JPH1123151A - Wet object drier, and wet goods drying method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable the reduction of processing cost by continuous processing, and easily transform a processing object into a powder without carbonizing it and without making it massive. SOLUTION: A wet object is introduced into a rotary drum 5, and is mixed in the massive body of a ceramic boll B, and they are agitated, and an axial flow is made in one direction while making the massive body exchange heat with the wet object, and the massive body is processed continuously by refluxing the massive body to the flow start section. A reflux means 37 is made of a reversely wound spiral vane body 38. The carbonization is suppressed by adjusting the quantity of supplied heat and the quantity of introduced processing object alternately, and adding batch-type element into a continuous flow.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a wet drier and a method for drying the same. More specifically, wet garbage and sludge are treated and discarded, or surplus sludge treated by the activated sludge method is dried and converted into a powdery form to be taken out and produced for recycling. The present invention relates to a material dryer and a method for drying the same.

[0002]

2. Description of the Related Art It is preferable that sludge and garbage are dried, reduced in volume, and disposed of. Excess sludge generated when the sludge is treated by the activated sludge method is further dried and reproduced as useful substances such as feed and fertilizer. However, such excess sludge has a property that it is difficult to dry, so that it is usually incinerated.
Incineration produces ash and is not suitable for recycling.
The treatment of the ash is the next problem.

A drying apparatus for drying such a sludge which is difficult to dry and taking it out as a powder is developed and known by the present inventors. In this dryer, the rotating drum or a disk-shaped body integrated with the rotating drum is heated by steam passing through the inside. Heat is exchanged with the wet sludge on the surface of the disk-like body thus heated. In this case, there has been a problem that the dried product hardly adheres to the surface of the plate-like body and adheres thereto, and the drying process cannot be continued unless the material is peeled off.

A means for solving such a problem of sticking is known in Japanese Patent Application Laid-Open No. 6-182322.
In the processing method of this drying device, heat is exchanged between a myriad of masses such as ceramic balls, so that the dried mass is joined to the mass. However, since the clumps violently and constantly rub against each other, the attached matter is peeled off and powdered. The ball type dryer known in the above publication cannot perform continuous processing and is of a batch type.

[0005] For this type of drying apparatus, it is particularly desired that the processing cost is extremely reduced by shortening the processing time.

[0006]

SUMMARY OF THE INVENTION The present invention has been made based on such a technical background, and achieves the following objects.

SUMMARY OF THE INVENTION An object of the present invention is to provide a wet dryer and a method for drying the same, which can reduce the processing cost by continuous processing.

Another object of the present invention is to provide a wet-dryer and a drying method for the same, which can be processed at a high speed by a continuous process so that the cost can be reduced.

Another object of the present invention is to provide a wet substance dryer which adheres to the periphery of a circulating mass and dries the wet substance, thereby increasing the drying efficiency and extremely reducing the processing cost, and its drying. It is to provide a method.

Still another object of the present invention is to provide a wet process which can be easily pulverized without carbonization, has a high heat exchange rate, enables continuous treatment, and can extremely reduce the treatment cost. A product dryer and a method for drying the same.

Still another object of the present invention is to easily form powder having a water content of 10 to 15% without carbonization, to have a high heat exchange rate, and to extremely reduce the processing cost by continuous processing. And a method for drying the same.

[0012]

Means for Solving the Problems To solve such problems, the following means are employed. The wet material dryer and the drying method according to the present invention include a rotating body having a rotating internal space. A large number of heat-resistant masses are introduced into the rotating body. The lump may have any outer shape, but is preferably a sphere having a maximum surface area ratio. A material that is resistant to heat, has high mechanical strength, high abrasion resistance, high heat capacity, and high heat retention is preferable, and ceramics are particularly preferable from this viewpoint.

[0013] Such a mass is preheated. That is,
The mass is heated prior to the introduction of the sludge. The mass can be heated not by steam but by hot air generated by a gas burner using petroleum, kerosene or heavy oil, or hot air of waste heat can be used. The introduction and reuse of various exhaust gases into the rotating body can reduce operating costs.

[0014] Between the high-temperature mass and the wet material,
Heat exchange takes place. The moisture content of the dried product is 10 to 15
%. Such a dried product sticks to the surface of the mass and adheres hard. Since the blocks have a large surface area sliding with each other and receiving an impact, the hardly adhered dried material is efficiently peeled off and powdered.

The agglomerates form an axial flow that travels slowly in the rotating body. The axial flow is directed in the direction of the axis of rotation of the rotating body. The axial flow, which is a large part of the return flow path, is formed on both the outward path and the return path. The axial flow in the outward path may be inclined so that the lower position portion of the rotating body forms an axial flow by the action of gravity, and the blade for forming the axial flow having a gentle inclination to form a gentle flow in the axial direction. It may be formed on the inner peripheral surface of the rotating body.

The lump is refluxed from the downstream side to the upstream side, after the dried matter mainly separated in the separation section is separated. Reverse spiral blades are used for reflux.
The reverse spiral blade is provided substantially at the position of the center line of the rotating body, and includes the rotating body and the body.

The object to be processed is continuously introduced into the rotating body. Most of the material is powdered only when the object to be processed is peeled off from the lump, and only the powdered material is separated from the lump and discharged from the discharge port, so that it is possible to continuously introduce the processed material. . Part of the powdered powder collects in the lower part of the rotating body. Such a part is discharged to the outside by gravity from a mesh-like part formed in a part of the rotating body. Another part of the powder is collected by being guided to the cyclone by the airflow in the rotating body. Experiments show that the amount of powder recovered in the cyclone is about two-thirds of the total
Sometimes it becomes.

The forward flow axial flow is adjusted by the flow rate adjusting means. The flow rate is preferably adjusted by means for restricting the flow, for example, the height of the weir in the radial direction, the angle with respect to the axial direction, the degree of opening / closing of the weir component, and the like. By such an adjustment, it is possible to optimally cope with various dried articles and the same dried article having different moisture contents. It is preferable to provide a water wheel type scraping means for scraping the lump at a position below the rotary body to the entrance of the reverse rotating axial flow rotating blade at the turn-back portion which turns back from the outward route to the backward route.

[0019]

Next, an embodiment of the present invention will be described. 1 and 2 are a front sectional view and a side view, respectively, showing an embodiment of a wet dryer and a drying method thereof according to the present invention. A plurality of driven rollers 2 are rotatably supported on a base 1. A rotating drum 5 is rotatably supported by the driven roller 2. The rotation axis of the rotating drum 5 is determined by the position of the driven roller 2. A drive motor 3 is provided on the base 1. The drive motor 3 is variable speed but can rotate at a constant speed.

A large-diameter sprocket 4 is mounted coaxially on the rear surface of the rotary drum 5. A chain 10 extends between a sprocket on the output shaft of the drive motor 3 and a sprocket 4 on the rotary drum 5. The rotating drum 5 includes a rotating drum main body 6 and a winding ring 7.

The winding ring 7 is, as shown in FIG.
It is supported in a radial direction by a large number of support plates 8. The winding ring 7 directly supported by the driven roller 2 reinforces the support structure for supporting the rotating drum main body 6 and also blocks heat transfer to the drive unit. The front end (the right end in FIG. 1) of the rotating body 6 is closed by a front lid 9.

The rear end of the rotary drum body 6 is closed by a conical lid 12. The conical lid 12 is integrally fixed to the rotating body 6. That is, the conical lid 12 is fixed to the rotating body 6. A hopper 13 is fixedly provided on the base 1. The hopper 13 has an input port 15a at the upper end. A supply spiral conveyor 14 passes through the hopper 13. Spiral conveyor 14 for supply,
It is rotationally driven by a supply motor 15 via a sprocket and a chain.

A heat source 16 is provided outside the rotating drum main body 6 and is fixed on the base 1. The heat source 16 is a gas,
It is a burner that uses petroleum, etc. as fuel. Hot air supply pipe 17
Are connected to the burner 16. The distal end portion of the hot air supply pipe 17 penetrates through the conical lid 12 and protrudes into the rotary body 6. The spout at the tip of the hot air supply pipe 17 is
It faces diagonally downward. The rotating trunk body 6 includes the rear bulkhead 1
8 and the front partition 19, the chamber is divided into three chambers, namely a main drying chamber 21, a sub-drying chamber 22 and a sorting chamber 23.

On the inner peripheral surface of the main drying chamber 21, a plurality of first gentle inclined axial flow blades 24 extending substantially in the axial direction are mounted. The first gentle-inclined axial flow blade 24 has a rotation axis L
And generally parallel to the emission plane, but at a slight angle to the emission plane. First
The gently inclined axial flow blade 24 can be formed of one having a slight angle and one having no angle.

As shown in FIG. 4, a plurality of second gentle inclined axial flow blades 27 extending substantially in the axial direction are attached to the inner peripheral surface of the sub-drying chamber 22. The second mildly inclined axial flow blade 27 includes a radiation plane including the rotation axis L, is parallel to the radiation plane, but has a slight angle with respect to the radiation plane. The first moderately inclined axial flow blade 24 can be formed of one having a slight angle and one having no angle.

