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

Abstract

The invention discloses a high-concentration and low-concentration organic waste gas mixing device and method, the device comprises an inner cylinder structure and an outer cylinder structure, and an annular space is formed between the inner cylinder structure and the outer cylinder structure; 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 uniformly and downwards distributing and horizontally distributing the high-concentration waste gas; each stage of high-concentration waste gas distributor consists of a plurality of tubular structures which are arranged at intervals in a staggered manner along the axial direction of the inner cylinder body; the low-concentration waste gas distributor is arranged at the low-concentration waste gas inlet at the bottom of the inner barrel, is positioned in the area on the other side of the first-stage high-concentration waste gas distributor, and is used for uniformly distributing low-concentration waste gas into the first-stage waste gas channel; the mixed waste gas distribution plates are arranged in a multi-stage mode and located in the inner barrel, each mixed waste gas distribution plate occupies the whole space of the cross section of the inner barrel, a half area of each mixed waste gas distribution plate is provided with holes, and the hole areas correspond to the high-concentration waste gas distributors in position; and the spiral blade is fixed at the top of each stage of high-concentration waste gas distributor and is positioned right below the opening area of the mixed waste gas distribution plate.

Description

Technical Field

[0001] The present invention relates to the technical field of environmental waste gas treatment, and in particular to a high-concentration 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 concentration distribution of the mixed waste gas 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 purpose of the present invention is to provide a high-concentration and low-concentration organic waste gas mixing device and 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 equipment, and is particularly suitable for occasions where the organic waste gas concentration and flow rate differ greatly.

[0009] To achieve the above-mentioned purpose, according to the first aspect of the present invention, the present invention provides a high-concentration 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 connected to the annular space, and is used to receive the high-concentration waste gas in the annular space and evenly distribute the high-concentration waste gas downward and horizontally; each stage of the high-concentration waste gas distributor is composed of a plurality of tubular structures, and is staggeredly arranged along the axial direction of the inner cylinder; a low-concentration waste gas distributor is arranged in a plurality of tubular structures, and is staggeredly arranged along the axial direction of the inner cylinder; a high ... low-concentration waste gas distributor is arranged in a plurality of tubular structures, and is staggeredly arranged along the axial direction of the inner cylinder; a high-concentration waste gas distributor is arranged in a plurality of tubular structures, and is staggeredly arranged along the axial direction of the inner cylinder; a high-concentration waste gas distributor is arranged in a plurality of tubular structures, and is staggeredly arranged along the axial direction of the inner cylinder; a high-concent A high-concentration exhaust gas distributor, which is arranged at the low-concentration exhaust gas inlet at the bottom of the inner cylinder and is located at the other side of the first-stage high-concentration exhaust gas distributor, and is used to evenly distribute the low-concentration exhaust gas to the first-stage exhaust gas channel; a mixed exhaust gas distribution plate, which is arranged in multiple stages and is located in the inner cylinder, each mixed exhaust gas distribution plate occupies the entire space of the cross-section of the inner cylinder and half of the area is an open hole arrangement, and the open hole area corresponds to the position of the high-concentration exhaust gas distributor; a spiral blade, which is fixed at the top of each stage of the high-concentration exhaust gas distributor and is located directly below the open hole area of ​​the mixed exhaust gas distribution plate.

[0010] Furthermore, in the above technical solution, 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 deflection channel of the mixed exhaust gas.

[0011] Furthermore, in the above technical solution, the high-concentration exhaust gas distributor includes: a first distribution pipe, which is multiple in number and extends from the inner wall of the inner cylinder to the axis of the inner cylinder, and the first through hole is opened at the bottom and side of the first distribution pipe; a second distribution pipe, which may be shorter than the first distribution pipe and is evenly spaced apart from the first distribution pipe in the horizontal direction; the first through hole is opened at the bottom and side of the second distribution pipe.

