JPH1123147A - Centrifugal film drier - Google Patents

Abstract

PROBLEM TO BE SOLVED: To dry highly viscous sludge with high efficiency. SOLUTION: This drier is provided with a main shaft 2 which has a blade 4, within a heat conductive drum, and the inside of the heat conductive drum is partitioned into a low temperature heating region 15 and a high-temperature heating region 16 from above to below. This is provided with a low-temperature heater 14 for a low-temperature heating region 15 and a high-temperature heater 5 for a high-temperature heating region 16 outside the heat-conductive drum. The sludge cast in through a sludge input port 1a is heated at a low temperature by the low-temperature heater 14, and the viscosity drops. Next, the sludge is drawn out within the low-temperature drum by a blade 4, and it is heated with the high-temperature heater 5 thereby being dried. The dried sludge 6 is discharged from a sludge exhaust port.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a centrifugal thin film dryer for drying sludge used in the food industry, chemical industry, industrial waste treatment industry, water treatment industry and the like.

[0002]

2. Description of the Related Art FIGS. 2 and 3 show the structure of a conventional centrifugal thin film dryer. 2 (a) is an overall side view of the centrifugal thin film dryer, FIG. 2 (b) is an enlarged view of a portion B in FIG. 2 (a),
2C is an enlarged view of a part C in FIG. 2A, and FIG. 2D is an enlarged view of a part D in FIG. 2A.

In FIGS. 2 and 3, a heat transfer cylinder 1 and a main shaft 2 of a body shaft are provided inside a thin heat transfer cylinder 1, and the main shaft 2 is driven and rotated by a motor 7. In addition, a distribution ring 3 for dispersing the sludge supplied into the heat transfer cylinder 1 from the sludge inlet 1a along the inner surface of the heat transfer cylinder 1 is provided at an upper portion of the main shaft 2, and further provided at another portion of the main shaft 2. A plurality of blades 4 are attached axially and circumferentially to form a thin film of sludge dispersed on the inner surface of the heat transfer drum 1 by the distribution ring 3. The blade 4 is a heat transfer cylinder 1
Since it moves while maintaining a small gap between the solid portion and the solid portion, entrapment of a large solid portion may occur. In order to prevent the above from being caused by the biting or the like, the blade 4 has a hinge-shaped base so that the blade 4 can escape.

A spoke 13 for rotatably supporting the main shaft 2 by a bearing 13a is provided at a lower end of the heat transfer drum 1, and a discharge port 1b is formed below the spoke 13. Further, an exhaust port 12 for exhausting evaporated vapor generated from sludge is provided at an upper portion of the heat transfer drum 1.

Further, on the outside of the heat transfer cylinder 1, dewatering of sludge is performed.
A steam shacket as a heat source for drying is provided, and steam enters the steam jacket 5 from a steam inlet 5a, and steam in the steam jacket 5 flows out from a steam outlet 5b.

The sludge 6 supplied into the heat transfer drum 1 from the sludge inlet 1a is distributed along the heat transfer drum 1 by a distribution ring 3 rotating together with the main shaft 2. Further sludge 6
Is scraped off by a blade 4 rotating together with the main shaft 2 and is stretched into a thin film on the inner surface of the heat transfer cylinder 1. And
The sludge 6 in the form of a thin film gradually moves downward due to gravity and the pressure of new sludge supplied one after another. At this time, the sludge 6 is heated in the heat transfer cylinder 1 by the heating steam supplied to the steam jacket 5 outside the heat transfer cylinder 1. Thereafter, the sludge 6 has its moisture evaporated and dried to become dried sludge, and the discharge port 1b provided at the lower end of the heat transfer drum 1
Is more exhausted. On the other hand, the vapor evaporated from the sludge is exhausted from the outlet 12.

[0007]

The sludge supplied to the centrifugal thin film dryer is heated and dried inside the centrifugal thin film dryer as described above, and as the water evaporates and the water content decreases,
Its properties change gradually. That is, depending on the conditions, in the case of ordinary sludge, as the heating and evaporation progresses, the sludge becomes liquid → soft paste → hard paste →
Change to granular.

