CN110926111B - Moving bed drying method and device for materials - Google Patents
Moving bed drying method and device for materials Download PDFInfo
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- CN110926111B CN110926111B CN201911108592.8A CN201911108592A CN110926111B CN 110926111 B CN110926111 B CN 110926111B CN 201911108592 A CN201911108592 A CN 201911108592A CN 110926111 B CN110926111 B CN 110926111B
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F26—DRYING
- F26B—DRYING SOLID MATERIALS OR OBJECTS BY REMOVING LIQUID THEREFROM
- F26B3/00—Drying solid materials or objects by processes involving the application of heat
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F26—DRYING
- F26B—DRYING SOLID MATERIALS OR OBJECTS BY REMOVING LIQUID THEREFROM
- F26B17/00—Machines or apparatus for drying materials in loose, plastic, or fluidised form, e.g. granules, staple fibres, with progressive movement
- F26B17/12—Machines or apparatus for drying materials in loose, plastic, or fluidised form, e.g. granules, staple fibres, with progressive movement with movement performed solely by gravity, i.e. the material moving through a substantially vertical drying enclosure, e.g. shaft
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F26—DRYING
- F26B—DRYING SOLID MATERIALS OR OBJECTS BY REMOVING LIQUID THEREFROM
- F26B25/00—Details of general application not covered by group F26B21/00 or F26B23/00
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F26—DRYING
- F26B—DRYING SOLID MATERIALS OR OBJECTS BY REMOVING LIQUID THEREFROM
- F26B25/00—Details of general application not covered by group F26B21/00 or F26B23/00
- F26B25/001—Handling, e.g. loading or unloading arrangements
- F26B25/002—Handling, e.g. loading or unloading arrangements for bulk goods
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F26—DRYING
- F26B—DRYING SOLID MATERIALS OR OBJECTS BY REMOVING LIQUID THEREFROM
- F26B3/00—Drying solid materials or objects by processes involving the application of heat
- F26B3/02—Drying solid materials or objects by processes involving the application of heat by convection, i.e. heat being conveyed from a heat source to the materials or objects to be dried by a gas or vapour, e.g. air
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Abstract
The invention discloses a moving bed drying method and a device for materials, wherein the materials are continuously updated by a heating surface unit through shunting from top to bottom by means of gravity, and the materials can be discharged out in time; the viscosity of high-moisture materials is overcome and smooth operation of the high-moisture materials is guaranteed by a heating mode that a movable heating surface with external power is arranged at the upper part or a fixed heating surface with large transverse spacing and impact gas is sprayed in; the lower heating surface is a fixed heating surface, and the evaporation steam is led out in time by arranging an evaporation steam leading-out channel in the space between the upper heating surface unit and the lower heating surface unit to improve the evaporation speed; the material is discharged from the whole section of the dryer, so that the realization of uniform material discharging from the whole section of the gravity moving bed is ensured; the emission evaporation of the bottom dry material discharge promotes the reduction of moisture and the cooling of the material, and the high-efficiency utilization of energy, the improvement of the material drying efficiency and the guarantee of the operating environment are achieved.
Description
Technical Field
The invention belongs to the technical field of drying and environmental protection, and particularly relates to a moving bed drying method and a moving bed drying device for materials such as coal, mineral powder, grains, chemical raw materials and the like, and the moving bed drying method and the moving bed drying device for the materials can be used for drying the materials and reducing the moisture.
Background
In industrial production, there are many unit processes that need to reduce the moisture content of materials, such as drying of coal, mineral powder, grain, chemical raw materials, etc., to reduce the moisture content. Among these material drying methods, there are various methods widely used in production, such as pneumatic drying, rotary tube drying, moving bed drying, and the like. However, for the material containing more fine powder and more wide particle distribution, the problems of insufficient drying of large particles and excessive drying of fine particles are easily caused due to short gas-solid contact time of airflow drying; under the conditions of large material processing amount and strong material friction, the rotary pipe drying easily causes friction and corrosion of the rotary heating pipe due to the large relative speed between the rotary pipe and the material, thereby causing the problem of high equipment cost; although the traditional moving bed can better relieve the problems of airflow drying and rotary pipe drying, the drying efficiency is often lower, especially the updating of materials and a heating surface is insufficient, the derivation of evaporation steam cannot lead to the problems of low drying efficiency in time, and the problem that the normal operation of equipment is seriously influenced by blockage and descending unsmooth materials under the condition of entering high-moisture materials is also very obvious, the problem that the uniform discharging of large-scale drying equipment directly influences the balanced discharging and normal operation of the moving bed is often caused, and the improvement of the adaptability of a dryer to materials and the uniform discharging become important problems of the stable operation of an industrial device. Therefore, the method and the device for drying the mixed material of coarse and fine particles, which are suitable for large material quantity and large material moisture change, are explored, the material and the heating surface are well updated, the export of the evaporation steam is timely, the feeding and discharging control is simple, the drying efficiency is high, and the abrasion to the equipment is small, so that the method and the device are very important for the energy conservation, environmental protection and efficiency improvement in the drying process in industrial production.
