JPH0245559B2 - - Google Patents

Description

[Detailed description of the invention] This invention relates to a dehydrator.

As devices for dewatering water-containing sludge generated in sewage treatment facilities, etc., belt press type devices and filter press type devices are known as typical devices.

The belt press type has a structure in which sludge is sandwiched between a pair of running cloths and dewatered by continuously winding the sludge around a roll. This belt press type has a large processing capacity because it can perform continuous dehydration, but
The drawback is that the water content of the dehydrated cake is high because the pressing pressure is low.

On the other hand, the filter press type has a structure in which sludge is sealed in a pressurizing chamber, dehydrated by applying high pressure, and then the pressurizing chamber is opened to discharge the dehydrated cake. In the case of this configuration, a large squeezing pressure can be obtained, but dehydration cannot be performed continuously and batch processing is required, so there is a drawback that the processing capacity is low.

The present invention aims to eliminate the drawbacks of the conventional belt press type and filter press type described above, and to provide a dewatering machine that has a large squeezing pressure, can process continuously, and has a high overall dewatering efficiency. Its basic features include a gravity dewatering section that primarily dehydrates high water content sludge, and a pair of rolls with uneven teeth, which receive the sludge discharged from the gravity dewatering section and process it into udon. A forming machine is installed on the sludge discharge side of the gravity dewatering section in order to form and discharge the sludge into a shape.
a pair of endless cloths consisting of an endless cloth and a second endless cloth that sandwiches sludge between the first endless cloth, and receives the sludge discharged from the forming machine and transfers it onto the first endless cloth. A moving conveyor is disposed between the forming machine and the first endless cloth so as to be able to move horizontally in the longitudinal direction of the first endless cloth, and the sludge sandwiched between the pair of endless cloths is pressurized. The present invention includes a high-pressure dehydration mechanism that compresses and dehydrates the cloth at high pressure using a plate, and a drive mechanism that stops moving the cloth when the high-pressure dehydrator is compressing and dewatering, and moves the cloth when it is not being compressed and dehydrated.

Embodiments of the present invention will be described below based on the drawings.

In FIG. 1, 1 is a gravity dewatering section, 22 is a forming machine, 2c is a moving conveyor, 3a and 3b are endless cloths, and 4 is a high pressure dewatering mechanism.

The gravity dewatering section 1 consists of a belt conveyor-like cloth 11 wrapped around rolls 10, 10,
The sludge is placed on one end and dewatered by gravity as it moves to the other end. The present invention is provided with the forming machine 22 to form and process sludge. However, in many cases, sludge with a high water content cannot be formed properly as it is, and the formation of sludge by the forming machine is limited to this process. This is possible by dehydrating to some extent using the gravity dewatering section 1.

The forming machine 22 is provided on the sludge discharge side of the gravity dewatering section 1. This forming machine 22 has a pair of rolls 220 with uneven teeth, and is configured to receive the sludge discharged from the gravity dewatering section 1, form it into a udon shape, and discharge it. By forming the sludge X in this manner, water paths are created between the formed sludge, and drainage is smoothly carried out from there.

Of the pair of endless cloths, the first endless cloth 3b runs horizontally below the forming machine 22 and receives the sludge supplied from the forming machine. This endless cloth 3b is combined with the upper second endless cloth 3a at the position of the pinch roll 30, and is led to the high-pressure dewatering mechanism 4 with the sludge X sandwiched therebetween. The endless cloth that has exited the dewatering mechanism 4 is again divided into upper and lower parts, and the sludge cake Y after dewatering is discharged. Scrapers 31, 31 for scraping off sludge adhering to the upper and lower endless cloths 3a, 3b are installed near the discharge section. Further, cloth cleaning devices 32, 32 are disposed at appropriate positions on the upper and lower endless cloths 3a, 3b, and are configured to clean the endless cloth 3.

The moving conveyor 2c is disposed between the forming machine 22 and the first endless cloth 3b so as to be movable horizontally with respect to the longitudinal direction of the first endless cloth, and carries the sludge discharged from the forming machine. received,
It is configured to be able to uniformly supply this onto the first endless cloth 3b.

In an apparatus having a high-pressure dewatering mechanism equipped with a pressure plate as in the present invention and having the gravity dewatering section 1 as described above in the preceding process, the high-pressure dehydrating section side is The endless cloth is run and stopped intermittently, and dewatering is performed by pressing with a pressure plate while it is stopped. On the other hand, in order to effectively perform high-pressure compression using an endless cloth and a pressure plate, it is necessary to constantly and uniformly supply the sludge discharged continuously from the gravity dewatering section onto the endless cloth that runs intermittently. There is. In addition, if the sludge formed into a udon-like shape by the forming machine 22 is not stored in a hopper or the like and immediately supplied onto the cloth, its shape will collapse and there will be no time left, and there will be no point in forming the sludge. Put it away.

The moving conveyor 2c was provided from this point of view, and with this moving conveyor 2c,
The udon-like sludge discharged from the forming machine 22 is immediately dropped onto the cloth, and
The moving supply of the moving conveyor 2c makes it possible to uniformly supply udon-like sludge onto the cloth regardless of the intermittent running of the cloth.

