JP2001248966A - Dryer for liquid-like sludge or the like - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a dryer for a liquid-like sludge or the like capable of drying a mud-like liquid-like material containing a large quantity of a moisture such as a water content of 90% or more by directly charging the material and reducing an operating cost, a manufacturing cost and size of the dryer by extremely decreasing a heat radiating loss. SOLUTION: A cylindrical metal rotary drum 3 is rotatably disposed at a horizontal rotary shaft 4 as a center in an outer case 2. A combustion chamber 3B is formed in the drum 3. A sludge storage tank 10 having a heat exchanger 11 for preheating the liquid-like sludge A is arranged in the case 2. Coating means 12, 13 for continuously coating an outer peripheral wall 3A of the drum 3 with the sludge A are provided. A scraper 14 for scraping off the sludge A is arranged under the drum 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a heating type drying method suitable for drying liquid sludge having a very high water content (for example, about 95% water content), such as sewage sludge, industrial wastewater sludge, and livestock manure. It concerns the device.

[0002]

2. Description of the Related Art With the spread of sewage systems, the amount of sewage sludge generated in sewage treatment plants, polymer wastewater sludge from factories, and livestock sludge representing cattle dung and swine dung is increasing year by year. Most of these sludges are incinerated after being concentrated, dewatered, and dried, or landfilled in the ocean or land.

[0003] Originally, the treatment of sludge or industrial waste having a high water content as described above must take into account both volume reduction technology and recycling technology.
In any case, the steps of moisture adjustment and drying are inevitable. However, the drying technique requires a lot of cost and has problems such as difficulty in downsizing the apparatus. Generally, a large amount of an additive as a moisture regulator is added to the material to be dried. In addition, the current situation is that the water content is adjusted.

Meanwhile, in the conventional heating type sludge dryer, a method of directly applying heat to the sludge on the conveyor to dry it, put sludge in a horizontal cylinder, rotate the sludge,
A method in which the cylinder itself is heated and dried, a method in which sludge is put in a horizontal cylinder and rotated by a stirrer provided in the cylinder, and a stirrer blade or the cylinder itself is heated and dried, in a casing filled with sludge. Vacuum, heating and drying from the outside, sludge placed on a vertically arranged multi-stage disk, heating while sequentially falling to the lower stage, drying, and applying sludge in a vertical cylinder and applying sludge from outside A method of heating and drying is adopted.

As another prior art, there is a drying apparatus described in Japanese Patent Application Laid-Open No. 11-351746 filed by the present applicant. This device partitions the outer peripheral wall of the rotating drum arranged in the housing at equal intervals in the circumferential direction to form a mounting portion for the object to be dried, and continuously inputs the object to be dried to the mounting portion described above, A structure is provided in which the object to be dried is dried by heating the inside of the rotating drum via a combustion device.

[0006]

However, the above-mentioned conventional drying apparatus has various problems as follows.
In other words, in the conveyor system of the heating type sludge dryer, the heat loss increases due to the large heating space, the generation of undried sludge due to the uneven heating, and the odor sealing becomes large because the equipment is large for the throughput. In addition, there is a problem that the manufacturing cost is high, the size of the apparatus is increased, and the machine is easily stopped and damaged due to the accumulation of sludge on the movable part.

[0007] In the cylindrical rotation method, the driving power is increased due to the large rotating portion, dust is generated due to the large amount of sludge moving in the apparatus, and any of sludge injection, odor suction, internal washing water, and drainage is used. Because of the direct contact with the rotating body, the production cost increases due to the complexity of the mechanism, the operating cost increases due to the large external heat dissipation, and it is not possible to take measures against sticking to the inner surface. Is unsuitable.

In the in-cylinder stirrer system, overdried sludge and undried sludge are generated due to uneven stirring, dust is generated due to a large amount of sludge moving in the device, noise is generated by the stirrer, external The large heat release increases the operating cost and makes it impossible to take measures against sticking to the inner surface or the stirrer, so that it is not suitable for high-viscosity sludge.

In the vacuum drying method, an airtight structure against vacuum and a vacuum generator are expensive, and continuous operation cannot be performed because of a batch operation.
There is a problem that a storage facility for securing the capacity for the batch is required, and the production cost and the installation area increase.