[0012] Furthermore, in the above technical solution, the mixed exhaust gas distribution plate may be a horizontally arranged plate structure, and a second through hole is provided in the region of the plate corresponding to the first distribution pipe and the second distribution pipe.

[0013] Furthermore, in the above technical solution, the mixed exhaust gas distribution plate can be fixed on the wall surface of the inner cylinder.

[0014] Furthermore, in the above technical solution, the equivalent cross-sectional diameters of the first distribution pipe and the second distribution pipe can be 40 to 200 mm; the shape of the first through hole can be circular, and the equivalent opening diameter can be 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 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 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 high-concentration exhaust gas flow rate.

[0016] Furthermore, in the above technical solution, the spiral blades can be evenly distributed at the upper ends of the first distribution pipe and the second distribution pipe. The spiral blades are conical as a whole, and the large end at the bottom is fixedly connected to the first distribution pipe and the second distribution pipe. The small end at the top can be 20 to 100 mm away from the opening area of ​​the mixed exhaust gas distribution plate.

[0017] Furthermore, in the above technical solution, the diameter of the bottom large end can be 0.8 to 1.2 times the diameter of the distribution pipe; the center distance between two adjacent spiral blades can be 1.2 to 2 times the diameter of the bottom large end; the number of spiral blades can be determined according to the length of the distribution pipe and the center distance of the spiral blades.

[0018] Furthermore, in the above technical solution, the low-concentration exhaust gas distributor can be a conical cylinder structure with holes opened on the surface.

[0019] 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.

[0020] Furthermore, in the above technical solution, a support rod may be provided between the inner cylinder and the outer cylinder.

[0021] Furthermore, in the above technical solution, the distance between the inner and outer cylinder walls of the annular space can be 50 to 300 mm; the distance between the high-concentration exhaust gas distributor and the mixed exhaust gas distribution plate above it can be 0.3 to 0.5 times the distance between adjacent mixed exhaust gas distribution plates.

[0022] According to the second aspect of the present invention, the present invention provides a method for mixing high-concentration and low-concentration organic waste gases, using the aforementioned device, including the following steps: A. Passing low-concentration waste gas from the bottom of the inner cylinder and evenly distributing it to the first-stage waste gas channel; passing 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 and horizontally through each stage of high-concentration waste gas distributor; B. The evenly distributed low-concentration waste gas contacts and freely diffuses with the high-concentration waste gas evenly distributed downward and horizontally from the first-stage high-concentration waste gas distributor, completing the first-stage first mixing; C. When the mixed waste gas flows through the spiral blades, the gas flows upward around the spiral blades, increasing the turbulence intensity of the local airflow, completing the first-stage second mixing; D. The spiral airflow further rises along the axial direction of the inner cylinder and passes through the first-stage mixed waste gas distribution plate, and the gas is redistributed and the first-stage third mixing is completed; E. By analogy, the mixed waste gas is freely diffused and mixed with the high-concentration waste gas injected downward and horizontally from each stage in turn, and forms a return operation through the spiral blades and mixed waste gas distribution plates of each stage in turn, and is finally discharged from the mixed waste gas outlet.

[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 is injected into the mixed exhaust gas in different directions horizontally and vertically downward through a multi-stage high-concentration exhaust gas distributor. In the process of free diffusion, the airflows in different directions contact and mix to form a vortex effect; the large-flow low-concentration exhaust gas carries multiple small-flow high-concentration exhaust gases to continue to flow toward the opening area of ​​the mixed exhaust gas distribution plate. In this process, when the gas flows through the spiral blades on the high-concentration exhaust gas distributor, the gas flows upward around the spiral blades, which increases the turbulence intensity of the local airflow and improves the mass transfer efficiency between the high-concentration and low-concentration exhaust gases;

[0027] 3) The mixed exhaust gas distribution plate of the present invention divides 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 within 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 exhaust gas is evenly distributed, which is conducive to the efficient and stable operation of the subsequent organic exhaust gas treatment device, and is particularly suitable for occasions where the organic exhaust 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-concentration 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 Schematic diagram of the top view of the mixed exhaust gas distribution plate.