The high-pressure dewatering mechanism 4 is composed of a plurality of pressure plates 40 and a plurality of return rolls 41, and the endless cloth 3 is meandered by the return rolls 41, during which compression is performed by the pressure plates. The pressure plate 40 is provided with a hydraulic mechanism, etc., and is configured to pinch the endless cloth 3 from the left and right sides and compress it under high pressure, and this may be the same configuration as that in the conventional filter press type.

A drive mechanism (not shown) is provided in a suitable part or all of the return roll 41, and while the endless cloth 3 is being compressed by the pressure plate 40, the running of the endless cloth 3 is stopped, and the endless cloth 3 is not compressed. Sometimes the endless cloth 3 is moved.

In addition, in the dehydration mechanism 4, normally 5
A pressure of Kg/cm ² is applied for a period of 60 seconds or more.

Next, the operation will be explained.

Slud It is discharged. The moving conveyor 2c moves from left to right in the figure and uniformly supplies the sludge X to a predetermined range (length) on the endless cloth 3b while changing the falling point. During this time, the high-pressure dewatering mechanism 4 squeezes the endless cloths 3a and 3b sandwiching the sludge to dewater. When the pressurization in the high-pressure dehydration mechanism is finished, the pressurization in the high-pressure dehydration mechanism 4 is released, and the endless cloth 3 is caused to travel by approximately the travel distance of the moving conveyor by the drive mechanism. At this time, sludge cake Y is discharged. The moving conveyor 2c is also returned to its original position. Then, the endless cloth 3 is again processed by the high-pressure dehydration mechanism 4.
While compressing and dewatering the sludge, sludge is supplied from the moving conveyor 2c onto the endless cloth 3b, and the same operation is repeated thereafter.

In this case, the endless cloth 3 has a high-pressure dewatering mechanism 4
Since the fabric 3 moves little by little and is sequentially dehydrated by the plurality of pressure plates 40, there is no uneven dehydration depending on the position of the cloth 3, and uniform dehydration is performed.

Note that during the above operation, the cloth 3 is cleaned by the scraper 31 and the cloth cleaning device 32 even while pressurized.

According to the present invention described above, the gravity dehydration mechanism and the
By combining a high-pressure dehydration mechanism using a pair of endless cloths and a pressure plate, it is possible to obtain dehydration performance comparable to that of a filter press, although it is a continuous process similar to that of a belt press type.

Furthermore, in the present invention, the sludge is first lightly dehydrated in the gravity dewatering section, then formed into a udon-like shape in the forming machine, and then immediately dropped and supplied onto the first endless cloth by the moving conveyor, so that the sludge is continuously Because the sludge is supplied onto the cloth in small pieces rather than on one side, countless gaps are created in the sludge on the cloth, which become water channels from which water in the sludge drains extremely smoothly. will be discharged. In addition, sludge contains a relatively large amount of impurities such as fibers, and the presence of these impurities is a major cause of hindering the discharge of sludge-containing water, but in the present invention, sludge treatment using a forming machine This acts to loosen impurities such as fibers, and this also facilitates the smooth discharge of sludge-containing water.

In high-pressure dewatering using an endless cloth, it is desirable that the sludge supplied onto the cloth be effectively dehydrated by gravity before being compressed and dewatered, and if this is achieved, the overall dewatering efficiency can be greatly increased. In this regard, in the present invention, as described above, by processing the sludge using a forming machine having a pair of rollers with concave and convex teeth, the formation of gaps in the sludge that should become water channels, and the treatment of impurities that obstruct drainage. At the same time, the water in the sludge can be discharged very smoothly on the cloth, and the dewatering efficiency of the sludge can be effectively improved.

In addition, in the present invention, a uniform udon-like sludge can be supplied onto the cloth regardless of the intermittent running of the cloth due to the moving supply of the moving conveyor, thereby making it possible to appropriately perform high-pressure squeezing by the pressure plate. can.

[Brief explanation of the drawing]

FIG. 1 is a front view showing an embodiment of the present invention. In the figure, 1...Gravity dewatering section, 2c...Moving conveyor, 3a, 3b...Endless cloth, 4...High pressure dewatering mechanism, 22...Forming machine, 220...Roll.

Claims (1)

[Claims] 1. It has a gravity dewatering section that primarily dewaters high water content sludge, and a pair of rolls with uneven teeth, which receives the sludge discharged from the gravity dewatering section and forms it into a udon shape and discharges it. A forming machine provided on the sludge discharge side of the dewatering section, a first endless cloth that receives the sludge discharged from the forming machine, and a second endless cloth that sandwiches the sludge between the first endless cloth. In order to receive the sludge discharged from the pair of endless cloths and the forming machine and to drop and supply the sludge onto the first endless cloth, a first endless cloth is provided between the forming machine and the first endless cloth in the longitudinal direction. a moving conveyor that can be moved horizontally, and a high-pressure dewatering mechanism that compresses and dewaters the sludge sandwiched between a pair of endless cloths under high pressure using a pressure plate.
A dewatering machine characterized by having a drive mechanism that stops moving the cloth during press dehydration by the high-pressure dehydration mechanism and moves the cloth during non-press dehydration.