High-concentration and low-concentration organic waste gas mixing device and method

Abstract

The invention discloses a high and low concentration organic waste gas mixing device and method, the device comprises an inner cylinder structure and an outer cylinder structure, the inner cylinder is sleeved in the outer cylinder, and an annular space is formed between the inner cylinder and the outer cylinder; the high-concentration waste gas distributors are arranged in a multi-stage manner, are positioned in the inner cylinder body, are communicated with the annular space, and are used for receiving the high-concentration waste gas in the annular space and uniformly distributing the high-concentration waste gas downwards; the high-concentration waste gas distributors occupy half of the space of the cross section of the inner cylinder and are arranged at intervals in a staggered manner along the axial direction of the inner cylinder; the low-concentration waste gas distributor is arranged at a low-concentration waste gas inlet in the bottom of the inner barrel, is positioned under the first-stage high-concentration waste gas distributor and is used for uniformly and upwards distributing low-concentration waste gas; and the mixed waste gas distribution plates are arranged in a multi-stage mode and located in the inner cylinder, each mixed waste gas distribution plate occupies half of the space of the cross section of the inner cylinder and is arranged in a staggered mode at intervals in the axial direction of the inner cylinder, and the arrangement mode is opposite to that of the high-concentration waste gas distributor.

Description

Technical Field

[0001] The present invention relates to the technical field of environmental waste gas treatment, and in particular to a high- and low-concentration organic waste gas mixing device and a mixing method. Background Art

[0002] VOCs are important precursors of photochemical smog and haze, causing serious harm to the surrounding environment and human health. According to statistics, VOCs emitted from industrial sources account for more than 56% of total VOCs emissions, of which VOCs emissions caused by the petrochemical industry account for about 40%, becoming the focus of control in air pollution prevention and control. In addition to organized sources such as oxidized asphalt tail gas, reforming catalyst regeneration flue gas, and oxidized sweetening tail gas, the waste gas generated by the petrochemical industry also includes a large amount of unorganized source waste gas, which needs to be properly sealed, collected and centrally treated before it can be discharged in compliance with standards. Different types of unorganized source waste gas have different emission characteristics. For example, the VOCs concentration of waste gas in the tank area will fluctuate with the size and breathing volume of the storage tank, but even in the low emission period, the VOCs concentration is still high; the waste gas emitted during the rubber production process not only has a large VOCs emission and a low concentration, but also has a complex pollutant composition; the waste gas emitted from the oil separator, flotation tank, oil pool, scum pool, etc. in the sewage treatment plant has a small amount of waste gas but a high concentration; the waste gas emitted from the wastewater biological treatment facilities such as aeration tanks, A / O tanks, oxidation ditches, membrane bioreactors, and anaerobic tanks in the sewage treatment plant has a large amount of waste gas but a low concentration. When treating waste gas, different types of complex organic waste gases need to be mixed evenly before being sent to the subsequent waste gas treatment device.

[0003] Among the many waste gas treatment technologies, catalytic oxidation and thermal storage oxidation are the main methods for VOCs waste gas purification and treatment, which can meet the near-zero emission standards. Whether catalytic oxidation technology or thermal storage oxidation technology is used, to achieve safe, efficient and stable operation of the device, the imported VOCs waste gas must meet certain requirements, that is, the imported waste gas concentration range should meet the design requirements of the device, and the waste gas concentration distribution should be relatively uniform.

[0004] In industry, homogenization tanks are often used to evenly mix high- and low-concentration organic waste gases. All waste gases are sent to the homogenization tank at the same time. A homogenization agent layer is generally provided in the homogenization tank. Under the action of the homogenization agent, the "peak shaving" and "valley filling" of the waste gas concentration can be achieved, so as to quickly suppress the fluctuation of VOCs concentration. However, due to the large size and large floor space of the homogenization tank, and the need to regularly replace the homogenization agent in the homogenization tank, the investment and operation costs of the device are increased.

