JP2002273497A - Sludge drying method and equipment for the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sludge drying equipment with which a treatment cost is made extremely low and stable drying efficiency is obtainable. SOLUTION: Various kinds of electric facilities driven in the sewage treatment by a sewage treatment equipment 2 for aerating sewage with air and decomposing organic matter by aerobic microorganisms are disposed in a machine room 5. A chain conveyor provided with a plurality of conveyance containers having filter sections on their base surfaces is disposed within a main body case. An exhaust duct 35 connected to an exhauster 6 of the machine room 5 is connected to the main body case. The excess sludge generated in the sewage treatment equipment 2 is fed into the conveyance containers where the moisture of the excess sludge is filtered and separated. The conveyance containers are conveyed and while the sludge is condensed by its own weight, the sludge is dried by the remaining heat from the electric facilities of the machine room 5 and the heated up exhaust air. The sludge is inexpensively, efficiently and stably dried by effectively utilizing the remaining heat of the electric facilities.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sludge drying method and apparatus for drying sludge generated by sewage treatment.

[0002]

2. Description of the Related Art Conventionally, there is known a sewage treatment method in which air, which is a gas containing oxygen, is aerated to sewage and organic matter in the sewage is decomposed by aerobic microorganisms. The excess sludge generated by this sewage treatment is concentrated and reduced in volume, for example, by gravity sedimentation, or reduced in volume by a dehydrator to a water content of about 80%.

[0003] By the way, surplus sludge generated by sewage treatment is about several liters per day per person to be treated, and is rapidly reduced in volume by concentration and dehydration. For this reason, the amount of sludge reduced in volume generated from sewage treatment is extremely small compared to the amount of treated sewage. Therefore,
The sludge whose volume has been reduced is carried out by, for example, a vacuum pumping vehicle or carried out by a container or the like, and collected and treated at a place different from the sewage treatment facility. That is, they are treated in a drying and incineration facility, or placed on a sand bed and dried in a solar drying facility, and then treated with soil improvement material, fertilizer, and the like.

[0004] However, in the method of incineration in a drying and incineration facility, sludge cannot be reused and the treatment cost becomes enormous. In addition, in the method of performing the sun drying treatment on the sand bed, the treatment cost depends on the weather because the drying efficiency of the sludge cannot be obtained, and a stable drying efficiency cannot be obtained, and a huge site is required.

Therefore, as a sludge drying apparatus for improving the drying efficiency without increasing the processing cost, Japanese Patent Laid-Open Publication No.
A configuration described in Japanese Patent No. 308698 is known.

In the sludge drying apparatus described in Japanese Patent Application Laid-Open No. Hei 7-308686, a net conveyor is provided in a transparent main body whose ceiling can be opened and closed. In addition, in the body,
It is located above the upstream side in the circulating direction of the net conveyor,
There is provided a molding device for forming sludge into flat pellets and dropping the sludge on a net conveyor. The sludge in the form of pellets is dried in the sun while being conveyed and moved at a low speed on a net conveyor.

[0007]

However, in the sludge drying apparatus described in Japanese Patent Application Laid-Open No. Hei 7-308686, the drying efficiency of sludge depends on the weather because it is dried in the sun, so that the drying efficiency is further improved. desired.

Further, various machines which are electric facilities for sewage treatment, such as a pump for conveying sewage and sludge and a blower for aeration, generate a certain amount of noise when driven during sewage treatment. For this reason, they are collectively installed in a machine room having a soundproof function. Various machines emit a certain amount of heat when driven. Therefore, in order to prevent an increase in the room temperature of the machine room, an exhaust device such as a ventilation fan is normally operated for 24 hours to perform ventilation.

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and provides a sludge drying method and an apparatus therefor that use heat generated by sewage treatment to obtain stable drying efficiency with extremely low treatment cost. With the goal.

[0010]

According to a first aspect of the present invention, there is provided a sludge drying method for drying sludge generated from a sewage treatment apparatus for decomposing organic substances contained in sewage by microorganisms. The residual heat from the electric facility of the processing apparatus is recovered, and the sludge is dried by the recovered residual heat.

Then, heat generated from electric facilities of the sewage treatment apparatus, for example, a motor of an aeration blower for aerating sewage with air, that is, residual heat is recovered, and sludge generated from the sewage processing apparatus is dried by the recovered residual heat. As a result, there is no need to separately provide a dedicated heat source for drying to condense and reduce the volume of sludge, and the configuration is simplified, the processing cost is reduced, and a relatively stable sewage treatment apparatus is used for stable treatment of sewage. The sludge is dried stably by the residual heat from the electric facility, and the drying efficiency is improved.

The sludge drying method according to the second aspect is the first aspect of the invention.
In the sludge drying method described above, the residual heat of the electric facility is collected by collecting the air that has exchanged heat with the electric facility, and the collected air is contacted with the sludge to be dried.

[0013] The air that has exchanged heat with an electric facility, for example, an electric motor of an aeration blower, is brought into contact with sludge and dried. Thus, the residual heat is easily recovered from the electric facility, and the sludge is efficiently and stably dried.

According to a third aspect of the present invention, there is provided a method for drying sludge.
In the sludge drying method described above, the air brought into contact with the sludge is used as a gas to be aerated in the sewage treatment apparatus.

[0015] The air contacted with the sludge is used as the gas to be aerated in the sewage treatment apparatus. Thus, for example, in the deodorizing process of the gas aerated by the sewage treatment device, the air having an unpleasant odor due to the contact with the sludge is deodorized, and there is no need to separately perform the deodorizing process on the air that has come into contact with the sludge. Become Furthermore, the waste heat from the electric facility of the air increases the temperature of the sewage when the organic matter is decomposed by the microorganisms, for example, thereby increasing the activity of the microorganisms, thereby improving the sewage treatment efficiency.

The sludge drying method according to the fourth aspect is the first aspect of the invention.
In the sludge drying method according to any one of the above-described items 3, sludge is put on a water-permeable filter, and is dried by residual heat of an electric facility while filtering and separating water.

Then, the sludge is put on a permeable filter, and is dried by the residual heat of the electric facility while filtering and separating water. Thereby, the drying property of the sludge is improved with a simple configuration.

According to a fifth aspect of the present invention, there is provided a sludge drying apparatus comprising: a recovery means for recovering residual heat from an electric facility of a sewage treatment apparatus for decomposing organic substances contained in sewage by microorganisms; and a residual heat recovered by the recovery means. Drying means for drying the sludge generated from the sewage treatment apparatus.

Then, heat generated from an electric facility of the sewage treatment apparatus, for example, an electric motor of an aeration blower for aerating air to sewage, that is, residual heat is recovered by a recovery means, and sludge generated from the sewage processing apparatus by the recovered residual heat. Is dried by a drying means. As a result, there is no need to separately provide a dedicated heat source for drying to concentrate and reduce the volume of sludge, and the configuration is simplified, the treatment cost is reduced, and the wastewater is generated relatively stably for stable treatment of the wastewater. The sludge is dried stably by the residual heat from the electric facility of the sewage treatment apparatus, and the drying efficiency is improved.

[0020] The sludge drying apparatus according to the sixth aspect is the fifth aspect of the present invention.
The sludge drying apparatus according to the above aspect, wherein the recovery unit includes a duct that recovers the air that has exchanged heat with the electric facility and blows the recovered air to the drying unit, and the drying unit converts the air blown from the recovery unit into sludge. To dry the sludge.

Then, the air which has exchanged heat with an electric facility, for example, an electric motor of an aeration blower, is collected, sent to a drying means through a duct, and brought into contact with sludge to be dried. As a result, heat is easily recovered from the electric facility, and the sludge is efficiently and stably dried with the warmed air to be blown.

The sludge drying apparatus according to claim 7 is the same as the claim 6.
In the above described sludge drying apparatus, air obtained by drying the sludge is used as a gas to be aerated in the sewage treatment apparatus.

Then, the dried air is used as the gas to be aerated in the sewage treatment apparatus. Thus, for example, in the deodorizing process of the gas aerated by the sewage treatment device, the air having an unpleasant odor due to the contact with the sludge is deodorized, and there is no need to separately perform the deodorizing process on the air that has come into contact with the sludge. Become Furthermore, the waste heat from the electric facility of the air increases the temperature of the sewage when the organic matter is decomposed by the microorganisms, for example, thereby increasing the activity of the microorganisms, thereby improving the sewage treatment efficiency.

[0024]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, a configuration of an embodiment of a sewage treatment method of the present invention will be described with reference to the drawings.

In FIG. 1, reference numeral 1 denotes a sewage treatment facility for treating sewage containing organic substances. The sewage treatment facility 1 includes a sewage treatment apparatus 2 for purifying sewage. The sewage treatment apparatus 2 has a treatment tank (not shown) capable of storing sewage together with aerobic microorganisms. The sewage to be treated by the sewage treatment apparatus 2 includes, for example, sewage, rainwater, industrial wastewater, human wastewater, secondary treated water after sewage treatment, water from rivers and lakes, and tap water and groundwater. May be.
The treatment tank is connected to a raw water pipe (not shown) through which sewage flows. The processing tank is provided with aeration means (not shown) for aerating sewage that stores oxygen, for example, air, which is a gas containing oxygen. This aeration means
A diffuser tube is provided at the bottom of the processing tank to diffuse air, and a blower blows air through the diffuser tube.

Further, a water pipe provided with a pump (not shown) for discharging sewage treated with organic substances by microorganisms to the outside of the tank is connected to the treatment tank. The water pipe is provided with a solid-liquid separating means (not shown) for solid-liquid separation of the waste water into separated water and sludge. Further, the solid-liquid separation means is provided with a discharge pipe (not shown) for flowing the separated water out of the system as treated water. Further, the solid-liquid separation means is provided with a sludge return pipe provided with a pump (not shown) for returning a part of the separated sludge to the treatment tank.

The solid-liquid separating means is provided with an excess sludge discharge pipe 3 equipped with a pump (not shown) for discharging the remaining sludge as excess sludge. The excess sludge discharge pipe 3 is connected to a sludge concentration storage tank for storing excess sludge. This sludge thickening tank sediments and concentrates excess sludge to be stored. In addition, a sludge discharge pipe 7 for discharging surplus sludge settled and concentrated is connected to the sludge concentration tank.

The sewage treatment facility 1 includes a sewage treatment unit such as a blower and pumps for aeration means, a power supply unit (not shown) for supplying power to these blowers and pumps, and a control unit (not shown) for controlling driving of the blowers and pumps. A machine room 5 is provided as a collection unit 4 in which electric facilities, which are various machines for operating the facilities, are provided. The machine room 5 is partitioned from the outside so as to prevent noise generated by driving various electric facilities from leaking to the outside. Further, the machine room 5 is provided with an exhaust device 6 such as a ventilation fan that constitutes the recovery unit 4 in order to prevent the internal temperature from rising.

Further, a machine room 5 is provided in the sewage treatment facility 1.
Sludge drying device 10 is installed adjacent to. The sludge drying device 10 includes a main body case 11, as shown in FIGS. The main body case 11 includes a frame member 12
And a plate member (not shown) that closes a surface formed by the frame member 12, and is formed in a box shape. Inside the main body case 11, a sludge input chamber 13, a sludge drying chamber 14 which is continuous with the sludge input chamber 13 and dries sludge, and a dry sludge discharge which is continuous with the sludge drying chamber 14 and discharges dried sludge. A chamber 15 is formed.

In the main body case 11, a sludge charging chamber is provided.
13, a sludge drying chamber 14 and a dry sludge discharge chamber 15 are provided with a chain conveyor 18 as a transporting means around which a pair of endless chains 17 are stretched. The chain conveyor 18 includes a driving pulley 19 and a guide pulley 20, a pair of endless chains 17 that are wound around the driving pulley 19 and the guide pulley 20, and an illustration of rotating the driving pulley 19 to rotate the endless chain 17. And driving means such as an electric motor. And the chain conveyor 18
The endless chain 17 is wound around the sludge input chamber 13 in a substantially horizontal direction, is turned obliquely upward in the sludge drying chamber 14, and is installed in a state where the endless chain 17 is turned upside down in the dried sludge discharge chamber 15. ing.

The pair of endless chains 17 are provided with a plurality of pairs of support plates 22 at opposing positions. The shaft support plates 22 protrude outward with respect to the circulation of the endless chain 17, and a plurality of pairs are provided at predetermined intervals in the circulation direction of the endless chain 17.