[0034] Figure 3 yes Figure 1 Schematic diagram of the overhead view of the medium and high concentration exhaust gas distributor.

[0035] Description of main reference numerals:

[0036] 1-outer cylinder, 11-annular space, 12-support rod, 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-first distribution pipe, 82-second distribution pipe, 83-first through hole, 84-spiral blade, 9-mixed exhaust gas distribution plate, 9A-opening area, 9B-non-opening area, 91-second through hole, 10-low-concentration exhaust gas distributor. DETAILED DESCRIPTION

[0037] 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.

[0038] 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.

[0039] 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.

[0040] 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.

[0041] Example 1

[0042] like Figures 1 to 3As shown, this embodiment provides a high-concentration and 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, an annular space 11 is formed between the inner and outer cylinders, and a support rod 12 can be arranged between the inner and outer cylinders. Specifically, an upper head 4 can be arranged at the upper end of the inner and outer cylinders, and a lower head 3 can be arranged at the lower end. A low-concentration waste gas inlet 5 is arranged on the lower head 3, a high-concentration waste gas inlet 6 is arranged on the side wall of the outer cylinder 1, and a mixed waste gas outlet 7 is arranged 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 and horizontally. Each stage of the high-concentration waste gas distributor 8 is composed of a plurality of tubular structures, and is arranged alternately along the axial direction of the inner cylinder 2. The low-concentration exhaust gas distributor 10 is arranged at the low-concentration exhaust gas inlet 5 at the bottom of the inner cylinder 2, and is located in the other side area of ​​the first-stage high-concentration exhaust gas distributor, and is used to evenly distribute the low-concentration exhaust gas to the first-stage exhaust gas channel. Corresponding to the high-concentration exhaust gas distributor 8, the mixed exhaust gas distribution plate 9 is also multi-stage and located in the inner cylinder 2. Specifically, each mixed exhaust gas distribution plate 9 occupies the entire space of the cross-section of the inner cylinder 2 and half of the area is an opening setting, and the opening area corresponds to the position of the high-concentration exhaust gas distributor 8. The spiral blade of this embodiment is fixed to the top of each stage of the high-concentration exhaust gas distributor 8 and is located directly below the opening area 9A of the mixed exhaust gas distribution plate 9.

[0043] Further Figure 1 As shown, in this embodiment, the high-concentration exhaust gas distributor 8 and the mixed exhaust gas distribution plate 9 of each stage are arranged at different heights, and both are fixedly connected to the wall of the inner cylinder 2 respectively; there are two or more high-concentration exhaust gas distributors 8 and mixed exhaust gas distribution plates 9; each stage of high-concentration exhaust gas distributors 8 and mixed exhaust gas distribution plates 9 are arranged at a certain distance from bottom to top along the inner cylinder 2, preferably but not restrictively, the distance between the high-concentration exhaust gas distributor 8 and the mixed exhaust gas distribution plate 9 above it is 0.3 to 0.5 times the distance between adjacent mixed exhaust gas distribution plates 9. Through such an arrangement and the staggered arrangement of the opening areas on the mixed exhaust gas distribution plate 9, the mixed exhaust gas flow channel (that is, the space enclosed by the inner cylinder 2 and the upper and lower heads) is divided 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.