As shown in FIGS. 1 and 4, the rear partition 18 is provided with a flow rate adjusting means 32. The flow adjusting means 32 includes a guiding body 32a and a flow adjusting plate 32 fixed movably in a radial direction with respect to the guiding body 32a.
b is provided. The main body for guidance 32a includes a bottom plate 32c.
(Depending on the rotational position, it is located inside as shown in FIG. 4).

An outlet 32d is formed in the front plate of the guiding body 32a. The radial height of the front side plate of the guidance main body 32a is formed to be higher than the radial height of the rear side plate of the guidance main body 32a. The flow rate adjusting means 32 includes a lid member 32f on the center side in the radial direction. When the flow rate adjusting means 32 further rotates from the position shown in FIG. 1 and moves to the upper position where the flow rate adjusting means 32 is inclined obliquely, the material to be dried flows into the inflow port 32e of the guiding main body 32a and the outflow port 32d is moved. Opening 1 of the rear partition 18
It is guided and discharged to the sub-drying chamber 22 through 8a.

The flow control plate 32 approaching the horizontal position
The outside surface of b is inclined rearward at that position. The object on the inclined surface flows down and is returned into the rotary drum. The flow rate adjusting plate 32b is fixed by a bolt 32g so as to be movable in the radial direction, and the opening of the inflow port 32e is adjusted by the fixing position.

The opening of the inflow port 32e is controlled by the flow control plate 32b.
Is variable by adjusting the elevation in the radial direction, and the flow rate of the apparatus system is adjusted. The flow rate adjusting means 32 also functions as a flow restricting member for an axial flow in which an object flows axially forward on a floor portion formed during rotation of the lower portion of the rotating drum main body 6,
In this sense, a weir is formed. The outflow guide means 32 having exactly the same structure as the outflow guide means 32 attached to the rear bulkhead 18 is also attached to the front partition wall 19. It is preferable that a plurality of flow rate adjusting means 32 are provided also in the rotation direction.

As shown in FIG. 1, the rear partition wall 18 and the front partition wall 19 have central holes 18a, 1 that share a rotation axis L.
9a is open. Central holes 18a, 19a
A recirculation means 37 is passed coaxially. Reflux means 37
Is the main drying room 2 from the sorting room 23 via the sub drying room 22.
Extends to one. The reflux means 37 includes a cylindrical reverse-wound spiral blade body 38 and a reverse-wound spiral blade 39. The diameter of the reverse-wound spiral blade body 38 is
a, sufficiently smaller than the diameter of 19a.

The reverse spiral wing body 38 is supported by the front wall 9 and other suitable means 40. The reverse spiral spiral blade main body 38 is a cylindrical body having countless small holes 41 formed on the surface. The rear end is open. The reverse-wound spiral blade 39 spirally extends over the entire length of the reverse-wound spiral blade body 38 and extends. The reverse winding means a winding method in which the object in the reverse spiral spiral blade body 38 flows backward.

FIG. 5 is an oblique projection view showing the inside of the rotary drum main body 6 as seen through. An introduction guide gutter 42 is fixedly provided on the front lid 9 at the leading end of the reverse spiral spiral blade body 38. At the head of the reverse spiral spiral blade body 38,
A notch is formed, and an inlet 38a through which an object can enter is formed. The introduction guide gutter 42 extends in the radial direction from the central area and reaches the inner peripheral surface of the rotating body 6.

The introduction guide gutter 42 has a portion 42a for raising the portion orthogonal to the front cover 9 and a portion 42 for preventing the fall parallel to the front cover 9.
b. Each time the introduction guide gutter 42 makes one revolution around the same body as the rotating drum main body 6, the drying target gathered in the lower part of the sorting chamber 23 can be scraped up and guided into the reverse-wound spiral blade main body 38. , Has the effect of a water wheel.

A small hole 45 (FIGS. 1 and 5) is formed in the entire circumference of the cylindrical body where the rotary drum body 6 forms the sorting chamber 23. Below the sorting chamber 23, a discharge passage 46 for guiding and discharging the powder spilling from the sorting chamber 23 is provided.

As shown in FIG. 3, a large number of ceramic balls B, which are spherical masses, are introduced into the main drying chamber 21. The ceramic balls B are distributed entirely in the lower part in the rotating drum in the initial state. The variable constant speed motor 3 is driven to rotate the rotary drum 5, ignites the heat source 16 and introduces hot air into the rotary drum 5 via the gas supply pipe 17. The hot air raises the temperature of the ceramic ball B to about 90 ° C.