In the conventional centrifugal thin-film dryer, when high-viscosity sludge 6 is introduced from the sludge inlet 1a, the sludge 6 is rapidly heated by steam in the steam jacket 5 at the upper part of the heat transfer drum 1. It may be rapidly solidified and dried and hardened without forming a thin film. Therefore, it is difficult to transfer heat to the inside of the solid, and the drying efficiency may be reduced.

The present invention has been made in view of the above points, and has as its object to provide, in particular, a centrifugal thin film dryer capable of efficiently drying highly viscous sludge.

[0010]

SUMMARY OF THE INVENTION The present invention is directed to a vertical heat transfer cylinder having a sludge inlet provided at an upper portion and a sludge discharge port provided at a lower portion, and a rotatable inside the heat transfer drum. A main shaft having a blade for extending the sludge supplied from the sludge inlet into the heat transfer drum to the inner surface of the heat transfer drum and drying the sludge. A heating area and a high-temperature heating area are set, and outside the heat transfer cylinder,
A centrifugal thin film dryer provided with a low-temperature heating device for a low-temperature heating region and a high-temperature heating device for a high-temperature heating region, and a sludge inlet provided at an upper portion and a sludge outlet provided at a lower portion And a blade that is rotatably provided in the heat transfer cylinder and has a blade that stretches the sludge supplied from the sludge inlet into the heat transfer drum to the inner surface of the heat transfer drum and dries. A centrifugal thin film dryer comprising: a main shaft; a heating device provided outside the heat transfer cylinder; and a heating temperature of the heating device is increased from above to below in a main shaft direction of the heat transfer cylinder. .

According to the present invention, the sludge introduced from the sludge introduction port falls downward on the inner surface of the heat transfer drum. During this time,
Contamination in the heat transfer drum is first heated by a low-temperature heating device in a low-temperature heating region, or is heated by a low-temperature heating device to lower the viscosity. The sludge having reduced viscosity becomes a thin film by rotation of the blade, and is further heated by a high-temperature heating device in a high-temperature heating zone region, or dried by being heated by a high-temperature heating device. The dried sludge is discharged from the discharge port.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a view showing one embodiment of a centrifugal thin film dryer according to the present invention.

As shown in FIG. 1, the centrifugal thin film dryer has a heat transfer cylinder 1 having a sludge inlet 1a provided at an upper part and a sludge discharge port 1b provided at a lower part. A main shaft 2 rotatably provided, and the main shaft 2 is driven by a motor 7.

A dispersing ring 3 for dispersing the sludge supplied into the heat transfer drum 1 from the sludge inlet 1a along the inner surface of the heat transfer drum 1 is provided above the main shaft 2. A plurality of blades 4 are attached along the axial direction and the circumferential direction to the thin film of the sludge dispersed on the inner surface of the heat transfer drum by the dispersion ring 3.

Since the blade 4 moves with a small gap between the blade 4 and the heat transfer drum 1, a large amount of solid content may be generated. In order to prevent this biting, the blade 4 is hinged at the root and can be bent with respect to the main shaft 2.

At the lower end of the heat transfer drum 1, a main shaft 2 is mounted on a bearing 13.
A spoke 13 rotatably supported by a is provided, and a discharge port 1 b of the heat transfer drum 1 is connected to a lower portion of the spoke 13. Further, an exhaust port 12 for exhausting steam generated from the sludge is provided above the sludge inlet 1a of the heat transfer drum 1. The heat transfer drum 1 is divided into a low-temperature heating area 15 and a high-temperature heating area 16 in the main shaft 2 direction from above to below.

Further, on the outside of the heat transfer drum 1, a hot water jacket 14 for heating the sludge is provided at a portion corresponding to the low temperature heating area 15, and the hot water jacket 14 has a temperature of 40 to 80 ° C. through a hot water inlet 14a. As the hot water flows in, the hot water in the hot water jacket 14 flows out of the hot water outlet 14b.

