JP2000246495A - Screw press with separately driven moving plate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To constitute a multiple plate type screw press in which the oscillation speed of a movable plate is made different at the front half part and rear half part of a filtering cylinder. SOLUTION: In a filtering cylinder 2 is constituted of an alternately superposed array of a number of annular fixed plates 11 and a number of annular movable plates 12 with a spacing of minute filtering gaps, a first drive mechanism 13 to drive the screw 5 rotatively, further second drive mechanism 14a, 15a and third drive mechanisms 14b, 15b to drive the movable plates of each part, respectively, are arranged.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention can be used for a multi-plate screw press filtration device for filtering treated raw water containing sludge and other suspended matter and separating it into a filtrate and a dewatered cake, or for concentrating fruit juice. The present invention relates to an improvement of a multi-plate screw press concentrator.

[0002]

2. Description of the Related Art As a conventional multi-plate screw press filtration apparatus, there is a screw-through filter cylinder installation system as described in, for example, Japanese Patent Publication No. 63-36464 (Patent No. 1520106). 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 clearance in the filter tube is formed by minute gaps between the plates in an alternating arrangement of a number of annular fixed plates and a number of annular movable plates constituting the tube. In recent years, a device is often used without forming a drum portion surrounding the filter tube portion.

In the configuration of the above-mentioned conventional filtering apparatus, all the annular movable plates are synchronously swung by the same drive shaft in the same movement pattern in each arrangement plane.
Therefore, at the inlet side or the first half of the filter tube having a high water content in the phase to be treated, the swinging speed is increased by increasing the rotation speed of the movable plate drive shaft, thereby reliably preventing clogging of the filtration clearance, The processing amount, that is, the amount of water squeezing / filtration can be increased.

As described above, a high swinging speed of the movable plate is preferable for the first half of the filter tube, but at the outlet side or the second half of the filter tube, the phase to be treated has a sufficiently low water content. In spite of the difficulty of further dehydration under the same conditions in a cake-like state, the filtration clearance that fluctuates at a high speed draws in the cake-like phase and kneads it around the periphery. As a result, the recovery of the concentrated phase deteriorates and its water content does not decrease.

[0005]

In order to eliminate the above-mentioned inconveniences, the present invention separately drives the drive shafts of the movable plates in the first half and the second half of the filter tube, so that both can be adjusted according to the sludge concentration. It is an object of the present invention to provide a multi-plate screw press filtration device which is driven at an optimum rocking speed, drains water well, and has an excellent recovery rate of a concentrated phase.

[0006]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a filter tube comprising a number of annular fixed plates and a number of annular movable plates, which are arranged in an alternately superimposed arrangement with respective fine filtration gaps. Wherein a screw that penetrates the entire length of the filter tube is disposed, and wherein a first drive mechanism that rotationally drives the screw and the movable plate swing at different speeds in the first half and the second half of the filter tube. A screw press device comprising a second drive mechanism and a third drive mechanism for driving a movable plate for each part so as to move.

According to the above construction, in the first half of the filter tube in which the water content of the phase to be treated is high, the movable plate is swung at a high speed corresponding to the large amount of water squeezed in this range. Moisture is discharged without clogging of the filtration clearance, and the movable plate is swung at a relatively low speed in the latter half of the filtration tube where the water content of the phase to be treated is small and the viscosity and concentration are high, so that the flow of the filtration clearance is reduced. The purpose is to increase the channel resistance and overcome this high channel resistance to discharge only the water that is squeezed.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment of the present invention will be described below with reference to the accompanying drawings.

The first aspect of the screw press filtration device of the present invention
As shown in FIG. 1, an inlet chamber 1, a filter tube 2, and an outlet chamber 3 are provided in series from the right, and a screw 5 is formed in a cylindrical space defined on an inner peripheral surface 4 of the filter tube 2. The screw blade of the screw shaft 5 extends from the inlet chamber 1 to the outlet end of the filter tube 2 over almost the entire length of the present filtration device.
a. The filter cylinder 2 has a structure in which a front half 2a connected to the inlet chamber 1 and a rear half 2b connected to the outlet chamber 3 are abutted with an intermediate plate 2c interposed therebetween, and the screw structure has a pitch between the screws 5 in the rear half 2b. Second
The screw blade 5 'is added.

An inlet hole 1a for receiving raw water to be treated is formed in an upper portion of the inlet chamber 1, and an outlet hole 3a is formed in a lower portion of the outlet chamber 3. The screw shaft 5a is
A main tip edge 5b corresponding to the end of the screw blades 5, 5 'ending in the extension cylinder portion 2d having the same opening diameter of the filtration cylinder 2,
From this, a small diameter tip shaft 5c is formed. The tip shaft 5c is supported by bearings on the outer end plate 3b of the outlet chamber 3. An outlet valve 6 having a substantially trapezoidal longitudinal section is provided at the tip shaft 5c.
Are movably fitted and supported in the axial direction, and a coil spring 7 is mounted at the rear thereof. The valve 6 is pressed forward by a coil spring 7 and occupies an outlet closed position where the center of the front end of the valve 6 abuts and is restricted by the main front edge 5b at the time of stopping the apparatus and starting the apparatus.

The protruding tip of the extension tube portion 2d of the filter tube 2 is pressed and sealed at its entire edge by the conical slope of the valve 6 at the time of the above-mentioned stop of the apparatus and at the time of start-up, thereby establishing the outlet closed state. The valve 6 in the closed position is pushed back backward due to a rise in the pressure of the treated raw water that comes into contact with the portion other than the center of the front end after the operation of the apparatus, and opens the filter cylinder 2. The filter cylinder 2 has a rear end plate 8 at an outlet side, that is, an outer end on the rear half 2b side, and a front end plate 9 at an inlet side, that is, an outer end on the front half part 2a side.
The internal structure of the front half part 2a and the rear half part 2b are substantially the same. For example, four rows of support bars 10 (FIGS. 2 and 3) are provided between the front and rear end plates 8, 9 and the intermediate plate 2c. A plurality of annular fixed plates 11 are fitted and supported at intervals on the support rods 10, and one annular movable plate 12 is arranged in each of the intervals to form an alternate plate arrangement. , A minute gap, that is, a filtration clearance is formed between each fixed plate / movable plate. 2 and 3 are views of the first half portion 2a of the filter tube, and similar views of the second half portion 2b are omitted, but this may be reminiscent of a structure to which a second screw blade 5 'is added.

The movable plate 12 has a center opening diameter slightly larger than the center opening diameter of the fixed plate 11, and can be swung in the same plane with an amplitude corresponding to the difference in diameter from the fixed plate 11 by a cam mechanism described later. It has become. That is, the row of openings of all the fixed plates 11 defines the inner peripheral surface 4 of the above-described cylindrical space, and the opening edge of the movable plate 12 is dimensioned so that the inner peripheral surface 4 is not narrowed by the swing. Have been. Therefore, the outer edges of the screws 5, 5 'are fitted to the inner peripheral surface 4 and can rotate continuously.

Referring again to FIG. 1, the outer ends of the screw shafts 5a and 5c are supported by bearings installed on the outer end plates 1b and 3b of the inlet chamber 1 and the outlet chamber 3, respectively. The outer end of the tip shaft 5c protruding from the bearing 3b fixedly supports the output pulley 13a of the belt / pulley transmission system 13 constituting the first drive mechanism, and the input pulley 13b.
Is driven by a motor M1 supporting the.
At the level near the lower end of the filter tube 2, the outer end plate 1 of the inlet chamber
b to the intermediate plate 2c of the filter tube 2 and from the outer end plate 3b of the outlet chamber to the intermediate plate 2c of the filter tube 2,
Thin rotating shafts 14a and 14b extending through the first and the second 12, respectively, are arranged. The rotating shafts 14a and 14b are supported by bearings on the outer end plates 1b and 3b, and the output shaft pulleys of the belt / pulley transmission systems 15a and 15b as second and third driving mechanisms are provided on the outer shaft ends. And a motor M2 that supports each input side pulley
a and M2b are individually driven to rotate.

Each of the rotating shafts 14a and 14b has a cam key 16 which protrudes in a radial direction in a range where the plates 11 and 12 penetrate. As is clear from FIG.
2 has a U-shaped notch 17 surrounding each support rod 10 with a margin, and each of two fixed plates 11 opposed to each other with the movable plate 12 interposed therebetween has a support rod 10 inside the notch 17.
The opposing surface is supported by the spacer 18 fitted and supported by the support member 10, and the supporting rod 10 itself is fitted and supported by the support rod 10 penetrating the rod hole 22 at the center of the opposing surface to maintain the mutual interval. .

The fixed plate 11 has a circular outer periphery or a non-circular (not shown, for example, substantially triangular) outer edge contour forming the outer peripheral surface of the filter cylinder 2 and a circular or substantially circular shape defining the inner peripheral surface 4 described above. The opening plate may have any openings.
In this embodiment, the movable plate 12 is an annular plate having an outer periphery slightly smaller than the circular fixed plate 11 and a similar opening 19 having a diameter slightly larger than the opening (the inner peripheral surface 4) of the fixed plate 11, and upper and lower portions thereof. An upper hole 20a and a lower hole 20b are formed in the upper hole 20a, and a fulcrum rod 21 is loosely fitted in the upper hole 20a.
4a and 14b are fitted.

As is apparent from FIG. 1, the lower hole of each fixed plate 11 through which the rotating shafts 14a and 14b pass has a diameter large enough to allow the circular locus of the cam key 16 so that the rotating shafts 14a and 14b can be fixed in the fixed state. Is allowed, but the diameter of the lower hole 20b of each movable plate 12 is slightly larger than the sum of the diameter of the main body of the rotating shafts 14a and 14b and the size of the protrusion of the cam key 16. Therefore, the cam plate 16 is driven eccentrically by the rotation of the cam key 16 to rotate eccentrically, and swings the movable plate 12 up, down, left and right with the fulcrum rod 21 penetrating the upper hole 20a as a fulcrum.

FIG. 3 is a partial sectional view taken along the line BB of FIG. As apparent from FIG. 3, the spacer 18 in the notch 17 maintains the distance between the two fixed plates 11, 11 at a distance slightly larger than the thickness of the movable plate 12. Plate 11,
A filtration clearance g of a minute gap is formed between the two.

According to the structure of the first embodiment described above, the screw rotates at a rotation speed set according to the concentration of sludge to be treated (for example, a relatively high rotation speed if the concentration is high). M1 is driven via the first transmission system 13. On the other hand, the movable plate 12 is driven by the motor M2a in the first half 2a in response to the decrease in the water content of the phase to be treated in accordance with the entry position in the filter tube.
It is driven to swing at a sufficient speed via a,
The second half 2b is driven by the motor M2b via the transmission system 15b so as to swing at a lower speed than the swing speed of the first half 2a. Therefore, the filtration clearance g between the plates 11 and 12 is always effectively regenerated without clogging due to the sufficiently fast swing of the movable plate in the first half 2a.
In the latter half 2b, the flow path resistance is increased by the swing of the movable plate whose speed has been reduced.
Only the squeezed water from the phase to be treated, strongly squeezed by the 5 ′ structure, is substantially received and passed.

FIG. 4 is a side view showing a second embodiment of the present invention, and the portions denoted by the same reference numerals as those of FIG. 1 have the same structure as the corresponding portions of the first embodiment. In the second embodiment, only a belt / pulley transmission system 13 as a first drive mechanism is connected to a prime mover (motor M1).
The third drive mechanism is transmitted and connected to the transmission system 13 at a constant speed ratio.

In this case, the second drive mechanism includes a belt / pulley transmission system 23 having a pulley 23a supported on the screw shaft shaft end 5c, the other pulley 23b of the transmission system, and one end supporting the pulley 23b. A transmission shaft 24 extending to the raw water inlet side, and a belt / pulley transmission system 25 including a pulley 25a supported at the other end of the transmission shaft and a pulley 25b supported at the outer end of the rotating shaft 14a. The rotation speed of the shaft 14 a is about twice as large as the rotation speed of the screw 5 in the transmission system 23,
As a result, the high speed of about 2 times the combined magnification (about 4 times) is obtained, and the high speed swinging of the movable plate 12 in the first half of the filter tube is provided.

The third drive mechanism is constituted by a gear train composed of a gear 26 supported on the screw shaft shaft end 5c and a gear 27 supported on the rotating shaft 14b and meshing with the gear 26. : 1, the rotation shaft 14b is rotated at about twice the screw rotation speed. In this case, the rotation speed of the movable plate 12 in the latter half portion 2b of the filter tube is about one half of the swing speed in the first half portion 2a of the filter tube, and the movable plate swing speed of the latter half portion in this case. Is satisfied from the first half.

[0022]

As described above, according to the present invention, the swinging speed of the movable plate in the filter tube is varied between the first half and the second half in accordance with the dehydration or concentration of the phase to be treated. Provide a multi-plate screw press filtration device or concentrator with excellent dewatering and recovery by preventing clogging of the filtration clearance and preventing the phase to be treated (concentrated cake) from being drawn into the filtration clearance in the latter half. Is what you do.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing the overall structure of a multi-plate screw press filtration device according to a first embodiment of the present invention.

FIG. 2 is a sectional view taken along the line AA of FIG.

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

FIG. 4 is a longitudinal sectional view showing the entire structure of a multi-plate screw press filtration device according to a second embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Inlet room 2 Filter tube 3 Outlet room 4 Cylindrical space 5, 5 'screw 5a Main screw shaft 6 Outlet valve 7 Coil spring 8 Filter tube rear end plate 9 Filter tube front end plate 10 Support rod 11 Fixed plate 12 Movable plate 13, 15 Belt pulley transmission system 14a, 14b Rotary shaft 16 Cam key

Claims (3)

[Claims] 1. A filter tube comprising a plurality of annular fixed plates and a number of annular movable plates, each of which has an alternately overlapping arrangement with a minute filtration gap therebetween, and a screw penetrating the entire length of the filter tube. A first driving mechanism for driving the screw to rotate, and a second driving mechanism for driving the movable plate for each part so that the movable plate swings at different speeds in the first half and the second half of the filter tube. A screw press device comprising a driving mechanism and a third driving mechanism. 2. The first driving mechanism is connected to a prime mover, and the second and third driving mechanisms are respectively transmitted and connected to the first driving mechanism at a constant speed ratio, and the second driving mechanism is connected to the first driving mechanism. The swing speed of the first half of the filter tube driven by
2. The apparatus according to claim 1, wherein the swing speed of the latter half of the filter cylinder driven by said drive mechanism is higher than the swing speed. 3. The apparatus according to claim 1, wherein a second screw blade is added between the pitches of the screws penetrating the entire length of the filter tube in the latter half of the filter tube.