JP7253288B1 - rotary drying furnace - Google Patents

Abstract

A simple rotary drying furnace for drying an object to be dried is provided. A furnace body (1) having at least one furnace segment (11) that can be connected in series; a frame (2) that rotatably houses the furnace body; a hot air generator 5 that circulates hot air toward the side; an object-to-be-dried input device 3 that is provided on the upstream side of the furnace body and feeds the object to be dried from the upstream end of the furnace body; and rotates the furnace body. The furnace split body is configured by connecting rectangular plate-shaped furnace wall elements in the circumferential direction so that the cross section of the furnace split body is an even-numbered polygon. The interior of the furnace split body is divided into two along the axial direction by a partition plate element, and the partition plate element has a flat plate and feed plates provided on the front and back sides of the flat plate at a predetermined pitch. provided inclined with respect to the axial center of the furnace split so that the drying object can be moved downstream by the rotation of the split furnace. [Selection drawing] Fig. 1

Description

The present invention relates to a rotary drying furnace for drying food residues and food waste discarded from food processing factories.

Conventionally, food residue and food waste discarded from food processing plants have been transported to a disposal site, dried, reused as fertilizer, and processed by incineration.

Food waste, on the other hand, contains a lot of water and is expensive to transport. Alternatively, there are problems such as the fact that there are many raw materials that are easily perishable, emit offensive odors, and are difficult to store.

Japanese Patent No. 5391492 JP 2012-117681 A

The present invention provides a simple rotary drying furnace for drying objects to be dried.

The present invention comprises a furnace body having at least one furnace segment that can be connected in series, a frame for rotatably housing the furnace body, and a furnace body provided downstream of the furnace body and extending upstream into the furnace. a hot air generator that circulates hot air through the furnace; an object-to-be-dried loading device that is provided upstream of the furnace body and loads the object to be dried from the upstream end of the furnace; and a drive unit that rotates the furnace. The furnace split is constructed by connecting rectangular plate-shaped furnace wall elements in the circumferential direction so that the cross section of the furnace split is an even-numbered polygon. The partition plate element is divided into two along the axial direction, and has a flat plate and feed plates provided on the front and back sides of the flat plate at a predetermined pitch. The present invention relates to a rotary drying furnace which is inclined with respect to the axis of the divided furnace so as to move the object to be dried downstream.

The present invention further comprises a heat exchanger, the hot air generator heats and blows outside air sucked through the heat exchanger, and the exhaust gas discharged from the upstream end of the furnace body is discharged through an exhaust duct. The present invention relates to a rotary drying furnace configured to be led to the heat exchanger, exchange heat with the outside air in the heat exchanger, and then be discharged.

Furthermore, in the present invention, the hot air generator is provided in the furnace body via a discharge chute, the discharge chute has a damper at the discharge port, and the drying object loading device stores the drying objects. It has a hopper and a screw conveyor that cuts out the material to be dried from the hopper and discharges it to the upstream end of the furnace body, and the damper is closed when the rotation of the furnace body is stopped or the screw conveyor is stopped. It relates to a rotary drying furnace having a similar configuration.

According to the present invention, a furnace body having at least one furnace split body that can be connected in series; a frame for rotatably housing the furnace body; a hot air generator that circulates hot air toward the furnace body, a drying object input device that is provided on the upstream side of the furnace body and loads the drying object from the upstream end of the furnace body, and a drive unit that rotates the furnace body The furnace segment is configured by connecting rectangular plate-shaped furnace wall elements in the circumferential direction so that the cross section of the furnace segment is an even-numbered polygon, and the interior of the furnace segment is a partition plate The partition plate element has a flat plate and feed plates provided on the front and back of the flat plate at a predetermined pitch. In order to move the object to be dried downstream, the furnace body is inclined with respect to the axial center of the furnace body, so that the furnace body can have a simple structure, and can be manufactured easily and at a low manufacturing cost. A desired number of separate furnace bodies can be connected, so that the required processing capacity can be easily met.

