) and supplies the ozone-containing nanobubble water generated from the nanobubble generator (121) to the oxidation zone (111), and a second supply line (123) that connects the nanobubble supply unit (120) and the recirculation line (140) and supplies the ozone-containing nanobubble water generated from the nanobubble generator (121) to the recirculation line (140). The rotary drive type pore control type fiber filter (130) includes a porous tube (132) that is installed inside the filter tank (131) and has a plurality of spray holes (132A) formed through it, and a rotary on the upper side of the porous tube (132). A filter holder top plate (20) that can be installed, andThe apparatus comprises a filter media holder bottom plate (30) fixedly installed on the lower side of the porous tube (132), a plurality of fiber filter media (133) installed in a multi-layer structure that is connected to the filter media holder top plate (20) and the filter media holder bottom plate (30) respectively on the outer side of the porous tube (132) and becomes shorter in length as it goes inward between the filter media holder top plate (20) and the filter media holder bottom plate (30), and a driving unit (134) that is connected to the filter media holder top plate (20) and rotates the filter media holder top plate (20) by means of a rotary cylinder (50) installed on the upper side of the filtration tank (131), and during the filtration process, the filter media holder top plate (20) rotates in one direction by the driving of the rotary cylinder (50), and the fiber filter media (133) is wound around the porous tube (132) and on the outer side of the porous tube (132) A filter layer (41) is formed, and the oxidized water flowing into the interior of the filtration tank (131) is filtered by the filter layer (41) and then flows into the porous tube (132) and discharged. During the backwashing process, the upper plate (20) of the filter media holder is driven by the rotary cylinder (50) to repeatedly rotate in one direction and in the other direction, and the process of the fiber filter media (133) being wound around the porous tube (132) and restored is repeated, while the backwash water flowing into the interior of the porous tube (132) is discharged to the outside of the porous tube (132), and at the same time, backwash air is sprayed from the bottom of the filtration tank (131) toward the fiber filter media (133). A plurality of coupling holes (21, 31) are formed in the upper plate (20) and the lower plate (30) of the filter media holder, respectively, and a plurality of backwash air injection holes (32) are further formed in the lower plate (30) of the filter media holder. The fiber filter material (133) is connected to the upper plate (20) and the lower plate (30) of the filter holder, respectively, through the filter material ring (70), and the filter material ring (70) is fastened to the upper plate (20) and the lower plate (30) of the filter holder, respectively, through the coupling holes (21, 31), and the backwash air injection hole (32) is located directly below the fiber filter material connected to the filter material ring (70) fastened to the lower plate (30) of the filter holder, and the recirculation line (140) isThe apparatus includes a intake end (141) connected to a side discharge part (113) of the ozone contact tank (110), a supply end (142) connected to the inside of a porous tube (132) of the rotary drive type porous control fiber filter (130), and a recirculation control valve (143) that opens during a backwashing process. During a backwashing process, the oxidation treatment water and ozone-containing nanobubble water are combined in the recirculation line (140), and the backwash water composed of the oxidation treatment water and ozone-containing nanobubble water is supplied into the porous tube (132) through the recirculation line (140) and sprayed outwardly through the spray hole (132A) to clean the fiber filter material (133) placed on the outside of the porous tube (132) from the inside outward direction. An ozone sensor (145) for detecting ozone concentration is installed in the recirculation line (140). A discharge water reuse treatment system using a rotary drive type pore control type fiber filter, characterized in that when the residual ozone concentration in the recirculation line (140) is detected to be below a set concentration by the ozone sensor (145), the control unit (150) controls the supply amount of ozone-containing nanobubble water supplied from the nanobubble supply unit (120) to increase, and a flow sensor (146) is installed in the recirculation line (140), and when the flow rate of backwash water detected by the flow sensor (146) during the backwash process decreases to below a set value, the control unit (150) controls the recirculation control valve (143) to open further. Claim 2 delete Claim 3 delete

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