JPH11309312A - Multiple-plate type screw press filter apparatus for raw water in low concentration - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance the receiving efficiency of treated raw water of a low concn. by a multiple plate type screw press filter apparatus. SOLUTION: A filter cylinder 2 wherein a large number of annular fixed plates 11 and a large number of annular movable plates 12 are alternately arranged in a superposed state so as to provide fine filtering gaps between the plates 11, 12 is arranged between an inlet chamber 1 for receiving treated raw water and an outlet chamber 3 for discharging a treated cake, and a main screw 5a starting from the interior of the inlet chamber 1 to pierce the filter cylinder 2 over the total length thereof is arranged and the mechanism 14 shaking the movable plates 12 is provided and auxiliary screws 5b are provided at least between the main screw pitches within the inlet chamber 1 to form a screw press filter.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a screw press filtration device for filtering low-concentration raw water containing sludge and other suspended matter to separate the filtrate into a filtrate and a dewatered cake.

[0002]

2. Description of the Related Art A conventional screw press filtration apparatus is disclosed in, for example, Japanese Patent Publication No. 63-65364 (Patent No. 1520).
No. 106) There is a screw-through filter tube installation system as described in the gazette. In this type of filtration device, a filtration tube for filtering raw water from the inside of the drum to the outside in a radial direction is installed in a substantial range excluding both end portions in the drum, and a drum peripheral surface in the substantial range is provided. A large number of through-holes are provided, and furthermore, a screw penetrating through the filter tube is arranged over the entire length of the drum, so that both ends in the drum are used as an inlet chamber for treated raw water and an outlet chamber for a dewatered cake. It was done. The filtration passage in the filter tube is formed by a minute gap between the plates in an alternate arrangement of the annular fixed plate and the annular movable plate that constitute the tube.

[0003] In the above structure, the screw introduces the raw water into the filtration tube in cooperation with the inflow of the raw water supply pump into the inlet chamber or the overflow from the pretreatment section such as the coagulation stirrer tank. If the concentration of the raw water is too low, the raw water is introduced into the filter tube from the inlet chamber and idles in the raw water that stagnates or moves only slowly depending on the flow path resistance on the outlet side. Will be. Therefore, if the screw pitch is made smaller, the screw blade area through the entire length of the filter tube becomes larger, and the treated raw water can be more strongly propelled. However, in this case, there arises a disadvantage that the treated raw water is brought to the outlet chamber with insufficient dehydration.

[0004]

SUMMARY OF THE INVENTION It is an object of the present invention to increase the thrust of the screw from the inlet chamber into the filter cylinder to properly introduce the raw water to be treated, and to reduce the thrust to a normal level in the filter cylinder. It is an object of the present invention to provide a multi-plate screw press filtration device having a screw structure in which raw water is allowed to pass through the inside of a filtration tube by taking a time suitable for dehydration by lowering.

[0005]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention comprises: a) a plurality of annular fixing plates and an opening having a diameter slightly larger than the opening diameter of the fixing plate. It consists of a number of annular movable plates capable of swinging in the same plane at the same amplitude, and alternately overlapping arrangements each having a small filtration gap, and a fixed cylindrical space is defined by the row of openings of the fixed plate. The formed filtration tube,
Installed between an inlet chamber for receiving treated raw water and an outlet chamber for discharging treated cake; b) arranging a main screw starting from the inlet chamber and penetrating the entire length of the cylindrical space of the filter tube; By providing a mechanism for swinging the movable plate by the rotation of the main screw, the raw water received in the filter tube from the inlet chamber is pressed and propelled toward the outlet chamber, and the movable plate swings. (C) an auxiliary screw is provided at least between the main screw pitches in the inlet chamber.

[0006] According to the above configuration, the double screw structure of the main screw and the auxiliary screw in the inlet chamber can be used even if the concentration of the raw water introduced into the chamber is low.
Since the contact area with the raw water is doubled, a function of propelling into the filter cylinder is exhibited without idling. The propulsive force per unit length received by the treated raw water entering the filter cylinder is halved from the position where only the main screw was used, so the treated raw water passes through the filter cylinder taking the time required for dewatering from the filtration gap. Will do.

In order to obtain a sufficient effect of introducing the treated raw water from the inlet chamber into the filter cylinder, the length of the auxiliary screw should be set so that the rear end of the auxiliary screw is slightly located in the filter cylinder. Should be set.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a screw press type filtration apparatus according to a preferred embodiment of the present invention will be described with reference to the drawings.

In the embodiment of the screw press filtration apparatus of the present invention, as shown in FIG. 1, an inlet chamber 1, a filter cylinder 2 and an outlet chamber 3 are provided continuously from the right, and a cylindrical space 4 in the filter cylinder 2 is provided. ,
A main screw 5a supported by a shaft 5 extending from the inlet chamber 1 to the outlet chamber 3 over the entire length of the present filtration device penetrates. An inlet hole 1a for receiving raw water to be treated is formed in an upper part of the inlet chamber 1, and an outlet hole 3a is formed in a lower part of the outlet chamber 3.
a is formed. In the inlet chamber 1 and slightly behind the inlet end of the filter tube 2 (for example, at a position about 0.1 to 0.2 times the total length).
Between the pitches of the main screw 5a, the auxiliary screw 5b is separately installed at the same pitch on the same screw shaft 5.

The front end plate 6a and the rear end plate 6b of the filter cylinder 2
A rear end tube 7 which forms a boundary between the inlet chamber 1 and the outlet chamber 3 and extends from the aligned opening of the rear end plate 6b and forms an extension of the inner wall of the filter tube is protruded, and the screw shaft 5 is thinned. A valve board 8 for controlling the discharge of the processing object is fitted to the rear end shaft portion 5 '. The rear face of the valve disc 8 is supported by a spring 9 mounted on the rear end shaft portion 5 'at the rear thereof. The end of the end tube 7 and the rear end of the screw shaft 5 (the root of the shaft portion 5 ') are in contact with each other to close the outlet of the filter tube 2.

The filter cylinder 2 has a number of annular fixed plates 11, which are fixed between, for example, four support rods 10 (FIG. 2) and the like, and is provided between the front end plate 6a and the rear end plate 6b. A plurality of annular movable plates 12 having a center opening diameter slightly larger than the center opening diameter, and an alternating superimposed arrangement in which fine filtration gaps are provided.
Can swing in the same plane at an amplitude corresponding to the difference in diameter from the fixed plate 11 by a cam mechanism described later.
In this case, the above-described cylindrical space 4 is defined by the row of openings of all the fixed plates 11, and the movable plate 12 does not narrow the inner peripheral surface of the cylindrical space 4 due to its swing. Therefore, the outer edges of the screws 5a and 5b are fitted to this inner peripheral surface, and can rotate continuously.

Both ends of the screw shafts 5, 5 'are supported by bearings installed on the outer end plates 13a and 13b of the inlet chamber 1 and the outlet chamber 3, and protrude from the bearings of the outlet chamber outer end plate 13b. The rear end is driven to rotate via gears and the like, and is linked to another rotating shaft 15 by a gear train 14. As is apparent with reference to FIG. 2, the rotating shaft 15 also extends between the outer end plates 13a and 13b in the lower part of the filtration device, and reduces the diameter of the filter cylinder 2 within the range, and reduces the diameter of the small diameter portion 15 Has a cam key 16 extending in the axial direction on the peripheral surface of '.

The fixed plate 11 is a complete annular plate having an outer periphery forming the outer peripheral surface of the filter tube 2 and an opening for defining the cylindrical space 4 described above, and penetrates and supports the four support rods 10. Each of the plates 11 is maintained at a mutual interval by a spacer 17 made of a small disk that is also penetrated and supported by the support rod 10. On the other hand, the movable plate 12 has a concave portion 18 surrounding the spacer 17 with a margin, an outer periphery slightly smaller than the fixed plate 11, and an opening 19 having a diameter slightly larger than the opening (the cylindrical space 4) of the fixed plate 11. An upper hole 20a and a lower hole 20b are respectively formed in upper and lower portions thereof, and a fulcrum rod 2 is formed in the upper hole 20a.
1 is loosely fitted, and the above-described intermediate small diameter portion 15 'of the rotating shaft 15 is fitted into the lower hole 20b. Small diameter part 1
As is clear from FIG. 1, the lower hole of each fixing plate 11 through which 5 ′ penetrates corresponds to the circular locus of the cam key 16 or has a diameter larger than that of the cam key 16 so that the small diameter portion 15 ′, Therefore, although the rotation of the rotating shaft 15 is permitted, the above-described lower hole 20b of each movable plate 12 has only a diameter slightly larger than the size obtained by adding the projection size of the cam key 16 to the main body diameter of the small diameter portion 15 '. As the cam key 16 rotates, it is driven by a cam to rotate eccentrically, and the movable plate 12 itself mainly swings up and down with a fulcrum rod 21 penetrating through the upper hole 20a as a fulcrum.

Next, as apparent from FIG. 3, which is a partial cross-sectional view taken along the line II-II of FIG. 2 and enlarged, as shown in FIG. , 11, in this case having a thickness slightly greater than the thickness of the movable plate 12, to form a small filtration gap between the plates 10, 11,
Thus, a filter tube 2 (FIG. 1) composed of an array of a number of plates 11 and 12 is completed.

In the structure of the first embodiment described above, when the screw shaft 5 is driven, the rotating shaft 15 is simultaneously rotated by the gear train 14 and the cam key 16 is rotated, so that the movable plate 12 is rotated as described above. Lower hole 20b
(See FIG. 2). The movable plate 12 swings eccentrically within the range in which the upper hole 20a can play around the fulcrum rod 21. In this case, the height of the cam key 16 is set equal to the inner diameter difference between the fixed plate 11 and the movable plate 12, and the difference between the inner diameter of the small hole 20a and the diameter of the fulcrum rod 21 is set substantially equal to this. 2, the upper edge of the opening 19 of the plate 12 coincides with the opening of the fixed plate 11, that is, the upper end of the inner peripheral surface of the filter cylinder 2 in the lowermost state shown in FIG. The edge coincides with the opening of the fixed plate 10, that is, the lower end of the inner peripheral surface of the filter cylinder 2, and does not enter the inside of the inner peripheral surface 4 of the filter cylinder during one rotation of the rotating shaft 15.

The low-concentration raw water introduced from the inlet 1a is propelled by the screws 5a and 5b in the inlet chamber 1, and is supplied into the filter tube 2 without stagnation. In the filter tube 2 (with the help of the auxiliary screw 5b at the entrance), the treated raw water that has received the propulsion force reduced by half per unit volume by the main screw 5a is gradually squeezed, and the above-described movable plate The water is radiated through the filtration gap that is constantly (slidably) regenerated between the plates 11 and 12 by the rocking of the water 12, and the water is radially dehydrated from the outer periphery. As a result, the cake having a sufficiently low water content can be discharged from the outlet hole 3a.

[0017]

As described above, according to the present invention, the screw penetrating the multi-plate filter tube has a double structure at the inlet, so that low-concentration raw water can be efficiently introduced into the filter tube and filtered. In the cylinder, the propulsive force per unit volume is reduced by half with a single screw, and after sufficient dehydration,
The processed cake can be discharged.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing an embodiment of a multi-plate screw press filtration device for low-concentration raw water of the present invention.

FIG. 2 is a sectional view taken on line II of FIG. 1;

FIG. 3 is a partial sectional view taken along the line II-II of FIG. 2;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Inlet room 2 Filter tube 3 Outlet room 4 Cylindrical space 5 Screw shaft 5a Main screw 5b Auxiliary screw 6a, 6b Filter tube both end plates 7 Rear end plate 8 Valve board 8b Exit indoor end plate 9 Spring 10 Support rod 11 Fixing plate 12 Movable plates 13a, 13b Outer end plate 14 Gear train 15 Rotating shaft 16 Cam key 17 Spacer 18 Depression 19 Opening of movable plate 20a Upper hole 20b Lower hole 21 Support rod

──────────────────────────────────────────────────続 き Continued on front page (51) Int.Cl. ⁶ Identification code FI B30B 9/14

Claims (2)

[Claims] A) a plurality of annular fixed plates, and a plurality of annular plates having an opening diameter slightly larger than the opening diameter of the fixed plate and capable of swinging in the same plane at an amplitude corresponding to the difference in the opening diameters. With a movable plate, a filtration tube, which consists of an alternately superimposed array with each minute filtration gap, and defines a fixed cylindrical space by the row of openings of the fixed plate,
Installed between an inlet chamber for receiving treated raw water and an outlet chamber for discharging treated cake; b) arranging a main screw starting from the inlet chamber and penetrating the entire length of the cylindrical space of the filter tube; By providing a mechanism for swinging the movable plate by the rotation of the main screw, the raw water received in the filter tube from the inlet chamber is pressed and propelled toward the outlet chamber, and the movable plate swings. A screw press filtration device which constantly regenerates the filtration gap between each plate by: c) an auxiliary screw provided at least between main screw pitches in the inlet chamber. . 2. The filter according to claim 1, wherein the auxiliary screw extends to a position immediately after an inlet end of the filter tube.