[0005] There are also some technical solutions in the prior art that do not use a homogenizer and only optimize the VOCs exhaust gas mixing effect by designing the internal components in the mixing device. For example, Chinese patent CN214261415U discloses an organic waste gas mixing device, including: a mixing chamber is provided in the shell, the first air inlet is connected to the mixing chamber, and the second air inlet is connected to the mixing chamber through a plurality of air ducts; the angle between the air inlet directions of the first air inlet and the second air inlet is 45 to 90°; a bursting disc is installed on the shell; the spoiler is installed in the mixing chamber; the exhaust port is connected to the mixing chamber. This solution can solve the problem of uneven mixing of high-concentration and low-concentration exhaust gases in ordinary mixing boxes. By setting the first air inlet and the second air inlet, high-volume and low-concentration exhaust gas and low-volume and high-concentration exhaust gas can be simultaneously delivered to the mixing chamber, and the low-volume and high-concentration exhaust gas can be divided into multiple air streams and dispersedly enter the mixing chamber through a plurality of air ducts. However, this solution is difficult to control the mixed exhaust gas concentration in the local area of ​​the high-concentration exhaust gas inlet to be lower than the lower explosion limit when the concentration of the high-concentration exhaust gas is high and the gas volume is large, which poses certain safety hazards.

[0006] Therefore, there is an urgent need for an organic waste gas mixing device and a mixing method that are suitable for situations where the organic waste gas concentrations vary greatly and the flow rates vary greatly, so that the waste gas concentration distribution after mixing is relatively uniform.

[0007] The information disclosed in this background technology section is only intended to enhance the understanding of the overall background of the invention and should not be regarded as an acknowledgment or any form of suggestion that the information constitutes the prior art already known to a person skilled in the art. Summary of the invention

[0008] The object of the present invention is to provide a high- and low-concentration organic waste gas mixing device and a mixing method, which has the characteristics of simple structure, small footprint, and relatively uniform waste gas concentration distribution after mixing, which is conducive to the safe, efficient and stable operation of subsequent organic waste gas treatment devices, and is particularly suitable for occasions where the organic waste gas concentrations differ greatly and the flow rates differ greatly.

[0009] To achieve the above-mentioned purpose, according to the first aspect of the present invention, the present invention provides a high- and low-concentration organic waste gas mixing device, comprising: an inner and outer cylinder structure, wherein the inner cylinder is sleeved inside the outer cylinder, and an annular space is formed between the inner and outer cylinders; a high-concentration waste gas distributor, which is multi-stage and located in the inner cylinder and is connected to the annular space, and is used to receive the high-concentration waste gas in the annular space and distribute the high-concentration waste gas evenly downward; each high-concentration waste gas distributor occupies half of the space of the cross-section of the inner cylinder and is arranged at intervals and staggered along the axial direction of the inner cylinder; a low-concentration waste gas distributor, which is arranged at the low-concentration waste gas inlet at the bottom of the inner cylinder and is located directly below the high-concentration waste gas distributor of the first stage, and is used to distribute the low-concentration waste gas evenly upward; a mixed waste gas distribution plate, which is multi-stage and located in the inner cylinder, each mixed waste gas distribution plate occupies half of the space of the cross-section of the inner cylinder and is arranged at intervals and staggered along the axial direction of the inner cylinder, and the arrangement is opposite to that of the high-concentration waste gas distributor.

[0010] Furthermore, in the above technical solution, the high-concentration exhaust gas distributor and the mixed exhaust gas distribution plate can divide the mixed exhaust gas flow channel into a plurality of flow channel spaces, and the plurality of flow channel spaces constitute the baffle channel of the mixed exhaust gas.

[0011] Furthermore, in the above technical solution, when the inner and outer cylinders are cylinders, the high-concentration exhaust gas distributor includes: an upper end plate, which is horizontally arranged and has a semicircular structure; a lower end plate, which is horizontally arranged and has a semicircular structure, and the first through holes are evenly arranged on the lower end plate; a side end plate, which is vertically arranged at the center of the inner cylinder and fixedly connected to the side wall of the inner cylinder; the space enclosed by the upper end plate, the lower end plate and the side end plate is connected to the annular space.

[0012] Furthermore, in the above technical solution, the mixed exhaust gas distribution plate can be a horizontally arranged semicircular plate structure, and a second through hole is provided on the semicircular plate.

[0013] Furthermore, in the above technical solution, the mixed exhaust gas distribution plate can be fixed on the side wall of the inner cylinder and the side end plate of the high-concentration exhaust gas distributor.

[0014] Furthermore, in the above technical solution, the shape of the first through hole can be circular, and the opening diameter is preferably 10 to 40 mm; the number of openings and the total area can be determined according to the volume of high-concentration exhaust gas and the number of high-concentration exhaust gas distributors, and the total opening area of ​​each lower end plate satisfies the high-concentration exhaust gas flow rate of 0.2 to 3 m / s.

[0015] Furthermore, in the above technical solution, the shape of the second through hole can also be circular, and the number and area of ​​the openings can be determined according to the volume of the mixed exhaust gas. The total opening area of ​​each mixed exhaust gas distribution plate satisfies that the mixed exhaust gas flow rate is the same as the reverse high-concentration exhaust gas flow rate.

[0016] Furthermore, in the above technical solution, the low-concentration exhaust gas distributor can be a conical cylinder structure with holes opened on the surface.

[0017] Furthermore, in the above technical solution, a mixed exhaust gas outlet may be provided at the top of the inner cylinder; and a high-concentration exhaust gas inlet may be provided at the side wall of the outer cylinder.

[0018] Furthermore, in the above technical solution, a support rod may be provided between the upper end plate and the lower end plate.

[0019] Furthermore, in the above technical solution, the distance between the inner and outer cylinder walls of the annular space may be 50 to 300 mm.

[0020] According to the second aspect of the present invention, the present invention provides a method for mixing high- and low-concentration organic waste gases, using the aforementioned device, comprising the following steps: A. introducing low-concentration waste gas from the bottom of the inner cylinder and evenly distributing it upward; introducing high-concentration waste gas from the side wall of the outer cylinder into the annular space between the inner and outer cylinders, and then evenly distributing it downward through each stage of high-concentration waste gas distributor; B. The uniformly upward low-concentration waste gas is reversely mixed with the uniformly downward high-concentration waste gas from the first-stage high-concentration waste gas distributor to complete the first-stage mixing; C. The mixed waste gas flows radially along the inner cylinder toward the first-stage mixed waste gas distribution plate, and then along the axis of the inner cylinder. The mixed exhaust gas flows in the radial direction of the inner cylinder toward the second-stage mixed exhaust gas distribution plate, and then rises in the axial direction of the inner cylinder through the second-stage mixed exhaust gas distribution plate to complete the second-stage second mixing; and so on, the mixed exhaust gas is mixed with the high-concentration exhaust gas injected in reverse from each stage in turn, and passes through the mixed exhaust gas distribution plates of each stage in turn to form a return operation, and is finally discharged from the mixed exhaust gas outlet.

[0021] Furthermore, in the above technical solution, the upward low-concentration exhaust gas in step A may have the same flow rate as the downward first-stage high-concentration exhaust gas.

[0022] Furthermore, in the above technical solution, the flow rate of the mixed exhaust gas at each stage going upward can be the same as the flow rate of the high-concentration exhaust gas at the next stage going downward.

[0023] Furthermore, in the above technical solution, in the initial stage of mixing, the distribution time of each stage of high-concentration exhaust gas distributors can be delayed step by step according to the flow rate of the low-concentration exhaust gas and the size of the inner cylinder.

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] 1) The high-concentration exhaust gas of the present invention can be dispersed and injected into the low-concentration exhaust gas step by step through a multi-stage high-concentration exhaust gas distributor, rather than adding the low-concentration exhaust gas all at once, which can effectively avoid excessive concentration of mixed exhaust gas in a local area and ensure that the concentration of mixed exhaust gas in the entire area is lower than the lower explosion limit, which is safer and more reliable;

[0026] 2) The high-concentration exhaust gas of the present invention can be respectively injected into the mixed exhaust gas in reverse direction through a multi-stage high-concentration exhaust gas distributor, and the high-concentration exhaust gas flowing out of each stage of the high-concentration exhaust gas distributor is equivalent to the low-concentration exhaust gas (or mixed exhaust gas) in speed. When the reverse convection impacts, the relative speed of the two can reach the maximum value, which can effectively enhance the turbulence degree of the impact area and improve the mass transfer efficiency between the high-concentration and low-concentration exhaust gases;

[0027] 3) The high-concentration exhaust gas distributor and the mixed exhaust gas distribution plate of the present invention divide the mixed exhaust gas flow channel into a plurality of flow channel spaces, and the plurality of flow channel spaces can constitute a baffle channel for the mixed exhaust gas, thereby increasing the flow length of the mixed exhaust gas in a limited space, prolonging the mixing time, and enhancing the mass transfer effect;

[0028] 4) The mixing device of the present invention has a simple structure, small volume and floor space, and does not require a homogenizing agent, thereby saving investment and operating costs;

[0029] 5) By using the mixing device and method of the present invention, the concentration of the mixed waste gas is evenly distributed, which is conducive to the efficient and stable operation of the subsequent organic waste gas treatment device, and is particularly suitable for occasions where the organic waste gas concentration and flow rate are greatly different;

[0030] 6) The mixing method of the present invention can control the delayed distribution time of each level of high-concentration exhaust gas distributor at the inlet of each level of high-concentration exhaust gas distributor by considering factors such as gas flow rate and return distance, so as to avoid the situation in which a part of high-concentration exhaust gas flows out of the mixed exhaust gas outlet without being mixed with low-concentration exhaust gas in the initial stage of mixing.

