JP3418788B2 - Continuous treatment type heating furnace and carbonization method using the same - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention is suitable for carbonizing industrial wastes such as animal and plant residues such as food wastes, livestock sludges, chicken manure, sewage sludges, or industrial sludges by closed heating. The present invention relates to a heating furnace and a carbonization method using the same, and particularly to a continuous processing type heating furnace and a heating furnace for moving a raw material along a predetermined path in a closed heating space and performing heating during the movement. The carbonization method was used.

[0002]

2. Description of the Related Art Conventionally, a carbonization apparatus used for reducing, recycling, and recycling wastes generated in daily life and industrial processes has been known. Among such carbonization devices, a continuous treatment type carbonization device that continuously supplies raw materials such as waste to perform carbonization is shown in Utility Model Registration No. 3009966.

FIG. 1 shows a conventional continuous treatment type carbonization apparatus 90.
The longitudinal section of is shown. In this apparatus 90, hollow linear raw material transfer cylindrical pipes 94 are arranged in a square tube-shaped furnace body 92 in a zigzag form from top to bottom. Raw materials such as livestock sludge supplied into the pipe 94 are continuously transferred by rotating a screw conveyor 96 extending in the pipe 94. Screw conveyor 9
Reference numeral 6 denotes a central shaft rod provided with a spiral blade in a screw shape, and the raw material is transferred according to the rotation of the blade. In this way, the raw material horizontally moves in the pipe 94 and drops to the pipe in the immediately lower stage at the connecting portion provided at the end of the pipe. By repeating this operation from the upper stage to the lower stage, Move continuously.

During the transfer of the raw material, the pipe 94 is heated by the combustion gas from the combustion chamber 98, whereby the raw material moving in the pipe is dehydrated, dried and carbonized by the screw conveyor 96. The raw material carbonized in this way is discharged to the outside of the apparatus through the discharge port provided in the lowermost pipe.

[0005]

However, in the above-mentioned carbonization device 90, since the transfer pipe 94 that extends linearly in the furnace body 92 is provided in a zigzag shape, from the raw material supply port to the discharge port. It was not easy to lengthen the route. That is, in this case, it is necessary to increase the number of stages of the straight pipes 94 or increase the pipe length of each stage. In either case, the plane shape of the entire device becomes elongated and the height is increased. It may be difficult to install the device in a stable manner. Or, in order to perform stable installation, it is necessary to additionally provide a supporting member. Therefore, in practice, the overall length of the pipes arranged in a zigzag shape was designed to be relatively short.

Further, in such a pipe arrangement, there is a tendency that heat is not efficiently transferred from the heating device to the pipe. That is, the combustion gas, which is a heat transfer medium, rises vertically in the furnace body 92 while being diffused radially, so that it is evenly and efficiently distributed in the pipe linearly provided in the horizontal direction. , It was difficult for heat to be transferred.

Further, in this apparatus, since the raw material is transferred using the screw conveyor rotating in the pipe as described above, when the raw material contains a large amount of water,
If the viscosity is high, it may cause clogging and may not be properly transferred in the pipe. Further, since the raw material enters a compressed state as if the raw material was squeezed during the transfer by such a screw conveyor, it was not possible to obtain the carbide discharged from the apparatus in the form of granules or the like.

The present invention has been made in order to solve the above problems, and has a heating furnace of good heating efficiency and capable of transferring raw materials such as wastes satisfactorily, and a carbonization method using the same. The purpose is to provide.

[0009]

A continuous processing type heating furnace according to the present invention includes a furnace body having a cylindrical furnace wall and a lid portion provided at an upper end opening of the furnace wall, and a furnace body supporting the furnace body. And a plurality of hollow annular members arranged side by side at intervals along the axial direction of the furnace wall, each of a plurality of hollow annular members forming an annular shape along the inner peripheral surface of the furnace wall, A rotary member that is supported by the furnace body inside each of the plurality of hollow annular members and is rotatable along the hollow annular members, and through a slit formed in the circumferential direction of the hollow annular members. A rotating member provided with a plurality of raw material transfer vane members extending into the hollow annular member, a drive unit connected to the rotating member to drive the rotating member, and heating for heating the plurality of hollow annular members. Means, provided at the top of the furnace body, at the top A raw material supply port that communicates with the hollow annular member that is provided, and a raw material discharge port that is provided in the lower portion of the furnace body and that communicates with the hollow annular member that is located at the bottom, and that has a plurality of lined up in the axial direction Adjacent hollow annular members of the hollow annular members are communicated with each other via a communicating portion provided with an opening provided in each of the adjacent hollow annular members, and among the communicating portions of the hollow annular members arranged in the axial direction, The above-mentioned object is achieved by providing the communicating portions adjacent to each other in the axial direction at positions displaced in the circumferential direction of the hollow annular member.

The heating means may include a combustion chamber provided below the furnace body and having an opening for supplying a heating gas to a space in the furnace body in which the intermediate annular member is provided. It may be.

A plurality of annular blades extending concentrically along the inner peripheral side of the hollow annular member are provided on the hollow annular member and the rotating member respectively, and the annular blade of the hollow annular member and the annular blade of the rotating member are provided. And may be in mesh with each other so as to increase the shielding property inside and outside the hollow annular member.

Alternatively, the carbonization method of the present invention is a method of carbonizing a carbon-containing material using the heating furnace of the present invention, and a step of supplying granular carbon-containing material to the raw material supply port of the heating furnace. And inside the plurality of hollow annular members heated by the heating means, the supplied granular carbon-containing material is moved by pressing the plurality of raw material transfer vane members in the circumferential direction. The above object is achieved by including a step of heating the carbon-containing material and a step of discharging the carbonized carbon-containing material in a granular form from the raw material discharge port of the heating furnace.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION A heating furnace according to an embodiment of the present invention will be described below with reference to the drawings.

2 and 3 show the structure of the heating furnace 1 according to this embodiment. 2 and 3 show a cross section of the heating furnace 1 when viewed from directions different from each other by 90 °.

The heating furnace 1 includes a furnace body having a lid 4 and a cylindrical wall (furnace wall) 6 surrounding the heating space 2, and an annular shape supported by the inner wall of the cylindrical wall 6 in the heating space 2. Raw material transfer as a rotary member configured by a plurality of hollow transfer path members 10 formed, a blade 22 arranged so as to circulate in the transfer path member 10 and a drive shaft 26 connected to the blades 22 via spoke members 24. Device 20 and burner 32
And heating means 30 constituted by the combustion chamber 34 (FIG. 3)
With.

The furnace body (the lid 4 and the cylindrical wall 6) surrounding the heating space 2 and the inner wall of the combustion chamber 34 of the heating means 30 are
It is covered with a heat-resistant member of castable refractory material or the like having a predetermined thickness to provide fire resistance.

The transfer path members 10 are arranged in parallel along the axial direction A of the cylindrical wall 6 in a 7-step configuration.
Is supported by the support member 6a. Each transfer path member is configured to have, for example, a rectangular shape with an inner circumference of about 10 cm square and an annular shape with a diameter of about 1 m. Of these transfer path members, the uppermost (first step) transfer path member 10a has a supply pipe 12 that communicates with the transfer path member 10a and extends above the lid portion 4. The supply port 8 located at the end of the supply pipe 12 has, for example, a hopper 80 for accumulating raw materials.
It is designed so that it can be connected to the outlet of a container such as. With such a structure, the raw material can be charged into the uppermost transfer path member 10a from the outside of the apparatus. It is also possible to use various conventional supply means for supplying the raw material to the supply port 8 of the heating furnace 1.

Further, the uppermost transfer path member 10a is connected to the outer cylinder 50 extending from the upper side of the lid portion 4 to the outside of the furnace main body, so that the gas which may be generated at the time of carbonization in the heating process of the raw material is not generated. The structure is such that it passes through the outer cylinder 50 and is guided into the combustion chamber 34 by a blower 52 or the like arranged at the outer bottom of the furnace body.