In the multi-stage disk system, heat loss is increased due to a large number of heating spaces, clogging is likely due to a long passage of sludge, and sludge is moved using slanting, and is not suitable for high-viscosity sludge. There is a problem.

[0011] In the vertical in-cylinder coating method, the operation cost is increased due to the large external heat radiation, an expensive quantitative sludge supply device is required to apply the sludge to the vertical surface, and this method has possession of sludge. Due to the natural separation type discharge method by evaporation of water, there is a problem that dried sludge with low moisture cannot be produced and only sludge suitable for adhesion to a vertical surface and separation can be handled.

The apparatus described in the above publication has a water content of 8
If the sludge cake is about 0 to 85%, it can be placed on the placing portion on the rotating drum and dried while rotating. However, for example, a liquid material (livestock manure) in which livestock manure such as cow manure and pig manure is mixed with urine has a water content of 95%.
%, The moisture content is extremely high, so even if the drum is dropped on the mounting part directly above the rotating drum, it will not be retained on the mounting part when the rotating drum rotates, but will immediately run off and dry. Can not. Therefore, when the same drier is used to dry a liquid matter having a very high water content in which livestock manure is mixed with manure, it may be subjected to a dehydration treatment or a large amount of an additive as a moisture regulator. It is necessary to reduce the water content in addition to the dried product. For this reason, liquid sludge having an extremely high water content, such as livestock manure, cannot be directly introduced into the apparatus and dried, which is troublesome and increases the cost required for drying.

The present invention has been made in view of the above points, and it is possible to directly input a muddy liquid containing a large amount of water having a water content of about 93% or more, and to dry the liquid. The purpose of the present invention is to provide a drying apparatus for liquid sludge and the like, which can reduce the operating cost by extremely reducing the amount, reduce the manufacturing cost by simplifying the structure and eliminate the need for special accessories, and reduce the size of the apparatus. And

[0014]

In order to achieve the above-mentioned object, a drying apparatus for liquid sludge or the like according to the present invention comprises a rotating drum having a cylindrical metal outer peripheral wall in an outer casing. The rotating drum is rotatable by a driving device, the inside of the rotating drum is formed in a combustion chamber, and the outer peripheral wall of the rotating drum can be heated in the combustion chamber through the combustion device. In the outer casing, a sludge storage tank provided with a heating means (preheating means) for preheating the object to be dried such as sludge is provided, and the object to be dried which has been put into the sludge storage tank and preheated is provided. A pre-heating means for providing a coating means for continuously coating the outer peripheral wall of the rotating drum, a means for scraping off the object to be dried below the rotating drum, and continuously applying the coating material on the outer peripheral wall of the rotating drum; Convert the dried material into conduction heat from the combustion chamber Ri is characterized in that dried indirectly heated.

According to the drying apparatus of the present invention having the above-described structure, even a substance to be dried having an extremely high moisture content which cannot be directly introduced and dried by the apparatus described in the above-mentioned publication without any treatment. It can be poured as it is and dried. In other words, by pre-heating the object to be dried and reducing the moisture content to some extent, the object to be dried is continuously applied in a thin film on the outer peripheral wall of the rotary drum, so that the contact area of the object to be heated with the heat medium is reduced. A large ratio can be adopted, and furthermore, the rotation of the rotating drum in the outer casing minimizes the dissipation of heat to the outside. To the evaporation energy of
It can be dried uniformly in a short time. The object to be dried which has been applied to the outer peripheral wall of the rotary drum and dried by heating is continuously scraped off by the scraping means and collected. In addition, the structure of the whole device is simple and maintenance is easy. In addition, since the material to be dried is applied on the outer peripheral surface of the rotating drum and heated indirectly, the generation of dust is small and there is no need to remove parts. In addition, the rotating drum and the inside of the outer casing can be easily cleaned.

In a preferred embodiment of the present invention, the applying means comprises a pressing roller for thinning and applying the object to be dried, and an object to be dried near a contact position between the pressing roller and the outer peripheral wall of the rotating drum. And a gutter-shaped header for the material to be dried.

According to the drying apparatus of the second aspect, when drying the dried matter containing a large amount of water having a water content of about 95%, such as livestock manure and other raw sludge, before drying, etc. The coating can be continuously and thinly applied on the outer peripheral surface of the rotary drum without any treatment, and can be efficiently dried in a short time.

According to a third aspect of the present invention, an exhaust gas with an odor generated when the object to be dried is preheated in the outer casing is introduced into a combustion chamber in the rotary drum, and the exhaust gas for the combustion chamber is provided. It is desirable to deburn by reburning with a combustion device.

According to the drying apparatus of the third aspect, the odor-containing exhaust gas is burned at a high temperature without providing a separate deodorizing device, thereby making it odorless and harmless.

According to a fourth aspect of the present invention, as the heating means for preheating the object to be dried, exhaust gas discharged from the outer casing is introduced into a combustion chamber in the rotary drum, and the heating means for the combustion chamber is used. A heat exchanger using the exhaust gas after reburning by the combustion device can be used.

According to the drying device of the fourth aspect, when pre-heating a material to be dried such as livestock manure having an extremely high water content,
Part of the heat required for heating and drying can be effectively imparted using waste heat, and for example, frozen livestock manure in cold regions can be dried without using a special thawing device, and drying efficiency can be improved. Can be improved.

According to a fifth aspect of the present invention, the combustion chamber in the rotary drum is provided with a mist separator which removes water from an exhaust gas containing water vapor and odor generated when drying the material to be dried, and then performs combustion. It can be used as a reburning furnace that is made odorless.

According to the fifth aspect of the present invention, the odor gas and the like generated when the material to be dried is dried can be supplied to the combustion chamber as combustion air, and there is no need to separately provide a dedicated combustion chamber. The device becomes simple.

According to a sixth aspect of the present invention, the amount of combustion and the amount of combustion air in the combustion chamber can be adjusted by automatically proportionally controlling the amount of fuel supplied and the amount of combustion air in the combustion device. A burner that is held and has high thermal efficiency can be used. When the drying device of the present invention is incorporated as a part of a series of sludge treatment plants, it is desirable to use a gas regenerative burner including a burner gun, a main body, a honeycomb casing, and a supply / exhaust nozzle in the combustion device.

According to the drying apparatus of the sixth aspect, by controlling the amount of combustion in the combustion chamber proportionally, it is possible to easily adjust the moisture of the object to be dried and the amount of processing. In particular, by using a gas regenerative burner, the amount of waste heat in the exhaust gas can be suppressed extremely low by highly efficient heat exchange between the combustion air and the exhaust gas by the honeycomb casing, and the drying efficiency can be further improved. The use of such a gas stabilizes combustion, makes it easier to adjust the temperature in the rotary drum, and makes it easier to adjust the moisture content of the material to be dried and to automate the operation.

[0026]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a drying apparatus according to the present invention will be described below with reference to the drawings.

FIG. 1 is a central longitudinal sectional view showing an embodiment of a liquid sludge drying apparatus viewed from the front, FIG. 2 is a sectional view taken along line AA of FIG. 1, and FIG. 3 is a sectional view taken along line BB of FIG. FIG. 4 is a left side view of the sludge drying apparatus of FIG.

As shown in FIG. 1, the drying apparatus 1 has a substantially cubic outer casing 2 supported by a plurality of support legs 8, and a cylindrical rotating drum 3 has one end in the outer casing 2 with its one end facing sideways. 3, and a lower end outer peripheral edge portion is rotatably supported by a pair of drum retainers 7, 7 as shown in FIG. A part of the rotary shaft 5 penetrates through the center of one side wall 2a of the outer casing 2 and protrudes outward, and a sprocket 16 is attached to an outer end thereof so as to be integrally rotatable. Above the sprocket 16 and on the left side of the figure, in this example, a variable-speed inverter electric motor 6 is provided with a side wall 2.
The sprocket 15 and the sprocket 16 are disposed on a bracket 2c fixedly mounted on the drive shaft a, and are attached to a drive shaft end of the electric motor 6 so as to be integrally rotatable.
Connected by Further, an exhaust port 26 for discharging dried exhaust gas generated in the outer housing 2 is opened at an upper end portion of a rear wall of the outer housing 2.

