JPH11300398A - Sludge treating device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the adverse effect of a flocculant on the drying performance of a centrifugal thin-film drier by decreasing the the amt. of the flocculant to be injected into the sludge supplied to the drier. SOLUTION: This sludge treating device is provided with a centrifugal thin- film drier 22 for drying the sludge charged therein and a centrifugal dehydrator 21 for dehydrating the sludge and supplying it to the drier 22. The sludge from the dehydrator 21 is supplied into a mixer 40, and the soil having a low content of water and supplied from a soil feeder 41 is charged into the mixer 40. The sludge and soil are mixed in the mixer 40, and the sludge charged with the soil is then sent to the drier 22.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to, for example, sewage treatment,
The present invention relates to a sludge treatment device used for industrial wastewater treatment, nuclear waste liquid treatment, and the like.

[0002]

2. Description of the Related Art A conventional sludge treatment apparatus will be described with reference to FIG. This sludge treatment apparatus includes a centrifugal thin film dryer 22 having a heat transfer drum, and a centrifugal dehydrator 21 for dewatering sludge and sending the sludge to the centrifugal thin film dryer 22.

The sludge is pumped from a sludge storage tank 20 by a pump 27.
The coagulant sent from the coagulant tank 25 by the pump 28 is injected into the sludge, and thereafter the sludge is dewatered in the centrifugal dewatering machine 21 within a range where the fluidity is maintained.

[0004] The sludge dewatered by the centrifugal dehydrator 21 is
After being supplied to the centrifugal thin film dryer 22 by the pump 29, the sludge is dried and collected in the collecting can 30.

[0005] The steam generated from the sludge inside the centrifugal thin film dryer 22 is extracted, and the scrubber 26 and the deodorizer 2 are removed.
4 and sequentially released to the atmosphere below environmental standards. A shower nozzle is provided on the upper part of the scrubber 26, and a part of the steam of the sludge is aggregated by the discharge water 31 injected from the nozzle. The effluent water 31 that has reacted with the sludge steam in the scrubber 26 is returned to the sewage treatment plant. In this case, the deodorizing device 24 is filled with a catalyst, and the odor component of the steam generated from the sludge is decomposed into water and carbon dioxide.

[0006]

In such a sludge treatment apparatus, if the coagulant injected into the sludge supplied to the centrifugal dehydrator 21 is added to the sludge in an amount more than necessary,
This adversely affects the drying performance of the centrifugal thin film dryer 22. Further, in the centrifugal dehydrator 21, since the potash component contained in the sludge flows out to the side of the desorbing liquid, the balance of the fertilizer component is insufficient from the viewpoint of the reduction of the dried sludge to green farmland.

[0007] The present invention has been made in view of such a point, it is possible to reduce the amount of coagulant injected into the sludge, thereby improving the drying performance of the centrifugal thin film dryer. It is an object of the present invention to provide a sludge treatment device that can perform the treatment.

[0008]

SUMMARY OF THE INVENTION The present invention provides a centrifugal thin-film dryer having a heat transfer drum for drying sludge introduced therein, and a sludge supplied to the heat transfer drum of the centrifugal thin-film dryer. And a soil mixing apparatus for charging and mixing soil having a water content lower than that of the above, and a centrifugal thin film having a heat transfer drum for drying the sludge charged therein. A dryer, and a potash component material mixing device for charging and mixing a potash component material having a moisture content lower than the moisture content of the sludge with respect to the sludge supplied to the heat transfer drum of the centrifugal thin film dryer. It is a sludge treatment apparatus characterized by the above.

According to the present invention, the water content of the sludge supplied to the centrifugal thin film dryer can be reduced by charging the sludge with the soil or potash component material. The amount of the coagulant can be suppressed to a small amount. When a potash component material is added to the sludge, the potash component can be contained in the sludge dried by the centrifugal thin film dryer.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of a sludge treatment apparatus according to the present invention will be described with reference to the drawings. As shown in FIGS. 1 to 3, the sludge treatment device includes a centrifugal thin film dryer 22 having a heat transfer drum 1 (FIG. 2) for drying sludge introduced therein, and sludge supplied to the centrifugal thin film dryer 22. And a centrifugal dewatering machine 21 for dewatering in advance.

A centrifugal dehydrator 21 and a centrifugal thin film dryer 22
A mixing apparatus 40 is provided between the centrifugal dewatering machine 21 and the centrifugal dewatering machine 21 for supplying sludge supplied by the pump 29 with soil having a moisture content lower than that of the sludge. The mixing device 40 has a stirrer 42 inside, and the sludge and the soil are mixed by the stirrer 42. The sludge into which the soil has been introduced is then sent to the centrifugal thin film dryer 22 by the pump 43.

Further, sludge is supplied to the centrifugal dehydrator 21 from the sludge storage tank 20 by a pump 27.
The coagulant supplied from the coagulant tank 25 by the pump 28 is injected.

Heating steam is supplied from the boiler 23 to the centrifugal thin film dryer 22 to heat the outer surface of the heat transfer drum 1. Further, the steam generated from the sludge in the centrifugal thin film dryer 22 is guided to the scrubber 26 and the deodorizing device 24 and discharged to the atmosphere. Also scrubber 2
Discharge water is supplied to 6.

Next, the centrifugal thin film dryer will be described in detail with reference to FIGS.

FIG. 2A is an overall sectional view of a centrifugal thin film dryer, FIG. 2B is an enlarged view of a part b of FIG. 2A,
2C is an enlarged view of a portion c in FIG. 2A, and FIG. 2D is a partial enlarged view of a portion d in FIG. 2A. FIG. 3 is FIG.
It is sectional drawing which follows the EE line of (A).

As shown in FIGS. 2 and 3, the centrifugal thin film dryer 22 has a thin heat transfer cylinder 1 and a main shaft 2 provided coaxially with the heat transfer cylinder 1 in the heat transfer cylinder 1. ing. The main shaft 2 is rotationally driven by a drive motor 3 and a V-belt 3a.

Further, a distribution ring 5 is provided above the main shaft 2, and the sludge supplied from the sludge inlet 4 is uniformly supplied to the inner surface of the heat transfer cylinder 1 through the distribution ring 5. Further, in order to make the sludge dispersed in the heat transfer drum 1 into a thin film, a plurality of blades 6 are attached to the main shaft 2 in the axial direction and the circumferential direction. Since the blade 6 moves while maintaining a slight gap through the sludge between the blade 6 and the heat transfer drum 1, a large solid content may be entrapped. In order to prevent abnormalities caused by this biting, etc., the blade 6
A hinge 7 is attached to the base, and is movable to escape.

The main shaft 2 is supported at both ends of the heat transfer drum 1 by bearings 8 and 9, and the lower bearing 9 is held by the heat transfer drum 1 via spokes 10. An outlet 11 is formed below the spoke 10. Further, an exhaust port 12 for exhausting the evaporated vapor generated from the sludge and sending it to the scrubber 26 is provided at an upper portion of the heat transfer drum 1. Further, a steam jacket 13 through which steam serving as a heat source for performing dehydration and drying of sludge is provided outside the heat transfer drum 1, and steam sent from the boiler 23 is pressurized in the steam jacket 13. While flowing in from the steam inlet 14, the steam in the steam jacket 13 flows out from the pressurized steam outlet 15.

Next, the operation of the present embodiment having the above configuration will be described.

Sludge is pumped from sludge storage tank 20 by pump 27.
The coagulant sent from the coagulant tank 25 by the pump 28 is injected into the sludge, and thereafter the sludge is dewatered in the centrifugal dewatering machine 21 to the extent that the fluidity is maintained.

The sludge from the centrifugal dehydrator 21 is supplied to a pump 29
To the mixing device 40, and in the mixing device 40, the soil having a water content lower than the water content of the sludge (for example, the water content is less than 80%) is supplied to the sludge.
Thereafter, in the mixing device 40, the sludge and the soil are stirred by the stirrer 42.

Next, the sludge containing the soil is sent from the mixing device 40 to the centrifugal thin film dryer 22 by the pump 43 and dried.

That is, as shown in FIG. 2, the sludge 16 supplied into the heat transfer drum 1 from the sludge inlet 4 of the centrifugal thin film dryer 1.
Are distributed along the inner surface of the heat transfer drum 1 by the distribution ring 5 rotating together with the main shaft 2. Further, the sludge 16 is scraped off by the blade 6 rotating together with the main shaft 2, and is spread in a thin film on the inner surface of the heat transfer drum 1. And
The sludge 16 in the form of a thin film gradually moves downward due to gravity and the pressure of new sludge supplied one after another. that time,
The sludge 16 is heated by the heat transfer cylinder 1 by the heating steam supplied to the steam jacket 13 outside the heat transfer cylinder 1. Thereafter, the sludge 16 is gradually dehydrated to become dry sludge 17, and is discharged from the discharge port 11 provided at the lower end of the heat transfer drum 1. On the other hand, the vapor evaporated from the sludge 16 is extracted from the exhaust port 12 and exhausted.

As described above, the steam generated from the sludge inside the centrifugal thin film dryer 22 is bled, sequentially sent to the scrubber 26 and the deodorizer 24, and released to the atmosphere below environmental standards. A shower nozzle is provided on the upper part of the scrubber 26, and a part of the steam of the sludge is aggregated by the discharge water 31 injected from the nozzle. The effluent water 31 that has reacted with the sludge steam in the scrubber 26 is returned to the sewage treatment plant. In this case, the deodorizing device 24 is filled with a catalyst, and the odor component of the steam generated from the sludge is decomposed into water and carbon dioxide.

As described above, according to the present embodiment, the water content of the sludge can be reduced by adding the soil having a low water content to the sludge supplied from the centrifugal dehydrator 21. For this reason, in the centrifugal dehydrator 21, there is no need to excessively reduce the water content of the sludge.
In 1, the amount of the coagulant used can be reduced. By suppressing the use amount of the flocculant in this way, the drying performance of the centrifugal thin film dryer 22 is not adversely affected.

In the above embodiment, an example in which the centrifugal dehydrator 21 is provided has been described. However, if the water content of the sludge can be greatly reduced by the soil, the centrifugal dehydrator 21 is not necessarily provided. . Further, it is preferable to use soil collected from an area where the dry sludge 17 is applied.

Also, an example has been described in which the soil is supplied from the soil supply device 41 to the mixing device 40 and the soil is injected into the sludge. May be supplied to the mixing device 40, and the potash component material may be supplied to the sludge. When the potash component material is added to the sludge, the potash component that has become slightly insufficient due to the treatment in the centrifugal dehydrator 21 can be supplemented. In this case, the dried sludge 17 dried by the centrifugal thin film dryer 22 has a very good balance of the fertilizing effect component as compared with the conventional one, so that the effective green farmland can be reduced.

[0028]

As described above, according to the present invention, the drying performance in the centrifugal thin film dryer is deteriorated by reducing the amount of coagulant fed to the sludge supplied to the centrifugal thin film dryer. Never. Further, when a potash component is contained in the sludge, the balance of the fertilizer component of the dried sludge can be kept at an appropriate level.

[Brief description of the drawings]

FIG. 1 is a schematic view showing an embodiment of a sludge treatment apparatus according to the present invention.

FIG. 2 is a structural sectional view showing a configuration of a centrifugal thin film dryer.

FIG. 3 is a sectional view taken along line EE in FIG. 2;

FIG. 4 is a schematic diagram showing a conventional sludge treatment device.

[Description of Signs] 1 Heat transfer cylinder 16 Sludge 17 Dry sludge 20 Sludge storage tank 21 Centrifugal dehydrator 22 Centrifugal thin film dryer 23 Boiler 24 Deodorizer 25 Coagulant tank 26 Scrubber 40 Mixing device 41 Soil supply device 42 Stirrer

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI F26B 3/04 F26B 3/04 5/08 5/08 17/18 17/18 25/00 25/00 F G21F 9/08 521 G21F 9/08 521G 531 531A // (C05F 15/00 7:00 C05D 1:00) C09K 101: 00 (72) Inventor Koji Hayashi 1 Toshiba-cho, Fuchu-shi, Tokyo Toshiba Corporation Fuchu Plant

Claims (2)

[Claims] 1. A centrifugal thin film dryer having a heat transfer drum for drying sludge introduced therein, and a water content lower than the sludge water content of the sludge supplied to the heat transfer drum of the centrifugal thin film dryer. And a soil mixing device for charging and mixing the soil. 2. A centrifugal thin film dryer having a heat transfer drum for drying sludge introduced into the inside thereof, and a sludge supplied to the heat transfer drum of the centrifugal thin film dryer having a water content lower than that of the sludge. And a potash component mixing device for feeding and mixing the potash component material.