The temperature of the ceramic ball B uniformly rises to about 90 ° C. while being agitated mainly by the first gentle axial blade 24 at the bottom of the main drying chamber 21. If the temperature rises in this way, the main drying chamber 2
An excess sludge having a high water content, which is a material to be treated, can be introduced into the inside 1 through the supply spiral conveyor 14. The excess sludge and the ceramic balls B are mixed and stirred together.

Heat exchange is performed between the surplus sludge and the ceramic balls B. The mixture is raised by the first gentle-inclined axial flow blade 24, falls on the way, and returns to the bottom. Upon receiving the heat of the preheated ceramic balls B, the water content of the excess sludge evaporates, and the water content decreases. Most of the heat exchange is performed in the main drying chamber 21 to which the ceramic balls B are supplied with heat.

While being agitated by the first gentle-inclined axial-flow blades 24, the mixture moves forward while forming an axial flow at a slow speed by receiving a part of the axial thrust. The forward direction is the right direction in FIG. During the stirring and mixing, the surplus sludge is dried hard and sticks to the surface of the ceramic ball B.

In such a state, the ceramic ball B
While the flow is restricted by the flow rate adjusting means of the rear partition 18 rotated to the bottom position, the main drying chamber 21 passes through the inlet 32e of the outflow inducing means 32, that is, passes over the weir, so that the secondary drying chamber 22 Is transported to and invaded. Also in the secondary drying chamber 22, drying proceeds by the heat stored in the ceramic balls B. The main drying room 21 among the secondary drying rooms 22
In the same manner as in the above, the mixture forms an axial flow while being stirred by the second gentle inclined axial flow blade 27 and proceeds forward, and further undergoes a drying action during the progress. Similarly, the material to be dried is carried into the sorting room 23 from the heavy drying room.

The ceramic ball B having the dried excess sludge adhered to the surface thereof enters the sorting chamber 23 and is spirally wound through the introduction guide gutter 42 while being scraped up by the introduction guide gutter 42. It is guided into the blade body 38. The reverse spiral spiral blade main body 38 rotates in the same manner as the rotary drum 5. The ceramic ball B receives a reverse propulsion force by the reverse spiral spiral blade 39 in the reverse spiral spiral blade main body 38, and has an opposite axis opposite to the axial flow direction in the main drying chamber 21 and the secondary drying chamber 22. Form a flow.

In this way, the water flows backward and flows back into the main drying chamber 21 from the opening at the rear end of the reverse spiral spiral blade body 38. The ceramic ball B circulates by the forward axial flow and the backward axial flow. Excess sludge is subjected to a drying action, and the water content is reduced to 10 to 15%.

The excess sludge having a reduced water content sticks more and more hardly to the ceramic balls B, but is vigorously stirred and the adjacent ceramic balls B rotate relative to each other to dry the surface. Things rub. Such abrasion occurs violently during the reverse propulsion by the reverse spiral wings 39.

The dry matter in the form of a spherical layer that rubs in this way is abraded or crushed with each other and powdered and peeled off from the ceramic ball B. The powder thus peeled off falls out of the small hole of the reverse spiral spiral blade main body 38 and is removed from the main drying chamber 21.
And is guided to the sorting chamber 23 on the axial flow.
The powder guided to the sorting chamber 23 falls when it is at a lower position from the myriad of small holes 45 formed in the cylindrical body, which is the sorting chamber 23, and is discharged from the discharge path 46.

The main function of the secondary drying chamber 22 is to evaporate water.
It is transpiration. This evaporation is performed by the heat of the ceramic ball B, and the temperature of the ceramic ball B rapidly decreases. There is substantially no drying in the sorting room 23, and the sorting function is mainly performed. In the main drying chamber 21, the organic substance evaporated in the entire drying chamber is directly burned by the heat source 16, so that the odor is eliminated. The heat of the hot air is consumed to raise the temperature of the ceramic balls B without causing the excess sludge to carbonize.

The proportion of the ceramic balls B and the excess sludge to be dried is an important factor for efficient drying. According to the experiments, the ceramic balls B are in excess of 2.5 to 3.
Preferably it is 5 times. When the ratio of the ceramic balls B is smaller than the above ratio, only the sludge is collected and formed into a ball, so that the drying time becomes longer. There is not much significance in making the ratio of the ceramic balls B larger than the above ratio.

In order to increase the surface area at the same weight ratio, the diameter of the ceramic ball B may be reduced. The ceramic ball B is excellent in that it emits far-infrared rays and heat penetrates well into moisture to improve drying efficiency and is less likely to be worn. be able to.

An inexpensive fuel can be used for the heat source. By controlling the temperature of the main body to a low temperature of about 100 ° C., there is no need to use a heat-resistant material for the main body of the rotary drum, and the drying apparatus is inexpensive and small. By adjusting the number of revolutions of the rotating body, the quantity and size of the balls, the opening degree of the feed inlet 32, the change of the nozzle of the burner, etc., it is possible to perform drying optimally for various objects to be dried.

As shown in FIG. 1, a part of the circulating hot air in the rotating drum main body 6 is introduced into the cyclone 51 via a suction fan. The powder centrifuged in the cyclone, which is a centrifugal dust collector, is collected in a dust collecting chamber 52 below the cyclone 51. The collected powder is discarded as garbage or recycled. The dryer according to the present invention is also used as a powder manufacturing machine.

[0049]

[Other Embodiments] In the embodiment of the present invention, the recirculating means 37 is arranged at the center of the rotary drum 5. However, the ceramic ball B is not
Other reflux means may be used as long as they return to the vicinity of the drying material charging port. For example, there is a method in which the ceramic balls B are taken out of the rotating drum 5 and returned to the original state by a transfer means such as a conveyor.

[0050]

According to the wet substance dryer and the wet substance drying method of the present invention, since the lump and the powder are recirculated and only the powder peeled off from the lump is collected, the wet substance can be continuously added. As a result, continuous processing is possible. This continuous processing can extremely reduce the processing cost. Powderization that can be easily post-processed without carbonization can be easily performed. The heat exchange rate is high and fuel economy can be reduced. The cost is low because the apparatus is simplified. Furthermore, cost reduction is promoted because high-speed processing is possible by continuous processing.

[Brief description of the drawings]

FIG. 1 is a front sectional view showing Embodiment 1 of a wet drier according to the present invention.

FIG. 2 is a left side view of a rotating body portion.

FIG. 3 is a sectional view taken along the line III-III of FIG. 1;

FIG. 4 is an oblique axis projection view showing a flow rate adjusting means.

FIG. 5 is an oblique axis projection view showing the inside of the rotating drum.

[Explanation of symbols]

 Reference Signs List 5 rotating drum (fuselage) 6 rotating drum body (fuselage) 6 heat source 13 hopper 21 main drying chamber 22 auxiliary drying chamber 23 sorting chamber 24 first axial blade (one-way means) 26 second 1 spiral blade (one-way means) 27 ... second axial blade (one-way means) 29 ... second spiral blade (one-way means) 32 ... flow rate adjusting means 37 ... recirculation means 38 ... reverse-wound spiral blade body (reflux means) 41 ... Small hole 45 ... Small hole L ... Rotating axis center line B ... Ceramic ball (mass)

Claims (10)

[Claims] 1. A body, into which a wet substance is introduced and rotated, and a large number of heat exchange masses which are agitated and move in the body and have high heat resistance, wherein the mass body is formed by the wet mass. Reflux means for flowing in one direction while exchanging heat with the object, and further recirculating the lump flowing in one direction to a portion where the mass starts to flow, the one-way return path formed by the return means is a return path, A wet-dryer characterized by being formed from an outward path. 2. The wet substance dryer according to claim 1, wherein the respective flows in the return path and the outward path are axial flows substantially parallel to the rotation axis of the body. 3. The flow according to claim 1, wherein the respective flows of the return path and the forward path are axial flows substantially parallel to the rotational axis of the body, respectively, and the return path is turned back from the forward path to the return path. Wet drier characterized by being provided with folding means. 4. The wet-dryer according to claim 1, wherein the return path is formed by a spiral blade having a rotation axis that substantially shares the rotation axis of the body. 5. The apparatus according to claim 1, further comprising one-way means for generating said one-way flow, wherein said one-way means is an axial flow for flowing said mass in a direction of a rotation axis of said body. A wet drier characterized by being a blade. 6. The wet drier according to claim 1, wherein an adjusting means for adjusting a flow velocity of the mass is provided on the return path. 7. The wet drier according to claim 6, wherein the adjusting means is a weir. 8. The wet body according to claim 6, wherein a lower portion of the body is inclined in a direction of a rotation axis of the rotating body to form a flow in the return path by gravity. Drying machine. 9. Rotating a body having an inner space, forming a circulating flow of a large number of heat exchange masses which are agitated and move in the body and resistant to heat, in the body. Supplying hot air into the body, mixing the mass and the wet material in the body, bringing them into contact with each other, and stirring the mixture; drying the surface of the mass and frictionally contacting each other with the wet material. Discharging the powder which is dried and detached from the mass from a part of the annular flow path to the outside of the body. 10. The wet substance according to claim 9, further comprising: introducing the hot air into a cyclone from a part of the return path, and collecting the powder in the cyclone. Drying method.