High-salt organic wastewater ozone catalytic oxidation system

Abstract

The present application relates to an ozone catalytic oxidation system for high-salt organic wastewater, comprising: an ozone oxidation tank, an ozone catalytic oxidation tower, and an ozone catalyst. An ozone inlet pipe is arranged on the inner bottom wall of the ozone oxidation tank, and an air distribution plate is arranged inside the ozone catalytic oxidation tower. The ozone catalytic oxidation tower is connected to the ozone oxidation tank. The ozone catalyst is a tubular structure with a hollow interior, an open bottom end, and a sealed top end. Both the ozone inlet pipe and the air distribution plate are provided with ozone catalysts, and ozone can enter the interior of the ozone catalyst from the bottom opening of the ozone catalyst. Bubble-free aeration and catalytic oxidation of ozone are achieved, greatly reducing the amount of ozone added to the ozone oxidation tank. The tubular ozone catalyst performs ozone aeration and catalytic oxidation in the ozone catalytic oxidation tower, so that the ozone bubbles formed on the surface of the ozone catalyst contact with the wastewater and the ozone catalyst to carry out a catalytic oxidation reaction, avoiding the collision and coalescence of the ozone bubbles, making the reaction more complete, and improving the efficiency of organic matter removal.

Description

Technical Field

[0001] The present application relates to the technical field of industrial wastewater treatment, and in particular to an ozone catalytic oxidation system for high-salt organic wastewater. Background Art

[0002] With the development of industry, the amount of wastewater is increasing day by day. The composition of wastewater is complex, often with high salt, high organic matter, difficult to degrade, and biological toxicity. For organic wastewater, biochemical methods and advanced oxidation methods are often used to remove it.

[0003] For high-salt, difficult-to-degrade, and high-organic wastewater, biochemical methods often show that they are not uncomfortable and microorganisms are difficult to grow, making it impossible to treat them. Therefore, for high-salt organic wastewater or wastewater with difficult-to-degrade substances, ozone catalytic oxidation methods are generally used to achieve the removal of organic matter and improve the biodegradability of wastewater. The reaction mechanism of the ozone catalytic oxidation method is mainly as follows: ozone generates hydroxyl radicals with stronger oxidizing properties through the catalyst surface, and organic matter is adsorbed on the catalyst surface at the same time, and then the organic matter is oxidized by hydroxyl radicals on the catalyst surface, degraded into small molecules or mineralized, thereby achieving the removal of pollutants. However, the catalyst is mostly a granular filler. During the aeration process, bubbles rise on the surface of the spherical catalyst, collide between the gaps and coalesce into large bubbles, reducing the effective area and duration of contact between ozone, wastewater and spherical catalysts, resulting in low ozone utilization, insufficient reaction, and poor treatment effect. Therefore, the problem of how to improve the effective utilization rate of ozone has become a problem that needs to be solved urgently by those skilled in the art. Summary of the Invention

[0004] In view of this, the present application proposes an ozone catalytic oxidation system for high-salt organic wastewater, which solves the problem of low effective utilization rate of ozone.

[0005] According to one aspect of the present application, a high-salt organic wastewater ozone catalytic oxidation system is provided, comprising: an ozone oxidation tank, an ozone catalytic oxidation tower and an ozone catalyst; an ozone inlet pipe is arranged on the inner bottom wall of the ozone oxidation tank; an air distribution disk is arranged inside the ozone catalytic oxidation tower, and the ozone catalytic oxidation tower is connected to the ozone oxidation tank; the ozone catalyst is a tubular structure with a hollow interior, an open bottom end and a sealed top end; the ozone catalyst is arranged on both the ozone inlet pipe and the air distribution disk, and ozone can enter the interior of the ozone catalyst from the bottom opening of the ozone catalyst.

[0006] In a possible implementation, the side wall thickness of the ozone catalyst is 1 to 5 times the thickness of the top side wall; the side wall thickness of the ozone catalyst is in the range of 2 mm to 20 mm.

[0007] In a possible implementation, a mounting portion is provided at the bottom end of the ozone catalyst, which is detachably mounted on the ozone inlet pipe and the gas distribution plate.

[0008] In one possible implementation, the mounting portion is a tubular structure with both ends open, connected to the interior of the ozone catalyst; an external thread is provided on the outer wall of the mounting portion; and the mounting portion and the ozone catalyst are integrally formed.

[0009] In one possible implementation, a first water inlet is provided on one side wall of the ozone oxidation tank, and a first water outlet is provided on the opposite side wall; the first water inlet is provided at the same height as the first water outlet; and the first water inlet is provided at a height that is 1-1.5 times the length of the ozone catalyst.

[0010] In a possible implementation, a plurality of ozone inlet pipes are provided; the plurality of ozone inlet pipes are arranged along the length direction of the inner bottom wall of the ozone oxidation tank; and gaps are left between adjacent ozone inlet pipes.

[0011] In a possible implementation, a plurality of ozone catalysts are provided and spaced apart along the length of the ozone inlet pipe; the ozone catalysts connected to any adjacent ozone inlet pipes are staggered.

[0012] In one possible implementation, the ozone catalytic oxidation system also includes a lifting pump; the water inlet end of the lifting pump is connected to the ozone oxidation tank, and the water outlet end is connected to the ozone catalytic oxidation tower; and a second water inlet and a second water outlet are provided on the side wall of the ozone catalytic oxidation tower, and the second water inlet and the second water outlet are provided opposite to each other; the second water inlet is provided on the top side wall of the ozone catalytic oxidation tower, and the second water outlet is provided below the gas distribution plate; an ozone air inlet is provided on the top side wall of the ozone catalytic oxidation tower, and the ozone air inlet is provided below the gas distribution plate and is connected to the gas distribution plate, and an ozone tail gas outlet is provided on the top side wall of the ozone catalytic oxidation tower.

[0013] In a possible implementation, a plurality of ozone catalysts are provided, and the plurality of ozone catalysts are arranged in an array on the gas distribution plate.

[0014] On the other hand, it includes the high-salt organic wastewater ozone catalytic oxidation system described above; ozone is filled into the ozone catalyst in the ozone oxidation tank, and ozone bubbles generated from the inside to the outside of the ozone catalyst react with the ozone catalyst and the wastewater, and the ozone charging pressure threshold is within the range of 0.001-0.9 MPa; the wastewater after one aeration is discharged into the ozone catalytic oxidation tower, and ozone is filled into the ozone catalyst in the ozone catalytic oxidation tower, and ozone bubbles generated from the inside to the outside of the ozone catalyst react with the ozone catalyst and the wastewater after one aeration, and the ozone charging pressure threshold is within the range of 0.001-0.9 MPa.

[0015] The beneficial effects of the high-salt organic wastewater ozone catalytic oxidation system of the embodiment of the present application are as follows: better effluent water quality can be obtained through two aerations. The dense tubular ozone catalyst and gas volume adjustment set in the ozone oxidation tank realize bubble-free aeration and catalytic oxidation of ozone, greatly reducing the amount of ozone added. The ozone catalytic oxidation reaction is carried out on the surface and in the micropores of the tubular ozone catalyst, reducing the contact between ozone bubbles and wastewater, while improving the effective contact between ozone, wastewater and tubular ozone catalyst, making the contact between the three more stable and efficient, effectively avoiding the accelerated decomposition of ozone by pollutants, and significantly improving the efficiency of organic matter removal. Furthermore, the ozone catalytic oxidation tower is connected to the ozone oxidation tank via a lifting pump. The tubular ozone catalyst installed inside the ozone catalytic oxidation tower performs ozone aeration and catalytic oxidation. Ozone bubbles form on the catalyst surface and simultaneously come into contact with the wastewater and ozone catalyst for catalytic oxidation reaction. This allows the ozone bubbles to undergo an ozone catalytic oxidation reaction with the ozone catalyst and wastewater as soon as they begin to form, making the contact between the three more stable and efficient. This effectively prevents ozone bubbles from colliding and agglomerating on the surface or in the gaps of the granular catalyst, thereby making the reaction more complete and improving the efficiency of organic matter removal. Therefore, the combination of bubble-free aeration in the ozone oxidation tank and the ozone catalytic oxidation tower significantly improves the removal rate of pollutants in high-salt organic wastewater and the utilization rate of ozone, reduces the amount of ozone added, and is less likely to cause large amounts of ozone tail gas to diffuse and pollute the environment.