Disclosure of Invention
The invention aims to provide a moving bed drying method and a moving bed drying device for materials, wherein the materials are continuously updated by a heating surface unit through shunting from top to bottom by means of gravity, and the moving bed dryer is formed by heating plates capable of leading out evaporation steam in time, can adapt to different material moisture and uniformly discharges materials; the viscosity of high-moisture materials is overcome and smooth operation of the high-moisture materials is guaranteed by a heating mode that a movable heating surface with external power is arranged at the upper part or a fixed heating surface with large transverse spacing and impact gas is sprayed in; the lower heating surface is set as a fixed heating surface, and the projections of the adjacent heating surface units in the vertical direction are not overlapped, so that the split flow of the materials when flowing downwards is formed, the updating of the materials contacted with the heating surface is realized, and the heat exchange efficiency is improved; the evaporation steam guiding channel is arranged in the space between the upper heating surface unit and the lower heating surface unit to guide the evaporation steam in time, so that the evaporation speed is increased, and the drying efficiency is further improved; the material is discharged from the whole section of the dryer, so that the realization of uniform material discharging from the whole section of the gravity moving bed is ensured; the emission evaporation of the bottom dry material discharge promotes the reduction of moisture and the cooling of the material, and the high-efficiency utilization of energy, the improvement of the material drying efficiency and the guarantee of the operating environment are achieved. The method and the device provide effective method and device guarantee for realizing uniform drying of coarse and fine particles with large material quantity and large material moisture change, simple material feeding and discharging control, high drying efficiency and small equipment abrasion, and have the characteristics of low investment cost, simple equipment, low energy consumption and effective control of dust pollution.
The invention is realized by adopting the following technical scheme:
the moving bed drying method of the supplies, the supplies depend on gravity from moving from top to bottom and receive the indirect heating of the heat source to be divided into two parts of upper heating zone and lower drying zone, the upper heating zone close to material inlet adopts the heating mode of preventing the bridging of the supplies from blocking up, the lower drying zone far away from material inlet adopts the fixed heating mode of the fixed position of heating surface;
the upper heating zone adopts a heating mode for preventing material bridging and blocking, and adopts any mode as follows:
(1) the heating surface moves in a movable heating mode of external power, the movement is swinging or rotating or linear movement,
(2) the heating surface is fixed in position and releases impact gas to the material in the material space.
According to the method, the discharging control mechanism at the lower part of the fixed heating surface of the lower drying area discharges materials in a non-shrinkage mode with the whole discharging cross section and the same area as the heating part.
The method is characterized in that after the material is dried and discharged from the dryer, the moisture in the material is discharged as steam through the diffusion and evaporation mechanism.
The method is characterized in that the evaporated steam in the lower drying zone is used as a heat source of the upper heating zone, the evaporated steam is pumped into a heat source channel of the upper heating zone from the lower drying zone through a fan, or the evaporated steam in the lower drying zone is used as a heating heat source of the impact gas in the upper heating zone, and the impact gas before entering the dryer is heated.
The device for realizing the material drying method comprises a dryer shell, a material inlet, a movable heating surface, a fixed heating surface, an evaporation steam guide-out channel and a material discharging control mechanism; the material inlet is positioned at the upper part of the movable heating surface, the movable heating surface is positioned at the upper part of the fixed heating surface, and the material discharging control mechanism is positioned at the lower part of the fixed heating surface; the evaporation steam leading-out channel is positioned between the movable heating surface and the fixed heating surface and between the fixed heating surface layers;
the mobile heating surface and the mobile heating device thereof are any one of the following devices:
(1) the heating device for heating surface movement at least comprises a heating surface for heating materials, a heat source inlet of the heating surface, a rotating shaft rotating by means of external power, and a connecting member between the heating surface and the rotating shaft, wherein the heating surface is a circular curved surface rotating around the rotating shaft, a streamline shape with a small front end and a large rear part can be generated in the moving direction to enable the materials to be shunted to two sides, a material channel is arranged between heating surface units at the same distance from the rotating shaft, or the heating surface is a circular pipe arranged around the rotating shaft at intervals, the diameter of the circular pipe close to the rotating shaft is larger than that of the circular pipe far away from the rotating shaft,
(2) the heating device for heating surface movement at least comprises a heating surface for heating materials, a heat source inlet of the heating surface, a heat source outlet of the heating surface, a horizontal moving mechanism of the heating surface and moving power of the heating surface; the heating surface is composed of round pipes arranged at intervals.
The device for realizing the material drying method comprises a dryer shell, a material inlet, a fixed heating surface, an impact gas inlet pipe, an impact gas outlet, an evaporation steam outlet channel and a material discharging control mechanism; the material inlet is positioned at the top of the dryer, the impact gas inlet pipe is positioned between the heating surface layers at the upper part of the dryer, and the transverse distance between the heating surface layers at the upper part is larger than that between the heating surface layers at the lower part; the evaporation steam guiding channel is positioned between the fixed heating surface layers, and the material discharging control mechanism is positioned below the lower fixed heating surface.
In the device, the material discharging control mechanism at least comprises a guide plate, a guide plate rotating shaft, a guide plate rotating power transmission mechanism and a guide plate rotating power source; the guide plates are arranged in parallel at intervals on the discharging cross section and can rotate around the rotating shaft of the guide plates, the length of each guide plate is larger than that of the corresponding dryer cross section in the same direction, and the sum of the widths of the guide plates in a closed state is not smaller than that of the corresponding dryer cross section.
The device for realizing the material drying method is characterized in that a diffusion evaporation mechanism which enables moisture in the material to form steam to be discharged after the material is dried and discharged from a dryer at least comprises a material bearing inclined plate, a vibrator, a steam outlet, a material inlet and a material outlet; the inclined plate for bearing materials is arranged in a multi-section and multi-layer mode, and the included angle between the inclined plate face and the horizontal plane is 2-12 degrees.