Further, on the outside of the heat transfer cylinder 1, a steam jacket 5 is provided at a portion corresponding to the high-temperature heating region 16 as a heat source for dehydrating and drying sludge. The steam jacket 5 has a steam inlet. The steam in the steam jacket 5 flows out from the steam outlet 5b while the steam flows in from the steam jacket 5a.

Next, a description will be given of the present embodiment having such a configuration.

The sludge 6 supplied from the sludge inlet 1a into the heat transfer drum 1 is dispersed along the inner surface of the heat transfer drum 1 by a dispersion ring 3 rotating together with the main shaft 2. Further sludge 6
Is scraped off by a blade 4 rotating together with the main shaft 2, and is stretched into a thin film on the inner surface of the heat transfer cylinder 1. The sludge formed into a thin film gradually moves downward due to gravity and the pressure of new sludge supplied one after another. During this time, the sludge 6 comes into contact with the inner surface of the low-temperature heating area 15 of the heat transfer drum 1 and is heated using the hot water supplied to the hot water jacket 14 as a heat source. In this case, the temperature of the sludge 6 gradually increases, and the viscosity of the sludge 6 decreases accordingly. The sludge 6 having reduced viscosity is converted into a blade 4 rotating with the main shaft 2.
, And is advanced to a high-temperature heating region 16 in the heat transfer drum 1. The sludge 6 comes into contact with the inner surface of the high-temperature heating area 16 and is dried using the heating steam supplied to the steam jacket 5 as a heat source.

As described above, according to the present embodiment, even if the high-viscosity sludge 6 is supplied, it is gradually heated in the low-temperature heating area 15 of the heat transfer drum 1, so that the viscosity thereof is reduced. For this reason, the sludge 6 which has become low-viscosity and thin-film without being clumped is then dried in the high-temperature heating area 16. For this reason, processing efficiency is improved, and stable operation can be performed.

Although an example in which the heat transfer cylinder is divided into a low-temperature heating area and a high-temperature heating area has been described, a heating device is provided outside the heat transfer cylinder 1 and the heating temperature of the heating device is increased from above to below. May be raised gradually.

[0023]

As described above, according to the present invention, the sludge is heated at a low temperature, the viscosity thereof is reduced, and the sludge is easily stretched into a thin film. Then, by heating at a high temperature, the sludge can be formed into a thin film without being clumped and dried. For this reason, especially, the drying treatment efficiency of highly viscous sludge can be improved.

[Brief description of the drawings]

FIG. 1 is a schematic view showing an embodiment of a centrifugal thin film dryer according to the present invention.

FIG. 2 is a schematic view showing a conventional centrifugal thin film dryer.

FIG. 3 is a plan view showing a conventional centrifugal thin film dryer.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Heat transfer cylinder 1a Sludge inlet 1b Sludge outlet 2 Main shaft 4 Blade 5 Steam jacket 14 Hot water jacket 15 Low temperature heating area 16 High temperature heating area

Claims (2)

[Claims] 1. A vertical heat transfer cylinder having a sludge inlet provided in an upper part and a sludge discharge outlet provided in a lower part, and a rotatable heat transfer cylinder provided in the heat transfer drum. A main shaft having a blade for extending and drying the sludge supplied to the inside of the heat drum to the inner surface of the heat transfer drum, wherein the inside of the heat transfer drum has a low-temperature heating region and a high-temperature heating region in the main shaft direction from top to bottom. A centrifugal thin-film dryer characterized in that a low-temperature heating device for a low-temperature heating region and a high-temperature heating device for a high-temperature heating region are provided outside the heat transfer cylinder. 2. A vertical heat transfer cylinder having a sludge inlet provided at an upper part and a sludge discharge outlet provided at a lower part; a rotatable heat transfer cylinder provided in the heat transfer drum; A main shaft having a blade for extending the sludge supplied into the heat drum to the inner surface of the heat transfer drum and drying the sludge, providing a heating device outside the heat transfer drum, and controlling the heating temperature of the heating device to the main shaft of the heat transfer drum. A centrifugal thin-film dryer characterized by being lifted downward from above in a direction.