Rotary dispensing device, system and control method

Abstract

The application provides a rotary discharging device, system and control method, and belongs to the technical field of industrial kiln fuel supply and process control; the rotary discharging device comprises a rotor, a driving unit and a shell, the shell comprises an upper feeding port, a lower discharging port and a rotary bin matched with the rotor; arc-shaped gas supply cavities are respectively arranged in the wall thickness of the shell on both sides of the rotary bin, and guide injection holes are arranged in at least two rows along the circumference of the rotor to form an injection hole array; the injection hole array is configured to make the airflow be obliquely injected in a direction forming an acute angle with the circular side plate, and cooperate with the rotary motion of the rotor to form a pneumatic sealing barrier between the rotor and the side wall of the rotary bin. The application utilizes the two-stage anti-blocking mechanism of the oblique injection hole, i.e. first impact energy consumption and then airflow blowing away, so that the injection hole can still be long-term unblocked under the harsh working conditions of high particle size difference and high fiber content, and the defects of local blocking and overall failure of the existing slit gas curtain are overcome, and the maintenance frequency and downtime loss are reduced.

Description

Technical Field

[0001] This invention belongs to the field of industrial kiln fuel supply and process control technology, specifically relating to a rotary feeding device, system and control method. Background Technology

[0002] Industrial kiln systems (such as cement preheating furnaces and rotary kilns) typically operate under high negative pressure under the forced suction of induced draft fans to prevent the escape of high-temperature flue gas and dust and to control airflow direction. The rotary airlock feeding device, acting as the crucial link between the fuel bin and the kiln, serves the dual function of continuously and quantitatively feeding solid fuel into the furnace while simultaneously preventing the negative pressure from drawing in cold air from the outside. If a large amount of cold air is drawn in, it will lower the furnace temperature, disrupt the combustion balance, and the amount of oxygen brought in by the cold air is uncontrollable, altering the overall combustion atmosphere within the furnace.

[0003] Traditional rotary airlock feeders are primarily designed for materials with good flowability and uniform particle size, such as pulverized coal. The mechanical gap between the rotor and the casing can be controlled within a very small range, and good airlock can be achieved by relying on physical obstruction. However, when applied to alternative fuels (RDF / SRF, biomass-derived fuels, sludge-derived fuels, etc.), the airlock fails due to the complex composition, large particle size differences, high moisture content, and significant fluctuations in apparent density of the alternative fuels.

[0004] Existing structures and control methods, designed to prevent long fibers and blockages in the rotor compartment, force an increase in the circumferential mechanical clearance between the rotor and the casing when processing alternative fuels. This leads to a sharp reduction in the efficiency of the mechanical airlock, and an uncontrollable increase in air leakage under high negative pressure inside the furnace. To address the air leakage caused by the increased mechanical clearance, existing technologies have introduced continuous spray slit air curtain seals for reinforcement. However, while the air curtain structure design can theoretically form a continuous air film, the slit width is usually designed to be extremely small to ensure the "rigidity" of the air curtain. This makes it extremely difficult and costly to manufacture on large rotating casings. Most importantly, under harsh operating conditions with high particle size differences and high fluctuations, the slits are easily blocked by debris carried by the airflow. Local blockage creates pressure seal gaps, making long-term reliable operation difficult. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a rotary feeding device, system and control method to address the shortcomings of existing continuous spray seam air curtain seals which are prone to clogging.

[0006] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows: A rotary feeding device includes a rotor, a drive unit, and a housing. The housing includes an upper feed port, a lower discharge port, and a rotary chamber that matches the rotor. The power output end of the drive unit passes through the housing and is sealed and driven by the rotor. The rotor includes two parallel and coaxially arranged circular side plates, and a plurality of blades evenly distributed between the two circular side plates along the circumferential direction; two adjacent blades, the two circular side plates, and the rotor shaft together form a plurality of material receiving cavities; The rotating chamber has arc-shaped air supply chambers on both sides inside the wall of the shell. The side of the arc-shaped air supply chamber closest to the rotating chamber has a guide nozzle that communicates with the rotating chamber, and the side away from the rotating chamber is connected to an external air source. The guide nozzles are arranged in at least two rows along the circumference of the rotor to form a nozzle array; the axes of each row of guide nozzles are in the same plane and parallel to each other, and form the same acute angle with the plane where the same adjacent circular side plate is located, and the axes of two adjacent rows of guide nozzles are respectively oriented towards the planes where two different circular side plates are located. The nozzle array is configured to eject airflow obliquely at an acute angle to the circular side plate, thereby forming a pneumatic sealing barrier between the rotor and the side wall of the rotary chamber in conjunction with the rotor's own rotational motion.

[0007] Furthermore, the nozzle array is arranged in multiple staggered rows in the circumferential direction; the diameter of the guide nozzle is greater than the net spacing between adjacent guide nozzles; and the depth of the guide nozzle along the wall thickness direction of the housing is greater than its diameter.

[0008] Furthermore, in the radial section of the rotor, the axes of all the guide nozzles are deflected toward the side where the upper feed port is located, and the axis of each guide nozzle forms an elevation angle of 10° to 30° with the horizontal plane perpendicular to the rotor axis; in the axial section of the rotor, the axis of the guide nozzle forms an acute angle of 15° to 45° with the plane where the circular side plate adjacent to the guide nozzle is located.

[0009] Optionally, the planes in which the axes of the guide nozzles in each row lie are parallel to each other.

[0010] Optionally, the plane in which the axes of each row of guide nozzles lie is fan-shaped, and the plane in which the axes of each row of guide nozzles lie intersects in the same axial region within the rotary chamber.

[0011] Optionally, the planes on which the axes of two adjacent rows of guide nozzles are located are set at an angle, and the planes on which the axes of two adjacent rows of guide nozzles are located intersect at different axial positions within the rotary chamber, so as to form multiple axial intersection areas distributed circumferentially.

[0012] Furthermore, the arc-shaped air supply chamber is divided into a first air supply section, a second air supply section, and a third air supply section arranged sequentially along the axial direction of the rotor; the first air supply section and the third air supply section are located at opposite ends of the arc-shaped air supply chamber along the axial direction, and the second air supply section is located at the middle of the arc-shaped air supply chamber along the axial direction; the injection pressure of the first air supply section and the third air supply section is the same and greater than the injection pressure of the second air supply section; the first air supply section, the second air supply section, and the third air supply section are independently connected to an external air source through their respective corresponding air delivery channels.

[0013] The rotary feeding system includes an external air source, a pressure detection unit, a feed flow detection unit, a control unit, and the aforementioned rotary feeding device; The pressure detection unit includes pressure sensors respectively installed on the material inlet channel and the material outlet channel, and is configured to acquire upstream pressure signal P1 and downstream pressure signal P2. The feeding flow detection unit, including a flow meter, is located at the inlet of the material inlet channel or the rotary feeding device and is configured to collect the feeding flow signal F in real time. The control unit is connected to the rotary feeding device, external air source, pressure detection unit, and feed flow detection unit via signals. The control unit is configured to adjust the rotor speed of the rotary feeding device and the gas flow rate of the external air source into the arc-shaped air supply chamber based on the information collected by the pressure detection unit and the feed flow rate detection unit.

[0014] The rotary feeding control method implemented using the above-mentioned rotary feeding system performs the following steps: S1. Acquire the upstream pressure signal synchronously collected within the preset control cycle. Downstream pressure signals 2 and feed flow signal The sampling sequence; S2. Calculate the pressure difference based on the collected signals. and the feed flow rate signal within the current control cycle Standard deviation And calculate the air leakage risk index according to the following formula. ;

[0015] In the formula, This is the pressure difference weighting coefficient. This is the feed fluctuation weighting coefficient. , All are positive real numbers, calibrated according to system specifications; S3, the aforementioned air leakage risk indicators With preset risk threshold Comparison: when At the same time, maintain the current gas flow rate and rotor speed constant; when At that time, the gas flow rate delivered from the external gas source to the arc-shaped gas supply chamber is increased by a preset ratio; if the gas flow rate has reached the preset upper limit, Still greater than If necessary, the rotor speed is reduced to maintain feeding continuity.

[0016] Furthermore, the arc-shaped air supply chamber is divided into a first air supply section, a second air supply section, and a third air supply section arranged sequentially along the axial direction of the rotor; in step S3, the preset ratio is the ratio of the average injection pressure of the first air supply section and the third air supply section to the injection pressure of the second air supply section.

[0017] Compared with existing technologies, this invention utilizes a two-stage anti-clogging mechanism of first impact energy dissipation and then airflow blowing away oblique nozzles, enabling the nozzles to remain unobstructed for a long time under harsh working conditions with high particle size differences and high fiber content. This fundamentally overcomes the defect of existing continuous slit air curtains where partial blockage leads to overall failure, and significantly reduces maintenance frequency and downtime losses.

[0018] In addition, the high-pressure gas ejected from the oblique nozzles fills the cavities near the side plates at both ends of the rotor, and impacts the inner surface of the side plates to form a high-pressure air cushion, which suppresses the local low-pressure air leakage area induced by flow separation, and fundamentally solves the hidden problem of air leakage in the cavity caused by the shielding of the side plates in the existing technology.

[0019] By employing various nozzle array configurations, such as parallel layout, fan-shaped layout, and multi-row multi-intersection layout, along with a three-stage non-uniform air supply strategy, the distribution of the sealing pressure field can be flexibly optimized according to rotor specifications and operating conditions, achieving on-demand sealing and precise sealing, while ensuring sealing performance and saving air consumption.

