JPH0568286B2 - - Google Patents

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention is applicable to suspended solids contained in surface water, coagulation-sedimentation treated water, biologically treated water, process water, washing wastewater, liquids containing dissolved valuables, etc. The present invention relates to a filtration device used to efficiently filter .

<Prior art> Conventionally, when filtering suspended solids contained in various liquids to obtain a clear filtrate, filter devices filled with layers of granular materials such as sand or anthracite, or ceramics or sintered materials have been used. Candle filters that directly filter with a cylindrical filter body made of metal, etc., and precoat filters that precoat various filter aids on the filter body are used.

<Problems to be Solved by the Invention> However, conventional filtration devices have drawbacks in that the operation for cleaning clogged filter media is complicated and a large amount of cleaning fluid is generated.
Conventional filtration devices also have the disadvantage of relatively high equipment costs.

The present invention solves the drawbacks of conventional filtration devices, and aims to provide a filtration device that has a relatively simple structure, is easy to operate, generates extremely little cleaning waste fluid, and has low equipment costs. purpose.

<Means for Solving the Problems> The present invention incorporates a spherical or cylindrical cleaning body having a diameter slightly smaller than the inner diameter of the filter cloth cylinder in a relatively long water-permeable hose-like filter cloth cylinder, and further It has a structure in which the inlet for the liquid to be treated and the outlet for the concentrated liquid are connected to the end of the filter cloth tube, and the liquid to be treated containing suspended matter is communicated to one end of the filter cloth tube. The cleaning body is first moved to the other end of the filter cloth cylinder by the inflow pressure, and the press-fit is continued to trap suspended matter in the liquid on the inner surface of the filter cloth cylinder, Filtered water is obtained from the outer surface of the filter cloth tube, and if the pressure loss of the filter cloth tube increases due to continued filtration, the filtration operation is interrupted and the liquid to be treated or clean water is discharged from the other end of the filter cloth tube. The cleaning body is moved from the other end of the filter cloth cylinder to one end by the inflow pressure, and the suspended solids adhering to the inner surface of the filter cloth cylinder are scraped off by the cleaning body, and the concentrated liquid of suspended solids is removed from the filter cloth cylinder. The present invention relates to a filtration device that discharges water from an outlet.

The present invention will be explained in detail below based on the drawings.

FIG. 1 is an explanatory diagram of a flow showing an example of an embodiment of the present invention, and in the figure, 1 is a hose-shaped filter cloth cylinder. The filter cloth cylinder 1 is made of natural fibers or synthetic fibers woven or knitted into a hose shape, and its diameter varies from 20 to 200 mm depending on the processing amount and installation location.
Further, its length can be arbitrarily designed to be 1 m to several meters. Further, inside the filter cloth tube 1, a cylindrical cleaning body 12 made of a material such as synthetic resin, hard rubber, ceramics, wood, or metal is built in, and has a diameter slightly smaller than the inner diameter of the filter cloth tube 1. Also, filter cloth cylinder 1
Fittings 2 are provided at both ends of the pipe 2, and both ends of the raw water inflow pipe 4 are communicated with both fittings 2 via valves 3A and 3B.

Further, a raw water supply pipe 6 is branched and communicated with the raw water inflow pipe 4 via a pump 5.

Furthermore, both ends of the concentrate outflow pipe 8 are branched and communicated with the raw water inflow pipe 4 via valves 7A and 7B,
A discharge pipe 9 is branched and communicated with the concentrate outflow pipe 8 . 10 is a receiving pan, and a filtrate water outflow pipe 11 is communicated with the receiving pan 10. Note that 13 is a pressure gauge.

<Operation> The filtration operation in this embodiment is as follows.

First, the valves 3A and 7B are opened, and the pump 5 is driven to force raw water into the filter cloth cylinder 1 through the raw water supply pipe 6 and the raw water inlet pipe 4 at an arbitrary pressure of 0.1 to 10 kg/cm ² . The cleaning body 12 moves to the right side due to the press-in of the raw water and stops when it comes into contact with the fitting 2, but when this state is reached, only the valve 7B is closed and the press-in of the raw water continues. Note that when the cleaning body 12 comes into contact with the fitting 2, the raw water supply pipe 6,
As the pressure in the system inside the raw water inlet pipe 4 and the filter cloth cylinder 1 increases, the increase in pressure may be detected by the pressure gauge 13 and the timing for closing the valve 7B may be determined based on this, or alternatively, a timer may be used. There is no problem even if valve 7B is closed. Further, if the structure is such that one outlet of the filter cloth cylinder 1 can be closed by contact between the cleaning body 12 and the joint fitting 2, there is no need to close the valve 7B during filtration.

Through such press-fitting, suspended solids in the raw water are captured by the inner surface of the filter cloth tube 1, and filtrate water obtained from the outer surface of the filter cloth tube 1 is collected by the receiving pan 10 and flows out from the filtrate outflow pipe 11.

Note that during the first cycle of operation, a thin cake layer of suspended solids, which will be described later, is not formed on the inner surface of the filter cloth cylinder 1, so some of the suspended solids may leak out from the filter cloth cylinder 1. In such a case, a thin cake layer is formed on the inner surface of the filter cloth cylinder 1 by circulating the filtered water to the raw water to some extent, and the circulation of the filtered water is stopped when clear filtered water is obtained by forming the cake layer. Good.

Furthermore, if the suspended matter contained in the raw water is very fine, a flocculant may be added to the raw water in advance and stirred to form micro flocs, which may then be filtered.

When such filtration is continued, the suspended matter adheres to the inner surface of the filter cloth cylinder 1 in the form of a cake, and its thickness gradually increases. As a result, pressure loss increases and filtration flow rate decreases.

When such a state occurs, the cleaning described below is performed.

That is, close the valve 3A, and if the valve 7B is open, close the valve 7B, open the valve 3B and the valve 7A, and then press the raw water in from the opposite direction to apply water pressure to the cleaning body 12 moving to the right side. to move it to the left. As the cleaning body 12 moves, as shown in FIG. has a diameter slightly smaller than the inner diameter of the filter cloth tube 1, so that after the cleaning body 12 moves, a very thin cake layer 14B corresponding to the difference between the inner diameter of the filter cloth tube 1 and the diameter of the cleaning body 12 is formed. remains on the inner surface of the filter cloth cylinder 1.

On the other hand, most of the suspended solids scraped off by the cleaning body 12, together with the raw water remaining in the filter cloth cylinder 1, become a concentrated liquid of suspended solids, and the concentrated liquid flows through the concentrated liquid outflow pipe 8 and the discharge pipe 9. It is leaked through.

Note that the scraped suspended matter adheres to the cleaning body 12 to some extent, but a small through hole is provided in the cleaning body 12,
When the cake layer 14A of suspended solids is scraped off by the cleaning body 12, the water in one filter cloth cylinder 1 separated by the cleaning body 12 can be jetted from the through hole into the other filter cloth cylinder 1. . By providing the through-hole in the cleaning body 12 in this manner, suspended matter can be effectively drained.

When the cleaning body 12 comes into contact with the left joint fitting 2 due to the press-in of raw water from the valve 3B, the valve 7A is closed, and the press-in of the raw water is continued to continue filtration.

Through this operation, suspended solids in the raw water are cake-filtered by the cake layer 14B left on the inner surface of the filter cloth tube 1, so the same effect as pre-coat filtration is achieved, and clear filtered water is filtered from the beginning of filtration. Obtained from the outer surface of the cloth tube 1. Further, when the thickness of the cake layer increases due to such filtration, the flow path is reversed and cleaning is performed as described above.

By alternately introducing raw water from the left and right sides of the filter cloth cylinder 1 in this manner, filtration can be performed without interruption.

Note that when moving the cleaning body 12 to scrape off the cake layer 14A formed on the inner surface of the filter cloth cylinder 1, fresh water may be forced in instead of raw water.

The diameter of the cleaning body 12 used in the present invention is slightly smaller than the inner diameter of the filter cloth cylinder 1.
The closer the diameter is to the inner diameter of the filter cloth cylinder 1, the more the remaining cake layer 14 as shown in FIG.
This is not preferable because the thickness of B becomes thinner, making it impossible to achieve the purpose of obtaining clear filtered water immediately after the start of filtration. Also, if the diameter is too small compared to the inner diameter of the filter cloth cylinder 1, water pressure will cause the cleaning body 12 to
When the cleaning body 12 is moved within the filter cloth cylinder 1, water escapes from around the cleaning body 12, which hinders the movement of the cleaning body 12 using water pressure. Therefore, cleaning body 1
The diameter of filter cloth cylinder 2 is naturally determined by the above two reasons, but it is usually preferable to make the diameter of cleaning body 12 smaller than the inner diameter of filter cloth cylinder 1 by about 1 mm to several mm.

Although the cleaning body 12 shown in FIGS. 1 and 2 has a cylindrical shape, the cleaning body 12 is not limited to a cylindrical shape, and may be spherical.

FIG. 3 is an explanatory diagram showing the flow of another embodiment of the present invention, in which a large number of filter cloth cylinders 1 are arranged vertically.

In the present invention, it is possible to use a large number of filter cloth cylinders 1 as described above, and it is also possible to arrange them vertically, and when performing filtration in FIG.
As shown in the figure, open the valves 3A and 7B to force the raw water into each filter cloth cylinder 1 in an upward flow, and
is brought into contact with the upper fitting fitting 2, then the valve 7B is closed and the injection of raw water is continued to remove suspended solids from each filter cloth cylinder 1.
The filtered water is captured on the inner surface of each filter cloth cylinder 1, and filtered water is obtained from the outer surface of each filter cloth cylinder 1.

Furthermore, if the pressure loss increases due to such filtration, close the valve 3A and open the valves 3B and 7A to allow the raw water to flow downward, and each cleaning body 1
2 is moved downward to scrape off the cake layer 14A formed on the inner surface of each filter cloth cylinder 1, and the concentrated liquid of suspended matter is discharged from the discharge pipe 9.

<Effects> The greatest advantage of the present invention is that the amount of cleaning wastewater is extremely small.

That is, after the filtration is completed, the cleaning body 12 is removed from the filter cloth cylinder 1.
Move the filter cloth cylinder 1 from one end to the other end using water pressure.
The cake layer 14A formed on the inner surface is scraped off by the cleaning body 12 to discharge a concentrated solution of suspended solids, but the amount of concentrated solution discharged at this time is an amount corresponding to the internal volume of the filter cloth cylinder 1. This is extremely rare. In the filtration device of the present invention, the solid matter concentration is usually several thousand to several tens of thousands.
mg/concentrate is obtained. Such a concentrated solution of concentrated suspended matter cannot be obtained using conventional filtration devices such as sand filtration devices and candle filters. Furthermore, since an extremely thin cake layer 14B can be formed after most of the cake layer 14A is scraped off by moving the cleaning body 12, cake filtration is possible, and suspended solids contained in the raw water can be removed. Even if the water is relatively fine, clear filtered water can be obtained immediately after filtration.

The filtration device of the present invention can also be used as a concentrator for various types of sludge water that have a relatively high content of suspended solids, such as those generated from coagulation sedimentation devices and biological treatment devices, and can be used to produce concentrated liquids with extremely high concentration ratios. can be obtained.

As is clear from the above detailed explanation, the filtration device of the present invention does not require special washing water, the washing operation is simple, the amount of washing wastewater is small, and its concentration is high, compared to the conventional method that required a sedimentation step. Even raw water with a high content of suspended solids can be directly filtered without performing a sedimentation process, and by switching the direction of press-feeding into the filter cloth cylinder, filtration is not interrupted during cleaning, so-called continuous filtration is possible. It can be said that it is a filtration device with extremely high operating efficiency. In addition, the filtration medium used in this filtration device is a filter cloth tube, and the opening, diameter, length, and number of the filter cloth tubes can be freely selected according to the properties of the liquid to be treated and the amount to be processed. It is possible to manufacture an optimal device depending on the properties of the processing liquid and the processing amount. Furthermore, the filter cloth tube and cleaning body used in the present invention are extremely inexpensive, can filter only with the pressure force of a pump, do not require special maintenance, and have lower initial and running costs than conventional devices. can be significantly reduced.

[Brief explanation of the drawing]

The drawings all show embodiments of the present invention, and the first
The figure is an explanatory diagram of a flow showing an example of the embodiment, FIG. 2 is a sectional view showing how the cleaning body built in the filter cloth cylinder moves, and FIG. 3 is a diagram showing another embodiment of the present invention. It is an explanatory diagram of a flow showing. 1...Filter cloth tube, 2...Joint fittings, 3...Valve, 4
... Raw water inflow pipe, 5 ... Pump, 6 ... Raw water supply pipe, 7 ... Valve, 8 ... Concentrate outflow pipe, 9 ... Discharge pipe, 10 ... Receiving pan, 11 ... Filtered water outflow pipe ,
12... Cleaning body, 13... Pressure gauge, 14... Cake layer.

Claims (1)

[Claims] 1 A spherical or cylindrical cleaning body having a diameter slightly smaller than the inner diameter of the filter cloth tube is built into the hose-like filter cloth tube, and an inlet for the liquid to be treated and a concentration port are provided at the end of the filter cloth tube. By communicating the liquid outlet and pressurizing the liquid to be treated containing suspended solids through the inlet, the suspended solids are captured on the inner surface of the filter cloth cylinder and the filtrate is obtained from the outer surface of the filter cloth cylinder, Further, the cleaning body is moved from one end of the filter cloth cylinder to the other end by hydraulic pressure, and the cleaning body scrapes off the suspended solids adhering to the inner surface of the filter cloth cylinder, and the concentrated liquid of suspended solids is discharged from the outlet. A filtration device characterized by: