JP2014006038A - Indirect heating type dryer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an indirect heating type dryer which has a simple structure and enables easy inclination angle adjustment.SOLUTION: An indirect heating type dryer 1 heats and dries a processed object while transferring the processed object in a predetermined transfer direction T. The indirect heating type dryer 1 includes: a body part 8 to which the processed object is supplied and which performs dry treatment; and support mechanisms 6 provided at both sides of the body part in the transfer direction. Each support mechanism includes: a support part 17 which supports the body part at its upper part so that the body part can be rotated around a shaft 21 along a direction perpendicular to the transfer direction; and height adjustment means 18 which is provided between the support part 17 and a base surface 14 and adjusts a height of the support part.

Description

  The present invention relates to an indirect heating type drying apparatus that heats and drys an object to be treated such as waste in a predetermined conveying direction.

  Since various materials such as various biomass and waste (sludge) contain a large amount of moisture, drying treatment by heating may be performed using a drying device. As a conventional drying apparatus, for example, a casing having a U-shaped cross section, two hollow shafts rotating in opposite directions inside the casing, and hollow stirring blades arranged on the outer periphery of the hollow shaft are provided. Indirect heating type drying apparatuses are known.

  In this indirect heating type drying apparatus, the sludge is supplied to the object storage space provided between the casing and the hollow shaft from the sludge supply port provided at the upstream end in the conveying direction of the casing, and then rotated and stirred. While being stirred by the wing (disk), it is dried while being gradually conveyed to the downstream side by the gravity action by the inclination of the casing and the stirring by the rotation of the stirring wing.

  Meanwhile, the object to be treated is heated and dried by the heat exchange medium such as steam, heat transfer oil, hot water, etc., introduced into the hollow shaft, hollow stirring blade, and casing, and the sludge discharge port at the rear end of the casing More discharged outside the machine.

  By the way, in the conventional indirect heating type drying apparatus, the inclination angle of the casing is constant (fixed), and depending on the properties (type, moisture content, viscosity, adhesion, etc.) of the object to be treated, the sludge drying treatment is appropriate. There was a problem of disappearing. For example, when the sludge fluidity is high and the sludge filling rate in the indirect heating dryer is low, the emptying disc (heat transfer area of the disc exposed without contact with the sludge) and the empty casing in the drying device (The heat transfer area of the casing exposed without contact with the sludge) is large, waste space in the casing, heat transfer of the heat transfer surface (air burning) occurs, the heat loss is large, and the drying efficiency is reduced. Become.

  On the other hand, when the fluidity of the sludge is low, the sludge is excessively heated, the treatment time is lowered due to a long residence time, or the sludge is blocked in the machine. That is, the sludge has various properties, and the conveyance speed (retention time) varies depending on these, but the height of the support base or foundation is fixed. It became constant, and it was not possible to adjust the appropriate mud feed rate (residence time) according to the properties of the substance to be dried.

With respect to this problem, Patent Document 1 describes a structure that can arbitrarily adjust the inclination angle of the drying apparatus main body. This structure includes a screw hole provided in a support base that supports the drying apparatus main body, and a screw that is screwed into the screw hole and abuts on a base surface on which the support base is installed.
Patent Document 2 describes a structure in which the inclination angle of the drying apparatus main body is adjusted by a plurality of plates.

Japanese Patent Laid-Open No. 62-019326 Japanese Patent No. 4322896

However, although the drying apparatus described in Patent Document 1 can arbitrarily adjust the inclination angle of the drying apparatus body, since the inclination angle adjuster is perpendicular to the installation surface (horizontal plane), there is a limit to the adjustment of the inclination angle. There was a problem that there was.
Moreover, since the drying apparatus described in Patent Document 2 has a configuration in which a plate is inserted into a wedge-shaped gap, there is a problem that the shape of the plate is special and angle adjustment is not easy.

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide an indirect heating-type drying apparatus having a simple structure and capable of easily adjusting an inclination angle.