[0031] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention and implement it according to the contents of the specification, and to make the above and other purposes, technical features and advantages of the present invention easier to understand, one or more preferred embodiments are listed below and described in detail with the accompanying drawings as follows. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 It is a schematic internal cross-sectional view of a high- and low-concentration organic waste gas mixing device of the present invention (the direction of the arrow in the figure is the direction of waste gas flow).

[0033] Figure 2 yes Figure 1 AA section view.

[0034] Description of main reference numerals:

[0035] 1-outer cylinder, 11-annular space, 2-inner cylinder, 3-lower head, 4-upper head, 5-low-concentration exhaust gas inlet, 6-high-concentration exhaust gas inlet, 7-mixed exhaust gas outlet, 8-high-concentration exhaust gas distributor, 81-upper end plate, 82-lower end plate, 821-first through hole, 83-side end plate, 84-support rod, 9-mixed exhaust gas distribution plate, 91-second through hole, 10-low-concentration exhaust gas distributor. DETAILED DESCRIPTION

[0036] The specific implementation modes of the present invention are described in detail below in conjunction with the accompanying drawings, but it should be understood that the protection scope of the present invention is not limited by the specific implementation modes.

[0037] Unless explicitly stated otherwise, throughout the specification and claims, the term “comprise” or variations such as “include” or “comprising”, etc., will be understood to include the stated elements or components but not to exclude other elements or components.

[0038] In this document, for the convenience of description, spatial relative terms such as "below", "below", "down", "above", "above", "upper", etc. may be used to describe the relationship between one element or feature and another element or feature in the accompanying drawings. It should be understood that the spatial relative terms are intended to include different orientations of the object in use or operation in addition to the orientation depicted in the figure. For example, if the object in the figure is turned over, the element described as being "below" or "below" other elements or features will be oriented "above" the element or feature. Therefore, the exemplary term "below" can include both below and above. Objects may also have other orientations (rotated 90 degrees or other orientations) and the spatial relative terms used in this document should be interpreted accordingly.

[0039] In this document, the terms "first", "second", etc. are used to distinguish two different elements or parts, and are not used to limit a specific position or relative relationship. In other words, in some embodiments, the terms "first", "second", etc. can also be interchangeable.

[0040] Example 1

[0041] like Figure 1 , 2As shown, this embodiment provides a high-low concentration organic waste gas mixing device, including: an inner and outer cylinder structure, the inner cylinder 2 is sleeved inside the outer cylinder 1, and an annular space 11 is formed between the inner and outer cylinders. Specifically, an upper head 4 can be provided at the upper end of the inner and outer cylinders, and a lower head 3 is provided at the lower end. A low-concentration waste gas inlet 5 is provided on the lower head 3, a high-concentration waste gas inlet 6 is provided on the side wall of the outer cylinder 1, and a mixed waste gas outlet 7 is provided on the upper head 4. The high-concentration waste gas distributor 8 is multi-stage and is located in the inner cylinder 2 and is connected to the annular space 11, and is used to receive the high-concentration waste gas in the annular space 11 and evenly distribute the high-concentration waste gas downward. Each high-concentration waste gas distributor 8 occupies half of the space of the cross section of the inner cylinder and is arranged in an axially spaced staggered arrangement along the inner cylinder 2. The low-concentration waste gas distributor 10 is provided at the low-concentration waste gas inlet 5 at the bottom of the inner cylinder 2, and is located directly below the first-stage high-concentration waste gas distributor, and is used to evenly distribute the low-concentration waste gas upward. Corresponding to the high-concentration exhaust gas distributor 8, the mixed exhaust gas distribution plate 9 is also arranged in multiple stages and is located in the inner cylinder 2. Specifically, each mixed exhaust gas distribution plate 9 occupies half of the space of the cross-section of the inner cylinder 2 and is arranged in an axially spaced and staggered manner along the inner cylinder 2. The arrangement is opposite to that of the high-concentration exhaust gas distributor 8.

