JPS61273299A - Belt press type dehydrating device - Google Patents

Abstract

PURPOSE:To improve remarkably dehydration efficiency and to reduce the size and cost of a device by driving uppera and lower belts at least one of which is formed of a meshed member by the engagement with sprockets. CONSTITUTION:The lower belt 10 is constituted of the meshed member 11 and a filter cloth 13. The member 11 is formed by combining successively wires 12 provided alternately with Z-shaped curves 12a and inverted Z-shape curves 12b at specified intervals and formed zigzag with straight parts 12c, 12c in the longitudinal direction at the curved parts thereof into an endless belt shape. The sprockets 16, 19 are disposed. The sprockets are respectively driven when a chain 52 is driven toward an arrow by a motor 50. The lower belt 10 is driven by the engagement of the sprockets 15-20 with the member 11 and therefore the meadering of the belts 10, 30 in the transferse direction is obviated. The dehydration efficiency is thus remarkably improved.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field to Which the Present Invention Pertains The present invention relates to a dewatering device for dewatering sludge, and particularly to a belt press type dewatering device.

<Prior Art> A large amount of thickened sludge is produced from sewage treatment facilities, various industrial wastewater treatment facilities, etc., but since this thickened sludge contains a large amount of water, it cannot be disposed of as is. Therefore, a dewatering device is required to further dehydrate this thickened sludge.

As a dewatering treatment apparatus for such thickened sludge, a belt press type dewatering apparatus has conventionally been used, in which thickened sludge is sandwiched between two belts and compressed and dehydrated to form a dehydrated cake.

FIG. 1 shows an example of such a conventional belt press type dewatering device.

That is, the endless lower belt 1 and upper belt 2 made of filter cloth are driven at the same speed. Thickened sludge A is supplied onto the lower belt 1 from the chute 3.

The lower belt 1 transports the thickened sludge A, and the upper belt
and the press drum 4.4.4,...
Squeeze by... The water content of the thickened sludge A is squeezed out through both belts 1.2, and a dehydrated cake A' is formed.
and the belts 1.
It is scraped off from 2.

However, in the conventional belt press type dewatering device, the upper belt 1 and the lower belt 2 are moved by the roller 7 due to their tension.
．． Since the rack is passed between the rack 8 and the pressing drum 4 and is driven, it is necessary to have sufficient tensile strength to withstand this tension. For this reason, the belt 1.2 was constructed of a finely woven, thick filter cloth so as to maintain sufficient tensile strength.

Problems to be Solved by the Present Invention> (A) From the viewpoint of dewatering efficiency, the coarser and thinner the filter cloth constituting the belt 1.2, the better.However,
In the conventional apparatus, the idle cloth constituting the belt 1.2 has a fine mesh and is thick, resulting in extremely poor dewatering efficiency.

Therefore, in order to achieve sufficient dewatering, it is necessary to provide multiple stages of the compression drums 4 (usually more than 10 stages), which makes the entire apparatus larger, more complicated, and more expensive.

In addition, in order to improve the dewatering efficiency, some vacuum devices are installed to forcefully drop water from the bottom of the lower belt 1, but the device is complicated and expensive.

(Opening) After the attached dehydrated cake A' is scraped off, the lower belt 1 and the upper belt 2 are washed with washing water.

However, in the conventional apparatus, since the belt 1.2 is composed of a thick, fine-mesh filter cloth, a large amount of high-pressure water is required for cleaning.

Furthermore, since a large amount of washing water is required and the washing water is returned to the raw water tank, the processing efficiency of the raw water has also deteriorated.

(c) The lower belt 1 and the upper belt 2 are driven by rollers. However, the belt 1.2 holds 11 compressed sludges, and the multi-stage compression drum 4.4...
However, since the concentrated sludge A is not necessarily uniform in the width direction of the belt 1.2, the belt 1.2 gradually shifts in the width direction during driving and meanders.

For this reason, in the conventional apparatus, auxiliary devices for preventing the belt from meandering had to be installed at many locations, making the apparatus complicated.

(d) In the conventional device, the belts 1.2 are made of thick filter cloth, which makes the belts expensive, and the belts need to be replaced when they become damaged, resulting in high costs.

OBJECTS OF THE INVENTION The object of the present invention is to provide a belt press type dewatering device that solves these problems.

One Embodiment of the Present Invention> FIG. 2 is a schematic configuration diagram showing the entire belt press type dewatering apparatus according to one embodiment of the present invention.

In the figure, 10 is a lower belt.

The lower belt 10 has a mesh member 11 as shown in FIG.
and a filter cloth 13.

As shown in Fig. 4.6, the mesh member 11 has double-shaped curved portions 12a and inverted Z-shaped bent portions 12b alternately provided at two constant intervals, and straight portions 12c and 12c' at different levels. The formed wires 12 are successively combined in the longitudinal direction of the belt 10 at their bent portions to form an endless belt.