[0020] Also based on pressure difference and feed fluctuations The calculated comprehensive leakage risk index R integrates two dimensions: driving force and channel unobstructedness. It employs a graded adjustment strategy of first increasing the isolation high-pressure gas flow and then decreasing the rotational speed, along with a proportional incremental strategy. This enables the system to adaptively adjust under different leakage risk levels, balancing sealing effect, feeding continuity, and operating energy consumption. Most importantly, the leakage rate is transformed from passively unknown to actively controllable, ensuring that the actual leakage rate is controlled within a preset threshold. This significantly reduces the disturbance of leakage to the downstream combustion balance under fluctuating alternative fuel conditions. Attached Figure Description

[0021] The present invention will now be described in further detail with reference to the accompanying drawings.

[0022] Figure 1 : Schematic diagram of existing air leakage channels; Figure 2 : A schematic diagram of the structure of Embodiment 1 of the present invention; Figure 3 : A three-dimensional cross-sectional structural diagram of Embodiment 1 of the present invention; Figure 4 : A cross-sectional structural diagram of the arc-shaped air supply cavity in Embodiment 1 of the present invention; Figure 5 : A second schematic diagram of the cross-sectional structure of the arc-shaped air supply cavity in Embodiment 1 of the present invention; Figure 6 The present invention presents a deflection-acute-angle jet (arrows simulate jet) in the radial-axial plane. Figure 7 The present invention presents an upwardly deflected jet in the circumferential-axial plane (arrows simulate the jet; examples of multiple axially intersecting regions distributed circumferentially). Figure 8 : A schematic diagram of the system structure of Embodiment 2 of the present invention; Among them, rotor 1, circular side plate 11, blade 12, material receiving cavity 13, arc-shaped air supply cavity 14, first air supply section 141, second air supply section 142, third air supply section 143, guide nozzle 15, nozzle array 16, drive unit 2, housing 3, upper feed port 31, lower discharge port 32, rotary chamber 33. Rotary feeding device 100, external air source 200, pressure detection unit 300, feeding flow detection unit 400, control unit 500. Detailed Implementation

[0023] To better understand the present invention, the following embodiments further illustrate the content of the invention, but the scope of protection of the present invention is not limited to the following embodiments. Numerous specific details are set forth in the following description to provide a more thorough understanding of the invention. However, it will be apparent to those skilled in the art that the present invention can be practiced without one or more of these details.

[0024] In the description of this invention, it should be understood that the orientation or positional relationship indicated by directional terms such as "front, back, up, down, left, right", "horizontal, vertical, horizontal" and "top, bottom" is generally based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing this invention and simplifying the description. Unless otherwise stated, these directional terms 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, and therefore should not be construed as a limitation on the scope of protection of this invention; the directional terms "inner" and "outer" refer to the inner and outer contours relative to the outline of each component itself.

[0025] Furthermore, it should be noted that the use of terms such as "first" and "second" to define components is merely for the purpose of distinguishing the corresponding components. Unless otherwise stated, the above terms have no special meaning and therefore should not be construed as limiting the scope of protection of this invention.

[0026] Regarding rotary feeding devices, operators have also discovered through long-term research and development practice that the existing rotary feeding device casing, for the purpose of preventing blockage, covers the gap between the outer surface of the circular side plates at both ends of the rotor and the rotary chamber (see reference). Figure 1 The design of the section within the red box is not, as is commonly believed in the field, a purely beneficial structure. Rather, it is one of the hidden root causes of air leakage under negative pressure conditions. Firstly, the shielding effect causes material to accumulate only in the middle of the rotor's material receiving cavity. The upper corners at both ends of the material receiving cavity form empty cavities. These cavities, rotating with the rotor, create air leakage channels (see reference). Figure 1 (The red arrow indicates the part); Secondly, the continuous spray slit type air curtain commonly used in this field, because the airflow direction is parallel to the side plates at both ends of the rotor, not only cannot seal the cavity, but also induces laminar flow separation on the inner surface of the circular side plate, forming a local low-pressure air leakage area. As the rotor rotates, it draws in outside air and cannot effectively curb the air leakage phenomenon.

[0027] Therefore, this application provides a rotary feeding device, as shown in Embodiment 1, see reference. Figure 2-7 ; The rotary feeding device 100 includes a rotor 1, a drive unit 2, and a housing 3. The housing 3 includes an upper feed port 31, a lower discharge port 32, and a rotary chamber 33 that matches the rotor 1. The power output end of the drive unit 2 passes through the housing 3 and is sealed and driven by the rotor 1. The rotor 1 includes two parallel and coaxially arranged circular side plates 11, and a plurality of blades 12 evenly distributed between the two circular side plates along the circumferential direction; two adjacent blades 12, two circular side plates 11 and the rotor central shaft together form a plurality of material receiving cavities 13. Arc-shaped air supply chambers 14 are respectively formed on both sides of the rotating chamber 3 inside the wall thickness of the shell 3. The side of the arc-shaped air supply chamber 14 near the rotating chamber 33 is provided with a guide nozzle 15 communicating with the rotating chamber 33, and the side away from the rotating chamber 33 is connected to an external air source 200. The high-pressure gas provided by the external air source 200 is distributed through the arc-shaped air supply chamber 14 and then directionally injected into the rotating chamber 33 through the guide nozzle 15.

