Equipment for improving efficiency of cyclone separator through two-way air exhaust

Abstract

When the equipment for improving the efficiency of the cyclone separator through two-way air extraction is used, air extraction is conducted through the air extraction device, external air enters the outlet air extraction ejector through the main air extraction pipeline, and air in the barrel is extracted to the outlet air extraction pipe through the annular gap between the outlet inner pipe and the outlet outer pipe; the air enters an outlet air exhaust ejector through an outlet air exhaust branch pipeline, external air and air in the barrel body enter a discharge port air exhaust ejector through a first connecting pipeline, and air in the middle ash hopper enters the discharge port air exhaust ejector through a discharge port; external air, gas in the barrel and gas in the middle ash hopper enter the stock bin through a second connecting pipeline and an air extractor, purified gas obtained after dust is completely removed through a dust remover is diffused to a centralized diffusion system through a total flow meter, and dust in the stock bin is discharged through a stock bin discharging valve. The secondary vortex can be inhibited and weakened, the cyclone separation efficiency is improved, and the running resistance is reduced.

Description

Technical Field

[0001] This invention relates to the field of gas-solid separation technology in the heterogeneous separation field of chemical engineering, and particularly to the field of cyclone separator technology, specifically a device for improving the efficiency of a cyclone separator through dual-channel air extraction. Background Technology

[0002] As is well known, cyclone separators possess advantages such as simple structure, no moving parts, high separation efficiency, convenient maintenance, and the ability to operate stably under harsh conditions such as high temperature and high pressure. They have been widely used in industries such as petroleum, chemical, steel, coal chemical, cement, environmental protection, and food processing, and can be considered irreplaceable in the field of heterogeneous separation for a long time. Although cyclone separators have a simple structure, their internal motion is extremely complex, belonging to two-phase or three-phase three-dimensional turbulent flow, making theoretical research very difficult, and to this day, its precise motion laws cannot be fully grasped. Nevertheless, research on cyclone separators continues both domestically and internationally, with research methods and tools evolving in line with the development of science and technology.

[0003] Current research indicates that, in addition to the main swirling flow (including inner and outer swirling flows), secondary vortices are prevalent within cyclone separators. These secondary vortices, composed of axial velocity νz and radial velocity νr, cause severe back-mixing of solid particles within the separator, significantly impacting its performance, particularly separation efficiency. The main localized secondary vortices within the cyclone are: 1) longitudinal circulation in the annular space; 2) short-circuit flow at the lower end of the outlet pipe; 3) localized vortices in the outer swirling flow; and 4) bottom entrainment. Therefore, developing a method to minimize secondary vortices and reduce solid dust particle back-mixing is an important direction for improving cyclone separation efficiency.

[0004] Researchers have found that structural optimization of cyclones generally still makes it difficult to completely eliminate the secondary vortices inside the cyclone. However, theoretical analysis and practical applications of cyclones have confirmed that extracting a portion of the gas from inside the cyclone can significantly improve the internal flow field, thereby greatly improving the efficiency of the cyclone separator, especially the separation efficiency of fine particles.

[0005] For example, Chinese invention patent "Adjustment Structure for Circulation Flow Rate of Circulating Fluidized Bed Boiler" (authorization announcement number CN115289462B) discloses an adjustment structure for the circulation flow rate of a circulating fluidized bed boiler, including a cyclone separator, a ventilation pipe, and an air inlet and exhaust assembly. The ventilation pipe passes through the side wall of the material leg of the cyclone separator, with one end located at the upper inner end of the material leg and having a ventilation opening, and the other end located outside the material leg. The air inlet and exhaust assembly is connected to the other end of the ventilation pipe, used to introduce air into the upper inner end of the material leg through the ventilation pipe to increase the pressure at the upper inner end of the material leg, and to exhaust air from the upper inner end of the material leg through the ventilation pipe to reduce the pressure at the upper inner end of the material leg. This invention can adjust the circulation flow rate of a circulating fluidized bed boiler, with fast response, easy adjustment, and simple operation. According to the patent description, the efficiency of the cyclone separator can be adjusted by drawing air from and drawing air from the cyclone material leg (and thus adjusting the circulation flow rate of the circulating fluidized bed boiler); however, the patent only provides a qualitative description without quantitative data support, making it difficult to grasp the trend of the effect of air extraction on the efficiency of the cyclone separator.

[0006] Chinese invention patent application "Recirculating Cyclone Separator" (publication number CN102553732A) discloses a recirculating cyclone separator, including a main shell comprising an upper cylindrical body, a top cover plate, and a lower inverted conical body. A recirculating inlet is tangentially installed at the upper end of the cylindrical body, and a main air inlet is tangentially installed in the middle of the cylindrical body. An exhaust core pipe is installed in the middle of the top cover plate and extends into the cylindrical body. A gas outlet is installed above the exhaust core pipe, and an extraction port is located at the top side of the exhaust core pipe. An ash discharge port is located at the lower end of the inverted conical body, with its lower end connected to an ash hopper. The extraction port forms a recirculating connection with the recirculating inlet via pipelines and a fan. This invention exhibits a small scale-up effect and low pressure drop, effectively eliminating the adverse effects of secondary flow near the inlet on separation performance. It can completely separate particles larger than 3 micrometers, with a separation efficiency of over 98% for particles smaller than 3 micrometers. It can replace bag filters and electrostatic precipitators for end-of-pipe dust removal of dusty gases. According to the patent description, air extraction can effectively eliminate secondary eddies near the cyclone inlet. However, the main secondary eddies of the cyclone are concentrated near the cyclone outlet. Therefore, although this air extraction scheme can improve the separation efficiency to a certain extent, it does not completely eliminate the main secondary eddies and needs further improvement.

