JP2004195309A - Cake discharging unit of continuous filter press - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cake discharging unit in which a cake discharging position and a back pressure regulating valve at a cake discharging port are simplified to improve the cake discharging property of this unit so that the sealing property and dehydration property of a continuous filter press are improved. <P>SOLUTION: Since the cake discharging port (16) of an impeller (13) arranged filtration chamber (4) is opened sideways in the lower half part of an outer ring (2) of the chamber (4), the cake discharging state can be observed, the back pressure of the back pressure regulating valve (17) arranged at the port (16) can be managed easily and the moisture content of the dehydrated cake can be controlled. A filtrate and washing water do not intrude into the port (16) because the port is opened sideways. Since the height of the port (16) is made to be (1/3-2/3)D and the bottom line of the port (16) is made to be (0-1/4)D when the diameter of the impeller (13) is defined as D, the kinetic energy of the dehydrated cake at the port (16) can be made higher, the impeller (13) can be rotated at a lower speed and the pressure of original water when fed forcibly to the continuous filter press can be set lower. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a continuous pressurized dewatering machine that presses a stock solution such as industrial wastewater sludge and sewage sludge into an annular filtration chamber and discharges a filtrate from a filter plate while concentrating the stock solution with an impeller to concentrate and dewater the solution. More specifically, the present invention relates to an improvement of a cake discharging device of a continuous pressure dehydrator.
[0002]
[Prior art]
Conventionally, a filtration chamber is formed by a disk-shaped filtration plate and a filter chamber outer ring, and a rotatable impeller is disposed in the filtration chamber, and the undiluted solution press-fitted from the center of the filtration chamber is rotated by the impeller. , The frictional resistance generated between the filter plate and the undiluted solution, and the shear frictional resistance between the cake and the undiluted solution laminated on the filtration surface, causing dehydration and dewatering. A continuous pressure dehydrator for removing cake from the outlet of the outdoor ring has been proposed in Patent Document 1 by the applicant of the present invention. Patent Document 1 proposes a device in which an outlet is installed at a position inclined approximately 45 ° from the vertical line of a filter plate, and a back pressure adjusting valve for increasing or decreasing the opening amount is provided at the outlet.
[0003]
[Patent Document 1]
WO 00/16970, a republished patent, (page 4, lines 34 to 39 of the detailed description of the invention, and FIG. 2 in the drawings)
[0004]
[Problems to be solved by the invention]
A device provided with a back pressure adjusting valve for increasing or decreasing the opening amount at the cake discharge port of the conventional continuous pressurized dewatering machine can also reduce the water content and obtain a uniform cake. Is installed at a position inclined approximately 45 ° from the vertical line of the filter plate.The cake outlet provided at the lower part of the filter plate cannot observe the cake discharge status, and requires the installation and adjustment of the back pressure adjusting valve. There were difficulties in maintenance. Since the filtrate and the washing water overlap with each other, there is a problem of leakage. An object of the present invention is to improve cake dischargeability by changing a cake discharge position. And the back pressure control valve which simplifies a cake discharger and improves a sealing property and a dehydration property is provided.
[0005]
[Means for Solving the Problems]
The gist of the present invention is that a filtration chamber is formed by a disc-shaped filtration plate having a pair of filtration surfaces and an annular outer ring of a filtration chamber, and an impeller is disposed in the filtration chamber, and the inner periphery of the filtration plate In a pressurized dehydrator for supplying the undiluted solution from the fixed inner ring support cylinder to the filtration chamber, a cake discharge port was opened laterally in the lower half of the filter chamber outer ring, and a back pressure adjusting valve was provided at the cake discharge port. This makes it possible to observe the state of cake discharge, to enable back pressure operation with a back pressure adjusting valve, and to control cake moisture. Since the cake outlet is opened sideways, the filtrate and the washing water do not mix into the cake. Then, mounting, adjustment and maintenance of the back pressure adjusting valve are facilitated.
[0006]
The cake outlet of the filtration chamber has a height of (1/3 to 2/3) D with respect to the blade diameter D of the impeller, and a bottom line of the cake outlet with (0 to 1/4) D. Therefore, the component force of the impeller blades to the outer ring of the filter chamber increases, and the kinetic energy of the dewatered cake at the discharge port increases, so that the cake moisture can be reduced. The impeller can be operated at a low speed, and the press-in pressure can be set lower. If a lubricating member is attached to the discharge port, the frictional resistance of the discharge portion is reduced, and the discharge property of the cake is improved. The back pressure adjusting valve provided at the cake discharge port is a flap valve, and a back pressure is applied to the filtration chamber, so that the cake moisture can be adjusted.
[0007]
If the back pressure adjusting valve provided at the cake discharge port is composed of a flexible tubular body fixed to the cake discharge port and a diaphragm fitting holding this flexible material between a fixed plate and a sliding plate, A tubular body that is flexible in terms of the shape, size, position, etc. of the discharge port can flexibly cope with it, making design and assembly easy. Since the cake discharge port can be completely sealed with a flexible tubular body, liquid leakage can be prevented. Since the number of parts is small, the structure is simple, and the assembling time is short, the device price is very low. In addition, the squeezing fitting may be such that the fixed plate and the sliding plate are squeezed and inclined from the filtration chamber side to the discharge side, and the tubular body fixed to the cake discharge port widens the inside of the machine to smoothly form the cake. Emission is possible. In addition, if the cylindrical squeezing metal fittings are arranged in two stages, the cake can be pressed and decompressed by applying back pressure. If the cylindrical body is made of a filter cloth or a resin filter medium, dehydration can be performed with the cylindrical body, so that the formation of the cake is hastened and the cake having a low water content can be taken out.
[0008]
BEST MODE FOR CARRYING OUT THE INVENTION
The apparatus according to the present invention is configured as described above, and the cake discharge port of the filtration chamber is opened laterally in the lower half of the outer ring of the filter chamber. The back pressure can be controlled by the regulating valve, so that the filtrate and the washing water do not enter the cake. The back pressure adjustment valve at the cake discharge opening that opens sideways facilitates back pressure operation, setting the injection pressure lower, enabling low-speed operation of the impeller and control of cake moisture, reducing cake moisture. I can do it. Installation, adjustment and maintenance of the back pressure adjusting valve are facilitated. Further, if the back pressure adjusting valve is a flexible cylindrical body, the cake discharge port can be completely sealed, and liquid leakage can be prevented. The flexible material that attaches to the cake discharge port does not require any connection, and is extremely easy to assemble.
【Example】
FIG. 1 is a longitudinal sectional view of a continuous pressure dehydrator according to the present invention, showing a cake discharging device of the continuous pressure dehydrator according to the present invention. An annular filter chamber outer ring 2 is connected to an outer peripheral end of the plate-shaped filter plates 1 and 1, and an inner ring support cylinder 3 is connected to an inner peripheral end thereof. A filtration chamber 4 is formed. Filter plate spacers 5 and 6 are connected before and after the inner ring support tube 3, and a liquid supply chamber 7 is formed inside the inner ring support tube 3. An undiluted liquid supply pipe 8 is supported by one of the filter plate spacers 5 and is open to the liquid supply chamber 7. The undiluted liquid supplied from the liquid supply pipe 8 is press-fitted into the liquid supply chamber 7, and a circle is formed from the liquid supply chamber 7. It is allowed to flow into the filtration chamber 4 in the circumferential direction. The undiluted solution press-fitted into the filtration chamber 4 separates the filtrate from the filtration surface of the filtration plate 1 to form a cake layer on the filtration surface of the filtration plate 1.
[0010]
As shown in FIG. 1, the mounting seat 9 of the other filter plate spacer 6 is connected to a frame 10 to support a continuous pressure dehydrator. A drive shaft 12 is supported by a bearing 11 of the filter plate spacer 6 on the frame 10 side, and an impeller 13 disposed in the filtration chamber 4 is fixed to the drive shaft 12 extending to the liquid supply chamber 7. . An impeller drive 14 disposed on the frame 10 is interlockingly connected to the rear end of the drive shaft 12. Reference numeral 15 denotes a filter medium frame for reinforcing the filtration surface of the filter plate 1. FIG. 2 is a cross-sectional view of a continuous pressurized dehydrator provided with a flap valve, in which a side edge and a tip end of an impeller 13 are brought close to a filter plate 1 and a filter ring 2. In the embodiment of the present invention, the impeller 13 is configured such that the impeller 13a of the impeller 13 is bent into four straight pieces to approximate a curved line, and is retracted rearward in the rotational direction.
[0011]
By operating the impeller driving device 14, the blade 13a of the impeller 13 scrapes the thin cake layer while sliding on the filtration surface of the filter plate 1, and regenerates the filtration surface of the filter plate 1 while conveying the cake. The blades 13a in the vicinity of the filter outer ring 2 where the water content of the cake is reduced increase the rotating wedge action force and the force for moving the cake in the radial direction, and give a large shear force to the cake. In the embodiment of FIG. 2, a flap valve 19 which is opened and closed by an air cylinder 18 is provided as a back pressure adjusting valve 17 at the cake discharge port 16. The pressure of the undiluted solution in the filtration chamber 4 is generated by adjusting the opening of the cake discharge port 16 of the filtration chamber 4.
[0012]
FIG. 3 is a side view of the filtration chamber in which the impeller is disposed. The cake discharge port 16 of the filtration chamber 4 is provided in the lower half of the filtration chamber outer ring 2 in a horizontal direction. The cake discharge port 16 provided sideways in the filtration chamber 4 allows the observation of the state of cake discharge and enables control of cake moisture. Since there is no cake outlet 16 below the filtration chamber 4, the filtrate and the washing water do not mix into the cake. Then, the mounting, adjustment and maintenance of the back pressure adjusting valve 17 are facilitated. The height of the cake discharge port 16 attached horizontally to the filtration chamber 4 is (1/3 to 2/3) D with respect to the blade diameter D of the impeller 13, and the bottom line a of the cake discharge port 16 is (0). １ ／) D, the component force of the impeller 13 to the outer ring 2 by the blade 13 a increases, the kinetic energy of the dewatered cake at the cake outlet 16 increases, and the water content of the cake can be reduced. The impeller 13 can be operated at a low speed, and the press-fit pressure can be set lower. If a lubricating member such as a fluororesin or ultra-high molecular weight polyethylene is adhered to the inner wall of the cake discharge port 17, the frictional resistance of the cake discharge becomes small.
[0013]
FIG. 4 shows another embodiment of the back pressure adjusting valve, in which a tubular body 20 in which flexible plate rubber is wound in a tubular shape is fixed to the cake discharge port 16 of the filtration chamber 4. The opening of the cake discharge port 16 is very easy to assemble since the flexible tubular body 20 is only attached and there is no connection. The tubular body 20 is inexpensive because a commercially available plate rubber can be used, and any flexible member such as cloth or resin material can be used. An aperture fitting 21 for opening and closing the outlet of the cylindrical body 20 is disposed on the cylindrical body 20 fixed to the cake outlet 16 of the filtration chamber 4.
[0014]
FIG. 5 is a side view of the drawing fitting. The drawing fitting 21 has a fixing plate 22 in contact with the side surface of the cylindrical body 20, and a guide frame 23 connected to the fixing plate 22 extends around the cylindrical body 20. Surrounding. An air cylinder 25 supported on the guide frame 23 is connected to a slide plate 24 slidable on the guide frame 23, and the slide plate 24 is moved along the guide frame 23 by the air cylinder 25 as shown in FIG. The cylindrical body 20 is held between the fixed plate 22 and the sliding plate 24 by sliding. By adjusting the pressure of the air cylinder 25 according to the state of the discharged cake, efficient dehydration can be performed. Because of the mechanism for sandwiching the flexible tubular body 20, there is no gap in the structure, it is completely sealed, and there is no liquid leakage.
[0015]
The fixing plate 22 and the sliding plate 24 of the squeezing fitting 21 are squeezed and inclined from the filtration chamber 4 side to the discharge side, and if the discharge port of the cylindrical body 20 fixed to the cake discharge port 16 is inclined, it is smooth. The cake can be discharged. The squeezing fittings 21 of the tubular body 20 may be arranged in two stages, and the cake can be pressed and dewatered. If the tubular body 20 is made of a filter cloth or a resin filter medium, dewatering can be performed while cake is discharged. Since the drawing metal fitting 21 has a small number of parts and few machining points, and has a short assembling time, the apparatus price is very low. Further, since it is possible to flexibly respond to conditions such as the shape, size, and position of the cake discharge port 16, design and assembly are easy.
[0016]
【The invention's effect】
The cake discharging device of the continuous pressurized dewatering machine of the present invention is configured as described above, and by devising the cake discharging position and simplifying the back pressure adjusting valve at the cake discharging port, the cake discharging property is improved. Is improved, and the sealing property and the dewatering property are improved. That is, in the conventional continuous pressure dehydrator in which the cake discharge port is provided below the filter plate, the state of cake discharge cannot be observed, and there is a difficulty in mounting, adjusting, and maintaining the back pressure adjusting valve. Since the filtrate and the washing water overlap with each other, there is a problem of leakage. However, in the present invention, the discharge port of the filtration chamber is opened laterally in the lower half of the outer ring of the filtration chamber. Since the back pressure adjusting valve is provided at the cake discharge port, the discharge state of the cake can be observed, the back pressure can be controlled by the back pressure adjusting valve, and the cake moisture can be controlled. Since the cake outlet is opened sideways, the filtrate and the washing water do not mix into the cake. Then, mounting, adjustment and maintenance of the back pressure adjusting valve are facilitated.
[0017]
The height of the cake outlet of the filtration chamber is (1/3 to 2/3) D with respect to the blade diameter D of the impeller, and the bottom line of the cake outlet is (0 to 1/4) D. Therefore, the component force of the impeller blades to the outer ring of the filter increases, and the kinetic energy of the dewatered cake at the discharge port increases, so that the cake moisture can be reduced. The impeller can be operated at a low speed, and the press-in pressure can be set lower. In addition, if a lubricating member is attached to the cake discharge port, the frictional resistance of the discharge portion is reduced, and the cake dischargeability is improved. Since the back pressure adjusting valve provided at the cake discharge port is a flap valve, a back pressure is applied to the filtration chamber, and the water content of the cake can be adjusted.
[0018]
If the back pressure adjusting valve provided at the cake discharge port is composed of a flexible tubular body fixed to the cake discharge port and a diaphragm fitting holding this flexible material between a fixed plate and a sliding plate, the cake discharge valve is provided. A tubular body that is flexible in terms of the shape, size, position, and the like of the outlet can flexibly cope with it, which facilitates design and assembly. Since the cake discharge port can be completely sealed with a flexible tubular body, liquid leakage can be prevented. Since the number of parts is small, the structure is simple, and the assembling time is short, the apparatus price is very low. Then, the squeezing metal fitting may be such that the fixed plate and the sliding plate are squeezed and inclined from the filtration chamber side to the discharge side, and the tubular body fixed to the cake discharge port widens the inside of the machine to smoothly form the cake. Emission is possible. In addition, if the squeezing metal fittings of the cylindrical body are arranged in two stages, the cake can be pressed and dewatered by applying back pressure. In addition, if the tubular body is made of a filter cloth or a resin filter material, dehydration can be performed with the tubular body, the formation of the cake can be accelerated, and the cake having a low water content can be taken out.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view of a continuous pressure dehydrator according to the present invention.
FIG. 2 is a cross-sectional view of a continuous pressurized dehydrator provided with a flap valve.
FIG. 3 is a side view of a filtration chamber provided with an impeller.
FIG. 4 is a conceptual diagram of a continuous pressurized dehydrator in which a squeezing fitting is arranged at a cake discharge port.
FIG. 5 is a side view of the drawing fitting with the outlet of the tubular body opened.
FIG. 6 is a side view of the drawing fitting with the outlet of the cylindrical body closed.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Filtration plate 2 Filtration chamber outer ring 3 Inner ring support cylinder 4 Filtration chamber 13 Impeller 16 Cake discharge port 17 Back pressure regulating valve 19 Flap valve 20 Tubular body 21 Shrink fitting 22 Fixed plate 24 Sliding plate D Blade diameter a Bottom line

Claims (8)

A filter chamber (4) is formed by a disc-shaped filter plate (1, 1) having a pair of filter surfaces and an annular filter chamber outer ring (2), and an impeller (13) is arranged in the filter chamber (4). And a lower half of the outer ring of the filter chamber (2) in a pressurized dehydrator that supplies a stock solution from the inner ring support cylinder (3) fixed to the inner peripheral end of the filter plate (1) to the filtration chamber (4). A cake discharge device for a continuous pressurized dewatering machine, characterized in that a cake discharge port (16) is opened laterally in the section and a back pressure regulating valve (17) is provided in the cake discharge port (16). With respect to the impeller diameter (D) of the impeller (13), the height of the cake outlet (16) is set to (1/3 to 2/3) D, and the bottom line (a) of the cake outlet (16) is The cake discharging device for a continuous pressurized dehydrator according to claim 1, wherein (0 to 1/4) D is set. The cake discharging device for a continuous pressurized dehydrator according to claim 1 or 2, wherein a lubricating member is attached to the cake discharging port (16). 4. The cake discharging device for a continuous pressurized dehydrator according to claim 1, wherein the back pressure regulating valve is a flap valve (19) provided at a cake discharging port (16). 5. . The back pressure regulating valve (17) has a flexible tubular body (20) secured to the cake discharge port (16), and the tubular body (20) is fixed to a fixed plate (22) and a sliding plate (20). The cake discharging device for a continuous pressurized dehydrator according to any one of claims 1 to 3, further comprising a squeezing fitting (21) sandwiched in (24). The above-mentioned drawing metal fitting (21) is a cylindrical body fixed to the cake discharge port (16) by squeezing the fixed plate (22) and the sliding plate (24) from the filtration chamber (4) side toward the discharge side. The cake discharging device for a continuous pressurized dehydrator according to claim 4 or 5, wherein (20) is opened and closed. The continuous pressurized dewatering machine according to claim 5, wherein the squeezing fittings (21) of the cylindrical body (20) are arranged in two stages. The cake discharging device for a continuous pressurized dehydrator according to claim 6 or 7, wherein the tubular body (20) is a filter cloth or a resin filter medium.

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