[0044] In the mixing device of this embodiment, the high-concentration exhaust gas is dispersed and injected into the low-concentration exhaust gas step by step through the multi-stage high-concentration exhaust gas distributor, instead of injecting the 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, the downward and horizontal high-concentration exhaust gas is fully diffused, and is fully contacted and mixed with the mixed exhaust gas from the upper exhaust channel through the multi-stage high-concentration exhaust gas distributor, which can effectively improve the mass transfer efficiency between high-concentration and low-concentration exhaust gases, and through water The interaction of horizontal and vertical airflows, where large-flow low-concentration exhaust gas carries small-flow high-concentration exhaust gas to form local vortices, can further enhance the uniform mixing effect of the two; furthermore, when flowing through the spiral blades on the high-concentration exhaust gas distributor, the gas can flow upward around the spiral blades, increasing the turbulence intensity of the local airflow, which can improve the mass transfer efficiency between high- and low-concentration exhaust gases; in the process of exhaust gas mixing and circulation, the mixed exhaust gas distribution plate divides the mixed exhaust gas flow channel into several connected areas, which can increase the circulation length of the mixed exhaust gas in a limited space, extend the mixing time, and further improve the mass transfer efficiency.

[0045] Further Figure 1 , 3 As shown, 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. The high-concentration exhaust gas distributor 8 further includes a first distribution pipe 81 and a second distribution pipe 82, wherein the number of the first distribution pipes 81 is multiple and extends from the inner wall of the inner cylinder 2 to the axis of the inner cylinder, and the bottom and side of the first distribution pipe 81 are provided with a first through hole 83. The length of the second distribution pipe 82 is less than the first distribution pipe and is evenly spaced from the first distribution pipe in the horizontal direction; the bottom and side of the second distribution pipe 82 are also provided with a first through hole 83. The first through holes 83 are evenly distributed, and the opening shape can be circular, square or diamond, etc., preferably circular; further, the cross-sectional equivalent diameter of the first distribution pipe 81 and the second distribution pipe 82 is 40-200 mm; when the shape of the first through hole is circular, the opening equivalent diameter is preferably 10-40 mm; 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, and the total opening area satisfies the high-concentration exhaust gas flow rate of 0.2-3 m / s, preferably 0.5-1.5 m / s. It should be noted here that the number of grades of the high-concentration exhaust gas distributor 8 of 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 first distribution pipe 81 and the second distribution pipe 82 in the high-concentration exhaust gas distributors 8 at each level can be the same, or the total opening area of ​​the high-concentration exhaust gas distributor 8 can be gradually reduced from bottom to top.

[0046] Further Figure 1 ,3 As shown, the spiral blades 84 are evenly distributed at the upper ends of the first distribution pipe 81 and the second distribution pipe 82, and the spiral blades are tapered as a whole (refer to Figure 1 ), the bottom large end is fixedly connected to the first distribution pipe 81 and the second distribution pipe 82, and the top small end is 20 to 100 mm away from the opening area 9A of the mixed exhaust gas distribution plate 9. Preferably, but not restrictively, the diameter of the bottom large end is 0.8 to 1.2 times the diameter of the distribution pipe; the center distance between two adjacent spiral blades is 1.2 to 2 times the diameter of the bottom large end; the number of spiral blades is determined according to the length of the distribution pipe and the center distance of the spiral blades. The inventor has found through experimental research that by using the overall conical spiral blades and the setting position of this embodiment, the mixed exhaust gas has a high degree of turbulence before entering the next stage of the exhaust gas channel. Especially for occasions with a high difference in exhaust gas concentration, the turbulence generated by the spiral blades makes the mixing and mass transfer effect of the two obvious.

[0047] Further Figure 1 , 2 As shown, the mixed exhaust gas distribution plate 9 is a horizontally arranged plate structure, and the number of the plates is one less than the number of high-concentration exhaust gas distributors, and the distance between two adjacent mixed exhaust gas distribution plates 9 can be 0.3 to 1 times the radius of the inner cylinder. A second through hole 91 is provided in the area corresponding to the first distribution pipe 81 and the second distribution pipe 82 on the plate body. The mixed exhaust gas distribution plate 9 can be fixed on the wall of the inner cylinder. 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 high-concentration exhaust gas flow rate, that is, the mixed concentration exhaust gas flow rate is 0.2 to 3 m / s, preferably 0.5 to 1.5 m / s. In this embodiment, the total opening area of ​​the mixed exhaust gas distribution plates 9 at all levels is the same, and the opening diameter, number and arrangement method can be the same or different.

[0048] 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 distribute the low-concentration exhaust gas from the bottom of the inner cylinder to the first-stage exhaust gas channel. It should be noted here that, considering the problem of uniform diffusion, this embodiment sets the low-concentration exhaust gas distributor 10 away from the setting position of the first-stage high-concentration exhaust gas distributor 8, that is, the low-concentration exhaust gas distributor 10 is set at the bottom of the left side of the inner cylinder, and the first-stage high-concentration exhaust gas distributor 8 is set on the right side of the inner cylinder, so that the low-concentration exhaust gas entering can be fully diffused and then contacted and mixed with the high-concentration exhaust gas that runs evenly downward and horizontally. 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.

[0049] 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.

[0050] Example 2

[0051] This embodiment provides a method for mixing high-concentration and low-concentration organic waste gas. The aforementioned 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 first distribution pipe 81 and the second distribution pipe 82 of 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 and diffuses evenly through the low-concentration waste gas distributor 10. The subsequent mixing process of high- and low-concentration waste gas includes the following steps:

[0052] Step S101, low-concentration exhaust gas is introduced from the bottom of the inner cylinder 2 and evenly distributed to the first-stage exhaust gas channel; 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 and horizontally through each stage of high-concentration exhaust gas distributor. The low-concentration exhaust gas is first effectively diffused in the first-stage exhaust gas channel and contacts with the high-concentration exhaust gas distributed vertically downward and horizontally;

[0053] Step S102, the evenly distributed low-concentration exhaust gas contacts and freely diffuses with the evenly downward and horizontally distributed high-concentration exhaust gas from the first-stage high-concentration exhaust gas distributor 8, completing the first stage of first mixing. The freely diffused large-flow low-concentration exhaust gas carries the small-flow high-concentration exhaust gas to form a local vortex, which can enhance the even mixing effect of the two;

[0054] Step S103, when the mixed exhaust gas flows through the spiral blade 84, the gas flows upward around the spiral blade, increasing the turbulence intensity of the local airflow, completing the first stage second mixing;

[0055] Step S104, the spiral airflow further rises along the axial direction of the inner cylinder 2 and passes through the first-stage mixed exhaust gas distribution plate 9, the gas is redistributed and the first-stage third mixing is completed;

[0056] Step S104, the rising mixed exhaust gas is further reversely mixed with a portion of high-concentration exhaust gas uniformly downward from the second-stage high-concentration exhaust gas distributor, and at the same time, another portion of the high-concentration exhaust gas is horizontally diffused to complete the first mixing of the second stage;

[0057] Step S105, and so on, the mixed exhaust gas is freely diffused and mixed with the high-concentration exhaust gas injected downward and horizontally from each level in turn, and passes through the spiral blades and mixed exhaust gas distribution plates of each level in turn 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 level is equivalent to that of the high-concentration exhaust gas at the next level. The eddy effect formed by the free diffusion of exhaust gas in different directions and the turbulence effect formed at the spiral blades can effectively improve the mass transfer efficiency between high-concentration 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.

[0058] 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 of 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 diffusion path (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.

[0059] 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.

[0060] 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 device for mixing high-concentration and low-concentration organic waste gas, 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 is arranged in multiple stages and is located in the inner cylinder and is communicated with the annular space, and is used to receive the high-concentration exhaust gas in the annular space and evenly distribute the high-concentration exhaust gas downward and horizontally; each stage of the high-concentration exhaust gas distributor is composed of a plurality of tubular structures, 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 at the other side of the first-stage high-concentration exhaust gas distributor, and is used to evenly distribute the low-concentration exhaust gas to the first-stage exhaust gas channel; Mixed exhaust gas distribution plates, which are arranged in multiple stages and are located in the inner cylinder, each mixed exhaust gas distribution plate occupies the entire space of the cross section of the inner cylinder and half of the area is open, and the open area corresponds to the position of the high-concentration exhaust gas distributor; The spiral blade is fixed on the top of each stage of the high-concentration exhaust gas distributor and is located directly below the opening area of ​​the mixed exhaust gas distribution plate.

