Cyclone dynamic roasting device for dust collection and short process treatment technology

Abstract

This invention relates to the field of metallurgical technology, and in particular to a dynamic cyclone roasting device and short-process treatment technology for dust collector ash. The device includes a main cyclone roasting cylinder with an air curtain pressure compensation chamber, air curtain nozzles, a variable geometry guide vane assembly, and a differential pressure sensing matrix. Closed-loop feedback control is constructed using a PLC. The process dynamically adjusts the air curtain intensity, injection angle, and speed based on real-time differential pressure sensing, combined with a high-pressure pulse cleaning and output self-balancing mechanism, to achieve anti-coking on the wall surface, enhanced particle back-mixing, and continuous stable operation. This invention provides a dynamic cyclone roasting device and short-process treatment technology for dust collector ash, aiming to solve the problems of easy material adhesion, flow field instability, and uneven reaction of high-viscosity dust collector ash during high-temperature cyclone roasting.

Description

Technical Field

[0001] This invention relates to the field of metallurgical technology, and in particular to a dynamic cyclone roasting device for dust collection and a short-process treatment technology. Background Technology

[0002] In the fields of metallurgy and resource recycling, dust containing valuable components such as lead, zinc, and alkali metals is a typical complex secondary resource, and its efficient and clean treatment has become a key link in promoting green metallurgy and the development of a circular economy. These materials typically possess characteristics such as high specific surface area, wide particle size distribution, strong thermoviscosity, and enrichment of volatile components. During high-temperature heat treatment, they are prone to melting, agglomeration, and wall adhesion, leading to poor operational stability, high energy consumption, and low recovery rates in traditional thermal equipment. To address these challenges, swirl dynamic roasting technology, due to its excellent gas-solid heat and mass transfer performance, high reaction rate under short residence time, and compact process flow, has been widely explored in recent years for the removal of impurities and metal enrichment in dust. This technology uses a high-speed rotating airflow to suspend or near-suspend the material, theoretically enabling continuous and short-process resource recovery while enhancing pyrolysis, oxidation, or reduction reactions. However, when faced with highly viscous dust with drastic fluctuations in physical properties, the existing cyclone calcination system reveals deep-seated structural defects at the level of chemical-physical coupling behavior, which seriously restricts its industrial application.

[0003] Specifically, existing technical solutions mostly follow the static or semi-dynamic flow field architecture designed for structurally stable, low-viscosity minerals (such as molybdenum concentrate or iron ore powder). For example, patent CN108149006B proposes a self-heating swirl roasting device that recovers reaction heat through a jacketed heat exchange structure to preheat combustion air. Although this improves energy utilization efficiency, the furnace body lacks any active protection mechanism against high-temperature dust adhesion. The reason for this is that the design logic of this solution is based on the assumption that material particles remain rigid and do not easily soften or melt at high temperatures. However, the alkali metal chlorides, sulfates, and low-melting-point oxides (such as the PbO-ZnO eutectic system) abundant in the dust collector exhibit significant surface fluidity and thermal viscosity in the 500–800℃ range. Once they come into contact with the furnace wall at a temperature higher than their softening point, a dense coke layer is rapidly formed. The reciprocating feeding process is not only not linearly accelerated—the initial feeding itself worsens wall heat dissipation, generating high-temperature points that melt more subsequently arriving particles—but it also causes dynamic distortion in the flow channel geometry, disrupting the axisymmetry of the swirling field, resulting in airflow eccentricity or even collapse, leading to system blockage or shutdown for ash removal. Another corresponding approach, such as the circulating fluidized bed-cyclone preheating combined system disclosed in application number CN101386908B, employs multi-stage separation to improve thermal efficiency, but it still uses fixed fluidization parameters and passive separation, failing to perceive and influence instantaneous flow field disturbances within the furnace. Fluctuations in dust and ash feed, material moisture content, and negative pressure conditions cause the variance of the material's residence time distribution in the swirling space to deviate from the design value. Short-circuited fine particles are discharged before participating in the reaction, while coarse particles have excessively long residence times and sinter, making it difficult to guarantee overall calcination uniformity.