[0007] Chinese invention patent "Cyclone Separator Impurity Removal Device" (authorization announcement number CN210386235U) discloses a cyclone separator impurity removal device, including a support foot connected to the ground, a separation cylinder on the support foot, the separation cylinder including a cylindrical air guide tube and an inverted conical return tube, the return tube being connected to the lower end of the air guide tube, a dust collection chamber at the bottom of the return tube, an air inlet pipe extending tangentially along the outer periphery of the air guide tube at the top of the side of the air guide tube, an air outlet pipe at the top of the air guide tube extending downward inside the air guide tube, and a negative pressure pipe for outward air extraction on the return tube, the negative pressure pipe being connected to the end of the return tube away from the air guide tube. This device can remove some of the lighter dust separated in the cyclone separator, which is beneficial to improving the purity of subsequent products. According to the patent description, extracting air from the bottom of the cyclone cone can remove some of the difficult-to-separate lighter dust separated in the cyclone separator, which can improve the separation efficiency and thus improve the purity of the subsequent products from the cyclone. However, drawing air from the bottom of the cyclone cone (through the extraction pipe) can easily disrupt the internal flow field of the cyclone and increase the possibility of blockage at the discharge port, thus having limited effect on improving the separation efficiency of the cyclone.

[0008] As industrial plants grow larger, the traditional solution of using multiple small-diameter cyclones (less than 800mm) in parallel is encountering more and more engineering problems. The structural complexity, operational stability, adaptability to operating conditions, and cost-effectiveness of these cyclones have all revealed many shortcomings. Therefore, it is essential to improve the separation efficiency of large cyclone separators and reduce their operating resistance. For large cyclone separators with diameters greater than 2000mm, the influence of various secondary eddies inside the separator is more severe. Compared with small-diameter cyclones, their separation performance is significantly reduced under the same operating conditions. Therefore, the research and development of cyclone separators, especially large cyclone separators, still has important practical significance.

[0009] Therefore, it is desirable to provide a device that improves the efficiency of a cyclone separator by air extraction, which can suppress and weaken secondary eddies, improve cyclone separation efficiency, and reduce operating resistance. Summary of the Invention

[0010] In order to overcome the shortcomings of the prior art, one object of the present invention is to provide a device for improving the efficiency of a cyclone separator through dual-channel air extraction, which can suppress and weaken secondary eddies, improve cyclone separation efficiency, reduce operating resistance, and is suitable for large-scale application.

[0011] Another objective of this invention is to provide a device for improving the efficiency of a cyclone separator through dual-channel air extraction. This device is ingeniously designed, has a simple structure, is easy to manufacture, has low manufacturing costs, and is suitable for large-scale application.

[0012] To achieve the above objectives, the present invention provides a device for improving the efficiency of a cyclone separator through dual-channel air extraction, comprising a cyclone separator, wherein the cyclone separator includes a cyclone inlet, a cylindrical body, a cylindrical end cap, a cone, an intermediate ash hopper, a discharge port, and a cyclone outlet. The cylindrical body, the cone, and the intermediate ash hopper are all vertically arranged and coaxially aligned. The diameter of the upper end of the cone is larger than the diameter of the lower end of the cone. The discharge port is located in the lower end of the intermediate ash hopper, and the lower end of the cone is located on the upper end of the intermediate ash hopper. The lower end of the cylindrical body is... At the upper end of the cone, the cylindrical end cap is disposed at the upper end of the cylinder, and the cyclone inlet is tangent to the upper part of the cylinder at a 180° volute. The device for improving the efficiency of the cyclone separator through dual-path air extraction further includes an outlet air extraction pipe, an outlet air extraction branch pipe, a branch regulating valve, a branch flow meter, a main air extraction pipe, a main regulating valve, a main flow meter, an outlet air extraction ejector, a first connecting pipe, a discharge port air extraction ejector, a second connecting pipe, an air extraction device, a hopper, a hopper discharge valve, a dust collector, and a total flow meter, wherein:

[0013] The cyclone separator further includes an inner outlet pipe, an outer outlet pipe, and a pipe end cap. Both the inner outlet pipe and the outer outlet pipe are vertically arranged and coaxially. The outer outlet pipe is vertically inserted into the pipe end cap and coaxially arranged with the cylinder body. The upper end of the outer outlet pipe protrudes upward from the pipe end cap. The pipe end cap is located on the upper end of the outer outlet pipe. The lower end of the outer outlet pipe is located in the cylinder body. The inner outlet pipe is vertically inserted into the pipe end cap. The upper end of the inner outlet pipe protrudes upward from the pipe end cap. The cyclone outlet is located on the upper end of the inner outlet pipe. The lower end of the inner outlet pipe protrudes downward from the lower end of the outer outlet pipe and is located in the cylinder body.

[0014] The outlet outer pipe is connected to the outlet exhaust branch pipe through the outlet exhaust pipe. The branch regulating valve and the branch flow meter are both installed in the outlet exhaust branch pipe. The main exhaust pipe and the outlet exhaust branch pipe are both connected to the first connecting pipe through the outlet exhaust ejector pipe. The main regulating valve and the main flow meter are both installed in the main exhaust pipe. The first connecting pipe and the discharge port are both connected to the second connecting pipe through the discharge port exhaust ejector pipe. The second connecting pipe is connected to the top of the silo through the exhaust device pipe. The silo discharge valve is installed in the bottom of the silo. The top of the silo is connected to the total flow meter through the dust collector pipe.

[0015] Preferably, the ratio of the diameter D1 of the inner outlet tube to the diameter D0 of the cylinder is D1 / D0 = 0.35 to 0.60, and the relationship between the diameter D2 of the outer outlet tube and the diameter D1 of the inner outlet tube is D2-D1 = 25mm to 60mm.

[0016] Preferably, the ratio of the depth h1 into the cylinder of the outer outlet pipe to the depth h0 into the cylinder of the inner outlet pipe is h1 / h0 = 0.65 to 0.90.

