A heat treatment device and system for high-moisture particulate materials across particle size scales

Abstract

The present invention discloses a heat treatment device and system for high-humidity particulate materials across particle size scales. The heat treatment device includes a vortex fluidized bed, a gas buffer, a compressor, and a cyclone drying separator. The gas buffer is disposed around and at the bottom of the vortex fluidized bed. The vortex fluidized bed is communicated with the compressor. The high-temperature gas inside the gas buffer enters the inside of the vortex fluidized bed in a vortex shape to fluidize and dry the material to be fluidized. The gas discharged from the vortex fluidized bed is pressurized by the compressor and then forms a gas-solid mixture with wet materials and enters the cyclone drying separator for preheating and separation. The materials that have completed preheating and separation then enter the vortex fluidized bed for fluidization treatment. The device and system have a compact structure, good space utilization, tight connection of system components, simple operation method, and are convenient for automation.

Description

Technical Field

[0001] The present invention belongs to the technical field of heat treatment environmental protection, and particularly relates to a heat treatment device and system for high-humidity and cross-particle-size scale particulate materials. Background Art

[0002] At present, the soil in chemical industrial parks is damaged by organic pollutants such as petroleum hydrocarbons, polycyclic aromatic hydrocarbons, polychlorinated biphenyls, and chlorobenzenes, and the long-term use of chemical pesticides such as herbicides in farmland remains in the soil, enhancing the drug resistance of diseases, insects, and weeds. Stubborn diseases and pests such as root rot, soft rot, bacterial wilt, virus, blight, and root-knot nematodes have occurred in many places, resulting in crop yield reduction or crop failure. Solving problems such as organic pollutant pollution and diseases, insects, and weeds is an extremely important and urgent hot topic at present.

[0003] The heat treatment method has relatively low cost and is an effective, green, and sustainable method. Its mechanism lies in converting heavy metals from unstable non-residual states to relatively stable residual states, avoiding hazards such as entering the human body through the food chain and causing cell damage, reduced fertility, and cell death; mainly transferring organic pollutants in the form of gas-phase desorption (physical volatilization) or through thermal reactions such as condensation conversion (carbonization) and oxidation (combustion); thermally decomposing soil chemical pesticide residues and inactivating diseases, insects, and weeds by heat contact killing. The soil heat treatment technology has the characteristics of being fast, efficient, thorough, and controllable. However, in the actual application process, due to the large particle size range, high moisture content (25 - 35%), and low thermal conductivity (0.1 - 5 W / m K) of the soil, problems such as low heat and mass transfer rates, long treatment time, high economic cost, and low environmental benefits occur. There is an urgent need to develop a heat treatment drying system and device for soil materials with high humidity and cross-particle-size scale to meet the actual needs.

[0004] At present, the research on gas-solid two-phase flow heat exchange drying is continuously deepening, and the traditional fluidized bed has attracted much attention due to its high heat and mass transfer rates. In the traditional fluidized bed, the interfacial mass, momentum, and heat transfer coefficients are limited by the gas-solid slip velocity and cannot exceed the terminal velocity of the particles in the earth's gravitational field. Especially for Class D particles with large particle size and high density in the Geldart particle classification, the van der Waals force between particles dominates the momentum transfer through drag, forming mesoscopic-scale bubbles and clusters, making it difficult to achieve fluidization. Only at a gas velocity close to the minimum fluidization velocity can the particles be evenly distributed, which is not conducive to sufficient gas-solid heat exchange contact and results in extremely poor heat exchange effect. Therefore, the traditional fluidized bed is not suitable for the fluidized heat and mass transfer of soil.

[0005] For this type of material, a vortex fluidized bed can be adopted. Its basic principle is that the vortex flow of gas acts on the particles to apply drag force. At the same time, under the drive of the gas flow, the particles generate circumferential motion, which sharply increases the centrifugal force of the particles to obtain high gravity (10 - 50g), achieving the balance between drag force and centrifugal force. The high-gravity vortex fluidized bed can achieve a higher gas-solid slip velocity, strengthening the efficient interfacial transfer of mass, momentum, and heat. Compared with the traditional fluidized bed, the heat and mass transfer coefficients of the vortex fluidized bed have been significantly improved, with stronger adaptability to particulate materials across particle size scales, shorter gas-solid interaction time (up to milliseconds), and a more compact device structure, improving the efficiency of industrial processes.

[0006] Due to problems such as severe wear, oil leakage, and gaps in the dynamic vortex fluidized bed machinery, scholars have paid more attention to the static vortex fluidized bed with a static geometric structure, no gaps, and capable of fluidizing particulate materials across particle size scales. However, the static vortex fluidized bed has problems such as high gas consumption, particle entrainment, and low energy utilization efficiency.

[0007] (1) High gas consumption and low energy utilization efficiency, which need to be further improved. Jnyana Ranjan Pati conducted experimental research on rice drying using a vortex chamber. The gas consumption was 400 - 700 Nm 3 / h, while that of the traditional fluidized bed was only 125 - 175 Nm 3 / h (DOI: 10.1080 / 07373937.2015.1093498). Pavitra Singh conducted experimental research on the drying characteristics of rice in a seamless vortex fluidized bed dryer. The gas consumption was 400 - 600 Nm 3 / h (DOI: 10.1080 / 07373937.2021.2018700). The above gas is directly discharged after heat exchange in the vortex chamber, resulting in low energy utilization efficiency. If this part of the waste heat can be effectively utilized, the energy utilization efficiency can be improved to a certain extent.

[0008] (2) Poor adaptability to high-moisture content materials. When the moisture content of the material is high, if it is directly dried in this device, it will inevitably result in greater gas consumption and longer drying time. In the initial stage, the particles are prone to agglomeration, leading to uneven heat exchange and low energy utilization efficiency.

[0009] (3) Serious entrainment of fine particles. Since the gas velocity is relatively large when the gas discharges from the vortex fluidized bed, especially when drying multi-sized materials, it will entrain fine particles, resulting in a reduction in the mass recovery rate of the material.

[0010] In addition, the fluidization of single-sized particulate materials is relatively simple. In actual industrial applications, particulate materials across particle size scales are more widespread, but there are fewer research schemes for the fluidization heat transfer system of such particles.

[0011] Based on this, it is urgent to develop a heat treatment device and system for high-moisture, cross-particle-size-scale granular soil materials with high energy utilization rate, short action time, obvious economic benefits and high environmental benefits. Summary of the Invention

[0012] The object of the present invention is to provide a heat treatment device and system for high-moisture, cross-particle-size-scale granular materials to solve the technical problems existing in the prior art, such as "high moisture content during the heat treatment drying process of materials, difficult fluidization of cross-particle-size-scale particles resulting in poor heat and mass transfer effects, weak adaptability to high-moisture materials, serious entrainment of fine particles, low drying degree and poor efficiency". The device has a compact structure, good space utilization rate, tight connection of system components, simple operation method and is convenient for automation.

[0013] The object of the present invention is achieved by the following technical solutions:

[0014] A heat treatment device for high-moisture, cross-particle-size-scale granular materials includes a vortex fluidized bed, a gas buffer, a compressor and a cyclone drying separator;

[0015] The gas buffer is provided with a gas inlet for introducing high-temperature gas, and the gas buffer is arranged around and at the bottom of the vortex fluidized bed;

[0016] The vortex fluidized bed is respectively provided with a material inlet, a gas outlet and a discharge outlet. The gas outlet is communicated with the compressor; a plurality of uniformly distributed tangential gas inlets are arranged on the circumference of the vortex fluidized bed, and a certain angle is formed between the tangential gas inlet and the circumferential tangent, so that the high-temperature gas inside the gas buffer enters the inside of the vortex fluidized bed in a vortex shape to fluidize and dry the material to be fluidized; the dried material is discharged from the discharge outlet, and the gas enters the compressor from the gas outlet;

[0017] The compressor is connected to the cyclone drying separator. The cyclone drying separator is provided with a material outlet and an exhaust gas outlet, and the material outlet is reconnected to the material inlet of the vortex fluidized bed;

[0018] The gas discharged from the vortex fluidized bed is pressurized by the compressor and enters the cyclone drying separator with wet materials to form a gas-solid mixture for preheating and separation. The materials after preheating and separation, that is, the materials to be fluidized, enter the vortex fluidized bed for fluidization treatment again.

[0019] Preferably, the angle α between the tangential gas inlet and the circumferential tangent outward is 10~15°; the ratio of the effective height to the diameter of the vortex fluidized bed is 0.4~0.6, and the ratio of the total width of the tangential gas inlets to the circumference of the vortex fluidized bed is 0.006~0.048.

[0020] Preferably, the gas inlet on the gas buffer is located at the bottom of the gas buffer, and the top end of the gas buffer is flush with the top end of the vortex fluidized bed.

[0021] Preferably, the gas outlet and the discharge port are respectively located at the central positions of the upper and lower ends of the vortex fluidized bed;

[0022] The diameter of the gas outlet is 30-35% of the diameter of the vortex fluidized bed;

[0023] The diameter of the discharge port is 50-70% of the diameter of the vortex fluidized bed.

[0024] Preferably, a chimney is provided between the gas outlet and the compressor, and the chimney is in the shape of a horn with a gradually decreasing diameter from bottom to top.

[0025] Preferably, a vertical baffle is arranged at the upper central position of the cyclone drying separator, and the length of the vertical baffle is 60-80% of the height of the cyclone drying separator.

[0026] Preferably, the number of the cyclone drying separators is two or more, and they are arranged in series;

[0027] The number of the vortex fluidized beds is two or more, and they are arranged in series.

[0028] A heat treatment system for high-humidity, cross-size-scale particulate materials, comprising a discharging and dust-removing system and a drying air inlet system, and further comprising the heat treatment device as described above;

[0029] The discharging and dust-removing system comprises a discharger and a dust collector; the discharger is connected to the discharge port of the vortex fluidized bed for discharging the dried materials; both ends of the dust collector are respectively connected to the exhaust gas outlet of the cyclone drying separator and the drying air inlet system for dust-removing the exhaust gas discharged from the cyclone drying separator, and the dust-removed exhaust gas is conveyed to the drying air inlet system;

[0030] The drying air inlet system comprises a condenser, a fan, a heater and a gas storage tank connected in sequence. The dried exhaust gas is condensed by the condenser, heated by the heater under the action of the fan and then stored in the gas storage tank; the gas storage tank is communicated with the gas inlet of the gas buffer through a gas conveying pipeline, and a regulating valve, a temperature sensor, a pressure gauge and a flow meter are arranged on the gas conveying pipeline; the drying air inlet system further comprises a gas control system electrically connected to the fan, the heater, the regulating valve, the temperature sensor, the pressure gauge and the flow meter, and the gas control system is used to control high-temperature gas meeting the set temperature, flow rate and pressure to enter the gas buffer.

[0031] Preferably, it further includes a feeding system;

[0032] The feeding system includes a first feeder, a second feeder, and a solid control system;

[0033] A material conveying pipeline is provided between the compressor and the cyclone drying separator, and the outlet end of the first feeder is communicated with the material conveying pipeline; the second feeder is located between the material outlet of the cyclone drying separator and the material inlet of the vortex fluidized bed;

[0034] The solid control system is electrically connected to the first feeder and is used to control the wet material that meets the set conditions to be mixed with the high-pressure gas discharged from the compressor and enter the cyclone drying separator;

[0035] The solid control system is also electrically connected to the second feeder and is used to control the material to be fluidized that meets the set conditions to enter the vortex fluidized bed.

[0036] Preferably, a check valve is provided on the material conveying pipeline downstream of the first feeder, and the check valve is electrically connected to the solid control system.

[0037] Compared with the prior art, the heat treatment device provided by this application has the following advantages:

[0038] (1) The waste heat of the gas discharged from the vortex fluidized bed is effectively utilized, preheated in the cyclone drying separator after being mixed with the wet material, so that the moisture in the wet material is discharged in a non-phase change manner, overcoming the characteristic that the vortex fluidized bed is not very adaptable to high moisture content materials, achieving the purpose of saving energy, improving the energy utilization level, and realizing the cascade utilization of energy; moreover, the recycling of gas is realized, and the gas consumption is reduced.

[0039] (2) The use of the cyclone drying separator can reduce the fine particles entrained in the gas and reduce the mass loss rate of the material.

[0040] (3) Through the combination of the static vortex fluidized bed and the gas buffer, not only the drawback of the single heat exchange method in the static vortex fluidized bed is changed, but also the uniformity of the tangential gas flow and velocity is improved, making the fluidized heat exchange more uniform and the dehydration rate higher.

[0041] (4) Under the action of gravity, different particle size particles are affected by the terminal velocity differently. Especially for the particle mixture covering Class A and Class D, due to the influence of van der Waals force and liquid bridge force, it is difficult to fluidize the traditional vertical vortex fluidized bed with lower end air inlet. However, the vortex fluidized bed provided by this application has side air inlet, overcoming the influence of gravity, increasing the slip velocity between gas and solid, strengthening heat transfer, and being highly adaptable to cross-particle sizes (including Class A and Class D). Description of the Drawings

[0042] Figure 1 Schematic structural diagram of the heat treatment device provided by the present invention;

[0043] Figure 2 Schematic diagram of the fluidization principle of the vortex fluidized bed of the present invention;

[0044] Figure 3 is Figure 1 Top view of the combined structure of the material discharger, vortex fluidized bed and chimney in

[0045] Figure 4 is Figure 1 Axonometric top view of the combined structure of the material discharger, vortex fluidized bed and chimney in

[0046] Figure 5 is Figure 1 Bottom view of the combined structure of the material discharger, vortex fluidized bed and chimney in

[0047] Figure 6 is Figure 1 Axonometric bottom view of the combined structure of the material discharger, vortex fluidized bed and chimney in

[0048] Figure 7 is Figure 1 Cross-sectional view of the combined structure of the material discharger, vortex fluidized bed and chimney in

[0049] Figure 8 is Figure 1 Axonometric bottom view of the gas buffer in

[0050] Figure 9 is Figure 1 Axonometric top view of the gas buffer in

[0051] Figure 10 is Figure 1 Schematic diagram of the cyclone drying separator in

[0052] Figure 11 Flow chart of the heat treatment system provided by the present invention.

[0053] Wherein: 1 - First feeder, 2 - Cyclone drying separator, 3 - Discharger, 4 - Vortex fluidized bed, 5 - Gas buffer, 6 - Compressor, 7 - Second feeder, 8 - Chimney, 9 - Tangential gas inlet, 10 - Material inlet; 11 - Material; 12 - Gas outlet; 13 - Discharge pipeline; A - Fluidization zone; B - Freeboard zone; Dashed arrows indicate the gas flow direction, and solid arrows indicate the material flow direction. Detailed implementation manners

[0054] Static vortex fluidized beds consume large amounts of gas. After vortex fluidization and heat exchange with wet materials, they are directly discharged into the environment, carrying fine particles with them. This results in significant gas waste, low material recovery rates, and reduced energy utilization. They are also not very adaptable to materials with high moisture contents, primarily because the dehydration process involves a phase change reaction, which inevitably results in greater gas consumption and longer reaction times. Particle agglomeration leads to uneven heat exchange, resulting in low energy utilization. Furthermore, this fluidized bed has a single heat exchange mechanism, primarily due to intense heat and mass transfer in the narrow fluidized zone of the static vortex fluidized bed, while no heat exchange occurs in the larger drying zone, which also negatively impacts the drying process.

[0055] To solve the above problems, the present invention provides a heat treatment device for high-humidity, cross-particle size granular materials, such as Figures 1 to 10 As shown, it includes a vortex fluidized bed 4, a gas buffer 5, a compressor 6 and a cyclone dryer separator 2.

[0056] The gas buffer 5 is provided with a gas inlet for introducing high-temperature gas, and the gas buffer is arranged around the four sides and bottom of the vortex fluidized bed.

[0057] The vortex fluidized bed 4 is equipped with a material inlet 10, a gas outlet, and a discharge port. The gas outlet is connected to the compressor 6. Multiple tangential gas inlets 9 are evenly distributed around the circumference of the vortex fluidized bed 4. These tangential gas inlets form a certain angle with the tangent of the circumference, allowing the high-temperature gas inside the gas buffer to enter the vortex fluidized bed from the side in a vortex shape, fluidizing and drying the material to be fluidized. The dried material is discharged from the discharge port, and the gas enters the compressor from the gas outlet.

[0058] The compressor 6 is connected to the cyclone dryer separator 2. The cyclone dryer separator is provided with a material outlet and an exhaust gas outlet. The material outlet is then connected to the material inlet of the vortex fluidized bed 4 to complete a closed cycle.

[0059] The gas discharged from the vortex fluidized bed 4 is pressurized by the compressor, and then carries the wet material to form a gas-solid mixture and enters the cyclone dryer separator for preheating and separation. The preheated and separated material, i.e., the material to be fluidized, enters the vortex fluidized bed for fluidized drying.

[0060] The specific working process of the heat treatment device provided in this application is as follows:

[0061] The gas buffer 5 is arranged around the vortex fluidized bed to provide high-speed tangential gas to the vortex fluidized bed 4 to fluidize the preheated material discharged from the cyclone drying separator. The preheated material is fluidized near the circumferential wall of the fluidized bed under the action of centrifugal force and drag force to achieve material drying. When the drag force is greater than the centrifugal force, the material is discharged from the material outlet to obtain dried material particles.

[0062] As Figure 2 shown, the area near the circumferential wall surface of the vortex fluidized bed is the fluidization zone A, and the larger area inside the fluidization zone A is the freeboard zone B. In the fluidization zone A, the gas applies drag force to fluidize the material. The freeboard zone is basically the place where the waste gas after heat exchange by the gas flows through. Finally, the waste gas is discharged through the gas outlet. The gas buffer 5 of the present application is also arranged at the bottom of the vortex fluidized bed. Therefore, the freeboard zone of the vortex fluidized bed 4 can be affected by the heat conduction of the gas buffer 5 below, solving the problem of single heat exchange method. The material about to be discharged after passing through the freeboard zone is affected by the heat conduction and thermal radiation of the lower bottom plate of the vortex fluidized bed 4, further improving the drying degree of the material particles.

[0063] The gas after heat exchange in the vortex fluidized bed continuously moves in a swirling manner inward and is discharged from the gas outlet above the central position. After being pressurized by the compressor 6, it entrains wet material particles to form a gas-solid mixture. The heat exchange and separation of the gas and solid are completed in the cyclone drying separator 2. It not only recovers and utilizes the waste heat of the gas discharged from the vortex fluidized bed, but also preliminarily dries the wet material before entering the vortex fluidized bed, enabling the moisture in the wet material to be discharged in a non-phase change manner, overcoming the characteristic that the vortex fluidized bed is not highly adaptable to materials with high moisture content. Moreover, the fine material particles entrained in the high-speed gas discharged from the vortex fluidized bed can be recovered through the cyclone drying separator, reducing the environmental pollution and material loss caused by direct discharge into the atmosphere.

[0064] In summary, compared with the prior art, the heat treatment device provided by the present application has the following advantages:

[0065] (1) Effectively utilizes the waste heat of the gas discharged from the vortex fluidized bed, preheats the wet material after mixing with the wet material in the cyclone drying separator, enables the moisture in the wet material to be discharged in a non-phase change manner, overcomes the characteristic that the vortex fluidized bed is not highly adaptable to materials with high moisture content, achieves the purpose of saving energy, improving the energy utilization level, and realizing the cascade utilization of energy; and realizes the recovery and utilization of the gas, reducing the gas consumption.

[0066] (2) The cyclone drying separator can reduce the fine particles entrained in the gas, reducing the mass loss rate of the material.

[0067] (3) Through the combination of the static vortex fluidized bed and the gas buffer, not only the drawback of single heat exchange method in the static vortex fluidized bed is changed, but also the uniformity of the tangential gas flow rate and velocity is improved, making the fluidized heat exchange more uniform and the dehydration rate higher.

[0068] (4) Under the action of gravity, particles of different sizes are affected differently by the terminal velocity. This is especially true for mixtures of particles of types A and D. Due to the influence of van der Waals forces and liquid bridge forces, a traditional vertical vortex fluidized bed with air inlet from the bottom is difficult to fluidize. However, the vortex fluidized bed provided in this application uses air inlet from the side, overcoming the influence of gravity. This increases the slip velocity between the gas and the solid, enhances heat exchange, and has strong adaptability to a wide range of particle sizes (including types A and D).

[0069] Preferably, the angle α between the tangential gas inlet 9 and the circumferential tangent is 10-15°; the effective height-to-diameter ratio of the vortex fluidized bed 4 is 0.4-0.6, and the ratio of the total width of the tangential gas inlet to the circumference of the vortex fluidized bed is 0.006-0.048. The gas inlet width is larger than the equivalent diameter of the material volume. The vortex flow of gas fluidizes the material, causing intense heat and mass transfer in both the circumferential and radial directions. The vortex fluidized bed under the above parameters facilitates mixing of gas and material, has a large gas-solid contact area, and achieves a good fluidization effect.

[0070] Preferably, the gas inlet of the gas buffer 5 is located at the bottom of the gas buffer and is connected to gas delivery pipelines (four gas delivery pipelines are shown in the figure). The high-temperature gas first enters the gas buffer from the bottom and then evenly fills the entire gas buffer from bottom to top. The top of the gas buffer is flush with the top of the vortex fluidized bed to ensure uniform tangential gas flow and velocity entering the vortex fluidized bed. The diameter and height of the gas buffer 5 (the height can be increased from the bottom while the top remains flush with the vortex fluidized bed) can be adjusted according to drying conditions and material properties to increase the buffer gas volume to meet the gas requirements of high-moisture materials.

[0071] Preferably, the gas outlet and the discharge port are located at the center of the upper and lower ends of the vortex fluidized bed respectively; the diameter of the gas outlet is 30-35% of the diameter of the vortex fluidized bed; the diameter of the discharge port is 50-70% of the diameter of the vortex fluidized bed.

[0072] The material inlet 10 is located at one side of the upper end of the vortex fluidized bed 4 .

[0073] Preferably, a chimney 8 is provided between the gas outlet and the compressor. The chimney is trumpet-shaped with a diameter gradually decreasing from bottom to top. The trumpet-shaped chimney can conveniently collect the gas discharged from the vortex fluidized bed and further increase the flow rate and pressure of the exhaust gas.

[0074] Preferably, a vertical baffle is provided at the upper center of the cyclone drying separator 2, and the length of the vertical baffle is 60-80% of the height of the cyclone drying separator, so as to facilitate sufficient heat exchange of gas-solid materials and slow down the gas discharge speed.

[0075] Preferably, the number of the cyclone drying separators 2 is more than two and they are arranged in series; the number of the vortex fluidized beds 4 is more than two and they are arranged in series, which can further improve the energy utilization level and efficiency, improve the dehydration efficiency and degree of the wet material, and increase the processing quality per unit time, but generally not exceeding 3.

[0076] On the basis of the above, the present application further provides a heat treatment system for high-moisture, cross-particle-size-scale particulate materials, such as Figure 11 shown, including the heat treatment device, the discharging and dust-removing system and the drying air inlet system as described above. The high-temperature gas flowing out of the drying air inlet system and the wet material are subjected to cyclone drying and fluidized heat exchange in the heat treatment device, and then the dried material and the waste gas are collected and dust-removed through the discharging and dust-removing system, and the waste gas is recycled after being heated by the drying air inlet system. Specifically:

[0077] The heat treatment device is as described above. The wet material is first preheated in the cyclone drying separator to remove part of the water in the wet material, and then undergoes vortex fluidized heat exchange in the vortex fluidized bed body and is discharged to obtain the dried material, realizing the secondary drying of the high-moisture, cross-particle-size-scale particulate materials.

[0078] The discharging and dust-removing system includes a discharger 3 and a dust collector; the discharger is connected to the discharge port of the vortex fluidized bed 4 and is used for discharging the dried material.

[0079] Preferably, the discharger is a calabash mouth structure with a central contraction, and a lateral discharge pipe 13 is provided at the bottom of the calabash mouth and is slightly inclined downward, which is convenient for discharging. After the gas-solid two-phase heat exchange near the circumferential wall surface of the fluidized bed body, the gas phase flows upward under the action of vortex and buoyancy, and the solid phase flows downward under the action of gravity and enters the discharger, accumulates to a certain height therein, and finally discharges from the side, which can avoid the influence of the discharger outlet on the pressure in the bed, improve the gas-solid two-phase flow stability in the fluidized bed, and at the same time reduce the particle entrainment at the gas outlet.

[0080] The two ends of the dust collector are respectively connected to the waste gas outlet of the cyclone drying separator and the drying air inlet system, and are used for dust-removing the waste gas discharged from the cyclone drying separator, and the dust-removed waste gas is transported to the drying air inlet system for heating.

[0081] The drying air inlet system includes a condenser, a fan, a heater, and a gas storage tank connected in sequence. The dried waste gas is condensed by the condenser, heated by the heater under the action of the fan, and then stored in the gas storage tank. The gas storage tank is connected to the gas inlet of the gas buffer through a gas transmission pipeline, and a regulating valve, a temperature sensor, a pressure gauge, and a flow meter are provided on the gas transmission pipeline. The drying air inlet system further includes a gas control system electrically connected to the fan, the heater, the regulating valve, the temperature sensor, the pressure gauge, and the flow meter. The gas control system is used to control high-temperature gas that meets the set temperature, flow rate, and pressure to enter the gas buffer. Specifically, the power of the fan and the heater and the opening of the regulating valve can be adjusted through the gas control system to meet the heat exchange requirements of the heat treatment device.

[0082] The energy source of the heater can be provided by the combustion of any one or more of fuels such as natural gas, coal, or biomass.

[0083] Preferably, the heat treatment system provided by the present application further includes a feeding system; the feeding system includes a first feeder 1, a second feeder 7, and a solid control system.

[0084] A material conveying pipeline is provided between the compressor 6 and the cyclone drying separator 2. The outlet end of the first feeder is connected to the material conveying pipeline. The wet material enters the material conveying pipeline through the first feeder and is mixed with the high-pressure gas discharged by the compressor to form a gas-solid mixture and then conveyed to the cyclone drying separator. The second feeder 7 is located between the material outlet of the cyclone drying separator 2 and the material inlet of the vortex fluidized bed 4, and is used to supply the material to be fluidized and treated to the vortex fluidized bed.

[0085] The first feeder 1 and the second feeder 7 are preferably screw feeders, including a hopper, a pushing screw in the hopper, and a rotary seal discharge valve provided at the bottom of the hopper.

[0086] The solid control system is electrically connected to the first feeder and is used to control the high-moisture material that meets the set conditions (mainly mass and flow rate) to be mixed with the high-pressure gas discharged by the compressor and enter the cyclone drying separator.

[0087] The solid control system is also electrically connected to the second feeder and is used to control the material to be fluidized and treated that meets the set conditions (mainly mass and flow rate) to enter the vortex fluidized bed.

[0088] Further preferably, a check valve is provided on the material conveying pipeline downstream of the first feeder. The check valve is electrically connected to the solid control system. The setting of the check valve can effectively prevent the reverse flow of materials.

[0089] The specific working process of the heat treatment system provided by the present application is as follows:

[0090] Under the action of the fan, the gas enters the heater and is heated to a certain temperature, then enters the gas storage tank. The power of the fan and the heater and the opening degree of the regulating valve are adjusted through the gas control system to meet the heat exchange requirements of the heat treatment device. The high-temperature gas undergoes fluidized heat exchange in the vortex fluidized bed and then flows into the compressor 6 through the chimney 8 at the central position of the vortex fluidized bed 4. The high-pressure intermediate gas entrains the highly humid material of the first feeder 1 and enters the cyclone drying separator 2 through the check valve. After heat exchange and separation are completed, the gas is discharged, dusted by the dust collector, and then returned to the heater through the fan to complete a cycle; the preliminarily dried wet material enters the vortex fluidized bed 4 through the second feeder 7 and is fluidized and heat-exchanged and dried by the high-temperature gas entering through the gas buffer 5, and then the dried granular material is obtained through the discharger 3. The solid control system adjusts the opening degrees of the rotary seal valves of the first feeder and the second feeder and the check valve to meet the heat exchange requirements of the heat treatment device.

[0091] The present application provides a method applicable to the above heat treatment device and heat treatment system, including the following steps:

[0092] S1: Feed the highly humid material with a density of 1000 - 3500 kg / m 3 , an equivalent volume diameter of 50 - 3000 μm, and a water content of 30 - 80% into the hopper of the first feeder 1.

[0093] S2: Turn on the fan and the heater. After a period of time, adjust the temperature of the gas storage tank to 50 - 800 °C by the gas control system, open the regulating valve to make the flow rate 300 - 800 Nm 3 / h. At the same time, turn on the compressor 6 and control the rotary seal valves of the first feeder 1 and the second feeder 7 by the solid control system to make the high-temperature gas circulate stably in the system. Stay for several minutes.

[0094] Step 3: Use the solid control system to turn the screws of the first feeder 1 and the second feeder 7, so that the feeding speed of the highly humid material in the first feeder 1 is 0.01 - 1 kg / s, and the speed of the first feeder is slightly greater than that of the second feeder. To prevent backflow, a check valve is set downstream of the first feeder 1. The highly humid material first completes primary drying in the cyclone drying separator 2, enters the vortex fluidized bed 4 through the second feeder 7, and is further heat-exchanged to make the water content of the material reach below 14%, and the main material is discharged from the outlet of the discharger 3. The gas discharged from the cyclone drying separator 2 passes through the bag dust collector to obtain fine secondary dried materials, and the waste gas is cooled by the condenser to remove moisture and then returns to the drying air inlet system to achieve the purpose of energy saving.

[0095] The following further describes the present invention with specific embodiments. The heat treatment device shown in Figure 1 is used in the embodiments, such as the heat treatment system shown in Figure 11 . It should be noted that when adding wet materials Figure 11In the middle hopper, referring to the structural parameters and working conditions shown in Table 1, the high-temperature gas first runs in the system for several minutes to ensure the stability of the device operation.

[0096] Table 1

[0097]

[0098] Example 1

[0099] High-moisture materials with a density of 2600 kg / m 3 , an equivalent volume diameter of 2000 μm and a water content of 30% are conveyed into the hopper of the first feeder 1. The fan and heater are turned on. After a period of time, the gas control system adjusts the temperature of the gas storage tank to 50 °C, and the regulating valve is opened to make the flow rate 400 Nm 3 / h. At the same time, the compressor 6 is turned on and the rotary seal valves of the first feeder 1 and the second feeder 7 are controlled by the solid control system, so that the high-temperature gas circulates stably in the system and stays for several minutes. The screw of the first feeder 1 is turned by the solid control system to make the feeding speed of the high-moisture materials in the first feeder 1 0.5 kg / s. To prevent backflow, a check valve is arranged downstream of the first feeder 1. The high-moisture materials are first primarily dried in the cyclone drying separator 2 and then enter the static vortex fluidized bed 4 with 36 inlet ports (i.e., tangential gas inlets), an inlet port width of 4 mm, an inlet port angle of 10°, a diameter of 0.5 m, a height of 0.25 m, a discharge port diameter of 0.3 m, and a gas outlet diameter of 0.18 m through the second feeder 7. Further heat exchange is carried out to make the water content of the materials reach below 14%, and the main materials are discharged by the discharger 3. The gas discharged from the cyclone drying separator 2 passes through the bag filter to obtain fine secondary dried materials, and the waste gas is cooled by the condenser to remove moisture and then returned to the drying air inlet system for recycling to achieve the purpose of energy saving.

[0100] Example 2

[0101] High-moisture materials with a density of 3000 kg / m 3 , an equivalent volume diameter of 3000 μm and a water content of 35% are conveyed into the hopper of the first feeder 1. The fan and heater are turned on. After a period of time, the gas control system adjusts the temperature of the gas storage tank to 100 °C, and the regulating valve is opened to make the flow rate 400 Nm 3 / h. Meanwhile, turn on the compressor 6 and the rotary seal valves of the first feeder 1 and the second feeder 7 controlled by the solid control system to enable the high-temperature gas to circulate stably in the system and stay for several minutes. The solid control system toggles the screw of the first feeder 1 to make the feeding speed of the high-moisture material in the first feeder 1 0.5 kg / s. To prevent backflow, a check valve is set downstream of the first feeder 1. The high-moisture material first completes primary drying in the cyclone drying separator 2, enters the static vortex fluidized bed 4 with 36 air inlets, an air inlet width of 4 mm, an air inlet angle of 13°, a diameter of 0.5 m, a height of 0.25 m, a discharge port diameter of 0.3 m, and a gas outlet diameter of 0.18 m through the second feeder 7, and further exchanges heat to make the water content of the material reach below 14%. It is discharged by the discharger 3 to obtain the main material. The gas discharged from the cyclone drying separator 2 passes through a bag filter to obtain fine secondary dried materials. The waste gas is cooled by a condenser to remove moisture and then returns to the drying air inlet system for recycling, achieving the purpose of energy conservation.

[0102] Example 3

[0103] The high-moisture material with a density of 3200 kg / m 3 , an equivalent volume diameter of 400 μm and a water content of 30% is transported into the hopper of the first feeder 1. Turn on the fan and the heater. After a period of time, the gas control system adjusts the temperature of the gas storage tank to 150 °C, and opens the regulating valve to make the flow rate 500 Nm 3 / h. Meanwhile, turn on the compressor 6 and the rotary seal valves of the first feeder 1 and the second feeder 7 controlled by the solid control system to enable the high-temperature gas to circulate stably in the system and stay for several minutes. The solid control system toggles the screw of the first feeder 1 to make the feeding speed of the high-moisture material in the first feeder 1 0.5 kg / s. To prevent backflow, a check valve is set downstream of the first feeder 1. The high-moisture material first completes primary drying in the cyclone drying separator 2, enters the vortex fluidized bed 4 with 20 air inlets, an air inlet width of 2 mm, an air inlet angle of 13°, a diameter of 0.3 m, a height of 0.15 m, a discharge port diameter of 0.18 m, and a gas outlet diameter of 0.1 m through the second feeder 7, and further exchanges heat to make the water content of the material reach below 14%. It is discharged by the discharger 3 to obtain the main material. The gas discharged from the cyclone drying separator 2 passes through a bag filter to obtain fine secondary dried materials. The waste gas is cooled by a condenser to remove moisture and then returns to the drying air inlet system for recycling, achieving the purpose of energy conservation.

[0104] Example 4

[0105] The high-moisture material with a density of 1800 kg / m 3, high-moisture materials with an equivalent volume diameter of 300 μm and a water content of 55% are conveyed into the hopper of the first feeder 1. The fan and heater are turned on. After a period of time, the gas control system adjusts the temperature of the gas storage tank to 200 °C, and the regulating valve is opened to make the flow rate 500 Nm 3 / h. At the same time, the compressor 6 is turned on, and the rotary seal valves of the first feeder 1 and the second feeder 7 are controlled by the solid control system to enable the high-temperature gas to circulate stably in the system and stay for several minutes. The screw of the first feeder 1 is toggled by the solid control system to make the feeding speed of the high-moisture materials in the first feeder 1 0.8 kg / s. To prevent backflow, a check valve is set downstream of the first feeder 1. The high-moisture materials are first primarily dried in the cyclone drying separator 2, and then enter the vortex fluidized bed 4 with 20 air inlets, an air inlet width of 2 mm, an air inlet angle of 13°, a diameter of 0.3 m, a height of 0.15 m, a discharge port diameter of 0.18 m, and a gas outlet diameter of 0.1 m through the second feeder 7. Further heat exchange is carried out to make the water content of the materials reach below 14%, and the main materials are discharged by the discharger 3. The gas discharged from the cyclone drying separator 2 is passed through a bag filter to obtain fine secondary dried materials. The waste gas is cooled by a condenser to remove moisture and then returned to the drying air inlet system for recycling, achieving the purpose of energy conservation.

[0106] Example 5

[0107] High-moisture materials with a density of 1100 kg / m 3 , an equivalent volume diameter of 80 μm and a water content of 50% are conveyed into the hopper of the first feeder 1. The fan and heater are turned on. After a period of time, the gas control system adjusts the temperature of the gas storage tank to 500 °C, and the regulating valve is opened to make the flow rate 700 Nm 3 / h. At the same time, the compressor 6 is turned on, and the rotary seal valves of the first feeder 1 and the second feeder 7 are controlled by the solid control system to enable the high-temperature gas to circulate stably in the system and stay for several minutes. The screw of the first feeder 1 is toggled by the solid control system to make the feeding speed of the high-moisture materials in the first feeder 1 0.5 kg / s. To prevent backflow, a check valve is set downstream of the first feeder 1. The high-moisture materials are first primarily dried in the cyclone drying separator 2, and then enter the vortex fluidized bed 4 with 36 air inlets, an air inlet width of 3 mm, an air inlet angle of 10°, a diameter of 0.5 m, a height of 0.25 m, a discharge port diameter of 0.3 m, and a gas outlet diameter of 0.18 m through the second feeder 7. Further heat exchange is carried out to make the water content of the materials reach below 14%, and the main materials are discharged by the material discharger 3. The gas discharged from the cyclone drying separator 2 is passed through a bag filter to obtain fine secondary dried materials. The waste gas is cooled by a condenser to remove moisture and then returned to the drying air inlet system for recycling, achieving the purpose of energy conservation.

[0108] Example 6

[0109] High-moisture materials with a density of 1100 kg / m 3 , an equivalent volume diameter of 80 μm, and a water content of 45% are fed into the hopper of the first feeder 1. The fan and heater are turned on. After a period of time, the temperature of the gas storage tank is adjusted by the gas control system to 700 °C, and the regulating valve is opened to make the flow rate 700 Nm 3 / h. At the same time, the compressor 6 is turned on, and the rotary seal valves of the first feeder 1 and the second feeder 7 are controlled by the solid control system to enable the high-temperature gas to circulate stably in the system and stay for several minutes. The screw of the first feeder 1 is rotated by the solid control system to make the feeding speed of the high-moisture materials in the first feeder 1 0.5 kg / s. To prevent backflow, a check valve is set downstream of the first feeder 1. The high-moisture materials are first primarily dried in the cyclone drying separator 2 and then enter the vortex fluidized bed 4 with 36 air inlets, an air inlet width of 3 mm, an air inlet angle of 10°, a diameter of 0.5 m, a height of 0.25 m, a discharge port diameter of 0.3 m, and a gas outlet diameter of 0.18 m through the second feeder 7. Further heat exchange is carried out to make the water content of the materials reach below 14%, and the main materials are discharged by the discharger 3. The gas discharged from the cyclone drying separator 2 is passed through a bag filter to obtain fine secondary dried materials. The waste gas is cooled by a condenser to remove moisture and then returned to the drying air inlet system for recycling to achieve the purpose of energy saving.

[0110] It is worth noting that the above application example belongs to the case of a single equivalent volume diameter, while in actual industrial applications, including soil particle sizes, most are multi-scale particle materials. Therefore, to illustrate the applicability of the present invention to multi-scale particle materials, Example 7 is used to illustrate with three cross-scale equivalent volume diameters, and other multi-particle materials that follow normal distribution, logarithmic distribution, etc. will not be illustrated one by one.

[0111] Example 7

[0112] High-moisture multi-scale materials with a density of 1500 kg / m 3 , three equivalent volume diameters of 80 μm, 1000 μm, 3000 μm, and a water content of 45% are fed into the hopper of the first feeder 1. The fan and heater are turned on. After a period of time, the temperature of the gas storage tank is adjusted by the gas control system to 180 °C, and the regulating valve is opened to make the flow rate 700 Nm 3 / h. Meanwhile, the compressor 6 is turned on, and the rotary seal valves of the first feeder 1 and the second feeder 7 are controlled by the solid control system, so that the high-temperature gas circulates stably in the system and stays for several minutes. The screw of the first feeder 1 is toggled by the solid control system to make the feeding speed of the high-moisture material in the first feeder 1 be 1 kg / s. To prevent backflow, a check valve is arranged downstream of the first feeder 1. The high-moisture material first completes primary drying in the cyclone drying separator 2 and enters the static vortex fluidized bed 4 with 36 air inlets, an air inlet width of 6 mm, an air inlet angle of 10°, a diameter of 0.5 m, a height of 0.25 m, a discharge port diameter of 0.3 m, and a gas outlet diameter of 0.18 m through the second feeder 7, and further exchanges heat to make the water content in the material reach below 14%, and the main material is discharged by the discharger 3. The gas discharged from the cyclone drying separator 2 is passed through a bag filter to obtain fine secondary dried materials, and the waste gas is cooled by a condenser to remove moisture and then returned to the drying air inlet system for recycling, achieving the purpose of energy conservation.

[0113] After statistics, the material loss rate of the above embodiments is about 3 - 6%, the dehydration rate is above 85%, and the gas basically has no loss after being recycled, improving the energy utilization efficiency.

[0114] Although the preferred embodiments of the present invention have been described, those skilled in the art can make additional changes and modifications once they know the basic creative concept. Therefore, the appended claims are intended to be construed to include the preferred embodiments and all changes and modifications falling within the scope of the present invention. Obviously, those skilled in the art can make various changes and variations to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalent technologies, the present invention also intends to include these modifications and variations.

Claims

1. A heat treatment device for high-moisture, cross-particle-size-scale particulate materials, characterized in that, It includes a vortex fluidized bed, a gas buffer, a compressor and a cyclone drying separator; The gas buffer is provided with a gas inlet for introducing high-temperature gas, and the gas buffer is arranged around and at the bottom of the vortex fluidized bed; The vortex fluidized bed is respectively provided with a material inlet, a gas outlet and a discharge outlet. The gas outlet is communicated with the compressor; a plurality of uniformly distributed tangential gas inlets are arranged on the circumference of the vortex fluidized bed, and the tangential gas inlet forms a certain angle with the circumferential tangent, so that the high-temperature gas inside the gas buffer enters the inside of the vortex fluidized bed in a vortex shape to fluidize and dry the material to be fluidized; the dried material is discharged from the discharge outlet, and the gas enters the compressor from the gas outlet; The compressor is connected to the cyclone drying separator, and a material conveying pipeline is arranged between the compressor and the cyclone drying separator. The material conveying pipeline is communicated with a first feeder, and wet material enters the material conveying pipeline through the first feeder; the cyclone drying separator is provided with a material outlet and an exhaust gas outlet, and the material outlet is reconnected to the material inlet of the vortex fluidized bed; The gas discharged from the vortex fluidized bed is pressurized by the compressor and enters the cyclone drying separator with wet material to form a gas-solid mixture for preheating and separation. The material after preheating and separation, that is, the material to be fluidized, enters the vortex fluidized bed for fluidization treatment again; the discharge outlet of the vortex fluidized bed is connected with a discharger, and the discharger is a gourd mouth structure with a central contraction. A lateral discharge pipeline is arranged at the bottom of the gourd mouth, and the discharge pipeline is slightly inclined downward.

2. The heat treatment device for high-moisture, cross-particle-size-scale particulate materials according to claim 1, characterized in that The angle α between the tangential gas inlet and the circumferential tangent outward is 10-15°; the ratio of the effective height to the diameter of the vortex fluidized bed is 0.4-0.6, and the ratio of the total width of the tangential gas inlets to the circumference of the vortex fluidized bed is 0.006-0.

048.

3. The heat treatment device for high-moisture, cross-particle-size-scale particulate materials according to claim 1, characterized in that The gas inlet on the gas buffer is located at the bottom of the gas buffer, and the top of the gas buffer is flush with the top of the vortex fluidized bed.

4. The heat treatment device for high-moisture, cross-particle-size-scale particulate materials according to claim 1, characterized in that The gas outlet and the discharge outlet are respectively located at the upper and lower center positions of the vortex fluidized bed; The diameter of the gas outlet is 30-35% of the diameter of the vortex fluidized bed; The diameter of the discharge outlet is 50-70% of the diameter of the vortex fluidized bed.

5. The heat treatment device for high-moisture, cross-particle-size-scale particulate materials according to claim 1, characterized in that A chimney is arranged between the gas outlet and the compressor, and the chimney is in a trumpet shape with a gradually decreasing diameter from bottom to top.

6. The heat treatment device for high-moisture, cross-particle-size-scale particulate materials according to claim 1, characterized in that A vertical baffle is provided at the upper central position of the cyclone drying separator, and the length of the vertical baffle is 60% to 80% of the height of the cyclone drying separator.

7. The heat treatment device for highly humid and cross-particle size scale particulate materials according to claim 1, wherein the number of the cyclone drying separators is more than two, and they are arranged in series; the number of the vortex fluidized beds is more than two, and they are arranged in series.

8. A heat treatment system for high-moisture, cross-particle-size-scale particulate materials, characterized in that, It includes a discharge dust removal system and a drying air inlet system, and further includes the heat treatment device according to any one of claims 1 to 7; The discharge dust removal system includes a discharger and a dust collector; the discharger is connected to the discharge port of the vortex fluidized bed for discharging the dried materials; both ends of the dust collector are respectively connected to the exhaust gas outlet of the cyclone drying separator and the drying air inlet system for dust removal of the exhaust gas discharged from the cyclone drying separator, and the dust-removed exhaust gas is transported to the drying air inlet system; The drying air inlet system includes a condenser, a fan, a heater and a gas storage tank connected in sequence. The dried exhaust gas is condensed by the condenser, heated by the heater under the action of the fan and then stored in the gas storage tank; the gas storage tank is communicated with the gas inlet of the gas buffer through a gas transmission pipeline, and a regulating valve, a temperature sensor, a pressure gauge and a flow meter are provided on the gas transmission pipeline; the drying air inlet system further includes a gas control system electrically connected to the fan, the heater, the regulating valve, the temperature sensor, the pressure gauge and the flow meter, and the gas control system is used to control high-temperature gas that meets the set temperature, flow rate and pressure to enter the gas buffer.

9. The heat treatment system for high-moisture, cross-particle-size-scale particulate materials according to claim 8, characterized in that, It further includes a feeding system; The feeding system includes a first feeder, a second feeder and a solid control system; A material conveying pipeline is provided between the compressor and the cyclone drying separator, and the outlet end of the first feeder is communicated with the material conveying pipeline; the second feeder is located between the material outlet of the cyclone drying separator and the material inlet of the vortex fluidized bed; The solid control system is electrically connected to the first feeder and is used to control the wet materials that meet the set conditions to be mixed with the high-pressure gas discharged from the compressor and enter the cyclone drying separator; The solid control system is also electrically connected to the second feeder and is used to control the materials to be fluidized and processed that meet the set conditions to enter the vortex fluidized bed.

10. The heat treatment system for high-humidity particulate materials across particle size scales according to claim 9, wherein, A check valve is provided on the material conveying pipeline downstream of the first feeder, and the check valve is electrically connected to the solid control system.

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