JPH10156111A - Rotary screen filter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rotary screen filter by which, in order to separate fiber, solid matter or the like contained in night soil, plant waste water and other sewage, filtration is effectively performed for a long time. SOLUTION: A rotary screen filter 1 has a rotary screen 3, or bellmouth 4, the rotary screen and its reinforcing members being covered with a fluororesin, a filtrate discharge port 13 for discharging sewage which has been filtered by the screen surface and has fallen, an excess sewage discharge port 12 for receiving excess sewage flowing out from the lowest part of the screen opening, and an impurity discharge port 11 for receiving impurities falling from the opening a little in front of the lowest part toward the direction of rotation. A washer in which, when an excess outflow of sewage is detected, the supply of sewage is stopped and hot water or water is jetted to the inner surface and/or the outside surface of the rotary screen to wash it, is provided for the filter.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary screen type filtration device used for separating fibers and solids contained in human waste, industrial wastewater and other wastewater.

[0002]

2. Description of the Related Art In recent years, the number of family restaurants has increased,
With the development of the food industry and changes in eating habits, oil is often used in foods, the amount of oil contained in sewage increases, and various problems have occurred in conventional sewage treatment facilities.

[0003]

In the rotary screen type filtration apparatus, for example, clogging of the screen occurs due to an increase in oil content, and the clogging causes excess water to flow out of the screen opening without being filtered. When such wastewater overflows, the operation of the filtration device is stopped,
The screen needs to be cleaned. To perform the cleaning,
A person had to enter the filter and clean it, or remove it and clean it. Dirt and scales stick to the rotating screen itself and cannot be completely cleaned even with chemicals such as caustic soda. When dirt adheres to the rotating screen, the size of the mesh is reduced, so that there are many problems such as the size of the mesh having to be set large in advance.

[0004]

Accordingly, a first aspect of the present invention provides a rotary screen type filtration apparatus in which a rotary screen or a bell mouth, a rotary screen and a reinforcing member thereof are coated with a fluororesin. In the second rotary screen type filtration device of the present invention, the bottom of the cross-sectional triangle of the horizontal wire constituting the mesh of the screen is the inner surface side of the screen, and the bottom of the cross-section of the vertical wire is triangular. The third rotating screen type filtration device of the present invention, which is on the outer surface side of the screen, further comprises a horizontal wire having a triangular cross section with a bottom portion inclined forward in the rotation direction with respect to the screen surface. age,

The fourth rotary screen type filtration device of the present invention further comprises a filtrate discharge port for discharging sewage filtered and dropped on the screen surface, and a sewage excessively flowing out from the lowermost portion of the screen opening. And a contaminant discharge port for receiving contaminants falling from an opening slightly forward in the rotational direction from the lowermost part, and the fifth rotary screen filtration of the present invention. The apparatus shall further include a cleaning device for stopping the supply of the sewage when detecting an excessive outflow of the sewage and jetting hot water or water toward an inner surface and / or an outer surface of the rotating screen to wash the screen. The sixth rotary screen type filtration device of the present invention further stops the supply of sewage at predetermined time intervals, and feeds hot water toward the inner surface and / or outer surface of the rotating screen. The water was ejected and that provided a cleaning device for cleaning the screen,

A seventh aspect of the present invention provides a rotary screen type filtration apparatus further comprising a washing device for jetting hot water or water toward an inner surface and / or an outer surface of the rotating screen at the end of the operation to wash the screen. The eighth rotary screen type filtration device of the present invention further includes a cleaning device for blowing air toward the inner surface and / or the outer surface of the rotating screen to wash the screen. The ninth rotary screen type filtration device of the present invention comprises:
Furthermore, the ejection of air is intermittent in relation to the rotation of the screen.

[0007]

FIG. 1 shows a side view of one example of a filtration device according to the present invention in a partially sectioned view. 1 is a rotary screen type filtration device. 2 is a cylindrical casing,
Reference numeral 2-1 denotes a disk-shaped lid member which is attached to the casing 2 in a water-tight and air-tight manner with a flange or the like, and can be freely removed. 2-2 is a reinforcing plate. Reference numeral 3 denotes a rotating screen, and reference numeral 4 denotes a bell mouth whose cross section is curved in a curved shape such as an arc in this case. Reference numeral 5 denotes a deodorizing pipe for reducing the pressure inside the casing 2 from the atmospheric pressure. 6 is a rotating screen 3
This is an air cleaning pipe that blows off and adheres foreign substances that have been sprayed toward the surface. 8 is 80 degree C inside hot water washing pipe
This is a member for cleaning the rotating screen 3 from the inside by applying pressure to the front and rear hot water or water. Reference numeral 9 denotes a sewage inlet pipe for supplying sewage from a measuring tank (not shown) (see Japanese Patent Application No. 8-153454) to a sewage inlet nozzle 10.

The sewage inlet nozzle 10 can be removed from the sewage inlet pipe 9 at the flange joint. A sewage input path from the measuring tank to the sewage input pipe 9 to the sewage input nozzle 10 is configured. Reference numeral 11 denotes a contaminant discharge port,
-1 is a guide blade. Reference numeral 12 denotes an excess sewage discharge port for discharging excess sewage, and reference numeral 12-1 denotes a sensor for detecting outflow of sewage (for example, by detecting conduction of current between terminals). Reference numeral 13 denotes a filtrate outlet provided on the casing bottom portion 14 of the casing 2. Reference numeral 15 denotes a rotating shaft, 16 denotes a motor with a variable speed reducer, 20-1 and 20-2 denote bearing devices, and 21 denotes a cover. 22, a leg; 23, a base; and 24, a storage unit. 25 is a bearing device 20 installed on the upper surface of the storage portion 24
-1 and 20-2.

FIG. 2 is a front view of the rotary screen type filtration apparatus 1 in a state where the cover member 2-1 is made of a transparent plate or is removed. 7 is an outer hot and cold water washing pipe,
It is a member that applies hot water or water at about 80 ° C. from the outside to apply pressure to perform cleaning. M is an impurity pool. The cross section of the contaminants gathered in a thick rope shape inside the rotating screen 3 is illustrated. When the impurities are formed in such a state, the separation of the impurities from the sewage is performed normally, and the filtration of the sewage is performed normally. FIG. 3 is also a front view of the rotary screen type filtration device 1, and the sewage N that is not filtered due to clogging of the rotary screen 3 is excessively discharged from the opening of the rotary screen 3 through the sewage discharge port 12 (shown in cross section). ) Shows the state when flowing. When the sensor 12-1 detects this, the supply of the sewage to the sewage inlet pipe 9 to the sewage inlet nozzle 10 is stopped.

FIG. 4 shows a rear view of the rotary screen type filtration device 1 with the cover 21-1 of the cover 21 removed.
17 is a sprocket or pulley on the motor side, 18
Is connected to the rotating shaft 15 by a friction clutch with a sprocket or pulley on the rotating shaft side. 19 is a chain or a belt. 24-1 and 24-2 are doors provided in the storage unit 24. FIG. 5 is a side view and a front view of the rotating screen 3. FIG. 6A is a cross-sectional view of the AA portion of the rotating screen 3 shown in FIG. The mesh of the rotating screen 3 is formed by a horizontal wire 3-1 and a vertical wire 3-2.
Although stainless steel is used for the wire, any wire having appropriate strength and capable of being coated with a fluororesin may be used. 3
-a shows an example of a cross section of the horizontal wire 3-1. E indicates a horizontal wire width, F indicates an interval between the horizontal wires 3, and G indicates a height. FIG. 6B shows another example 3-b of the cross section of the horizontal wire. FIG. 6C shows still another example of the cross section of the horizontal wire 3-c.
Is shown. H is a step.

FIG. 7 is an enlarged sectional view of a portion B in FIG. 3-2 indicates a vertical wire, and 3-3 indicates a screen frame. J is the height, K is the width, and L is the interval. One example is E = 1.5mm, F = 1.0mm, G = 3.0mm,
= 0.1-0.2 mm, J = 4.0 mm, K = 2.5 mm, L = 24 mm, the inner diameter of the rotating screen 3 is 1400 mm, and the outer diameter is 1424 mm. FIG. 8 is a cross-sectional view illustrating a mounting configuration of the rotating screen 3 when mounted on the rotating shaft 15. 3-1 is a horizontal wire, 3-2 is a vertical wire, 3-3 is a screen frame, 3-4
Denotes an attachment plate, 3-5 denotes an opening plate, and 3-6 denotes a substrate. 3
Reference numeral -7 denotes a reinforcing plate, which is not shown in the present embodiment.
Two are provided. 3-8 is a shaft mounting plate. 4 indicates a linear bell mouth in this case.

The mounting plate 3-4, the substrate 3-6, and the shaft mounting plate 3-8
A relative position is secured by, for example, a positioning pin or the like, and the assembly is removably attached and fixed with, for example, a bolt and a nut so as to be assembled.
The shaft mounting plate 3-8 is integrally fixed to the rotating shaft 15. The mounting plate 3-4 of the rotating screen 3 has a feed portion 3-9 having an inclined portion inclined with respect to the axis of the screen.
It is attached to one place (or one place). The feed portion 3-9 rotates so as to push the rear end of the contaminant pool M toward the opening of the rotating screen 3 at the inclined portion.

The fluororesin film is formed on the entire rotating screen 3, but may be formed by attaching a bell mouth 4 and a mounting plate 3-4, which is a reinforcing member, an opening plate 3-5, and a reinforcing plate 3-7. Alternatively, the process may be performed including the substrate 3-6 and the shaft mounting plate 3-8. Fluororesin is a general term for fluorocarbon polymers (synthetic resins), which are polytetrafluoroethylene, polychlorotrifluoroethylene, tetrafluoroethylene and ethylene, perfluoroalkylvinylether and hexafluoropropylene and their respective copolymers,
Chlorotrifluoroethylene-ethylene copolymer, polyvinylidene fluoride, polyvinyl fluoride and the like. The coating is generally performed by suspending a polymer powder in a solvent, spraying the suspension, and baking in a furnace.

FIG. 9 shows a horizontal wire 3-1 and a vertical wire 3-2.
The relationship between the rotation direction of the sewage and the supply of sewage from the sewage injection nozzle 10 is shown. Providing the step H is more effective for filtering sewage. FIG. 10 shows the relationship between the rotation of the rotating screen 3 and the arrangement of the air washing pipes 6-1 and 6-2, the outer hot and cold water washing pipe 7, the inner hot and cold water washing pipe 8, and the waste water charging nozzle 10. Impurities adhering to the inner surface of the rotating screen 3 are caught in M-1
At M-2, the rotary screen 3 is peeled off from the horizontal wire 3-1 (in this case, 3-c). The remaining contaminants are blown off and removed by the inner air cleaning pipe 6-2 and the outer air cleaning pipe 6-1. A reinforcing plate 3-7 is provided on the outer side of the rotating screen 3, but there is no such thing on the inner side.
It can be provided close to one. The air cleaning pipes 6-1 and 6-2 and the hot and cold water cleaning pipes 7 and 8 may be provided with staggered holes as nozzles, or may be provided with a plurality of nozzles having a conventionally known structure. .

The sewage sent from a measuring tank (not shown) to the sewage inlet pipe 9 is injected from the sewage inlet nozzle 10 toward the inner surface of the rotating screen 3. The amount of sewage is relatively large at the back of the rotating screen 3 and is set at a position where filtration is completed before reaching the opening. As shown in FIG. 9, the input wastewater is filtered through the gap between the horizontal wires 3-1 from the input position to the lowermost position. The impurities left unfiltered on the horizontal wire 3-1 are located at a position slightly higher than the lowest position of the rotating screen 3 in the rotating direction due to the centrifugal force and the attractive force of the rotating screen. 2, a contaminant pool M having an elliptical cross section is formed. Horizontal wire 3
As shown in FIG. 10, the contaminants remaining on -1 are taken into the contaminant pool M at M-1 and peeled off from the horizontal wire 3-1 at M-2. When the contaminant pool M has a certain thickness, it does not increase any further, and is sequentially fed toward the opening side of the rotating screen 3.