In addition, in the transfer path members 10 from the second step to the sixth step, the upper transfer path member (for example, the second step) of the two transfer path members adjacent to each other in the axial direction A.
Of the lower side of the transfer path member and the upper surface of the lower transfer path member (for example, the third step) are provided so that the openings face each other, and these openings extend in a substantially vertical direction (axial direction). Connected by. As a result, the adjacent transfer path member communicates with the outside of the transfer path member while being shielded. The positions of the openings (or the communication pipes) provided on the bottom surface of each of the transfer path members are shifted in the circumferential direction by, for example, about 30 ° toward the upstream side in the transport direction described later, as the position goes down. Therefore, the openings are not located at the same position in three or more adjacent stages. Further, an opening communicating with the discharge pipe 14 extending outside the furnace body is provided on the bottom surface of the transfer path member 10b at the lowermost stage (seventh stage). It should be noted that various types of supporting members may be provided between the transfer path members at each stage, and thus each transfer path member can be appropriately supported.

FIG. 4 shows a plurality of annular hollow transfer path members 1
An example of the structure of the constituent member 100 for forming 0 is shown. The transfer path member 10 includes a lower half 102 of an upper transfer path member and an upper half half of a lower transfer path member among the adjacent transfer path members as shown in FIGS. 4A and 4B. It is formed by manufacturing a plurality of doughnut-shaped constituent members 100 that are joined to 104, stacking them, and fixing the outer peripheral sides to each other with bolts or the like. At this time, a predetermined gap is provided between the two connected component members 100 at positions on the inner peripheral side thereof. That is, a slit extending in the circumferential direction is formed on the inner peripheral side of the transfer path member formed by connecting the two constituent members 100. This is to enable the rotary vane member 28 (FIG. 6) described later to extend outside the transfer path member through this slit. Note that these members can be made of stainless steel, for example.

In this structural member 100, a communication pipe 106a for communicating the upper transfer path member and the lower transfer path member is provided with a bottom surface of the lower half 102 of the upper transfer path member and an upper half 104 of the lower transfer path member. Are connected to the opposing openings 106 provided on the upper surface of the. Further, three annular blades 109 that form two circumferential grooves 108 are provided at positions near the inner circumference of the component member 100. This is a rotary blade member 28 including a plurality of blades 22 described later.
It can be fitted with the convex wall (annular blade) 284 (FIG. 6) and is provided to shield the inside of the transfer path member from the heating space 2.

The multi-stage transfer path member 10 thus provided in an annular shape can form a relatively long transfer path (about 3 m or more) per step. According to the structure of the apparatus of the present embodiment as described above, the apparatus 1 as a whole is stably installed, and in the cylindrical heating space 2, the supply port 8 of the supply pipe 12 to the discharge port 16 of the discharge pipe 14 are provided. It is possible to obtain a relatively long path of travel.

FIG. 5 shows a cross section taken along line XX of FIG. As shown in the drawing, a rotary vane member 28 including, for example, 20 vanes 22 is installed inside the annular transfer path member 10. The rotary vane member 28 is fixed to the six spoke members 24 by bolting or the like through the circumferentially extending slits formed on the inner peripheral side of the transfer path member 10 described above. The spoke member 24 is fixed to the drive shaft 26. In this way, the rotary wing member 28 can be rotated around the axis by the axial rotation of the drive shaft 26, and the wing plate 22 arranged in the transfer path member 10 can be orbitally linked.

FIG. 6 is an enlarged view of the rotary vane member 28 shown in FIG. As shown in FIG. 6A, the rotary vane member 28
Has a doughnut-shaped base portion 282 made of stainless steel having a thickness of, for example, about 9 mm, and 20 stainless steel blades 22 radially arranged and fixed at a predetermined interval along the outer periphery of the base portion 282. There is. It should be noted that the number of blades can be appropriately selected as desired. In addition, two annular convex walls (annular blades) 284 extending in the circumferential direction are provided on the front and back surfaces of the donut-shaped base portion 282. These convex walls slidably fit with the concave grooves 108 (FIG. 4) formed on the inner surface of the transfer path member 10 as described above (that is, concentric along the inner peripheral side of the transfer path member 10). The annular blade 109 provided in a circular shape and the annular blade 284 provided concentrically with the rotary vane member 28 mesh with each other to form the labyrinth structure 18 as shown in FIGS. 2 and 3. With such a structure, the airtightness inside the transfer path member 10 can be enhanced, and the blades 22 arranged inside the transfer path member 10 can be rotated by the axial rotation of the drive shaft 26 located outside thereof. .

The operation of the heating furnace 1 configured as described above will be described below with reference to FIGS. 2 and 3.