[0004] Furthermore, the fundamental reason for the aforementioned technical deficiencies is that existing cyclone roasting facilities fail to couple the interfacial chemical behavior of the high-temperature multiphase reaction system with macroscopic fluid dynamics control in the design of high-temperature multiphase reaction facilities. Specifically, the collected dust is not simply an inert roasting carrier; its surface chemical properties dynamically change with the temperature gradient: in the low-temperature zone, physically adsorbed moisture and water of crystallization are eliminated; in the medium-temperature zone, alkali metal salts decompose and migrate; and in the high-temperature zone, a low-melting-point eutectic phase appears and achieves wetting and spreading. These chemical changes directly determine the interfacial energy, adhesion work, and shear strength between the particles and the wall. Existing facilities treat the wall as a simple boundary, passively resisting charring through the thermal stability of refractory materials, rather than addressing the issue from the source of reaction kinetics to reduce adhesion. Traditional air curtain protection, if using a constant air supply, not only wastes energy under low loads but also, during high-concentration feeding, fails to effectively isolate the impact of high-density particle flow on the wall due to insufficient airflow. It is a simple mechanical isolation that cannot cope with the dynamic changes in demand caused by the variable properties of the collected dust. Therefore, how to construct an intelligent response mechanism that can sense changes in the flow field and material state inside the furnace in real time and dynamically adjust the wall protection strength and particle movement trajectory accordingly has become the core of breaking through the bottleneck of high-viscosity secondary resource swirl roasting technology.

[0005] In summary, existing cyclone or fluidized bed roasting technologies generally suffer from systemic defects when processing high-viscosity dust, including passive anti-coking, unadjustable flow field, uncontrollable reaction path, and maintenance dependence on downtime. The fundamental problem lies in the failure to deeply couple high-temperature interfacial chemical behavior, particle dynamics, and flow field control. Therefore, developing a cyclone dynamic roasting device and its supporting processing technology that possesses self-sensing and self-adaptive capabilities in its structure and achieves short-process and high-stability operation has become a key challenge and an urgent technical problem for those skilled in the art. Summary of the Invention

[0006] The purpose of this invention is to solve or at least alleviate the problems of severe coking, flow field distortion, and uneven reaction caused by the mismatch between interfacial chemical behavior and flow field during high-temperature heat treatment of metallurgical dust with high viscosity and drastic fluctuations in physical properties. This invention provides a cyclone dynamic roasting device for metallurgical dust and a short-process treatment technology.

[0007] To achieve the above objectives, the present invention provides the following technical solution: a dynamic cyclone calcination device for collected dust, comprising:

[0008] The main swirl roasting cylinder has a main air inlet distribution structure at its bottom for forming an upward rotating reference flow field.

[0009] The composite wall sandwich structure is formed by a refractory lining and a metal shell to form an annular air curtain pressure compensation chamber. The air curtain pressure compensation chamber is divided into at least two independent air supply sections along the height of the cylinder. Each independent air supply section is connected to an independent adjustable air source and is equipped with an array of air curtain nozzles.

[0010] The differential pressure sensing matrix includes a center pressure acquisition probe located at the geometric center axis of the main swirling roasting cylinder, and a cavity pressure sensor located in each of the independent gas supply sections.

[0011] The variable geometry guide vane assembly is integrated at the inlet or outlet of the air curtain nozzle. It is linked to the synchronous adjustment mechanism through an external drive mechanism to adjust the tangential deflection angle and axial elevation angle of the air curtain spray.

[0012] The logic control system is electrically connected to the differential pressure sensing matrix, the adjustable gas source, and the external drive mechanism. It is used to independently trigger the flow field reconstruction program of the corresponding section according to the degree of deviation of the real-time differential pressure of each independent gas supply section from the reference differential pressure.

[0013] To further realize the present invention, the following technical solutions may be preferred:

[0014] Preferably, the outlet edge of the air curtain nozzle adopts an asymmetrical arc design to induce the airflow to adhere to the refractory lining surface after leaving the nozzle by utilizing the Coanda effect; the synchronous adjustment mechanism is configured to: during the adjustment process, make the outlet axial elevation angle of the air curtain nozzle at different height positions present a differentiated nonlinear gradient distribution.

[0015] The air curtain nozzle has an upper lip and a lower lip, the radius of curvature of the upper lip being greater than that of the lower lip, causing the jetting airflow to deflect toward the refractory lining.

[0016] Preferably, it also includes a pulse cleaning component connected in parallel to the air curtain air supply pipeline. The logic control system is configured to: monitor the back pressure change rate at the discharge end of the device; when the back pressure change rate exceeds a preset safety limit, trigger the pulse cleaning component to perform instantaneous high-pressure injection; and automatically restore the air curtain parameters to a steady-state value after cleaning.

[0017] Preferably, the central pressure acquisition probe extends to the axial position of the main swirl roasting cylinder through a high-temperature pressure-sensing tube; the independent gas supply sections of the air curtain pressure compensation chamber are isolated by a flexible sealing structure to adapt to the thermal expansion differences in different temperature zones.

[0018] Preferably, the adjustment range of the variable geometry guide vane assembly covers the angle between the air curtain injection direction and the tangential direction of the inner wall of the cylinder, and the logic control system adjusts the tangential deflection angle linearly or nonlinearly according to the change in the tangential velocity of the main vortex.

[0019] A short-process technology, implemented based on the above-mentioned apparatus, includes the following steps:

[0020] S1: Baseline establishment: Establish a baseline flow field under no-feed conditions, obtain the initial pressure difference between the air curtain pressure compensation chamber and the central area of ​​the cylinder in each independent air supply section, and use it as the safe operation baseline for each section.

[0021] S2: Zoned adaptive protection. After feeding and operation, the deviation of the measured pressure difference of each section from the safe operation benchmark is monitored in real time. Different pressure difference trigger sensitivity is set for sections at different heights. When the deviation meets the trigger condition of the corresponding section, the logic control system increases the air curtain supply intensity of the section and adjusts the nozzle tangential deflection angle to keep the air curtain jet momentum and the main swirling tangential momentum dynamically matched.

[0022] S3: Path control, which adjusts the spiral rising pitch of material particles by adjusting the axial elevation angle of the nozzle, and ensures that the residence time of the material in the cylinder meets the preset threshold according to the material reaction kinetics requirements.

[0023] S4: Flux self-balancing. By monitoring the output flow fluctuation at the discharge end, when the output flow is continuously lower than the material input, the interception intensity of the air curtain is dynamically weakened to achieve dynamic self-balancing of the system's material flow.

[0024] Preferably, in step S2, the setting logic for the differential pressure trigger sensitivity is as follows: the closer the section is to the material separation zone, the higher its differential pressure trigger sensitivity, in order to cope with the high-frequency disturbance of fine particles; the dynamic matching of the air curtain jet momentum and the main swirling tangential momentum refers to maintaining the air curtain jet speed slightly higher than the main swirling tangential speed.

[0025] Preferably, in step S3, the adjustment of the axial elevation angle adopts a non-linear distribution strategy: a smaller elevation angle is set in the lower region of the cylinder to provide moderate lift, a larger elevation angle is set in the middle reaction region to increase the number of rotations, and a medium elevation angle is set in the upper region to balance the airflow output.

[0026] Preferably, step S3 further includes closed-loop control based on temperature feedback: when the material temperature at the discharge port is detected to be lower than the preset reaction temperature, the axial elevation angle of the air curtain is reduced to forcibly increase the number of rotations of the material in the cylinder.

[0027] Preferably, it also includes an abnormal self-healing step: when the instantaneous fluctuation rate of the system back pressure indicates that primary scaling has occurred, a pulse cleaning program is executed without interrupting the roasting operation, using instantaneous high-energy airflow to peel off the ash accumulated on the inner wall, and the air curtain control parameters are automatically reset after the peeling is completed.

[0028] The beneficial effects of this invention are:

[0029] The device of this invention constructs an integrated "sensing-response" dynamic wall protection mechanism, deeply coupling differential pressure feedback control with air curtain injection logic. This enables real-time intervention and adaptive regulation of particle dynamics within the furnace. By deeply integrating differential pressure sensing, air curtain dynamics, flexible mechanisms, and intelligent control, a high-temperature reaction system with environmental perception, behavior prediction, and autonomous adjustment capabilities is constructed. Real-time control of air curtain injection intensity and morphology via differential pressure feedback forms dynamic wall protection; process-wise, it achieves flow field perception, adaptive air curtain coordination, residence time control, and high-pressure pulse cleaning. Attached Figure Description

[0030] Figure 1 This is a schematic diagram of the overall structure of the dust collection ash cyclone dynamic roasting device of the present invention.

[0031] Figure 2 This is a process flow diagram of the short-process technology of the present invention.

[0032] Figure 3 This is a comparative diagram of the wall deposition evolution of the present invention.

[0033] Figure 4 This is a comparison diagram of the particle residence time distribution of the present invention.

[0034] Figure 5 This is a comparison chart of the system differential pressure stability of the present invention.

[0035] The attached figures are labeled as follows:

[0036] 100. Main swirl roasting cylinder; 101. Porous distribution plate; 102. Inverted cone discharge section; 200. Air curtain pressure compensation chamber; 201. Lower section chamber; 202. Middle section chamber; 203. Upper section chamber; 301. Air curtain nozzle; 302. Variable geometry guide vane assembly; 303. Stepper motor; 400. Air supply system; 401. Variable frequency air supply fan; 402. Quick-opening solenoid valve; 403. Backflush branch; 501. Center pressure acquisition probe; 502. Cavity pressure sensor; 600. Logic control system. Detailed Implementation

[0037] In the description of this invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0038] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0039] Example 1

[0040] This embodiment provides a dynamic cyclone roasting device for collected dust, such as... Figure 1 As shown, the device aims to construct an intelligent thermal reaction system based on aerodynamic principles and multivariable closed-loop control to solve the problems of coking and short-circuiting of high-viscosity metallurgical dust under high-temperature swirling conditions.

