JPS589612Y2 - Multistage liquid “filtration” device - Google Patents

Description

[Detailed description of the invention] The present invention relates to a continuous filtration device for liquids, and in particular, it continuously filters raw water (water to be treated) whose physical properties and amount of contained suspended matter vary, and always maintains the amount of filtrated water above a certain quality. This invention relates to a multi-stage liquid swelling device suitable for obtaining liquids.

Suspended matter contained in raw water that should normally be filtered can change significantly in the short or long term due to a combination of complex factors such as its generation process, treatment process, degree of eutrophication, and other natural influences. Therefore, even in such cases, water filtration equipment is required that can always maintain a water quality higher than a predetermined level and a flow rate of water.

Conventionally, the treatment equipment used for the above purpose is to place a net around a rotating cylinder, make it semi-submerged, supply raw water into the cylinder, and drain the raw water from the inside of the cylinder to the outside. Then, water or air is sprayed from the outside of the cylinder protruding above the raw water toward the inside to separate the solid substances to be filtered, which is then received by a hopper installed inside the cylinder and discharged to the outside. There are devices that pass through a sand layer (rotating cylinder single filtration device), and a sand bed filtration device that passes through a button and a layer of sand.

In the rotating cylinder single filtration device, only about 70% of the outer circumference of the cylinder is submerged in water, so the effective filtration area is small, pressured water or compressed air is required to remove the filtered material, and the filter body is made of wire mesh. Because it is formed of a fixed primary surface made of pulverized coal and blue-green algae, particles with small particle diameters such as pulverized coal and blue-green algae, or elongated particles such as diatoms pass through without passing through, reducing the permeation efficiency.

As a countermeasure to this problem, it would be possible to make the wire mesh finer, but this would not only require a large amount of high-pressure washing water or compressed air to remove the clogging of the filtered material, but also reduce the amount of water flow due to increased water flow resistance. do.

In addition, the stainless steel wire mesh with fine mesh that constitutes the filter body is inferior in durability, so the filter body inevitably becomes larger, but this has the disadvantage of increasing equipment costs and maintenance costs.

In addition, floating materials with high water content, such as biologically oxidized flocs and metal hydroxide flocs, are extremely susceptible to shear failure and are crushed by a pressure difference of about 150 mmAq while passing through a wire mesh, which is not the intended purpose. The filtration efficiency is unsatisfactory.

In the latter type of sand filtration equipment, the p filtration principle is thick layer filtration, which is superior to rotary cylindrical filtration equipment in terms of filtration efficiency. has the advantage of free movement of sand particles and can be expected to be somewhat effective, but if there are changes in the suspended matter contained in the raw water and you are trying to continuously obtain water quality and filtrate amount that are higher than the specified quality. However, it is necessary to install multiple long drainage facilities, and this becomes expensive due to the automated instrumentation.

In addition, the amount of water required during intermittent back pressure washing is large, which is insufficient in terms of the overall efficiency of solid-liquid separation, which is the original objective.

As mentioned above, the rotating cylindrical filtration device and the sand filtration device each have their own problems, but in order to solve these problems, the filter body is a rotating body submerged in water, and compared to the sand filtration device with the same projected area. A rotary filtration device has been proposed in the past that has a flow area 73 times or more larger and performs surface filtration with long-haired fibers lying down.

(Japanese Patent Application Laid-open No. 51-119168) This device has low water flow resistance, the f-way linear velocity is more than three times that of a normal sand filtration device, and the amount of filtrated water per facility area is more than 10 times that of an Ff filtration device. By selecting the length, number, diameter, and material of the long fibers that make up the filter according to the physical properties of the suspended solids and the intended conditions, water flow resistance and filtration accuracy can be adjusted as desired. , and can be easily replaced within a short period of time.

In addition, a back pressure cleaning mechanism that utilizes the water head pressure of the filtrate or suction from the outside is installed in a part of the filter surface, so filtration and removal of filtrate are performed continuously and in parallel, resulting in regular processing. It also has the advantage that during back-pressure washing, the long-pile fibers stand up and move freely, so that the substances to be filtered adhering to the fiber surfaces are completely removed in a short period of time.

However, as mentioned above, suspended matter contained in raw water is composed of various miscellaneous combinations, and when the raw water changes in physical properties and quantity, it is possible to achieve a specified r
It is difficult to maintain water flow rate and water quality, and even if a satisfactory facility were to be constructed, it would be a lengthy facility, making it extremely uneconomical.

The floating substances contained in raw water are various and miscellaneous, and no matter how good the rotary filtration apparatus using the long fibers described above is, it is difficult to treat them with a single unit.

For this reason, it is conceivable to divide the area where the floating objects are located and use several rotary sifting devices suitable for the area, but this method inevitably increases the equipment cost.

The present invention takes advantage of the excellent filtration function of a rotary filtration device using P cloth with long fibers, and provides a device that can handle the filtration of various types of suspended matter and can be further compacted. It is.

In order to achieve the above object, the filtration device of the present invention uses fibers with a pile of 20 to 80 mm and a basis weight of 400 to 1000 g//m.
A plurality of filtration device bodies are connected in series, in which a filter body made of P cloth with flocked base cloth stretched over the outer circumferential surface of a drum-shaped cage is rotatably supported on a hollow shaft, and the filter body is submerged in a water tank. the filtration device bodies are arranged one after another, and the filtrate from the hollow shaft is sequentially supplied into the water tank of the next filtration device main body by forming a water head difference between the adjacent filtration device main bodies, and a hopper having a slide plate with an opening attached to the upper part that contacts the filter body is installed below the filter body and is connected to the drain pipe, and the hopper is squeezed into the hopper, and/or the upper and lower sides of the slide plate are attached. It is characterized by the provision of a button and an inclination adjustment means.

According to the device according to the present invention, even if the characteristics of suspended matter change, it is possible to easily cope with the change, and it provides a device that always obtains a predetermined water quality and p-excess amount.

Next, embodiments of the present invention will be described with reference to the drawings.

In the side sectional view of the multi-stage liquid filtration device shown in Fig. 1, reference numerals 1 and 2 are rotating filter bodies, each rotating filter body is drum-shaped, and although details are not shown, two circular side plates are used. A number of stays (horizontal bars) are installed at appropriate intervals around the periphery to form a kind of cylindrical shape, and the outer circumference of the body has 20 to 80 mm of pile.
Synthetic fibers with fibers of 1.5 to 20 denier with zero retention so as to satisfy the condition of basis weight of 400 to 10,100 O/rr12)
Sawa cloths 11 and 12, which are made of fiber-flocked base cloth, are stretched around the outer periphery, and the water to be treated is configured to pass from the surface to the back surface of the r cloths 11 and 12 in the body of the rotary filter body. .

A common drive shaft and water conduit pipe 31 is fixedly installed through the center of each of the two rotating flow bodies, and the drive shaft 31 is driven by a motor and a transmission 20 installed outside through a Sugerocket, a chain 21, etc. It is driven by

The rotary filter bodies 1 and 2 are respectively attached to a first raw water tank 3 and a second raw water tank 4 in a submerged manner to form a main body of the filtration device.

Reference numerals 5 and 6 indicate back pressure washing hoppers installed upward from the bottom of each raw water tank. ,6
The outlet pipes 7 and 8 are provided with valves 9 and 10, and are configured to drain the water outside the filtration device, for example, into a sedimentation tank, while adjusting the amount of water discharged by these valves.

13 is an overflow tank adjacent to the second raw water tank, and 14 is a discharge port for filtered water.

The drive shaft and water guide pipe 31 has a slit 15 communicating with the inside of the rotating filter 1, a slit 16 communicating with the second raw water tank 4,
A slit 17 that communicates with the inside of the rotary filter body 2 and a slit 18 that communicates with the overflow tank 13 are provided, respectively.

A partition 31a is provided at a portion of the water guide pipe 31 that supports the rotary filter body 2.

Reference numeral 19 is a water level setting pipe made of a short pipe, which can be freely inserted into the overflow pipe 22, and by changing its length, the operating liquid level of the first raw water tank 3 can be adjusted and set.

Similarly, the operating liquid level of the second raw water tank 4 is adjustable by the water level setting pipe 22.

Overflow weir plate 2 provided between perfusion tank 13 and discharge port 14
4 is vertically adjustable with a bolt set, and can be set at an appropriate position while checking the water level in the weir provided at the top.

The overflow weir plate 24 is formed, for example, in the shape of a triangular weir or a square weir, and is provided with a scale so that perfusion can be regulated accurately.

25 is an overflow pipe of the second raw water tank 4, 26 is a nosave tank, and 27 is a liquid level gauge, which controls a pump 28 that returns overflow water in the second raw water tank 4 to the first raw water tank 3.

29 is a return pipe, 30 is a raw water tank, 32 is a raw water supply pump, and 33 is a raw water pipe, which opens into the first raw water tank 3.

Also, the end of the overflow pipe 19 of the first raw water tank 3 is connected to the raw water tank 30.
Open to.

Next, the operation of the liquid filtration device of the present invention will be explained.

Raw water that requires filtration treatment, such as factory wastewater, is stored in raw water tank 3.
The raw water is stored at 0, the pressure is increased by the raw water pump 32, and the raw water is supplied to the first raw water tank 3 via the raw water pipe 33.

In the first raw water tank 3, the raw water flows from the outer peripheral surface of the rotating filter 1 through the sulin (15.16) of the f-cloth IL water conduit pipe 31 due to the water head difference H1 with the second raw water tank 4. 4
leaks to.

In this case, the long fibers on the circumferential surface of the rotary filter 1, which is submerged in water and rotates slowly, are uniformly laid down by water pressure and rotational resistance, and as described above, the fiber length, number, diameter, material (Young A dense filtration layer is formed depending on the filtering rate), and suspended matter contained in the raw water adheres to the surface and undergoes the first stage filtration action.

Even in the second raw water tank 4, the water head pressure H with the overflow tank 13
The raw water that has undergone the first-stage flushing action due to the action of 2 flows out from the outer peripheral surface of the rotary filter body 2 to the overflow tank 13 via the p cloth 12 and the slits 1γ and 18 of the water conduit 31. Cloth 1
2, the filtered water is subjected to the filtration action of the second stage, and is discharged through the perfusion tank 13 and the discharge port 14.

In the example, two filtration device bodies are provided to perform a two-stage filtration action, but if necessary, other filtration device bodies may be arranged in series to provide space between adjacent raw water tanks. If a water head difference is formed between the two, further multistage filtration can be performed, and clear filtrate water is discharged from the discharge port 14.

FIG. 2 is a cross-sectional view showing a part of the back pressure washing hopper for removing floating matter (solid matter) attached to the P cloth.
It touches or is close to the long hairs of the r cloth 11 provided on the trunk of the body.

A hole 5b is opened in the center of the slide plate 11, and the long hairs that reach the hole 5b have no support, so that the water in the rotating baffle body 1 flows inward as shown by the arrow. It flows further outward.

In this embodiment, the backpressure washing hopper 5 is divided into upper and lower parts, and a throttle 5C is provided at the abutting portion of the backpressure washing hopper 5. This throttle 5c can be used to control the amount of backwash water or the number of rotating filters. It is used to balance the backwash water between.

The back pressure washing hopper 5 is supported by brackets 5d and 5e, and is supported by two points, the brackets 5d and 5e.
35.3 After moving the slide plate 5a up and down and changing the inclination angle and bringing the slide plate 5a into contact with the saw cloth 11,
6 to fix the position of the slide plate 5a.

FIG. 3 shows another shape of the back pressure washing hopper 5, in which a bracket 5f is supported on an inclined support base 5g so as to be movable in the direction of arrow A by a long hole button and bolts 41, 42. The above-mentioned back pressure washing hopper 5 is installed on 5f.
The vertical position and inclination angle of the slide plate 5a can be changed by inserting and tightening a bolt 51 through a long hole provided in a positioning plate 5h provided in the slide plate 5a.

When using the above-mentioned device, please use the following method according to the thickness of the fabric.
41 and 42 to adjust the vertical position of the bracket) 5f, further loosen the bolt 51 to change the mounting angle of the positioning plate 5h, and rotate it around part A to adjust the direction of the slide plate 5a.

By adjusting the position and orientation of the slide plate 5a in this way, it is possible to prevent a large amount of raw water from flowing into the back pressure washing hopper 5.

As mentioned above, the washing water flows out into the back pressure washing hopper by the water head pressure of the filtered water of the rotating filter, but when backwashing is performed in this way, when the long hair fibers become hanging down, the washing water is washed out. It is completely washed and dissolved into the hopper 5.6.

This cleaning action is performed automatically and continuously as the rotary filter bodies 1 and 2 rotate.

As mentioned above, the transient properties of r-cloth 11 and 12 can be adjusted by changing the length, number, diameter, and material (Young's modulus) of the fibers. The amount of particles is about 15 ppm when processed normally, but it changes to 200 to 11,000 ppm during carryover, and the number and size of particles has a wide distribution.

In such a case, a single rotating filter will immediately become clogged and it will be impossible to maintain the amount of filtrated water, but in the multi-stage filtration device of the present invention, for example, the length of the fibers in each cloth 11 can be shortened and the number of fibers can be reduced. By appropriately combining factors that cause the filter to become coarse, such as a material with a large diameter and a high Young's modulus, we can filter suspended solids with large particles without increasing water flow resistance. In step 12, the length of the fiber is increased, for example,
By using a large number of filters, a small diameter filter, and a low Young's modulus, a fine filter can be created to filter suspended matter with small particle diameters.

In addition, the cleaning effect and the degree of fiber lodging, that is, the filtration characteristics, can be changed not only by the fabric manufacturing conditions but also by the water head difference and the rotation speed of the rotating drum. This can be done with an extremely high degree of freedom.

As mentioned above, since multiple filtration device bodies are arranged in series, the number of arrays can be selected appropriately depending on the composition and amount of suspended matter in the raw water and the degree of eutrophication of the raw water. can.

In addition, by selecting the pile length and basis weight of the fibers flocked to the base fabric, the filtration characteristics of the r-cloth can be adapted to handle various floating substances in raw water. It can be used to filter large floating particles first, and then to filter fine floating particles by making the fibers longer and having a higher basis weight.

Furthermore, since a water head difference is formed between the main bodies of the filter, the filtrate can be sequentially, continuously, and automatically supplied to the next water tank.

Furthermore, in the present invention, the backwashing hopper is equipped with a throttle, so the amount of backwashing water can be controlled.

Alternatively, since the back pressure washing hopper is provided with means for adjusting the vertical and inclination of the slide plate, it is possible to prevent a large amount of untreated raw water from flowing into the filtered water.

By adjusting the hopper's aperture and slide plate adjustment means according to the type of floating matter, the hair length and basis weight of the plant fibers, the filtration efficiency can be further increased, and it is possible to easily obtain a volume of filtrated water of a certain quality or higher at all times. .

- Furthermore, since the present invention does not require any special equipment for transporting the filtrate or removing the filtrate, it is possible to obtain a small and economical filtration device.

[Brief explanation of drawings]

FIG. 1 is a side sectional view showing the main parts of a liquid filtration device according to an embodiment of the present invention, and FIGS. 2 and 3 are sectional views showing the main parts of a part of a back pressure washing hopper. 1.2: Rotating filter body, 3... First raw water tank, 4...
・Second raw water tank, 5, 6... Back pressure washing hopper, 7, 8
... Water pipe, 11, 12... P cloth, 19, 23.
...Water level setting pipe, 24...Overflow weir plate, 25...Overflow pipe.

Claims (1)

[Scope of utility model registration request] Fibers with pile length of 20 to 801nrI& have a basis weight of 400 to 10.
The main body of the filtration device is made up of a filter body made of R cloth, which is flocked to a base fabric of 009/m2, stretched over the outer circumferential surface of a drum-shaped cage, which is rotatably supported on a hollow shaft, and which is submerged in a water tank. A plurality of filters are arranged in series, and a water head difference is sequentially formed between adjacent filtration device bodies, so that the filtrate from the hollow shaft is sequentially supplied into the water tank of the next filtration device body. , and below the filter body, a hopper having a slide plate with an opening in contact with the filter body attached to the upper part is attached and connected to the drain pipe, and the hopper is supported at at least two places to prevent the hopper from discharging. A multi-stage liquid swelling device characterized by being able to freely change the vertical direction and inclination.