First, the movement path of the raw material in the heating furnace 1 will be described. Raw materials such as organic sludge and animal and plant sludge to be heated are put into the raw material supply port 8 of the heating furnace 1 by using, for example, a feeding hopper and passed through the supply pipe 12 into the uppermost transfer path member 10a. Supplied.

On the other hand, the drive shaft 26 is axially rotated about the central axis A, whereby the plurality of blades 22 arranged in the transfer path member 10 interlock with each other and move in translation along the circumferential direction. The rotation of the drive shaft 26 can be performed by transmitting the rotation of the drive motor 29 provided in parallel to the engagement portion of the drive shaft 26 extending beyond the lid portion 4 by the chain 29a. The rotation speed of the drive shaft 26 is
For example, it is set to 1/2 round per minute. In addition, the direction of rotation is such that a communication pipe that connects the transfer path members (FIG. 4).
Depending on the arrangement, the direction in which the material can circulate in each of the transfer path members for almost one round is appropriately selected.

In this way, the raw material circulates inside the transfer path member 10a while being pushed by the blades 22. The heating furnace 1 of the present embodiment is preferably the upper end portion 22 of the blade 22.
A predetermined gap is provided between a and the upper surface of the transfer path member 10, so that an escape path for the raw material is ensured and a flow path for gas generated from the raw material is also secured. The raw material transferred in this way is moved by being pressed by the translational movement of the blades, so that it is not compressed and solidified so as to be squeezed during the movement unlike the case of using a screw conveyor.

When the inside of the transfer path member 10a of the first stage has been circulated almost once, the raw material passes through the opening provided in the bottom surface of the transfer path member 10a and drops in the communicating pipe, and the transfer path member of the second step is formed. Sent to. Similarly, the raw material sent to the second-stage transfer path member is sent to the third-step transfer path member after passing through the opening, passing through the opening, and dropping in the communication pipe. After that, the same operation is repeated until the 7th step, which is the lowest step, and each step is transferred. The raw material reaching the lowermost transfer path member 10b is transferred to the transfer path member 1
It is sent to the discharge pipe 14 extending to the outside of the furnace main body through the opening provided on the bottom surface of 0b. A transfer means such as a screw conveyor is provided in the discharge pipe 14, and the raw material can be sent to the discharge port 16 of the discharge pipe 14 by driving the transfer means. In addition, since the raw material is in a state of not containing much water after heating (for example, carbide) at the time of being transferred to the discharge pipe 14, the screw conveyor can be used as described above. After that, the raw material is taken out of the heating furnace 1 by opening a valve attached to the discharge port 16.

In this process, as described above, the positions of the bottom opening provided in each transfer path member 10 and the position of the supply port 8 in the circumferential direction are shifted by a predetermined distance for each step. The raw material input from the
It is not sent to the transfer path member of the stage. The raw material is continuously moved from the supply port 8 to the discharge port 16 in a hermetically sealed state while circulating in the transfer path member of each stage.

Next, heating of the raw material moved as described above will be described. As shown in FIG. 3, the burner 32 of the heating means 30 provided below the furnace body is
Fire a flame within 4. Here, the temperature in the combustion chamber 34 is, for example, about 800 ° C to about 900 ° C. As a result, the combustion gas generated in the combustion chamber 34 is heated in the partition wall 36 that separates the combustion chamber 34 and the heating space 2 from the upper surface inside the transfer path member 10 and at a position near the drive shaft 26. It flows into the heating space 2 through the supply hole 38. A plurality of the gas supply holes 38 are preferably arranged symmetrically on the partition wall 36.

The combustion gas flowing from the gas supply hole 38 into the heating space 2 heats the inner peripheral side of the transfer path member 10 at each stage, and the vicinity of the lid 4 of the heating furnace (the maximum temperature of the heating space 2). Up). After that, the combustion gas reaching the vicinity of the lid portion 4 moves toward the cylindrical wall 6, descends while heating the outer peripheral side of the transfer path member 10, and is provided on the cylindrical wall 6 at the lowermost part of the heating space 2. Chimney 4 through the exhaust port 40
It passes through 2 and is discharged to the outside as combustion exhaust gas.

As described above, according to the heating furnace 1 of the present embodiment, the inner peripheral surface side of the transfer path member 10 is heated in the ascending process of the combustion gas for heating, and the outer peripheral surface of the transfer path member 10 is in the descending process. Since the transfer path member 10 can be heated by the two paths of heating the side, the heat transfer efficiency is improved. Further, since the transfer path member 10 is indirectly heated by the gas conduction or the radiant heat without being directly heated by the flame by causing the combustion gas to flow in through the gas supply hole 38, the transfer path member 10 may be damaged. Will be reduced. In the heating furnace 1 of the present embodiment that performs such indirect heating, the temperature in the heating space 2 is, for example, about 5
The temperature is set to 00 ° C to about 600 ° C.

Further, the temperature of the high temperature combustion gas flowing in from the gas supply hole 38 decreases as it rises in the heating space 2, and then further decreases as it falls. Therefore, the heat applied to the transfer path member 10 at each stage is the total height of the heat from the inner peripheral side and the heat from the outer peripheral side, that is, the height at which the transfer path member 10 is provided (that is, the combustion chamber). It becomes uniform regardless of the distance from 34). By uniformizing the heat given to the transfer path members of each stage in this way, the temperature of the raw material passing through the inside can be kept relatively constant. In this way, the raw material that moves from the supply port to the discharge port can be heated at a constant temperature, so that an action such as carbonization due to heating can be appropriately obtained.

As described above, also in the heating furnace of this embodiment, the raw material in the transfer path member is heated in a sealed state as in the case of the conventional carbonization device and the like, so that explosion or gas leakage occurs. It does not happen. Further, as shown in FIGS. 2 and 3, the heating furnace 1 includes an outer cylinder 50 that communicates with the transfer path member 10 to form a gas flow path, and a gas that may be generated during carbonization during the heating process of the raw material. Blower 5
Since it is guided to the inside of the combustion chamber 34 by 2 or the like and burned, it is prevented from being directly discharged to the outside world, and the generation of foul odors and smoke can be suppressed.

As described above, according to the heating furnace of this embodiment, since the heating is performed while the material is transferred by the translational motion of the blades in the annular transfer path member, the moisture content is high. Even if it is a raw material, it is not clogged and can be efficiently heated. Further, for example, when the heating furnace of the present embodiment is used to adjust the water content of the raw material, the control of the heating time of the raw material can be easily achieved by controlling the rotation speed of the blades, that is, the rotation speed of the drive shaft. It is more accurate than controlling the burner's heating power to do this and allows proper moisture control.

Further, for example, when a granular (granular) raw material having a diameter of about 5 to about 10 mm is introduced from the raw material supply port,
It is possible to carbonize while maintaining the granular state, because the pressure is not excessively increased during the transfer as in the case of the screw conveyor. For example, a carbide obtained in a granular state with a diameter of about 5 mm is unlikely to flow out due to rain unlike a powder, and thus is advantageously used in various applications. The carbide thus obtained is suitable for use as a fertilizer, for example.

The present invention has been described above based on the embodiment. For example, the number of stages of the hollow annular transfer path member 10,
The connection form between the drive shaft and the blades may be changed as appropriate, and various forms are possible. Further, the transfer path member 10 and the rotary vane member 28 may be formed of various metals having good heat resistance and corrosion resistance, ceramics, or the like, other than stainless steel.

Further, the heating furnace of the present invention can be used for carbonizing various materials and adjusting water content. For example, it can be used for carbonization of various agricultural and marine wastes such as food waste such as coffee husks, sewer dewatering sludge, human waste, livestock sludge, and livestock waste. It can also be used for carbonizing biodegradable plastic (non-petroleum plastic) products such as caprolactone containers by adjusting the heating temperature and time.

[0040]

According to the heating furnace of the present invention, since the raw material is transferred while being hermetically heated by the pressing of the blades circulating in the annular hollow member, the raw material can be efficiently heated. Further, the raw material after heating can be obtained in a shape substantially similar to the shape when the raw material is supplied to the heating furnace without being compressed so as to squeeze the raw material during transfer. Further, if heating gas is supplied from the combustion chamber to heat the hollow annular member,
Since the hollow annular member is indirectly heated, the damage that can be received is smaller than in the case of direct heating by a flame. With such a configuration, the heating furnace can be downsized and the cost can be reduced.

Alternatively, according to the carbonization method using the heating furnace of the present invention, it is possible to obtain a granular carbide by heating the carbon-containing material supplied in the granular form. Such carbides are
It is less likely to flow out due to rain compared to powder and is suitable for use in various applications.

[Brief description of drawings]

FIG. 1 is a front view showing a conventional carbonization device.

FIG. 2 is a vertical cross-sectional front view of the heating furnace according to the embodiment of the present invention viewed from a predetermined direction.

FIG. 3 is a vertical sectional side view of the heating furnace shown in FIG.

4A and 4B are views showing constituent members for forming an annular transfer path member of the heating furnace shown in FIG. 2, FIG. 4A being a plan view, and FIG. 4B being a view showing FIG. 4A. It is sectional drawing which followed the YY line.

5 is a sectional view taken along line XX of the heating furnace shown in FIG.

6A and 6B are views showing a rotary vane member of the heating furnace shown in FIG. 2, FIG. 6A being a plan view and FIG. 6B being a cross section taken along line ZZ of FIG. 6A. It is a figure.

[Explanation of symbols]

1 heating furnace 2 heating space 4 Lid 6 Cylindrical wall (furnace wall) 8 supply ports 12 Supply pipe 10 Movement path member 14 Discharge pipe 16 outlet 18 Labyrinth structure 20 Transfer device (rotating member) 22 feather board 24 spoke members 26 Drive shaft 29 Drive motor 30 heating means 32 burners 34 Combustion chamber 36 bulkheads 38 Gas supply hole 40 exhaust port 42 chimney

Continuation of front page (56) Reference JP-A-11-60225 (JP, A) JP-A-50-47472 (JP, A) JP-A-10-8063 (JP, A) JP-A-57-96084 (JP , A) JP 54-58972 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) F23G 7/00 C10B 53/00 B09B 1/00-5/00

Claims (4)

(57) [Claims] 1. A continuous processing type heating furnace for continuously performing heat processing while moving a raw material along a moving path, wherein a cylindrical furnace wall and a lid portion provided at an upper end opening of the furnace wall. And a plurality of hollow annular members supported by the furnace body and arranged in parallel along the axial direction of the furnace wall at intervals, each on the inner peripheral surface of the furnace wall. A plurality of hollow annular members that are annular along the hollow annular members, and a rotating member that is supported by the furnace body inside each of the plurality of hollow annular members and is rotatable along the hollow annular members, A rotary member provided with a plurality of raw material transfer vane members extending into the hollow annular member through slits formed in the circumferential direction of the member; and a drive unit connected to the rotary member to drive the rotary member, Heating means for heating the plurality of hollow annular members A raw material supply port provided at the upper part of the furnace body and communicating with the hollow annular member located at the uppermost part, and a raw material discharge port provided at the lower part of the furnace body and communicating with the hollow annular member located at the lowermost part An outlet and an adjacent hollow annular member of the plurality of hollow annular members arranged in the axial direction are communicated with each other through a communication portion having an opening provided in each of the adjacent hollow annular members, and the axial line Among the communication parts of the hollow annular members arranged in the direction, the communication parts adjacent to each other in the axial direction are provided at positions displaced in the circumferential direction of the hollow annular member. 2. The heating means includes a combustion chamber provided below the furnace body, the combustion chamber having an opening for supplying a heating gas to a space in the furnace body in which the intermediate annular member is provided. The heating furnace according to claim 1, wherein: 3. A plurality of annular blades concentrically extending along the inner peripheral side of the hollow annular member are provided in the hollow annular member and the rotating member, respectively, and the annular blade of the hollow annular member and the rotating member are provided. The heating furnace according to claim 1 or 2, wherein the annular blade is meshed with the hollow annular member so as to increase shielding properties inside and outside the hollow annular member. 4. A method of carbonizing a carbon-containing material by using the heating furnace according to claim 1, comprising supplying a granular carbon-containing material to the raw material supply port of the heating furnace, Inside the plurality of hollow annular members heated by the means, the supplied granular carbon-containing material is moved by pressing by the circumferential movement of the plurality of raw material transfer vane members, and the carbon-containing A carbonization method comprising: a step of heating a material; and a step of discharging a carbonized carbon-containing material in a granular form from a raw material discharge port of the heating furnace.