JPH07204895A - Spacing adjusting device of outside cylinder of screw press and screw shaft - Google Patents

Abstract

PURPOSE:To enable efficient sepn. of solid from liquid by making either of a screen outside cylinder and a screw shaft freely adjustable in movement in its axial line direction with respect to the other. CONSTITUTION:The screen outside cylinder 1 is composed to a circular conical shape formed to a diameter increasing toward the other end from the base end. The screw shaft 2 is concentrically supported therein. Both 1, 2 are so formed that the spacing therebetween is made narrower from the beginning end toward the terminal. Screw vanes 3 in proximity to the inside surface of the screen outside cylinder 1 are wound around the outside peripheral surface of the screw shaft 2 and a series of scrapers 3a which are capable of making sliding contact with the inside surface of the screen outside cylindrical 1 are mounted at the outer peripheral edges of these screw vanes 3. Further, either one of the screen outside cylinder 1 and the screw 2 is made freely adjustable in movement in the axial line direction with respect to the other. As a result, a spacing is easily correctable even if this spacing generates in the clearance between a feed shaft and the screen outside cylinder during running.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of a screw press used for dewatering sewage sludge and the like, and using it for sludge having a low concentration of fibers and a low concentration, it is possible to perform an efficient dewatering work in which a screen outer cylinder is unlikely to be clogged. It is intended to provide a device capable of doing so.

[0002]

2. Description of the Related Art Conventionally, a screw press dehydrates a slurry containing a large amount of fibrous material and having a high concentration by pressing strongly with a screw, and is not suitable for dewatering a slurry having a low fibrous material and a thin concentration. Recently, coagulants have been developed and are used for dehydration of such a slurry having a low concentration.

[0003]

However, when a slurry having a low concentration of fibers and a thin concentration is aggregated with a polymer coagulant, a film having a high viscosity due to the polymer coagulant is formed between the inner surface of the screen outer cylinder and the screw blade. There is a problem that the screen is clogged. The problem of this clogging is that the slurry having a relatively large amount of fibrous material can be removed by washing the film of the polymer coagulant containing the fibrous material with the fibrous material. It cannot be removed.

[0004]

SUMMARY OF THE INVENTION The present invention is suitable for a slurry having a small amount of fibrous material agglomerated by the above-mentioned polymer coagulant and does not cause clogging, and is also outside the screen. The present invention embodies a device that can easily cope with wear of a cylinder and screw blades and can perform an efficient dehydration work.

That is, the gist of the present invention is that the screw shaft is supported concentrically in the screen outer cylinder, and the distance between the inner peripheral surface of the screen outer cylinder and the outer peripheral surface of the screw shaft is from the start end to the end. In a screw press configured to become narrower as it reaches the outer peripheral surface of the screw shaft, the outer peripheral edge of the screw blade is wound close to the inner surface of the screen outer cylinder, the outer peripheral edge portion of the screw blade. A series of scrapers capable of sliding contact with the inner surface of the screen outer cylinder are mounted, and further, either one of the screen outer cylinder and the screw shaft can be moved and adjusted in the axial direction with respect to the other. .

[0006]

The apparatus according to the present invention is configured as described above, and the undiluted solution supplied to the screen outer cylinder is sent toward the outlet by the screw blades as the screw shaft rotates, and is then discharged from the screen. Pressure is applied due to the narrowing of the distance between the cylinder and the screw shaft, the filtrate falls from the screen, and the cake is taken out from the outlet at the other end.

In the conventional apparatus during the dehydration work as described above, when the concentration of the stock solution is low, the solid matter clogging the screen and the dehydration is poor and the screw blades send the stock solution in a fluidized state. Dehydration efficiency is poor because pressure is not applied. On the other hand, when a flocculant such as a polymer flocculant is added to the stock solution having such a low concentration to increase the flocs, the flocs form a layer on the inner surface of the screen to form a film, which impairs the dehydration property. This membrane can be washed away with the fibrous material by washing if the fibrous material in the stock solution is long, but cannot be removed if the fibrous material is short.

In the apparatus according to the present invention, even if the concentration of the stock solution is low and the fibers are short, the screen can be prevented from being clogged, and the dehydration work can be performed efficiently. That is, in the device according to the present invention, since the scraper is attached to the outer peripheral edge portion of the screw blade so that the outer peripheral edge portion is close to the inner surface of the screen inner cylinder, the scraper scrapes the flock film to be laminated. Clogging can be prevented. And
Since this scraper is installed over the entire length up to the outlet of the screw blade, even if the stock solution has a low concentration, it is possible to prevent clogging of the screen up to the outlet and perform efficient dehydration work. it can.

Further, since this scraper is constructed separately from the screw blades fixed to the feed shaft, its peripheral line can be easily provided close to the inner surface of the screen outer cylinder and can be easily replaced. If so, the feed shaft does not need to be manufactured with high precision and can be manufactured at low cost.

Further, according to the present invention, since the screen outer cylinder and the screw shaft can be relatively moved and adjusted in the axial direction thereof, when the scraper wears and the clearance between the screen outer cylinder and the inner surface becomes large. Further, by moving either one of the screen outer cylinder and the screw shaft, the clearance between them can be reduced. On the contrary, it is needless to say that the clearance can be increased, and this movement adjusting device facilitates the work both in manufacturing and assembling the screen outer cylinder and the feed shaft. Below, based on the drawings
The present invention will be specifically described.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In FIG. 1, reference numeral 1 is a screen outer tube, 2
Is a screw shaft, and 3 is a screw blade. The screen outer cylinder 1 has a conical shape whose diameter increases from the base end (right side in the figure) to the other end, and the screw shaft 2 supported inside the screen outer cylinder 1 also extends from the base end to the other end. The diameter is made larger as it reaches, and the gap with the screen outer cylinder 1 is narrowed. The outer peripheral edge of the screw blade 3 wound around the screw shaft 2 is located close to the inner surface of the screen outer cylinder 1.

Next, reference numeral 3a is a scraper fixed to the outer peripheral edge portion of the screw blade 3, which is made of an elastic material such as rubber and which extends from the base end of the screw blade 3 to the other end thereof. An object is attached, and its outer peripheral edge portion is in sliding contact with the inner surface of the screen outer cylinder 1. Further, the screw shaft 2 is supported on the mounts 4 and 4 so as to be movable in the axial direction. Reference numeral 5 is a jack for adjusting the movement thereof, and 6 is a bush of the sliding portion.

Reference numeral 7 is a mixing tank to which a flocculant is added, 8
Is a stirrer, 9 is a supply port for the undiluted solution, and 10 is an adjustment gold provided at the exit of the cake, and the drive device of the screw shaft 2 is omitted.

The apparatus according to the present invention is constructed as described above, and the stock solution to which the coagulant is added in the mixing tank 7 is supplied from the supply port 9 into the screen outer cylinder 1 and the screw shaft 2
With the rotation of the screw blade 3, it is sent to the left in the figure and pressure-filtered by the screw blades 3, the filtrate is below the screen outer cylinder 1, and the cake is out of the machine from the left end of the screen outer cylinder 1. Taken out.

When this stock solution is solid-liquid separated in the screen outer cylinder 1, in the present invention, a series of scrapers 3a from the feed start end to the end are provided on the outer peripheral edge of the screw blade 3a. Since it is slidably contacted with the inner peripheral surface of the screen outer cylinder 1, the slurry film of the undiluted liquid that has been added with the coagulant is deposited and adhered on the inner surface of the screen outer cylinder 1 to prevent clogging of the screen. Can be prevented.

That is, in the conventional screw press,
The inner surface of the screen outer cylinder 1 cannot be sufficiently approached due to processing precision in manufacturing the screw blades 3 and the like, and therefore, the agglomerated slurry does not enter the clearance between the inner surface of the screen outer cylinder 1 and the outer peripheral edge of the screw blades 3. Although a film is formed, according to the present invention, the scraper 3a can be separated from the screw blade 3 and brought into sliding contact with the inner surface of the screen outer cylinder 1, so that the slurry film can be completely prevented. It is a thing.

Since the scraper 3a is a series of from the start end to the end of the screw blade 3, even if it is a stock solution having a low concentration and having fluidity, a solid-liquid separation action is performed up to the end of the screen outer cylinder 1. It is possible to perform efficient dehydration, and since it is a separate body from the screw blade 3, it can be easily replaced if it is worn out.

Further, the screen outer cylinder 1 of the scraper 3a and the screen outer cylinder 1 of the apparatus according to the present invention is formed in a conical shape, and the scraper 3a is formed on the conical surface.
Are in sliding contact with each other, and both of them can be moved and adjusted in the axial direction. Therefore, when the scraper 3a is worn or the like, a slurry film is deposited on the inner surface of the screen by moving one of them. Can be prevented. In the case of the illustrated example, the scraper 3a can be brought closer to the screen outer cylinder 1 by moving the screw shaft 2 to the right with the jack 5.

[0019]

As described above, according to the apparatus according to the present invention, even the stock solution of a small concentration with a small amount of fibrous substances coagulated by a polymer coagulant or the like can cause clogging of the screen outer cylinder. At the same time, the raw solution is conveyed to the end of the feed blade while the solid-liquid separation is carried out, enabling highly efficient solid-liquid separation,
Furthermore, even when manufacturing the feed blade, even if there is a gap in the clearance between the feed shaft and the screen outer cylinder during operation, this can be easily corrected, and it will have a great effect in using the screw press. is there.

[Brief description of drawings]

FIG. 1 is a schematic side view of a device according to the present invention, showing an incision of essential parts.

FIG. 2 is an enlarged vertical sectional view of a main part of the present invention.

[Explanation of symbols]

 1 Screen outer cylinder 2 Screw shaft 3 Screw blade 3a Scraper

Claims (1)

[Claims] 1. A screw shaft (2) is supported coaxially inside a screen outer cylinder (1), and the distance between the inner peripheral surface of the screen outer cylinder (1) and the outer peripheral surface of the screw shaft (2) becomes narrower from the start end to the end end. In the screw press configured so as to reduce the number of screw blades, the screw blade 3 whose outer peripheral edge is close to the inner surface of the screen outer cylinder 1 is wound around the outer peripheral surface of the screw shaft 2, and the outer peripheral edge portion of the screw blade 3 has the above-mentioned outer peripheral portion. A series of scrapers 3a capable of sliding contact with the inner surface of the screen outer cylinder 1 are attached, and further, either one of the screen outer cylinder 1 and the screw shaft 2 is movable and adjustable in the axial direction with respect to the other. The gap adjusting device between the outer cylinder and the screw shaft in the screw press.