The mounting plate 3-4 of the rotating screen 3 has a feed portion 3 having an inclined portion inclined with respect to the axis of the screen.
-9 is attached. The feed portion 3-9 rotates so as to push the rear end of the contaminant pool M toward the opening of the rotating screen 3 at the inclined portion. The contaminant pool M extruded into the bell mouth 4 of the opening,
It falls to the impurity discharge port 11. During normal operation in this way, the sewage is filtered by the rotating screen 3, the filtrate flows to the filtrate outlet 13, and the impurities drop to the impurity outlet 11.

However, if there is a change in the components of the sewage or an excessive supply, etc., the mesh of the rotating screen 3 is clogged, and the contaminant pool M disappears immediately, and as shown in FIG. Through the opening of the rotating screen 3 via the bell mouth 4 and the excess wastewater discharge port 12
Flow into When the sensor 12-1 detects the inflow of sewage, the supply of sewage to the sewage inlet pipe 9 is stopped. A stage where the supply of sewage from the sewage injection nozzle 10 is lost (detection may be performed in the sewage input path, or an appropriate time from the detection of excessive outflow of sewage may be determined).
The outer hot water washing pipe 7 and / or the inner hot water washing pipe 8
Hot water of about 0 to 90 ° C. (so that the oil content is not more than about 60 ° C. when it reaches the mesh) or water at room temperature is pressurized and sprayed toward the rotating screen 3. At the stage where the clogging of the screen of the rotating screen 3 is blown off and washed (the light sensor or the like may be directly detected, or an appropriate time from the start of washing may be set), Supply of hot water or water is stopped and sewage is supplied again.

If it is known to be used continuously for a long period of time, for example, a fixed time is determined using a timer or the like, the supply of sewage is stopped, and the rotating screen 3 is mounted. Hot water or water is sprayed onto the inner surface and / or the outer surface under pressure to clean the inner surface and / or the outer surface. At the end of operation or for a certain period of time, for example, 5 minutes, when it is detected that there is no flow of sewage or no sewage in the sewage introduction path, the inner surface and / or outer surface of the rotating screen 3 is similarly attached. Hot water or water is injected under pressure to wash. Since the rotating screen 3 itself or the reinforcing member thereof and the bell mouth 4 are covered with a fluororesin, the occurrence of clogging is extremely reduced, and M-1 which forms the contaminant pool M, The winding and stripping in M-2 can be performed smoothly, and the rotating screen 3 can be washed very effectively by spraying hot water or water. It is almost unnecessary to remove the rotating screen 3 and clean it with a chemical such as caustic soda. In addition, if the air washing pipes 6-1 and / or 6-2 are constantly operated during operation, the mesh of the rotating screen 3 can be maintained in a normal state, and the rotating screen 3 does not need to be washed with hot water or water. In addition, clogging of the rotating screen 3 can be prevented for a long time, and the operation can be continued. Since the rotating screen 3 is provided with a plurality of reinforcing plates 7 as reinforcing members, the air jetted from the outside may stop jetting at the position of the reinforcing plate.

[0019]

【effect】

1) Since the size of the mesh of the screen or the distance between the horizontal wires can be reduced, for example, to about ２, finer impurities can be removed, and the subsequent processing work becomes easier. 2) The cleaning operation can be performed without removing the screen by spraying air and hot water or water. 3) When the overflow is detected, the supply of the sewage is temporarily stopped, and air and hot water or water are sprayed to wash the sewage with the screen attached. 4) Since it can be washed only with hot water or water without using a chemical, there is no hindrance to the subsequent treatment, for example, treatment with microorganisms. 5) Even if the oily wastewater does not stick to the screen, the filtration operation can be performed continuously for a long time.

[Brief description of the drawings]

FIG. 1 is a partial cross-sectional side view of an example of a rotary screen filtration device of the present invention.

FIG. 2 is a front view of the rotary screen type filtration device 1 as one example of the present invention, showing a state where a cover member 2-1 is transparent or removed.

FIG. 3 is a front view of the rotary screen type filtration device 1 as one example of the present invention, in which the excess sewage discharge port 12 is shown in cross section,
Shown with -1 removed.

FIG. 4 is a rear view of the rotary screen type filtration device 1 as one example of the present invention, with the cover member 21-1 of the cover 21 removed.

5 is a side view and a front view of the rotating screen 3. FIG.

FIG. 6A is a cross-sectional view taken along the line AA of the rotating screen 3 shown in FIG. 6B and 6C show other examples of the cross section of the horizontal wire 3-1.

FIG. 7 is an enlarged cross section of a portion B in FIG. 5;

FIG. 8 is a sectional view showing a mounting configuration of the rotary screen 3 when mounted on the rotary shaft 15.

9 shows the relationship between the rotation of the rotating screen 3 and the supply of sewage from the sewage injection nozzle 10. FIG.

FIG. 10 shows a horizontal wire 3 provided on the rotating screen 3.
-1, air washing pipes 6-1 and 6-2, outer hot and cold water washing pipe 7, inner hot and cold water washing pipe 8, sewage injection nozzle 10, and foreign matter accumulation M
Shows the relationship.

[Explanation of symbols]

 E Triangular wire width F interval G height H step J height K triangle wire width L interval M Contaminant accumulation N Excessive wastewater 1 Rotary screen type filtration device 2 Casing 3 Rotary screen 3-1 Horizontal wire 3-2 Vertical wire 3- 3 Screen frame 3-4 Board 3-5 Opening plate 3-6 Reinforcement plate 3-7 Shaft mounting plate 4 Bell mouth 5 Deodorizing tube 6 Air washing tube 6-1 Outside air washing tube 6-2 Inner air washing tube 7 Outside hot water Washing pipe 8 Inside hot and cold water washing pipe 9 Sewage inlet pipe 10 Sewage inlet nozzle 11 Contaminant discharge port 12 Excessive wastewater discharge port 13 Filtrate discharge port 14 Casing bottom 15 Rotation axis 16 Motor with variable speed reducer 17 Sprocket 18 Sprocket 19 Chain 20- 1 Bearing device 20-2 Bearing device 21 Cover 22 Leg 23 Base 24 Storage unit 24-1 Door

Claims (9)

[Claims] 1. A rotary screen type filtration apparatus wherein a rotary screen or a bell mouth, a rotary screen and a reinforcing member thereof are coated with a fluororesin. 2. A triangular cross section of a horizontal wire constituting a mesh of a screen has a bottom portion on an inner surface side of the screen.
2. The apparatus according to claim 1, wherein the bottom of the triangular cross section of the vertical wire is on the outer surface side of the screen. 3. The apparatus according to claim 2, wherein the bottom of the triangular cross section of the horizontal wire is inclined forward in the rotation direction with respect to the screen surface. 4. A filtrate discharge port for discharging sewage which is filtered and falling on the screen surface, an excess sewage discharge port for receiving sewage excessively flowing from the lowermost portion of the screen opening, and rotating from the lowermost portion. 4. The apparatus according to claim 1, further comprising a contaminant discharge port for receiving contaminants falling from an opening slightly forward in a direction. 5. A cleaning device for stopping the supply of sewage when an excessive outflow of sewage is detected and jetting hot water or water toward an inner surface and / or an outer surface of the rotating screen to wash the screen. The device of one of 1-4. 6. A cleaning device for stopping supply of sewage water at predetermined time intervals, and for flushing hot water or water toward an inner surface and / or an outer surface of a rotating screen to wash the screen. The device of 1 of 5 thru | or 5. 7. The apparatus according to claim 1, further comprising a washing device for jetting hot water or water toward an inner surface and / or an outer surface of the rotating screen at the end of the operation to wash the screen. 8. The apparatus according to claim 1, further comprising an air cleaning device for blowing air toward an inner surface and / or an outer surface of the rotating screen to clean the screen. 9. The apparatus of claim 8, wherein the jet of air is intermittent in relation to the rotation of the screen.