[0017] Preferably, both the outlet suction ejector and the discharge port suction ejector include a receiving port, an oblique square connecting circle, a conveying pipe, an inlet, a throat, and an ejection outlet. The conveying pipe and the throat are both arranged along the left-right direction. The throat is wider at the left end and narrower at the right end, and is located inside the left end of the conveying pipe. The conveying pipe is located between the inlet and the ejection outlet and connects to both. The oblique square connecting circle is inclined downwards and to the right from left to right, and its lower end is inclined along the direction of the oblique square connecting circle. The material receiving port is located at the upper end of the inclined square-shaped duct, and the main exhaust pipe and the outlet exhaust branch pipe are respectively connected to the inlet and the receiving port of the outlet exhaust ejector. The ejector outlet pipe of the outlet exhaust ejector is connected to the first connecting pipe. The first connecting pipe and the discharge port are respectively connected to the inlet and the receiving port of the discharge port exhaust ejector. The ejector outlet pipe of the discharge port exhaust ejector is connected to the second connecting pipe.

[0018] More preferably, the ratio of the diameter d1 of the right end of the throat tube to the diameter d0 of the delivery tube is d1 / d0 = 0.20 to 0.45.

[0019] Preferably, the branch regulating valve and the branch flow meter are used to regulate the outlet air volume drawn from the outlet exhaust pipe, the outlet air volume being 0.6% to 1.3% of the volume of the cyclone inlet air volume.

[0020] Preferably, the branch regulating valve and the branch flow meter are used to regulate the outlet air volume drawn from the outlet exhaust pipe, the main regulating valve and the main flow meter are used to regulate the main air volume drawn from the main exhaust pipe, and the total flow meter is used to regulate the total air volume drawn by the exhaust device. The discharge port air volume = the total air volume - the outlet air volume - the main air volume, and the discharge port air volume is 1.5% to 6.2% of the volume of the cyclone inlet air volume.

[0021] Preferably, the branch flow meter is an orifice plate flow meter, and the main flow meter and the total flow meter are both rotor flow meters.

[0022] Preferably, the air extraction device is an induced draft fan.

[0023] Preferably, the dust collector is a bag filter.

[0024] The main beneficial effects of this invention are:

[0025] 1. In use, the dual-extraction cyclone separator efficiency improvement device of the present invention extracts air through an extraction device. External air enters the outlet extraction ejector through the main extraction pipe. Gas inside the cylinder is extracted to the outlet extraction pipe through the annular gap between the outlet inner pipe and the outlet outer pipe, and then enters the outlet extraction ejector through the outlet extraction branch pipe. External air and gas inside the cylinder enter the discharge port extraction ejector through the first connecting pipe. Gas inside the intermediate ash hopper enters the discharge port extraction ejector through the discharge port. External air, gas inside the cylinder, and gas inside the intermediate ash hopper enter the hopper through the second connecting pipe and the extraction device. Thus, the dust collected by the cyclone separator and the dust contained in the gas extracted by the outlet extraction pipe are pneumatically conveyed to the hopper by the extraction device. The purified gas after the dust is removed by the dust collector is discharged to a centralized venting system, for example, through the total flow meter. The dust in the hopper is discharged through the hopper discharge valve. Therefore, it can suppress and weaken secondary eddies, improve cyclone separation efficiency, reduce operating resistance, and is suitable for large-scale promotion and application.

[0026] 2. In use, the dual-extraction cyclone separator efficiency improvement device of the present invention uses an extraction device to extract air. External air enters the outlet extraction ejector through the main extraction pipe. Gas inside the cylinder is extracted to the outlet extraction pipe through the annular gap between the outlet inner pipe and the outlet outer pipe, and then enters the outlet extraction ejector through the outlet extraction branch pipe. External air and gas inside the cylinder enter the discharge port extraction ejector through the first connecting pipe. Gas inside the intermediate ash hopper enters the discharge port extraction ejector through the discharge port. External air, gas inside the cylinder, and gas inside the intermediate ash hopper enter the hopper through the second connecting pipe and the extraction device. Thus, the dust collected by the cyclone separator and the dust contained in the gas extracted by the outlet extraction pipe are pneumatically conveyed to the hopper by the extraction device. The purified gas after the dust is removed by the dust collector is discharged to, for example, a centralized venting system through the total flow meter. The dust in the hopper is discharged through the hopper discharge valve. Therefore, its design is ingenious, its structure is simple, its manufacturing is convenient, and its manufacturing cost is low, making it suitable for large-scale promotion and application.

[0027] These and other objects, features and advantages of the present invention will be fully apparent from the following detailed description and drawings, and can be achieved by the means, devices and combinations thereof specifically pointed out in the summary of the invention. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of the first specific embodiment of the device for improving the efficiency of a cyclone separator through dual-channel air extraction according to the present invention.

[0029] Figure 2 yes Figure 1 A front view schematic diagram of the cyclone separator of the first specific embodiment shown.

[0030] Figure 3 yes Figure 1 A top view of the cyclone separator of the first specific embodiment is shown.

[0031] Figure 4 yes Figure 1 The diagram shows a front sectional view of the outlet ejector of the first specific embodiment.

[0032] Figure 5 yes Figure 1 The diagram shows a comparison of the separation efficiency of the first specific embodiment with that of the Buell B-type cyclone separator from the United States.

[0033] Figure 6 yes Figure 1 The diagram shows a comparison of the operating pressure drop test results of the first specific embodiment and the Buell Type B cyclone separator from the United States.

[0034] (Explanation of reference numerals in the attached image)

[0035] 1 Cyclone separator; 101 Cyclone inlet; 102 Cyclone body; 103 Cyclone end cap; 104 Cone; 105 Intermediate ash hopper; 106 Discharge port; 107 Cyclone outlet; 108 Inner outlet pipe; 109 Outer outlet pipe; 110 Pipe end cap;

[0036] 2. Outlet extraction pipe; 3. Outlet extraction branch pipe; 4. Branch regulating valve; 5. Branch flow meter; 6. Main extraction pipe; 7. Main regulating valve; 8. Main flow meter;

[0037] 9. Outlet suction ejector; 901. Receiving port; 902. Oblique square to round joint; 903. Conveying pipe; 904. Inlet; 905. Throat; 906. Ejector outlet;

[0038] 10 First connecting pipe; 11 Discharge port air ejector; 12 Second connecting pipe; 13 Air extraction device; 14 Hopper; 15 Hopper discharge valve; 16 Dust collector; 17 Total flow meter. Detailed Implementation

[0039] To better understand the technical content of this invention, the following embodiments are provided for detailed explanation.

[0040] In the description of this invention, it should be understood that the terms "upper", "lower", "front", "rear", "left", "right", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0041] Please see Figures 1-4 As shown, in the first specific embodiment of the present invention, the device for improving the efficiency of a cyclone separator through dual-channel air extraction includes a cyclone separator 1, an outlet air extraction pipe 2, an outlet air extraction branch pipe 3, a branch regulating valve 4, a branch flow meter 5, a main air extraction pipe 6, a main regulating valve 7, a main flow meter 8, an outlet air extraction ejector 9, a first connecting pipe 10, a discharge port air extraction ejector 11, a second connecting pipe 12, an air extraction device 13, a hopper 14, a hopper discharge valve 15, a dust collector 16, and a total flow meter 17, wherein:

[0042] The cyclone separator 1 includes a cyclone inlet 101, a cylinder 102, a cylinder end cap 103, a cone 104, an intermediate ash hopper 105, a discharge port 106, a cyclone outlet 107, an inner outlet pipe 108, an outer outlet pipe 109, and a pipe end cap 110. The cylinder 102, the cone 104, and the intermediate ash hopper 105 are all vertically arranged and coaxially aligned. The diameter of the upper end of the cone 104 is larger than the diameter of the lower end. The discharge port 106 is located in the lower end of the intermediate ash hopper 105, and the lower end of the cone 104 is located on the upper end of the intermediate ash hopper 105. The lower end of the cylinder 102 is located on the upper end of the cone 104, and the cylinder end cap 103 is located on the upper end of the cylinder 102. The cyclone inlet 101 and the upper part of the cylinder 102 are connected. The outlet inner tube 108 and the outlet outer tube 109 are both vertically and coaxially arranged in an 80° volute-type tangential configuration. The outlet outer tube 109 is vertically inserted into the cylindrical end cap 103 and coaxially arranged with the cylindrical body 102. The upper end of the outlet outer tube 109 protrudes upward from the cylindrical end cap 103. The pipe end cap 110 is located on the upper end of the outlet outer tube 109, and the lower end of the outlet outer tube 109 is located in the cylindrical body 102. The outlet inner tube 108 is vertically inserted into the pipe end cap 110, and the upper end of the outlet inner tube 108 protrudes upward from the pipe end cap 110. The cyclone outlet 107 is located on the upper end of the outlet inner tube 108, and the lower end of the outlet inner tube 108 protrudes downward from the lower end of the outlet outer tube 109 and is located in the cylindrical body 102.

[0043] The outlet outer pipe 109 is connected to the outlet exhaust branch pipe 3 through the outlet exhaust pipe 2. The branch regulating valve 4 and the branch flow meter 5 are both installed in the outlet exhaust branch pipe 3. The main exhaust pipe 6 and the outlet exhaust branch pipe 3 are both connected to the first connecting pipe 10 through the outlet exhaust ejector 9. The main regulating valve 7 and the main flow meter 8 are both installed in the main exhaust pipe 6. The first connecting pipe 10 and the discharge port 106 are both connected to the second connecting pipe 12 through the discharge port exhaust ejector 11. The second connecting pipe 12 is connected to the top of the silo 14 through the exhaust device 13. The silo discharge valve 15 is installed in the bottom of the silo 14. The top of the silo 14 is connected to the total flow meter 17 through the dust collector 16.

[0044] The ratio of the diameter D1 of the inner outlet pipe 108 to the diameter D0 of the cylinder 102, and the relationship between the diameter D2 of the outer outlet pipe 109 and the diameter D1 of the inner outlet pipe 108, can be determined as needed. Preferably, the ratio of the diameter D1 of the inner outlet pipe 108 to the diameter D0 of the cylinder 102, D1 / D0, is D1 / D0 = 0.35 to 0.60, and the relationship between the diameter D2 of the outer outlet pipe 109 and the diameter D1 of the inner outlet pipe 108 is D2-D1 = 25 mm to 60 mm. In the first specific embodiment of the present invention, the ratio of the diameter D1 of the inner outlet pipe 108 to the diameter D0 of the cylinder 102, D1 / D0, is D1 / D0 = 0.35, and the relationship between the diameter D2 of the outer outlet pipe 109 and the diameter D1 of the inner outlet pipe 108 is D2-D1 = 25 mm.

[0045] The ratio of the depth h1 of the outer outlet pipe 109 inserted into the cylinder 102 to the depth h0 of the inner outlet pipe 108 inserted into the cylinder 102 can be determined as needed. Preferably, the ratio h1 / h0 is 0.65 to 0.90. In the first specific embodiment of the present invention, the ratio h1 / h0 is 0.65.