In order to achieve the above object, the present invention employs the following means.
That is, the indirect heating type drying apparatus according to the present invention is an indirect heating type drying apparatus that heats and dries the object to be processed in a predetermined conveying direction, and is supplied with the object to be dried. And a support mechanism provided on both sides of the main body in the transport direction, and the support mechanism supports the main body so as to be rotatable about an axis along a direction perpendicular to the transport direction at the top. And a height adjusting means provided between the support portion and the base surface for adjusting the height of the support portion.

According to the said structure, the conveyance speed in the main-body part of a to-be-processed object can be controlled by adjusting the height adjustment means and changing the inclination-angle of a main-body part. That is, the residence time of the object to be processed in the main body can be controlled.
In addition, since the support portion of the support mechanism is rotatable about the axis along the direction orthogonal to the transport direction, height adjustment using the height adjusting means, that is, adjustment of the inclination angle becomes easy. Moreover, the structure of the height adjusting means can be simplified.

Moreover, the indirect heating type drying apparatus which concerns on this invention WHEREIN: It is preferable that the said height adjustment means has an air spring.
According to the said structure, adjustment of the inclination-angle of a main-body part by a height adjustment means can be implemented more easily.

Moreover, the indirect heating type drying apparatus which concerns on this invention WHEREIN: The said height adjustment means is good also as a structure which has the laminated | stacked space | interval holding piece which can be removed.
According to the said structure, the structure of a height adjustment means can be simplified more.

Further, in the indirect heating type drying apparatus according to the present invention, detection means for detecting at least one of the amount of the object to be processed in the main body and the flow state of the object to be processed, and detected by the detection means It is preferable to have control means for controlling the height adjusting means based on the result.
According to the said structure, the inclination-angle of a main-body part can be adjusted automatically according to the property of a to-be-processed object.

According to the present invention, the conveyance speed in the main body of the object to be processed can be controlled by adjusting the height adjusting means to change the inclination angle of the main body. That is, the residence time of the object to be processed in the main body can be controlled.
In addition, since the support portion of the support mechanism is rotatable about the axis along the direction orthogonal to the transport direction, height adjustment using the height adjusting means, that is, adjustment of the inclination angle becomes easy. Moreover, the structure of the height adjusting means can be simplified.

1 is a schematic configuration diagram of a drying system according to a first embodiment of the present invention. It is AA sectional drawing of FIG. It is a schematic block diagram of the support mechanism of the indirect heating type drying apparatus which concerns on 1st embodiment of this invention. It is the schematic explaining the effect | action of 1st embodiment of this invention. It is the schematic explaining the effect | action of 1st embodiment of this invention. It is the schematic explaining the effect | action of 1st embodiment of this invention. It is a schematic block diagram of the indirect heating type drying apparatus which concerns on 2nd embodiment of this invention.

(First embodiment)
Hereinafter, a first embodiment of the present invention will be described in detail with reference to the drawings.
As shown in FIGS. 1 and 2, the drying system 2 of the present embodiment includes a feeder 4 having a hopper 3 in which the workpiece S is accommodated, and an indirect heating type for heating and drying the workpiece S. A drying device 1 (hereinafter, also simply referred to as a drying device), a boiler 5 for supplying steam to the drying device 1, support mechanisms 6 provided on both sides in the conveying direction along the longitudinal direction of the drying device 1, and a support And a control device 7 (control means) for controlling the height of the mechanism 6 as main components.

The indirect heating type drying apparatus 1 is supported by a support base 14 corresponding to a base surface via a support mechanism 6.
The drying system 2 of the present embodiment is a system that can change the inclination of the indirect heating type drying apparatus 1 by adjusting the height of the support mechanism 6.

  The drying device 1 is provided so as to cover the casing 8 (main body portion) and the outer surface on the bottom side of the casing 8, and distributes a heating medium such as steam, heat transfer oil, hot water, etc., and the casing 8 (and eventually the object to be dried). A jacket 16 (see FIG. 2) for heating the container, a conveying means 9 accommodated inside the casing 8, a supply port 10 to which the supply device 4 is connected, and a recovery device (not shown) for recovering the workpiece S. ) And a discharge port 11 connected thereto. That is, the workpiece S is input from the supply port 10 and discharged from the discharge port 11.