1 is a schematic diagram of a rotary drying furnace according to an embodiment of the present invention; FIG. FIG. 2 is a side view of a furnace body of the rotary drying furnace and a furnace body support frame that supports the furnace body; It is a cross-sectional view of the furnace body. It is a side view of a furnace split body. FIG. 4 is a schematic perspective view of a furnace wall element that constitutes a furnace split body; (A) is an explanatory view of a connecting portion between furnace wall elements, and (B) is an explanatory view of another connecting portion between furnace wall elements. Fig. 3 is a plan view of the partition plate element; FIG. 10 is a side view of a divider element; (A) is a plan view of a partition plate configured by connecting partition plate elements, and (B) is a front and back view of the partition plate. It is explanatory drawing which shows the relationship between a furnace body, a drying chamber, and an object to be dried. (A), (B), (C), (D), (E), and (F) are explanatory diagrams showing the behavior of the object to be dried when the furnace body rotates. FIG. 4 is a schematic diagram of a rotary drying furnace according to another embodiment of the present invention;

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 shows a schematic configuration diagram of a rotary drying furnace according to this embodiment.

In FIG. 1, 1 is a hollow cylindrical furnace body, 2 is a frame for rotatably housing the furnace body 1, 3 is a drying object loading device for loading the drying object into the furnace body 1, and 4 is A motor that rotates the furnace body 1, a hot air generator 5 that is provided at the downstream end of the furnace body 1 and blows hot air into the furnace body 1, and a heat exchanger 6 that recovers waste heat from exhaust gas. 7 is a discharge chute provided between the downstream end of the furnace body 1 and the hot air generator 5; is shown.

While the furnace body 1 is being rotated at a constant speed by the motor 4 , the food waste as the material to be dried is put into the upstream end of the furnace body 1 by the material to be dried introduction device 3 . The rotation of the furnace body 1 moves the food waste downstream.

The hot air generator 5 has a heat source such as a heater and a blower, sucks outside air through the heat exchanger 6, raises the temperature of the outside air with the heat exchanger 6, heats it with the heat source, Hot air is generated and blown so as to circulate from the downstream end to the upstream end inside the furnace body 1 . The temperature of the hot air should be a temperature at which the food waste will not ignite when dried, for example, about 100°C.

The hot air flows upstream inside the furnace body 1, is discharged from the upstream end as exhaust gas, and is guided to the heat exchanger 6 by a duct or the like. The heat exchanger 6 exchanges heat between the exhaust gas and the outside air, and the exhaust gas whose temperature has been lowered to a predetermined temperature is discharged outside the rotary drying furnace.

Food waste is heated by hot air in the process of moving downstream in the furnace body 1, dried, and discharged out of the furnace through the discharge chute 7. As shown in FIG.

Next, the furnace body 1 will be described with reference to FIGS. 2 to 4. FIG.

The furnace body 1 is composed of a plurality of furnace segments 11 having the same structure, and the furnace body 1 is constructed by connecting the furnace segments 11 on the same axis.

As the material for the furnace body 1 and the furnace segment 11, since the temperature inside the furnace is as low as about 100° C., general iron-based materials can be used.

The number of continuous furnace divisions 11 is selected according to the required amount of food waste. In the embodiment shown in FIG. 1, four furnace split bodies 11 are arranged in series.

The furnace segment 11 has a furnace wall 12 and end plates 13 and 14 provided concentrically with the furnace wall 11 at both ends of the furnace wall 12 .

The cross section of the furnace wall 12 is an even number of polygons, and this embodiment shows the case of an octagon. The even-numbered polygon may be a regular polygon or may not be a regular polygon. However, the polygon must be symmetrical about two orthogonal axes passing through its center.

Each side of the polygon is composed of a rectangular plate-shaped furnace wall element 15 having the same structure. As shown in FIG. 5, the furnace wall element 15 has a basic structure in which flat metal plates are bent or welded together. Incidentally, the furnace wall element 15 may be appropriately provided with a reinforcing material in order to replenish its strength.

The furnace wall 12 is configured by arranging the furnace wall elements 15 on each side of a polygon and connecting the furnace wall elements 15 in the circumferential direction. shall have a structure that maintains airtightness. For example, as shown in FIG. 6(A), the angle .alpha. make it look like Furthermore, a sealing member may be interposed between the furnace wall elements 15. As shown in FIG.