The outer peripheral wall (outer peripheral surface) 3A of the rotary drum 3 is a cylindrical body made of a heat-resistant metal such as stainless steel as shown in a partially enlarged view of FIG. The openings on both sides of the rotary drum 3 are closed by a disk-shaped heat insulating material 18 and a disk-shaped heat insulating material 19, respectively.
And is fixed so as to rotate integrally with the rotating drum 3. The heat insulating material 18 on the opposite side is loosely fitted in the support portion 3a of the rotary drum 3 by the drum retainer 7, and is integrally fixed to the other side wall 2b of the outer casing 2,
Between the inner peripheral surface of the support portion 3a and the steel plate holding the outside of the heat insulating material 18, a packing 20 also serving as a bearing is interposed as shown in FIGS.

As shown in FIG. 2, a sludge storage tank 10 is provided integrally with the outer casing 2 on one side (right side) of the lower central portion of the rotary drum 3. As shown in FIG. 1, an input pipe 21 a is piped from the sludge input port 21 into the outer casing 2 so as to face the sludge storage tank 10, and a sludge outlet 24 is provided on the bottom surface of the sludge storage tank 10. As shown in FIG. 2, a multi-tube heat exchanger 11 is loaded in the sludge storage tank 10 and fixed to the outer casing 2 via a gasket (not shown).
Exhaust gas generated from the inside of the rotary drum 3 (combustion chamber 3B) of the drying apparatus 1 is used for the heat exchanger 11, and the exhaust pipe 22 and the exhaust pipe 23 of this exhaust gas are respectively formed on one side surface 2d of the outer casing 2. From the outside. In this example, the heat exchanger 11 provided in the sludge storage tank 10 constitutes a preheating means for the sludge A (see the lower part of FIG. 5).

Above the sludge storage tank 10 in the outer casing 2, a pressing roller 13 is rotatably supported in contact with the outer peripheral wall 3A of the rotating drum 3. In other words, the rotating shafts 13a at both ends of the holding roller 13 are supported on the inner wall surface of the outer casing 2 via bearings (not shown), and the holding roller 13 rotates about an axis parallel to the rotating shaft 5 of the rotating drum 3. I do. Further, the sludge header 12 is disposed immediately above the pressing roller 13, and the lower end of an L-shaped sludge introduction pipe 25 is connected to the upper end of the sludge header 12, and the inlet 25 of the sludge introduction pipe 25 is connected.
a protrudes outward from the side surface of the outer housing 2. The inlet 25a of the sludge introduction pipe 25 is connected to the sludge outlet 24 by a pipe 27a, and a sludge feed pump 27 is provided in the middle of the pipe 27a.

FIG. 5 is a front view showing in detail the means for applying sludge A and the means for preheating. As shown in the figure, the liquid sludge A stored in the sludge storage tank 10 is supplied to the heat exchanger 1.
1, and is fed to the sludge header 12 by the feed pump 27. The sludge A flowing into the sludge header 12 overflows from an upper edge (overflow line) 12b and is guided between the outer peripheral wall 3A of the rotary drum 3 and the pressing roller 13 along the guide wall 12a. , The sludge A is applied to the outer peripheral surface of the rotating drum 3 rotating counterclockwise by the pressing roller 13 rotating clockwise, and the sludge A has a substantially constant thickness.
It sticks to the outer peripheral surface of and rotates. In this example, the sludge header 12 and the pressing roller 13 constitute sludge application means. Reference numeral 38 in FIG. 5 denotes an overflow port of the sludge A stored in the sludge storage tank 10.

At the lower central portion of the rotary drum 3, a tip (upper end) of a scraper 14 as a means for scraping off sludge is provided.
Is brought into contact with the outer peripheral surface 3A of the rotary drum 3, and the scraper 1
4 is attached to the outer wall of the sludge storage tank 10. The tip end of the scraper 14 scrapes off the sludge A applied and heated and dried on the outer peripheral surface 3A of the rotating drum 3 while bending in the rotating direction of the rotating drum 3. Below the rotary drum 3, a hopper 9 a, whose opening area is gradually reduced in a tapered shape on the opposite side (left side), is provided adjacent to the sludge storage tank 10, and a discharge port 9 of the sludge A is provided at a lower end of the hopper 9 a. Is open.