A transport container 24 is provided on the pair of support plates 22. The transfer container 24 has a rectangular frame-shaped frame portion 25 having an open upper surface and a lower surface, and a filter, for example, a mesh-shaped filter portion 26 which is a filter attached by closing the lower surface of the frame portion 25. Is formed in an open box shape. Sludge can be put into the transfer container 24 from the upper surface, and the sludge that has been put in is filtered by the filter unit 26 so that only solid components are captured on the filter unit 26. In addition, the frame 25 of the transport container 24 has a rotating shaft 27 located on both sides on one end side.
Are protruded from each other. The rotating shafts 27 are rotatably supported by the shaft supporting plates 22, respectively, and the transport container 24 is rotatable around the rotating shaft 27 in the reciprocating direction of the endless chain 17. In addition, in the transport container 24,
A guide roller 28 is provided at an end opposite to the side supported by the rotating shaft 27, that is, at a position corresponding to the upstream side of the endless chain 17 in the circulating direction.

Further, the pair of endless chains 17 are provided with elongated rod-shaped mounting rods 29 whose longitudinal direction is along the facing direction in a state of being bridged. The number of the mounting rods 29 is provided at a position corresponding to the number of the transport containers 24 at a position separated from the rotary shaft 27 of the transport container 24 by a predetermined distance upstream of the endless chain 17 in the circulating direction. Further, the mounting rod 29 is provided so that the transport container 24 can be placed, that is, located on a rotation locus of the transport container 24 about the rotation shaft 27 as a rotation center, and regulates the rotation of the transport container 24. The chain conveyor 18 having the transfer container 24 and the sludge drying chamber 14 of the main body case 11 constitute a drying unit 30.

On the other hand, a sludge discharge pipe 7 connected to the sewage treatment apparatus 2 is connected to the upper part of the sludge input chamber 13 of the main body case 11. The sludge discharge pipe 7 is capable of introducing surplus sludge in a state where the transport container 24 of the chain conveyor 18 is located below. Further, a water collecting section 31 is provided in the main body case 11 from the sludge input chamber 13 to the sludge drying chamber 14. The water collecting portion 31 is provided below the transport container 24 having an upper surface opening upward, and is opened upward to collect water filtered by the filter portion 26 of the transport container 24. Water. Further, a return pipe 32 for returning the collected water to the treatment tank of the sewage treatment apparatus 2 as a desorbed liquid is connected to the bottom of the water collecting section 31.

In the upper part of the sludge drying chamber 14 of the main body case 11, exhaust gas which is heated by residual heat from an electric facility of the machine room 5, for example, an electric motor of a blower of aeration means and is exhausted by the exhaust device 6 is provided. Exhaust duct that blows wind, that is, hot air
35 is connected. The exhaust duct 35 allows the air heated in the machine room 5 to flow into the sludge drying room 14 as warm air. The exhaust duct 35, the machine room 5, and the exhaust device 6 constitute the recovery unit 4.

Further, the drying sludge discharge chamber 15 of the main body case 11
Is provided with a guide rail 37. The guide rail 37 is provided substantially along the trajectory of the endless chain 17, and when the endless chain 17 is turned so that the upper surface of the transfer container 24 is turned downward, the guide rollers 28 of the transfer container 24 are rotated. And the state where the upper surface of the transport container 24 faces downward is maintained. Further, the dry sludge discharge chamber 15 is provided with a sludge collection unit such as a container (not shown) that collects the sludge that falls when the upper surface of the transport container 24 is turned downward. The sludge recovery section is disposed so as to be able to be taken out of the dry sludge discharge chamber 15.

The main body case 11 is connected to an exhaust pipe 39 for discharging air that has flowed into the main body case 11 through an exhaust duct 35. This exhaust pipe 39 is used for the sewage treatment device 2
To supply air to be discharged to the suction side of the blower of the aeration means.

Next, the operation of sewage treatment by the sewage treatment facility of the above embodiment will be described.

First, sewage flows into a treatment tank of a sewage treatment apparatus 2 of a sewage treatment facility 1 via a raw water pipe. And
The sewage flowing into the treatment tank is aerated with air from the air diffuser by driving the blower of the aeration means. By the aeration from the aeration means, organic substances in the wastewater are oxidatively decomposed by aerobic microorganisms that have been acclimated in the treatment tank in advance. Then, the sewage stays in the treatment tank for a predetermined time, is treated by the aerobic microorganisms, and then flows into the solid-liquid separation means via the water pipe. The sewage flowing into the solid-liquid separation means is separated into separated water and sludge by solid-liquid separation. Then, the separated water separated is returned to the sewage treatment apparatus 2 via the convection pipe. Further, a part of the separated sludge is returned to the treatment tank via a sludge return pipe, and the remaining part is conveyed to the sludge drying device 10 via the excess sludge discharge pipe 3 as surplus sludge.

The surplus sludge conveyed to the sludge drying device 10 via the surplus sludge discharge pipe 3 is put into a transfer container 24 whose upper surface is opened upward in the sludge input chamber 13.
The excess sludge is preferably introduced in such an amount that the thickness of the excess sludge is 2 cm to 10 cm. Then, the excess sludge introduced into the transfer container 24 is immediately
The water is filtered. As a result of the filtration of the water, as shown in FIG. 7, the solid matter 40 remaining on the filter section 26 is concentrated and formed into a layered state condensed into a cake. Then, the filtered water is collected in a water collecting section 31 located below, returned to the treatment tank of the sewage treatment apparatus 2 via a return pipe 32, and reprocessed.

Further, the solid matter 40 remaining after the moisture is filtered in the transfer container 24 is transferred to the sludge drying chamber 14 by the endless chain 17 which is opened by driving of the driving means. Here, the transport container 24 that has been moved to the sludge drying chamber 14 is moved upward by the endless chain 17 that is disposed inclining in the sludge drying chamber 14. During this movement, the transport container 24 is supported by the shaft supporting plate 22 of the endless chain 17 on the rotating shaft 24 on the moving direction side, and is placed on the mounting rod 29 on the side opposite to the moving direction. For this reason, the transport container 24 is moved in an inclined state. When the transfer container 24 is tilted, the solids 40 from which the moisture has been filtered are condensed in a cake shape,
It does not slip down to the lower side, and retains a layered form on the filter section 26 as shown in FIG. For this reason, the thickness D of the solid content in the direction of gravity is
Is longer than the thickness L in the gravitational direction when positioned horizontally in the sewage input chamber 13 that does not tilt. Therefore, as the thickness in the direction of gravity increases and the consolidation effect increases, moisture is squeezed out, and the solid content is further filtered and condensed.

Further, a transport container that moves in the sludge drying chamber 14
The solid content in 24 is dried by the warm air from the machine room 5 flowing in through the exhaust duct 35 while condensing. The warm air in the main body case 11 blown from the exhaust duct 35 is blown to the aeration means 41 of the sewage treatment apparatus 2 through the exhaust pipe 39, and is used as air to be sucked and aerated from the blower of the aeration means. You.

Then, the transport container 24 containing the sludge dried in the sludge drying chamber 14 moves to the dry sludge discharge section 15.
When moving from the sludge drying chamber 14 to the dry sludge discharge section 15, the chain conveyor 18 is inverted, so that the transport container 24 is also inverted. That is, the opening upper surface is inverted to the state of opening downward. Due to this reversal, the free end side opposite to the side supported by the rotation shaft 27 rotates downward by its own weight. Then, the guide roller 28 is
Of the transport container
The inverted state of 24 is opened downward. Due to the reversal of the transport container 24, the dried sludge accommodated inside is
It falls downward and is collected by the sludge collection section. In addition,
Even if a part of the dried sludge adheres to the filter section 26, the guide roller 28 separates and falls due to an impact when the guide roller 28 runs on the guide rail 37. Then, the sludge collecting section that has collected the dried sludge is taken out of the main body case 11 as appropriate, and is reused as a soil improvement material, a fertilizer, a fuel, or the like.

As described above, in the above-described embodiment, the blowers and pumps of the aeration means used in sewage treatment, the power supply unit (not shown) for supplying power to these blowers and pumps, and the driving of the blowers and pumps are controlled. The excess sludge is dried by heat generated by driving the electric facility of the sewage treatment apparatus 2 such as a control unit (not shown). For this reason, there is no need to separately provide a dedicated heat source for drying and condensing and reducing the volume of sludge, so that the configuration can be simplified and the processing cost can be reduced. Furthermore, since the heat generated from the sewage treatment apparatus 2 is used relatively stably for the stable treatment of the sewage, the sludge can be dried more stably than in the case of solar drying, and the drying efficiency can be improved. Further, the treatment can be performed in the sewage treatment facility 1, and there is no need to transport the sludge treatment facility to another sludge treatment facility as in the related art, thereby facilitating the treatment. Further, it is not necessary to modify the conventional sewage treatment apparatus, and it is only necessary to blow the exhaust air exhausted from the machine room 5 which has been exhausted through the exhaust duct 35, and the existing sewage treatment apparatus can be easily applied. Can be installed.

Then, the heat generated from the electric facilities, which are various machines of the sewage treatment apparatus 2, is recovered by recovering the air in the machine room 5 which has exchanged heat with the heat, and the recovered air is brought into contact with the sludge as warm air. And dry. For this reason, the heat generated from the machine can be easily recovered, and since the hot air drying is performed directly, the sludge can be efficiently and stably dried, and the drying efficiency can be improved.

Further, in order to prevent noise, electric facilities which are various machines for sewage treatment of the sewage treatment apparatus 2 are provided in the machine room 5, so that the temperature in the machine room 5 is generated by driving the electric facilities. Rises with residual heat. For this reason, the air heated by the heat exchange by the residual heat from the electric facility is collected in the exhaust duct 35 without being exhausted by the exhaust device 6 as it is, and is used for drying. To prevent damage due to overheating of electrical facilities,
Sludge can be dried without the need to separately provide a dedicated heat source for drying.

Further, the air brought into contact with the sludge for drying the sludge is sent to the sewage treatment apparatus 2 through the exhaust pipe 39,
It is used for air to be aerated by the aeration means of the sewage treatment apparatus 2. For this reason, even if the air has an unpleasant odor due to contact with the sludge, the air is used as the air to be aerated from the aeration means of the sewage treatment apparatus 2 without being exhausted as it is. In addition, the size and weight of the sewage treatment facility 1 can be reduced, the constructability of the sewage treatment facility 1 can be improved, and the construction cost can be reduced. Furthermore, by using air in which the amount of heat remaining after being brought into contact with the sludge for aeration is used, for example, when decomposing organic substances by microorganisms, the temperature of the sewage increases, and the activity of the microorganisms increases. Can also be improved.

A sludge drying apparatus 10 for drying sludge
In addition, a chain conveyor 18 for conveying sludge is provided. Therefore, the sludge can be continuously dried, and the drying efficiency can be improved.

Then, a transport container 24 for storing sludge is provided on the chain conveyor 18, and the transport container 24 is configured to move around. Therefore, even sludge having a relatively large water content and fluidity can be easily transported and dried, and the drying property of the sludge can be improved.

A filter 26 having water permeability is provided at the bottom of the transport container 24. For this reason, the sludge introduced into the transfer container 24 is transferred and dried while the moisture is filtered and separated, so that the drying property of the sludge can be easily improved with a simple configuration.

Then, the transport container 24 is moved to the bottom filter section 26.
The sludge is conveyed while being moved in a state where the plane is inclined upward to intersect the horizontal direction. As a result, the thickness of the sludge in the gravitational direction becomes thicker, the sludge is efficiently condensed by its own weight, and the sludge is filtered and separated so that the water is squeezed out, further improving the drying property of the sludge. it can.

Further, the sludge is put into the transfer container 24 on the filter section 26 so as to have a thickness of 10 cm or less. Therefore, the heat of the warm air is transmitted to the entire sludge and the surface area per volume of the sludge increases, so that the drying property of the sludge can be easily improved.

The water collecting part 31 filtered in the transport container 24
From the sludge input chamber 13 to the sludge drying chamber 14,
An exhaust duct 35 is connected to the upper part of the 11 sludge drying chamber 14. For this reason, since the warm air from the exhaust duct 35 flows through a portion in which the transport container 24 is moved by the endless chain 17 in a duct shape formed by the plate member forming the main body case 11 and the water collecting portion 31. In addition, the hot air can efficiently act on the drying of the sludge, the drying efficiency can be improved, and the odor control is easy and the structure can be simplified.

In the above-described embodiment, the structure in which the chain conveyor 18 is provided and the sludge is dried almost continuously has been described. However, it is also possible to adopt a structure in which the inputted sludge is dried by the recovered heat without being transported. it can.

A box-shaped transport container 24 is attached to the endless chain 17.
Although the chain conveyor 18 provided with the sludge is provided and described, a configuration in which sludge is directly mounted on an endless belt and conveyed, for example, such as a belt conveyor, may be used. By using this endless belt-shaped transporting means, sludge can be continuously introduced and dried continuously, and the drying treatment efficiency can be improved.
In this case, the endless belt preferably has water permeability. That is, the drying property of the sludge can be improved by adding a configuration in which the water is immediately separated from the fed sludge by filtration and dewatering. Further, it is preferable to provide a scraping member such as a scraper for dropping the dried sludge from the endless belt, or to provide a configuration for dropping by applying vibration or impact.

Furthermore, although the sludge is continuously dried by providing the chain conveyor 18, the sludge is introduced into the transport container 24, a box-like member having no filter portion 26, on the filter portion 26, or the like. After drying, the transfer container 24 and the box-shaped member are taken out and discharged, or the filter section 26 is turned upside down, and the sludge is dried batchwise to cope with it.

The exhaust air exhausted to prevent the temperature inside the machine room 5 from rising is collected, and the collected exhaust air is dried by directly contacting the sludge. For example, the collected exhaust air is circulated. It is also possible to dispose a plurality of elongated tubular members at a position where sludge is conveyed, and to circulate through the tubular members and dry them by radiant heat.

Further, the electric facility of the wastewater treatment apparatus 2 is disposed in the machine room 5 and the air exchanged with the electric equipment in the machine room 5 is recovered and explained. For example, the largest output is generated. The heat may be recovered only from the electric motor of the blower for aeration, which has a large amount of heat and is always driven, and the sludge may be dried. In other words, the aeration means is constantly driven during the sewage treatment and has a large output and generates the most heat, so that a certain amount of heat can be recovered stably and the sludge can be dried stably. Moreover, since the amount of aeration and the amount of generated excess sludge increase in proportion to the increase in the amount of wastewater treatment, the amount of heat corresponding to sludge drying can be easily secured.

Then, the plate material of the main body case 11 may be formed of a translucent member and installed outdoors. According to this configuration,
Sun drying can be used together with drying by the exhaust air, and the drying efficiency of sludge can be further improved.

Although the transport container 24 into which the sludge has been introduced is transported in an inclined manner, it is also possible to simply transport the filter unit 26 in a posture in which the plane of the filter unit 26 extends along the horizontal direction.

Further, the exhaust duct 35 is provided in the main body case 11.
A guide plate or the like may be provided so that warm air from the air directly hits the sludge. According to this configuration, the drying efficiency of the sludge can be further improved.

The exhaust air, which is the warm air that is heated and exhausted by the drive of the electric motor during the sewage treatment, is used for drying the sludge. Use it for any other heat source, such as warming the wastewater stored in the tank to increase the activity of microorganisms, or using methane fermentation to heat organic waste such as garbage during methane fermentation in a processing facility I can do it.

Further, the exhaust air may be brought into contact with water to produce hot water, the electric motor may be water-cooled, heated cooling water may be used as a heat source, or it may be used directly for hot water showers or hot water pools. it can.

Further, a configuration has been described in which sewage is aerated with oxygen-containing gas to purify sewage by aerobic microorganisms. For example, a gas such as air is not aerated, or a small amount is aerated. Sludge generated when an organic substance is decomposed by an anaerobic microorganism or a gas-permeable microorganism can also be used.

Then, a sludge drying device is installed in the sewage treatment facility 1.
Although 10 is provided, it may be provided in the vicinity of the sewage treatment facility 1, for example, adjacent to the sewage treatment facility 1.

[0066]

According to the sludge drying method of the first aspect,
The waste heat from the electrical facility of the sewage treatment device is recovered, and the sludge from the sewage treatment device is dried by the recovered residual heat.Therefore, there is no need to separately provide a dedicated heat source for drying to concentrate and reduce the volume of the sludge. The structure can be simplified and the treatment cost can be reduced, and the sludge can be dried relatively stably by the residual heat from the electric facility of the sewage treatment apparatus for stable treatment of the sewage, and the drying efficiency can be improved.

According to the sludge drying method of the second aspect, in addition to the effect of the sludge drying method of the first aspect, the air that has been heat-exchanged with the electric facility is brought into contact with the sludge to be dried, so that the air can be easily discharged from the electric facility. Residual heat can be recovered, and sludge can be dried efficiently and stably with warmed sludge.

According to the sludge drying method of the third aspect, in addition to the effect of the sludge drying method of the second aspect, the air contacted with the sludge is used as the gas to be aerated by the sewage treatment apparatus. When the gas aerated by the apparatus is deodorized, the air having an unpleasant odor is deodorized by contact with the sludge, and the air contacted with the sludge does not need to be separately deodorized, and the configuration can be simplified. Further, the residual heat from the electric facility where the air remains can increase the temperature of the sewage and increase the activity of the microorganisms when, for example, decomposing organic substances by microorganisms, so that the sewage treatment efficiency can be improved.

According to the sludge drying method of the fourth aspect, in addition to the effect of the sludge drying method of any one of the first to third aspects, the sludge is put on a permeable filter to filter and separate water. Since the drying is performed by the residual heat of the electric facility, the drying property of the sludge can be improved with a simple configuration.

According to the sludge drying apparatus of the fifth aspect, the residual heat from the electric facility of the sewage treatment apparatus is recovered by the recovery means, and the sludge from the sewage processing apparatus is dried by the drying means by the recovered residual heat. Therefore, there is no need to separately provide a dedicated heat source for drying and condensing and reducing the volume of sludge, so that the configuration can be simplified and the processing cost can be reduced, and a relatively stable sewage treatment apparatus can be used for stable treatment of sewage. Sludge can be dried stably by the residual heat from the electric facility, and the drying efficiency can be improved.

According to the sludge drying apparatus of the sixth aspect, in addition to the effect of the sludge drying apparatus of the fifth aspect, the air exchanged with the electric facility is recovered and sent to the drying means through a duct to form the sludge. The wastewater can be easily recovered from the electric facility, and the sludge can be efficiently and stably dried with the warmed air to be blown.

According to the sludge drying apparatus of the seventh aspect, in addition to the effect of the sludge drying apparatus of the sixth aspect, the sludge drying air is used as the gas to be aerated in the sewage treatment apparatus. When the gas aerated by the apparatus is deodorized, the air having an unpleasant odor is deodorized by contact with the sludge, and the air contacted with the sludge does not need to be separately deodorized, and the configuration can be simplified. Further, the residual heat from the electric facility where the air remains can increase the temperature of the sewage and increase the activity of the microorganisms when, for example, decomposing organic substances by microorganisms, so that the efficiency of sewage treatment can be improved.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a sewage treatment facility according to an embodiment of the present invention.

FIG. 2 is a side sectional view of the same sludge drying apparatus.

FIG. 3 is a rear cross-sectional view showing the sludge drying device.

FIG. 4 is a side cross-sectional view illustrating a situation where the transport container of the sludge drying device is inverted.

FIG. 5 is a perspective view showing a state of the transport container in a state where sludge of the sludge drying device is put into the same;

FIG. 6 is a perspective view showing a state of the transport container in a state in which dried sludge is discharged from the sludge drying apparatus.

FIG. 7 is a cross-sectional view showing a state of sludge put into the transport container.

[Explanation of symbols]

 2 Sewage treatment equipment 4 Recovery means 10 Sludge drying equipment 26 Filter part which is a filter 30 Drying means 35 Exhaust duct which is a duct

Claims (7)

[Claims] 1. A sludge drying method for drying sludge generated from a sewage treatment apparatus for decomposing and treating organic substances contained in sewage with microorganisms, the method comprising recovering residual heat from an electric facility of the sewage treatment apparatus. A sludge drying method, characterized in that the sludge is dried by the generated residual heat. 2. The sludge drying method according to claim 1, wherein the residual heat of the electric facility is recovered by collecting air exchanged with the electric facility, and the collected air is dried by contacting the collected air with sludge. . 3. The method for drying sludge according to claim 2, wherein the air brought into contact with the sludge is used as a gas to be aerated in the sewage treatment apparatus. 4. The method for drying sludge according to claim 1, wherein the sludge is put on a permeable filter and dried by residual heat of an electric facility while filtering and separating water. 5. A recovery means for recovering residual heat from an electric facility of a sewage treatment apparatus for decomposing organic substances contained in sewage by microorganisms, and sludge generated from the sewage treatment apparatus by the residual heat recovered by the recovery means. A drying unit for drying the sludge. 6. The recovery means includes a duct for recovering air that has exchanged heat with the electric facility and blowing the recovered air to a drying means, and the drying means contacts the air blown from the recovery means with sludge. The sludge drying device according to claim 5, wherein the sludge is dried. 7. The sludge drying apparatus according to claim 6, wherein the air obtained by drying the sludge is used as a gas to be aerated in the sewage treatment apparatus.