An ozone contact device and a tubular reactor thereon

Abstract

This invention relates to an ozone contact device, comprising an isobaric gas chamber for introducing ozone and a plurality of gas distribution pipes connected to the isobaric gas chamber. The gas distribution pipes extend into the radial section of a reaction tube. The liquid to be treated flows within the reaction tube. Each gas distribution pipe has gas distribution holes in the reaction tube facing away from the liquid flow direction to allow ozone flowing out of the gas distribution holes to mix with the liquid flow within the reaction tube. The gas distribution holes in the bottom space of the reaction tube are large holes with larger apertures, while the gas distribution holes above the bottom space are small holes with smaller apertures. Adjacent gas distribution pipes are spaced a certain distance apart to form flow gaps. The gas distribution holes are distributed in a fan shape around the central axis of the gas distribution pipe in several rows along the length of the gas distribution pipe. A tubular reactor incorporating this device is also described. The ozone utilization rate is high, and the inlet pump head is lower.

Description

Technical Field

[0001] This invention belongs to the field of wastewater treatment, specifically relating to an ozone contact device and a tubular reactor having the same. Background Technology

[0002] Industrial wastewater upgrading and advanced treatment projects often use effluent from biological aerobic treatment, where the BOD / COD (biochemical oxygen demand / chemical oxygen demand) ratio (B / C ratio) is already quite low, even below 0.1, classifying it as recalcitrant wastewater. Therefore, to further reduce COD, more efficient oxidation treatment technologies must be employed. Advanced oxidation technologies (AEOs) are key technologies that meet this need. They remove or degrade pollutants in water, solids, and air by generating hydroxyl radicals with strong oxidizing capabilities, breaking down large, recalcitrant organic pollutants into lower-toxicity or non-toxic smaller molecules or water. Depending on the mechanism of hydroxyl radical generation and reaction conditions, AEOs can be categorized into photochemical oxidation, electrochemical oxidation, O3 / H2O2 oxidation, Fenton oxidation, and catalytic wet oxidation, among others. Among them, compared with other advanced oxidation technologies, O3 / H2O2 advanced oxidation technology has become a hot topic in the field of industrial wastewater upgrading and deep treatment technology in recent years due to its significant advantages of no secondary pollution, mild reaction conditions and clean and readily available oxidants.

[0003] However, in practical applications, O3 / H2O2 advanced oxidation technology often encounters many problems such as large equipment scale, high operating energy consumption, and unsatisfactory treatment effect due to low O3 utilization rate, which are reflected in the project investment cost and operating cost, i.e., poor technical and economic efficiency.

[0004] The main ways ozone (O3) is introduced into wastewater are through aeration, jetting, and membrane contact. Among these, Chinese patents such as "CN104370359B", "CN105692867B", "CN213060334U", "CN107963699A", and "CN104609534B" disclose methods of introducing ozone into wastewater through aeration. Chinese patents "CN104692518A" and "CN101541407B" disclose methods of mixing water and ozone and then jetting it into the wastewater. Chinese patents "CN109231417A", "CN114835209A", and "CN111003788B" disclose methods of introducing ozone into wastewater through exchange across a membrane. Of these methods, only aeration has the disadvantages of high energy consumption and high cost. While direct aeration has advantages in both energy consumption and cost, its effectiveness is unsatisfactory. Summary of the Invention

[0005] The purpose of this invention is to provide an ozone contact device that solves the problem of providing an ozone contact solution that balances energy consumption, cost, and effectiveness.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0007] This invention provides an ozone contact device, which includes an isobaric gas chamber for introducing ozone and a plurality of gas distribution pipes connected to the isobaric gas chamber. The gas distribution pipes extend into the radial section of a reaction tube. The liquid to be treated flows inside the reaction tube. The gas distribution pipes have gas distribution holes in the reaction tubes facing away from the liquid flow direction so that the ozone flowing out of the gas distribution holes mixes into the liquid flow inside the reaction tube. The gas distribution holes in the bottom space of the reaction tube are large holes with a larger aperture, and the gas distribution holes above the bottom space are small holes with a smaller aperture. Adjacent gas distribution pipes are spaced a certain distance apart to form a flow gap. The gas distribution holes are distributed in a fan shape around the central axis of the gas distribution pipe and are distributed in several rows along the length of the gas distribution pipe.

[0008] Preferably, the diameter of the large hole is 2 mm and the diameter of the small hole is 1 mm.

[0009] Furthermore, the ratio of 1mm air holes to 2mm air holes is 9:1 to 6:4.

[0010] Preferably, the isobaric air chamber is a tubular structure with an inner diameter of 25-150 mm and a length of 700-2300 mm.

[0011] Preferably, there are 3-5 gas distribution pipes arranged side by side at equal intervals on the radial section of the reaction tube. The inner diameter of the gas distribution pipe is 5-25mm, and the end of the gas distribution pipe away from the isobaric gas chamber is fixed to the inner wall of the reaction tube.

[0012] Preferably, the number of small holes in a single row on the air distribution pipe is odd, and the small holes in a single row are arranged in a 90° fan shape with equal spacing, while the number of large holes is even, and the large holes in a single row are arranged in a 90° fan shape with equal spacing.

[0013] Preferably, the spacing between adjacent rows of air distribution holes is 8-10 mm.

[0014] Preferably, the distance between the edge row and the inner wall of the reaction tube is not less than 10 mm.

[0015] A tubular reactor is also provided, comprising a reaction tube and an ozone contact device and an H2O2 contact device arranged on the reaction tube, wherein the ozone contact devices are distributed at multiple points on the reaction tube, and the ozone contact devices are any of the ozone contact devices described above.

[0016] Preferably, the concentration of H2O2 added through the H2O2 contact device is between 0-50 mg / L, and the gas / liquid ratio (Nm³) of O3 added through the ozone contact device to the inflow wastewater is... 3 / m 3 The concentration of pollutants is between 0.01 and 0.50, the residence time of wastewater in the tubular reactor is between 10 s and 10 min, and the flow rate is between 0.3 and 3.0 m / s.

[0017] Due to the application of the above technical solution, the present invention has the following advantages compared with the prior art:

[0018] The ozone contact device of this invention employs aeration for ozone contact, but incorporates an isobaric chamber. An air distribution pipe connected to this chamber provides a nearly uniform and stable supply pressure. Extending into the radial section of the reaction tube, the air distribution pipe has a large contact area with the liquid flow within the tube. Several air distribution holes on the pipe aerate the liquid flow, with deeper holes having larger diameters and upper holes having smaller diameters. The bubbles emerging from the larger holes contain more ozone and mix thoroughly with the water during their longer ascent. Furthermore, the varying bubble sizes from the larger and smaller holes create irregular turbulence in the wastewater, ensuring thorough ozone dissolution and high ozone utilization. Attached Figure Description

[0019] The following sections will describe some specific embodiments of the invention in detail by way of example and not limitation, with reference to the accompanying drawings. The same reference numerals in the drawings denote the same or similar parts or portions. Those skilled in the art should understand that these drawings are not necessarily drawn to scale. In the drawings:

[0020] Figure 1 This is a front view of the tubular reactor of the present invention;

[0021] Figure 2 yes Figure 1 The left view;

[0022] Figure 3 yes Figure 1 Rear view;

[0023] Figure 4 yes Figure 3 AA section diagram;

[0024] Figure 5 yes Figure 4 Enlarged view of the left side of the middle section;

[0025] Figure 6 yes Figure 5 Cross-sectional view of the middle section (BB);

[0026] Figure 7 yes Figure 5 CC section view;

[0027] The reference numerals in the attached figures are explained as follows:

[0028] 1. Ozone contact device; 11. Isobaric gas chamber; 12. Gas distribution pipe; 121. Gas distribution hole; 1211. Large hole; 1212. Small hole;

[0029] 2. H2O2 contact device;

[0030] 3. Reaction tube; 31. Flow gap; 32. Inlet; 33. Outlet.

[0031] 4. Mixer. Detailed Implementation

[0032] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0033] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0034] Furthermore, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0035] like Figures 1 to 3 The tubular reactor shown is... Figure 1 It is a front view. Figure 2 It is the left view. Figure 3 This is a rear view. The tubular reactor comprises multiple reaction tubes 3 connected by flanges, with the reaction tubes 3 extending spirally from the bottom inlet 32 ​​to the top outlet 33. The wastewater to be treated enters through the inlet 32 ​​and flows out through the outlet 33. Its structure is similar to that of the previously disclosed patent "CN111099715A", and is an improvement upon it.

[0036] An H2O2 contact device 2 is installed near inlet 32 ​​to inject H2O2 into the reaction tube 3. A mixer 4 is installed in the reaction tube 3 downstream of the H2O2 contact device 2. The mixer 4 is in the form of a rotating blade or a baffle plate to interfere with the water flow in the reaction tube 3, so that H2O2 and wastewater are fully mixed.

[0037] The straight pipe behind the straight pipe where inlet 32 ​​is located, that is Figure 3 An ozone contact device 1 is installed in the bottom straight pipe to inject ozone into the reaction tube 3. Ozone contact devices 1 are also installed in the two upper straight pipes, allowing for multi-point ozone injection into the reaction tube 3.

[0038] like Figure 4 The ozone contact device 1 shown is... Figure 4 yes Figure 3 A cross-sectional view (AA) shows that the ozone contact device 1 includes an isobaric chamber 11 and gas distribution pipes 12. The isobaric chamber 11 is a tubular structure, preferably with an inner diameter of 25-150 mm and a length of 700-2300 mm. Five gas distribution pipes 12 are provided, communicating with the isobaric chamber 11. The gas distribution pipes 12 extend vertically into the radial section of the reaction tube 3, that is, they cross the flow path of the liquid within the reaction tube 3. Adjacent gas distribution pipes 12 are spaced a certain distance apart, forming a flow gap 31 through which water flows. The extension direction of the gas distribution pipes 12 is unrestricted; they can extend into the reaction tube 3 obliquely or horizontally. The gas distribution pipes 12 are evenly spaced. An inner diameter of 5-25 mm is preferred for the gas distribution pipes 12. The lower end of each gas distribution pipe 12 connects to the inner wall of the reaction tube 3. Three to five gas distribution pipes 12 are preferred.

[0039] like Figure 5 As shown Figure 4 The enlarged view of the left side shows that the portion of the gas distribution pipe 12 located inside the reaction tube 3 has several gas distribution holes 121. These holes 121 face away from the direction of the incoming liquid, meaning the gas outlet direction of the gas distribution holes 121 is consistent with the water flow direction. The gas distribution holes 121 located at the bottom of the reaction tube 3 have a larger diameter, 2mm (large holes 1211). Above the large holes 1211 are small holes 1mm in diameter 1212. Ozone is introduced into the isobaric gas chamber 11 and then released from the gas distribution holes 121. The bubbles released from the large holes 1211 contain more ozone, and the rising path of these bubbles is longer than that of the bubbles released from the small holes 1212 above them. This longer path allows more ozone to dissolve in the water. Furthermore, the mixing of large and small bubbles creates irregular interference with the water flow, further facilitating the incorporation of ozone into the water flow.

[0040] In this example, the ratio of the number of 1mm air vents 121 to the number of 2mm air vents 121 is 9:1-6:4.

[0041] The gas distribution holes 121 are arranged in multiple rows in a fan-shaped pattern around the central hole of the gas distribution tube 12. These rows are evenly spaced vertically, that is, distributed along the length of the gas distribution tube 12. The spacing between adjacent rows is preferably 8-10 mm. Furthermore, the distance between the edge rows and the inner wall of the reaction tube 3 is not less than 10 mm.

[0042] like Figure 6 As shown Figure 5 In the BB cross-sectional view, the 1mm holes 1212 on the air distribution pipe 12 are arranged in a fan-shaped pattern, with a single row distribution range of 90°, evenly spaced, and the axes of adjacent holes 1212 are at 15°. The number of holes 1212 in a single row is 7, which is an odd number. It can also be other odd numbers.

[0043] like Figure 7 As shown Figure 5 The CC cross-sectional view shows that the 2mm large holes 1211 on the air distribution pipe 12 are arranged in a fan-shaped pattern, with a single row distribution range of 90°. They are evenly spaced, and the axes of adjacent large holes 1211 are at 30°. The number of large holes 1211 in a single row is 4, which is an even number. It can also be other even numbers.

[0044] The large holes 1211 and the small holes 1212 are staggered in the vertical direction, so that the bubbles released by the two can mix in an alternating manner, thereby making the ozone and water flow mix better.

[0045] In this example, the concentration of H2O2 added through H2O2 contactor 2 is between 0-50 mg / L, and the gas / liquid ratio (Nm³) of O3 added through ozone contactor 1 to the inflow wastewater is... 3 / m 3 The concentration of pollutants is between 0.01 and 0.50, the residence time of wastewater in the tubular reactor is between 10 s and 10 min, and the flow rate is between 0.3 and 3.0 m / s.