[0042] Further Figure 1 As shown, the high-concentration exhaust gas distributor 8 and the mixed exhaust gas distribution plate 9 of this embodiment are arranged in a one-to-one correspondence, and are fixedly connected to each other and to the inner wall of the inner cylinder 2; the number of high-concentration exhaust gas distributors 8 and mixed exhaust gas distribution plates 9 is the same, both of which are two or more; each level of high-concentration exhaust gas distributors 8 and mixed exhaust gas distribution plates 9 are arranged from bottom to top along the inner cylinder 2 at a certain interval, and the interval is preferably 0.3 to 1 times the radius of the inner cylinder 2; the positions of the two adjacent levels of high-concentration exhaust gas distributors 8 and mixed exhaust gas distribution plates 9 are opposite. Through such an arrangement, the high-concentration exhaust gas distributor 8 and the mixed exhaust gas distribution plate 9 divide the mixed exhaust gas flow channel (that is, the space enclosed by the outer cylinder 1, the inner cylinder 2 and the upper and lower heads) into multiple flow channel spaces, and the multiple flow channel spaces can constitute a deflection channel for the mixed exhaust gas (refer to Figure 1 The plurality of flow channel spaces are connected by openings on the mixed exhaust gas distribution plate 9.

[0043] In the mixing device of the present embodiment, high-concentration exhaust gas is injected into low-concentration exhaust gas in a dispersed manner step by step through a multi-stage high-concentration exhaust gas distributor, rather than injecting low-concentration exhaust gas all at once as in the prior art, thereby avoiding excessive concentration of mixed exhaust gas in local areas, ensuring that the concentration of mixed exhaust gas in the entire area is lower than the lower explosion limit, and being safer and more reliable; in addition, high-concentration exhaust gas is reversely injected into the mixed exhaust gas through a multi-stage high-concentration exhaust gas distributor, which can effectively enhance the turbulence level in the impact area and improve the mass transfer efficiency between high- and low-concentration exhaust gases; furthermore, the high-concentration exhaust gas distributor and the mixed exhaust gas distribution plate divide the mixed exhaust gas flow channel into several connected areas, which can increase the flow length of the mixed exhaust gas in a limited space, extend the mixing time, and further improve the mass transfer efficiency.

[0044] Further Figure 1 , 2 As shown, when the cross-sections of the inner and outer cylinders can be circular or square, the cross-sections of the outer cylinder and the inner cylinder have the same shape, and the distance between the inner and outer cylinder walls of the annular space is preferably 50 to 300 mm. When the inner and outer cylinders are cylinders as shown in the figure, the high-concentration exhaust gas distributor may include an upper end plate 81, a lower end plate 82 and a side end plate 83. Among them, the upper end plate 81 is horizontally arranged and has a semicircular structure; the lower end plate 82 is also horizontally arranged and has a semicircular structure, which is arranged below the upper end plate 81, and the lower end plate 82 is evenly provided with first through holes 821 (reference Figure 2 ); the side end plate 83 is vertically arranged at the center of the inner cylinder 2 and extends horizontally to the side wall of the inner cylinder 2, and is fixedly connected to the side wall; the space enclosed by the upper end plate 81, the lower end plate 82 and the side end plate 83 is connected to the annular space 11. A support rod 84 can be arranged between the upper end plate 81 and the lower end plate 82. The first through hole 821 is evenly distributed on the lower end plate, and the shape of the opening can be circular, square or diamond, etc., preferably circular; the opening diameter is preferably 10 to 40 mm, and the number of openings and the total area are determined according to the gas volume of the high-concentration exhaust gas and the number of high-concentration exhaust gas distributors 8. The total opening area of ​​the lower end plate of each high-concentration exhaust gas distributor 8 should meet the high-concentration exhaust gas flow rate of 0.2 to 3 m / s, preferably 0.5 to 1.5 m / s. It should be noted here that the specific number of high-concentration exhaust gas distributors 8 in this embodiment can be determined according to the concentration difference of the inlet organic exhaust gas (i.e., the high and low concentration difference), and more high-concentration exhaust gas distributors 8 can be set when the concentration difference is large. The opening conditions of the high-concentration exhaust gas distributors 8 at each stage may be the same, or the total opening area of ​​the lower end plate of the high-concentration exhaust gas distributor 8 may be gradually reduced from bottom to top.

[0045] Further Figure 1 As shown, the mixed exhaust gas distribution plate 9 is a horizontally arranged semicircular plate structure, and a second through hole 91 is opened on the semicircular plate (refer to Figure 2). The mixed exhaust gas distribution plate 9 can be fixed on the side wall of the inner cylinder and the side end plate 83 of the high-concentration exhaust gas distributor 8. The shape of the second through hole 91 can be circular, square or diamond, etc., preferably circular; the number and area of ​​the openings are determined according to the gas volume of the mixed exhaust gas, and the total opening area of ​​each mixed exhaust gas distribution plate satisfies that the mixed exhaust gas flow rate is the same as the reverse high-concentration exhaust gas flow rate, that is, the mixed concentration exhaust gas flow rate is 0.2~3m / s, preferably 0.5~1.5m / s. The number of mixed exhaust gas distribution plates 9 in this embodiment is the same as the number of high-concentration exhaust gas distributors 8, the total opening area of ​​the mixed exhaust gas distribution plates 9 at each level is the same, and the opening diameter, number and arrangement method can be the same or different.

[0046] Further Figure 1 As shown, the low-concentration exhaust gas distributor 10 can be set as a conical cylinder structure with holes on the surface, which can evenly distribute the low-concentration exhaust gas from the bottom of the inner cylinder upward. The material of the low-concentration exhaust gas distributor 10, the inner cylinder 2, the outer cylinder 1, the upper head 4, the lower head 3, the high-concentration exhaust gas distributor 8, and the mixed exhaust gas distribution plate 9 is preferably carbon steel or stainless steel.

[0047] The mixing device of this embodiment has a simple structure, occupies a small area, and does not require a homogenizing agent, thereby saving investment and operating costs.

[0048] Example 2

[0049] This embodiment provides a method for mixing high- and low-concentration organic waste gas. The above-mentioned mixing device is used. A small flow of high-concentration waste gas enters the space surrounded by the outer cylinder 1, the inner cylinder 2 and the upper and lower heads (i.e., the annular space 11) from the high-concentration waste gas inlet 6, and then flows out through the high-concentration waste gas distributor 8; a large flow of low-concentration waste gas enters the inner cylinder 2 from the low-concentration waste gas inlet 5, and then flows out through the low-concentration waste gas distributor 10. The subsequent high- and low-concentration mixing process includes the following steps:

[0050] Step S101, low-concentration exhaust gas is introduced from the bottom of the inner cylinder 2 and evenly distributed upward; high-concentration exhaust gas is introduced from the side wall of the outer cylinder into the annular space between the inner and outer cylinders, and then evenly distributed downward through each stage of high-concentration exhaust gas distributor. Preferably, but not restrictively, the upward low-concentration exhaust gas has the same flow rate as the first stage of downward high-concentration exhaust gas, and the first stage of high-concentration exhaust gas has a similar velocity to the low-concentration exhaust gas. When the reverse convection impacts, the relative velocity of the two reaches the maximum value, which can further enhance the turbulence degree of the impact area and improve the mass transfer efficiency between high-concentration and low-concentration exhaust gases;

[0051] Step S102, the low-concentration exhaust gas flowing evenly upward is counter-mixed with the high-concentration exhaust gas flowing evenly downward from the first-stage high-concentration exhaust gas distributor, completing the first-stage first mixing;

[0052] Step S103, the mixed exhaust gas flows radially along the inner cylinder 2 toward the first-stage mixed exhaust gas distribution plate, and then rises along the axial direction of the inner cylinder to pass through the first-stage mixed exhaust gas distribution plate, that is, the gas is redistributed when flowing through the first-stage mixed exhaust gas distribution plate 9, completing the first-stage second mixing;

[0053] Step S104, the rising mixed exhaust gas is further reversely mixed with the uniformly downward high-concentration exhaust gas from the second-stage high-concentration exhaust gas distributor to complete the first mixing of the second stage;

