Ozone catalytic oxidation wastewater treatment system

Abstract

The utility model provides a catalytic ozonation wastewater treatment system, which comprises a pre-reactor, a main reactor, an ozone generator and a gas dissolver, the pre-reactor and the main reactor are sequentially communicated along the wastewater input direction, an ozone dissolved gas release area is arranged in the main reactor, the ozone generator is communicated with the gas dissolver and is used for providing ozone for the gas dissolver, and the ozone generator is communicated with the gas dissolver. The air dissolver is respectively communicated with the upper part of the main reactor and the ozone dissolved air release area, and is used for receiving the treated water in the main reactor as dissolved air water, and inputting ozone into the ozone dissolved air release area to form micro-nano bubbles to enter the main reactor to oxidize organic matters in the wastewater. According to the catalytic ozonation wastewater treatment system provided by the utility model, micro-nano ozone bubbles can be generated by utilizing ozone, the emission of ozone in tail gas is reduced, and the catalytic ozonation wastewater treatment system is high in wastewater treatment capacity and suitable for wastewater treatment of various scales.

Description

Technical Field

[0001] The utility model belongs to the technical field of wastewater treatment and relates to an ozone catalytic oxidation wastewater treatment system, specifically to an ozone catalytic oxidation wastewater treatment system based on the release of dissolved gas to generate micro-nano bubbles. The utility model can be applied to the treatment of various types of difficult-to-biodegrade industrial wastewater, and is particularly suitable for deep treatment of wastewater in wastewater reuse or zero-discharge wastewater treatment projects. Background Art

[0002] Ozone catalytic oxidation technology, as a type of advanced oxidation technology, is widely used in industrial wastewater treatment and deep wastewater treatment. Due to the low solubility of ozone (the solubility of ozone in water at room temperature and pressure is only about 10 mg / L) and the limitation of redox potential (2.07V), the direct oxidation technology using ozone has a slow reaction rate, and its oxidation reaction rate constant is often only 1-10 3 M -1 S -1 , and the reaction is selective; due to the dipolar, electrophilic, and nucleophilic properties of ozone molecules, the direct oxidation mechanism of ozone includes three mechanisms: Criegree mechanism, electrophilic reaction mechanism, and nucleophilic reaction mechanism. On the other hand, in the presence of transition metal ions or oxide catalysts, ozone undergoes an indirect reaction (i.e., ozone catalytic oxidation reaction). At this time, ozone forms hydroxyl radicals (·OH) in water, whose redox potential reaches 2.8V. ·OH acts as a secondary oxidant to rapidly oxidize organic matter, and the oxidation reaction rate reaches 10 8 -10 10 M -1 S -1 The oxidation efficiency is significantly higher than that of direct ozone oxidation. Furthermore, this reaction is non-selective and instantaneous, capable of oxidizing any reducing organic matter. The reaction mechanism between OH and organic matter primarily involves dehydrogenation, electrophilic addition, and electron transfer. Although the efficiency of indirect ozone catalytic oxidation is significantly higher than that of direct ozone oxidation, its actual efficiency is still affected by numerous factors, including ozone concentration, contact surface area, ozone utilization efficiency, catalyst type, contact reaction method and duration, pH, and temperature.

[0003] Currently available ozone catalytic oxidation reaction devices adopt two catalytic reaction modes: homogeneous and heterogeneous.

[0004] The ozone catalytic oxidation reaction devices disclosed in Chinese patents CN 220034188 U, CN 219860802 U, CN 219730663 U, CN 117756266 A, and CN 117682652A all utilize homogeneous reaction systems, requiring continuous top-up addition of catalyst. Ozone is added using perforated tubes or microporous aeration heads, and a stirring device or airlift internal circulation device is installed within the reaction tank. CN 117682652 A also utilizes a ceramic membrane to recover and recycle the catalyst. It also incorporates a two-stage ozone catalytic oxidation system, with ozone added in the first stage using a jet micro-nano generator in the form of micro-nano bubbles, and in the second stage using a conventional aeration tube. These homogeneous reaction systems have a stirring system but no fixed catalyst bed, so the reaction mixing is relatively uniform, the reaction efficiency is relatively high, and the size of the equipment is relatively small. However, continuous addition of catalyst or catalyst separation is required, and there is a relatively high level of residual ozone in the reaction exhaust gas, which needs to be eliminated by an ozone destructor before it can be discharged.

[0005] Chinese patents CN 220098714 U, CN 219950661 U, CN 219907203 U, CN 219860806 U, CN 219839561 U, CN 219670253 U, CN 219567692 U, and CN 219297261 U disclose single-stage heterogeneous reaction systems. In these systems, ozone is introduced from the bottom using micropores, air distribution pipes, or ejectors, while wastewater is added from the bottom or top. Within the reactor, ozone is enhanced in contact with wastewater and catalyst by installing a catalyst agitator above the filter bed (CN 220098714 U), a stirring circulation tank (CN 219950661 U, CN 219907203 U, CN 219860806 U), or membrane aeration (CN 219567692 U), thereby improving reaction efficiency. These reactors are generally large, requiring long residence times for the reaction. The tail gas contains high ozone concentrations, requiring ozone removal by an ozone destructor before discharge.

[0006] Some Chinese patents disclose some two-stage or multi-stage heterogeneous reaction systems, such as Chinese patents CN220432498U, CN 219792660 U, CN 219730666 U, CN 219526370 U, CN 117776449 A, CN117658307A, CN 117566944 A, CN 117623485 A, CN 116655098 B, CN 117623482 A, and CN111777161A. These systems achieve full utilization of ozone by setting up a multi-stage reaction system, making the oxidation reaction of wastewater more thorough, reducing the size of a single reaction device, and making the operation more flexible. The exhaust gas from the rear stage of some two-stage reaction systems can be introduced into the previous stage for reuse. However, the total reaction volume of the multi-stage reaction system is relatively large and the system is relatively complex. In addition, ozone is generally added through jet or microporous aeration devices, and the size of ozone bubbles is still relatively large, generally in the micron or millimeter level, and the utilization efficiency of ozone is still not high. CN117623485A, CN116655098B, and CN111777161A use jet micro-nano bubble generators to add ozone. Although micro-nano bubbles (size of several microns to submicrons) are smaller than micro bubbles (size of tens of microns or more), the jet micro-nano bubble generator consumes relatively large amounts of energy, and the uniformity of the ozone bubbles is relatively poor. Small bubbles easily collide and merge into large bubbles. Although CN117623482A uses a pressurized air dissolving tank, the pressurized air dissolving water is still added using a jet pipe, which still cannot avoid the problems of high energy consumption of ozone addition and uneven bubble size. Although CN 111777161 A uses an ozone pressure dissolving integrated unit, its internal structure, principle, and operating pressure are not disclosed. All wastewater enters the pressure dissolving unit, which inevitably increases the energy consumption of wastewater treatment and increases operating costs.

[0007] The method of ozone addition is a key factor in ozone catalytic oxidation wastewater treatment systems. It affects ozone bubble size, contact between ozone and the catalyst and wastewater, and the overall reaction efficiency of the system. The larger the ozone bubbles, the more uneven their distribution within the reactor, the faster their rise, and the shorter the ozone's residence time within the reactor, resulting in lower ozone utilization efficiency and the overall reaction efficiency of the system. Since the concentration of ozone produced by an ozone generator is only 0.5-6%, the resulting ozone solubility is generally only around 10%, resulting in low ozone utilization efficiency. To improve ozone utilization efficiency in ozone catalytic oxidation systems, the residence time of the catalyst filter bed in typical ozone reactors is typically over one hour. This increases the reactor volume and catalyst usage, leading to high construction costs for ozone catalytic oxidation reactors.

[0008] In summary, the currently disclosed ozone catalytic oxidation reaction systems can be divided into homogeneous reaction systems and heterogeneous reaction systems. The homogeneous reaction system can fully mix the ozone, catalyst and wastewater by setting a stirring device. The reaction time is short, and the residual ozone in the tail gas can also be partially recycled. However, the catalyst in the effluent is difficult to recycle and the catalyst must be added continuously. The method of recovering the catalyst with a ceramic filter is not yet mature in technology. The filter is easily clogged and needs to be cleaned frequently. Although the commonly used method of adding ozone through a jet can provide kinetic energy for the mixing of the reaction liquid, the energy consumption is relatively large; the bubble size can generally only reach the micron level, and the bubbles are not very uniform; the internal circulation of the rising and falling flow is set inside the reaction device or the external circulation is set with a circulating pump, which can make the mixing reaction inside the reaction device more sufficient, but the energy consumption of the reaction will inevitably increase.

[0009] The heterogeneous reaction system uses a particle catalyst, which is placed in a fixed bed, so that the catalyst does not need to be added continuously. In such a reaction system, the liquid flows slowly through the reaction bed in a laminar state, and the reaction efficiency mainly depends on the concentration of dissolved ozone in the water; if the ozone bubble particles are relatively large and unevenly distributed, the concentration of dissolved ozone will be relatively low, and a large part of the ozone will not be utilized and will be discharged from the tail gas. A multi-stage reaction system is formed, and the tail gas of the latter stage is used for recycling in the previous stage or the current stage. To a certain extent, the utilization efficiency of ozone can be improved, but the overall ozone dissolution efficiency is still limited by the large ozone bubbles. There will still be a relatively high ozone concentration in the tail gas, which needs to be eliminated by an ozone eliminator before it can be discharged into the atmosphere; at the same time, since the residence time of the heterogeneous reaction device generally requires more than 1 hour, the volume and weight of the catalyst are relatively large, and arranging it in a single layer often requires reinforcement of the filter material bracket, which increases the manufacturing cost of the equipment; the ozone is passed through a water ejector (Venturi) The addition of a micro-nano bubble generator, or as in CN117623482A, first adds the processed clear liquid through a pipeline mixer, then pumps the dissolved clear liquid into a pressurized dissolved gas tank, and then ejects it from the jet pipe to the water inlet area of ​​the reaction unit. Although micro-nano ozone bubbles can be provided, the jet pipe has a large kinetic energy and is still a jet aeration method as a whole. In order to maintain the injection kinetic energy of the jet pipe, sufficient flow and speed must be maintained. Under such conditions, the partially released small bubbles will still collide with each other and become large bubbles again, causing uneven bubble size. In addition, the addition of ozone using the jet pipe will result in insufficient dissolved gas pressure and insufficient dissolved gas during continuous operation, thereby causing problems such as low ozone utilization efficiency. Utility Model Content

[0010] In view of the shortcomings of the prior art described above, the purpose of the present invention is to provide an ozone catalytic oxidation wastewater treatment system, which utilizes ozone to generate uniform ozone bubbles of micro-nano size that enter the wastewater, fully oxidizing the organic matter in the wastewater, thereby greatly reducing the volume of the reaction device and greatly reducing or even completely eliminating the ozone concentration in the exhaust gas.

[0011] To achieve the above-mentioned purpose and other related purposes, the present invention provides an ozone catalytic oxidation wastewater treatment system, comprising a pre-reactor, a main reactor, an ozone generator, and a dissolver. The pre-reactor and the main reactor are connected in sequence along the wastewater input direction. An ozone dissolved gas release zone is provided in the main reactor. The ozone generator is connected to the dissolver for providing ozone to the dissolver. The dissolver is respectively connected to the upper part of the main reactor and the ozone dissolved gas release zone, and is used to receive the treated water in the main reactor as dissolved gas water, and input the ozone into the ozone dissolved gas release zone to form micro-nano bubbles and enter the main reactor to oxidize organic matter in the wastewater.

[0012] Preferably, the pre-reactor is provided with a first filter material support, a first filter material supporting layer, a first catalyst bed layer, and a first water outlet trough in sequence from bottom to top along the wastewater input direction, and the first filter material support is provided with a plurality of first water distribution filter heads.

[0013] More preferably, the residence time of the wastewater in the first catalyst bed is 10-20 minutes.

[0014] Preferably, the pre-reactor is externally connected to a water inlet pipe, and the water inlet pipe is sequentially provided with a water inlet pump, a water inlet valve, and a water ejector along the wastewater input direction.

[0015] More preferably, the water inlet pipe is connected to a first backwash water pipe, and the first backwash water pipe is provided on the water inlet pipe between the ejector and the pre-reactor.

[0016] Further preferably, a first backwash water valve is provided on the first backwash water pipe.

[0017] Preferably, the pre-reactor is externally connected to an ozone monitor.

[0018] Preferably, the pre-reactor is externally connected to a first tail gas discharge pipe.

[0019] More preferably, the first exhaust gas exhaust pipe is provided with a first exhaust gas exhaust valve.

[0020] Preferably, the main reactor is provided with an ozone dissolved gas release area, a second filter material support, a second filter material supporting layer, a second catalyst bed, several reaction layers, and a second water outlet trough in sequence from bottom to top along the wastewater input direction, and the reaction layer is provided with a third filter material support and a third catalyst bed in sequence from bottom to top, and the second filter material support is provided with several second water distribution filter heads.

[0021] More preferably, the ozone dissolved gas release zone includes a plurality of ozone dissolved gas releasers, and the ozone dissolved gas releasers include an energy dissipation area formed by a detachable connection between an upper plate and a lower plate, and the energy dissipation area is provided with a first energy dissipation chamber, a second energy dissipation chamber, and a third energy dissipation chamber from the inside to the outside. A dissolved air inlet pipe is provided below the first energy dissipation chamber, and the dissolved air inlet pipe is connected to the lower plate below the first energy dissipation chamber through a dissolved air water connecting port. A high-pressure air pipe is provided above the first energy dissipation chamber, and the high-pressure air pipe is connected to the upper plate above the first energy dissipation chamber through a high-pressure air connecting port. The third energy dissipation chamber is opened to release micro-nano bubbles.

[0022] Further preferably, the detachable connection between the upper plate and the lower plate is a threaded connection performed by a fastening screw.

[0023] Further preferably, a partition block is provided between the first energy dissipation chamber and the second energy dissipation chamber to form a connecting channel therebetween, and a partition plate is provided between the second energy dissipation chamber and the third energy dissipation chamber, and a release hole is provided on the partition plate.

[0024] Further preferably, the high-pressure air pipe is provided with a first air pipe section and a second air pipe section from bottom to top, the first air pipe section is connected to the upper plate above the first energy dissipation chamber through a high-pressure air connection port, and a spring pressure plate is provided in the first air pipe section.

[0025] More preferably, the residence time of the wastewater in the second catalyst bed and the third catalyst bed is 30-60 minutes.

[0026] Preferably, the main reactor and the pre-reactor are connected via a first water outlet pipe.

[0027] More preferably, the wastewater input end at the lower portion of the main reactor is connected to the first water outlet trough via a first water outlet pipe.

[0028] More preferably, an intermediate water pump and an intermediate valve are sequentially provided on the first outlet pipe along the wastewater input direction, and a second backwash water pipe is also connected to the first outlet pipe, and the second backwash water pipe is provided on the first outlet pipe between the intermediate valve and the main reactor.

[0029] Further preferably, a second backwash water valve is provided on the second backwash water pipe.

[0030] Preferably, the main reactor is externally connected to a second water outlet pipe.

[0031] More preferably, the second water outlet pipe is connected to the second water outlet trough at the upper part of the main reactor.

[0032] Preferably, the main reactor is externally connected to a second tail gas connecting pipe.

[0033] More preferably, a second tail gas connecting valve is provided on the second tail gas connecting pipe.

[0034] More preferably, one end of the second tail gas connecting pipe is connected to the top of the main reactor, and the other end of the second tail gas connecting pipe is connected to the water ejector.

[0035] Preferably, the ozone generator is connected to the aerator via an ozone input pipe.

[0036] More preferably, the ozone input pipe is provided with an ozone generator outlet valve, an air compressor, and an aerator air inlet pipe valve in sequence along the ozone input direction.

[0037] More preferably, the ozone input pipe is connected to a first tail gas connecting pipe and a compressed air pipe.

[0038] Further preferably, a first exhaust gas connecting pipe valve is provided on the first exhaust gas connecting pipe.

[0039] Further preferably, a second tail gas discharge pipe is connected to the first tail gas connecting pipe, one end of the second tail gas discharge pipe is connected to the first tail gas connecting pipe, and the other end of the second tail gas discharge pipe is connected to the main reactor.