Also, as shown in FIG. 6(B), the angle α is set to 90°, connecting members 16 are provided in gaps between the furnace wall elements 15, and the furnace wall elements 15 are connected through the connecting members 16. may be concatenated. The connecting member 16 is not limited in structure and shape as long as it can connect the furnace wall elements 15 to each other. Further, when the connecting member 16 is used, the furnace wall element 15 having the same structure can be used for the furnace segment 11 having a cross section of hexagon, octagon, decagon, or the like, simply by changing the shape of the connecting member 16. Can be configured.

Both the end plates 13 and 14 are ring-shaped, the outer shape is circular, and the inner shape is the same shape or substantially the same shape as the cross section of the space inside the furnace split 11 .

The end plate 13 has a larger diameter than the end plate 14 . The end faces of the furnace wall elements 15 are fixed to the end plates 13 and 14, respectively. The end plates 13 and 14 maintain the shape of the furnace wall 12 and serve as strength members for the furnace split body 11 . Also, the large-diameter end plate 13 functions as a rotating plate as will be described later.

Further, the end plates 13 and 14 function as connecting members when the furnace segments 11 are connected to each other, and the end plates are fixed to each other by fasteners such as bolts, so that the furnace segments 11 are integrated. be. Further, the end plate 13 functions as a rotating ring for rotatably supporting the furnace body 1, as will be described later.

Further, a partition plate element 17 is provided so as to divide the inside of the furnace split body 11 into two (up and down in the state of FIG. 3).

The partition plate element 17 will be described with reference to FIGS. 7 and 8. FIG.

The partition plate elements 17 may be provided along the diagonal lines of the even-numbered polygon, or may be provided so as to span across opposite sides of the even-numbered polygon. In this embodiment, the partition plate element 17 is provided between opposite sides.

When the furnace body 1 is configured by connecting the furnace split bodies 11, the partition plate element 17 is also connected in the same manner, and the partition plate 18 (FIGS. 9(A) and 9 (B) reference). The partition plate 18 divides the interior of the furnace body 1 into two along the axial direction, and the divided spaces form drying chambers 19,19. In the state shown in FIG. 3, the partition plate 18 divides the inside of the furnace into upper and lower halves.

The partition plate element 17 includes a flat plate 21 and a feed plate 22. The feed plates 22 are provided on the front and back sides of the flat plate 21 at a predetermined pitch in the axial direction of the furnace segment 11, respectively.

The feed plate 22 has an L-shaped cross section and is fixed to the flat plate 21 by bolting, welding, or the like. When the feed plate 22 is fixed to the flat plate 21 , the belt-like flat plate stands vertically on the flat plate 21 . The feed plate 22 may have an I-shaped cross section and be welded to the flat plate 21 . The shape and mounting method of the feed plate 22 are not limited.

The pitch between the feed plates 22 is set to be larger than the expected particle size of the object to be dried, for example, approximately twice or more. The height of the feed plate 22 is also set to be larger than the expected particle size of the object to be dried, for example, approximately twice or more.

Further, the feed plate 22 is inclined at a predetermined angle β with respect to the axis O of the furnace segment 11 . The direction of inclination of the feed plate 22 is such that when the feed plate 22 rotates integrally with the split furnace 11, the feed plate 22 moves downstream in the process in which the feed plate 22 rises from the horizontal to the vertical direction. so that it slopes down. Referring to FIG. 7, the partition plate element 17 is in a horizontal state, and the partition plate element 17 is rotated from the right side to the left side in the figure in the direction of a right screw.

The angle β is about 65° to 80°. In this embodiment, β=73°.

As described above, the furnace body 1 is constructed by connecting a plurality of furnace segments 11 having the same structure on the same axis, and the furnace body 1 is rotatably accommodated in the frame 2 there is

As shown in FIG. 2, the frame 2 includes a furnace body support frame 24 .

Horizontal beams 25 are provided at the upstream and downstream ends of the furnace support frame 24, and a pair of left and right rollers 26, 26 are rotatably mounted on each horizontal beam 25. As shown in FIG.

The roller 26 is a grooved roller, and the end plate 13 is fitted in the groove of the roller 26 so that the movement of the end plate 13 in the axial direction is restricted by the groove. The furnace body 1 is rotatably supported by the furnace body support frame 24 via the rollers 26 , and the axial direction and movement of the furnace body 1 are restricted by the rollers 26 .

A ring gear 27 (see FIG. 1) having the same or approximately the same diameter as the end plate 13 is fixed to the end plate 13 on the upstream side concentrically with the furnace body 1 . A gear 28 is provided on the furnace support frame 24 at a position facing the ring gear 27 . The gear 28 is fixed to a shaft 29 and the shaft 29 is connected to the motor 4 via a gear train 31 .

The furnace body 1 is rotated by the motor 4 via the gear train 31 , the shaft 29 and the gear 28 . The motor 4 , the gear train 31 , the gear 28 , etc. constitute a drive section for rotating the furnace body 1 .

The ring gear 27 and the gear 28 may be directly meshed with each other, or may be connected via a chain. Alternatively, the ring gear 27 and the gear 28 may be friction wheels, and the furnace body 1 may be rotated by friction drive.

The furnace body 1 is composed of a plurality of furnace segments 11, and the main components of the furnace segment 11 are a plurality of furnace wall elements 15 and one partition plate element 17, and the furnace body 1 has a simple structure. have

The operation of the rotary drying furnace will be described below.

Food waste as an object to be dried is put into the object to be dried introduction device 3 .

Based on the type and state of the food waste, the operating conditions such as the amount (volume or weight) put into the furnace body 1 per unit time, the temperature of hot air, the air volume of hot air, and the rotational speed of the furnace body 1 are controlled as described above. Set to device 8.

The controller 8 controls the temperature and flow rate of the hot air blown from the hot air generator 5 based on the set operating conditions, controls the input amount from the drying object input device 3, The rotation speed of the furnace body 1 is controlled.

The hot air from the hot air generator 5 is blown into the furnace divided into two parts by the partition plate 18, passes through the furnace, is discharged from the upstream end as exhaust gas, and passes through a duct (not shown). It reaches the exchanger 6 .

In the heat exchanger 6, heat is exchanged between the outside air sucked by the hot air generator 5 and the exhaust gas, the temperature of the outside air is raised, and the exhaust gas is cooled to a predetermined temperature and released to the atmosphere.

The food waste thrown from the drying object throwing device 3 is evenly distributed to the drying chambers 19, 19 by the rotation of the furnace body 1, especially the rotation of the partition plate 18. As shown in FIG.

In addition, since the food waste is evenly distributed among the drying chambers 19, 19, the contact area between the food waste and the hot air is increased, and the drying efficiency is improved.

Behavior of food waste in the drying chamber 19 will be described with reference to FIGS. 10 and 11. FIG.

Assuming that the furnace body 1 rotates, for example, clockwise in FIG. 10, the food waste 33 on the lower side in FIG. 10 will be described. In order to facilitate the explanation, the cross section of the furnace body is circular, and illustration of the food waste on the upper side is omitted.

When the furnace body 1 rotates clockwise by 90° from the state shown in FIG. When the partition plate 18 is vertical, food waste 33 accumulates below the drying chamber 19 (FIG. 11(B)).

Until the partition plate 18 rotates further and the partition plate 18 becomes horizontal, the state of the food waste 33 does not substantially change and remains at the left end of the partition plate 18 (FIG. 11(C)).

When the partition plate 18 is further rotated and tilted, the food waste 33 moves downward along the partition plate 18 due to gravity acting on the food waste 33 (FIG. 11(D)).

While the food waste 33 moves along the partition plate 18, the food waste 33 receives a downstream thrust from the feed plate 22 (see FIG. 7).

The downstream thrust acts on the food waste 33 until the partition 18 is over vertical, and the food waste 33 in the drying chamber 19 as a whole moves downstream.

When the partition plate 18 is vertical, the food waste 33 accumulates in the upright lower part of the drying chamber 19 (FIG. 11(E)). It separates from the plate 18 and accumulates in the lower portion of the horizontal drying chamber 19 (FIGS. 11(F) and 11(A)).

Thus, the food waste 33 present in each drying chamber 19 is moved downstream with each rotation of the furnace body 1 .

Also, the food waste 33 is stirred by the movement of the feed plate 22 and the inversion of the partition plate 18 . Further, since the partition plate 18 prevents the food waste 33 from moving along the inner wall, the food waste 33 is reliably turned upside down in the drying chamber 19 by the rotation of the furnace body 1 .

