JP3779245B2 - Screw type filter dehydrator - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention, for example, a suspension containing suspended fine particles generated in a relatively small-scale sewage treatment operation represented by the oxidation ditch method, etc. The present invention relates to a screw-type filter dehydrator for separating fine particles.
[0002]
[Prior art and its problems]
Conventionally, a large number of annular filtration plates are fixed in a stacked manner with a gap between each other, and the respective annular movable plates are loosely fitted between the respective annular filtration plates, whereby each of the slits is separated from the separation water outflow groove. The outer diameter of the screw blade is larger than the inner diameter of the annular movable plate, with the starting end opening of the filter body serving as a solid-liquid feed port and the terminal opening serving as a dehydrated solid feed port. A screw conveyor formed smaller than the inner diameter of the annular filter plate is fitted into the center hole of the filter body, and when the screw conveyor is driven, the outer peripheral edge of the screw blade is in sliding contact with the inner peripheral edge of each annular movable plate in the radial direction. A screw type filtration and dehydration device that generates an eccentric rotational motion of each annular movable plate is known.
[0003]
Then, by driving the screw conveyor, the annular movable plate performs an eccentric rotational movement along the gap between the annular filtration plates, and the raw sludge water fed into the filtration body from the feeding port advances along the screw blade while moving in the axial direction. In this process, the filtered filtrate flows out from the separated water outflow groove, and the dewatered sludge cake that has been dewatered and has a low water content ratio is sequentially discharged from the front delivery port, but the dewatering efficiency is increased. Therefore, if the eccentric rotational momentum of the annular movable plate is increased, the amount of sludge leakage near the inlet and outlet is increased, and the eccentric rotational momentum of the annular movable plate is reduced to suppress the sludge leakage. In the current situation, it is inevitable that the dewatering efficiency is lowered.
[0004]
OBJECT OF THE INVENTION
An object of the present invention is to provide a screw-type filtration and dehydration device capable of suppressing sludge leakage near the inlet and the outlet and increasing the drainage efficiency at the intermediate portion to perform an effective and appropriate filtration and dehydration operation. More specifically, in the low concentration stage near the inlet, the annular movable plate prevents the sludge floc from being broken and leaked by a small eccentric rotational motion, and in the middle part of the filter body where dewatering efficiency should be increased, the annular movable plate has a large eccentricity. Rotating motion applies a shearing force to the sludge cake to discharge a large amount of liquid, and the annular movable plate suppresses sludge leakage by a small eccentric rotating motion in the vicinity of the delivery port where the internal pressure is increasing. Another object of the present invention is to provide a screw-type filtration and dehydration apparatus in which an effective and appropriate filtration and dehydration operation is performed by a simple operation system.
[0005]
[Structure of the invention]
In the present invention, a large number of annular filtration plates are fixed in a stacked manner with gaps between each other, and the annular movable plates are loosely fitted between the annular filtration plates, thereby separating the slits into separate water outflow grooves. The outer diameter of the screw blade is larger than the inner diameter of the annular movable plate, with the opening at the start end of the filter body serving as a solid liquid feed port and the terminal opening as a dewatered solid feed port. A screw conveyor formed to be larger than the inner diameter of the annular filtration plate is fitted into the center hole of the filter body, and when the screw conveyor is driven, the outer peripheral edge of the screw blade is in sliding contact with the inner peripheral edge of each annular movable plate. In the screw type filter dehydrator that causes each annular movable plate to generate an eccentric rotational movement toward the center of the filter body, The eccentric rotational momentum in the radial direction of the annular movable plate when the screw conveyor is driven is increased in the middle portion of the filter body, and is formed at the intermediate portion of the filter body. It was configured to be small in the vicinity.
[0006]
[Action]
By driving the screw conveyor, the outer peripheral edge of the screw blade is brought into sliding contact with the inner peripheral edge of each annular movable plate, and an eccentric rotational movement in the radial direction is caused in each annular movable plate. In the process in which the sludge raw water fed from the feed port into the filter body advances in the axial direction while swirling along the screw blades, the filtered filtrate flows out from the separation water outflow groove and is dehydrated to have a water content ratio. The dewatered sludge cake that has been lowered is sequentially discharged from the front delivery port, but the eccentric rotational momentum of the annular movable plate is large in the middle part of the filter body and acts small in the vicinity of the feed port and the delivery port. . Therefore, the sludge floc breakage and leakage at the low concentration stage near the inlet are suppressed, and in the intermediate part where the dewatering efficiency should be increased, a shear force is applied to the sludge cake to discharge a large amount of liquid, increasing the internal pressure. The amount of sludge leakage is suppressed near the outlet.
[0007]
【Example】
This will be described with reference to the following practical examples shown in FIGS.
[0008]
Reference numeral 1 denotes a cylindrical filter body, in which a large number of annular filtration plates 2... 2 are fixed in a laminated form while holding required slits, and each annular filtration plate 2. By loosely fitting the movable plates 3, 3, the slits are separated into the water outlet grooves 4, 4, and the outer peripheries of the annular movable plates 3, 3 are eccentric to the outer periphery of the annular filtration plates 2, 2. It has a seat portion 5.. 5 projecting outward from the rotation trajectory, and a space holder 6.. 6 attached to the seat portion 5. Is set to be slightly larger than the wall thickness of each annular movable plate 3. Reference numerals 7... 7 denote fixed bodies that support the respective seats 5... 5 and are constructed so as to be in contact with the annular movable plates 3. The starting end opening of the filter body 1 serves as a solid-liquid feed port 8, and the terminal opening serves as a dehydrated solid feed port 9, and a screw conveyor 11 is fitted into the center hole 10. Reference numeral 12 denotes a prime mover for driving the screw conveyor 11, and 13 denotes a discharge pressure adjusting valve attached to the delivery port 9. The screw conveyor 11 is formed such that the outer diameter M of the screw blade 11B is larger than the inner diameter V of each annular movable plate 3.. 3 and smaller than the inner diameter W of each annular filtration plate 2. Further, the inner diameter V ′ of the annular movable plates 3B... 3B in the filter intermediate part 1B is larger than the inner diameter V of the annular movable plates 3A... 3A in the vicinity of the feeding port 1A and the annular movable plates 3C. The eccentric rotational momentum of the annular movable plates 3A,... 3A in the vicinity of the inlet 1A when the screw conveyor 11 is driven is small, and the eccentric rotational momentum of the annular movable plates 3B,. The eccentric rotational momentum of the annular movable plates 3C... 3C in the vicinity of the delivery port 1C is increased and is reduced.
[0009]
When the prime mover 12 is driven, the screw conveyor 11 rotates, and the raw sewage water fed into the filter body 1 from the feed port 8 advances in the axial direction while turning along the screw blade 11B. The dewatered sludge cake that has flowed out of the separated water outflow grooves 4 and 4 and has been dewatered and has a low water content ratio is sequentially discharged from the front discharge port 9, but is low in the vicinity of the supply port 1 </ b> A. In the concentration stage, the eccentric rotational momentum of the annular movable plates 3A,... 3A is reduced to prevent the sludge floc from being broken and leaked. In the intermediate part 1B of the filter body to be improved in dewatering efficiency, the eccentricity of the annular movable plates 3B,. By increasing the rotational momentum, a shear force is applied to the sludge cake to discharge a large amount of liquid. It will prevent leakage of sludge eccentric rotation of the movable plate 3C · · 3C is decreased.
[0010]
【The invention's effect】
According to the screw type filter dehydrator of the present invention, the annular movable plate prevents the sludge floc from being broken and leaked by a small eccentric rotational motion at a low concentration stage near the inlet, and the intermediate part of the filter body to improve the dewatering efficiency is annular. A large eccentric rotational movement of the movable plate applies a shearing force to the sludge cake to discharge a large amount of liquid, and the annular movable plate suppresses sludge leakage by a small eccentric rotational movement in the vicinity of the delivery port where the internal pressure is increasing. An effective and proper filtration and dewatering operation is performed by an extremely rational operation system.
[Brief description of the drawings]
FIG. 1 is a vertical side view schematically showing a configuration of a screw type filtration dehydration apparatus to be an object of the present invention.
FIG. 2 is a longitudinal sectional side view of a main part of a filter body in the device of the present invention.
FIG. 3 is a longitudinal front view of a filter body in the vicinity of the inlet of the filter according to the present invention.
FIG. 4 is a longitudinal front view of the intermediate portion of the filter body in the device of the present invention.
FIG. 5 is a longitudinal front view in the vicinity of the delivery port in the apparatus of the present invention.
FIG. 6 is a longitudinal front view of a screw conveyor in the device of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Cylindrical filter body 1A Near feed port 1B Filter body intermediate part 1C Near feed port 2 Annular filtration plate 3 Annular movable plate 3A Annular movable plate 3B near an feed port Annular movable plate 3C in an intermediate part of an annular ring Movable plate 4 Separation water outflow groove 8 Solid liquid feed port 9 Dehydrated solid content feed port 10 Filter body central hole 11 Screw conveyor 11B Screw blade M Screw blade outer diameter V Ring movable plate inner diameter V 'Filter body intermediate part Inner diameter W of annular movable plate at

Claims (1)

A cylindrical shape in which a large number of annular filtration plates are fixed to each other with a gap between each other, and each movable slit is loosely fitted between each of the annular filtration plates so that each of the slits serves as a separation water outflow groove. The filter body has a starting end opening as a solid-liquid inlet and a terminal opening as a dehydrated solids outlet, and the outer diameter of the screw blade is larger than the inner diameter of the annular movable plate. A screw conveyor formed smaller than the inner diameter of the filter body is fitted in the center hole of the filter body, and when the screw conveyor is driven, the outer peripheral edge of the screw blade is in sliding contact with the inner peripheral edge of each annular movable plate and is eccentrically rotated in the radial direction. In the screw type filter dewatering device that causes the movement of each annular movable plate, the inner diameter of the annular movable plate in the middle part of the filter body is different from that of the feeding port and the feeding port. It is formed smaller than the inner diameter of the annular movable plate in the vicinity of the outlet, and the eccentric rotational momentum in the radial direction of the annular movable plate when the screw conveyor is driven becomes larger in the middle part of the filter body and in the vicinity of the inlet and outlet. A screw type filter dehydrator characterized by being configured to be small.

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