[0046] The present invention proposes an ozone contact device and a tubular reactor thereof, which solves the problems of uneven gas dispersion and insufficient gas-liquid reaction caused by single-stage ozone addition by adding ozone in stages, thereby improving the ozone utilization rate to over 90%, with rapid reaction, high volumetric load, small footprint, flexible adjustment of process conditions according to water quality, and strong shock resistance.

[0047] Compared to the design in the previously published Chinese patent "CN111099715A", the ozone contact device eliminates the mixer in the original structure and changes the structure of the pressure injector, specifically designing an isobaric gas chamber 11 and a gas distribution pipe 12. This single component achieves gas dispersion and gas-liquid mixing effects that are superior to those achieved by the original two components. Eliminating the mixer significantly reduces the total hydraulic loss of the tubular reactor, allowing for a lower head of the selected inlet pump, thereby greatly saving equipment energy consumption and reducing operating costs.

[0048] The above embodiments are only for illustrating the technical concept and features of the present invention. Their purpose is to enable those skilled in the art to understand the content of the present invention and implement it accordingly. They should not be used to limit the scope of protection of the present invention. All equivalent changes or modifications made in accordance with the spirit and essence of the present invention should be covered within the scope of protection of the present invention.

Claims

1. An ozone contact device, characterized in that, It includes an isobaric gas chamber (11) for introducing ozone and multiple gas distribution pipes (12) connected to the isobaric gas chamber (11). The gas distribution pipes (12) extend into the radial section of the reaction tube (3). The liquid being treated flows inside the reaction tube (3). The gas distribution pipes (12) have gas distribution holes (121) in the reaction tube (3) facing away from the liquid flow direction so that the ozone flowing out of the gas distribution holes (121) mixes into the liquid flow inside the reaction tube (3). The gas distribution holes (121) in the bottom space of the reaction tube (3) are large holes (1211) with a larger aperture, and the gas distribution holes above the bottom space ( 121) is a small hole (1212) with a smaller aperture. The adjacent air distribution pipes (12) are separated by a certain distance to form a flow gap (31). The air distribution holes (121) are distributed in a fan shape around the central axis of the air distribution pipe (12) and are distributed in several rows along the length of the air distribution pipe (12). The number of small holes (1212) in a single row on the air distribution pipe (12) is odd. The small holes (1212) in a single row are arranged in a 90° fan shape with equal spacing. The number of large holes (1211) is even. The large holes (1211) in a single row are arranged in a 90° fan shape with equal spacing.

2. The ozone contact device according to claim 1, characterized in that: The diameter of the large hole (1211) is 2mm, and the diameter of the small hole (1212) is 1mm.

3. The ozone contact device according to claim 2, characterized in that: The ratio of the number of 1mm air vents (121) to the number of 2mm air vents (121) is 9:1-6:

4.

4. The ozone contact device according to claim 1, characterized in that: The isobaric air chamber (11) is a tubular structure with an inner diameter of 25-150 mm and a length of 700-2300 mm.

5. The ozone contact device according to claim 1, characterized in that: There are 3-5 gas distribution pipes (12) arranged side by side at equal intervals on the radial section of the reaction tube (3). The inner diameter of the gas distribution pipe (12) is 5-25mm, and the end of the gas distribution pipe (12) away from the isobaric gas chamber (11) is fixed to the inner wall of the reaction tube (3).

6. The ozone contact device according to claim 1, characterized in that: The spacing between adjacent rows of air distribution holes (121) is 8-10 mm.

7. The ozone contact device according to claim 1, characterized in that: The distance between the edge row and the inner wall of the reaction tube (3) shall not be less than 10 mm.

8. A tubular reactor comprising a reaction tube and an ozone contact device (1) and an H2O2 contact device (2) arranged on the reaction tube, wherein the ozone contact devices (1) are distributed at multiple points on the reaction tube (3), characterized in that, The ozone contact device (1) is an ozone contact device according to any one of claims 1 to 7.

9. The tubular reactor according to claim 8, characterized in that: The concentration of H2O2 added through the H2O2 contact device (2) is between 0-50 mg / L, and the gas / liquid ratio (Nm) of the O3 added through the ozone contact device (1) to the inflow wastewater is... 3 / m 3 The concentration of pollutants is between 0.01 and 0.50, the residence time of wastewater in the tubular reactor is between 10 s and 10 min, and the flow rate is between 0.3 and 3.0 m / s.

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