[0028] The medium of the external gas source 200 can be compressed air, nitrogen, argon, or other inert gases. It should be noted that when only compressed air is used, the sealing principle does not rely on the chemical inertness of the sealing medium itself to isolate oxygen, but rather on the directional momentum barrier formed by the high-speed airflow to block pressure transmission and turbulent exchange between upstream and downstream. Although compressed air contains oxygen, compared to the natural and disordered infiltration of ambient air, using compressed air transforms the fluctuation of oxygen content in the system from a random variable into a predictable steady-state value, and the input compressed air temperature is expected, facilitating subsequent compensation and adjustment by the combustion control system. When other inert gases are used as the medium of the external gas source 200, they further combine the chemical inertness of the medium itself with the isolation of oxygen, forming a sealing barrier, compared to compressed air.

[0029] The guide nozzles 15 are arranged in at least two rows along the circumference of the rotor 1 to form a nozzle array 16. The axes of each row of guide nozzles 15 are in the same plane and parallel to each other, and form the same acute angle with the plane of the adjacent circular side plate 11. The axes of two adjacent rows of guide nozzles 15 are respectively oriented towards the planes of two different circular side plates 11. That is, the axis of one row of guide nozzles 15 is inclined towards the left circular side plate 11, and the axis of the adjacent other row of guide nozzles 15 is inclined towards the right circular side plate 11. This alternating oblique nozzle layout allows the high-pressure gas flow ejected from the nozzle array 16 to cover the cavity areas near the inner side of the circular side plates 11 at both ends of the rotor 1, so that the ejected high-pressure gas is obliquely directed towards the cavity areas near the side plates at both ends of the rotor 1.

[0030] After the high-pressure gas enters the cavity, it first creates a high-pressure environment, making the pressure inside the cavity higher than that at the upstream feed inlet 31. This forms a pressure barrier at the cavity inlet, preventing outside air from seeping into the cavity from the feed inlet 31 side. Subsequently, the obliquely ejected high-pressure gas flow continues to move forward, impacting the inner surface of the circular side plate 11, forming a stable high-pressure air cushion near the inner surface of the circular side plate 11. The presence of this high-pressure air cushion alters the flow field distribution near the inner surface of the circular side plate 11, effectively suppressing the flow separation phenomenon that would normally occur on the inner surface of the circular side plate 11 under the action of parallel airflow, and preventing the formation of local low-pressure zones. The gas within the high-pressure air cushion itself flows into the kiln interior in a small, controlled manner under the influence of the pressure difference, but effectively prevents the uncontrolled infiltration of outside air.

[0031] The nozzle array 16 is configured to eject airflow obliquely at an acute angle to the circular side plate 11, forming a pneumatic sealing barrier between the rotor 1 and the side wall of the rotary chamber 33 in conjunction with the rotational motion of the rotor 1. This pneumatic sealing barrier is not static but dynamically changes with the rotation of the rotor 1. When a material receiving cavity 13 rotates into the area covered by the nozzle array 16, the obliquely ejected high-pressure airflow forms a high-pressure air film in the gap between the material receiving cavity 13, the material inside it, and the side wall of the rotary chamber 33, effectively blocking the airflow channel between the upper inlet 31 and the lower outlet 32. When the material receiving cavity 13 rotates away from the area covered by the nozzle array, the next material receiving cavity 13 immediately enters, and the pneumatic sealing barrier moves accordingly, thereby achieving a continuous and uninterrupted airlock effect.

[0032] The nozzle array 16 is arranged in multiple staggered rows in the circumferential direction, so that the jet coverage areas of adjacent rows of guide nozzles 15 overlap, avoiding sealing blind spots in the circumferential direction. The diameter of the guide nozzles 15 is larger than the net spacing between adjacent guide nozzles 15, so as to form a continuous jet curtain, rather than discrete jet beams. In some specific embodiments, the diameter of the guide nozzles 15 can be 3mm-5mm.

[0033] The depth of the guide nozzle 15 along the wall thickness direction of the housing 3 is greater than its diameter. On the one hand, the deeper nozzle channel has a guiding and rectifying effect on the jet, so that the turbulent airflow entering the guide nozzle 15 from the arc-shaped air supply cavity 14 is rectified into a jet with consistent direction and uniform speed within the channel, which improves the rigidity and penetrating power of the jet and forms a stable high-pressure airflow. On the other hand, it increases the difficulty for materials to enter the nozzle, because the materials need to overcome the frictional resistance of the longer channel to be fully embedded, and are blown away by the airflow during the entry process, further reducing the risk of blockage.