While the food waste 33 is moving in the drying chamber 19, it is stirred by the rotation of the furnace body 1, and by repeating the inversion, the food waste 33 is uniformly heated by the hot air. Therefore, the food waste 33 can be dried efficiently.

As described above, the partition plate 18 divides the interior of the furnace body 1 into the two drying chambers 19, 19 and evenly distributes the food waste thrown into the two drying chambers 19, 19, It has the function of moving food waste downward and stirring the food waste.

The dried food waste 33 is discharged out of the furnace through the discharge chute 7 .

The furnace body 1 can have a simple structure, and the food waste 33 can be dried easily. Therefore, the equipment cost of the rotary drying furnace can be kept low, the transportation cost of the food waste can be reduced, or the storage of the food waste can be facilitated.

In the above embodiment, the furnace body 1 may be supported so as to be inclined downward toward the downstream side. Further, when the temperature of the exhaust gas becomes low, the heat exchanger 6 may be omitted and the exhaust gas may be released directly from the furnace body 1 to the outside air.

Another embodiment will be described with reference to FIG. In FIG. 12, the same reference numerals are given to the same parts as those shown in FIG. 1, and the explanation thereof will be omitted.

Another embodiment shows a case in which three furnace split bodies 11 are arranged in series. The structure for rotatably supporting the furnace segment 11 and the structure for rotationally driving the furnace segment 11 are the same as those in the above-described embodiment, and are not shown.

In FIG. 12, 35 indicates an exhaust duct.

The exhaust duct 35 has an upstream end connected to the upstream end of the furnace body 1 and a downstream end connected to the heat exchanger 6 .

A joining ring 36 is provided on the surface of the exhaust duct 35 joined to the upstream end of the furnace body 1 , and the joining ring 36 is joined to the end plate 13 at the upstream end of the furnace body 1 . A sealing material is provided between the end plate 13 and the joint ring 36 to seal the space between the end plate 13 and the joint ring 36, and the end plate 13 is attached to the joint ring 36. It is rotatable.

The object-to-be-dried loading device 3 provided on the upstream side of the furnace body 1 has a hopper 37 for storing food waste and a screw conveyor 38 . The screw conveyor 38 is provided concentrically with the furnace body 1, passes through the upstream end of the exhaust duct 35, the joint ring 36, and the end plate 13, and has an open end inside the furnace body 1. . The screw conveyor 38 cuts out the food waste from the hopper 37, conveys it, and discharges the food waste into the furnace body 1 from its tip. In FIG. 12, 39 is a motor for driving the screw conveyor 38 .

The interior of the furnace body 1 and the interior of the exhaust duct 35 communicate with each other through a ring-shaped space formed around the screw conveyor 38 .

A discharge chute 7 is provided at the downstream end of the furnace body 1 , and a joining ring 41 is provided on a surface of the discharge chute 7 to be joined to the end plate 13 at the downstream end of the furnace body 1 , so that the end plate 13 and the end plate 13 are connected. A sealing material is provided between the joining ring 41 and the joint ring 41 . The end plate 13 is rotatable with respect to the joint ring 41 and is sealed between the end plate 13 and the joint ring 41 .

The interior of the furnace body 1 and the interior of the discharge chute 7 are communicated with each other through the hollow portions of the end plate 13 and the joint ring 41 .

The downstream end of the partition plate 18 protrudes to the inside of the discharge chute 7, so that the food waste sent by the partition plate 18 is surely dropped into the discharge chute 7. there is A damper 42 is provided at the discharge port 7a of the discharge chute 7, and the discharge port 7a is opened and closed by the damper 42. As shown in FIG.

The damper 42 closes the discharge port 7a when the furnace body 1 is not rotating or when the screw conveyor 38 is not driven. When the screw conveyor 38 is driven, the discharge port 7a is opened. Alternatively, the discharge port 7a may be opened when a predetermined amount of dried food waste accumulates in the discharge chute 7. FIG.

The hot air generator 5 sucks outside air into the heat exchanger 6 through an air inlet 40, and takes in the outside air whose temperature has been raised from the heat exchanger 6 through a duct 40a. The hot air generator 5 heats the outside air to a predetermined temperature and blows the hot air into the furnace body 1 through the discharge chute 7 .