  The supply port 10 is provided on the upper surface of the casing 8 and at the end on the upstream side in the conveyance direction, and communicates with the inside of the casing 8. Further, the discharge port 11 is provided on the lower surface of the casing 8 at the downstream end, and communicates with the inside of the casing 8.

  Hereinafter, a direction in which the workpiece S is directed from the supply port 10 toward the discharge port 11 is referred to as a conveyance direction T. The casing 8 has a cylindrical portion 8a extending along the transport direction T, and flange portions 8b provided at both ends of the cylindrical portion 8a in the transport direction T.

  Further, the steam supplied from the boiler 5 is configured to be circulated to the boiler 5 again after being introduced into the pair of hollow rotary shafts 12 and the hollow casing 8 constituting the conveying means 9. . Furthermore, the rotating shaft 12 is provided with a plurality of stirring blades 13 (stirring plates).

Moreover, although not shown in figure, the gas discharge port which discharges | emits the dry waste gas generated by drying of the to-be-processed object S is provided in the upper part of the casing 8. FIG.
In the present invention, the “processed object S” refers to various biomass and waste containing a predetermined amount of water, and the waste includes sewage sludge, factory wastewater sludge, food waste, garbage, human waste. Examples include sludge, livestock manure, and plant juice.

  As shown in FIG. 2, the conveying means 9 of the drying apparatus 1 has two rotating shafts 12a and 12b. The rotary shafts 12a and 12b are configured to rotate in directions opposite to each other by a rotary drive device 27 (see FIG. 1) such as a motor. The rotary shafts 12a and 12b are arranged adjacent to each other in parallel with each other in the transverse direction at an interval inside the casing 8 having a U-shaped cross-sectional shape along the rotary shaft 12 at the lower part.

The stirring blade 13 has an inner peripheral end connected to the rotating shaft 12, projects in the radial direction about the axis O of the rotating shaft 12, and extends in the circumferential direction so that the central angle θ1 is about 100 to 140 °, and is substantially fan-shaped. (Half-moon shape).
A space between the rotary shafts 12a and 12b and the casing 8 serves as a workpiece storage space 15 into which the workpiece S is introduced.

  As shown in FIG. 1, the support mechanism 6 is provided at the upstream end of the casing 8 in the transport direction T and the downstream end of the transport direction T so as to support the casing 8 from below. As shown in FIG. 3, the support mechanism 6 is provided between the support portion 17 attached to the flange portion 8 b of the casing 8, and the support portion 17 and the support base 14, and adjusts the height of the support portion 17. And height adjusting means 18.

The height adjusting means 18 can change the distance between the upper surface 18a and the lower surface 18b. The height adjusting means 18 is constituted by, for example, a bellows type air spring 19, and the height can be adjusted by an automatic height control valve (not shown).
The height adjusting means 18 is not limited to a bellows type air spring, and for example, a diaphragm type air spring, an electric jack, a hydraulic jack, an electric cylinder, a hydraulic cylinder and the like can be adopted.

The support portion 17 includes a bracket 20 disposed on the upper surface 18a of the height adjusting means 18, a pin 21 extending in a direction perpendicular to the conveying direction T (longitudinal direction of the casing 8) on the upper portion of the bracket 20, and the pin 21 The rotating member 22 is attached to both ends, and the attaching member 23 connects the rotating member 22 and the flange portion 8b of the casing 8.
That is, the support portion 17 supports the casing 8 at an upper portion thereof so as to be rotatable around an axis along a direction orthogonal to the transport direction T.

The bracket 20 is placed on the height adjusting means 18 so that the side view has a substantially triangular shape and the bottom surface coincides with the upper surface 18a of the height adjusting means 18.
The pin 21 is rotatably attached to the upper part of the bracket 20.
The attachment member 23 is a plate-like member extending in the horizontal direction from the lower portion of the flange portion 8 b of the casing 8, and the rotation member 22 is provided on the lower surface of the attachment member 23.

  In the initial state, the support mechanism 6 has a predetermined inclination angle such that the height thereof decreases as the casing 8 moves in the transport direction T. The inclination angle of the casing 8 is controlled by the control device 7 according to the properties of the workpiece S and the like.

Level gauges 24 (detecting means) for measuring the amount of the object to be processed S in the casing 8 are provided inside the casing 8 and at both ends in the longitudinal direction of the casing 8. Specifically, the level meter 24 is a contact-type sensor that extends downward from above the inner peripheral surface of the casing 8, and can measure the height of the workpiece S at both ends of the casing 8. Yes.
As shown in FIG. 1, the level meter 24 is connected to the control device 7, and the control device 7 determines the object to be processed based on the heights at both ends of the casing 8 of the object S measured by the level meter 24. Estimate the amount of S.

The level meters 24 do not need to be provided at both ends of the casing 8 and may be configured to estimate the amount of the object to be processed S based on the inclination angle of the casing 8 and the height of the object S at one end of the casing 8. . Further, as the level meter 24, not only a contact type sensor but also a non-contact type sensor using infrared rays or ultrasonic waves may be used.
The means for measuring the amount of the object to be processed S is not limited to the level meter 24 described above, and may be measured by incorporating a weight meter in the height adjusting means 18 and estimating the weight of the object to be processed S. Good.

  The rotating shaft 12 is provided with a torque detector 26 so that the torque applied to the rotating shaft 12 can be measured. The torque detector 26 is connected to the control device 7 so that the load applied to the rotating shaft 12, that is, the flow state of the workpiece S can be measured.

Next, operation | movement of the drying process of the to-be-processed object S using the drying system 2 which concerns on this embodiment, and its effect are demonstrated.
First, the conveying means 9 and the casing 8 are heated. Specifically, steam (heat medium oil, hot water, etc.) generated from the boiler 5 is sent into the conveying means 9 and the casing 8, and this steam circulates through the rotary shaft 12 and the internal cavity of the casing 8. Heating is performed. And if the conveyance means 9 and the casing 8 are fully heated, the to-be-processed object S will be supplied into the inside of the drying apparatus 1 next. Specifically, the supply device 4 is operated, and the object to be processed S having a moisture content of about 60 to 100% by mass sent from the supply device 4 is sent into the drying apparatus 1 through the supply port 10.

  Further, along with the start of supply of the workpiece S, the conveyance of the workpiece S by the conveying means 9 is started. Specifically, the rotary shaft 12 is rotationally driven by the rotary drive device 27, and the stirring blade 13 transports the workpiece S along the transport direction T from the upstream side to the downstream side. Further, the object to be processed S is transported in the transport direction T by gravity due to the inclination of the casing 8.

  When the conveyance of the workpiece S by the conveying means 9 is started, the workpiece S comes into contact with the conveying means 9 and the casing 8 heated as described above, so that the workpiece S is heated. Is done. As a result, moisture contained in the workpiece S evaporates, and the moisture content of the workpiece S decreases as it is transported downstream along the transport direction T. And when the to-be-processed object S reaches | attains the most downstream end of the drying apparatus 1, according to the calorie | heat amount per time given by the boiler 5, or the conveyance time in the drying apparatus 1 by the conveyance means 9, etc. The rate changes to about 0 to 60% by mass.

  The control device 7 controls the height adjusting means 18 based on the amount of the workpiece S measured by the level meter 24 and the torque of the rotary shaft 12 detected by the torque detector 26, thereby Adjust the tilt angle automatically.

Specifically, the inclination angle of the casing 8 is adjusted so that the amount of the processing object S accommodated in the processing object accommodation space in the casing 8 becomes a predetermined amount. The inclination angle of the casing 8 can be controlled by adjusting the heights of the two height adjusting means 18.
For example, when the amount of the object to be processed S is larger than a predetermined amount determined by the specifications of the indirect heating type drying apparatus 1, the inclination angle of the casing 8 is increased as shown in FIG. By increasing the moving speed of the object S, the amount of the object to be processed S is controlled to approach a predetermined amount. That is, the inclination angle is increased so as to shorten the residence time of the workpiece S in the casing 8.

  On the other hand, when the amount of the object to be processed S is smaller than the predetermined amount, as shown in FIG. 5, the inclination angle of the casing 8 is made small (close to the horizontal), and the moving speed of the object to be processed S is made slow. Thus, control is performed to bring the amount of the processing object S close to a predetermined amount.

  In addition, the control device 7 automatically adjusts the inclination angle of the casing 8 based on the torque of the rotating shaft 12 detected by the torque detector 26. The torque of the rotating shaft 12 varies depending on the type of the workpiece S, the moisture content, the viscosity, the adhesion, and the like.

For example, when the fluidity of the workpiece S is low, the torque is larger than a predetermined torque. Therefore, as shown in FIG. 4, the inclination angle of the casing 8 is increased to increase the fluidity of the workpiece S. . That is, control is performed so as to advance the processing object S.
On the other hand, when the object to be processed S is liquid and has high fluidity, the torque becomes small. Therefore, as shown in FIG. The processing object S is retained by delaying.

Thereafter, the dried processing object S is sequentially discharged from the discharge port 11 on the downstream side of the drying apparatus 1.
As described above, according to the drying system 2 of the present embodiment, the processing object S is continuously supplied to the drying device 1 and the processing object S dried from the drying device 1 is continuously discharged. The to-be-processed object S can be dried until a moisture content becomes low enough.

  Further, when the object to be processed S is a liquid (for example, waste oil, waste liquid, etc.), the control device 7 can control the inclination angle such that the downstream side of the casing 8 has a reverse inclination angle that becomes higher. . That is, when drying the workpiece S that requires a long residence time, the height adjusting means 18 is adjusted so that the height of the casing 8 increases in the transport direction T as shown in FIG. To do.

  According to the above embodiment, the height adjustment means 18 is adjusted to change the inclination angle of the casing 8 in which the workpiece accommodation space 15 is formed, thereby conveying the workpiece S in the casing 8. The speed can be controlled. That is, the residence time of the workpiece S in the casing 8 can be controlled, and the moisture content of the workpiece S at the outlet can be adjusted.

Further, since the support portion 17 of the support mechanism 6 can rotate the casing 8 around an axis along a direction orthogonal to the transport direction T, height adjustment, that is, inclination angle adjustment is facilitated.
In addition, by adopting the air spring 19 as the height adjusting means 18, the inclination angle of the casing 8 can be adjusted more easily by the height adjusting means 18.

  In addition, the control device 7 adjusts the inclination angle of the casing 8 based on at least one of the amount of the object to be processed S and the torque of the rotating shaft 12, so that the inclination angle corresponding to the property of the object to be processed is adjusted. Automatic adjustment is possible. That is, the amount of the workpiece S and the torque of the rotating shaft 12 can be kept constant.

  Further, if the fluidity of the object to be processed S can be maintained by adjusting the inclination angle of the casing 8 and the filling rate in the drying apparatus 1 can be kept high, the heat transfer of the aired disk (the heat transfer of the disk exposed without contact with sludge) Area) and empty casing (heat transfer area of the casing exposed without contact with sludge) is reduced, so that waste space in the casing 8 and heat dissipation (air burning) of the heat transfer surface are reduced, and heat loss is reduced. Small (improvement of thermal efficiency) can improve drying efficiency.

  Further, the drying efficiency and thermal efficiency are improved by improving the sludge filling rate, and a useless heat transfer area is not required, and thus the apparatus can be miniaturized. That is, the effective heat transfer area per unit volume in the casing 8 can be increased, and the sludge contact efficiency per effective heat transfer area can be improved. In addition, by reducing the size of the apparatus, it is possible to reduce material costs and equipment costs (initial costs). In addition, the heat dissipation area is reduced by downsizing the device, so heat loss is reduced, heat efficiency is improved, and energy consumption (running cost) and maintenance cost can be reduced, reducing the life cycle cost. Reduction is possible.

  Further, when the processing object S is a liquid or the like and requires a longer drying time, it is possible to cope with a longer drying time by setting the casing 8 to an inclined angle with a reverse gradient. That is, it is possible to prevent the object to be processed S from being short-passed (discharged in an undried state) and to efficiently dry the object to be processed S.

Even if the height of the support 14 or the foundation on which the support 14 is placed is uneven, the unevenness can be absorbed by adjusting the height of the support 17.
The inclination angle of the casing 8 is also adjusted when the amount of the workpiece S in the workpiece storage space 15 varies due to the amount of the workpiece S supplied from the supply device 4 varying with time. By doing so, it is possible to cope.

  Further, since the support mechanism 6 has the attachment member 23 and the attachment member 23 is attached to the flange portion 8 b of the casing 8, the heat of the casing 8 becomes difficult to be transmitted to the air spring 19. Reliability can be improved.

  In the above embodiment, the inclination angle of the casing 8 is adjusted based on the amount of the workpiece S and the torque of the rotating shaft 12, that is, the result detected by the detection means. It is good also as a structure adjusted based on either one of the quantity of S, or the torque of the rotating shaft 12. FIG.

Further, although the height of the height adjusting means 18, that is, the inclination angle of the casing 8 is automatically adjusted by the control device 7, automatic control by the control device 7 is not essential. For example, it is good also as a structure which adjusts the inclination angle of the casing 8 manually beforehand according to the property of the to-be-processed object S, or adjusts an inclination angle manually during a driving | operation.
Moreover, it is good also as a structure which adjusts not only the inclination | tilt angle of the casing 8 but the supply amount of the to-be-processed object S supplied by the supply device 4 simultaneously.

(Second embodiment)
Hereinafter, a second embodiment of the present invention will be described in detail with reference to the drawings. In the present embodiment, differences from the first embodiment described above will be mainly described, and description of similar parts will be omitted.

  As shown in FIG. 7, the height adjusting means 18 </ b> B of the present embodiment is configured by a plate 25 that is a plurality of stacked spacing pieces instead of the air spring 19 of the first embodiment. Further, the drying system 2B of the present embodiment is not provided with the control device 7, the level meter 24, and the torque detector 26 that the drying system 2 according to the first embodiment has.

The plate 25 is a square plate-like member having a predetermined thickness, for example, and is a member for maintaining a vertical interval. The plurality of plates 25 can be removed by lifting the bracket 20 of the support portion 17 using, for example, a hydraulic jack. In other words, the height of the support portion 17 can be adjusted by adjusting the number of the plates 25.
Further, the height may be adjusted by a rectangular parallelepiped block instead of the plate-like plate 25.

According to the present embodiment, since the height adjusting means 18B is constituted by the plurality of plates 25, the height adjusting means is compared with the first embodiment in which the height adjusting means 18 is constituted by the air spring 19. The configuration of 18B can be further simplified.
Further, since the support portion 17 rotatably supports the casing 8 around the pin 21, the bottom surface of the bracket 20 can always be horizontal, so that the plate 25 can be formed by a simple flat plate. .

The present invention is not limited to the embodiment described above.
For example, in the above-described embodiment, the two rotation shafts 12 are combined. However, the present invention is not limited to this, and a combination of three or more rotation shafts may be arranged in the casing 8.

DESCRIPTION OF SYMBOLS 1 Indirect heating type drying apparatus 6 Support mechanism 7 Control apparatus (control means)
8 Casing (main body)
13 Stirring blade 14 Support base (base)
17 Supporting part 18 Height adjusting means 19 Air spring 21 Pin (shaft)
24 level meter (detection means)
25 plates (spacing piece)
26 Torque detector (detection means)
S Object to be processed T Transport direction

Claims (4)

An indirect heating type drying device that heats and dries while conveying a workpiece in a predetermined conveyance direction,
A main body that is supplied with the workpiece and performs a drying process;
A support mechanism provided on both sides of the main body in the transport direction,
The support mechanism is provided between a support part that rotatably supports the main body part around an axis along a direction orthogonal to the transport direction at an upper part, and between the support part and a base surface. An indirect heating type drying apparatus comprising a height adjusting means for adjusting the thickness.   The indirect heating type drying apparatus according to claim 1, wherein the height adjusting unit includes an air spring.   The indirect heating type drying apparatus according to claim 1, wherein the height adjusting means has a stackable interval holding piece which can be detached. Detecting means for detecting at least one of an amount of the object to be processed in the main body and a flow state of the object to be processed;
The indirect heating type drying apparatus according to claim 1, further comprising a control unit that controls the height adjusting unit based on a result detected by the detection unit.

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