[0046] The outlet suction ejector 9 and the discharge port suction ejector 11 can have any suitable configuration; please refer to [link / reference]. Figure 4As shown, in the first specific embodiment of the present invention, both the outlet suction ejector 9 and the discharge port suction ejector 11 include a receiving port 901, an oblique square connecting circle 902, a conveying pipe 903, an inlet 904, a throat 905, and an ejection outlet 906. The conveying pipe 903 and the throat 905 are both arranged along the left-right direction. The throat 905 is thicker at the left end and thinner at the right end, and is located inside the left end of the conveying pipe 903. The conveying pipe 903 is located between the inlet 904 and the ejection outlet 906 and connects the inlet 904 and the ejection outlet 906 respectively. The oblique square connecting circle 902 is inclined downwards and to the right along the left-right direction. The lower end of the oblique square connecting circle 902 is inclined downwards and to the right. The inclined square circumference 902 is inserted into the middle of the conveying pipe 903 in an inclined direction. The receiving port 901 is located on the upper end of the inclined square circumference 902. The main exhaust pipe 6 and the outlet exhaust branch pipe 3 are respectively connected to the inlet 904 and the receiving port 901 of the outlet exhaust ejector 9. The ejection outlet 906 of the outlet exhaust ejector 9 is connected to the first connecting pipe 10. The first connecting pipe 10 and the discharge port 106 are respectively connected to the inlet 904 and the receiving port 901 of the discharge port exhaust ejector 11. The ejection outlet 906 of the discharge port exhaust ejector 11 is connected to the second connecting pipe 12.

[0047] The ratio of the diameter d1 of the right end of the throat tube 905 to the diameter d0 of the delivery tube 903 can be determined as needed. More preferably, the ratio d1 / d0 is 0.20 to 0.45. In the first specific embodiment of the present invention, the ratio d1 / d0 is 0.20.

[0048] The branch regulating valve 4 and the branch flow meter 5 are used to adjust the outlet air extraction volume drawn from the outlet extraction pipe 2. The volume percentage of the air intake volume of the cyclone inlet 101 relative to the outlet air extraction volume can be determined as needed. Preferably, the outlet air extraction volume is 0.6% to 1.3% of the air intake volume of the cyclone inlet 101, which provides better cyclone performance. In the first specific embodiment of the present invention, the outlet air extraction volume is 0.6% of the air intake volume of the cyclone inlet 101.

[0049] The branch regulating valve and the branch flow meter are used to regulate the outlet air extraction volume drawn from the outlet extraction pipe. The main regulating valve and the main flow meter are used to regulate the main air extraction volume drawn from the main extraction pipe. The total flow meter is used to regulate the total air extraction volume drawn by the extraction device. The discharge port air extraction volume = the total air extraction volume - the outlet air extraction volume - the main air extraction volume. The volume percentage of the cyclone inlet 101's air intake volume that the discharge port air extraction volume is can be determined as needed. Preferably, the discharge port air extraction volume is 1.5% to 6.2% of the cyclone inlet 101's air intake volume, which provides better cyclone performance. In the first specific embodiment of the present invention, the discharge port air extraction volume is 1.5% of the cyclone inlet 101's air intake volume.

[0050] The branch flow meter 5, the main flow meter 8, and the total flow meter 17 can be any suitable flow meter. In the first specific embodiment of the present invention, the branch flow meter 5 is an orifice plate flow meter, and the main flow meter 8 and the total flow meter 17 are both rotor flow meters.

[0051] The exhaust device 13 can be any suitable exhaust device. In the first specific embodiment of the present invention, the exhaust device 13 is an induced draft fan.

[0052] The dust collector 16 can be any suitable dust collector. In the first specific embodiment of the present invention, the dust collector 16 is a bag filter dust collector.

[0053] The working principle of this invention is:

[0054] Gas containing solid dust particles enters the cylinder 102 tangentially through the cyclone inlet 101, causing the airflow to rotate. The airflow rotates from top to bottom along the cylinder wall of the cylinder 102 (i.e., external cyclone). When it reaches the bottom of the cone 104, the airflow gradually changes to rotating upward along the central axis of the cyclone (i.e., internal cyclone). The purified gas is finally discharged from the cyclone outlet 107 through the outlet inner pipe 108. The solid dust particles in the gas are thrown towards the cylinder wall of the cylinder 102 under the action of centrifugal force. Most of the solid dust particles fall into the intermediate ash hopper 105 along the cylinder wall of the cylinder 102 through the cone 104 under the action of gravity and the airflow. These solid dust particles are finally discharged through the discharge port 106.

[0055] Air is drawn in by the extraction device 13. Ambient air enters the outlet extraction ejector 9 through the main extraction pipe 6. Gas inside the cylinder is drawn through the annular gap between the inner outlet pipe 108 and the outer outlet pipe 109 to the outlet extraction pipe 2, and then enters the outlet extraction ejector 9 through the outlet extraction branch pipe 3. External air and gas inside the cylinder enter the discharge port extraction ejector 11 through the first connecting pipe 10. Gas inside the intermediate ash hopper enters the discharge port extraction ejector 11 through the discharge port. The external air, gas inside the cylinder, and gas inside the intermediate ash hopper are combined to form a single extraction device. The gas inside the hopper enters the silo 14 through the second connecting pipe 12 and the exhaust device 13. Thus, the dust collected by the cyclone separator 1 (discharge port dust) and the dust contained in the gas extracted by the outlet exhaust pipe 2 (gas inside the cylinder) are pneumatically transported to the silo 14 by the exhaust device 13. The purified gas after the dust is removed by the dust collector 16 is sent to a centralized venting system for release via the total flow meter 17 (the total flow meter 17 is connected to the centralized venting system pipeline during use). The dust in the silo 14 is discharged through the silo discharge valve 15.

[0056] The device for improving the efficiency of a cyclone separator through two-way air extraction, according to the first specific embodiment of the present invention, was compared and measured with a type B cyclone separator.

[0057] Buell Corporation of the United States is a well-known manufacturer of cyclone separators, whose representative product is the Type B cyclone separator (see "Dust Removal Equipment" in the Complete Book of Chemical Equipment Design, pp. 61-68, Chemical Industry Press, 2002). Referring to the representative test dust proposed at the International Clean Air Conference—talc powder with an average particle size of 18.7 μm—and under the same conditions where both cyclone separators had a diameter of Φ1200 mm, the cyclone performance of the dual-extraction cyclone separator efficiency improvement device of the first embodiment of this invention was compared with that of the Type B cyclone separator.

[0058] Test conditions:

[0059] Gaseous medium: Air (at normal temperature and pressure)

[0060] Gas processing capacity: Q=17600m³ 3 / h (operational state)

[0061] Solid dust: talc powder

[0062] Dust density: ρ = 2720 kg / m³ 3

[0063] Cyclone inlet dust concentration: Cin = 12~15g / m³ 3

[0064] Particle size distribution: volumetric frequency distribution (measured by MALVERN laser particle size analyzer)

[0065] dp (pm) ＜2 2～5 5～10 10～15 15～20 20～30 30～40 40～50 ＞50 f(%) 0.9 2.4 13.7 23.7 27.5 15.0 9.3 5.6 1.9

[0066] Test results:

[0067] ① Comparison of separation efficiency under various cyclone inlet velocities. Please refer to the measurement results. Figure 5 As shown, by Figure 5 It can be seen that, under the same cyclone inlet gas velocity, the device for improving the efficiency of the cyclone separator with two-way air extraction in the first specific embodiment of the present invention has a significantly higher separation efficiency of 3.8 to 4.7% than that of the type B cyclone separator.

[0068] ② Comparison of pressure drop under various cyclone inlet velocities. Please refer to the measurement results. Figure 6 As shown, by Figure 6 It can be seen that, under the same cyclone inlet gas velocity, the device for improving the efficiency of the cyclone separator with two-way air extraction in the first specific embodiment of the present invention can significantly reduce the pressure drop by 13.3 to 27.9% compared with the type B cyclone separator.

[0069] In the second embodiment of the present invention, unlike the first embodiment, the ratio of the diameter D1 of the inner outlet pipe 108 to the diameter D0 of the cylinder 102 is D1 / D0 = 0.50; the relationship between the diameter D2 of the outer outlet pipe 109 and the diameter D1 of the inner outlet pipe 108 is D2-D1 = 60 mm; the ratio of the depth h1 of the outer outlet pipe 109 inserted into the cylinder 102 to the depth h0 of the inner outlet pipe 108 inserted into the cylinder 102 is h1 / h0 = 0.90; the ratio of the diameter d1 of the right end of the throat pipe 905 to the diameter d0 of the conveying pipe 903 is d1 / d0 = 0.30; the outlet suction volume is 1.3% of the air intake volume of the cyclone inlet 101; and the discharge port suction volume is 3% of the air intake volume of the cyclone inlet 101.

[0070] The device for improving the efficiency of a cyclone separator through two-way air extraction according to the second embodiment of the present invention was compared with a type B cyclone separator. The measurement results were similar to those of the device for improving the efficiency of a cyclone separator through two-way air extraction according to the first embodiment of the present invention and a type B cyclone separator, and will not be repeated here.

[0071] In the third embodiment of the present invention, unlike the first embodiment, the ratio of the diameter D1 of the inner outlet pipe 108 to the diameter D0 of the cylinder 102 is D1 / D0 = 0.60; the relationship between the diameter D2 of the outer outlet pipe 109 and the diameter D1 of the inner outlet pipe 108 is D2-D1 = 40 mm; the ratio of the depth h1 of the outer outlet pipe 109 inserted into the cylinder 102 to the depth h0 of the inner outlet pipe 108 inserted into the cylinder 102 is h1 / h0 = 0.75; the ratio of the diameter d1 of the right end of the throat pipe 905 to the diameter d0 of the conveying pipe 903 is d1 / d0 = 0.45; the outlet suction volume is 1.0% of the air intake volume of the cyclone inlet 101; and the discharge port suction volume is 6.2% of the air intake volume of the cyclone inlet 101.

[0072] The device for improving the efficiency of a cyclone separator through two-way air extraction according to the third embodiment of the present invention was compared with the B-type cyclone separator. The measurement results were similar to those of the device for improving the efficiency of a cyclone separator through two-way air extraction according to the first embodiment of the present invention and the B-type cyclone separator, and will not be repeated here.

[0073] In addition to the main swirling flow (i.e., the outer and inner swirling flows), various secondary eddies exist inside the cyclone separator. These secondary eddies have a significant impact on the cyclone separation efficiency. To eliminate these secondary eddies, the dual-channel air extraction device of this invention, which improves the efficiency of the cyclone separator, adopts the above-mentioned structure in its design, thereby greatly improving the performance of the cyclone separator.

[0074] This invention uses an air extraction device to create two air extraction points: a cyclone outlet and a cyclone discharge port. Compared with the prior art, the main advantages of this invention are:

[0075] 1) Exhaust gas extraction at the cyclone outlet can significantly suppress the secondary vortex present in the head region of the cyclone.

[0076] In addition to the main swirling flow (including the inner and outer swirling flows), secondary vortices are prevalent inside the cyclone separator. These vortices consist of axial velocity νz and radial velocity νr. The secondary vortices cause severe "back-mixing" of solid particles inside the cyclone separator, and they have a significant impact on the performance of the cyclone separator, especially on its separation efficiency. The two main types of secondary vortices present in the cyclone head region are: (1) longitudinal circulation in the annular space; and (2) short-circuit flow at the lower end of the outlet pipe. The cyclone outlet exhaust of this invention is composed of a stepped inner outlet pipe and an outer outlet pipe nested together, forming an annular gap between them. The lower end of this annular gap is located at the location of the longitudinal circulation in the annular space and the short-circuit flow at the lower end of the outlet pipe. The dust particles entrained by these two secondary vortices are directly discharged outside the cyclone separator due to the negative pressure generated by the exhaust. Considering that excessive extraction at the cyclone head region would affect the main vortex flow (including the inner and outer vortex flows), a branch flow meter and a branch regulating valve were installed on the cyclone outlet extraction pipe. Tests have shown that when the cyclone outlet extraction volume is controlled at 0.6% to 1.3% of the cyclone inlet volume, the cyclone separation effect is the highest, that is, the suppression effect on the secondary vortices at the two points of "longitudinal circulation in the annular space" and "short-circuit flow at the lower end of the outlet pipe" is the best.