[0040] Most preferably, a second tail gas discharge valve is provided on the second tail gas discharge pipe, one end of the second tail gas discharge pipe is connected to the first tail gas connecting pipe valve and the first tail gas connecting pipe between the pre-reactor, and the other end of the tail gas discharge pipe is connected to the top of the main reactor.

[0041] Further preferably, one end of the compressed air pipe is connected to the ozone input pipe between the air compressor and the dissolver air inlet valve, and the other end of the compressed air pipe is connected to the high-pressure air pipe above the ozone dissolved gas release area.

[0042] Further preferably, a compressed air valve is provided on the compressed air pipe.

[0043] Most preferably, the compressed air pipe is connected to a compressed air exhaust pipe, and the compressed air exhaust pipe is provided with a compressed air exhaust valve.

[0044] Further preferably, the compressed air pipe is connected to the second air pipe section of the high-pressure air pipe.

[0045] Preferably, a pressure gauge is provided on the top of the aerator.

[0046] Preferably, a dissolved air water nozzle is provided at the top of the aerator.

[0047] Preferably, the residence time of the wastewater in the aerator is 2-5 minutes.

[0048] Preferably, the aerator is connected to the main reactor via a first aeration water pipe and a second aeration water pipe respectively.

[0049] More preferably, a dissolved air water release valve is provided on the first dissolved air water pipe.

[0050] More preferably, the second dissolved air water pipe is provided with a dissolved air water pump.

[0051] More preferably, the first dissolved air water pipe is provided with a plurality of first dissolved air water branch pipes, and the first dissolved air water branch pipes are provided with a plurality of ozone dissolved air releasers.

[0052] As described above, the ozone catalytic oxidation wastewater treatment system provided by the present invention has the following beneficial effects:

[0053] (1) The utility model provides an ozone catalytic oxidation wastewater treatment system, which can provide an efficient, reliable and economical ozone catalytic oxidation treatment device for wastewater treatment. It can be applied to the treatment of various types of difficult-to-biodegrade industrial wastewater, and is particularly suitable for deep treatment of wastewater in wastewater reuse or zero-discharge wastewater treatment projects.

[0054] (2) The utility model provides an ozone catalytic oxidation wastewater treatment system. Through the arrangement of a high-pressure dissolved air tank and an ozone dissolved air releaser, the ozone mixed into the wastewater is in the form of micro-nano bubbles. The micro-nano bubbles have a larger specific surface area and a very slow rising speed in the water, which is only a few centimeters or even a few millimeters per minute. Such ozone can obtain a higher reaction efficiency in a three-phase reaction system with a catalyst and wastewater. Before the bubbles rise to the liquid surface and burst, the ozone is completely dissolved in the water and can be fully utilized. The reaction device can be reduced in size, and the amount of catalyst used can be reduced, thereby reducing the construction cost of the reaction device. At the same time, the ozone in the exhaust gas can also be greatly reduced or even eliminated.

[0055] (3) The utility model provides an ozone catalytic oxidation wastewater treatment system, which uses only a small amount of treated water for dissolved air water, thereby saving the use of fresh water and avoiding a large amount of wastewater entering the dissolved air tank to increase energy consumption. At the same time, the organic matter remaining in the treated water can be further oxidized, decomposed, and treated; a part of the exhaust gas is passed into the inlet of the air compressor to balance the pressure of the ozone generator. At the same time, the remaining ozone in the exhaust gas can be further utilized and can be used as backwash air for the main reactor when needed.

[0056] (4) The present invention provides an ozone catalytic oxidation wastewater treatment system. The provision of a pre-reaction device allows the ozone in the tail gas produced by the main reactor to be recycled, completely eliminating its harmful effects and eliminating the need for the installation and use of an ozone eliminator. An ozone online analyzer is provided on the top of the pre-reactor to ensure that the ozone concentration in the tail gas meets emission standards. The size of the pre-reactor is determined according to the ozone concentration in the tail gas of the main reactor, and the volume of its catalyst bed is only 30-50% of the volume of the catalyst bed of the main reactor, thereby reducing the cost of adding a pre-reactor.

[0057] (5) The utility model provides an ozone catalytic oxidation wastewater treatment system. The ozone mixture generated by the ozone generator is first dissolved into water through a high-pressure ozone dissolving tank, and then forms micro-nano bubbles through an ozone dissolving gas releaser. The micro-nano bubbles can exist in the water for a long time, thereby enabling the three-phase reaction system in the catalyst bed of the main reactor to obtain a larger and more uniform reaction interface, greatly promoting the catalytic reaction efficiency and ozone utilization rate. The reaction tail gas at the top of the main reactor is mixed into the water through a water ejector and enters the pre-reactor to participate in the catalytic oxidation reaction, so that the residual ozone in the tail gas of the main reactor can be recycled and completely eliminate the ozone in the exhaust gas.

[0058] (6) The utility model provides an ozone catalytic oxidation wastewater treatment system. The ozone bubbles formed by the ozone pressure dissolved gas tank and the pressure dissolved gas releaser are not only small but also uniform. The dissolved gas releaser will not be blocked, and the wastewater treatment capacity is large, which is suitable for wastewater treatment of various scales. BRIEF DESCRIPTION OF THE DRAWINGS

[0059] Figure 1 Shown is the overall structural diagram of an ozone catalytic oxidation wastewater treatment system in the present utility model.

[0060] Figure 2 Shown is a layout diagram of an ozone dissolved gas releaser in an ozone catalytic oxidation wastewater treatment system of the present utility model.

[0061] Figure 3 Shown is a structural diagram of an ozone dissolved gas releaser in an ozone catalytic oxidation wastewater treatment system of the utility model.

[0062] Reference numerals

[0063] 1 Pre-reactor

[0064] 101 First filter media holder

[0065] 102 first filter material supporting layer

[0066] 103 First catalyst bed

[0067] 104 The first water tank

[0068] 105 First water filter head

[0069] 2 Main reactor

[0070] 201 Second filter material holder

[0071] 202 Second filter material supporting layer

[0072] 203 Second catalyst bed

[0073] 204 Third filter material bracket

[0074] 205 Third catalyst bed

[0075] 206 Second water outlet

[0076] 207 Second water filter head

[0077] 208 Ozone dissolved gas release area

[0078] 3. Ozone generator

[0079] 4. Dissolver

[0080] 5. Ozone dissolved gas releaser

[0081] 501 board

[0082] 502 Lower plate

[0083] 503 First Energy Dissipation Chamber

[0084] 504 Second Energy Dissipation Chamber

[0085] 505 Third Energy Dissipation Room

[0086] 506 dissolved air water inlet pipe

[0087] 507 Dissolved air water connection port

[0088] 508 high pressure air pipe

[0089] 509 High-pressure gas connection port

[0090] 510 fastening screw

[0091] 511 separator block

[0092] 512 divider

[0093] 513 Release Hole

[0094] 514 First tracheal segment

[0095] 515 Second tracheal segment

[0096] 516 Spring Pressing Plate

[0097] 6 Water inlet pipe

[0098] 7 Water inlet pump

[0099] 8 Water inlet valve

[0100] 9 Water ejector

[0101] 10 First backwash water pipe

[0102] 11. First backwash water valve

[0103] 12 Ozone monitor

[0104] 13 First exhaust pipe

[0105] 131 First exhaust valve

[0106] 14 First water outlet pipe

[0107] 15 Intermediate water pump

[0108] 16 Intermediate valve

[0109] 17 Second backwash water pipe

[0110] 171 Second backwash water valve

[0111] 18 Second water outlet pipe

[0112] 19 Second exhaust gas connecting pipe

[0113] 20 Second exhaust gas connecting valve

[0114] 21 Ozone inlet pipe

[0115] 22 Ozone generator outlet valve

[0116] 23 Air compressor

[0117] 24 Dissolver air inlet valve

[0118] 25 First exhaust gas connecting pipe

[0119] 26 Compressed air pipe

[0120] 27 First exhaust gas connecting pipe valve

[0121] 28 Second exhaust pipe

[0122] 29 Second exhaust valve

[0123] 30 Compressed air valve

[0124] 31 Compressed air exhaust pipe

[0125] 32 Compressed air exhaust valve

[0126] 33 pressure gauge

[0127] 34 Dissolved air water nozzle

[0128] 35 First dissolved air water pipe

[0129] 36 Second dissolved air water pipe

[0130] 37 Dissolved air water release valve

[0131] 38 Dissolved air water pump

[0132] 39 First dissolved air water branch pipe DETAILED DESCRIPTION

[0133] The following describes the implementation of the present invention through specific embodiments. People familiar with this technology can easily understand other advantages and effects of the present invention from the contents disclosed in this specification.