[0054] Step S105, the mixed exhaust gas flows radially along the inner cylinder 2 toward the second-stage mixed exhaust gas distribution plate, and then rises along the axial direction of the inner cylinder 2 through the second-stage mixed exhaust gas distribution plate to complete the second mixing of the second stage; by analogy, the mixed exhaust gas is sequentially mixed with the high-concentration exhaust gas injected from each stage in reverse, and sequentially passes through the mixed exhaust gas distribution plates of each stage to form a return operation, and finally discharged from the mixed exhaust gas outlet. In this process, the speed of the mixed exhaust gas at each stage is equivalent to that of the high-concentration exhaust gas of the next stage, and the relative speed of the two reaches the maximum value when the reverse convection impacts, which can further enhance the turbulence degree in the impact area and improve the mass transfer efficiency between high- and low-concentration exhaust gases. Through the return operation of the mixed exhaust gas from bottom to top, the circulation length of the mixed exhaust gas is increased in a limited space, the mixing time is extended, and the mass transfer effect is enhanced.

[0055] Further, preferably but not restrictively, in the initial stage of mixing, the distribution time of each stage of high-concentration exhaust gas distributor can be delayed step by step according to the flow rate of the low-concentration exhaust gas and the size of the inner cylinder 2. Specifically, if the high-concentration exhaust gas distributor 8 at each downstream stage is ventilated simultaneously with the low-concentration exhaust gas distributor 10 too early, a part of the high-concentration exhaust gas will flow out of the mixed exhaust gas outlet 7 without mixing with the low-concentration exhaust gas. Taking this into account, this embodiment can set explosion-proof solenoid valves and other facilities at the entrance of each stage of high-concentration exhaust gas distributor 8 by considering factors such as gas flow rate and return distance (that is, the size of the inner cylinder), so as to control the delayed distribution time of each stage of high-concentration exhaust gas distributor.

[0056] This embodiment uses the mixing device of Example 1 to mix high-concentration organic waste gas with low-concentration organic waste gas to achieve the same technical effect as Example 1. The concentration of the mixed waste gas is evenly distributed, which is conducive to the efficient and stable operation of the subsequent organic waste gas treatment device, and is particularly suitable for occasions where the organic waste gas concentration and flow rate are greatly different.

[0057] The foregoing description of specific exemplary embodiments of the present invention is for the purpose of illustration and demonstration. These descriptions are not intended to limit the present invention to the precise form disclosed, and it is clear that many changes and variations can be made based on the above teachings. The purpose of selecting and describing the exemplary embodiments is to explain the specific principles of the present invention and its practical application, so that those skilled in the art can realize and utilize various different exemplary embodiments of the present invention and various different selections and changes. Any simple modifications, equivalent changes and modifications made to the above exemplary embodiments should fall within the scope of protection of the present invention.

Claims

1. A high- and low-concentration organic waste gas mixing device, characterized in that: include: The inner and outer cylinder structures, wherein the inner cylinder is sleeved inside the outer cylinder, and an annular space is formed between the inner and outer cylinders; A high-concentration exhaust gas distributor, which is arranged in multiple stages and is located in the inner cylinder and communicated with the annular space, is used to receive the high-concentration exhaust gas in the annular space and evenly distribute the high-concentration exhaust gas downward; each high-concentration exhaust gas distributor occupies half of the space of the cross section of the inner cylinder and is arranged in an axially spaced and staggered manner along the inner cylinder; A low-concentration exhaust gas distributor is provided at the low-concentration exhaust gas inlet at the bottom of the inner cylinder and is located directly below the first-stage high-concentration exhaust gas distributor, and is used to evenly distribute the low-concentration exhaust gas upwards; The mixed exhaust gas distribution plates are arranged in multiple stages and are located in the inner cylinder. Each mixed exhaust gas distribution plate occupies half of the space of the cross section of the inner cylinder and is arranged in an axially spaced and staggered manner along the inner cylinder. The arrangement is opposite to that of the high-concentration exhaust gas distributor.

2. The high- and low-concentration organic waste gas mixing device according to claim 1, characterized in that: The high-concentration exhaust gas distributor and the mixed exhaust gas distribution plate divide the mixed exhaust gas flow channel into a plurality of flow channel spaces, and the plurality of flow channel spaces constitute a baffle channel for the mixed exhaust gas.

3. The high- and low-concentration organic waste gas mixing device according to claim 1, characterized in that: When the inner and outer cylinders are cylinders, the high-concentration exhaust gas distributor comprises: an upper end plate, which is horizontally disposed and has a semicircular structure; A lower end plate is horizontally arranged and has a semicircular structure, and first through holes are evenly arranged on the lower end plate; The side end plate is vertically arranged at the center of the inner cylinder and fixedly connected to the side wall of the inner cylinder; the space enclosed by the upper end plate, the lower end plate and the side end plate is connected to the annular space.

4. The high- and low-concentration organic waste gas mixing device according to claim 3 is characterized in that: The mixed exhaust gas distribution plate is a horizontally arranged semicircular plate structure, and a second through hole is provided on the semicircular plate.

5. The high- and low-concentration organic waste gas mixing device according to claim 4, characterized in that: The mixed exhaust gas distribution plate is fixed on the side wall of the inner cylinder and the side end plate of the high-concentration exhaust gas distributor.

6. The high- and low-concentration organic waste gas mixing device according to claim 5, characterized in that: The first through hole is circular in shape, and the opening diameter is 10 to 40 mm; The number of openings and the total area are determined according to the volume of high-concentration exhaust gas and the number of high-concentration exhaust gas distributors. The total opening area of ​​each lower end plate satisfies the high-concentration exhaust gas flow rate of 0.2 to 3 m / s.

7. The high- and low-concentration organic waste gas mixing device according to claim 6, characterized in that: The second through hole is circular in shape, and the number and area of ​​the openings are determined according to the volume of the mixed exhaust gas. The total opening area of ​​each mixed exhaust gas distribution plate satisfies that the mixed exhaust gas flow rate is the same as the reverse high-concentration exhaust gas flow rate.

8. The high- and low-concentration organic waste gas mixing device according to claim 1, characterized in that: The low-concentration exhaust gas distributor is a conical cylinder structure with holes opened on the surface.

9. The high- and low-concentration organic waste gas mixing device according to claim 1, characterized in that: A mixed exhaust gas outlet is provided at the top of the inner cylinder; and a high-concentration exhaust gas inlet is provided on the side wall of the outer cylinder.

10. The high- and low-concentration organic waste gas mixing device according to claim 3, characterized in that: A support rod is provided between the upper end plate and the lower end plate.

11. The high- and low-concentration organic waste gas mixing device according to claim 1, characterized in that: The distance between the inner and outer cylinder walls of the annular space is 50 to 300 mm.

12. A method for mixing high- and low-concentration organic waste gases, characterized in that: Using the device as claimed in any one of claims 1 to 11, comprising the following steps: A. Low-concentration exhaust gas is introduced from the bottom of the inner cylinder and evenly distributed upward; high-concentration exhaust gas is introduced from the side wall of the outer cylinder into the annular space between the inner and outer cylinders, and then evenly distributed downward through each stage of high-concentration exhaust gas distributor; B. The low-concentration exhaust gas uniformly upward is reversely mixed with the high-concentration exhaust gas uniformly downward from the first-stage high-concentration exhaust gas distributor to complete the first-stage mixing; C. The mixed exhaust gas flows along the radial direction of the inner cylinder toward the first-stage mixed exhaust gas distribution plate, and then rises along the axial direction of the inner cylinder and passes through the first-stage mixed exhaust gas distribution plate to complete the first-stage second mixing; D. The rising mixed exhaust gas is further mixed in reverse with the uniformly downward high-concentration exhaust gas from the second-stage high-concentration exhaust gas distributor to complete the first mixing of the second stage; E. The mixed exhaust gas flows radially along the inner cylinder toward the second-stage mixed exhaust gas distribution plate, and then rises along the axial direction of the inner cylinder to pass through the second-stage mixed exhaust gas distribution plate to complete the second mixing of the second stage; and so on, the mixed exhaust gas is sequentially mixed with the high-concentration exhaust gas injected from each stage in reverse, and sequentially passes through the mixed exhaust gas distribution plates of each stage to form a return operation, and is finally discharged from the mixed exhaust gas outlet.

13. The method for mixing high- and low-concentration organic waste gases according to claim 12, characterized in that: The upward low-concentration exhaust gas in step A has the same flow rate as the downward first-stage high-concentration exhaust gas.

14. The method for mixing high- and low-concentration organic waste gases according to claim 13, characterized in that: The mixed exhaust gas of each stage going up has the same flow rate as the high-concentration exhaust gas of the next stage going down.

15. The method for mixing high- and low-concentration organic waste gases according to claim 12, characterized in that: In the initial stage of mixing, the distribution time of each level of high-concentration exhaust gas distributor is delayed step by step according to the flow rate of the low-concentration exhaust gas and the size of the inner cylinder.

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