[0077] 2) The air extraction at the cyclone discharge port can significantly reduce the secondary eddies existing in the cylinder and cone areas of the cyclone separator.

[0078] Similarly, in addition to the main swirling flow (including the inner and outer swirling flows), secondary vortices are prevalent inside the cyclone separator. These secondary vortices cause severe "back-mixing" of solid particles inside the cyclone separator, significantly impacting separation efficiency. The two main types of secondary vortices present in the cylinder and cone regions of the cyclone separator are: (1) local vortices in the outer swirling flow; and (2) bottom entrainment. In this invention, the cyclone discharge port is evacuated by a discharge port ejector. Driven by the evacuation device, the discharge port ejector extracts a certain amount of gas from the cylinder and cone of the cyclone separator. The dust particles entrained by the secondary vortices "local vortices in the outer swirling flow" and "bottom entrainment" are directly carried out of the cyclone separator due to the negative pressure generated by the evacuation. At the same time, the negative pressure generated by the evacuation further reduces the deviation of the rotation center of the airflow inside the cyclone from the geometric center of the equipment and the phenomenon of vortex core formation. The efficiency of the cyclone separator, especially the separation efficiency for fine particles, is greatly improved. Considering that excessive extraction of air from the cylinder and cone areas of the cyclone separator would affect the main cyclone (including the inner and outer cyclones), a main regulating valve and a main flow meter were installed on the main extraction pipe. A total flow meter was installed downstream of the extraction device to control the extraction volume at the cyclone discharge port. Tests have shown that the cyclone separation effect is best when the extraction volume at the cyclone discharge port is controlled at 1.5% to 6.2% of the volume of the cyclone inlet air volume, that is, the effect of reducing the secondary vortices at the two locations of "local vortices in the outer cyclone" and "bottom entrainment" is the best.

[0079] 3) The air extraction significantly reduces the possibility of discharge port blockage and improves the stability of cyclone operation.

[0080] The ejector at the discharge port is installed at the discharge port. Due to the contraction of the throat inside the ejector to form a high-speed jet, a strong negative pressure zone will be formed at the discharge port according to the Bernoulli equation principle. Therefore, it has a strong suction effect on the dust at the discharge port, which accelerates the discharge of dust at the discharge port, avoids dust clogging the discharge port, and greatly improves the stability of the cyclone operation.

[0081] 4) Air extraction allows the cyclone to maintain high separation efficiency even at lower cyclone inlet air velocities, significantly reducing internal wear of the cyclone and also resulting in relatively low operating resistance.

[0082] Large cyclone separators (e.g., those with a diameter greater than 4000mm) are often designed with high cyclone inlet velocities to achieve high separation efficiency. Common examples include cyclone inlet velocities Vin = 25–30 m / s, or even higher. Since cyclone operating resistance is proportional to the square of the cyclone inlet velocity, this translates to even higher cyclone operating resistance. Furthermore, since internal cyclone wear is proportional to the fourth power of the cyclone inlet velocity, this indicates severe cyclone wear, significantly reducing the cyclone's lifespan. However, the dual-channel extraction device of this invention, which improves cyclone separator efficiency, allows large cyclone separators to achieve high separation efficiency even at lower cyclone inlet velocities, such as Vin = 14–16 m / s. This device not only reduces cyclone operating resistance but also alleviates internal cyclone wear, significantly extending the cyclone's lifespan.

[0083] Therefore, by employing this invention, two extraction points are formed through the exhaust device: the cyclone outlet and the cyclone discharge port. Exhaust at the cyclone outlet significantly suppresses the longitudinal circulation in the annular space of the cyclone head region and the short-circuit flow at the lower end of the exhaust pipe. Exhaust at the cyclone discharge port greatly weakens local vortices and bottom entrainment in the inner and outer layers of the cyclone within the cylinder and cone regions, thereby reducing the deviation of the internal airflow rotation center from the geometric center of the equipment and weakening the vortex nucleus phenomenon. Simultaneously, it significantly reduces the possibility of discharge port blockage and improves the stability of cyclone operation. The efficiency of the cyclone separator, especially its separation efficiency for fine particles, is greatly improved. Comparative tests show that under the same conditions, the separation efficiency of the cyclone separator can be increased by 3.8–4.7%, a very significant effect; at the same time, the operating resistance is reduced by 13.3–27.9%. This invention is applicable to the improvement of efficiency and other performance aspects of common cylindrical-conical cyclone separators, and is particularly beneficial for improving the separation efficiency and reducing the operating resistance of large cyclone separators. This invention has a simple structure and reasonable design, making it suitable for large-scale industrial application.

[0084] In summary, the dual-channel air extraction device of the present invention for improving the efficiency of a cyclone separator can suppress and weaken secondary eddies, improve cyclone separation efficiency, reduce operating resistance, and is ingeniously designed, simple in structure, easy to manufacture, and low in manufacturing cost, making it suitable for large-scale promotion and application.

[0085] Therefore, it is evident that the objective of this invention has been fully and effectively achieved. The function and structural principles of this invention have been demonstrated and explained in the embodiments. Any modifications can be made to the implementation methods without departing from these principles. Therefore, this invention includes all modified embodiments based on the spirit and scope of the claims.

Claims

1. A device for improving the efficiency of a cyclone separator through dual-channel air extraction, comprising a cyclone separator, the cyclone separator including a cyclone inlet, a cylindrical body, a cylindrical end cap, a cone, an intermediate ash hopper, a discharge port, and a cyclone outlet, wherein the cylindrical body, the cone, and the intermediate ash hopper are all vertically arranged and coaxially arranged, the diameter of the upper end of the cone is larger than the diameter of the lower end of the cone, the discharge port is located in the lower end of the intermediate ash hopper, the lower end of the cone is located on the upper end of the intermediate ash hopper, the lower end of the cylindrical body is located on the upper end of the cone, the cylindrical end cap is located on the upper end of the cylindrical body, and the cyclone inlet is tangent to the upper part of the cylindrical body at a 180° volute configuration, characterized in that... The dual-channel exhaust system for improving the efficiency of the cyclone separator also includes an outlet exhaust pipe, an outlet exhaust branch pipe, a branch regulating valve, a branch flow meter, a main exhaust pipe, a main regulating valve, a main flow meter, an outlet exhaust ejector, a first connecting pipe, a discharge port exhaust ejector, a second connecting pipe, an exhaust device, a hopper, a hopper discharge valve, a dust collector, and a total flow meter, wherein: The cyclone separator further includes an inner outlet pipe, an outer outlet pipe, and a pipe end cap. Both the inner outlet pipe and the outer outlet pipe are vertically arranged and coaxially. The outer outlet pipe is vertically inserted into the pipe end cap and coaxially arranged with the cylinder body. The upper end of the outer outlet pipe protrudes upward from the pipe end cap. The pipe end cap is located on the upper end of the outer outlet pipe. The lower end of the outer outlet pipe is located in the cylinder body. The inner outlet pipe is vertically inserted into the pipe end cap. The upper end of the inner outlet pipe protrudes upward from the pipe end cap. The cyclone outlet is located on the upper end of the inner outlet pipe. The lower end of the inner outlet pipe protrudes downward from the lower end of the outer outlet pipe and is located in the cylinder body. The outlet outer pipe is connected to the outlet exhaust branch pipe through the outlet exhaust pipe. The branch regulating valve and the branch flow meter are both installed in the outlet exhaust branch pipe. The main exhaust pipe and the outlet exhaust branch pipe are both connected to the first connecting pipe through the outlet exhaust ejector pipe. The main regulating valve and the main flow meter are both installed in the main exhaust pipe. The first connecting pipe and the discharge port are both connected to the second connecting pipe through the discharge port exhaust ejector pipe. The second connecting pipe is connected to the top of the silo through the exhaust device pipe. The silo discharge valve is installed in the bottom of the silo. The top of the silo is connected to the total flow meter through the dust collector pipe.

2. The device for improving the efficiency of a cyclone separator through dual-channel air extraction as described in claim 1, characterized in that, The ratio of the diameter D1 of the inner outlet tube to the diameter D0 of the cylinder is D1 / D0 = 0.35 to 0.60, and the relationship between the diameter D2 of the outer outlet tube and the diameter D1 of the inner outlet tube is D2-D1 = 25mm to 60mm.

3. The device for improving the efficiency of a cyclone separator through dual-channel air extraction as described in claim 1, characterized in that, The ratio of the depth h1 into which the outer outlet pipe is inserted into the cylinder to the depth h0 into which the inner outlet pipe is inserted into the cylinder is h1 / h0 = 0.65 to 0.

90.

4. The device for improving the efficiency of a cyclone separator through dual-channel air extraction as described in claim 1, characterized in that, Both the outlet suction ejector and the discharge port suction ejector include a receiving port, an oblique square joint, a conveying pipe, an inlet, a throat, and an ejection outlet. The conveying pipe and the throat are both arranged along the left-right direction. The throat is wider at the left end and narrower at the right end, and is located inside the left end of the conveying pipe. The conveying pipe is situated between the inlet and the ejection outlet and connects to both. The oblique square joint is inclined downwards and to the right from left to right, and its lower end is inserted along the inclination direction of the oblique square joint. The receiving port is located at the upper end of the inclined square-shaped circumference in the middle of the conveying pipe. The main exhaust pipe and the outlet exhaust branch pipe are respectively connected to the inlet and the receiving port of the outlet exhaust ejector. The ejector outlet pipe of the outlet exhaust ejector is connected to the first connecting pipe. The first connecting pipe and the discharge port are respectively connected to the inlet and the receiving port of the discharge port exhaust ejector. The ejector outlet pipe of the discharge port exhaust ejector is connected to the second connecting pipe.

5. The device for improving the efficiency of a cyclone separator through dual-channel air extraction as described in claim 4, characterized in that, The ratio of the diameter d1 of the right end of the throat tube to the diameter d0 of the delivery tube is d1 / d0 = 0.20 to 0.

45.

6. The device for improving the efficiency of a cyclone separator through dual-channel air extraction as described in claim 1, characterized in that, The branch regulating valve and the branch flow meter are used to regulate the outlet air extraction volume drawn from the outlet extraction pipe, wherein the outlet air extraction volume is 0.6% to 1.3% of the volume of the inlet air of the cyclone inlet.

7. The device for improving the efficiency of a cyclone separator through dual-channel air extraction as described in claim 1, characterized in that, The branch regulating valve and the branch flow meter are used to regulate the outlet air volume drawn from the outlet exhaust pipe. The main regulating valve and the main flow meter are used to regulate the main air volume drawn from the main exhaust pipe. The total flow meter is used to regulate the total air volume drawn by the exhaust device. The discharge port air volume = the total air volume - the outlet air volume - the main air volume. The discharge port air volume is 1.5% to 6.2% of the volume of the cyclone inlet air volume.

8. The device for improving the efficiency of a cyclone separator through dual-channel air extraction as described in claim 1, characterized in that, The branch flow meter is an orifice plate flow meter, and the main flow meter and the total flow meter are both rotor flow meters.

9. The device for improving the efficiency of a cyclone separator through dual-channel air extraction as described in claim 1, characterized in that, The air extraction device is an induced draft fan.

10. The device for improving the efficiency of a cyclone separator through dual-channel air extraction as described in claim 1, characterized in that, The dust collector is a bag filter.

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