[0134] See also Figures 1 to 3 . It should be noted that the structures, proportions, sizes, etc. illustrated in the drawings of this specification are only used to match the contents disclosed in the specification for people familiar with this technology to understand and read, and are not used to limit the limiting conditions for the implementation of this utility model. Therefore, they have no substantive technical significance. Any modification of the structure, change in the proportional relationship or adjustment of the size should still fall within the scope of the technical content disclosed by this utility model without affecting the efficacy and purpose that can be achieved by this utility model. At the same time, the terms such as "upper", "lower", "left", "right", "middle" and "one" quoted in this specification are only for the convenience of description, and are not used to limit the scope of the implementation of this utility model. Changes or adjustments in their relative relationships should also be regarded as the scope of the implementation of this utility model without substantially changing the technical content.

[0135] The utility model provides an ozone catalytic oxidation wastewater treatment system, such as Figure 1-3As shown, it includes a pre-reactor 1, a main reactor 2, an ozone generator 3, and an aerator 4. The pre-reactor 1 and the main reactor 2 are connected in sequence along the wastewater input direction. The main reactor 2 is provided with an ozone-dissolving gas release zone 208. The ozone generator 3 is connected to the aerator 4 for providing ozone to the aerator 4. The aerator 4 is respectively connected to the upper part of the main reactor 2 and the ozone-dissolving gas release zone 208, for receiving the treated water in the main reactor 2 as dissolved gas water, inputting ozone into the ozone-dissolving gas release zone 208 to form micro-nano bubbles and enter the main reactor 2 to oxidize organic matter in the wastewater. Specifically, it is used to receive the treated water in the main reactor 2 as dissolved gas water (water before dissolved gas), dissolve the ozone generated by the ozone generator 3, and input the dissolved gas water (water after dissolved gas) with dissolved ozone into the ozone-dissolving gas release zone 208 so that ozone forms micro-nano bubbles and enters the main reactor 2 to oxidize organic matter in the wastewater.

[0136] In the above system, the pre-reactor 1 is a conventional reactor tank. The pre-reactor 1 is used to eliminate the residual ozone in the tail gas of the main reactor 2 and utilize the organic matter entering the wastewater for catalytic oxidation reaction, thereby removing some of the organic matter in the wastewater and reducing the load of subsequent treatment equipment.

[0137] In the above system, if Figure 1 As shown, the pre-reactor 1 is provided with a first filter material support 101, a first filter material supporting layer 102, a first catalyst bed 103, and a first water outlet trough 104 in sequence from bottom to top along the wastewater input direction, and the first filter material support 101 is provided with a plurality of first water distribution filter heads 105.

[0138] In one embodiment, the first filter material support 101 is a conventional support for supporting filter material and catalyst.

[0139] In a specific embodiment, the first filter material supporting layer 102 is a supporting filler stacking area, which is used to fix the water distribution filter head and prevent the catalyst with smaller particles from approaching the filter head and the filter material support and being lost.

[0140] In a specific embodiment, the filler used in the first filter material supporting layer 102 is graded gravel or pebbles, etc., and the diameter of the filler is 8-32 mm.

[0141] In one specific embodiment, the first catalyst bed 103 is a catalyst stacking area.

[0142] In one embodiment, the catalyst used in the first catalyst bed 103 is a conventional catalyst, such as an unsupported catalyst. The diameter of the unsupported catalyst is 3 to 5 mm; the specific surface area is ≥ 200 m 2 / g; bulk density is 0.6-0.8t / m 3 , preferably 0.7t / m 3 ; pore volume ≥ 0.4cm 3 / g.

[0143] In one embodiment, the residence time of the wastewater in the first catalyst bed 103 is 10-20 minutes. The residence time of the wastewater in the first catalyst bed 103 can ensure that the residual ozone in the tail gas of the main reactor 2 is substantially completely eliminated.

[0144] In the above system, if Figure 1 As shown, the pre-reactor 1 is externally connected to a water inlet pipe 6 , on which a water inlet pump 7 , a water inlet valve 8 , and a water ejector 9 are sequentially provided along the wastewater input direction.

[0145] In one embodiment, Figure 1 As shown, the water inlet pipe 6 is provided at the wastewater input end at the lower portion of the pre-reactor 1. The wastewater input end is located on the side wall of the pre-reactor 1 below the first filter material support 101.

[0146] In one embodiment, Figure 1 As shown, the ejector 9 is a conventional ejector. Specifically, the ejector 9 is internally provided with a Venturi throat and a diffuser. When water flows through the Venturi throat, negative pressure is generated, sucking gas into the wastewater through the side opening. Then, when the water flows into the diffuser, turbulence is generated, and the mixed gas is released in the form of tiny bubbles, forming a two-phase fluid with high kinetic energy.

[0147] In one embodiment, Figure 1 As shown, the water inlet pipe 6 is connected to a first backwash water pipe 10, which is provided on the water inlet pipe 6 between the ejector 9 and the pre-reactor 1. The first backwash water pipe 10 is used to backwash the first catalyst bed 103 in the pre-reactor 1 when needed.

[0148] In a further embodiment, Figure 1 As shown, a first backwash water valve 11 is provided on the first backwash water pipe 10 .

[0149] In the above system, if Figure 1 As shown, the pre-reactor 1 is externally connected to an ozone monitor 12. The ozone monitor 12 is a conventional online ozone monitoring instrument used to detect the ozone concentration in the exhaust gas.

[0150] In one embodiment, Figure 1 As shown, the ozone monitor 12 is arranged on the top of the pre-reactor 1 .

[0151] In the above system, if Figure 1 As shown, the pre-reactor 1 is externally connected to a first tail gas discharge pipe 13 .

[0152] In one embodiment, Figure 1 As shown, the first exhaust gas exhaust pipe 13 is provided with a first exhaust gas exhaust valve 131 .

[0153] In one embodiment, Figure 1 As shown, the first tail gas discharge pipe 13 is provided at the top of the pre-reactor 1 .

[0154] In the above system, the main reactor 2 is a conventional reaction tank and is used to allow a large amount of organic matter in the wastewater to undergo an efficient catalytic oxidation reaction with ozone.

[0155] In the above system, if Figure 1 As shown, the main reactor 2 is provided with an ozone dissolved gas release area 208, a second filter material support 201, a second filter material supporting layer 202, a second catalyst bed 203, several reaction layers, and a second water outlet trough 206 from bottom to top along the wastewater input direction. The reaction layer is provided with a third filter material support 204 and a third catalyst bed 205 from bottom to top, and several second water distribution filter heads 207 are provided on the second filter material support 201.

[0156] In one embodiment, Figure 3 As shown, the ozone dissolved gas release area 208 includes a plurality of ozone dissolved gas releasers 5, and the ozone dissolved gas releaser 5 includes an energy dissipation area formed by a detachable connection between an upper plate 501 and a lower plate 502. The energy dissipation area is provided with a first energy dissipation chamber 503, a second energy dissipation chamber 504, and a third energy dissipation chamber 505 from the inside to the outside. A dissolved air water input pipe 506 is provided below the first energy dissipation chamber 503, and the dissolved air water input pipe 506 is connected to the lower plate 502 below the first energy dissipation chamber 503 through a dissolved air water connecting port 507. A high-pressure air pipe 508 is provided above the first energy dissipation chamber 503, and the high-pressure air pipe 508 is connected to the upper plate 501 above the first energy dissipation chamber 503 through a high-pressure air connecting port 509. The third energy dissipation chamber 505 is open to release micro-nano bubbles.