[0034] During the operation of the rotary feeding device 100, the upper feed port 31 side is the high-pressure side (close to atmospheric pressure or fuel tank pressure), and the lower discharge port 32 side is the low-pressure side (close to the negative pressure inside the furnace). The main direction of the leakage airflow is from the upper feed port 31 side through the gap between the rotor and the side wall of the rotary chamber 33 to the lower discharge port side. Based on this, in the radial section of the rotor 1, the axes of all the guide nozzles 15 are deflected toward the side where the upper feed port 31 is located, and the axes of each guide nozzle 15 form an elevation angle of 10° to 30° with the horizontal plane perpendicular to the axis of the rotor 1; the deflection of the axes of the guide nozzles 15 toward the upper feed port 31 side makes the upward velocity component of the jet airflow opposite to the downward flow direction of the leakage airflow, forming a countercurrent, which further increases the aerodynamic resistance that the leakage airflow needs to overcome and improves the sealing effect.

[0035] Within the axial section of the rotor 1, the axis of the guide nozzle 15 forms an acute angle of 15° to 45° with the plane of the adjacent circular side plate 11. This acute angle determines the angle at which the jet obliquely impacts the inner surface of the circular side plate 11. When the acute angle is less than 15°, the jet is too parallel to the circular side plate 11, resulting in insufficient impact force on the inner surface of the circular side plate 11, making it difficult to form an effective high-pressure air cushion. Furthermore, the jet may still induce flow separation on the inner surface of the circular side plate 11. When the acute angle is greater than 45°, the jet is too perpendicular to the circular side plate 11. Although the impact force is large, the axial range of the material receiving cavity 13 covered by the jet is reduced, and the jet may reflect and impact the material receiving cavity 13 in the opposite direction, interfering with normal material feeding. Experiments have verified that when the acute angle is within the range of 15° to 45°, the jet can form a stable high-pressure air cushion, cover a sufficient axial range, and does not interfere with material feeding.

[0036] It is important to note that the elevation angle in the radial section and the acute angle in the axial section are two independent angular parameters, controlling the deflection of the jet in different directions. The elevation angle controls the jet deflection in the circumferential-axial plane, causing the jet to point obliquely upwards towards the side plate cavity; the acute angle controls the jet deflection in the radial-axial plane, causing the jet to impact the inner surface of the circular side plate 11 obliquely. The synergistic effect of the two angles causes the jet to form a spatial oblique spray posture, simultaneously achieving the triple functions of preventing blockage, covering the cavity, and forming an air cushion.

[0037] Optionally, the planes in which the axes of the guide nozzles 15 lie are parallel to each other, so that each exhaust stream is injected directly into the rotary chamber 33 at an oblique angle. This parallel layout is simple to manufacture, has high consistency in jet direction, and uniform distribution of the sealing pressure field. It is suitable for situations where the rotor 1 has a small diameter, the material receiving cavity 13 has a short axial dimension, and the material has good flowability. In such cases, the parallel jets are sufficient to cover the entire axial range of the side plate cavity.

[0038] Optionally, the plane containing the axes of each row of guide nozzles 15 is fan-shaped, and the planes containing the axes of each row of guide nozzles 15 converge in the same axial region within the rotary chamber 33. That is, all jet surfaces converge at the same axial position within the rotary chamber 33, forming a focused jet convergence zone. By converging multiple rows of jets into the same axial region, a local high-pressure zone is formed in this region. The pressure in this high-pressure zone is much higher than that formed by a single row of jets, which can more effectively block air leakage channels. The fan-shaped jets undergo mutual entrainment and energy exchange in the convergence zone. The turbulence intensity in the convergence zone is significantly higher than that of a single row of jets. The high shear rate of the turbulence helps to break up any possible local low-pressure eddies, further suppressing flow separation, making it suitable for applications requiring relatively high-speed rotary feeding.

[0039] Optionally, the planes on which the axes of two adjacent rows of guide nozzles 15 lie are arranged at an angle, and the planes on which the axes of two adjacent rows of guide nozzles 15 lie intersect at different axial positions within the rotary chamber 33, forming multiple axial intersection zones distributed circumferentially. The arrangement of multiple axial intersection zones can improve the system's fault tolerance. When the jet flow of a certain row of guide nozzles 15 weakens due to the instantaneous impact of a large piece of material, the jet flow of adjacent rows of guide nozzles 15 can still maintain the sealing pressure of the intersection zone, preventing overall seal failure due to an abnormality in a single row of guide nozzles 15. This is suitable for applications where the material particle size varies greatly and the flowability is relatively weak.

[0040] As mentioned earlier, the cavities formed near the circular side plates 11 at both ends of the rotor 1 due to insufficient material accumulation are the main channels for air leakage, while the middle of the rotor has a lower risk of air leakage due to the full accumulation of material. Therefore, the arc-shaped air supply chamber 14 is further divided along the axial direction of the rotor 1 into a first air supply section 141, a second air supply section 142, and a third air supply section 143 arranged in sequence. The first air supply section 141 and the third air supply section 143 located at both ends of the axial direction provide higher injection pressure to form a sufficient high-pressure air cushion in the edge cavity of the material receiving chamber 13 to seal the air leakage channels at both ends. The second air supply section 142 located in the middle of the axial direction can provide a lower injection pressure because the presence of material in the middle itself has a certain mechanical air-locking effect, and the pneumatic seal only needs to play an auxiliary role in reinforcement.

[0041] The injection pressures of the first air supply section 141 and the third air supply section 143 are the same and greater than the injection pressure of the second air supply section 142. The first air supply section 141, the second air supply section 142, and the third air supply section 143 are independently connected to the external air source 200 through their respective corresponding air supply channels. At this time, the external air source 200 is configured with at least two independent air sources, one of which simultaneously supplies air to the two second air supply sections 142 located on both sides of the rotary chamber 33, and the other simultaneously supplies air to the two first air supply sections 141 and the two third air supply sections 143 located on both sides of the rotary chamber 33.

[0042] Therefore, while ensuring the overall sealing effect, the low-pressure air supply in the middle can save air consumption, reduce operating energy consumption, and also reduce the disturbance to the material in the material receiving cavity 13 in the middle of rotor 1. This avoids the material being blown away by excessive airflow and further concentrates resources to seal the weakest leakage channel for the high-pressure air supply at both ends, thus improving the pertinence and effectiveness of the seal.

[0043] This embodiment utilizes a two-stage anti-clogging mechanism of first impacting and then blowing away airflow in the oblique nozzle 15, which enables the nozzle to remain unobstructed for a long time under harsh working conditions with high particle size difference and high fiber content. This fundamentally overcomes the defect of existing continuous slit air curtains where partial blockage leads to overall failure, and significantly reduces maintenance frequency and downtime losses.

[0044] In addition, the high-pressure gas ejected from the oblique nozzle 15 fills the cavity near the inner surface of the circular side plates 11 at both ends of the rotor 1, forming a high-pressure air cushion. This suppresses the local low-pressure air leakage area induced by flow separation, fundamentally addressing the hidden problem of air leakage in the cavity caused by the shielding of the side plates in the existing technology, and significantly reducing the amount of air leakage entering the kiln. Although the gas in the high-pressure air cushion itself flows into the kiln in a small amount and in a controlled manner under the action of pressure difference, it effectively prevents the uncontrolled infiltration of outside air.

[0045] By employing various nozzle array configurations, such as parallel layout, fan-shaped layout, and multi-row multi-intersection layout, along with a three-stage non-uniform air supply strategy, the distribution of the sealing pressure field can be flexibly optimized according to the rotor specifications and operating conditions, thus saving air consumption while ensuring sealing performance.

[0046] Example 2, see Figure 8 , The rotary feeding system includes an external air source 200, a pressure detection unit 300, a feed flow detection unit 400, a control unit 500, and the aforementioned rotary feeding device 100. An external air source 200 provides high-pressure gas to the pneumatic seal of the rotary feeding device 100. The medium can be compressed air, nitrogen, argon, or other inert gases. The outlet pressure and flow rate of the external air source 200 are adjustable. The external air source 200 is connected to each air supply section of the arc-shaped air supply chamber 14 through independent air supply channels to achieve segmented independent air supply.

[0047] The pressure detection unit 300 includes pressure sensors respectively installed on the inlet channel and the outlet channel, configured to acquire upstream pressure signal P1 and downstream pressure signal P2; the upstream pressure sensor is installed on the inlet channel (such as the feed pipe of the hopper) upstream of the upper feed port, reflecting the gas pressure on the inlet side, which is usually close to or slightly lower than atmospheric pressure; the downstream pressure sensor is installed on the outlet channel (such as near the kiln feed port) downstream of the lower outlet, reflecting the negative pressure in the furnace.

[0048] The feeding flow detection unit 400 includes a flow meter, the type of which is selected according to the material characteristics: for powdery or granular materials, an impulse flow meter or a loss-in-weight feeder can be used; for blocky or fibrous alternative fuels, a belt scale, a weighing feeder, or other metering devices can be used. It is installed at the inlet of the material inlet channel or the rotary feeding device and configured to collect the feeding flow signal F in real time. The control unit 500 is connected to the rotary feeding device 100, the external air source 200, the pressure detection unit 300, and the feeding flow detection unit 400 by signal. The control unit 500 is configured to adjust the rotor speed of the rotary feeding device 100 and the gas flow rate input to the arc-shaped air supply chamber 14 by the external air source 200 based on the information collected by the pressure detection unit 300 and the feeding flow rate detection unit 400. Specifically, the control unit 500 has a built-in leakage risk index calculation model and control strategy. Based on the real-time collected P1, P2, and F signals, it calculates the leakage risk index R, and automatically adjusts the rotor speed and gas flow rate based on the comparison result of R with a preset threshold, thereby achieving closed-loop adaptive control.