[0041] 1. Main swirl roasting cylinder 100 and flow field reference generation system

[0042] The main swirl roasting cylinder 100 is a vertically oriented hollow cylindrical shell with a fully welded structure, serving as the main reaction vessel. An inverted conical discharge section 102 is located at the bottom of the main swirl roasting cylinder 100. The cylinder is made of Q345R low-alloy high-strength pressure vessel steel with a plate thickness of 20mm and a design pressure rating of 0.6MPa to ensure structural safety under high temperature and potential deflagration conditions. The cylinder has a designed inner diameter of 2800mm and a total height of 12.5m, with an effective reaction height (i.e., the main particle residence zone) of 10.5m and a length-to-diameter ratio of approximately 3.75:1. This ratio is beneficial for forming a stable long-axis swirl field.

[0043] Thermal stress relief structure: A ring-shaped reinforcing rib is set every 1.5m along the axial direction of the cylinder on the outer wall of the cylinder. The reinforcing rib is intermittently welded to the cylinder (weld length 100mm, circumferential spacing 200mm) to allow the cylinder to undergo a small amount of radial thermal expansion at 950℃, thereby eliminating thermal stress and preventing weld cracking.

[0044] A porous distribution plate 101 is installed in the bottom air inlet chamber of the cylinder. The porous distribution plate 101 is made of 316L stainless steel and is 25mm thick. To ensure the axisymmetry of the reference swirling flow field and its edge anti-interference capability, the openings of the distribution plate adopt a non-uniform concentric circle array with denser openings on the outside and sparser openings on the inside. Specifically, the opening ratio in the edge region is higher than that in the center region (e.g., 42% at the edge compared to 30% at the center). The purpose of this design is to compensate for the momentum loss of the airflow due to friction at the sidewalls, so that the tangential velocity of the initial swirling flow field is distributed radially without velocity dead zones, thereby improving the axisymmetry and edge anti-interference capability of the reference swirling flow field.

[0045] 2. Three-section, independently controlled air curtain pressure compensation chamber 200

[0046] The composite wall sandwich structure consists of an inner corundum-mullite refractory lining and an outer metal shell. The refractory lining is 150 mm thick and is fired at 1400℃ on the hot side to form a dense, corrosion-resistant layer with an apparent porosity of no more than 14%, a room temperature compressive strength of no less than 80 MPa, and a thermal conductivity of no more than 1.2 W / (m·K), ensuring resistance to alkali metal vapor (K, Na) penetration corrosion at 950℃.

[0047] The annular air curtain pressure compensation chamber 200 is physically separated by two 20mm thick heat-resistant steel (0Cr25Ni20) partitions, dividing it axially into three chambers with distinct functions: Lower chamber 201 (swirl-initiating preheating zone): 3.5m high, mainly responsible for the resuspension of large particles and preheating of cold materials; Middle chamber 202 (constant temperature reaction zone): 4.0m high, with the highest temperature, the most concentrated liquid phase generation, and the greatest chance of coking; Upper chamber 203 (gas-solid separation zone): 3.0m high, mainly to prevent initial material adhesion caused by electrostatic adsorption of fine powder.

[0048] Because the expansion coefficients of the inner lining and the outer shell differ greatly, Ω-shaped 304 stainless steel bellows expansion joints are installed at the joints of each section's partition. The axial compensation of the expansion joints is ±15mm, which ensures that there is no air leakage between sections and that each pressure is independently controlled throughout the entire temperature range, thus forming a thermal expansion compensation system.

[0049] Each section has an independent air inlet flange (DN150) connected to the corresponding variable frequency air supply fan 401 in the air supply system 400. The fan's rated air volume is 12000 m³ / h. 3 / h, total pressure 8000Pa, equipped with an 18.5kW variable frequency motor, can achieve stepless speed regulation from 0-50Hz, thus achieving complete decoupling control of back pressure in each segment.

[0050] 3. Variable geometry nozzle with Coanda effect and flexible flow guiding mechanism

[0051] The entire furnace is equipped with 144 micron-sized air curtain nozzles 301 that are evenly distributed tangentially.

[0052] The nozzle body is made of high-temperature alloy precision lost-wax casting, and the nozzle inner cavity is fluid polished with a surface roughness Ra≤0.2μm to reduce the frictional resistance of the airflow on the wall.

[0053] To achieve a greater film adhesion effect, the nozzle outlet flow channel is not a straight line as is usually designed, but rather an asymmetrical "Coanda Profile". For example, the radius of curvature of the upper lip of the nozzle is greater than that of the lower lip, with the former having a radius of 0.3 mm and the latter 0.1 mm. The nozzle outlet flow channel is inclined towards the lower lip of the nozzle.

[0054] According to the principle of fluid adhesion to walls, after the high-speed airflow is ejected, the flow velocity on the lower lip edge is faster. Due to the greater curvature, the static pressure is lower than that on the upper lip edge. As a result, the airflow naturally deflects along the lower side (i.e., the direction of the inner wall of the cylinder) under the action of pressure difference, so that the nozzle obtains a "wall-attached jet" that is close to the wall. Even if the mechanical spray angle of the nozzle is 0°, the airflow flows close to the wall, thereby eliminating the vortex dead zone below the traditional nozzle.

[0055] Each nozzle inlet is equipped with guide vanes from a variable geometry guide vane assembly 302. The vanes are made of carbon fiber reinforced ceramic matrix composite material, measuring 25mm × 8mm × 1.2mm, and are heat-resistant up to 1600℃. All vane shafts pass through the furnace wall and connect to an external synchronous ring linkage mechanism, driven by a stepper motor 303 via a worm gear reducer. This transmission chain design ensures that the guide vanes can achieve precise synchronous adjustment in the range of 0° to 20°, down to the 0.05° level, and features a self-locking function to prevent the airflow reaction force from altering the angle.

[0056] 4. Self-cleaning differential pressure sensing matrix

[0057] The differential pressure transmitter matrix consists of three sets of high-precision micro differential pressure transmitters, making it particularly suitable for dusty environments. The center pressure acquisition probe 501 adopts a dual protection structure of "corundum ceramic sleeve + nitrogen backflush film". The probe extends horizontally into the geometric center of the furnace, and the probe tip is equipped with a microporous ceramic filter (pore size 5μm) to prevent dust from entering the pressure tapping tube.

[0058] All pressure tapping lines are connected in parallel to a 0.8MPa high-pressure nitrogen backflushing branch 403. The logic control system 600 is set to perform a 3-second pulse backflushing every 4 hours of operation to remove dust accumulation on the filter surface and ensure the long-term accuracy of measurement data.

[0059] The cavity pressure sensor 502 is directly embedded in the compensation cavity of the upper, middle and lower independent air supply sections to provide real-time feedback on the back pressure status of each section.

[0060] Example 2

[0061] This embodiment provides a short-process technology, such as... Figure 2 As shown, this process is based on the concepts of model predictive control and PID cascade control. It uses a PLC to execute the following logic, abandoning simple numerical comparison and instead focusing on the dynamic relationship between physical quantities.

[0062] S1: Baseline Establishment and Hot Parameter Correction

[0063] Cold calibration: With no material fed in, start the main fan to establish a reference vortex field. The PLC collects the static pressure difference between the compensation chamber and the vortex center area in each section, and records it as the cold reference.

[0064] Hot-state logic correction: The system takes into account that as the furnace temperature increases, the gas density decreases and the viscosity increases, the Reynolds number of the fluid decreases, causing the inherent resistance characteristics of the system to drift nonlinearly.

[0065] Corrected Implementation: The PLC collects the furnace temperature in real time and dynamically compensates the cold-state reference based on the ideal gas law and the gas viscosity-temperature change formula. Preferably, the corrected reference pressure difference is positively correlated with the absolute temperature, and its trend approximately satisfies... The corrected reference value is used as the true "safe operating reference value" for each section at the current temperature and written into the PLC, ensuring that the control logic can maintain high accuracy throughout the entire temperature range from normal temperature start-up to 950℃ high temperature operation.

[0066] S2: Zonal Differentiated Sensitivity Control and Momentum Matching

[0067] After feeding, the system enters closed-loop protection mode. The PLC executes PID cascade control logic:

[0068] Outer loop (differential differential pressure response logic): Real-time monitoring of the deviation between the measured differential pressure and the reference. To address the differences in coking mechanisms at different heights, the system is configured with differentiated response sensitivities:

[0069] Upper section (high sensitivity zone): Because fine powder is easily adsorbed by electrostatics to form an initial material layer here, the system is set with an extremely high response weight (high proportional gain). This means that even a small pressure difference fluctuation will trigger a large adjustment of the air curtain; Middle section (standard zone): Set with a medium response weight; Lower section (low sensitivity zone): Set with a low response weight and introduce a strong integral action to allow for moderate particle accumulation to increase heat exchange efficiency and avoid frequent oscillations of the system due to random disturbances from large particles.

[0070] Inner loop (momentum matching logic): The PLC adjusts the spray intensity of the air curtain based on the control quantity output from the differential pressure loop. Its core control objective is to maintain the suppressive relationship between the "air curtain momentum" and the "main swirling tangential momentum".

[0071] The air curtain must possess sufficient kinetic energy to penetrate the centrifugal compression field generated by the main vortex. Therefore, the air curtain's injection velocity needs to constantly follow the tangential velocity variation of the main vortex and maintain a certain overshoot. Preferably, the air curtain injection velocity... Maintain at the tangential velocity of the main swirling flow Between 1.2 and 1.5 times, that is .in, For fluid density, molecules The momentum flux of the air curtain is denoted by , which characterizes the kinetic energy intensity of the air curtain jet. The tangential momentum flux of the main swirling flow reflects the kinetic energy intensity and momentum ratio of the centrifugal field of the main swirling flow. It directly measures the ability of the curtain momentum to suppress the main swirl flow. ≥1.44 ensures that the kinetic energy of the air curtain is sufficient to penetrate the centrifugal compression field formed by the main vortex; if <1, the air curtain cannot break through the swirling flow field, resulting in control failure; >1 provides a dynamic stability margin.

[0072] The synchronous drive stepper motor 303 enables the guide vane tangential angle to be adaptively adjusted according to the intensity of the main swirling flow, ensuring that the airflow cut-in angle is always in the optimal wall-attaching range (5°-15°).

[0073] S3: Path control based on nonlinear elevation angle gradient

[0074] To address the coexistence of "short circuit" and "overburning" issues in short-process manufacturing, the system implements a nonlinear elevation angle control strategy. By adjusting the axial elevation angle of the nozzle, the spiral pitch of the particles is precisely controlled, thereby regulating the residence time.

[0075] The lower nozzle (swirl zone - anti-collapse logic) is set to a positive elevation angle (upward deflection). The airflow provides a moderate upward force to help wet and cold materials quickly pass through the feed inlet dead zone, preventing material from accumulating and collapsing at the bottom.

[0076] The mid-section nozzle (reaction zone - time-increase logic) is set to the maximum elevation angle. Utilizing the principle of vector synthesis, the tangential velocity component of the particles is significantly increased while the axial velocity component is reduced, forcing the particles to rotate at high frequency in this high-temperature core region (e.g., increasing the number of rotations from the traditional 12 to 35), thereby ensuring sufficient reaction time.

[0077] The upper nozzle (separation zone - rectification logic) is set to a medium elevation angle to balance the airflow output and prevent fine particles from escaping due to excessive axial velocity.

[0078] If the infrared thermometer at the discharge port detects that the material temperature is lower than the preset value, it indicates that the reaction is incomplete. The PLC will activate the "delay mode," uniformly reducing the elevation angle of each section to further suppress axial velocity and extend the overall residence time. Preferably, the residence time... With axial velocity Inversely proportional, that is ,in, This refers to the actual effective distance the material moves within the main swirl roasting cylinder 100.

[0079] S4: Flux Self-Balancing and Aerodynamic Screening Logic

[0080] The system is equipped with a continuous weighing sensor at the inverted cone discharge section 102. If the output per unit time is continuously lower than 90% of the feed rate and the system does not report a blockage fault, the PLC determines that "excessive air curtain interception" means that the material has formed a dead cycle of "only in and not out" in the furnace.

[0081] To break the vicious cycle, the PLC automatically reduces the air supply pressure of the intermediate air curtain. This essentially changes the air curtain's "pneumatic screening threshold" for particles; the airflow's ability to capture particles depends on the Stokes number (Stk). Reducing the air curtain velocity increases the critical interception particle size, allowing larger, coarse particles to penetrate the air curtain by inertia and enter the discharge zone, thus restoring the system's mass conservation balance. Preferably, the adjustment target is to make the Stokes number less than 1, allowing coarse particles to escape streamline constraints.

[0082] S5: Abnormal self-healing and high-voltage pulse cleanup

[0083] The PLC calculates the rate of change (first derivative) of the back pressure at the discharge port in real time. When this rate of change exceeds the predetermined safety limit (e.g., 0.5 kPa / s), it is determined that initial scaling is forming, thus achieving early detection.

[0084] Once the precursor is detected, the quick-opening solenoid valve 402 connected to the main gas supply line (with a hysteresis time of less than 50 milliseconds) is triggered, rapidly releasing 0.8MPa high-pressure nitrogen gas from the gas tank. Its pulse wave passes through the nozzle array within 20 milliseconds, generating a shock wave oscillation similar to a pneumatic hammer, which is used to shake off the material adhering to the wall.

[0085] After cleaning lasts for 1.5 to 3 seconds, the PLC automatically restores the PID parameters of the air curtain to their stable state before cleaning, without manual intervention, and the cleaning does not interrupt the main roasting.

[0086] Example 3

[0087] To verify the advancement of the technical solution of the present invention, experiments were conducted on the treatment of complex, highly viscous converter ash containing zinc (21.5%), lead (8.2%), and chlorine (6.5%) using the technical solution of the present invention and the prior art (fixed air curtain), and the following comparative data are provided.

[0088] 1. Comparative explanation of the evolution of wall sedimentation (see...) Figure 3 )

[0089] For existing technology (fixed air curtain), after treating the aforementioned high-viscosity converter ash for 48 hours, a 45 mm thick glaze-coated layer has formed on the surface of the refractory lining in the middle section of the cylinder. This glaze-coated layer further increases thermal resistance, causing the reaction temperature to drop by 30°C. This results in an approximately 18% reduction in the effective flow cross-section. The central negative pressure abnormally rises to -850 Pa, and the swirling flow field becomes essentially unstable.

[0090] After 240 hours of continuous operation under the same conditions, the refractory lining of this invention (adaptive air curtain) remained as smooth as ever, covered only by a layer of loose ash less than 2 mm thick. Microscopic analysis revealed that due to the Coanda effect, a layer of air film was consistently formed, preventing particles from contacting the wall surface to form a eutectic liquid phase.

[0091] 2. Comparison of Particle Residence Time Distribution (RTD) (see [reference]) Figure 4 )

[0092] The RTD curve was measured using the pulse tracer method (fluorescent powder).

[0093] The existing RTD curves are wide and flat with large variance, which indicates a large short circuit (fine powder escapes in 3.5s) and a dead zone (coarse powder is retained).

[0094] After implementing the nonlinear elevation angle control in step S3, the RTD curve of this invention exhibits a narrow Gaussian distribution with a variance of almost 0, closely resembling an ideal plug flow reactor (PFR). The average residence time is extended from 5.4 s to 10.8 s, and there are no short-circuit peaks.

[0095] 3. Comparison of system differential pressure stability (see...) Figure 5 )

[0096] This figure records the system response when the feed rate fluctuates rapidly by ±20%. Existing technology exhibits severe pressure differential curve oscillations (amplitude > ±400 Pa), indicating frequent flow field instability. The pressure differential curve of this invention, after undergoing PID self-adjustment and S4 flux self-balancing logic, is constrained within a safe window of ±50 Pa, demonstrating extremely strong robustness.

[0097] 4. Key Performance Indicator Statistics

[0098] The table below shows the operational data statistics of the embodiments of the present invention and those using a traditional fixed air curtain device when processing the same batch of dust:

[0099] Indicator Item This invention Traditional fixed air curtain Technical Principle Analysis Continuous running time 216 hours 46 hours Differentiated thresholding for specific zones eliminates forcing factors at certain heights. Residual chloride in the product 0.14% 1.25% RTD optimization ensures that all particles reach the reaction time. Coarse particle overheating rate 4.3% 23.1% Flux self-balancing logic avoids local overheating Unit product energy consumption 185 kWh / t 280 kWh / t On-demand gas supply (PID control) avoids energy waste. Average air consumption of the curtain 185 Nm³ / h 285 Nm³ / h Momentum matching logic reduces redundant air supply Fault response time ≤15 seconds >4 hours (shutdown required) Pulse cleaning enables online self-healing Product qualification rate 99.2% 84.5% Results of integrated process control

[0100] In summary, this invention integrates mechanical structure with control logic to construct a calcination system with "sensing-thinking-execution" capabilities. This solution solves the engineering challenges of calcining highly viscous dust without relying on mechanical scrapers, achieving long-term stable operation of the equipment and improved product quality.

[0101] The above are merely preferred embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A dynamic cyclone roasting device for dust collection ash, characterized in that, include: The main swirl roasting cylinder (100) has a main air inlet distribution structure at its bottom for forming an upward rotating reference flow field; The composite wall sandwich structure is formed by a fire-resistant lining and a metal shell to form an annular air curtain pressure compensation chamber (200). The air curtain pressure compensation chamber (200) is divided into at least two independent air supply sections along the height direction of the cylinder. Each independent air supply section is connected to an independent adjustable air source and is equipped with an array of air curtain nozzles (301). The differential pressure sensing matrix includes a center pressure acquisition probe (501) located at the geometric center axis of the main swirling roasting cylinder (100), and a cavity pressure sensor (502) located in each of the independent gas supply sections. The variable geometry guide vane assembly (302) is integrated at the inlet or outlet of the air curtain nozzle (301) and is linked to the synchronous adjustment mechanism through an external drive mechanism to adjust the tangential deflection angle and axial elevation angle of the air curtain spray. The logic control system (600) is electrically connected to the differential pressure sensing matrix, the adjustable gas source and the external drive mechanism, and is used to independently trigger the flow field reconstruction program of the corresponding section according to the degree of deviation of the real-time differential pressure of each independent gas supply section from the reference differential pressure.

2. The dust collection ash cyclone dynamic roasting device according to claim 1, characterized in that, The outlet edge of the air curtain nozzle (301) adopts an asymmetrical arc design to induce the airflow to adhere to the surface of the refractory lining after leaving the nozzle by utilizing the Coanda effect; the synchronous adjustment mechanism is configured to make the outlet axial elevation angle of the air curtain nozzle (301) at different height positions present a differentiated nonlinear gradient distribution during the adjustment process.

3. The dust collection ash cyclone dynamic roasting device according to claim 1, characterized in that, It also includes a pulse cleaning component connected in parallel to the air curtain air supply pipeline. The logic control system (600) is configured to: monitor the back pressure change rate at the discharge end of the device; when the back pressure change rate exceeds the preset safety limit, trigger the pulse cleaning component to perform instantaneous high-pressure injection; and automatically restore the air curtain parameters to the steady-state value after cleaning.

4. The dust collection ash cyclone dynamic roasting device according to claim 1, characterized in that, The central pressure acquisition probe (501) extends to the axial position of the main swirling roasting cylinder (100) through a high-temperature pressure-sensing tube; the independent gas supply sections of the air curtain pressure compensation chamber (200) are isolated by a flexible sealing structure to adapt to the thermal expansion differences in different temperature zones.

5. The dust collection ash cyclone dynamic roasting device according to claim 1, characterized in that, The adjustment range of the variable geometry guide vane assembly (302) covers the angle between the air curtain injection direction and the tangential direction of the inner wall of the cylinder, and the logic control system (600) adjusts the tangential deflection angle linearly or nonlinearly according to the change of the tangential velocity of the main swirling flow.

6. A short-process technology, characterized in that, Based on the apparatus according to any one of claims 1 to 5, the method includes the following steps: S1: Baseline establishment: Establish a baseline flow field under no-feed conditions, obtain the initial pressure difference between the air curtain pressure compensation chamber (200) and the central area of ​​the cylinder in each independent air supply section, and use it as the safe operation baseline for each section. S2: Zoned adaptive protection. After feeding and running, the deviation of the measured pressure difference of each section from the safe operating benchmark is monitored in real time. Different pressure difference trigger sensitivity is set for sections of different heights. When the deviation meets the trigger condition of the corresponding section, the logic control system (600) increases the air curtain supply intensity of the section and adjusts the nozzle tangential deflection angle so that the air curtain jet momentum and the main swirling tangential momentum are dynamically matched. S3: Path control, which adjusts the spiral rising pitch of material particles by adjusting the axial elevation angle of the nozzle, and ensures that the residence time of the material in the cylinder meets the preset threshold according to the material reaction kinetics requirements. S4: Flux self-balancing. By monitoring the output flow fluctuation at the discharge end, when the output flow is continuously lower than the material input, the interception intensity of the air curtain is dynamically weakened to achieve dynamic self-balancing of the system's material flow.

7. The short-process treatment technology according to claim 6, characterized in that, In step S2, the setting logic for the differential pressure trigger sensitivity is as follows: the closer the section is to the material separation zone, the higher its differential pressure trigger sensitivity, in order to cope with the high-frequency disturbance of fine particles; the dynamic matching of the air curtain jet momentum and the main swirling tangential momentum refers to maintaining the air curtain jet speed slightly higher than the main swirling tangential speed.

8. The short-process technology according to claim 6, characterized in that, In step S3, the adjustment of the axial elevation angle adopts a non-linear distribution strategy: a smaller elevation angle is set in the lower region of the cylinder to provide moderate lift, a larger elevation angle is set in the middle reaction region to increase the number of rotations, and a medium elevation angle is set in the upper region to balance the airflow output.

9. The short-process technology according to claim 6, characterized in that, In step S3, closed-loop control based on temperature feedback is also included: when the material temperature at the discharge port is detected to be lower than the preset reaction temperature, the axial elevation angle of the air curtain is reduced to forcibly increase the number of rotations of the material in the cylinder.

10. The short-process technology according to claim 6, characterized in that, It also includes an abnormal self-healing step: when the instantaneous fluctuation rate of the system back pressure indicates that primary scaling has occurred, a pulse cleaning program is executed without interrupting the roasting operation, using instantaneous high-energy airflow to peel off the ash accumulated on the inner wall, and the air curtain control parameters are automatically reset after the peeling is completed.

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