JPS6049893A - Sludge dehydrator - Google Patents

Abstract

PURPOSE:To enable efficient dehydration by making pressing rolls circumferentially movable in the position thereof by the circumferential surface of a main roll thereby changing the face pressure to exert a high pressure on sludge. CONSTITUTION:A filter cloth belt A and at the same time an auxiliary belt 14 are conducted to turning rolls 8, 8' on an inlet side and an outlet side in such a way that the belt 14 is pressed to the circumferential surface of a main roll 7 and the belt A is pressed to the main roll 7. The belts are turned by the roll 8' to return to the roll 8. The belt A is further pressed under high pressure by the belt 14 to the roll 7 and is also pressed by a press roll 9. The position of the roll 9 is movable circumferentially by the circumferential surface of the roll 7 and therefore the face pressure is made successively higher from the sludge supply side, by which efficient dehydration is made possible.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a sludge dewatering device, and particularly to an improvement in a high-pressure dewatering section provided in a belt press type dewatering device.

Conventionally, as shown in Figure 1, main roll 1 auxiliary belt 2
Also known is a system that performs high-pressure dehydration using a tensioning device 3. Generally, when the tension of the auxiliary belt is F kg/cTL and the radius of the main roll is r, the surface pressure P is expressed as P=F/r.

The practical tension of the auxiliary belt is currently + o otcg
/an is the limit, and the diameter of the main roll is also limited to 20 cm due to restrictions when wrapping the auxiliary belt.
It is difficult to make it smaller. Therefore, the current limit of the surface pressure of the high-pressure dewatering section as shown in FIG. 1 is approximately skg/d1. In order to improve this, the applicant filed a patent application filed in 1983.
No. 156344 (Japanese Unexamined Patent Publication No. 56-81114) proposed a method as shown in FIG. 2 in which an auxiliary belt 2 is wound around the main roll l to further utilize the tension of the folded auxiliary belt. in this case.

Since the auxiliary belt is double-layered, the surface pressure can be expected to be around xokg/d.
It is necessary to intervene. For this reason, although a surface pressure of more than 10Ic9/c1'l is applied to the roller portions, the surface pressure decreases to the contrary in the portions without the rollers, resulting in uneven surface pressure as a whole. Therefore, there are inconveniences such as severe clogging of the f cloth and inability to dewater efficiently. To provide a high-pressure dewatering section in a sludge dewatering device that can be strongly applied with surface pressure and can have surface pressure several steps higher than conventional ones.

The present invention will be described below with reference to the drawings.

Belt press type sludge dewatering equipment is of the type shown in Fig. 3, which uses two endless r-cloth belts A and B for pressure dewatering, and the type which uses one endless belt (P) as shown in Fig. 4. There is a method that performs pressurized dewatering using only cloth bell A, but in any case, in front of the pressurized dewatering section 5, there is one sheet of F cloth cloth that performs gravity dewatering while advancing a straight belt. Next, after pressure dehydration is performed in the pressure dehydration section 5, the dehydrated cake is peeled off from the P cloth belt. The present invention may be applied to any of these types of dehydration equipment. In other words, any device having a pressurized dewatering section can be used, but here, the pressurized dehydration will be described using a one-piece fabric belt shown in FIG. 4. 7 is the main roll, 8 is the inlet side turning roller, and 8' is the outlet side turning roller.

9 is a pressure roller, 10 is a meandering correction roller, 11 is a slurry supply device, 12 is a dewatered cake peeling scraper 13, a roller around which the R cloth belt is wound, and 14 is an auxiliary belt made of, for example, a wire mesh.

In such a device, tempered sludge is first supplied to the sludge packing 11, water is dehydrated by gravity as the F cloth bell (A) advances on the straight belt or 6, and then the water is removed by gravity at the inlet side turning roll 8. The cloth belt turns and dewaters under pressure while pressing the sludge against the main roll 7, and the dehydrated cake is transferred to the scraper 12.
It is peeled off and discharged. Thereafter, the P cloth belt A is turned again by the exit side turning roll 8', loops around the 70-ra 13, and returns to the mud supply position for circulation. At the entrance and exit side turning rolls, an auxiliary bell (14) is guided to the circumferential surface of the main roll 7 so as to press the cloth belt against the main roll, and is turned by the exit side turning roll. It is provided so that it circulates back to the inlet side turning roll. When the auxiliary belts 14 circulate, a pressure roll with a small diameter is provided to prevent the auxiliary belts running in different directions from coming into direct contact with each other. At least one of the deflection rolls on the inlet side or the outlet side can be moved upwardly by any means to tension the auxiliary belt. As a result, the auxiliary bellows cloth belt can be further pressed against the main roll at a high pressure, and pressing can also be performed using a pressure roll.

However, the pressure roll, which has a small diameter, allows its position to be moved in the circumferential direction on the surface of the main roll. Although not shown, this moving means, as proposed by the present applicant in Japanese Patent Application No. 58-23848, includes an upwardly extending piece provided on a bearing supporting the shaft at each end of the pressure roll. The upper end may be pivotally attached to each side wall on both sides of the device so that it can swing seven times, and it may be fixed at an appropriate position. In the case of the device of the present invention, the force pressing each separate pressure roll against the main roll is the force of the auxiliary belt F kg/cm as shown in Fig. 5, and when the auxiliary belt returns while contacting the pressure roll. The angle αC of the winding around the pressure roll and (-1 if the weight of the pressure roll is ignored, the width I Cm of the auxiliary belt α is j: l 2 , F, 51n −kg, and the tension of the auxiliary belt and It is determined by the wrapping angle. Therefore,
By moving the pressure roll and changing the wrapping angle, it is possible to gradually change the surface pressure, that is, to gradually increase the surface pressure from the sludge supply side, and it is also possible to apply high pressure. This enables efficient dehydration. In fact, in the case of the present invention, at least one of the turning rolls on the inlet π(1) or the outlet side is used as a tension roll, so there is no need to provide a separate tension roll.

[Brief explanation of drawings]

Figures 1 and 2 are schematic diagrams of a conventional high-pressure dewatering section;
4 and 4 are schematic diagrams of a dewatering device using a high-pressure section of the present invention, and FIG. 5 is a diagram explaining the principle of surface pressure. In the figure, 7 is a main roll, 8 is a turning roll on the inlet side, and 8' is on the outlet side turning roll,
There are 9 pressure rolls and 14 is an auxiliary belt. Patent issued) Tonjin Kurita Kosu Co., Ltd. Figure 1 Figure 2 Down 3 times 4th item 1go 5th doctor

Claims (1)

[Claims] (11 After arranging multiple small-diameter pressure rolls on the circumference of a large-diameter main roll, and guiding an endless one-fabric belt to the circumference of the main roll and passing between the circumference and the pressure rolls, In a sludge dewatering device that circulates and returns sludge to the sludge supply position around the pressure roll in the final stage, the sludge is passed between the cloth belt led to the circumference of the main roll and the pressure roll, and then heated to the exit side. An auxiliary belt is provided to press each pressure roll against the main roll, and the pressure roll is brought into contact with the pressure roll in a folded manner and returned to the pressure roll on the inlet side. At least one of the rolls is movable in any direction to tension the auxiliary belt, and the position of the pressure rolls other than the roll can be adjusted by moving in the circumferential direction on the circumferential surface of the main roll. Sludge dewatering equipment.