2. The high-concentration and low-concentration organic waste gas mixing device according to claim 1 is characterized in that: The mixed exhaust gas distribution plate divides 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-concentration and low-concentration organic waste gas mixing device according to claim 1 is characterized in that: The high-concentration exhaust gas distributor comprises: There are a plurality of first distribution pipes extending from the inner wall of the inner cylinder toward the axis of the inner cylinder, and first through holes are provided at the bottom and side of the first distribution pipes; The second distribution pipe is shorter than the first distribution pipe and is evenly spaced from the first distribution pipe in the horizontal direction; the first through hole is formed at the bottom and side of the second distribution pipe.

4. The high-concentration 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 plate structure, and a second through hole is provided in the area of ​​the plate corresponding to the first distribution pipe and the second distribution pipe.

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

6. The high-concentration and low-concentration organic waste gas mixing device according to claim 3 is characterized in that: The cross-sectional equivalent diameters of the first distribution pipe and the second distribution pipe are 40 to 200 mm; the first through hole is circular in shape, and the opening equivalent 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 satisfies the high-concentration exhaust gas flow rate of 0.2 to 3 m / s.

7. The high-concentration and low-concentration organic waste gas mixing device according to claim 4 is 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 flow rate of the mixed exhaust gas is the same as that of the high-concentration exhaust gas.

8. The high-concentration and low-concentration organic waste gas mixing device according to claim 3 is characterized in that: The spiral blades are evenly distributed on the upper ends of the first and second distribution pipes. The spiral blades are tapered as a whole. The bottom large end is fixedly connected to the first and second distribution pipes, and the top small end is 20 to 100 mm away from the opening area of ​​the mixed exhaust gas distribution plate.

9. The high-concentration and low-concentration organic waste gas mixing device according to claim 8, characterized in that: The bottom large end diameter is 0.8 to 1.2 times the distribution pipe diameter; the center distance between two adjacent spiral blades is 1.2 to 2 times the bottom large end diameter; the number of spiral blades is determined according to the length of the distribution pipe and the center distance of the spiral blades.

10. The high-concentration 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.

11. The high-concentration 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.

12. The high-concentration and low-concentration organic waste gas mixing device according to claim 1, characterized in that: A support rod is arranged between the inner cylinder and the outer cylinder.

13. 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; the distance between the high-concentration exhaust gas distributor and the mixed exhaust gas distribution plate above it is 0.3 to 0.5 times the distance between adjacent mixed exhaust gas distribution plates.

14. A method for mixing high-concentration and low-concentration organic waste gas, characterized in that: Using the device as claimed in any one of claims 1 to 13, comprising the following steps: A. Low-concentration exhaust gas is introduced from the bottom of the inner cylinder and evenly distributed to the first-stage exhaust gas channel; 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 and horizontally through each stage of high-concentration exhaust gas distributor; B. The evenly distributed low-concentration exhaust gas contacts and freely diffuses with the evenly downward and horizontally distributed high-concentration exhaust gas from the first-stage high-concentration exhaust gas distributor, completing the first-stage mixing; C. When the mixed exhaust gas flows through the spiral blades, the gas flows upward around the spiral blades, increasing the turbulence intensity of the local airflow and completing the first-stage second mixing; D. The spiral airflow further rises along the axial direction of the inner cylinder and passes through the first-stage mixed exhaust gas distribution plate, and the gas is redistributed and the third mixing of the first stage is completed; E. By analogy, the mixed exhaust gas freely diffuses and mixes with the high-concentration exhaust gas injected downward and horizontally from each stage, and passes through the spiral blades and 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.

15. The method for mixing high-concentration and low-concentration organic waste gases according to claim 14, 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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