[0049] Example 3, see Figure 8 , The rotary feeding control method implemented using the above-mentioned rotary feeding system performs the following steps. Acquire upstream pressure signals synchronously within a preset control cycle. Downstream pressure signals 2 and feed flow signal The sampling sequence is used. The control period is typically 1 to 3 seconds, determined based on the system's dynamic response characteristics and control accuracy requirements. A control period that is too short will result in excessively frequent control actions, affecting system stability; a control period that is too long will fail to respond promptly to changes in operating conditions. The purpose of synchronous data acquisition is to ensure... , 2. The three signals correspond to the operating conditions at the same time, avoiding the distortion of the air leakage risk index calculation due to signal timing misalignment.

[0050] Based on the collected signals, the pressure difference is calculated. and the feed flow rate signal within the current control cycle Standard deviation And calculate the air leakage risk index according to the following formula. ;

[0051] In the formula, This is the pressure difference weighting coefficient. This is the feed fluctuation weighting coefficient. , All values ​​are positive real numbers, calibrated according to system specifications (such as rated differential pressure and rated feed rate). Therefore, the pressure and flow rate are automatically normalized to the same order of magnitude.

[0052] pressure difference This reflects the driving pressure difference between the upstream and downstream sides. The larger the value, the stronger the driving force for drawing outside air into the furnace, and the higher the risk of air leakage. (Feed rate standard deviation) This reflects the degree of fluctuation in material feeding. The larger the value, the more uneven the material filling within the rotor, the higher the exposure of the edge cavities of the material receiving cavity 13, the more unobstructed the air leakage channels, and the higher the risk of air leakage. Therefore, [the following text is incomplete and requires further context: "will"] and The weighted summation of the comprehensive index R can reflect the leakage risk of both the driving force and the channel unobstructedness, making it more comprehensive and accurate than a single index.

[0053] The air leakage risk indicators With preset risk threshold Comparison: when This indicates that the risk of air leakage under the current operating conditions is within an acceptable range. Maintaining the current gas flow rate and rotor speed unchanged avoids unnecessary adjustments and reduces system energy consumption.

[0054] when If the air leakage risk exceeds the acceptable range under the current operating conditions, adjustment measures need to be taken to reduce the air leakage risk; the adjustment strategy adopts a graded strategy of first increasing the gas flow rate and then reducing the rotor speed.

[0055] The gas flow rate supplied by the external gas source 200 to the arc-shaped gas supply chamber 14 is increased synchronously with the ratio of the injection pressure of the first gas supply section 141 and the third gas supply section 143 to the injection pressure of the second gas supply section 142; that is, the risk of air leakage is reduced primarily by enhancing the pneumatic seal. Increasing the gas flow rate is the preferred measure because the pneumatic seal has a fast response speed and does not affect the feeding rate. It can quickly suppress air leakage without interrupting production. Moreover, by maintaining the method of synchronously increasing the gas flow rate with the pressure ratio, the distribution of the sealing pressure field remains stable and will not disrupt the optimized distribution of high pressure at both ends and low pressure in the middle due to the increase in flow rate.

[0056] If the gas flow rate has reached the preset upper limit. Still greater than If the rotor speed is reduced, the feeding continuity will be maintained. With the reduced speed, the residence time of material in each material receiving cavity 13 is extended, resulting in more complete material filling, reduced exposure of the edge cavities of the material receiving cavity 13, and narrowing of the air leakage channel. It should be noted that reducing the rotor speed will reduce the feeding amount; therefore, this measure, as a second line of defense, is only activated when pneumatic seal adjustment is insufficient to control the risk of air leakage.

[0057] This embodiment is based on pressure difference. and feed fluctuations Calculated comprehensive air leakage risk index This system integrates two dimensions: driving force and channel unobstructed flow. It employs a graded adjustment strategy of first increasing airflow and then decreasing speed, along with a proportional incremental strategy. This allows the system to adaptively adjust under different leakage risk levels, balancing sealing performance, feeding continuity, and operating energy consumption. Most importantly, the leakage rate is transformed from passively unknown to actively controllable, ensuring that the actual leakage rate is controlled within a preset threshold. This significantly reduces the disturbance of leakage to the downstream combustion balance under fluctuating alternative fuel conditions.

[0058] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Any other modifications or equivalent substitutions made by those skilled in the art to the technical solutions of the present invention, as long as they do not depart from the spirit and scope of the technical solutions of the present invention, should be covered within the scope of the claims of the present invention.

Claims

1. A rotary feeding device, comprising a rotor, a drive unit, and a housing, wherein the housing includes an upper feed inlet, a lower discharge outlet, and a rotary chamber matching the rotor; the power output end of the drive unit passes through the housing and is sealed and driven by the rotor; characterized in that: The rotor includes two parallel and coaxially arranged circular side plates, and a plurality of blades evenly distributed between the two circular side plates along the circumferential direction; two adjacent blades, the two circular side plates, and the rotor shaft together form a plurality of material receiving cavities; The rotating chamber has arc-shaped air supply chambers on both sides inside the wall of the shell. The side of the arc-shaped air supply chamber closest to the rotating chamber has a guide nozzle that communicates with the rotating chamber, and the side away from the rotating chamber is connected to an external air source. The guide nozzles are arranged in at least two rows along the circumference of the rotor to form a nozzle array; the axes of each row of guide nozzles are in the same plane and parallel to each other, and form the same acute angle with the plane where the same adjacent circular side plate is located, and the axes of two adjacent rows of guide nozzles are respectively oriented towards the planes where two different circular side plates are located. The nozzle array is configured to eject airflow obliquely at an acute angle to the circular side plate, thereby forming a pneumatic sealing barrier between the rotor and the side wall of the rotary chamber in conjunction with the rotor's own rotational motion.