As shown in FIG. 3.6, filter cloths 13 are fixed with fasteners 14 at predetermined intervals at both ends of the mesh member 13 in the width direction. The filter cloth 13 is made of thin, coarse cloth.

This lower belt 10 has a mesh member 11 inside and a filter cloth 13 inside.
The frame is extended so that the straight portions 120112C' of the mesh member 11 are engaged with the crests of the sprockets 15 to 20, with the sprockets 15 to 20 facing outward.

As shown in FIG. 5, the sprocket 15 has a shaft portion 15a.
sprocket portions 15b are formed at regular intervals,
As shown in FIG. 6, the tooth portion 15 of each sprocket portion 15b
b' engages with the straight portions 12c and 12C' of the wire 12 of the mesh member 11 of the lower belt 10. The sprocket 15 is rotatably attached to the frame 21 at the take-up portion of the lower belt 10.

The sprockets 16, 19, and 20 have the same shape as the sprocket 15, and are rotatably attached to the frame 21. The sprocket 16 is located between the take-up portion of the lower belt 10 and a compression drum 38 (described later), and the sprocket 19 is located immediately after the compression drum.
0 is located at the return portion of the lower belt 10.

As shown in FIG. 5, the sprocket 17 has a shaft portion 17a.
two straight parts 1 at each end of the wire 12 near both ends of the wire 12
A sprocket portion 17b that meshes with 2c and 12c is provided. As shown in FIG. 2, this sprocket 17 is rotatably attached to the frame 21 at a position immediately before the compression drum 38.

The sprocket 18 has the same shape as the sprocket 17 and is attached to the frame 21 at the lower surface of the compression drum 38.
It is rotatably mounted on the

22 is a roller that contacts the filter cloth 13 of the lower belt 10 from below at the return portion of the lower belt 10.

As shown in Fig. 2.7.8, 24 is a scum chute for supplying the concentrated sludge A to the lower belt 10. II Shrinking sludge) A is received at the mouth 2
The receiver is put in from 4a and discharged from the lower outlet 24b. The discharge port 24b is provided with sludge prevention skirts 27a and 2 to prevent the concentrated sludge A from spilling from the lower belt 10.
7b are provided on both sides in an inverted C-shape. skirt 27
Thin elastic bodies such as rubber are attached to the tips of a and 27b.

Further, below the scum chute 24, sliding rails 28a to 28a extend in the length direction of the lower belt 10 at the center and both ends of the lower belt 10 in the width direction.
28c is provided.

Near the sprocket 19 at the rear of the compression drum 38,
A scraper 29 is installed to scrape off the dehydrated cake A' adhering to the filter cloth 13 of the lower belt 10.

In FIG. 2, 30 is an upper belt.

The upper belt 30 is composed of two endless mesh members 31 and a filter cloth 33, as shown in FIG.

As shown in FIG. 10, the mesh member 31 includes a wire 32 having a Z-shaped bent portion 32a and an inverted Z-shaped bent portion 32b at both ends □.
a and 32b are combined to form an endless belt.

As shown in FIG. 9, two mesh members 31 and 31 are fixed to both ends of the filter cloth 33 in the width direction with fasteners 34 at a predetermined interval. The filter cloth 33 is made of a material whose mesh is slightly finer than that of the filter cloth 13 of the lower belt 10.

This upper belt 30 has the mesh member 31.31 on the inside and the filter cloth 33 on the outside, and the straight portion 32c of the mesh member 31.31.
sprocket rollers 35 to 37 and compression drum 38
The rack is passed so that the teeth of the two mesh together.

As shown in FIG. 8, the sprocket roller 35 has sprocket parts 35b and 3 at both ends of a roller part 35a.
5b is formed, and the teeth of each sprocket portion 35b are connected to the wire 32 of the mesh member 31.31 of the upper belt 30.
It meshes with the straight line portion 32c.

Sprocket rollers 36, 37 also have the same shape as sprocket roller 35.

As shown in FIGS. 2 and 5, the compression drum 38 has sprocket parts 38b and 38b at both ends of the drum part 38a.
, whose teeth are connected to the mesh member 3 of the upper belt 30.
It meshes with the straight part 320 of Y V-32 of No. 1 and 31.

A roller 39 is in contact with the filter cloth 33 side of the upper belt 30.

The sprocket rollers 35 to 37, the compression drum 38, and the roller 39 are rotatably attached to the frame 21.

The upper belt 30 is located near the sprocket roller 37.
A scraper 40 is installed to scrape off the dehydrated cake A' adhering to the filter cloth 33.

In FIG. 2, 50 is a motor for driving the upper belt 10 and the lower belt 30. The sprocket provided on the drive shaft of this motor 50 and the sprocket 51
A chain 52 is passed between one sprocket and a sprocket provided coaxially with the sprocket roller 37.

Therefore, when the motor 50 drives the chain 52 in the direction of the arrow, the sprocket 19 is driven clockwise and the sprocket roller 37 is driven counterclockwise, thereby causing the lower belt 10 to move in the direction of arrow B and the upper belt 30 to move in the direction of arrow B. It is driven in the C direction at the same speed.

Following the drive of the lower belt 10, the sprockets 15, 16, 17, 20 meshed with the mesh member 11 are driven. Similarly, the sprocket roller 3 follows the drive of the upper belt 30 and meshes with its mesh member 31.31.
5.36 and the squeeze drum 38 are driven.

A dehydrated cake storage container 41 is installed below the scrapers 29 and 40.

42. 43 is a washing tank provided below the lower belt 10° and the upper belt 30 to collect water; 44 is a pipe;
5 is a pump that pumps up the washing water in the washing water tank 42. Reference numerals 46 and 47 indicate nozzles that spray washing water pumped up by the pump 45 to the lower belt 10 and the upper belt 30, respectively, for washing. The washing water tank 42 is provided with an overflow outlet 48 for returning surplus water to the raw water tank (not shown) of the flotation separation device 25.

Operation of the above embodiment> Next, the operation of the above embodiment will be explained.

When the motor 50 is powered on, the chain 52 forcibly drives the sprocket 19 and the sprocket roller 37. Therefore, the teeth of the sprocket 19 mesh with the mesh member 11 of the lower belt 10, and the lower belt 1
0 in the direction of arrow B. Similarly, the teeth of the sprocket roller 37 mesh with the mesh members 31, 31 at both widthwise ends of the upper belt 30, driving the upper belt 30 in the direction of arrow C at the same speed as the lower belt 10.

The flocculated and concentrated sludge A scraped out by the skimmer 26 of the flotation separator 25 is stored in the scum chute 24, but as the lower belt 10 moves in the direction B, the lower belt 10 is discharged from the discharge port 24b. It is fed onto the filter cloth 13. Thick mud prevention skirts 27a, 2 are provided on both sides of the discharge port 24b.
7b, the liquid is discharged onto the lower belt 10 without leaking in the width direction of the lower belt 10.

As the lower belt 10 moves in eight directions, the thickened sludge A is uniformly supplied onto the lower belt 10 in this manner and advances toward the pressing drum 38.

Since the filter cloth 13 is supported by the mesh member 11, it is made of a sufficiently thin and coarse mesh material, so that the filter cloth 13 is supported by the mesh member 11.
8, water in the thickened sludge A passes through the filter cloth 13 and drips downward. The dropped water is collected in a washing water tank 42.

When the lower belt 10 advances to the sprocket 17, it is combined with the upper belt 30 from above, and the thickened sludge A is transferred to both belts 10.
, 30, and is strongly compressed from the upper belt 30 side by the pressing drum 38, and passes through while being dehydrated.

As mentioned above, since the filter cloth 13.33 is sufficiently thin and has a coarse mesh, water can be removed more dramatically than in conventional devices. The water dehydrated in the pressing drum 38 falls into a washing water tank 42.

During this time, the sprockets 17 and 18 engage with both ends of the mesh member 11 of the lower belt 10 in the width direction.

Therefore, the center of the lower belt 10 supported on both sides is in a swollen state, and even if strongly compressed by the squeezing drum 38, no leakage will occur from the sides of the belt 10.30.

In addition, the lower belt 10 has sprockets 15 on the mesh member 11.
20 are engaged and driven, and the upper belt 30 is also connected to the 15th member 31 and the sprocket roller 35.
37 are engaged and driven, belt 10.3
No deviation or meandering in the width direction occurs during driving.

In this way, the concentrated sludge A is compressed by the compressing drum 38 and becomes a dehydrated cake A', which remains attached to the filter cloths 13 and 33 of the lower belt 10 and the upper belt 30 and is transferred to the sprocket 1.
9, it advances to the sprocket roller 37, is scraped off by scrapers 2, 9, and 40, and falls into the dehydrated cake storage container 41.

The cleaning water accumulated in the cleaning water tank 42 is pumped up by a pump 45 and sprayed from a nozzle 46 onto the lower belt 10 and from a nozzle 47 onto the upper belt 30 for cleaning. Since the filter cloth 13.33 is thin and has a rough mesh, it is easy to clean.

The cleaning water sprayed onto the upper belt 30 is collected in a cleaning tank 43 and discharged from the vibrator 44 into the cleaning tank 42. The cleaning water sprayed onto the lower belt 10 is collected in a cleaning water tank 42. In this way, the cleaning water in the cleaning water tank 42 is circulated and used for cleaning the belt 10.3o. When the cleaning water in the cleaning water tank 42 reaches a predetermined height, the overflow drain port 4
8 and returned to the raw water tank (not shown) of the flotation separator 25.