[0157] The above-mentioned ozone dissolved air release device 5 can instantaneously reduce the pressure of the pressure dissolved air water to normal pressure, and enable the excess ozone and air in the dissolved air water to be released in the form of micro-nano bubbles with uniform size. Inside the ozone dissolved air release device 5, there are 2 energy dissipation chambers, channels connecting the energy dissipation chambers, and release holes 513 for external dissolved air. After the dissolved air water passes through the release holes 513, it enters the last energy dissipation chamber (the third energy dissipation chamber 505). At this time, the pressure is dissipated, and a large number of micro-nano bubbles form a micro-nano formation area outside the ozone dissolved air release device 5. The setting of the energy dissipation chambers inside the ozone dissolved air release device 5 must be able to generate a pressure difference of at least 2 atmospheres under the selected release flow rate to ensure that a continuous dissolved air pressure of 3 atmospheres can be generated inside the high-pressure dissolved air device 4 during continuous operation. The formed micro-nano bubbles diffuse radially outward along with the water flow in the main reactor 2 and mix with the wastewater. Under the action of buoyancy, they enter the reaction zones of the second catalyst bed 203 and the third catalyst bed 205 through the second water distribution filter head 207 and the second filter media support layer 202. Micro-nano bubbles can provide a much larger specific surface area than micro-bubbles, and their existence time in water is much longer than that of micro-bubbles. This enables the ozone bubbles to be used up before reaching the top and bursting. This will greatly increase the efficiency of the ozone catalytic oxidation reaction, reduce the volume required for the reaction, and improve the utilization efficiency of ozone.

[0158] Since ozone is mixed in oxygen or air, the concentration of ozone in the mixed gas is generally only 0.5 - 20%. The specific gravity of ozone at room temperature is 2.14 kg / m 3 , which is greater than air. And the solubility of each different gas component in water is different (O2 < O3 < N2). According to the rule of first dissolving and then releasing, oxygen bubbles are formed first, followed by ozone, and finally nitrogen. The ozone dissolved air release device 5 releases the dissolved air water and spreads smoothly in all directions. Such a relatively stable water flow formed makes the bubbles of different gases formed not merge into large bubbles due to violent collisions with each other. The ozone dissolved air release area 208 selects the number of ozone dissolved air release devices 5 according to the size of the reaction device.

[0159] The above-mentioned ozone dissolved air release device 5 is provided with a high-pressure gas pipe 508, which can periodically perform backwashing on the ozone dissolved air release device 5 to ensure the long-term and efficient operation of the ozone dissolved air release device 5. The ozone dissolved air release device 5 can also be used as a backwashing air release head. When the filter bed of the main reactor 2 is backwashed, the tail gas or air of the pre-reactor 1 is injected through an air compressor to backwash the catalyst.

[0160] In a further embodiment, as Figure 3 shown, both the upper plate 501 and the lower plate 五十2 are circular plates.

[0161] In a further embodiment, as Figure 3As shown, the detachable connection between the upper plate 501 and the lower plate 502 is a threaded connection performed by a fastening screw 510 .

[0162] In a further embodiment, Figure 3 As shown, a partition block 511 is provided between the first energy dissipation chamber 503 and the second energy dissipation chamber 504 to form a connecting channel therebetween, and a partition plate 512 is provided between the second energy dissipation chamber 504 and the third energy dissipation chamber 505 , and a release hole 513 is provided on the partition plate 512 .

[0163] In a further embodiment, Figure 3 As shown, the high-pressure air pipe 508 is provided with a first air pipe section 514 and a second air pipe section 515 from bottom to top. The first air pipe section 514 is connected to the upper plate 501 above the first energy dissipation chamber 503 through a high-pressure air connection port 509. A spring pressure piece 516 is provided in the first air pipe section 514.

[0164] The spring pressing piece 516 provided in the above-mentioned high-pressure gas pipe 508 acts as a one-way valve for high-pressure gas. When necessary, high-pressure gas can be introduced, and the high-pressure gas pushes open the spring pressing piece 516 and enters the ozone dissolved gas releaser 5 to flush it. After flushing, the high-pressure gas passage is closed, the spring pressing piece 516 returns to its normal position, and the ozone dissolved gas releaser 5 returns to normal working state.

[0165] In a specific embodiment, the second filter material support 201 and the third filter material support 204 are conventionally used supports for supporting filter material and catalyst.

[0166] In a specific embodiment, the second filter material supporting layer 202 is a supporting filler stacking area for fixing the water distribution filter head to prevent the catalyst with smaller particles from approaching the filter head and the filter material support and being lost.

[0167] In a specific embodiment, the filler used in the second filter material supporting layer 202 is graded gravel or pebbles, etc., and the diameter of the filler is 8-32 mm.

[0168] In one embodiment, the second catalyst bed 203 and the third catalyst bed 205 are catalyst stacking areas. In order to reduce the load on the catalyst bed support layer, the catalyst bed can be designed as a multi-layer structure.

[0169] In one embodiment, the catalyst used in the second catalyst bed 203 and the third catalyst bed 205 is a conventional catalyst, specifically an unsupported catalyst. The diameter of the unsupported catalyst is 3 to 5 mm; the specific surface area is ≥ 200 m 2 / g; bulk density is 0.6-0.8t / m 3 , preferably 0.7t / m3 ; pore volume ≥ 0.4cm 3 / g.

[0170] In one embodiment, the number of the reaction layers is at least 2, preferably 2.

[0171] In one embodiment, the residence time of the wastewater in the second catalyst bed 203 and the third catalyst bed 205 is 30-60 minutes, preferably 40-50 minutes.

[0172] In the above system, if Figure 1 As shown, the main reactor 2 is connected to the pre-reactor 1 via a first water outlet pipe 14 .

[0173] In one embodiment, Figure 1 As shown, the wastewater input end at the lower portion of the main reactor 2 is connected to the first water outlet trough 104 via the first water outlet pipe 14. The wastewater input end at the lower portion of the main reactor 2 is located on the side wall of the main reactor 2 below the ozone dissolving gas releaser 5.

[0174] In one embodiment, Figure 1 As shown, an intermediate water pump 15 and an intermediate valve 16 are sequentially provided on the first outlet pipe 14 along the wastewater input direction. The first outlet pipe 14 is also connected to a second backwash water pipe 17, which is provided on the first outlet pipe 14 between the intermediate valve 16 and the main reactor 2. The second backwash water pipe 17 is used to backwash the second catalyst bed 203 and the third catalyst bed 205 in the main reactor 2 when needed.

[0175] In a further embodiment, Figure 1 As shown, a second backwash water valve 171 is provided on the second backwash water pipe 17 .

[0176] In the above system, if Figure 1 As shown, the main reactor 2 is externally connected to a second water outlet pipe 18 .

[0177] In one embodiment, Figure 1 As shown, the second outlet pipe 18 is connected to the second outlet trough 206 on the upper part of the main reactor 2, and is used to discharge the treated wastewater.

[0178] In the above system, if Figure 1 As shown, the main reactor 2 is externally connected to a second tail gas connecting pipe 19 .

[0179] In one embodiment, Figure 1 As shown, a second tail gas connecting valve 20 is provided on the second tail gas connecting pipe 19 .

[0180] In one embodiment, Figure 1 As shown, one end of the second tail gas connecting pipe 19 is connected to the top of the main reactor 2, and the other end of the second tail gas connecting pipe 19 is connected to the water ejector 9.

[0181] In the above system, if Figure 1 As shown, the ozone generator 3 is a conventional ozone generator. The ozone generator 3 is used to generate ozone and can adopt any high-voltage discharge ozone generator currently on the market. The concentration of the generated ozone varies depending on the oxygen source used.

[0182] In one embodiment, the ozone generator 3 uses air as the gas source. Generally, the ozone concentration can reach 1-6% (v / v), while using an oxygen-enriched gas source, the ozone concentration can reach 15-20% (v / v). The ozone generator 3 has no limitation on the ozone concentration.

[0183] In the above system, if Figure 1 As shown, the ozone generator 3 is connected to the aerator 4 via the ozone input pipe 21.

[0184] In one embodiment, Figure 1 As shown, the ozone input pipe 21 is provided with an ozone generator outlet valve 22, an air compressor 23, and an aerator air inlet pipe valve 24 in sequence along the ozone input direction.

[0185] In a further embodiment, the air compressor 23 is a conventionally used air compressor.

[0186] In one embodiment, Figure 1 As shown, the ozone input pipe 21 is connected to a first tail gas connecting pipe 25 and a compressed air pipe 26 .

[0187] In a further embodiment, Figure 1 As shown, one end of the first tail gas connecting pipe 25 is connected to the top of the pre-reactor 1 , and the other end of the first tail gas connecting pipe 25 is connected to the ozone input pipe 21 between the ozone generator outlet valve 22 and the air compressor 23 .

[0188] In a further embodiment, Figure 1 As shown, the first tail gas connecting pipe 25 is provided with a first tail gas connecting pipe valve 27. The first tail gas connecting pipe 25 is used to adjust the air intake of the aerator 4 and is used as a backwash gas source when the main reactor 2 is backwashed.

[0189] In a further embodiment, Figure 1As shown, a second tail gas discharge pipe 28 is connected to the first tail gas connecting pipe 25. One end of the second tail gas discharge pipe 28 is connected to the first tail gas connecting pipe 25, and the other end of the second tail gas discharge pipe 28 is connected to the main reactor 2. The second tail gas discharge pipe 28 is used to maintain pressure balance at the top of the main reactor 2.

[0190] In a further embodiment, Figure 1 As shown, a second tail gas discharge pipe 28 is provided with a second tail gas discharge valve 29, one end of the second tail gas discharge pipe 28 is connected to the first tail gas connecting pipe valve 27 and the first tail gas connecting pipe 25 between the pre-reactor 1, and the other end of the second tail gas discharge pipe 28 is connected to the top of the main reactor 2.

[0191] In a further embodiment, Figure 1 As shown, the compressed air pipe 26 is connected to the second air pipe section 515 of the high-pressure air pipe 508.

[0192] In a further embodiment, Figure 1 As shown, one end of the compressed air pipe 26 is connected to the ozone input pipe 21 between the air compressor 30 and the dissolver air inlet valve 24, and the other end of the compressed air pipe 26 is connected to the high-pressure air pipe 508 above the ozone dissolved gas release area 208.

[0193] In a further embodiment, Figure 1 As shown, a compressed air valve 30 is provided on the compressed air pipe 26 .

[0194] In a further embodiment, Figure 1 As shown, the compressed air pipe 26 is connected to a compressed air exhaust pipe 31 , and the compressed air exhaust pipe 31 is provided with a compressed air exhaust valve 32 .

[0195] In a further embodiment, Figure 1 As shown, the compressed air exhaust pipe 31 is connected to the compressed air valve 30 and the compressed air pipe 26 between the main reactor 2.

[0196] In the above system, the aerator 4 is a conventional air dissolving tank. The aerator 4 is used to allow ozone to be thoroughly dissolved in water under high pressure. The solubility of ozone conforms to Henry's law and increases proportionally with the increase of pressure. When the pressure is increased from 1 atmosphere to 3 atmospheres, the saturated solubility of ozone increases by about 3 times. When the pressure is returned to low pressure, the saturated solubility of ozone returns to a low value, and at this moment, abundant dissolved oxygen will be released in the form of micro-nano bubbles. The volume of the aerator 4 must ensure that the residence time of dissolved air water in the air dissolving tank is 2-5min. The dissolved air water contacts the gas in the aerator 4 in the form of a spray or in the form of a water film on the surface of the filler to be filled, ensuring that ozone and surplus air can be dissolved in water.

[0197] In the above system, if Figure 1 As shown, a pressure gauge 33 is provided on the top of the aerator 4.

[0198] In the above system, if Figure 1 As shown, a dissolved air water nozzle 34 is provided at the top of the aerator 4.

[0199] In the above system, if Figure 1 As shown, the residence time of the wastewater in the aerator 4 is 2-5 minutes.

[0200] In the above system, if Figure 1 As shown, the aerator 4 is connected to the main reactor 2 through a first air-dissolving water pipe (water after air-dissolving) 35 and a second air-dissolving water pipe (water before air-dissolving) 36 respectively.

[0201] In one embodiment, Figure 1 As shown, one end of the first dissolved air water pipe 35 is connected to the bottom of the dissolver 4, and the other end of the first dissolved air water pipe 35 is connected to the dissolved air water input pipe 506 below the ozone dissolved air release area 208.

[0202] In a further embodiment, Figure 1 As shown, a dissolved air water release valve 37 is provided on the first dissolved air water pipe 35 .

[0203] In one embodiment, Figure 1 As shown, one end of the second dissolved air water pipe 36 is connected to the dissolved air water nozzle 34 , and the other end of the second dissolved air water pipe 36 is connected to the side wall of the main reactor 2 between the second water outlet trough 206 and the third catalyst bed 205 .

[0204] In one embodiment, Figure 1 As shown, the second dissolved air water pipe 36 is provided with a dissolved air water pump 38 .

[0205] In one embodiment, Figure 2As shown, a plurality of first dissolved air water branch pipes 39 are provided on the first dissolved air water pipe 35 , and a plurality of ozone dissolved air releasers 5 are provided on the first dissolved air water branch pipes 39 .

[0206] In a further embodiment, Figure 2 As shown, several of the first dissolved air water branches 39 are parallel, and the distances between adjacent ozone dissolved air releasers 5 are equal.

[0207] The above-mentioned pumps are all centrifugal pumps, and the above-mentioned valves are all gate valves or butterfly valves.

[0208] The following combination Figure 1-3 , explaining the specific use process of an ozone catalytic oxidation wastewater treatment system in the utility model.

[0209] The operator uses Figure 1-3When an ozone catalytic oxidation wastewater treatment system is shown, the water inlet valve 8 is opened, and the wastewater is first pumped into the pre-reactor 1 by the water inlet pump 7 through the water ejector 9. A venturi throat and a diffusion tube are arranged inside the water ejector 9. When the water flows through, a negative pressure is formed inside the water ejector 9. The tail gas generated at the top of the main reactor 2 is sucked into the venturi throat through the second tail gas connecting pipe 19 by relying on this negative pressure, and the microbubbles are formed into the wastewater through the diffusion tube of the water ejector 9 and enter the pre-reactor 1 together with the wastewater. The wastewater and the microbubbles are successively passed through the second tail gas connecting pipe 19 in the pre-reactor 1. A filter material bracket 101, a first water distribution filter head 105, a first filter material supporting layer 102, and a first catalyst bed 103 enter the first water outlet trough 104; in this process, a part of the ozone remaining in the tail gas of the main reactor 2 dissolves into the water in the pre-reactor 1, and generates hydroxyl free radicals under the action of the catalyst of the first catalyst bed 103, and the remaining ozone slowly rises with the bubbles and continuously dissolves into the water, oxidizing the organic matter in the wastewater, thereby making full use of the ozone and removing some of the organic matter in the wastewater. The pre-reactor 1 enters the main reactor 2 through the first outlet pipe 14 and the intermediate water pump 15. In the main reactor 2, the wastewater passes through the ozone dissolved gas release area 208, the second filter material support 201, the second water distribution filter head 207, the second filter material support layer 202, the second catalyst bed 203, and several reaction layers, and enters the second outlet trough 206. The reaction layers are provided with the third filter material support 204 and the third catalyst bed 205 from bottom to top; and flows out of the main reactor 2 through the second outlet pipe 18 connected to the second outlet trough 206 for discharge or subsequent treatment. At the same time, the high-pressure dissolved air from the high-pressure aerator 4 is introduced into the main reactor 2 through the first dissolved air pipe 35 and the ozone dissolving gas releaser 5. The wastewater and the ozone introduced in the form of dissolved and micro-nano bubbles enter the second catalyst bed 203 and the third catalyst bed 205, where hydroxyl radicals are generated under the action of the catalyst. The remaining ozone is continuously dissolved from the bubbles as the bubbles slowly rise into the water, oxidizing the organic matter in the wastewater. This fully utilizes the ozone and removes the organic matter in the wastewater. A small amount of the ozone that enters the main reactor 2 and is not fully utilized will enter the tail gas. This part of the tail gas will be reused in the pre-reactor 1 through the second tail gas connecting pipe 19 and the water ejector 9. The ozone concentration in the tail gas of the pre-reactor 1 is detected by the ozone monitor 12 to ensure that the ozone concentration meets the emission standards. If the ozone concentration in the tail gas exceeds the dischargeable range, the tail gas is sent to the pressure aerator 4 through the first tail gas connecting pipe 13 for recycling. In order to keep the pressure of the tail gas space at the top constant, a second tail gas discharge pipe 28 is provided at the top of the main reactor 2 and is connected to the first tail gas connecting pipe 25 at the top of the pre-reactor 1 .

[0210] The ozone generated by the ozone generator 3 enters the high-pressure dissolver 4 through the ozone input pipe 21 and the air compressor 23. The air compressor 23 is connected to the first tail gas connecting pipe 25 at the top of the pre-reactor 1. A first tail gas connecting pipe valve 27 is provided in the first tail gas connecting pipe 25 so that it can be closed or the flow rate can be adjusted when necessary. In order to save the consumption of fresh water, the treated water of the main reactor 2 is used as dissolved air water, and a dissolved air pump 38 is provided to press the treated water into the dissolver 4. When the dissolved air water enters the dissolver 4, it passes through the dissolved air nozzle 34 so that the dissolved air water is in the form of dispersed droplets. The dissolver 4 is filled with filler so that the dissolved air water flows down in the dissolver 4 in the form of a water film, which facilitates the full contact of water and gas for dissolving. During operation, the pressure of the dissolver 4 is determined by the resistance of the ozone dissolved air releaser 5, and the pressure of the dissolver 4 can be adjusted by adjusting the size of the internal channel of the ozone dissolved air releaser 5. During operation, the pressure in the dissolver 4 must be maintained at 3-4 atmospheres to ensure that enough gas is dissolved in the dissolved air water. The residence time of the wastewater in the aerator 4 is 2-5 minutes to ensure that all the gas can be dissolved in the dissolved water. The aerator 4 is provided with a pressure gauge 33 for monitoring the pressure of the aerator 4 and ensuring that the pressure of the aerator 4 is within a safe range. A first dissolved air water pipe 35 is provided at the bottom of the aerator 4. The first dissolved air water pipe 35 is connected to the interface at the bottom of the ozone dissolved air releaser 5. The outlet of the air compressor 23 is provided with a compressed air pipe 26, which is connected to the upper interface of the ozone dissolved air releaser 5, for cleaning the ozone dissolved air releaser 5 when necessary or backwashing the main reactor 2 through the ozone dissolved air releaser 5.

[0211] When backwashing the second catalyst bed 203 and the third catalyst bed 205 of the main reactor 2, the ozone generator 3 is turned off, the dissolved air pump 38, the dissolved air inlet pipe valve 24 and the dissolved air release valve 37 are turned off, the compressed air valve 30 is opened, the water inlet pump 7, the intermediate water pump 15, and the intermediate valve 16 are turned off, and the second backwash water valve 171 is opened. At this time, the air compressor 23 presses the tail gas (air) at the top of the pre-reactor 1 into the main reactor 2 through the ozone dissolved air releaser 5, and backwashes the second catalyst bed 203 and the third catalyst bed 205 together with the incoming backwash water to prevent the catalyst bed from being blocked.

[0212] Example 1

[0213] A coal chemical biochemical treatment effluent, water volume 250m 3 / h, COD150mg / L, NH310mg / L, open the water inlet valve 8, and the wastewater is pumped into the pre-reactor 1 by the water inlet pump 7 through the water ejector 9. When the water flows through the water ejector 9, a negative pressure is formed inside the pre-reactor 1. Relying on this negative pressure, the tail gas generated at the top of the main reactor 2 is sucked into the water ejector 9 through the second tail gas connecting pipe 19, forming microbubbles that mix with the wastewater and enter the pre-reactor 1 together with the wastewater. The wastewater and microbubbles pass through the first filter material support 101, the first water distribution filter head 105, the first filter material supporting layer 102, and the first catalyst bed 103 in the pre-reactor 1 and enter the first water outlet trough 104. During this process, a portion of the ozone remaining in the tail gas dissolves into the water in the pre-reactor 1 and generates hydroxyl free radicals under the action of the catalyst in the first catalyst bed 103. The remaining ozone slowly rises with the bubbles and continuously dissolves into the water, oxidizing the organic matter in the wastewater. In this way, the ozone is fully utilized and some of the organic matter in the wastewater is removed. The pre-reactor 1 enters the main reactor 2 through the first outlet pipe 14 and the intermediate water pump 15. Within the main reactor 2, the wastewater passes through the ozone-dissolving gas release zone 208, the second filter material support 201, the second water distribution filter head 207, the second filter material support layer 202, the second catalyst bed 203, and several reaction layers, and then flows out of the main reactor 2 through the second outlet pipe 18 connected to the second outlet trough 206 for discharge or subsequent treatment. At the same time, the high-pressure dissolved air water from the high-pressure aerator 4 introduces ozone into the main reactor 2 through the first dissolved air pipe 35 and the ozone-dissolving gas releaser 5. The wastewater and the ozone introduced in the form of dissolved and micro-nano bubbles enter the second catalyst bed 203 and the third catalyst bed 205, where they are activated by the catalyst to generate hydroxyl radicals. The remaining ozone slowly rises with the bubbles and continuously dissolves into the water, oxidizing the organic matter in the wastewater. As a result, the ozone is fully utilized and the organic matter in the wastewater is removed. A small amount of unused ozone entering the main reactor 2 enters the tail gas, which is then recycled into the pre-reactor 1 via the second tail gas connecting pipe 19 and the water ejector 9. The ozone concentration in the tail gas of the pre-reactor 1 is detected by an ozone monitor 12 to ensure that the ozone concentration meets the emission standards. If the ozone concentration in the tail gas exceeds the dischargeable range, the tail gas is sent to the pressure dissolver 4 for recycling via the first tail gas connecting pipe 13. To maintain a constant pressure in the top tail gas space, a second tail gas discharge pipe 28 is installed at the top of the main reactor 2 and connected to the first tail gas connecting pipe 25 at the top of the pre-reactor 1.

[0214] The ozone generated by the ozone generator 3 enters the high-pressure dissolver 4 through the ozone input pipe 21 and the air compressor 23. The air compressor 23 is connected to the first tail gas connecting pipe 25 at the top of the pre-reactor 1. A first tail gas connecting pipe valve 27 is provided in the first tail gas connecting pipe 25 so that it can be closed or the flow rate can be adjusted when necessary. In order to save water, the treated water of the main reactor 2 is used as dissolved air water, and a dissolved air pump 38 is provided to press the treated water into the dissolver 4. When the dissolved air water enters the dissolver 4, it passes through the dissolved air nozzle 34 so that the dissolved air water is in the form of dispersed droplets. The dissolver 4 is filled with filler so that the dissolved air water flows down in the dissolver 4 in the form of a water film, which facilitates the full contact of water and gas for dissolving. During operation, the pressure of the dissolver 4 is determined by the resistance of the ozone dissolved air releaser 5, and the pressure of the dissolver 4 can be adjusted by adjusting the size of the internal channel of the ozone dissolved air releaser 5. During operation, the pressure in the dissolver 4 must be maintained at 3-4 atmospheres to ensure that enough gas is dissolved in the dissolved air water. The residence time of the wastewater in the aerator 4 is 3 minutes so that all the gas is dissolved in the dissolved water. The aerator 4 is provided with a pressure gauge 33 for monitoring the pressure of the aerator 4 and ensuring that the pressure of the aerator 4 is within a safe range. A first dissolved air water pipe 35 is provided at the bottom of the aerator 4. The first dissolved air water pipe 35 is connected to the interface at the bottom of the ozone dissolved air releaser 5. The outlet of the air compressor 23 is provided with a compressed air pipe 26, which is connected to the upper interface of the ozone dissolved air releaser 5 for cleaning the ozone dissolved air releaser 5 when needed.

[0215] When backwashing the second catalyst bed 203 and the third catalyst bed 205 of the main reactor 2, the ozone generator 3 is turned off, the dissolved air pump 38, the dissolved air inlet pipe valve 24 and the dissolved air release valve 37 are turned off, the compressed air valve 30 is opened, the water inlet pump 7, the intermediate water pump 15, and the intermediate valve 16 are turned off, and the second backwash water valve 171 is opened. At this time, the air compressor 23 presses the tail gas (air) at the top of the pre-reactor 1 into the main reactor 2 through the ozone dissolved air releaser 5, and backwashes the second catalyst bed 203 and the third catalyst bed 205 together with the incoming backwash water to prevent the catalyst bed from being blocked.

[0216] The water quality of the inlet water and the outlet water of the pre-reactor and the main reactor in this Example 1 is shown in Table 1.

[0217] Table 1 Main indicators of inlet and outlet water quality

[0218]

[0219] In summary, the present invention provides an ozone catalytic oxidation wastewater treatment system that utilizes a pressure dissolver and a dissolved air releaser to enable ozone to generate micro-nano-scale ozone bubbles. It has a large wastewater treatment capacity and is suitable for wastewater treatment of various sizes. The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the present invention. Anyone familiar with this technology may modify or change the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or changes made by those with ordinary knowledge in the technical field without departing from the spirit and technical ideas disclosed in the present invention should still be covered by the claims of the present invention.

Claims

1. An ozone catalytic oxidation wastewater treatment system, characterized in that: The invention comprises a pre-reactor (1), a main reactor (2), an ozone generator (3), and an aerator (4). The pre-reactor (1) and the main reactor (2) are sequentially connected along the wastewater input direction. An ozone dissolved gas release zone (208) is provided in the main reactor (2). The ozone generator (3) is connected to the aerator (4) for providing ozone to the aerator (4). The aerator (4) is respectively connected to the upper part of the main reactor (2) and the ozone dissolved gas release zone (208) for receiving the treated water in the main reactor (2) as dissolved gas water, and inputting the ozone into the ozone dissolved gas release zone (208) to form micro-nano bubbles and enter the main reactor (2) to oxidize organic matter in the wastewater.

2. The ozone catalytic oxidation wastewater treatment system according to claim 1, characterized in that: The pre-reactor (1) is provided with a first filter material support (101), a first filter material supporting layer (102), a first catalyst bed (103), and a first water outlet trough (104) in sequence from bottom to top along the wastewater input direction, and the first filter material support (101) is provided with a plurality of first water distribution filter heads (105); And / or, the pre-reactor (1) is externally connected to a water inlet pipe (6), and the water inlet pipe (6) is provided with a water inlet pump (7), a water inlet valve (8), and a water ejector (9) in sequence along the wastewater input direction; and / or, the pre-reactor (1) is externally connected to an ozone monitor (12); And / or, the pre-reactor (1) is externally connected to a first tail gas discharge pipe (13).

3. The ozone catalytic oxidation wastewater treatment system according to claim 2, characterized in that: The water inlet pipe (6) is connected to a first backwash water pipe (10), which is provided on the water inlet pipe (6) between the ejector (9) and the pre-reactor (1); a first backwash water valve (11) is provided on the first backwash water pipe (10); And / or, the first tail gas discharge pipe (13) is provided with a first tail gas discharge valve (131).

4. The ozone catalytic oxidation wastewater treatment system according to claim 2, characterized in that: The main reactor (2) is provided with an ozone dissolved gas release area (208), a second filter material support (201), a second filter material supporting layer (202), a second catalyst bed (203), a plurality of reaction layers, and a second water outlet trough (206) in sequence from bottom to top along the wastewater input direction; the reaction layer is provided with a third filter material support (204) and a third catalyst bed (205) in sequence from bottom to top; and the second filter material support (201) is provided with a plurality of second water distribution filter heads (207); and / or, the main reactor (2) is connected to the pre-reactor (1) via a first water outlet pipe (14); And / or, the main reactor (2) is externally connected to a second water outlet pipe (18); And / or, the main reactor (2) is externally connected to a second tail gas connecting pipe (19).

5. The ozone catalytic oxidation wastewater treatment system according to claim 4, characterized in that: The ozone dissolving gas release zone (208) includes a plurality of ozone dissolving gas releasers (5), and the ozone dissolving gas releasers (5) include an energy dissipation area formed by detachably connecting an upper plate (501) and a lower plate (502). The energy dissipation area is provided with a first energy dissipation chamber (503), a second energy dissipation chamber (504), and a third energy dissipation chamber (505) from the inside to the outside. A dissolved air water input pipe (506) is provided below the first energy dissipation chamber (503), and the dissolved air water input pipe (506) is communicated with the lower plate (502) below the first energy dissipation chamber (503) via a dissolved air water communication port (507). A high-pressure air pipe (508) is provided above the first energy dissipation chamber (503), and the high-pressure air pipe (508) is communicated with the upper plate (501) above the first energy dissipation chamber (503) via a high-pressure air communication port (509). The third energy dissipation chamber (505) is open to release micro-nano bubbles. and / or, an intermediate water pump (15) and an intermediate valve (16) are sequentially provided on the first water outlet pipe (14) along the wastewater input direction, and a second backwash water pipe (17) is also connected to the first water outlet pipe (14), and the second backwash water pipe (17) is provided on the first water outlet pipe (14) between the intermediate valve (16) and the main reactor (2); and / or, the second water outlet pipe (18) is in communication with the second water outlet trough (206) at the upper portion of the main reactor (2); and / or, a second tail gas connecting valve (20) is provided on the second tail gas connecting pipe (19); And / or, one end of the second tail gas connecting pipe (19) is connected to the top of the main reactor (2), and the other end of the second tail gas connecting pipe (19) is connected to the water ejector (9).

6. The ozone catalytic oxidation wastewater treatment system according to claim 5, characterized in that: The upper plate (501) and the lower plate (502) are detachably connected by a threaded connection via a fastening screw (510); And / or, a partition block (511) is provided between the first energy dissipation chamber (503) and the second energy dissipation chamber (504) to form a connecting passage therebetween, and a partition plate (512) is provided between the second energy dissipation chamber (504) and the third energy dissipation chamber (505), and a release hole (513) is provided on the partition plate (512); And / or, the high-pressure air pipe (508) is provided with a first air pipe section (514) and a second air pipe section (515) in sequence from bottom to top, the first air pipe section (514) is connected to the upper plate (501) above the first energy dissipation chamber (503) via a high-pressure air connection port (509), and a spring pressing piece (516) is provided in the first air pipe section (514).

7. The ozone catalytic oxidation wastewater treatment system according to claim 5, characterized in that: The ozone generator (3) is connected to the aerator (4) via an ozone input pipe (21); an ozone generator outlet valve (22), an air compressor (23), and an aerator inlet pipe valve (24) are sequentially provided on the ozone input pipe (21) along the ozone input direction; a first tail gas connecting pipe (25) and a compressed air pipe (26) are also connected to the ozone input pipe (21).

8. The ozone catalytic oxidation wastewater treatment system according to claim 7, characterized in that: The first tail gas connecting pipe (25) is provided with a first tail gas connecting pipe valve (27); and / or, a second tail gas discharge pipe (28) is connected to the first tail gas connecting pipe (25), one end of the second tail gas discharge pipe (28) is connected to the first tail gas connecting pipe (25), and the other end of the second tail gas discharge pipe (28) is connected to the main reactor (2); a second tail gas discharge valve (29) is provided on the second tail gas discharge pipe (28); And / or, the compressed air pipe (26) is provided with a compressed air valve (30); the compressed air pipe (26) is connected to a compressed air exhaust pipe (31), and the compressed air exhaust pipe (31) is provided with a compressed air exhaust valve (32); And / or, the compressed air pipe (26) is connected to the second air pipe section (515) of the high-pressure air pipe (508).

9. The ozone catalytic oxidation wastewater treatment system according to claim 1, characterized in that: A pressure gauge (33) is provided on the top of the aerator (4); And / or, a dissolved air water nozzle (34) is provided at the top of the aerator (4); And / or, the aerator (4) is connected to the main reactor (2) via the first aerosol water pipe (35) and the second aerosol water pipe (36) respectively.

10. The ozone catalytic oxidation wastewater treatment system according to claim 9, characterized in that: The first dissolved air water pipe (35) is provided with a dissolved air water release valve (37); and / or, the second dissolved air water pipe (36) is provided with a dissolved air water pump (38); And / or, the first dissolved air water pipe (35) is provided with a plurality of first dissolved air water branch pipes (39), and the first dissolved air water branch pipes (39) are provided with a plurality of ozone dissolved air releasers (5).

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