2. The rotary feeding device according to claim 1, characterized in that: The nozzle array is arranged in multiple staggered rows in the circumferential direction; the diameter of the guide nozzle is greater than the net spacing between adjacent guide nozzles; the depth of the guide nozzle along the wall thickness direction of the housing is greater than its diameter.

3. The rotary feeding device according to claim 1, characterized in that: In the radial section of the rotor, the axes of all the guide nozzles are deflected toward the side where the upper feed port is located, and the axis of each guide nozzle forms an elevation angle of 10° to 30° with the horizontal plane perpendicular to the rotor axis; in the axial section of the rotor, the axis of the guide nozzle forms an acute angle of 15° to 45° with the plane where the circular side plate adjacent to the guide nozzle is located.

4. The rotary feeding device according to claim 3, characterized in that: The planes in which the axes of the guide nozzles in each row lie are parallel to each other.

5. The rotary feeding device according to claim 3, characterized in that: The plane containing the axes of each row of guide nozzles is fan-shaped, and the planes containing the axes of each row of guide nozzles intersect in the same axial region within the rotary chamber.

6. The rotary feeding device according to claim 3, characterized in that: The guide nozzles are arranged in at least four rows along the circumference of the rotor to form a nozzle array; the planes on which the axes of two adjacent rows of guide nozzles are located are set at an angle, and the planes on which the axes of two adjacent rows of guide nozzles are located intersect at different axial positions within the rotary chamber to form multiple axial intersection areas distributed along the circumference.

7. The rotary feeding device according to claim 1, characterized in that: The arc-shaped air supply chamber is divided into a first air supply section, a second air supply section, and a third air supply section arranged sequentially along the axial direction of the rotor; the first air supply section and the third air supply section are located at opposite ends of the arc-shaped air supply chamber along the axial direction, and the second air supply section is located at the middle of the arc-shaped air supply chamber along the axial direction; the injection pressure of the first air supply section and the third air supply section is the same and greater than the injection pressure of the second air supply section; the first air supply section, the second air supply section, and the third air supply section are independently connected to an external air source through their respective corresponding air delivery channels.

8. A rotary feeding system, characterized in that: Includes an external air source, a pressure detection unit, a feed flow detection unit, a control unit, and a rotary feeding device as described in any one of claims 1-7; The pressure detection unit includes pressure sensors respectively installed on the material inlet channel and the material outlet channel, and is configured to acquire upstream pressure signal P1 and downstream pressure signal P2. The feeding flow detection unit, including a flow meter, is located at the inlet of the material inlet channel or the rotary feeding device and is configured to collect the feeding flow signal F in real time. The control unit is connected to the rotary feeding device, external air source, pressure detection unit, and feed flow detection unit via signals. The control unit is configured to adjust the rotor speed of the rotary feeding device and the gas flow rate of the external air source into the arc-shaped air supply chamber based on the information collected by the pressure detection unit and the feed flow rate detection unit.

9. A rotary feeding control method, characterized in that: The rotary feeding system described in claim 8 is used to achieve this, specifically by performing the following steps: S1. Acquire the upstream pressure signal synchronously collected within the preset control cycle. Downstream pressure signals 2 and feed flow signal The sampling sequence; S2. Based on the collected signals, calculate the upstream and downstream pressure difference for each sampling. Obtain the average pressure difference between upstream and downstream during the current control cycle. Obtain the feed flow rate signal within the current control cycle. Standard deviation And calculate the air leakage risk index according to the following formula. ; In the formula, This is the pressure difference weighting coefficient. This is the feed fluctuation weighting coefficient. , All are positive real numbers, calibrated according to system specifications; S3, the aforementioned air leakage risk indicators With preset risk threshold Comparison: when At the same time, maintain the current gas flow rate and rotor speed constant; when At the same time, the gas flow rate delivered from the external gas source to the arc-shaped gas supply chamber is increased according to a preset ratio; If the gas flow rate has reached the preset upper limit. Still greater than If necessary, the rotor speed is reduced to maintain feeding continuity.

10. The rotary feeding control method according to claim 9, characterized in that: The arc-shaped air supply chamber is divided into a first air supply section, a second air supply section, and a third air supply section arranged sequentially along the axial direction of the rotor; in step S3, the preset ratio is the ratio of the average injection pressure of the first air supply section and the third air supply section to the injection pressure of the second air supply section.

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