The blown hot air circulates inside the furnace body 1, flows into the upstream end of the exhaust duct 35, circulates through the exhaust duct 35, passes through the heat exchanger 6, and exits the furnace from the exhaust port 35a. Ejected.

The heat exchanger 6 exchanges heat between the exhaust gas and the outside air and recovers the waste heat of the exhaust gas to improve the thermal efficiency of the rotary drying furnace. As the heat exchanger 6, the heat exchanger disclosed in Patent Document 2 can be used.

In the above embodiment, the object to be dried is described as food waste, but the object to be dried may be wood waste containing moisture.

In this embodiment, the furnace body 1 is mainly composed of furnace segments 11 having the same structure, and the furnace segments 11 can be connected to each other. The required number of furnace division bodies 11 can be constructed from the body 11 . Therefore, it is possible to easily manufacture the furnace body 1 corresponding to the required processing amount of food waste. Furthermore, by making the furnace split body 11 into a standardized unit, it is possible to manufacture in a short delivery time and to reduce the manufacturing cost.

Furthermore, the furnace wall elements 15 having the same structure constitute the furnace segment 11, and the production of the furnace wall element 11 is basically the work of connecting the furnace wall elements 15 so as to form a polygon. As a result, the fabrication of the furnace split body 11 is facilitated. Further, by using the furnace wall element 15 as a common part, the unit price of the part can be reduced and the part can be easily managed.

Furthermore, since the furnace wall element 15 and the partition plate element 17 are formed of flat surfaces, there is no machining of curved surfaces when manufacturing the furnace wall element 15 and the partition plate element 17, so that the machining is simple and the production cost is low. can be suppressed.

Further, since the furnace segment 11 is a polygon formed by connecting flat furnace wall elements 15, the cross-sectional shape of the furnace segment 11 can be arbitrarily hexagonal, octagonal, decagonal, or the like depending on the number of connections. can be selected. Furthermore, since the diameter of the furnace split body 11 is increased in accordance with the number of the furnace wall elements 15 to be connected, it is possible to manufacture furnace split bodies 11 of various sizes required by the furnace wall elements 15 of the same part. It becomes possible.

As described above, the rotary drying furnace according to the present embodiment can be manufactured with a simple structure, and a rotary drying furnace corresponding to the required throughput can be easily manufactured by using common parts and common units. can be done.

REFERENCE SIGNS LIST 1 furnace body 3 object loading device 4 motor 5 hot air generator 6 heat exchanger 7 discharge chute 8 control device 11 divided furnace body 13 end plate 15 furnace wall element 17 partition plate element 18 partition plate 19 drying chamber 21 flat plate 22 feed Plate 24 Furnace support frame 26 Roller 27 Ring gear 28 Gear 29 Shaft 33 Food waste 35 Exhaust duct 37 Hopper 38 Screw conveyor 42 Damper

Claims (3)

A furnace body having at least one furnace segment that can be connected in series, a frame that rotatably accommodates the furnace body, and a frame that is provided downstream of the furnace body and circulates hot air toward the upstream side in the furnace. an object-to-be-dried input device provided on the upstream side of the furnace body for introducing an object to be dried from the upstream end of the furnace body; and a drive unit for rotating the furnace body, The split body is constructed by connecting rectangular plate-shaped furnace wall elements in the circumferential direction so that the cross section of the furnace split body becomes an even-numbered polygon. The partition plate element has a flat plate and feed plates provided on the front and back sides of the flat plate at a predetermined pitch. A rotary drying furnace that is tilted with respect to the axis of the furnace split so as to move downstream. A heat exchanger is further provided, wherein the hot air generator heats and blows the outside air sucked through the heat exchanger, and the exhaust gas discharged from the upstream end of the furnace body is sent to the heat exchanger through an exhaust duct. 2. The rotary drying furnace according to claim 1, wherein the air is guided and discharged after exchanging heat with the outside air in the heat exchanger. The hot air generator is provided in the furnace body via a discharge chute, the discharge chute has a damper at the discharge port, and the drying object loading device includes a hopper for storing the drying object, and and a screw conveyor for cutting out the material to be dried and discharging it to the upstream end of the furnace body, wherein the damper is closed when the rotation of the furnace body is stopped or when the screw conveyor is stopped. 2. The rotary drying oven according to 1.

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