JP4445152B2 - Structure for stirring and transferring workpieces in a rotary drum dryer - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a dryer used for pretreatment of municipal waste in RDF manufacturing facilities, municipal waste gasification and melting facilities, etc., and in particular, low-quality waste having a high water content is effectively modified in the dryer to improve drying efficiency. The present invention relates to a stirring and transporting structure that can be used.
[0002]
BACKGROUND OF THE INVENTION
Recently, garbage such as household waste and industrial waste discharged in the city is dried and reused as, for example, RDF power generation as solid fuel. In addition, there is a rotary drum type dryer as a dryer used at that time, which is provided with a rotary shaft penetrating both openings in a cylindrical rotary drum horizontally disposed, and this rotation is further provided. The shaft is provided with a blade. Also, a lifter is provided on the inner surface of the rotating drum, and the municipal waste is stirred and dispersed by the vane plate and the lifter.
[0003]
Using such a rotary drum type dryer, a moisture content of 60 to 70% W.S. When drying municipal waste of B or higher, the low-quality waste has low dispersibility and fluidity, so that there is a problem that the contact between the low-quality waste and the hot air is not suitably performed and the drying efficiency is lowered. It was.
And as a countermeasure for this, it is also possible to increase the rotation speed of the stirring blade provided for the purpose of stirring the object to be processed, but the limit is because string-like dust tends to be entangled with the rotating shaft. And the effect was not sufficient.
[0004]
Therefore, an attempt has been made to improve the state in which the moisture content is lowered by mixing the object to be treated (residual waste) whose moisture content is reduced in the rotating drum and mixing it with the low-quality waste just entered. Yes. In other words, the object to be processed (urban waste) thrown into the dryer moves in the direction of the discharge port as the drying proceeds, and the object to be processed (residual waste) located on the discharge port side is moved to the input port side. To be transported.
As a specific method for this purpose, the shape of the lifter is made such that the object to be treated (stagnant dust) is dropped to the inlet side, or the shape of the blade plate is charged to the object to be treated (residual dust). It was done to make a shape that radiates to the mouth side.
However, according to the lifter, the object to be treated (residual dust) having a high water content located in the lower layer portion is returned, and the reforming efficiency of the low-quality dust is lowered. Further, according to the vane plate, the object to be processed (stagnant dust) released toward the inlet side is pushed back to the outlet side by the hot air supplied from the inlet side, and the low-quality waste is modified. Quality efficiency will decrease. For this reason, further improvement in reforming efficiency has been desired.
[0005]
[Technical issues for which development was attempted]
The present invention has been made in view of such a background, and it is possible to reform low-quality waste having a high water content with high efficiency in the dryer, and thus improve the drying efficiency of low-quality waste. This is an attempt to develop an agitating and transferring structure for an object to be processed in a novel rotary drum dryer capable of handling the above.
[0006]
[Means for Solving the Problems]
That is, the rotary drum type dryer according to claim 1 stirs the object to be processed supplied from the inlet of the rotary drum by the rotation of the rotary drum and the rotation of the blade plate provided on the rotary shaft arranged in the rotary drum. In the rotary drum type dryer in which the dried object is sequentially dried from the discharge port in contact with the hot air, the rotary shaft is a horizontal line passing through the center of the rotary drum in a front view. a more downward, and is intended to position the point which does not overlap with the vertical line passing through the center, also the the rotary shaft are those spiral vanes comprises al is, the spiral vanes, the height of the threads Is set to be shorter than the length of the vane plate, and only the surface layer portion of the object to be processed, which has been dried and reduced in water content , is positioned on the inner peripheral surface of the rotating drum by the spiral blade. Throw By transferring to the mouth side, the object to be treated whose water content has been reduced can be mixed with the object to be treated which has just been added, and the water content of the object to be treated located near the inlet can be reduced. It is characterized by having been configured.
According to the present invention, even when low-quality waste having a high water content is supplied into the rotary drum, the water content is reduced by reforming in the vicinity of the inlet, so that the dispersibility is improved and contact with hot air is achieved. Is preferably performed to improve the drying efficiency.
In addition, a necessary and sufficient time can be ensured for the time during which the object to be processed put in the rotating drum stays in the drying drum, and drying is performed effectively.
Furthermore, the spiral blade formed on the rotating shaft can prevent the long dust having an apparent outer peripheral length of the spiral blade or less from being entangled with the rotating shaft.
Further, since only the debris having a low water content constituting the surface layer portion of the workpiece to be processed located on the inner peripheral surface of the drum is transferred, it is possible to effectively reform the low-quality dust in the vicinity of the inlet.
The above-described problems can be solved by using the requirements described in these claims as means.
[0007]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, a stirring and transferring structure for an object to be processed in a rotary drum dryer according to the present invention will be described based on the illustrated embodiment. In the figure, reference numeral 1 denotes a rotary drum type dryer, which is provided with a cylindrical rotary drum 2 that is rotatably disposed horizontally, and is rotatably provided across the longitudinal direction in the rotary drum 2. Which are supported by a loading machine frame F1, a discharge machine frame F2 and a support roller R.
In this specification, the direction of the rotary drum dryer 1 is defined as follows, and the traveling direction of the municipal waste D as the object to be processed, that is, the discharge port 21 side of the rotary drum 2 is defined as the front. The opposite side, that is, the inlet 20 side is defined as the rear.
Further, in the following description, the municipal waste D, which is an object to be processed by the rotary drum dryer 1, stays between the inlet 20 and the outlet 21 in the rotary drum 2 and is dried. This is referred to as staying garbage D1.
[0008]
Hereinafter, each member constituting the rotary drum dryer 1 will be described. The rotary drum 2 is a cylindrical member, and is rotatably mounted on a support roller R provided on the base B. The opening portions on both sides are closed by the input side cover body 2A and the discharge side cover body 2B, and the rotary drum 2 can rotate at the boundary between the input side cover body 2A and the discharge side cover body 2B and the rotary drum 2. It is sealed to become.
An input port 20 and a hot air blowing port 22 are formed in the input side lid 2A, and a discharge port 21 and an exhaust port 23 are formed in the discharge side cover 2B.
As shown in FIG. 2, a flat ring-shaped inlet weir 24 is provided in the rotary drum 2 on the inlet 20 side, while a flat ring-shaped outlet weir 25 is also provided on the outlet 21 side. Provided. The inlet weir 24 and the outlet weir 25 are both for regulating the outflow amount of the workpiece. In particular, the height dimension (the difference between the outer diameter and the inner diameter) of the outlet weir 25 is within the rotary drum 2. The staying amount of the staying dust D1, which is the object to be processed, is determined.
[0009]
As shown in FIG. 3, four angle-shaped lifters 26 are provided on the inner surface of the rotary drum 2 as an example at intervals of 90 ° in front view. The height dimension of the lifter 26 is set to 1/3 or less of the height dimension of the outlet weir 25, for example, and the upper part is pointed to the inner peripheral surface from the center side of the rotary drum 2. It is made to incline so that the skirt spreads toward the side.
[0010]
Here, the structure for rotationally driving the rotary drum 2 will be described. As shown in FIG. 1, this structure is such that the chain 27 is wound around a gear provided on the outer peripheral surface slightly on the input side near the center of the outer surface of the rotary drum 2. The rotary drum 2 is rotationally driven by a drive motor M1 provided on the base B.
[0011]
Next, the agitation transfer mechanism 3 will be described. In this structure, as shown in FIGS. 1, 3, and 4, a spiral blade 31 is formed with respect to the rotating shaft 30 and a blade plate 32 is substantially perpendicular to the rotating shaft 30. The rotary shaft 30 is rotatably supported by a bearing 33. The rotary shaft 30 is disposed so as to penetrate the rotary drum 2 in the longitudinal direction thereof. As an example, the rotary shaft 30 is below a horizontal line passing through the center of the rotary drum 2 in a front view as shown in FIG. , And a position that does not overlap with a vertical line passing through the center.
[0012]
Further, the spiral blade 31 is formed along the longitudinal direction with respect to the side peripheral surface of the rotating shaft 30 and is formed so as to advance from the front to the rear as the rotating shaft 30 rotates. . Although FIG. 4 shows the spiral blade 31 formed as a right-hand thread, it can also be formed as a left-hand thread.
Then, the width of the spiral blade 31, that is, the height of the thread is set shorter than the length of the blade plate 32 as shown in FIG. 3, and is located on the inner peripheral surface of the rotary drum 2. It is set so that only the low-moisture and light-weight stored dust D1 that is located in the surface layer portion of the stored dust D1 can be transferred.
Moreover, the pitch is set so that it may become narrow as it goes to the back from the front as an example, and this is made to respond | correspond to the attachment pitch of the blade board 32. FIG.
[0013]
The vanes 32 are provided radially at intervals of 120 ° as viewed from the front as an example, and the mounting pitch is set so as to become narrower from the front to the rear.
[0014]
Here, the structure for rotationally driving the rotary shaft 30 will be described. As shown in FIGS. 1 and 2, the input-side machine frame F1 placed on the base B on the rear side of the rotary drum 2 is provided with a drive motor M2 and rotated. The drive of the drive motor M2 is transmitted to the rotary shaft 30 by winding a chain 35 around sprockets 34 provided on the shaft 30 and the output shaft of the motor M2, respectively.
[0015]
Further, a charging device 4 for supplying municipal waste D, which is an object to be processed, into the rotary drum 2 is provided on the charging-side machine frame F1. In this embodiment, a hopper and a screw conveyor are combined as an example. Applied.
[0016]
The structure for stirring and transferring the workpiece in the rotary drum dryer 1 of the present invention is configured as described above as an example, and the operation mode thereof will be described below. First, the rotating drum 2 and the rotating shaft 30 are rotated counterclockwise in FIG. 3, and hot air is blown into the rotating drum 2 from the hot air blowing port 22, and then municipal waste D is introduced into the charging device 4. Is fed into the rotary drum 2 from the inlet 20.
Then, as shown in FIG. 5, the municipal waste D (retained waste D1) is agitated by the blade plate 32 in the agitation transfer mechanism 3 and is scattered in the rotary drum 2 and comes into contact with the hot air to evaporate the moisture and increase the moisture content. Further, the lifter 26 lifts a part of the accumulated dust D1 and proceeds to the discharge port 21 side while promoting stirring. Then, as shown in FIG. 6, the staying dust D <b> 1 reaching the outlet weir 25 gets over this and is discharged from the discharge port 21.
[0017]
At this time, according to the present invention, the spiral blade 31 is formed on the rotary shaft 30. Therefore, the spiral blade 31 transfers the accumulated dust D1 that has been dried and has a reduced moisture content to the inlet 20 side. Yes, the debris D1 having a reduced moisture content is mixed with the municipal waste D that has just been thrown in, so that the moisture content of the debris D1 located in the vicinity of the inlet 20 can be reduced.
That is, as shown in FIG. 6, the accumulated dust D1 located on the inner peripheral surface of the rotating drum 2 has a high moisture content in the lower layer due to a difference in specific gravity, while a low moisture content in the upper layer. Therefore, the spiral blade 31 is capable of transferring only the upper staying dust D1 to the inlet 20 side.
[0018]
As described above, according to the present invention, even when low-quality waste having a high water content is supplied into the rotary drum 2, the dispersibility is improved because the water content is reduced by reforming in the vicinity of the inlet 20. The contact with hot air is preferably made, and the drying efficiency is improved. In other words, the low-quality waste having a high water content tends to dry up only the surface layer in contact with the hot air in the rotary drum 2, and the drying tends to be unbalanced. However, this can be avoided.
Further, part of the staying dust D1 located in the rotating drum 2 circulates in the longitudinal direction of the rotating drum 20, so that the staying time in the drying drum 2 becomes longer, and as a result, drying is performed effectively.
Furthermore, the spiral blade 31 formed on the rotary shaft 30 can prevent long dust having an apparent outer peripheral length of the spiral blade from getting tangled with the rotary shaft 30. Driving can be continued smoothly.
[0019]
【The invention's effect】
According to the present invention, low-quality waste having a high water content can be reformed with high efficiency in the rotary drum dryer 1, and the drying efficiency of low-quality waste can be improved.
[Brief description of the drawings]
FIG. 1 is a side view showing an embodiment of a rotary drum dryer according to the present invention.
FIG. 2 is a front view and a rear view of the same.
FIG. 3 is a cross-sectional front view of a rotating drum.
FIG. 4 is a side view showing an agitation transfer mechanism.
FIG. 5 is a cross-sectional front view showing a state of stirring of stagnant dust by a stirring transfer mechanism and a lifter.
FIG. 6 is a longitudinal side view showing a state of stirring of stagnant dust by a stirring transfer mechanism and a lifter.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Rotating drum type dryer 2 Rotating drum 2A Input side cover body 2B Discharge side cover body 3 Stirring transfer mechanism 4 Input device 20 Input port 21 Discharge port 22 Hot air blowing port 23 Exhaust port 24 Inlet weir 25 Outlet weir 26 Lifter 27 Chain 30 Rotating shaft 31 Spiral blade 32 Blade plate 33 Bearing 34 Sprocket 35 Chain B Base D Municipal waste D1 Dust accumulation F1 Input side machine frame F2 Discharge side machine frame M1 Drive motor M2 Drive motor R Support roller

Claims (1)

The object to be treated supplied from the inlet of the rotary drum is agitated by the rotation of the rotary drum and the rotation of the blade plate provided on the rotary shaft arranged in the rotary drum, thereby bringing into contact with hot air and drying. In the rotary drum dryer that sequentially discharges the processed material after drying from the discharge port, the rotary shaft is below a horizontal line passing through the center of the rotary drum in a front view and a vertical line passing through the center. are those located in non-overlapping locations, also the the rotary shaft are those spiral vanes comprises al is, the helical blade is shorter than the length of the height dimension is the vane of the screw thread a shall, by the spiral vane located on the inner peripheral surface of the rotating drum, by transferring only to inlet side surface portion of the drying proceeds the processing object having a reduced water content, the water content Decline The rotary drum dryer is characterized in that it can mix the processed object and the processed object that have just been added, and reduce the water content of the processed object located near the charging port. Transfer structure of workpieces in

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