(Example) Next, examples of dewatering using the belt press type dehydrator of the present invention are as follows.

With conventional equipment, the moisture content of the dehydrated cake can be reduced to 90% at most.
Whereas it was only possible to achieve a reduction of 80%, the present invention was able to achieve a reduction of 75 to 65%.

Note that, as shown in FIG. 11, if the pressing drums 38 are provided in two stages, the dewatering efficiency is further improved.

Note that 53 and 54 are sprockets having the same shape as the sprocket 19.

In addition, although the compression drum 3B is shown as having sprocket parts 38b and 38b at both ends in FIG. The pressing drum 38 may be caused to follow the upper belt 30 by rubbing against the upper belt 30.

<Effects of the present invention> The belt press type dewatering device of the present invention has the following effects.

(b) Unlike conventional devices in which the belt is driven across the frame by the tension of the filter cloth itself, in the present invention, the belt is driven by the meshing of the mesh member and the sprocket,
No tension is required on the filter cloth. Therefore, in the present invention, the filter cloth can be made as thin as possible and made of coarse mesh, so that the dewatering efficiency is dramatically improved.

(0) For this reason, the number of stages of compression drums required in conventional equipment is reduced to just one or at most two stages, and there is no need for conventional vacuum devices to improve dewatering efficiency. The entire device can be significantly downsized and costs can be reduced.

(c) Since the filter cloth is made of thin and coarse mesh, it is easy to clean, and not only does it not require high-pressure water like conventional devices, but also the cleaning water can be recycled.
There is also less need for washing water.

(d) Since the belt is driven by the meshing of the mesh member and the sprocket, deviation or meandering in the width direction of the belt is completely prevented. Therefore, unlike the conventional device, there is no need to provide a meandering prevention device, and the entire device can be made smaller and lower in cost.

(E) The filter cloth of the belt can be thin and coarse, resulting in low cost, and since the filter cloth is attached to the mesh member, the filter cloth can be easily replaced.

(f) The filter cloth is thin and made of coarse mesh, and has good dewatering efficiency, so the belt drive speed can be increased compared to conventional equipment, resulting in a dramatic increase in throughput. .

[Brief explanation of drawings]

FIG. 1 is a schematic mechanical diagram showing the main parts of a conventional belt press type dewatering device, FIG. 2 is a schematic mechanical diagram showing the overall configuration of an embodiment of the present invention, and FIG. 3 is a schematic diagram showing the configuration of the lower belt. 4 is a plan view showing the configuration of the mesh member of the lower belt, FIG. 5 is a schematic plan view showing the lower belt drive mechanism and the pressing drum, and FIG. 6 is a cross section showing the relationship between the sprocket and the lower belt. Fig. 7 is a cross-sectional view schematically showing the scum chute and its surroundings, Fig. 8 is a schematic plan view showing the upper belt drive mechanism and the scum chute, and Fig. 9 is a schematic plan view showing the structure of the upper belt. , FIG. 10 is a plan view showing the mesh member of the upper belt, and FIG. 11 is a schematic mechanical diagram showing the main parts of another embodiment of the present invention. 1... Lower belt, 2... Upper belt, 3... Chute, 4... Pressing drum, A... Thickened sludge, 10 ...Lower belt, 11...Mesh member, 12...Wire, 13...Filter cloth, 14...Zipper, 15-20 ...Sprocket, 21...
...Frame, 22...Roller, 24.
... Scum chute, 25 ... Flotation separation device, 26 ... Skimmer, 27a127b ...
...Thick mud prevention skirt, 28a, 28b. 28c...Sliding rail, 29...
...Scraper, 30...Top belt, 3
1...Mesh member, 32...Wire,
33...Filter cloth, 34...Zipper,
35-37...Sprocket roller, 38.
.....pressing drum, 3 .....roller, 4
0...Scraper, 41...Dehydrated cake storage container, 42.43...Washing tank, 44
... Vibrator, 45... Pump, 46.
47...Nozzle, 48...Overflow drain port, 50...Motor, 52...
·chain. Patent Applicant Sugihara - Toyokino 1) Hide Yasu Agent Patent Attorney Makoto Hayakawa Figure 2N Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 10 Figure 11

Claims (1)

[Scope of Claims] A belt press type dewatering device in which sludge is sandwiched between a lower belt and an upper belt, and a compression drum presses both belts from one side to compress and discharge water in the sludge; At least one of the belts is composed of a mesh member that is driven to engage with the sprocket, and a filter cloth that is attached to the mesh member on the opposite side of both belts, and the belt is driven by the mesh member and the sprocket. A belt press type dewatering device characterized by being designed to