The concrete description is as follows:
the device for drying materials comprises a dryer shell, a material inlet, a movable heating surface, a fixed heating surface, a material discharge hole control mechanism, an evaporation steam outlet and a diffusion evaporation mechanism, wherein the evaporation steam outlet is used for leading out evaporation steam generated by evaporation of water in the materials and is connected with an evaporation steam leading-out channel, and the diffusion evaporation mechanism is used for drying the materials. The material gets into the moving bed dryer from the material entry, relies on gravity from the upper portion zone of heating that the top down constitutes through removing the heating surface, then passes through the lower part drying zone that fixed heating surface constitutes downwards again, is heated the temperature by the indirect heating of heat source and risees, and the moisture that contains is evaporated, and the material obtains the material after drying and discharges from the material ejection of compact control mechanism of bottom, sends down one process after drying material gives off evaporation mechanism and discharges the evaporation steam that contains the waste heat and produce. The water vapor generated in the heating process passes through the evaporation vapor guide-out passage and is discharged out of the dryer from the evaporation vapor outlet.
The material has high moisture content and high viscosity at the upper part of the dryer, particularly, coal material agglomerates, serious adhesion phenomenon and poor fluidity if coking coal and the like with moisture of more than 11 percent are used, and if the material is directly applied to the fixed drying surface for drying, serious material bridges are easily formed and can not flow downwards; the movable heating surface is used for drying, because the heating surface is pushed by external power to form swinging, rotating or horizontal moving and other movements, bridging of materials can be well overcome through movement, downward flowing of the materials is guaranteed, the swinging can not only enable the materials to be uniformly conveyed to two directions, but also the movement and the connection mechanism are relatively simple, and the optimization can be realized. According to the research result of the inventor, the fluidity of the material is obviously improved after the material is heated and the temperature is increased; after the water content is reduced, the viscosity is greatly reduced, and the fluidity is greatly improved. The drying zone heated by the stationary heating surface is further heated to be dried. The heating of the movable heating surface at the upper part ensures that high-moisture materials flow without bridging, and the heating of the fixed heating surface at the lower part ensures low-cost high-efficiency drying. Generally, the bottom of a material dryer is provided with an inverted cone-shaped contraction section, a discharge control valve is arranged below the inverted cone-shaped contraction section, but in the inclined contraction section, the materials on the edge are supported and divided by an inclined plate, the descending power is reduced, the material flow is slowed, the distribution of the material flow speed on the cross section is uneven, the materials on the edge are further upwards conducted to cause over-drying or blockage of the materials on the edge, and the material in the central part is insufficiently heated to form a material moisture difference. Therefore, the problem of uneven material flow velocity distribution on the cross section which is easy to form in large-scale moving bed material discharging is an important technical subject and problem for ensuring the uniform drying and smooth operation of the material. The invention forms a uniform and adjustable material flow channel at the discharging position of the dryer by the guide plates which are uniformly arranged at intervals and in parallel on the whole cross section and the uniform action rotation of the guide plates, thereby well realizing the uniform and adjustable discharging of the whole cross section and ensuring the uniform drying and uniform and smooth operation of the moving bed dryer.
The material temperature that discharges from the desicator is high can produce a large amount of vapor, if undirectional discharge can distribute to around, form steam and influence environment and the follow-up transportation of material and storage, the condensation of vapor can form the water droplet, causes local coal charge humidity too big. On the other hand, if the water vapor in the material is effectively discharged, not only the temperature of the material can be reduced, which is beneficial to transportation and storage, but also the further reduction of the moisture of the material can be promoted. The invention adopts the diffusion evaporation mechanism to form an evaporation space, promotes the loosening and surface updating of the material while conveying the material on the vibrating inclined plate, accelerates the evaporation of water in the material layer and the cooling of the material, and efficiently realizes the further drying, cooling and material conveying.
The movement of the moving heating surface can be a rotation around a rotation axis (in a specific manner, it can be an oscillation or a rotation), or a transverse movement on the cross section of the dryer. The coal can be evenly fed in a swinging mode, and the coal feeding device is more convenient to connect with a heat source. The rotary moving heating surface adopts a circular curved surface rotating around the rotating shaft, so that the rotating resistance of the heating surface can be minimized, and a streamline shape which enables the material to be shunted to two sides and has a small front end and a large rear part can be generated in the moving direction, so that the blocking effect of the material is dispersed, and the resistance of the material to the rotation of the heating surface is reduced; and a material channel is arranged between the heating surface units at the same distance from the rotating shaft, so that the movement of the material and the updating of a heating interface are promoted. The heating surface can also be composed of round tubes arranged at intervals around the rotating shaft, the diameter of the round tube close to the rotating shaft is larger than that of the round tube far from the rotating shaft, so that the linear velocity of the round tube far from the rotating shaft is large, and the resistance formed by the resistance is reduced by the characteristic that small resistance is generated by small diameter. The heating surface adopting the transverse moving mode can be more convenient by a heating surface consisting of round pipes arranged at intervals.
In the fixed heating surface heating area, fixed heating surfaces are arranged at intervals in the transverse direction; the heating surfaces are arranged perpendicular to the horizontal plane, material particles flow through the space between the heating surfaces, and heating plates arranged at intervals in the transverse direction form heating surface units (in the transverse direction of the dryer, a non-contact area exists between the heating surfaces). A plurality of heating surface units are arranged at intervals in the longitudinal direction (one non-contact area exists between the heating surface units on the transverse projection surface of the dryer), and the heating plates of the heating surface units adjacent to each other up and down do not overlap on the projection surface in plan view. Thus, the material moves downward by gravity, through one heating surface element and into the next heating surface element. Because the heating plates of the heating surface units adjacent to each other up and down are not overlapped on the overlooking projection surface, when a material enters the next heating surface unit, the heating plates can play a role in shunting the material, so that the material in the upper layer of heating surface unit, which is contacted with the heating surface, enters the material flow, and the material in the material flow is contacted with the next layer of heating surface unit when the upper layer of heating surface unit is contacted with the next layer of heating surface unit and is directly heated, thereby updating the heating interface of the material and promoting the heat transfer between the heating surface and the material. Therefore, the materials are continuously updated along with descending in the dryer, the heat transfer effect is greatly improved, the materials are efficiently heated in the descending process, and the contained water is evaporated and dried. In practical engineering, it is difficult to vertically arrange the heating surface at a strict 90 ° with respect to the horizontal plane, and the heating surface can be considered to be vertically arranged with respect to the horizontal plane as long as the included angle between the heating plate and the horizontal plane is within 90 ° ± 10 °.
The material is heated by the heat source when passing through the heating surface unit in the descending process, the temperature rises, the moisture is evaporated to generate evaporation steam, and the volume of the water is increased sharply after the water is changed into the steam, and the water needs to be led out from the dryer in time. The space between the upper heating surface unit and the lower heating surface unit is provided with the evaporation steam guide-out channel, so that the evaporation steam generated by evaporation can be timely discharged out of the dryer from the evaporation steam outlet through the guide-out channel, and the smooth and efficient proceeding of heat transfer and material flowing in the dryer is guaranteed. The evaporation steam outlet channel can be arranged at the lower end of the heating surface and also can be arranged at the upper end of the heating surface. And may be disposed at an appropriate position between the upper and lower heating surface units according to the drying object and the heat source.
The evaporation steam outlet channel arranged between the heating surface units is provided with an opening for entering evaporation steam at the lower part, the upper part of the evaporation steam outlet channel is closed, and materials cannot enter the evaporation steam outlet channel from the upper part. The shape of the evaporation steam channel can be a simple bevel edge shape or an arc, as long as a guide channel of the evaporation steam can be formed and the inflow of materials is prevented. The evaporation steam outlet channel can be formed by independently arranging one layer or overlapping two layers, and a gap for the evaporation steam to enter is reserved between the two layers; the lower part of the single-layer arrangement needs to be wider, and the width of the lower part of the channel can be reduced by the double-layer arrangement, so that the bridging is prevented.
Because the evaporation steam lead-out channel is arranged between the heating surface units, the material moving from top to bottom can be divided, even if the heating plates of the heating surface units adjacent to each other up and down are overlapped on the overlooking projection surface, the evaporation steam lead-out channel can substantially divide the material, and the heating interface of the material can be updated when the material flows through the heating surface units. However, the heating plates of the heating surface units adjacent to each other up and down are not overlapped on the overlooked projection surface, and can pass through the double shunting of the evaporation steam outlet channel and the heating plates, so that the updating effect of the heating interface is better. Therefore, in actual engineering, it is preferable that the heating plates of the heating surface units adjacent to each other vertically are arranged so as not to overlap each other in a plan view projection plane.
The heating surface generally adopts a jacket plate type structure with a heat source introduced therein, and the inner surface of the heating surface is provided with an inner surface metal rib vertical to the inner surface of the jacket, so that the rigidity of the jacket heating surface can be greatly enhanced, the heating surface is prevented from bulging outwards due to the pressure of the heat source introduced therein, the outer surface of the heating plate is kept flat, and the smooth flowing of materials is ensured.
The material discharging control mechanism drives the guide plate to rotate around the guide plate rotating shaft through the guide plate rotating power source and the guide plate rotating power transmission mechanism, and the opening and closing of the material discharging control mechanism and the discharging speed of the material discharging control mechanism are achieved. A plurality of guide plates are arranged on the discharge cross section at intervals in parallel, and the space between the guide plates forms a passage for the downward flow of materials; when the guide plate is in a downward vertical state, the material discharging control mechanism is equivalently fully opened, and the maximum discharging speed is achieved; when the included angle omega between the guide plate and the horizontal plane is reduced, the guide plate is influenced by the fact that the acting force of the guide plate is increased when the guide plate falls, the spacing distance between the guide plates is reduced, the flow of the materials passing through is reduced, and therefore the discharging flow of the materials can be adjusted by adjusting the included angle omega between the guide plate and the horizontal plane; when the material guide plate inclines to a certain angle and omega is smaller than the sliding angle of the material on the flat plate, the material can not flow any more, and the material discharging control mechanism is closed. The length of the guide plate is larger than the length corresponding to the cross section of the dryer in the same direction, and the sum of the widths of the plates when the guide plate is in a closed state is not smaller than the size corresponding to the cross section of the dryer, so that the guide plate can control the flow of materials on the cross section of the dryer, and the materials can not overflow transversely.
For materials with high moisture content and high viscosity, the material bridging can be overcome in the upper heating zone of the dryer by arranging fixed heating plates with large transverse spacing in the upper heating zone of the moving bed and introducing impact gas capable of generating impact action in the material interval between the heating plate layers. When the materials form a bridge, the impact gas is introduced to generate impact force on the material bridge to damage the material bridge, so that the downward movement of the materials is ensured. The impact gas is compressed air and is jetted out through an impact gas inlet pipe arranged in the material space and an impact gas jet hole formed in the impact gas inlet pipe, and the impact gas jet hole can be arranged to be a downward hole in order to prevent the material from entering the pipeline through the jet hole. The compressed air can be air at atmospheric temperature or heated hot air, and the hot air can also play a role in heating the material while breaking the bridge. In addition, the height of the heating surface of the upper heating area is lower than that of the heating surface of the lower drying area, so that the function of bridging of materials can be reduced.
The material temperature of the lower drying zone is high, the material temperature of the upper heating zone is low, the energy-saving effect can be achieved by using the evaporated steam of the lower drying zone as a heat source of the upper heating zone, the evaporated steam can be pumped into a heat source channel of the upper heating zone from the lower drying zone through a fan, and the evaporated steam can be pumped into the heat source channel of the upper heating zone from an outlet of the heat source channel of the upper heating zone or pumped into the heat source channel of the upper heating zone from an inlet of the heat source channel of the upper heating zone. The evaporated steam extracted from the lower drying zone is passed through a dust-removing device to remove the contained particles before entering the heat source channel of the upper heating zone, so as to prevent the particles from depositing in the heat source channel of the upper heating zone and forming blockage. The evaporated steam in the lower drying zone can also be used as a heating source of the impact gas in the upper heating zone to heat the impact gas before entering the heater, and the impact gas can also heat and take away the moisture in the material while preventing the material from bridging, so that the purpose of energy conservation is achieved. In the practical engineering, the evaporated steam in the lower drying area can be used as the heat source of any fixed heating plate at the upper part of the dryer, so that the energy-saving effect is further improved.
The invention has the beneficial effects that:
the heating mode and the dryer structure can adapt to moving beds with different material moisture and uniform discharging; the viscosity of high-moisture materials is overcome and smooth operation of the high-moisture materials is guaranteed by a heating mode that a movable heating surface with external power is arranged at the upper part or a fixed heating surface with large transverse spacing and impact gas is sprayed in; the heating surface of the lower drying area is set as a fixed heating surface, and the projections of the adjacent heating surface units in the vertical direction are not overlapped, so that the split flow of the materials in the downward flow is formed, the updating of the materials in contact with the heating surface is realized, and the heat exchange efficiency is improved; the evaporation steam guiding channel is arranged in the space between the upper heating surface unit and the lower heating surface unit to guide the evaporation steam in time, so that the evaporation speed is increased, and the drying efficiency is further improved; the material is discharged from the whole cross section of the dryer, so that the realization of uniform material discharging from the whole cross section of the gravity moving bed is ensured; the vibration evaporation of the discharged dry material at the bottom promotes the reduction of moisture and the cooling of the material, so that the high-efficiency utilization of energy, the improvement of the drying efficiency of the material and the guarantee of the operating environment are achieved; the evaporated steam in the lower drying zone is used as a material heating heat source in the upper heating zone or a heating heat source of the impact gas, so that the multi-effect utilization of the heat source is realized, and the aim of saving energy is fulfilled. The method and the device provide effective method and device guarantee for realizing uniform drying of coarse and fine particles with large material quantity and large material moisture change, simple material feeding and discharging control, high drying efficiency and small equipment abrasion, and have the characteristics of low investment cost, simple equipment, low energy consumption and effective control of dust pollution.
Drawings
FIG. 1: the upper moving heating surface heats the front schematic view of the material dryer with the lower fixed heating surface heating moving bed;
FIG. 2: a schematic side view of a material dryer with an upper moving heating surface for heating and a lower fixed heating surface for heating a moving bed;
FIG. 3: a schematic front view of a heating device with a circumferential curved surface moving heating surface;
FIG. 4: a schematic side view of a heating device with a circumferential curved surface moving heating surface;
FIG. 5: the front schematic view of the heating device with the circular tube moving heating surface;
FIG. 6: schematic side view of the heating device with round tube moving heating surface;
FIG. 7: the front schematic diagram of the material dryer with a large-space heating surface and a small-space fixed heating surface, wherein the upper part of the material dryer is provided with impact gas to heat the material dryer;
FIG. 8: a schematic side view of a material dryer with a large-space heating surface and a small-space fixed heating surface, wherein the upper part of the material dryer is provided with impact gas to heat the material dryer;
FIG. 9: a schematic view of a structure of the impact gas introduction pipe;
FIG. 10: the structure schematic diagram of the material discharging control mechanism;
FIG. 11: the structure A-A of the material discharging control mechanism is schematic;
wherein: 1-material, 2-dryer shell, 3-material inlet, 4-moving heating surface, 5-fixed heating surface, 5 a-transverse large-interval fixed heating surface, 6 a-fixed heating surface material channel a,6 b-fixed heating surface material channel b, 7-evaporation steam outlet channel, 8-material discharge control mechanism, 9-dried material emission evaporation mechanism, 10-material outlet, 11-moving heating surface rotating shaft, 12-moving heating surface heat source inlet, 13-moving heating surface heat source outlet, 14-evaporation steam outlet, 15-fixed heating surface heat source inlet, 16-fixed heating surface heat source outlet, 17-circumferential curved heating surface, 18-moving heating surface moving front end streamline tip, 19-moving heating surface material channel, 20-connecting a moving heating surface and a rotating shaft, 21-swinging direction of the moving heating surface, 22-heating pipe with large diameter near the rotating shaft, 22-heating pipe with small diameter far from the rotating shaft, 23-impact gas inlet pipe, 24-impact gas outlet, 25-impact gas outlet, 26-guide plate rotating power source, 27-guide plate rotating power transmission mechanism, 28-guide plate, 29-guide plate rotating shaft, B-transverse distance of upper heating plates, B-transverse distance of lower heating plates, included angle between a beta-vibrating plate and a horizontal plane, and included angle between an omega-guide plate and the horizontal plane.
For a person skilled in the art, other relevant figures can be obtained from the above figures without inventive effort.
Detailed Description
In order to make the technical solution of the present invention better understood, the technical solution of the present invention is further described below with reference to specific examples.
Example 1
This example is an embodiment of a method and apparatus for drying coking coal by heating with an upper moving heating surface and a lower fixed heating surface and a moving bed with a fixed heating surface.
As shown in the figures 1 and 2, a material (coking coal material) 1 enters the dryer from a material inlet 3 arranged on a dryer shell 2 and moves from top to bottom by gravity, the material is heated and heated by a movable heating surface 4 and then enters a fixed heating surface 5 to be further heated, generated evaporation steam is discharged out of the dryer through an evaporation steam outlet 7 and an evaporation steam outlet 14, the moisture of the coal material is reduced, the generated evaporation steam finally flows out of the dryer through a material discharging control mechanism 8 and enters a drying material diffusion evaporation mechanism 9, the contained heat promotes the moisture in the coal material to be further evaporated, the temperature of the coal material is reduced, and finally the coal material is sent into a coal material conveying system (not shown in the figures) from a material outlet 10 to enter a coal bunker for coal charging.
The heating of the moving heating surface adopts the structure as shown in fig. 3 and 4, the moving of the moving heating surface is realized by a swinging mode, the rotating shaft 11 is driven to rotate by external power (not marked in the figure), so that the circumferential curved surface heating surface 17 and the moving front end streamline-shaped tip 18 of the moving heating surface do reciprocating motion along the swinging direction 21, and the coal material moves through the material channel 19 and is contacted with the heating surface to be heated. The swinging movable heating surface consists of a circumferential curved surface heating surface 17 and a streamline tip 18 at the moving front end of the movable heating surface, and the circumferential curved surface and the streamline tip greatly reduce the moving resistance of the heating surface; the maximum angle of oscillation is 15 °. The number of heating surfaces can be determined according to the size of the equipment.
The coal material moves downwards to enter the material channel 6a after entering the fixed heating surface area and then enters the heating surface unit material channel 6b, and is further heated by gravity descending, the evaporation steam generated by the evaporation of the moisture contained in the material enters the evaporation steam channel 7 and is led out of the system through the evaporation steam outlet 14, and the moisture in the material is evaporated and reduced. The heating heat source enters a heat source channel in the heating plate from a heat source inlet 15, and the material is dried by the heating plate and then is discharged out of the drying system from a heat source outlet 16.
The movable heating surface and the fixed heating surface are both jacket type heating plates with heat source channels inside. The fixed heating surface 5 is arranged at a right angle with the horizontal plane, a plurality of heating surfaces which are transversely arranged at intervals form a heating surface unit, an interval space between the heating surfaces forms a heating surface unit material channel, and the heating surface unit material channel 6a and the heating surface unit material channel 6b are arranged in sequence from top to bottom; the heating plates of the adjacent heating surface units are arranged crosswise in the transverse direction, namely the heating plates of the heating surface units adjacent up and down do not overlap on the overlooking projection surface. Therefore, the material is divided in the descending process, so that the material in the upper layer of heating surface units in contact with the heating surface enters the material flow, and the material in the material flow in the upper layer of heating surface units is in contact with the next layer of heating surface units and is directly heated, the heating interface of the material is updated, and the heat transfer between the heating surface and the material is promoted.
The heat source adopts steam, and the gauge pressure is 0.5 MPa. Because the fixed heating surface is in a plate-shaped structure, the heating plate can deform under the pressure of an internal heat source, and therefore, reinforcing ribs are added on the inner side of the heating surface of the jacket. Therefore, the flowing of the coal materials is not influenced, the rigidity of the heating surface of the jacket can be greatly enhanced, the heating surface is prevented from bulging outwards due to the pressure of a heat source introduced into the heating surface, and the smooth flowing of the materials is ensured.
The evaporated steam in the lower drying zone is pumped out by a fan and then is forced to be introduced into a heat source channel of the upper heating zone to be used as a material heating heat source (not shown in the figure), and the evaporated steam enters the fan after fine coal particles contained in the steam are removed by a dust remover before entering the fan.
The material discharging control mechanism 8 is shown in fig. 10, coal material flows downwards through the space between the guide plates 28, and is discharged from the dryer, and the space between the guide plates is 200 mm. The guide plate 28 is driven by the guide plate rotating power source 26 and the guide plate rotating power transmission mechanism 27 to rotate around the guide plate rotating shaft 29, so that an adjustable angle with omega of 10-25 degrees is formed, and the material discharging speed is controlled. The length of the guide plate is 60mm longer than that of each side of the cross section of the dryer in the same direction, and the sum of the widths of the plates when the guide plate is in a closed state is equal to the corresponding size of the cross section of the dryer, so that the guide plate can control the flow of materials on the cross section of the dryer, and the materials cannot overflow transversely.
The drying material emission evaporation mechanism 9 is composed of an upper layer of vibration plate and a lower layer of vibration plate, the upper layer and the lower layer of vibration plate are inclined towards different directions respectively, an included angle beta between each vibration plate and a horizontal plane is adjustable between 2 degrees and 12 degrees, and the amount of the drying material emission evaporation mechanism is determined according to the vibration amplitude and the discharge amount. The upper vibrating plate is composed of a plurality of non-integral sub-plates, and coal can fall down in the space between the sub-plates. The coal material falls from the discharging control mechanism to the upper layer vibration plate, moves forwards while jumping up and down under the vibration action, continues to move in different directions in jumping after falling to the lower layer vibration plate, and is finally discharged from the material outlet 10. A space for steam to move is arranged above the coal material on the vibrating plate, water is evaporated in the vibrating and moving processes, the temperature of the material is reduced from 85 ℃ to below 50 ℃, and the water is further reduced. The evaporated water vapour is drawn off by a suction fan (not shown). The vibration mode is a vibration motor (not shown) commonly used in industry.
The coal material is dried from 11.5% to 8% in moisture and little dust is carried over with the evaporated steam.
An external power movable heating surface is arranged at the upper part of the moving bed dryer, so that the viscosity of high-moisture materials is overcome, bridging is prevented, and smooth operation of the high-moisture materials is guaranteed; the materials formed between the heating surface units are fixed and divided, so that the materials in contact with the heating surface are updated, and the heat exchange efficiency is improved; the evaporation steam is led out in time through the evaporation steam leading-out channel arranged below the upper heating surface unit and the lower heating surface unit, so that the evaporation speed is increased, and the drying efficiency is further improved; the use of the heat source steam is reduced by using the evaporated steam from the lower drying zone as the heat source for the upper heating zone.
Example 2
This example is essentially the same as example 1, except that the dried material is lignite, dried from 30% moisture to 15%. The heat source is heat conducting oil, the inlet of the heat source is 200 ℃, and the outlet of the heat source is 150 ℃.
The upper part of the dryer adopts a moving heating surface consisting of round pipes, and the structure is shown in fig. 5 and 6. The diameter of the tube close to the rotating shaft is phi 60, the middle is phi 48, the outer edge is phi 32, the moving heating surface of the tube moves in a swinging mode, and the maximum swinging angle is 20 degrees. The movable heating surface is overlapped by the upper unit and the lower unit, so that a movable heating area is increased, the movable heating surface is suitable for high moisture of lignite, and bridging is prevented. And an evaporation steam outlet channel is arranged between the two moving pipe heating units to promote the evaporation.
The evaporated steam in the lower drying zone is pumped into a heat source channel of the upper heating zone by a fan to be used as a material heating heat source (not shown in the figure), the fan is arranged at the outlet of the heat source channel of the upper heating zone, and the evaporated steam is removed from fine coal particles contained in the steam by a dust remover before entering the heat source channel of the upper heating zone.
The lignite is easy to bridge due to high moisture, the bridge of the lignite is effectively prevented and eliminated through the swinging circular tube heating surface, and the fixed heating surface is longer than the distance between the heating surfaces of the device used in the embodiment 1.
Example 3
This example is substantially the same as example 1, except that the dried product was flour, and the moisture content was 13% to 8%. The moving of the heating surface is realized in a rotating mode.
Example 4
This example is essentially the same as example 1, with the different moving heating surfaces being realized in a manner that they move transversely across the cross-section of the dryer.
Example 5
This example is an embodiment of a moving bed coking coal drying method and apparatus in which the upper heating zone employs a large transverse spacing, impingement gas introduction tubes are disposed between heating surface layers, and the lower fixed heating surface is heated and dried.
The dryer is as shown in fig. 7 and 8, a material (coking coal) 1 enters the dryer from a material inlet 3 arranged on a dryer shell 2 and moves from top to bottom by gravity, the material is heated and heated by a transverse large-interval heating surface 5a and then enters a fixed heating surface 5 to be further heated, generated evaporation steam is discharged out of the dryer through an evaporation steam outlet 7 and an evaporation steam outlet 14, the moisture of the coal is reduced, the material finally flows out of the dryer through a material discharging control mechanism 8 and enters a drying material diffusion evaporation mechanism 9, the contained heat promotes the moisture in the coal to be further evaporated, the temperature of the coal is reduced, and finally the coal is sent into a coal conveying system (not shown in the figure) from a material outlet 10 and enters a coal bunker for coal charging.
The lateral spacing B of the lateral large-spacing heating surfaces 5a of the upper heating zone was 500mm, and the lateral spacing B of the fixed heating surfaces 5 of the lower drying zone was 300 mm. The upper heating zone is provided with an impingement gas introduction tube 23, and impingement gas ejection holes 25 are provided at the lower circumference of the tube, as shown in fig. 9. The impact gas is compressed air (not shown in the figure) heated to 80 ℃, and is discharged from the impact gas outlet 24 after the coal material bridging prevention impact effect is completed.
The coal material moves downwards to enter a lower drying area of the fixed heating surface and then enters a material channel 6, the coal material is further heated by falling under the action of gravity, evaporation steam generated by evaporation of moisture contained in the coal material enters an evaporation steam channel 7 and is led out of the system through an evaporation steam outlet 14, and the moisture in the coal material is evaporated and reduced. The heating heat source enters a heat source channel in the heating plate from a heat source inlet 15, and the material is dried by the heating plate and then is discharged out of the drying system from a heat source outlet 16. The heating plate of the lower drying zone was arranged in the same manner as in example 1.
The evaporated steam in the lower drying zone is pumped out by a fan and then is pressure-fed into a heat source channel of the upper heating zone to be used as a material heating heat source, and the evaporated steam enters the fan after fine coal particles contained in the steam are removed by a dust remover before entering the fan.
The coal material is dried from 11.5% to 8% in moisture and little dust is carried over with the evaporated steam.
The upper heating zone of the moving bed dryer is provided with the transverse large-interval heating surface and the bridging impact-resistant gas guide pipe, so that the viscosity of high-moisture materials is overcome, bridging is prevented, and smooth operation of the high-moisture materials is guaranteed; the material formed between the heating surface units is fixed in the lower drying area to be shunted, so that the material contacted with the heating surface is updated, and the heat exchange efficiency is improved; the evaporation steam is led out in time through the evaporation steam leading-out channel arranged below the upper heating surface unit and the lower heating surface unit, so that the evaporation speed is increased, and the drying efficiency is further improved; the use of the heat source steam is reduced by using the evaporated steam from the lower drying zone as the heat source for the upper heating zone.
Example 6
This example is substantially the same as example 5, except that the evaporated steam in the lower drying zone is pumped out by a fan and then is pressure-fed into a heat source channel of the upper heating zone to be used as a material heating heat source, and the evaporated steam enters the fan after fine coal particles contained in the steam are removed by a dust remover before entering the fan. Meanwhile, the evaporated steam in the lower drying zone is pumped out by a fan and then sent to a heating system of the impact gas for the upper heating zone to be used as a heating source of the impact gas.
The invention has been described in an illustrative manner, and it is to be understood that any simple variations, modifications or other equivalent changes which can be made by one skilled in the art without departing from the spirit of the invention fall within the scope of the invention.
Claims (5)
1. A moving bed drying method of materials is characterized in that the materials move from top to bottom by means of gravity and are indirectly heated by a heat source, the drying process is divided into an upper heating area and a lower drying area, the upper heating area close to a material inlet adopts a heating mode for preventing bridging of the materials, and the lower drying area far away from the material inlet adopts a fixed heating mode with a fixed heating surface;
the upper heating zone adopts a heating mode for preventing material bridging and blocking, and adopts one of the following two modes:
(1) the heating surface moves in a movable heating mode by external power, and the movement is rotation; the drying device formed by the method at least comprises a dryer shell, a material inlet, a movable heating surface, a fixed heating surface, an evaporated steam guiding channel and a material discharging control mechanism; the material inlet is positioned at the upper part of the movable heating surface, the movable heating surface is positioned at the upper part of the fixed heating surface, and the material discharging control mechanism is positioned at the lower part of the fixed heating surface; the evaporation steam leading-out channel is positioned between the movable heating surface and the fixed heating surface and between the fixed heating surface layers; the heating device for moving the heating surface at least comprises a heating surface for heating materials, a heat source inlet of the heating surface, a rotating shaft rotating by means of external power, and a connecting member between the heating surface and the rotating shaft, wherein the heating surface is a circular curved surface rotating around the rotating shaft, a streamline shape with a small front end and a large rear part and capable of shunting the materials to two sides can be generated in the moving direction, a material channel is arranged between heating surface units at the same distance from the rotating shaft, or the heating surface is formed by round pipes rotating around the rotating shaft and arranged at intervals, and the diameter of the round pipe close to the rotating shaft is larger than that of the round pipe far away from the rotating shaft;
(2) the position of the heating surface is fixed, and impact gas is released to the material in the material space of the heating surface; the drying device formed by the method at least comprises a dryer shell, a material inlet, a fixed heating surface, an impact gas inlet pipe, an impact gas outlet, an evaporation steam outlet channel and a material discharging control mechanism; the material inlet is positioned at the top of the dryer shell, the impact gas inlet pipe is positioned between the fixed heating surface layers at the upper part of the dryer shell, and the transverse distance between the upper fixed heating surfaces is larger than that between the lower fixed heating surfaces; the evaporation steam leading-out channel is positioned between the fixed heating surface layers, and the material discharging control mechanism is positioned below the lower fixed heating surface;
the material discharging control mechanism at least comprises a guide plate, a guide plate rotating shaft, a guide plate rotating power transmission mechanism and a guide plate rotating power source; a plurality of guide plates are arranged on the discharging cross section at intervals in parallel and can rotate around the rotating shaft of the guide plate, and the length of each guide plate is larger than that of the corresponding cross section of the dryer shell in the same direction.
2. A method for moving bed drying of materials according to claim 1, wherein the material discharge control means at the lower part of the fixed heating surface of the lower drying zone discharges in a non-shrinking type manner having a full cross-section of the discharge equal to the area of the heating part.
3. A method for drying a material moving bed according to claim 1, wherein after the material is discharged from the drying apparatus after the drying is completed, the moisture in the material is discharged as steam by means of a transpiration evaporation mechanism.
4. A method for moving bed drying of material according to claim 1, wherein the evaporated steam from the lower drying zone is used as a heat source for the upper heating zone, and the evaporated steam is pumped by a fan from the lower drying zone into the heat source channel of the upper heating zone, or the evaporated steam from the lower drying zone is used as a heat source for the impingement gas of the upper heating zone, and the impingement gas is heated before entering the drying apparatus.
5. A method for moving bed drying of material as defined in claim 3 wherein the emanation-evaporation mechanism is comprised of at least a sloped plate carrying the material, a vibrator, a steam outlet, a second material inlet and a second material outlet; the inclined plate for bearing the materials is arranged in a multi-section and multi-layer mode, and the included angle between the plate surface of the inclined plate and the horizontal plane is 2-12 degrees.
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| CN113551511B (en) * | 2021-07-28 | 2023-09-15 | 天津大学 | Material heating and dewatering method and device |
| CN113606872B (en) * | 2021-08-02 | 2022-06-21 | 农业农村部南京农业机械化研究所 | Fluidized bed dryer based on graphene far-infrared heating and drying method thereof |
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20030030091A (en) * | 2001-10-08 | 2003-04-18 | 주식회사 한성플랜트 | Evaperation degreasing machine |
| CN101303146A (en) * | 2008-01-24 | 2008-11-12 | 郑州阿波罗肥业有限公司 | Air cooling device and novel process for cooling high tower granulation fertilizer |
| CN203207080U (en) * | 2013-03-14 | 2013-09-25 | 牧羊有限公司 | Down-flow and counter-flow grain drying tower |
| CN204944092U (en) * | 2015-07-03 | 2016-01-06 | 无锡市稼宝药业有限公司 | Vertical revolving drying machine |
| CN110118483A (en) * | 2019-04-02 | 2019-08-13 | 天津大学 | The drying means and device of material |
-
2019
- 2019-11-13 CN CN201911108592.8A patent/CN110926111B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20030030091A (en) * | 2001-10-08 | 2003-04-18 | 주식회사 한성플랜트 | Evaperation degreasing machine |
| CN101303146A (en) * | 2008-01-24 | 2008-11-12 | 郑州阿波罗肥业有限公司 | Air cooling device and novel process for cooling high tower granulation fertilizer |
| CN203207080U (en) * | 2013-03-14 | 2013-09-25 | 牧羊有限公司 | Down-flow and counter-flow grain drying tower |
| CN204944092U (en) * | 2015-07-03 | 2016-01-06 | 无锡市稼宝药业有限公司 | Vertical revolving drying machine |
| CN110118483A (en) * | 2019-04-02 | 2019-08-13 | 天津大学 | The drying means and device of material |
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