JPS6239917Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a belt press type dehydrator in which a pair of endless belt-shaped rotary filter cloths sandwiching a workpiece are wound in a zigzag pattern around parallel rolls.

In the above-mentioned dehydrator, the squeezing force of both filter cloths is maintained almost constant by the tensioning roll, and the dewatering performance is also uniquely defined accordingly. Therefore,
In order to increase the clamping pressure to sufficiently reduce the moisture content, it is necessary to apply high tension to the filter cloth, but if the operation is continued with high tension applied, the filter cloth will stretch prematurely and The drawback was that it had a short lifespan.

In view of the above points, it is an object of the present invention to make it possible to satisfactorily increase the clamping force of both filter cloths while avoiding a reduction in the service life of the filter cloths.

Next, embodiments of the present invention will be described in detail based on illustrative drawings.

The processed material supplied from the first storage tank 1 and the second
A mixer 3 is provided to coagulate and mix the flocculant supplied from the storage tank 2, and a gravity dewatering section 5 is attached to the endless belt-shaped first rotary filter cloth 4, and the direction of rotation of the gravity dewatering section 5 is A forced dewatering section 7 is provided on the lower side to compress the thickened sludge in cooperation with the second rotary filter cloth 6, and as the first and second rotary filter cloths 4 and 6 rotate,
The belt press type dehydrator is configured to continuously dewater treated materials such as sludge generated in various water treatments such as human waste, urban sewage, and industrial wastewater.

The forced dewatering section 7 includes a constrictive dewatering zone A having a linear path, a compressive dehydrating zone B having a large diameter arcuate path, and a shear dehydrating zone C having a meandering path. The structure is such that the clamping force by the moving filter cloths 4 and 6 is increased sequentially.

A scraper 8, which is an example of a cake collecting tool, is attached to each of the first and second rotary filter cloths 4 and 6 on the downstream side of the forced dewatering section 7 in the filter cloth traveling direction, for peeling off cake stuck thereto. With,
A conveyor 9 is provided below the scrapers 8, 8 to collect the peeled dehydrated cake.

In the shear dehydration zone C, a single-acting air cylinder 11 is interlocked with both bearing holders 10a and 10b of one of the rolls 10 for forming a zigzag path, and a compressor 12 is connected to the air cylinder 11. A rotary valve 14 of an electromagnetically operated type is interposed in the middle of the air passage 13, and the rotary valve 14 is automatically operated by a control device 15 to supply air to the air cylinder 11. and displaces the roll 10 in the tension direction of the filter cloths 4 and 6, and also stops the air supply to the air cylinder 11 and releases air from the air cylinder 11 to the atmosphere to move the roll 10 to the tension direction of the filter cloths 4 and 6. The structure is such that the filter cloths 4 and 6 are automatically switched to a state in which they are displaced in the relaxation direction at set time intervals, and the clamping force against the object to be processed by the filter cloths 4 and 6 is intermittently increased to sufficiently lower the water content.

In the control device 15, as shown in FIG. 3, the time is set so that a tense state a for about 3 seconds and a relaxed state b for about 18 seconds are alternately obtained. The time for this tense state is preferably set to within 5 seconds, and the time for the relaxed state is preferably set to at least five times the time for the tense state.

To drive and displace the roll 10, various modifications are possible, such as using a hydraulic cylinder instead of the air cylinder 11.
Collectively called.

The present invention is not limited to one roll 10,
Two or three rolls 10... may be driven and displaced.

In summary, the present invention provides, in the above-mentioned belt press type dehydrator, a drive mechanism 11 for displacing at least one of the rolls 10 in the tensioning direction and loosening direction of the filter cloths 4 and 6. It is characterized in that it is provided with a control device 15 that is interlocked and connected and automatically causes the drive mechanism 11 to reciprocate at every set time.

In other words, the filter cloths 4 and 6 are switched between a relaxed state and a tensioned state at set time intervals to forcibly change the pressure applied to the object to be processed, and the pressure changes greatly when switching from the relaxed state to the tensioned state. This applies a high clamping force to the object to be processed.

Therefore, it is possible to prevent the filter cloths 4 and 6 from elongating due to the application of tension without constantly applying high tension to the filter cloths 4 and 6, and to avoid a decrease in their service life.
It has now become possible to satisfactorily increase the clamping force on the workpiece and sufficiently reduce the moisture content.

[Brief explanation of the drawing]

The drawings show an embodiment of the belt press type dewatering machine according to the present invention, in which Fig. 1 is a general schematic vertical sectional view, Fig. 2 is a partially cutaway view taken along the line - in Fig. 1, and Fig. 3 is a time chart. It is. 4, 6... Filter cloth, 10... Roll, 11... Drive mechanism, 15... Control device.

Claims (1)

[Scope of utility model registration request] It is a belt press type dehydrator in which a pair of endless belt-shaped rotary filter cloths 4 and 6 sandwiching the processed material are wound in a zigzag shape around rolls 10 arranged in parallel, and among the rolls 10... A drive mechanism 11 is interlocked to at least one of the filter cloths 4 and 6 to displace it in the tensioning direction and relaxation direction of the filter cloths 4 and 6, and a control device 15 is provided that automatically reciprocates the drive mechanism 11 at set time intervals. A belt press type dehydrator characterized by the fact that it is attached.