JPS592957Y2 - Screw press type dehydrator - Google Patents

Description

[Detailed description of the invention] The present invention uses sludge generated during the clarification of water, wastewater, and other liquids, or flocculated sludge obtained by adding organic polymer flocculants or other flocculants to these sludges and flocculating them. A screw press consisting of an outer cylinder of cylindrical furnace material and an inner cylinder of conical cylindrical furnace material, which can continuously compress and dehydrate water using screw blades and squeeze out the filtrate to produce a dehydrated cake with extremely low water content. This paper concerns improvements to type dehydrators.

As shown in Fig. 1, the conventional screw press has an outer cylinder 3' made of a cylindrical material provided between the sludge supply port 1' of the sludge hopper 2' and the dewatered cake discharge port 6', and an outer cylinder 3' on the outer periphery. a screw shaft 5' having screw blades 4';
Moreover, the volume of the annular gap between the outer cylinder 3', the screw shaft 5', and the screw blade 4' is appropriately reduced, and the sludge introduced into the sludge supply port 1' is dewatered in the axial direction by the rotation of the screw shaft 5'. It has a structure and function in which the cake is extruded and squeezed sequentially in the direction of the cake discharge port 6', the liquid squeezed out from the sludge is discharged from the cylindrical furnace material outer cylinder 3', and the dehydrated cake is taken out from the dehydrated cake discharge port 1. are doing.

Generally, in press dewatering of sludge, the smaller the amount of solids per furnace material area, that is, the smaller the amount of solids loaded, the easier the dewatering becomes.

In other words, when producing a dehydrated cake with a constant moisture content, the thinner the input sludge is, the faster the dewatering will be completed, and if the pressing time is constant, the moisture content of the resulting dehydrated cake will be higher. There is a tendency to decline.

In other words, when dewatering sludge in a conventional screw press, since the furnace material is only the cylindrical outer cylinder 3', the thickness of the sludge charged into the screw press is approximately the same as the screw shaft 5.
This corresponds to the gap between the outer surface and the outer tube 3' of the cylindrical furnace material, and due to its thick thickness, it is necessary to press and dehydrate in the device for a long time to obtain a dehydrated cake with a constant moisture content. The outer cylinder 3' of the mold furnace material, the screw blades 4', and the screw shaft 5' must be made longer, or the rotation speed of the screw shaft 5' must be reduced because it is necessary to take a long time to compress the material in the device. must be made, and the cylindrical shape is the outer cylinder 1
The disadvantages are that the length of the screw must be very long relative to the diameter of the screw, or that the rotational speed of the screw shaft 5' must be reduced, resulting in a reduction in the amount of solid matter to be treated.

In addition, when the device becomes larger, the gap between the outer surface of the screw shaft 5' and the outer cylinder 3' of the cylindrical material becomes larger, and the longer time is required for dewatering due to the larger size, so the length becomes longer than the diameter. It also has the disadvantage of becoming longer.

In order to improve this shortcoming, the applicant has proposed a clean-up plan (
Patent application No. 54-15241. (See Japanese Patent Application Laid-open No. 109599/1983).

This method will be explained with reference to Fig. 2.The sludge supply port 1
A filtrate outlet 10' and ribs are provided on the cake outlet 6' side in an outer cylinder 3' of a cylindrical furnace material, which is equipped with a hopper 2' at one end and a dehydrated cake outlet 6' at the other end. 7' is fixed, and a screw blade rotating shaft 8' that rotates outside and along the outer surface of the inner cylinder 5'' of the conical cylindrical furnace material is fixed. The rotary screw blades 4' are arranged concentrically, and a driving device 9' for rotating the screw blades is provided.
The rotational force generated is transmitted to the screw blade rotating shaft 8', which is rotatably equipped on the inner cylinder 5'', and the sludge introduced into the screw press type dehydrator is transferred to the rotating screw blade 4'.
The dehydrated cake is fed into the direction of the dehydrated cake discharge port 6' by the rotation of the
The water that oozes out from the filtered and squeezed sludge is transferred to the outer cylinder 3 of the cylindrical furnace material.
' and is discharged from the inner cylinder 5'' of the conical cylindrical furnace material to obtain a dehydrated cake with a low moisture content.

In this case, the sludge supply port 1', the sludge hopper 2' are passed through the outer cylinder 3', which is a cylindrical material, and the inner cylinder 5'', which is a cone-shaped furnace material.
The sludge introduced into the annular gap between the rotary screw blade 4' and the rotary screw blade 4' is sequentially transferred to the dewatered cake discharge port 6' as the rotary screw blade 4' rotates slowly. As the annular gap between the inner cylinder 5'' of the cylindrical furnace material and the rotating screw blade 4' decreases, pressure is gradually applied to the sludge, and the water contained in the sludge flows into the outer cylinder 3' of the cylindrical furnace material and the conical tube. It is discharged from the inner cylinder 5 of the mold furnace material, filtered, compressed and dehydrated, gradually forming a cake shape with a low moisture content, and a dehydrated cake with an extremely low moisture content is obtained from the cake outlet 6'. In this method, a stronger force is applied to the rotary screw blade 4' in order to increase the compression pressure of the dehydrated cake toward the latter half.

For this reason, there is a problem in that the rotating screw blade 4' must be made of a strong material, or a method must be adopted to increase the strength by increasing the thickness toward the rear half.

The object of the present invention is to economically provide a sludge dewatering machine that can effectively eliminate the drawbacks of the conventional screw press.

In this invention, a cone-shaped cylindrical furnace material is installed in the outer cylinder of a cylindrical filter medium having a sludge supply port and a cake discharge port, so that the gap inside the outer cylinder becomes smaller from the sludge supply port to the cake discharge port. In a screw press type dehydrator in which a cylinder is fixedly arranged and a screw blade is rotatably arranged outside the inner cylinder of the conical cylindrical furnace material, the conical cylindrical furnace material is disposed at the radial height of the screw blade. A concentric cylindrical intermediate cylinder is provided in the middle of the interval between the inner cylinder and the outer cylinder of the cylindrical furnace material, and is fixed to the screw blade. The screw blade is rotated on the inner cylinder, and while the sludge is over-squeezed, the water seeping out of the sludge is discharged from the outer cylinder of the cylindrical furnace material and the inner cylinder of the conical cylindrical furnace material to absorb water. This is a screw press type dehydrator that is characterized by producing a dehydrated cake with a low dehydration rate.

An embodiment of the present invention will be described with reference to FIG. 3. A cylindrical shape having a hopper 2 with a sludge supply port 1 at one end and a dewatered cake discharge port 6 at the other end is placed inside an outer cylinder 3 made of material. An inner cylinder 5 of a conical cylindrical furnace material equipped with a filtrate discharge port 10 and ribs 1 on the cake discharge port 6 side is fixed by a support 12 outside the outer cylinder 3, and the inner cylinder of this conical cylindrical furnace material The rotating screw blades 4 are concentrically arranged with a screw blade rotation axis 8 which rotates on the outside of the screw blade 5 and along the outer surface thereof, and the rotational force generated by the drive device 9 for rotating the screw blades is connected to the screw blade rotation axis. 8, the screw blade 4 is rotatably disposed on the inner cylinder 5, and the radial height of the screw blade 4 connects the inner surface of the outer cylinder 3 of the cylindrical furnace material and the inner surface of the conical cylindrical furnace material. A concentric cylindrical intermediate tube 11 is provided fixed to the screw blade 4 at an intermediate portion between the outer surface of the tube 5 (an intermediate position where the space is equally divided into two), and this cylindrical intermediate tube 1
1 is placed at a distance of 1 inch between the sludge supply port 1 and the dewatered cake discharge port 6, either in the first half or in the second half.

The intermediate cylinder 11 is provided to penetrate the screw blade 4 in the axial direction and may be connected to the rotating shaft 8, but the screw blade 4 may be provided separately and protrudingly on the inner and outer peripheral surfaces of the intermediate cylinder 11. The intermediate cylinder 11 may be disposed on the entire surface of the screw blade 4, although at least the intermediate cylinder 11 is not present on the sludge supply port 1 side to facilitate introduction of the sludge into the intermediate cylinder 11. If this is the case, a perforated cylinder or window may be provided in the area of the sludge supply port 1, or
It is effective to use a tube with slits.

Furthermore, the screw blade 4 on the outer periphery of the intermediate cylinder 11 is connected to the rotating shaft 8.
Alternatively, the intermediate cylinder 11 and the screw blades 4 on the inner circumference thereof can be configured to be rotatable integrally.

The sludge put into the screw press type dehydrator is rotated and sent in the direction of the dewatered cake discharge port 6, filtered and squeezed, and the water oozed from the sludge is sent to the outer cylinder 3 of the cylindrical furnace material and the cone-shaped furnace; The material is discharged from the inner cylinder 5 to obtain a dehydrated cake with a low moisture content.

In this case, the sludge introduced into the annular gap between the sludge supply port 1, the sludge hopper 2, the outer cylinder 3 of the cylindrical furnace material, the inner cylinder 5 of the conical cylindrical furnace material, and the rotating screw blades 4 is fed to the rotating screw. As the blades 4 slowly rotate, the sludge is sequentially transferred to the dewatered cake discharge port 6 and is branched into the outer cylinder 3 side of the cylindrical material and the inner cylinder 5 side of the conical cylindrical furnace material. 4, the outer cylinder 3, the inner cylinder 5, and the intermediate cylinder 11 are reduced in annular gap, pressure is gradually applied to the sludge, and the water contained in the sludge is transferred to the outer cylinder 3 of the cylindrical furnace material and the cone-shaped cylindrical furnace material. The cake is discharged from the inner cylinder 5, etc., and subjected to filtration, compression and dehydration, gradually becoming a cake-like cake with a low moisture content, and a dehydrated cake with an extremely low moisture content can be obtained from the cake discharge port 6.

In the latter half of the rotary screw blade 4, the introduced sludge is dehydrated and hardened, and this sludge is further passed through the outer cylinder 3 of cylindrical furnace material, the inner cylinder 5 of conical cylinder furnace material, and the rotary screw blade 4. In order to feed it into the narrowed part of the annular gap formed by
Strong forces must be applied to the sludge by the rotating screw vanes 4.

Since the rotating screw blade 4 is provided with the cylindrical intermediate cylinder 11, even if a strong force is applied to the rear half, the high part of the rotating screw blade 4 in the front half, that is, the strong part, and the cylindrical intermediate cylinder 11 By being fixed and integrated, it has become stronger, and the second
The rotary screw blade 4' shown in the illustrated example can withstand stronger forces.

In other words, a strong force can be applied to the sludge in the device, especially in the rear half of the rotary screw blade 4, and even if the squeezing pressure becomes high and the force applied to the rotary screw blade 4 becomes strong, the sludge can be applied to the sludge in the cylindrical intermediate cylinder 11. Since the strength of the sludge is strengthened by the sludge, the sludge can be compressed and dehydrated to produce a dehydrated cake with a low water content.

The present invention has an inner cylinder of a conical cylindrical furnace material inside an outer cylinder of a cylindrical furnace material having a sludge supply port and a cake discharge port, and a screw that can freely rotate concentrically along the outer surface of the inner cylinder. A conical cylindrical furnace is provided with a blade, and an intermediate cylinder is provided at the radial height of the screw blade, and an intermediate cylinder is provided in the middle of the interval between the inner surface of the outer cylinder of the cylindrical material and the outer surface of the inner cylinder of the conical cylindrical furnace material. The gap between the inner cylinder of the material and the inner surface of the outer cylinder is made smaller in the direction of the discharge port, the sludge is squeezed by the rotation of the screw blades, and the water that oozes out from the sludge is transferred to the outer cylinder of the cylindrical furnace material and the conical cylindrical furnace. While dehydrating the material by discharging it from the inner cylinder, a dehydrated cake with a low moisture content can be generated from the cake outlet. By providing a cylindrical intermediate tube fixed to the rotating screw blade in the middle of the interval, the strength of the rotating screw blade is increased and the sludge squeezing pressure can be further increased, compared to the conventional screw press type dewatering. This method has the practical effect of being able to rationally eliminate and resolve the drawbacks of the dehydrator, as well as significantly lowering the moisture content of the dehydrated cake compared to conventional screw press type dehydrators.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional view of a conventional example, FIG. 2 is a longitudinal sectional view of an improved type, and FIG. 3 is a longitudinal sectional view of an embodiment of the present invention. DESCRIPTION OF SYMBOLS 1...Sludge supply port, 2...Hopper, 3...Outer cylinder of cylindrical furnace material, 4...Rotating screw blade, 5...
Inner cylinder of conical cylindrical furnace material, 6... Dehydrated cake outlet, 7.
... Rib, 8 ... Screw blade rotation shaft, 9 ... Drive device for screw blade rotation, 10 ... Filtrate discharge port, 11 ... Cylindrical intermediate tube, 12 ... Cone-shaped Support for the inner cylinder of cylindrical furnace material.

Claims (1)

[Scope of Claim for Utility Model Registration] 1. Inside the outer cylinder of a cylindrical furnace material having a sludge supply port and a cake discharge port, a conical shape is provided so that the gap in the outer cylinder becomes smaller from the sludge supply port to the cake discharge port. In a screw press type dehydrator in which an inner cylinder of a cylindrical furnace material is fixedly arranged and a screw blade is rotatably arranged outside the inner cylinder of the conical cylindrical furnace material, at least the sludge supply port is provided in the screw blade. A screw press type dehydrator with an intermediate cylinder fixed in the axial direction so as to cover the inner cylinder except for the sides. 2. The dehydrator according to claim 1, wherein the intermediate cylinder equally divides a space between an outer cylinder and an inner cylinder in which the screw blades are disposed. 3. The dehydrator according to claim 1 or 2, wherein the intermediate cylinder is provided to penetrate the screw blade in the axial direction and is connected to a rotating shaft. 4. Utility model registration claims 1, 2, or 4, wherein the inner cylinder is connected to a rib forming a filtrate discharge port, and is fixedly provided with a support outside the outer cylinder. The dehydrating hair bowl 5 according to claim 3, wherein the intermediate cylinder is attached to the entire surface of the screw blade, and at least on the sludge supply port side is a perforated cylinder. The dehydrator according to item 3 or 4.