[0016] Other features and aspects of the present application will become apparent from the following detailed description of exemplary embodiments with reference to the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate exemplary embodiments, features, and aspects of the application and, together with the description, serve to explain the principles of the application.

[0018] Figure 1 A schematic diagram showing the main structure of an ozone catalytic oxidation tower of a high-salt organic wastewater ozone catalytic oxidation system according to an embodiment of the present application is shown;

[0019] Figure 2 A schematic top view of an ozone catalytic oxidation tower of a high-salt organic wastewater ozone catalytic oxidation system according to an embodiment of the present application is shown;

[0020] Figure 3 A schematic diagram showing the main structure of an ozone oxidation tank of a high-salt organic wastewater ozone catalytic oxidation system according to an embodiment of the present application;

[0021] Figure 4 A schematic top view of an ozone oxidation tank of a high-salt organic wastewater ozone catalytic oxidation system according to an embodiment of the present application is shown;

[0022] Figure 5 A schematic diagram showing the main structure of the ozone catalyst of the high-salt organic wastewater ozone catalytic oxidation system according to an embodiment of the present application;

[0023] Figure 6 A bottom-up schematic diagram of an ozone catalyst in a high-salt organic wastewater ozone catalytic oxidation system according to an embodiment of the present application is shown. DETAILED DESCRIPTION

[0024] Various exemplary embodiments, features, and aspects of the present application will be described in detail below with reference to the accompanying drawings. The same reference numerals in the accompanying drawings represent elements with the same or similar functions. Although various aspects of the embodiments are shown in the accompanying drawings, the drawings are not necessarily drawn to scale unless otherwise indicated.

[0025] It should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like, indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention or simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0026] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature identified as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, "plurality" means two or more, unless otherwise specifically defined.

[0027] The word “exemplary” is used exclusively herein to mean “serving as an example, example, or illustration.” Any embodiment described herein as “exemplary” is not necessarily to be construed as preferred or advantageous over other embodiments.

[0028] In addition, numerous specific details are provided in the detailed description below to better illustrate the present application. Those skilled in the art will appreciate that the present application can be practiced without certain specific details. In some instances, methods, means, components, and circuits well known to those skilled in the art are not described in detail in order to highlight the main purpose of the present application.

[0029] Figure 1 A schematic diagram showing the main structure according to an embodiment of the present application is shown. Figure 1 、 Figure 3 and Figure 5 As shown, the ozone catalytic oxidation system for high-salt organic wastewater in an embodiment of the present application includes: an ozone oxidation tank 100, an ozone catalytic oxidation tower 200, and an ozone catalyst 300. An ozone inlet pipe 110 is arranged on the inner bottom wall of the ozone oxidation tank 100, and an air distribution plate 210 is arranged inside the ozone catalytic oxidation tower 200. The ozone catalytic oxidation tower 200 is connected to the ozone oxidation tank 100. The ozone catalyst 300 is an overall hollow tubular structure that is vertically inserted into the ozone inlet pipe 110 and the air distribution plate 210. The bottom end of the ozone catalyst 300 is open and connected to the ozone inlet pipe 110 and the air distribution plate 210.

[0030] In this specific embodiment, better effluent quality can be achieved through two aeration cycles. The dense tubular ozone catalyst 300 and air volume control installed in the ozone oxidation tank 100 achieve bubble-free aeration and catalytic oxidation of ozone, significantly reducing the amount of ozone added. The ozone catalytic oxidation reaction occurs on the surface of the tubular ozone catalyst 300 and within the microcavities, reducing the contact between ozone bubbles and wastewater while simultaneously enhancing the effective three-phase contact between ozone, wastewater, and the tubular ozone catalyst 300. This effectively avoids the accelerated decomposition of ozone by pollutants, significantly improving the organic matter removal efficiency. Furthermore, the ozone catalytic oxidation tower 200 is connected to the ozone oxidation tank 100 via a lift pump. The tubular ozone catalyst 300 installed within the ozone catalytic oxidation tower 200 performs ozone aeration and catalytic oxidation. Ozone bubbles form on the catalyst surface and simultaneously contact the wastewater and ozone catalyst 300 to carry out the catalytic oxidation reaction. This effectively prevents ozone bubbles from colliding and coalescing on the surface or in the gaps of the granular catalyst, thereby ensuring a more complete reaction and improving the organic matter removal efficiency. Therefore, by combining the bubble-free aeration of the ozone oxidation tank 100 and the ozone catalytic oxidation tower 200, the removal rate of pollutants in high-salt organic wastewater and the ozone utilization rate are significantly improved, the ozone dosage is reduced, and it is not easy to cause a large amount of tail gas to diffuse and pollute the environment.

[0031] In one embodiment, see Figure 5 and Figure 6The sidewall thickness of the ozone catalyst 300 is 1 to 5 times the thickness of the top sidewall, and the sidewall thickness of the ozone catalyst 300 is within the range of 2 mm to 20 mm. A hollow tubular ozone catalyst 300 is used, and the ozone injected into the ozone catalyst 300 generates uniform bubbles from the inside out on the surface of the tubular ozone catalyst 300, allowing the ozone to react more fully with the ozone catalyst 300 and the wastewater, thereby increasing the effective contact area of ​​the ozone catalyst 300. Furthermore, the micro-nano bubbles generated on the surface of the ozone catalyst 300 react rapidly with the ozone catalyst 300 and the wastewater, making the contact between the ozone catalyst 300, wastewater, and ozone more stable and efficient, thereby improving the utilization rate of ozone and the ozone catalyst 300.

[0032] Furthermore, in this embodiment, the bottom end of the ozone catalyst 300 is provided with a mounting portion 310, which can be removably mounted on the ozone inlet pipe 110 and the gas distribution plate 210. By providing the mounting portion 310 at the bottom end of the tubular ozone catalyst 300, the ozone catalyst 300 can be installed in a predetermined number and position to match the concentration and dosage of the wastewater.

[0033] Furthermore, in this specific embodiment, the mounting portion 310 is an overall tubular structure with open ends, communicating with the interior of the ozone catalyst 300. External threads are provided on the outer sidewall of the mounting portion 310, and the mounting portion 310 and the ozone catalyst 300 are integrally formed. The mounting portion 310 is also a tubular structure with open ends. One end is used for mounting and fixing, while the other end is fixed to the tubular catalyst, providing communication with the interior of the tubular ozone catalyst 300. Furthermore, external threads are provided on the outer sidewall of the tubular mounting portion 310, allowing the ozone catalyst 300 to be removably mounted and connected to the gas distribution plate 210 and the ozone inlet pipe 110. Furthermore, the integral formation of the mounting portion 310 and the ozone catalyst 300 reduces the number of manufacturing processes and production costs.

[0034] In another specific embodiment, the mounting portion 310 is a tubular structure with both ends open, communicating with the interior of the ozone catalyst 300. The circumferential cross-sectional diameter of the mounting portion 310 is smaller than that of the ozone catalyst 300, allowing the ozone catalyst 300 to be directly inserted into the gas distribution plate 210 and the ozone inlet pipe 110, making it convenient for installation and removal. Furthermore, the mounting portion 310 and the ozone catalyst 300 are integrally formed, simplifying the manufacturing process and reducing production costs.

[0035] Among them, when the catalyst is made into a tubular catalyst and a γ-Al2O3 microsphere catalyst respectively, when the embodiment and the comparative example use the same mass of catalyst and the same water quality for experiments, the specific experimental parameters are as follows Table 1:

[0036]

[0037] Table 1

[0038] Ozone catalytic oxidation experiments were conducted using a tubular ozone catalyst 300 and a γ-Al2O3 microsphere catalyst of the same mass and the same active components. It can be seen from Example 1 and Comparative Example 1 that, under the same conditions, the tubular ozone catalyst 300 generates in-situ bubbles on the surface of the ozone catalyst 300 due to its aeration, which effectively avoids bubble agglomeration and increases the three-phase contact area and time of ozone, catalyst, and pollutants in wastewater, thereby making the ozone catalytic oxidation reaction more complete and faster overall. The pollutant removal rate is significantly better than that of the γ-Al2O3 catalyst. The COD removal rate of the tubular ozone catalyst 300 is 61.6%, and the COD removal rate of the γ-Al2O3 microsphere catalyst is 49.6%.

[0039] As shown in Example 2 and Comparative Example 2, when pollutant concentration increases, i.e., COD increases, the COD removal rate of the γ-Al2O3 microsphere catalyst decreases slightly, to 45.3%. The tubular ozone catalyst 300, even with a lower ozone dosage, also exhibits a lower COD removal rate, to 58.4%. Compared with Example 1 and Comparative Example 1, the removal rates of the tubular ozone catalyst 300 and the γ-Al2O3 spherical catalyst decrease by approximately 3.2% and 4.3%, respectively, when COD increases. This demonstrates that the tubular ozone catalyst 300 exhibits a more complete reaction and a higher ozone utilization rate, maintaining a high pollutant removal rate even at a lower ozone dosage.

[0040] Example 3 and Comparative Example 3 increased the salt content of the wastewater based on the previous experiments. At higher salt contents, inorganic salts often occupy the catalyst's active centers and accelerate the decomposition of ozone in the water, resulting in a decrease in the efficiency of ozone catalytic oxidation. In Example 3, the salt content was five times that of Example 2. While the ozone dosage remained unchanged (1500 mg / L), the COD removal rate of the tubular ozone catalyst 300 decreased to 50.7%, a decrease of 7.7%. When the ozone dosage of the γ-Al2O3 catalyst was increased to 3000 mg / L under high salt conditions, the COD removal rate decreased to 36.1%, a decrease of 9.2%. This shows that the tubular ozone catalyst 300 has a strong tolerance for high-salt wastewater systems.

[0041] It should be noted that the materials and proportions of the tubular ozone catalyst 300 are the same as those used in conventional catalysts and will not be described in detail here.

[0042] In one embodiment, see Figure 3 and Figure 4A first water inlet 120 is provided on one side wall of the ozone oxidation tank 100, and a first water outlet 130 is provided on the opposite side wall. The first water inlet 120 is located at the same height as the first water outlet 130, and the height of the first water inlet is 1-1.5 times the length of the ozone catalyst. The first water inlet 120 and the first water outlet 130 are provided on two opposing sides of the ozone oxidation tank 100. Wastewater that has undergone coagulation and filtration flows into the ozone oxidation tank 100 through the first water inlet 120, and the treated wastewater enters the ozone catalytic oxidation tower 200 through the first water outlet 130.

[0043] Furthermore, in this specific embodiment, the first water inlet 120 and the first water outlet 130 are both located at a height greater than or equal to the height of the tubular ozone catalyst 300, so that the wastewater in the ozone oxidation tank 100 can cover the top of the ozone catalyst 300. This arrangement allows the ozone diffused from the ozone catalyst 300 to dissolve directly. Specifically, since ozone itself has a certain solubility and can dissolve directly in wastewater, when the first water inlet 120 and the first water outlet 130 are both located at a height higher than the top of the tubular ozone catalyst 300, the ozone diffused from the ozone catalyst 300 can dissolve in the water, preventing it from escaping while conserving ozone.

[0044] In one embodiment, multiple ozone inlet pipes 110 are provided. These pipes 110 are arranged along the length of the inner bottom wall of the ozone oxidation tank 100, with gaps between adjacent pipes 110. Multiple ozone inlet pipes 110 are installed at the inner bottom end of the ozone oxidation tank 100. Arranging these pipes along the length of the tank 100 reduces the number of ozone inlet pipes 110 and reduces the manufacturing cost of the pipes 110. Gaps are also left between adjacent ozone inlet pipes 110 to facilitate installation of the ozone catalyst 300, allowing the wastewater to fully react with the ozone catalyst 300.

[0045] Furthermore, multiple ozone catalysts 300 are provided, spaced apart along the length of the ozone inlet pipe 110. The ozone catalysts 300 connected to adjacent ozone inlet pipes 110 are staggered. The presence of multiple ozone catalysts 300 increases the purification capacity of the ozone oxidation tank 100. Furthermore, gaps are left between the ozone catalysts 300 connected to adjacent ozone inlet pipes 110.

[0046] In one embodiment, see Figure 5 and Figure 6The ozone catalytic oxidation tower 200 has a second water inlet 220 and a second water outlet 230 formed on its sidewall, facing each other. The second water inlet 220 is located on the top sidewall of the ozone catalytic oxidation tower, and the second water outlet is located below the gas distribution plate. The height of the second water inlet 220 is greater than the length of the ozone catalyst 300. The ozone catalytic oxidation tower 200 has an ozone inlet 240 on its sidewall, located below and connected to the gas distribution plate 210. An ozone tail gas outlet 250 is also formed on the top sidewall of the ozone catalytic oxidation tower 200. This ozone tail gas outlet 250, located at the top of the ozone catalytic oxidation tower 200, is used to collect incompletely reacted ozone. The ozone tail gas outlet 250 is connected to the tail gas treatment system for pyrolysis treatment. It should be noted here that the exhaust gas treatment system is an existing technical means that decomposes ozone exhaust gas through high temperature.

[0047] Furthermore, in this specific embodiment, a plurality of ozone catalysts 300 are provided, and the plurality of ozone catalysts 300 are arranged in an array on the gas distribution plate 210 , with gaps left between adjacent tubular ozone catalysts 300 to allow for sufficient reaction between wastewater, ozone, and the ozone catalysts 300 .

[0048] In one embodiment, the ozone catalytic oxidation system further includes a lift pump, the water inlet of the lift pump being connected to the ozone oxidation tank 100, and the water outlet of the lift pump being connected to the ozone catalytic oxidation tower 200. The lift pump lifts wastewater from the ozone oxidation tank 100 into the ozone catalytic oxidation tower 200 for secondary aeration, thereby achieving improved effluent quality.

[0049] Implementation Method 1

[0050] Primary Aeration: The ozone oxidation tank 100 is connected to the ozone catalytic oxidation tower 200 via a lift pump. An ozone inlet pipe 110 is located on the inner bottom sidewall of the ozone oxidation tank 100. The upper opening of the ozone inlet pipe 110 is connected to the ozone oxidation tank 100, allowing pure ozone to pre-oxidize the wastewater, removing some pollutants and enriching the wastewater with ozone. The lift pump discharges the ozone-enriched wastewater from the ozone oxidation tank 100 into the ozone catalytic oxidation tower 200. A tubular ozone catalyst 300, located within the ozone catalytic oxidation tower 200, catalytically oxidizes the wastewater, removing pollutants that are difficult or difficult to remove with conventional ozone, resulting in better effluent quality.

[0051] Implementation Method 2

[0052] Secondary aeration: The ozone oxidation tank 100 is connected to the ozone catalytic oxidation tower 200 through a lifting pump. A tubular ozone catalyst 300 is provided in both the ozone oxidation tank 100 and the ozone catalytic oxidation tower 200. The first aeration is carried out in the ozone oxidation tank 100. Since the ozone catalyst 300 reacts indiscriminately and indiscriminately to the pollutants in the wastewater, there will still be residual pollutants in the wastewater. The lifting pump lifts the wastewater with residual pollutants in the ozone oxidation tank 100 into the ozone catalytic oxidation tower 200, and a second aeration is carried out through the tubular ozone catalyst 300. Among them, the ozone tail gas in the first aeration is mostly used in the second aeration. First, the ozone tail gas in the ozone oxidation tank 100 is treated, and second, the ozone consumption is reduced.

[0053] In this specific embodiment, ozone is introduced into the ozone catalyst 300 in the ozone oxidation tank 100. Ozone bubbles generated from the inside of the ozone catalyst 300 to the outside react with the ozone catalyst 300 and the wastewater. The ozone injection pressure threshold is within the range of 0.001-0.9 MPa. The wastewater after primary aeration is discharged into the ozone catalytic oxidation tower 200. Ozone is introduced into the ozone catalyst 300 in the ozone catalytic oxidation tower 200. Ozone bubbles generated from the inside of the ozone catalyst 300 to the outside react with the ozone catalyst 300 and the wastewater after primary aeration. The ozone injection pressure threshold is within the range of 0.001-0.9 MPa. Thus, when ozone is introduced into the ozone catalyst 300, which is connected to the ozone inlet pipe 110 in the ozone oxidation tank 100 and the gas distribution plate 210 in the ozone catalytic oxidation tower 200, the ozone pressure inside the tubular ozone catalyst 300 is too high, which can easily damage the sidewalls of the tubular catalyst 300. When the ozone pressure inside the tubular ozone catalyst 300 is too low, the rate at which ozone overflows the ozone catalyst 300 is too slow, affecting the overall ozone catalytic efficiency. Therefore, the ozone introduced into the tubular ozone catalyst 300 was tested. When the ozone pressure inside the tubular ozone catalyst 300 was in the range of 0.001-0.9 MPa, the surface of the tubular ozone catalyst 300 was covered with ozone bubbles, and the ozone bubble generation rate was also faster, thereby improving the overall efficiency and speed of the ozone catalytic oxidation system.

[0054] The wastewater has a salt content of 15g / L, a COD (chemical oxygen demand) of 500mg / L, and a pH of 8. The ozone oxidation tank (100) has a hydraulic retention time of 1h, an ozone dosage of 100mg / L, and a catalyst loading rate of 25% (ratio of ozone catalyst 300 volume to container volume). The ozone catalytic oxidation tower (200) has a hydraulic retention time of 1.5h, an ozone dosage of 400mg / L, and a catalyst loading rate of 35%. The COD of the effluent from the ozone oxidation tank (100) is approximately 300mg / L, with a removal rate of approximately 40%. The COD of the effluent from the ozone catalytic oxidation tower (200) is approximately 90mg / L, with a removal rate of approximately 70%. After a period of operation and water quality testing, the wastewater COD data are shown in Table 2 below:

[0055]

[0056]

[0057] Table 2

[0058] The ozone catalytic oxidation process used in the present invention has a relatively stable COD removal effect and a high removal rate. High-salinity organic wastewater differs from conventional wastewater in that the efficiency of traditional ozone catalytic oxidation is significantly reduced, with a removal rate generally only 20-40%. Pre-oxidation or secondary catalytic oxidation processes achieve an overall removal rate of approximately 30-60%. Using the tubular catalyst provided by the present invention for two-stage treatment of high-salinity organic wastewater, a high organic matter removal rate can be maintained at a relatively low ozone dosage, with the overall process achieving an organic matter removal rate of approximately 60-80%.

[0059] The steps for using the high-salt organic wastewater ozone catalytic oxidation system of this application are as follows:

[0060] After coagulation and filtration, high-salt organic wastewater enters the ozone oxidation tank 100. An ozone inlet pipe 110 is installed at the bottom of the ozone oxidation tank 100. This pipe is connected to a vertically mounted tubular ozone catalyst 300, which is connected to the bottom aeration pipe. Ozone enters the inner cavity of each tubular ozone catalyst 300 through the ozone inlet pipe 110. Through gas volume adjustment, ozone penetrates the dense ozone catalyst 300 from the inside out, diffuses to the surface of the ozone catalyst 300, and directly dissolves in the water without forming bubbles, i.e., bubble-free aeration. The ozone used is at least one of ozone generated by an ozone generator or catalytic oxidation ozone tail gas.

[0061] The effluent from the ozone oxidation tank 100 is pumped into the ozone catalytic oxidation tower 200. The ozone catalytic oxidation tower 200 also uses a tubular ozone catalyst 300 as the catalyst filler. The ozone catalyst 300 is connected to the gas distribution plate 210 at the bottom. Ozone enters the inner cavity of the tubular ozone catalyst 300 through the gas distribution plate 210, penetrates the ozone catalyst 300, and forms micro-nano bubbles on the surface for ozone catalytic oxidation. The effluent from the ozone catalytic tower enters a subsequent advanced treatment unit for further pollutant removal or reuse.

[0062] The embodiments of the present application have been described above. The above description is illustrative and not exhaustive, and is not limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments. The terminology used herein is selected to best explain the principles of the embodiments, their practical applications, or improvements to the technology in the market, or to enable other persons skilled in the art to understand the embodiments disclosed herein.

Claims

1. A high-salt organic wastewater ozone catalytic oxidation system, characterized in that: include: Ozone oxidation pool, ozone catalytic oxidation tower and ozone catalyst; An ozone inlet pipe is arranged on the inner bottom wall of the ozone oxidation tank; The ozone catalytic oxidation tower is provided with an air distribution plate inside, and the ozone catalytic oxidation tower is connected to the ozone oxidation tank; The ozone catalyst is a hollow tubular structure with an open bottom and a sealed top. The ozone catalyst is provided on both the ozone inlet pipe and the gas distribution plate, and ozone can enter the interior of the ozone catalyst from the bottom opening of the ozone catalyst; The side wall thickness of the ozone catalyst is 1 to 5 times the thickness of the top side wall; The sidewall thickness of the ozone catalyst is in the range of 2 mm to 20 mm; A first water inlet is provided on one side wall of the ozone oxidation tank, and a first water outlet is provided on the opposite side wall; The first water inlet is opened at the same height as the first water outlet; and The opening height of the first water inlet is 1-1.5 times the length of the ozone catalyst.

2. The high-salt organic wastewater ozone catalytic oxidation system according to claim 1, characterized in that: The bottom end of the ozone catalyst is provided with a mounting portion, which is detachably mounted on the ozone inlet pipe and the gas distribution plate.

3. The high-salt organic wastewater ozone catalytic oxidation system according to claim 2, characterized in that: The mounting portion is a tubular structure with two ends open, and is connected to the interior of the ozone catalyst; An external thread is provided on the outer side wall of the mounting portion; The mounting portion and the ozone catalyst are integrally formed.

4. The high-salt organic wastewater ozone catalytic oxidation system according to claim 1, characterized in that: The ozone inlet pipe is provided with a plurality of; The plurality of ozone inlet pipes are arranged along the length direction of the inner bottom wall of the ozone oxidation tank; There is a gap between adjacent ozone inlet pipes.

5. The high-salt organic wastewater ozone catalytic oxidation system according to claim 4, characterized in that: The ozone catalysts are provided in plurality and are spaced apart along the length of the ozone inlet pipe; The ozone catalysts connected to any adjacent ozone inlet pipes are arranged in a staggered manner.

6. The high-salt organic wastewater ozone catalytic oxidation system according to claim 1, characterized in that: The ozone catalytic oxidation system also includes a lift pump; The water inlet end of the lift pump is connected to the ozone oxidation tank, and the water outlet end is connected to the ozone catalytic oxidation tower; and A second water inlet and a second water outlet are provided on the side wall of the ozone catalytic oxidation tower, and the second water inlet and the second water outlet are provided opposite to each other; The second water inlet is provided on the top side wall of the ozone catalytic oxidation tower, and the second water outlet is provided below the gas distribution plate; An ozone inlet is provided on the top side wall of the ozone catalytic oxidation tower. The ozone inlet is provided below the gas distribution plate and communicates with the gas distribution plate. An ozone tail gas outlet is provided on the top side wall of the ozone catalytic oxidation tower.

7. The high-salt organic wastewater ozone catalytic oxidation system according to claim 1, characterized in that: There are multiple ozone catalysts, and the multiple ozone catalysts are arranged in an array on the gas distribution plate.

8. A method for treating high-salt organic wastewater, characterized in that: Use the high-salt organic wastewater ozone catalytic oxidation system according to any one of claims 1 to 7; The ozone catalyst in the ozone oxidation tank is filled with ozone, and ozone bubbles generated from the inside to the outside of the ozone catalyst react with the ozone catalyst and wastewater, and the ozone filling pressure threshold is within the range of 0.001-0.9 MPa; The wastewater after the first aeration is discharged into the ozone catalytic oxidation tower, and ozone is filled into the ozone catalyst in the ozone catalytic oxidation tower. Ozone bubbles generated from the inside to the outside of the ozone catalyst react with the ozone catalyst and the wastewater after the first aeration, and the ozone filling pressure threshold is in the range of 0.001-0.9 MPa.

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