As shown in FIG. 1, a through hole 18a is formed in the center of the heat insulating material 18 from the side wall 2b so that the tip of the burner 30 faces the combustion chamber 3B in the rotary drum 3. It is attached to the side wall 2b. In this example, a gas regenerative burner is used for the burner 30.
This gas regenerative burner is a disk rotary burner manufactured by Terra Corporation under the trade name "TERRA RAC RC-1000", and can use dry exhaust gas discharged from the exhaust port 26 as combustion air. For this reason, a deodorizing device for the dried exhaust gas is not required, and the high-temperature dried exhaust gas is used, so that the combustion efficiency is extremely good. FIG. 6 shows a gas regenerative burner 30, which comprises a burner gun 31, a main body 32, a honeycomb casing 33, and a supply / exhaust nozzle 34 as shown in FIG.

With respect to the drying apparatus 1 according to the embodiment of the present invention having the above-described configuration, a drying mode of the liquid sludge A will be described.

For example, when producing fermented compost using livestock manure (raw sludge having a water content of about 95%), livestock manure is directly introduced into the drying apparatus 1 from the sludge inlet 21 into the sludge storage tank 10. throw into. After drying the livestock manure to a water content of about 50 to 60% suitable for the fermentation conditions by the drying apparatus 1 and then performing fermentation decomposition in a fermentation treatment facility, a high-quality organic compost can be produced.

In such a compost production process, livestock manure (liquid sludge) continuously introduced from the sludge inlet 21.
A is primarily stored in the sludge storage tank 10. At this time, the introduced sludge A is heated to 60 to 80 ° C. by the heat exchanger 11 and is preheated. The preheated sludge A is fed to the sludge header 12 by the feed pump 27. The sludge header 12 is provided on the outer peripheral surface 3 of the rotating drum 3.
A and is arranged in parallel with the rotating shaft 5 on the rotating drum 3.
A gutter-like space is formed by the outer peripheral surface 3A of the rotary drum 3 and the overflow line 12b, and the sludge A flowing into this space is distributed uniformly from the central portion to the left and right in the gutter-like space from the outer peripheral surface 3A side of the rotary drum 3. The water flows out parallel to the outer peripheral surface 3A of the rotating drum 3 while maintaining a constant water surface. That is, the guide wall 12 overflows toward the outer peripheral surface 3 </ b> A of the rotary drum 3.
The sludge A flowing out along a is guided by a groove formed between the outer peripheral wall 3A of the rotary drum 3 and the pressing roller 13 provided at the lower part of the sludge header 12, and rotates upward with respect to this groove. As shown in FIG. 2, the pressing roller 13 is rotated in a counterclockwise direction while being applied in a thin film shape having a substantially constant thickness by a holding roller 13 rotating clockwise as shown in FIG. . During this time, the sludge A is applied onto the outer peripheral surface 3A of the rotating drum 3 by the pressing roller 13, and the water content of the sludge A is reduced while the sludge A is rotated about 3/4 (rotation angle is about 270 °) to the position of the scraper 14. The rotation speed of the electric motor 5 is controlled and the time required for drying is set so that the water is dried at 50 to 60%, in other words, about 30 to 40%. During this time, the inside of the combustion chamber 3 </ b> B of the rotating drum 3 is heated to approximately 850 to 900 ° C. by the flame of the gas injected from the gas regenerative burner 30. At this time,
The temperature in the combustion chamber 3B is electrically measured via a temperature sensor (not shown), and the temperature data is fed back to control the combustion state of the gas regenerative burner 30. The heat of the heated air (heating atmosphere) in the combustion chamber 3B is transmitted to the outer peripheral wall 3A of the rotating drum 3,
The sludge A is indirectly heated by this heat, and the water content of the sludge A is gradually evaporated and dried.

While the sludge A is heated and dried, water vapor is generated and at the same time an intense odor is generated. These malodorous gases (odors) are discharged to the outside from the exhaust port 26 of the outer casing 2 and then become malodorous. The gas is directly guided to the combustion air supply port 30a of the gas regenerative burner 30 through the pipe 29 and the mist separator 35 provided in the middle by the air supply blower 36 provided in the middle of the pipe 29, and is used for combustion. It is used as air and is reburned without going out of the system of the drying device 1. The water separated by the mist separator 35 falls into the lower seal pot 37 and is collected. The offensive odor gas is burned at about 850 to 900 ° C. in the closed combustion chamber 3 </ b> B in the rotary drum 3 and decomposed, thereby completely eliminating the odor and rendering it odorless and harmless. Further, odorless and harmless exhaust gas generated by the reburning is discharged from the exhaust port 30b of the combustion chamber 3B,
8, is sent from the introduction pipe 22 to the heat exchanger 11,
Used for preheating sludge A. After the waste heat of the exhaust gas is effectively used for preheating the sludge A in this manner, the waste heat is discharged from the discharge pipe 23 to the atmosphere. Since the dried exhaust gas discharged from the exhaust port 26 of the outer casing 2 has a high temperature, the combustion efficiency is good.

The sludge A is applied thinly on the outer peripheral surface 3A of the rotary drum 3, and the gas regenerative burner 3
0 causes indirect heating from the inside of the rotating drum 3,
Drying is performed uniformly and efficiently in a short time (for example, about 10 minutes) with almost no generation of dust and the like. When the dried sludge A rotates and moves to the position of the scraper 14 in this manner, the tip of the scraper 14 is applied to the outer peripheral surface of the rotary drum 3 while being bent in the rotation direction of the rotary drum 3 and dried. To remove the sludge A that has adhered. The sludge A scraped off in this manner is once stored in the hopper 9a, and is discharged from the discharge port 9 at the lower end of the hopper 9a.
Dropped from and collected.

Although the embodiment of the drying apparatus of the present invention has been described above, the present invention can be implemented as follows.

In place of the gas regenerative burner 30, a general combustion device such as a gas burner or a petroleum burner can be used. However, the burner uses a burner that automatically controls proportionally the fuel supply amount and the combustion air amount, can adjust the combustion amount in the combustion chamber, maintains a constant high-temperature atmosphere, and has high thermal efficiency. Is desirable. Further, superheated steam can be introduced into the rotary drum 3 for heating. However, in this case, a facility for treating exhaust gas discharged from the exhaust port 26 to the outside may be required.

Needless to say, it can be used for drying muddy liquids other than sludge A.

The outer peripheral wall 3 A of the rotating drum 3 can be replaced with a heat-resistant metal plate having a different thickness according to the properties of the liquid material to be dried, and the amount of heat transferred (heat amount) can be adjusted. At the same time, the thickness and the material of the heat insulating material 18 and the heat insulating material 19 can be changed. Further, the heat insulating material 18
Instead of forming the heat insulating material 19 in a disk shape or a disk shape in advance and disposing the heat insulating material on both sides of the rotating drum 3, for example, covering the opening with a metal plate and spraying a heat insulating material on the surface thereof, or forming a mortar inside the opening. There are various cases such as forming by applying a heat insulating material.

In the above embodiment, the liquid sludge A having a water content of about 95% was dried to a water content of 50 to 60%. However, it is also possible to dry the liquid sludge A to, for example, about 10%. The drying time may be adjusted by, for example, reducing the rotation speed of the electric motor 6.

[0045]

As is apparent from the above description,
The drying device according to the present invention has the following excellent effects.

(1) According to the first aspect of the present invention, even liquid sludge such as livestock manure having a very high moisture content that cannot be directly dried by the drying apparatus described in the above-mentioned publication without any treatment is directly injected. Can be dried. In other words, the liquid sludge is preheated to reduce the water content to some extent, and is continuously applied in a thin film on the outer peripheral wall of the rotating drum, so that the contact area ratio of the liquid sludge to the heat medium can be increased. As well as minimizing the dissipation of heat to the outside, the heat energy of the heat medium is converted to the evaporation energy of the water contained in the sludge with high efficiency, and the sludge-like liquid material such as sludge is removed in a short time. And can be dried uniformly and efficiently. In addition, the structure of the entire apparatus is simple, and maintenance is easy.

(2) According to the second aspect of the invention, the water content is 9
When drying livestock manure or raw sludge containing a large amount of water of 0% or more, without performing any pretreatment such as dehydration treatment,
It can be applied continuously and thinly on the outer peripheral surface of the rotating drum, and can be dried efficiently in a short time.

(3) According to the third aspect of the present invention, odorless and harmless exhaust gas can be burned at a high temperature without separately providing a deodorizing device.

(4) According to the invention described in claim 4, when preheating a material to be dried such as livestock manure having a very high water content, a part of the heat required for heating and drying can be effectively used by utilizing waste heat. For example, frozen livestock manure in a cold region or the like can be dried without using a special thawing device, and the drying efficiency can be improved.

(5) According to the fifth aspect of the present invention, it is possible to supply, as combustion air, odorous gas or the like generated at the time of drying the material to be dried to the combustion chamber, and it is not necessary to separately provide a dedicated combustion chamber. The structure of the entire device is simplified.

(6) According to the sixth aspect of the invention, by controlling the amount of combustion in the combustion chamber proportionally, it is possible to easily adjust the water content of the material to be dried and the processing amount.

[Brief description of the drawings]

FIG. 1 is a central vertical cross-sectional view as viewed from the front showing an embodiment of a drying apparatus for liquid sludge according to the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a sectional view taken along line BB of FIG. 1;

FIG. 4 is a left side view of the sludge drying apparatus of FIG. 1;

FIG. 5 is a front view showing a liquid sludge A applying means and a preheating means in detail.

FIG. 6 is a perspective view showing a main configuration diagram of the gas regenerative burner 30.

[Description of Signs] 1 Drying device 2 Outer casing 3 Rotating drum 3A Outer peripheral wall 3B Combustion chamber 5 Rotating shaft 6 Electric motor 7 Drum retainer 10 Sludge storage tank 11 Heat exchanger (heating means) 12 Sludge header 13 Press roller 14 Scraper ( 17 Chain 18 Insulation material 19 Insulation material 20 Packing 30 Gas regenerative burner (combustion device) 35 Mist separator

Claims (6)

[Claims] 1. A rotating drum having a cylindrical metal outer peripheral wall in an outer casing is rotatably disposed about a horizontal axis, and the rotating drum is configured to be rotatable by a driving device. The inside of the drum is formed in a combustion chamber, the combustion chamber is configured to be able to heat the outer peripheral wall of the rotary drum via a combustion device, and the outer casing is provided with a heating means for preheating an object to be dried such as sludge. A sludge storage tank is provided, and coating means for continuously applying a preheated material to be dried into the sludge storage tank on the outer peripheral wall of the rotary drum is provided. A scraping means is provided, and the preheated object to be continuously applied on the outer peripheral wall of the rotary drum is indirectly heated and dried by conduction heat from a combustion chamber. Drying equipment for liquid sludge. 2. A press roller for thinning and applying a material to be dried, and a gutter for supplying a constant amount of the material to be dried near a contact position between the pressing roller and the outer peripheral wall of the rotating drum. The drying apparatus for liquid sludge or the like according to claim 1, comprising a dried object header. 3. An exhaust gas with an odor generated when preheating a material to be dried in the outer casing is introduced into a combustion chamber in the rotary drum, and is reburned by the combustion device for the combustion chamber. The drying device for deodorizing liquid sludge according to claim 1 or 2. 4. The heating means for preheating the material to be dried introduces exhaust gas discharged from the outer casing into a combustion chamber in the rotary drum, and reburns the exhaust gas by the combustion device for the combustion chamber. The drying device for liquid sludge or the like according to any one of claims 1 to 3, which is a heat exchanger using the exhaust gas. 5. A reburning furnace in which a combustion chamber in the rotary drum is deodorized by burning after removing water by a mist separator from exhaust gas containing water vapor and odor generated when drying an object to be dried. A drying device for the liquid sludge according to any one of claims 1 to 4, which is used as a device. 6. A burner which is capable of automatically controlling the amount of fuel supplied and the amount of combustion air in the combustion device to adjust the amount of combustion in the combustion chamber, maintaining a constant high-temperature atmosphere, and having high thermal efficiency. An apparatus for drying liquid sludge according to any one of claims 1 to 5, wherein the apparatus comprises: