JPH03224609A - Method and device for filtration of liquid - Google Patents

Abstract

PURPOSE:To backwash filter medium at any time without stopping all the filter units and to improve the efficiencies of filtration and backwashing by carrying out filtration in one system group and backwashing in another system group and alternatively changing over these system groups. CONSTITUTION:Filthy liquid A is filtered in a filter 1a of one system group (a), and the filter medium 2b of a filter (b) is backwashed in the filter (b) of another system group (b); consequently, the filter medium 2b of the filter (b) which is not used for filtration is not almost clogged as backwashing is carried out. The filtration of filthy liquid A and the backwashing of filter mediums 2a, 2b in the system group (a), (b) are suitably changed over, and when the timing of this change-over is shortened, the filter mediums 2a, 2b are backwashed in the period in which the sticking amount on the filter mediums 2a, 2b is small and the clogging of the filter mediums 2a, 2b is less occurred with the result that the regeneration recovery rate of the filter medium 2a, 2b is not almost lowered.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention is applicable to the filtration of water-based and oil-based liquids in general; The present invention relates to a liquid filtration device used in various fields to filter machining fluids and lubricating fluids used in special machining such as electrical discharge machining, plastic processing such as rolling, forging and drawing, and the like.

(Prior Art) Conventionally, methods for separating a soiled liquid mixed with dust (for example, processed wood chips) into dust and liquid include: (1) A method in which a dirty liquid is subjected to an appropriate operation to separate it into dust and liquid.

(2) A method in which only dirt is removed using a filter material with pores such as a net, paper, or cloth.

It is broadly divided into

The device used in the former method is generally called a separation device, and the device used in the latter method is generally called a filtration device.

The separation apparatus includes a magnetic type in which magnetic dust is attracted to a magnetized metal drum or the like, and a centrifugal type in which a filtrate and dust are separated using centrifugal force. Separation devices also include devices that aggregate dust using a filter aid and remove it by sedimentation.

Although such a separation device has the advantage of requiring few consumables, it has the drawbacks of low separation accuracy and low throughput.

In addition, since the amount of non-magnetic dust such as aluminum, titanium, and ceramics has increased rapidly in recent years, there is also the problem that it cannot be picked up by magnetic types.

On the other hand, the latter type of filtration device is a natural filtration type in which the dirty liquid A is passed through a sheet-shaped filtering material G to be filtered as shown in Fig. There are vacuum filtration types that use vacuum (vacuum) to force filtration. Furthermore, the filter media can be made into disc type, cartridge type,
There is also a pressure filtration type in which the filter is formed into a bag shape and set in a closed container, and the soiled liquid is filtered by applying pressure within the container. At this time, some filter media are coated with silica clay or the like to make the mesh size finer, thereby achieving high filtration accuracy.

Incidentally, as shown in FIG. 12, the cartridge type filter material G is formed by wrapping a perforated bobbin H, a cylindrical spring, etc. with a filter cloth or the like. Recently, some have been made by wrapping electric wire around a perforated bobbin.

(Problem to be Solved by the Invention) However, since filter media are originally intended to filter only liquid by adhering dirt, if the amount of dirt adhering exceeds a certain limit, the filter media will become clogged. The filtration flow rate (discharge rate) of the filtrate decreases rapidly, and the dirty liquid before filtration overflows outside the filtration device, and the supply of the filtrate to the machine body becomes insufficient.

Therefore, countermeasures when the filter material becomes clogged include replacing the filter material, scraping off the adhering dirt with a scraper, or applying vibration or shock to the filter material using ultrasonic waves, blows, pie breaks, etc. The 12th
As shown in Fig. 13, air or cleaning liquid C is sprayed on the clogged part of the filter medium G from the direction opposite to the flow of the dirt liquid to backwash the adhered dirt and remove the filter medium G. Among these measures that require regeneration and recovery, the method of replacing the filter material every time it becomes clogged wastes the filter material and is uneconomical.

Furthermore, when scraping with a scraper or the like, dirt may be pressed against the filter material during scraping, and the filter material may become clogged.

In addition, in order to backwash the filter material, it is necessary to relieve the pressure (liquid) inside the filter cylinder.To do this, in conventional technology, filtration must be stopped and the liquid inside the cylinder must be drained, or the backwash circuit must be removed. is installed separately from the filtration circuit, and backwashing must be performed using air or backwashing liquid. Therefore, if the filtration medium is heavily contaminated, the filtration device will stop for a long time, as shown by the broken line in Figure 9. It was sometimes longer and was less workable.

In addition, in order to minimize the downtime of the filtration device, if the filter material is not backwashed until it becomes clogged, the amount of filtered filtrate discharged will decrease as shown by the broken line in Figure 9. However, the fluctuation range is large, making it impossible to obtain a stable discharge amount.6Furthermore, in order to minimize the downtime of the filtration device, backwashing is performed after the filtration material becomes clogged.
If backwashing is completed in a short time, the regeneration recovery rate of the filter medium will be poor as shown by the broken line in FIG. 10, and the filter medium will rapidly become clogged, making it impossible to withstand long-term use.

In addition, in order to automatically perform backwashing with conventional filtration devices, it is necessary to separately provide supply and discharge circuits for the air and cleaning liquid, making the mechanism complicated, large-scale, and expensive. Become. Furthermore, when backwashing a cartridge-type filter material G as shown in FIG. 13, for example, the dirt removed by backwashing accumulates at the bottom of the filter.
How to deal with this filth is complicated, and normally it is not possible to automatically discharge the filth, and once a certain amount of filth has accumulated, the equipment must be stopped and the filth must be removed manually. I had to.

In order to alleviate these problems, it is possible to install a separation device before the filtration device, and use the separation device to remove most of the dirt, thereby reducing the amount of dirt that adheres to the filter material of the filtration device. Conceivable.

However, conventional separation devices are themselves complex, large-scale, expensive, and require a large footprint. Combining these conventional separation and filtration devices becomes increasingly expensive and bulky, takes up space to install, and has large dead zones.

(Object of the Invention) The object of the present invention is to solve the above-mentioned problems by using two or more filters and filtering the dirty liquid with one of the filters without using any other force such as air. To provide a liquid filtration method and an apparatus thereof, which can backwash the filter medium of the other filter to prevent clogging, ensure a stable amount of filtrate, and easily and automatically discharge dirt removed from the filter medium. It's about doing.

(Means for Solving the Problems) The liquid filtration method according to claim 1 of the present invention is shown in FIGS.
As shown in the figure, among two systems a and b in which filters 1a and 1b are installed, a dirty liquid A is supplied to the filter 1a of one system a, and the same dirty liquid A is filtered, and the other system System line filter 1
filtrate B filtered by the filter 1a of the system a;
A part of the filter is supplied as cleaning fiC, and the cleaning liquid C is used to backwash the dirt adhering to the filter medium 2b of the filter 1b (washing the filter medium by flowing the cleaning liquid from the direction opposite to the dirty liquid). The system is characterized in that filtration and backwashing in both the systems a and b are switched at appropriate times.

In the liquid filtration method according to the second aspect of the present invention, as shown in FIG.
a, 2b from the bottom to the top and filter the washing liquid C.
is flowed downward from above the filter media 2a, 2b of the filters 1a, 1b to remove the dirt I attached to the filter media 2a, 2b.
I) '15 It is characterized by backwashing so as to cause it to fall and settle.

A liquid filtration method according to a third aspect of the present invention is such that the backwashed liquid R that has backwashed the filter 1b is returned to the inlet side of the liquid suction pump 19 that pumps up the dirty liquid in the dirty liquid tank 18. It is characterized by the fact that

The liquid filtration device according to the fourth aspect of the present invention, as shown in FIG. , supply lines 3a and 3b that supply dirty liquid A to both lines a and b, dirty liquid switchers 5a and 5b that switch the supply of dirty liquid A to the same supply lines 3a and 3b, and both filters. filtrate discharge systems 6a and 6b that discharge the filtrate B filtered through the filters 1a and 1b to the outside of both filters 1a and 1b; A cleaning liquid supply line 7 which supplies part of the liquid B to the other filters 1b and 1a as the cleaning liquid C, and a cleaning liquid C to the same supply line 7.
It is characterized by comprising cleaning liquid switching devices 8a and 8b for switching the supply of cleaning liquid.

As shown in FIG. 5a, a liquid filtration device according to a fifth aspect of the present invention has a structure in which, as shown in FIG. This filter is characterized in that the peripheral edges of the filter media 2a and 2b are clamped and fixed.

As shown in FIG. 1, a liquid filtration device according to a sixth aspect of the present invention is provided between the cleaning liquid switching devices 8a, 8b and the water supply pump 19, and a backwashed liquid that has backwashed the filter 1b or 1a. R
Reduction lines 12a and 1 return the liquid to the inlet side of the liquid suction pump 19.
2b is provided.

According to a seventh aspect of the present invention, the liquid filtration device has the dual path a.
, b are provided with coarse separators 9a and 9b in front of the filters 1a and 1b (FIG. 11), respectively, for separating bulky waste E (FIG. 3) with a large specific gravity from the dirty liquid A. .

A liquid filtration device according to an eighth aspect of the present invention is characterized in that, as shown in FIG. 2, one or more of the filters 1a and 1b are connected after each of the coarse separation devices 9a and 9b. be.

A liquid filtration device according to a ninth aspect of the present invention, as shown in FIG. 4, shares the two coarse separation devices 9a and 9b as one,
The apparatus is characterized in that the filters 1a and 1b of the two routes a and b are connected after one of the crude separators 9a (9b).

The liquid filtration device according to claim 10 of the present invention is shown in FIG. 11a.
, as shown in Figure 11, is characterized in that a plurality of filters 1a and 1b are mounted above one or both of the rough separation devices 9a and 9b.

In the liquid filtration device according to claim 1-1 of the present invention, a precipitate F (fourth
The apparatus is characterized in that it is provided with sediment discharging devices 1Oa and 1Ob (FIGS. 1 to 3) for discharging the water (see FIGS. 1 to 3).

A liquid filtration device according to a twelfth aspect of the present invention is, as shown in FIG.
b.

In a liquid filtration device according to a thirteenth aspect of the present invention, as shown in FIG. This is characterized in that the switching is performed later than the switching of the cleaning liquid switching devices 8a and 8b which switch the supply of the cleaning liquid C to the supply line 7.

A liquid filtration device according to a fourteenth aspect of the present invention, as shown in FIG.
filtrate discharge lines 6a and 6b that discharge the water to the fresh water tank 46
Check valves 47a and 47b which normally prevent the discharged filtrate B from flowing into the respective valves 47a and 47b crack and allow the filtrate B to flow in when the filtrate B exceeds a certain pressure.
It is characterized by having the following.

(Function) In the liquid filtration method of claim 1 of the present invention, FIG.
As shown in Fig. 2, the dirty liquid A is filtered in the filter 1a of one system path a, and the filter medium 2b of the same filter 1b is backwashed in the filter 1b of the other system path. The filter medium 2b of the filter 1b which is not used for this purpose is backwashed during this period, so that it hardly becomes clogged.Moreover, the filtration of the dirty liquid A in both the systems a and b and the backwashing of the filter mediums 2a and 2b are performed. Since the switch can be made in a timely manner, if the timing of this switch is shortened, the filter media 2a, 2b will be backwashed while the amount of dirt adhering to the filter media 2a, 2b is small, and the filter media 2a, 2b will be further cleaned. It becomes difficult to clog, and as shown by the solid line in FIG. 10, the regeneration recovery rate of the filter media 2a and 2b hardly decreases. Since it is used as cleaning liquid C, there is no need to separately prepare air or liquid for cleaning, which is convenient.

In the liquid filtration method according to the second aspect of the present invention, the dirty liquid A is flowed upward from below the filter media 2a, 2b as shown in FIG. .

Also, as shown in FIG. 3, since the cleaning liquid C is flowed downward from above the filter media 2a, 2b for backwashing, the filter media 2a, 2b
The dirt adhering to the lower surface is easily peeled off.The peeled dirt falls down and settles below the filters 1a and 1b, and the accumulated sediment F is discharged from the sediment discharge port 20 in a timely manner. Ru.

In the liquid filtration method of the third aspect of the present invention, the backwashed liquid R that has backwashed the filter 31b is returned to the inlet side of the liquid suction pump 19 that pumps up the dirty liquid in the dirty liquid tank 18.
The backwashed liquid R is not discharged to the outside of the filtration system, but is circulated and effectively utilized. Moreover, since the backwashed liquid R is not discharged to the outside of the filtration system, there is no need to separately process the backwashed liquid R outside.

In the liquid filtration apparatus according to the fourth aspect of the present invention, similarly to the first aspect of the present invention, it is possible to perform filtration with one filter and backwash the filter medium with the other filter at the same time. In addition, there are dirty liquid switching devices 5a and 5b that automatically switch the supply of dirty liquid A to the two systems a and b, and a cleaning liquid switch that automatically switches the supply of cleaning liquid C to the two systems a and b. 8a
, 8b, the filtration and backwashing of the two systems a and b are automatically switched and operated automatically at the appropriate time.

In the liquid filtration device of the fifth aspect of the present invention, the periphery of the filter media 2a, 2b is located between the receiving edge 21a protruding to the outer periphery of the container 21 of the filters 1a, 1b and the holding part 31a of the canopy 31. Since it is clamped and fixed, the filter material 2a,
The filtration area of 2b can be increased, and the filtration efficiency is improved. Incidentally, when the inner diameter of the container 21 is the same, when the peripheral edges of the filter media 2a, 2b are attached inside the container 21, the filtration area of the filter media 2a, 2b becomes narrower by that much, and the filtration efficiency decreases.

In the liquid filtration device according to the sixth aspect of the present invention, a backwashed liquid R obtained by backwashing the filter 1b or 1a is provided between the cleaning liquid switching devices 8a, 8b and the water supply pump 19 according to the fourth aspect. Reduction lines 12a and 12b that return to the inlet side of the liquid suction pump 19
, the backwashed liquid R can be circulated and used effectively without being discharged to the outside of the filtration system. Moreover, since the backwashed liquid R is not discharged to the outside of the filtration system, there is no need to separately process the dirty liquid A outside.

In the liquid filtration device according to claim 7 of the present invention, the coarse waste E in the dirty liquid A is separated by the coarse separators 9a and 9b and settles to the bottom of the devices 9a and 9b, as shown in FIG. ,
Almost no coarse waste E flows toward the filter media 2a and 2b.
Therefore, the dirty liquid A is easily filtered by the filters 1a and 1b.

In addition, the coarse garbage D peeled off by backwashing is collected in the coarse separator 9a.
, 9b has a structure that tends to settle at the bottom of the filter 1b, so the backwashed liquid R does not contain the coarse garbage D, and the circulation 1 (filtration-stripping-filtration) of the coarse garbage D does not require backwashing of the filter 1b. Even if the backwashed liquid R is returned and circulated to the inlet side of the liquid suction pump 19 that pumps up the dirty liquid in the dirty liquid tank 18, the liquid suction pump 19 will not be clogged with coarse garbage or malfunction. This eliminates the discharge of backwash liquid from the system, which was the biggest drawback of conventional filtration-backwashing, alternating switching filtration that alternates between backwash and filtration.
Continuous filtration and backwashing is now possible. In the liquid filtration apparatus according to claim 8 of the present invention, one or more filters 1a, 1b are attached to each coarse separator 9a, 91) as shown in FIG. Tea, 9b and filters 1a, 1b can be used as a set, simplifying the configuration of piping, etc.

In the liquid filtration apparatus according to the ninth aspect of the present invention, as shown in FIG.
b are connected, so the installation space is not taken up and the processing capacity is improved.

In the liquid filtration apparatus according to claim 10 of the present invention, above one or both of the coarse separation apparatuses 9a and 9b, as shown in FIG.
, as shown in Figure 13? ! Since several filters 1a and 1b are mounted, even if the number of filters 1a and 1b increases, there is no need to secure a special installation space for them, and the installation area of the liquid filtration device is small.

In the liquid filtration apparatus according to claims 11 and 12 of the present invention, as shown in FIGS. In the liquid filtration device according to claim 13 of the present invention, soil liquid can be automatically discharged by the sediment discharge devices 110a, 1oblLa, and 11b, respectively. Since the switching between the cleaning liquid switching devices 5a and 5b is performed later than the switching between the cleaning liquid switching devices 8a and 8b, which switches the supply of the cleaning liquid C to the cleaning liquid supply line 7, for example,
While the dirty liquid switch 5a on the filter 1a side of the system is still open and the dirty liquid switch 5b on the filter Ib side of the system is still closed, the cleaning liquid switch 8b, which had been open until then, is closed. (At this time, the cleaning liquid switching device 8a remains closed.) Until the dirty liquid switching devices 5a and 5b are switched between opening and closing, the filtrate B continues to be discharged from one of the filters 1a, and the same filtrate B fills the filter 1b.

For this reason, even if the dirty liquid switch 5a is subsequently switched to close and the dirty liquid switch 5b is switched to open, the filtrate B will not be interrupted from the filter 1b (discharged, and at the same time the filter 1a
can also be backwashed immediately.

A liquid filtration device according to a fourteenth aspect of the present invention includes a filter 1
The filtrate discharge lines 6a and 6b, which discharge the filtrate B filtered by the filters a and 1b into the fresh water tank 46, have the same filtrate B, although the inflow of the filtrate B that is normally discharged is blocked. Check valves 47a and 47b are provided that crack when the pressure exceeds the pressure and allow the filtrate B to flow in.
The filter medium 2a or 2b shown in the figure is backwashed, and the cleaning liquid switching device 8
Backwashed liquid R passes through a or 8b and returns to the water supply pump 19
When the amount of water becomes too large to pass through the cleaning liquid switch 8a or 8b, the cleaning liquid B for backwashing the filter medium 2a or 2b cracks the check valve 47a or 47b and
Sent out on 6th.

Therefore, even if the amount of backwashed liquid R that passes through the cleaning liquid switch 8a or 8b and returns to the water supply pump 19 increases so that it cannot pass through the cleaning liquid switch 8a or 8b, the backwashed liquid R or the filtration The cleaning liquid B for backwashing the material 2a does not overflow.

(The following is a blank space) (Example) Figures 1 and 3 show an example of the liquid filtration method and apparatus of the present invention.

In these figures, 1al and 1b are filters installed in two systems a and b, respectively, and 9a and 9b are filters installed below the containers of the filters 1a and 1b, respectively. It is a separation device. The filters 1a and 1b are of the same construction and are of a sealed pressurized type, and the rough separation devices 9a and 9b are also of the same construction, and are all made of rust-resistant stainless steel 5US304 material.

The rough separation devices 9a and 9b have a dirt liquid supply port 22 provided on the peripheral wall 21 of the container to which the dirty liquid A is supplied, and a dirt liquid supply port 22 provided on the peripheral wall 21 of the container.
1 and a baffle plate 23 provided in parallel inside the supply port 2
a partition plate 24 that partitions the upper side of the baffle plate 23 and the peripheral wall 21 on the upper side of the baffle plate 2; and a shielding plate 25 installed vertically between the baffle plate 23 and the peripheral wall 21 on the side of the dirt liquid supply port 22; Inclined plate 2 installed with a gap 26 provided below the baffle plate 23
It consists of 7. In these rough separation devices 9a and 9b, as shown in FIG. According to the flow, bulky waste E with a large specific gravity slides down along the inclined plate 27 and settles from the opening 28 below. Furthermore, since the inclined plate 27 is formed to taper downward, the force of the swirling flow is accelerated, and even with highly viscous oil-based cutting fluid, the swirling flow has less momentum downward. Never. According to experiments conducted by the applicant, 40% or more of the coarse waste E in the soil liquid A was removed by the coarse separators 9a and 9b.

In this way, the dirty liquid A from which coarse waste E has been removed by the rough separators 9a and 9b is transferred to the baffle plate 23 and the inclined plate 2.
7 and rises to the filters 2a, 2b.

This dirty liquid A passes through filter media 2a and 2b set in the filters 1a and 1b from below to above, and at this time, the dirt in the dirty liquid A passes through the filter media 2a and 2b set in the filters 1a and 1b.

2. The filtrate B adheres to the bottom surface of the filter material 2 and is filtered.
a, 2b flows upward, and the top of the filters 1a, 1b tW31
The filtrate is discharged from the filtrate discharge port 32 of the filtrate.

The filter media 2a, 2b are formed into a spherical shape as shown in FIG. 3, and the hem thereof is fixed to a metal fixing ring 30. As clearly shown in FIG.
It is embedded in.

Moreover, an OIJ song 2.43 is interposed in each of the inner and outer grooves of the circumferential groove 41, and from above the OIJ song 2.43, the holding part 3 of the canopy 31 is inserted.
1a is covered, and this holding part 31a and the mounting tool 40
The fixing ring 30 is fixed to the fixture 40 by tightening with bolts and nuts, and the filter media 2a, 2b are set in the filters 1a, 1b.

A screen basket 44 is attached above the filter media 2a, 2b to prevent the filter media 2a, 2b from being pushed upward by the pressure of the dirty liquid A flowing upward and deforming or expanding too much. There is. As shown in FIG. 3, this screen bath plate 44 is made of punching metal in which a large number of holes are formed to connect the filter medium 2a.
, 2b is formed into a spherical shape. Further, the peripheral edge of the screen basket 44 is fixed to the inner lower end of the canopy 31 by welding or the like.

In addition, in the filters 1a and 1b, as shown in FIG. The cleaning liquid C is supplied into the filters 1a and ib through the liquid discharge port 32 in a direction opposite to that of the dirty liquid A. As a result, the filter media 2a and 2b have a spherical shape that swells downward, and the filter media 2
The cleaning liquid C that passes through the filter media 2a and 2b from top to bottom removes dirt adhering to the bottom surfaces of the filter media 2a and 2b.
It is meant to fall and settle downward.

Furthermore, a sediment discharge port 2o is provided at the lower end of the filters 1a and 1b to discharge the settled sediment F.

3a and 3b shown in FIGS. 1 and 3 are supply lines that supply the dirt tiA pumped up by the water supply pump 19 from the waste liquid tank 18 to the filters 1a and 1b of the two lines a and b. .

Reference numerals 5a and 5b shown in FIGS. 1 and 3 are dirty liquid switching devices for switching the dirty liquid A to the supply lines 3a and 3b. Electrically operated valves are used in the dirty liquid switching devices 5a and 5b.

6a and 6b shown in FIGS. 1 and 3 are the filters 1a and 1.
This is a filtrate discharge system that discharges the filtrate B filtered by b to the fresh water tank 46. This filtrate discharge system 6a, 6
Check valves 47a and 47b are attached to each of the check valves 47a and 47b, which crack at a certain pressure with respect to the pressure of the filtrate B discharged from the filtrate discharge ports 32 of the filters 1a and 1b.

7 shown in FIGS. 1 and 3 is a part of the filtrate B filtered through the filter 1a or ib of one of the two systems a and b, and used as the cleaning liquid C to clean the other system. This is a cleaning liquid supply line that supplies the cleaning liquid to the filter 1b or 1a.

Reference numerals 8a and 8b shown in FIGS. 1 and 3 are cleaning liquid switching devices for switching the cleaning liquid C to two paths a and b, and in this embodiment, an electric valve is used. This cleaning liquid switching device 8a
, 8b are connected to dirt liquid reduction system lines 12a and 12b,
The backwashing liquid R that has passed through the cleaning liquid switching devices 8a and 8b is configured to be returned to the inlet side of the water supply pump 19 through the same reduction system lines 12a and 12b.

Further, 10a and 10b are sediment discharge portions for discharging the sediment F settled at the bottom of the rough separators 9a and 9b. These precipitate discharge parts 10a and 10b are connected to the crude separators 9a and 9.
It is composed of a discharge line 51 that connects the sediment discharge port 20 provided at the bottom of the sludge box 50, and sediment discharge valves 52a and 52b.

The filtration apparatus of the present invention shown in FIGS. 1 to 3 is used in the following manner.

First, the operation of system path a and system path is performed by the dirty liquid switching device 5a.
, 5b, cleaning liquid switching devices 8a, 8b, and sediment discharge valves 52a, 52b are opened and closed. When the dirty liquid A from the dirty liquid tank 18 is supplied by the water supply pump 19, the dirty liquid switch 5a of the system path a, the cleaning liquid switch i8b of the system path, and the sediment discharge valve 52b are opened.
The dirty liquid switching device 5b in the system path, the cleaning liquid switching device 8a in the system path a, and the sediment discharge valve 52a are closed, and as a result, of the two filters 1a and 1b, the filter 1a in the system path a is switched to the dirty liquid. In the filtration state in which A is filtered, the filter 1b in the system goes into the backwashing state.

Incidentally, the amount of the dirty liquid A supplied to the filter 1a of the one system path a may be adjusted by a flow rate adjustment valve 53 arranged in parallel with the water supply pump 19.

Next, in the system a which is in the filtration state, the crude separator 9a
The coarse waste E separated by falls and settles at the bottom of the device 9a, and the filtrate B filtered by the filter 1a is sent from the filtrate outlet 32 to the fresh water tank 46 through the filtrate discharge line 6a. It will be done. At this time, the cleaning liquid switching device 8
b is opened and the pressure is released from the filter 1b side, so a part of the filtrate B passes through the cleaning liquid supply line 7 and enters the filtrate outlet 32 of the filter 1b in the other system as the cleaning liquid C. Supplied under pressure. At this time, the inflow of the cleaning liquid C is assisted by utilizing the differential pressure between the check valves 47a and 47b provided in the filtrate discharge systems 6a and 6b, respectively. In this example, the cracking pressure of the check valves 47a and 47b was fully opened to 0.3 kg/crd. Of course, the filtrate discharge system 6 is closed by the check mechanism of the check valve 47b on the opposite side.
The filtrate B does not flow into the other filter 1b through the filter 1b.

In the filter tb of the system to which the cleaning MC is supplied from the filtrate discharge port 32, the dirt adhering to the lower surface of the filter material 2b is removed by the liquid of the cleaning fluid C that passes through the filter material 2b from above to below. The peeled dirt passes through the opening 28 of the coarse separator 9b and falls to the bottom of the coarse separator 9b. At this time, the backwashed liquid R that has passed through the filter medium 2b is returned to the inlet of the water supply pump 19 through the dirty liquid reduction system 12b from the cleaning liquid switching device 8b opened as described above.

Incidentally, the excess filtrate B that cannot pass through the washing liquid switching device 8b cracks the check valve 47b of the filtrate discharge system 6b and flows through the same system 6b without entering the filter 1b of the system. The water is then sent to the fresh water tank 46.

When a certain predetermined time period ends, contrary to the above case, the dirty liquid changer 5b of the system path A is opened, the dirty liquid changer 5a of the system path A is closed, and slightly before that, the cleaning liquid changer 8a is opened.
, 8b are switched in the opposite manner to the above, and the system path a is switched to the backwashing state and the system path A is switched to the filtration state. As a result, the dirty liquid A pumped up by the water supply pump 19 is supplied only to the filter 1b in the system channel, and the rough separator 9 in the same system channel
The coarse garbage E separated by the filter 1b falls and settles at the bottom of the device 9b, and the dirty liquid A is filtered by the filter 1b.

The filtrate B filtered by the filter 1b of the system is sent from the filtrate outlet 32 to the fresh water tank 46 through the filtrate discharge line 6b, and a part of it is sent as the cleaning liquid C to the cleaning liquid supply system. 7 and is supplied to the filtrate discharge port 32 of the filter 1a of the system a.

A system path a to which the cleaning liquid C is supplied from the filtrate discharge port 32
In the filter 1a, dirt from the filter medium 2a is peeled off in the same manner as described above and falls to the bottom of the coarse separation device 9a and settles. At this time, the backwashed liquid R that has passed through the filter medium 2a returns to the inlet side of the water supply pump 19 through the dirty liquid reduction system path 12a by the opened cleaning liquid switching device 8a. The excess cleaning liquid B that cannot pass through the cleaning liquid switching device 8a cracks the check valve 47a of the filtrate discharge system 6a and
a, and is sent to the fresh water tank 46.

In this embodiment, the dirty liquid changers 5a and 5b are used with long opening/closing time, and the cleaning liquid changers 8a and 8b are used with short opening/closing times. By doing this, when the switching devices 5a, 5b, 8a, and 8b are switched, for example, the dirty liquid switching device 5 on the filter 1a side of the system a
While a is still open and the dirty liquid switching device 5b on the filter 1b side of the system path is still closed, the cleaning liquid switching device 8b, which had been open until then, is closed, and the filter discharged from the filter 1a is closed. Liquid B enters the filter 1b and fills the inside of the filter 1b. Therefore, when the dirty liquid switch 5b is switched to open and the dirty liquid switch 5a is switched to close, the filter 1
The filtrate B is discharged from b, so that the discharge of the filtrate B is not interrupted.

Further, in the illustrated embodiment, when switching between the two systems a and b, the sediment discharge valves 52a and 52b of the sediment discharge devices 10a and 10b are opened for a short time (2 to 3 seconds),
The filth settled at the bottom of the rough separators 9a and 9b can be discharged to the sediment discharge system 51 by the hydraulic pressure of the cleaning liquid C supplied under pressure, and can be discharged to the sludge box 50 through the same system 51. It is.

As shown in FIG. 3, this sludge box 50 includes an outer container 55, a bag-type filter 56, and a bag-type filter 56.
It consists of a protective screen 57 that protects the. In the sludge box 50 of this embodiment, the liquid contained in the sediment F discharged into the bag-type filter 56 passes through the filter 56 and falls into the container 55. The water is discharged from the outlet 58 into the fresh water tank 46. Furthermore, in this embodiment, when the bag-type filter 56 becomes clogged and the dirty liquid A overflows onto the filter 56, the liquid level detection switch 59 attached to the upper part of the container 55 is turned on and a signal is sent. , alarms are issued using buzzers, patrol lights, etc. When this bag-type filter 56 becomes clogged, it may be discarded together with the bag, or it may be washed and reused.

Further, a pressure switch 60 and a pressure gauge 61 are provided between the dirty liquid supply port 22 of the rough separation device @9a, 9b and the dirty liquid switch 5a, 5b. This is because if the filter media 2a and 2b of the filters 1a and 1b become clogged, the supply pressure to the dirty liquid will increase, so when the pressure exceeds a certain set pressure with the pressure switch 60, a signal will be generated and a buzzer or a patrol light will be generated. etc., and the filters 1a, 1
This is to stop b. At this time, the pressure is indicated on the pressure gauge 61.

FIGS. 2 and 4 show other embodiments of the liquid filtration device of the present invention. In this embodiment, only one phase separation device 9a is provided as shown in FIG. 2, and the dirt i4! iA is pumped up from the waste liquid tank 18 by the water supply pump 19 and sent to this coarse separator 9a, and the dirty liquid A from which the coarse waste E has been removed by the separator 9a is passed through eight filters 1a, 1b (second figure)
This is a large-capacity liquid filtration device that distributes and filters liquids. The liquid filtration device of this embodiment achieves a processing capacity of 1002 cells per minute.

As shown in FIG. 7, the rough separator 9a has a baffle plate 23 on the inside of its peripheral wall 21. A shielding plate 25 and an inclined plate 27 are provided. In this coarse fraction 1 device 9a, the dirty liquid A from which the coarse waste E has been removed is transferred to the gap 2 between the baffle plate 23 and the inclined plate 27.
6, and is discharged from two dirt liquid discharge lowers 1a and 71b provided on the upper lid 70 of the spacer M9a. In addition, a sediment discharge port 20 is provided at the bottom of the device 9a.
is provided.

The eight filters 1a and 1b shown in FIG. 2 are of the same closed pressurized type, and as shown in FIG. A
is supplied under pressure, the filter media 2 in the filters 1a and 1b
a, 2b from the bottom to the top to be filtered, and the same filter medium 2
The filtrate B filtered by filters 1a and 2b is filtered by filters 1a and 1b.
The filtrate is discharged from a filtrate discharge port 32 provided at the top of the canopy 31. At this time, the dirt is removed from the filter material 2.
It is attached to the lower surfaces of a and 2b.

In addition, in the filters 1a and 1b, when the cleaning liquid C is supplied under pressure in the opposite direction from the filtrate outlet 32 as shown in FIG. 8, the pressure of the cleaning liquid C passing through the filter media 2a and 2b from top to bottom will The dirt adhering to the lower surfaces of the filter media 2a, 2b is peeled off and falls downward to settle.

At this time, the backwashed liquid R that has backwashed the filter media 2a, 2b is transferred from the pressure release port 33 shown in FIG. 8b, the dirty liquid is returned to the inlet side of the water supply pump 19 through the dirt liquid reduction circuits 12a and 12b.

Further, as shown in Fig. 4, a sediment discharge port 39 is provided at the lower end of the filters 1a and 1b to discharge the sediment F that has fallen and settled, and is discharged by the sediment discharge devices 11a and 11b. It is. The sediment discharge devices 11a and 11b of the filters 1a and Ib are composed of sediment discharge valves 91a and 91b attached to the outlet of the discharge port 39, and a sediment discharge system 92, and the system passage 92 is a sludge discharge system. It is connected to box 50.

Note that the screen basket 4 of the filter media 2a, 2b
The structure of the installation of No. 4 is the same as that shown in FIG. 5C.

The eight filters 1a and 1b in FIG. 2 are divided into two groups of four, and each group has a rough separation device 9a or 9b in FIG.
are connected to the dirt liquid discharge lowers 1a and 71b.

The filtrate discharge ports 32 of each filter 1a, Ib are integrated for each set, and check valves 47a, 47 as shown in FIG.
It is connected to the filtrate discharge lines 6a and 6b via 7b. In addition, the cleaning liquid supply line 7 has two dirty liquid discharge lowers 1a.
, 71b.

Further, dirt liquid switching devices 5a, 5b are installed in the middle of the dirt liquid supply lines 3a, 3b.

The plurality of filters 1a and 1b are installed above the coarse separation device 9a, for example, as shown in FIG. 11. In the system shown in FIG. 11, four pillars 101 are set up on the outside of the rough separator 9a, a receiving plate 100 is mounted on the pillars 101, and three filters 1a and 1b are mounted on the receiving plate 100. By installing the filters in two rows, the installation area of the entire filtration device can be reduced.

The filtration apparatus of the present invention shown in FIGS. 2, 4, 7, and 8 is used in the following manner.

First, when the dirty liquid A is pumped up by the water supply pump 19, the same dirty liquid A is supplied to the dirty liquid supply port 22 of the coarse separation device 9a, and the coarse waste E is separated by the same device 9a and then
It settles to the bottom of the The dirty liquid A from which the bulky waste E has been removed in this way is delivered to the two dirty liquid discharge lowers 1a of the device 9a,
It is discharged from 71b.

When one of the dirty liquid changeover devices 5a and 5b connected to the dirty liquid discharge lowers 1a and 71b of this rough separation device 9a is opened and the other dirty liquid changeover device 5b is closed, the system Dirty liquid A is present only in the four filters 1a of route a.
are supplied and filtered by these filters 1a. At this time, of the cleaning liquid switching devices 8a and 8b, the cleaning liquid switching device 8a of the same system path a is closed, and the cleaning liquid switching device 8b of the other system path is opened.

As a result, the other four filters 1b among the primary filters 1a and 1b are divided into systems for backwashing.

The filtrate B filtered by the four filters 1a of the system a is discharged from the filtrate discharge ports 32 and integrated, and is discharged to the fresh water tank 46 through the filtrate discharge system 6a, and the cleaning fluid The cleaning liquid C is supplied under pressure through the supply line 7 to the filtrate discharge ports 32 of the four filters 1b in the other line.

In the filter 1b of the same system, which is supplied with the cleaning liquid B from the filtrate discharge port 32, dirt adhering to the lower surface of the filter medium 2b is peeled off and falls to the bottom of the filter 1b. At this time, the dirty liquid A that has passed through the filter medium 2b is transferred from the pressure release port 33 to the dirty liquid reduction system 1 by the opened cleaning liquid switching device 8b.
2b and returns to the inlet side of the water supply pump 19.

When a certain predetermined period of time has ended, the other dirty liquid switching device 5b is opened in the opposite manner as described above, and one of the dirty liquid switching devices 5a is closed to switch the two systems a and b, and at the same time, the two cleaning liquid switching devices Opening and closing of 8a and 8b are switched in the opposite manner to the above. As a result, the system enters the filtering state, and in the four filters 1a of the system a, which are supplied with the cleaning liquid C, the dirt on the filter media 2a is peeled off in the same manner as described above, and the filters are filtered. It falls and settles to the bottom of 1a.

In this embodiment, the filter 1a,
The sediment discharge device 11a, 1 attached to the bottom of 1b
1b sediment discharge valves 91a, 91b for a short time (2~
3 seconds), the precipitate F that has settled at the bottom of the filters 1a and 1b is discharged into the precipitate discharge system line 92 by the hydraulic pressure of the washing liquid C supplied under pressure, and is passed through the same line 92 to the sludge box 50. be discharged. The same operation as above is performed by automatic opening and closing of the valve 52a (FIG. 4) provided at the bottom of the rough separator 9a.

This sludge box 50 has the same structure as the one in FIG.

In the present invention, filter materials 2a and 2b that are difficult to adsorb dirt and are easy to peel off are used.

For example, polypropylene or polyester non-woven fabrics are layered on the front and back sides of a base fabric with excellent strength, and the surface (lower surface) of these non-woven fabrics on which dirt adheres is baked and then heat-treated to make it smooth. This makes it difficult for dirt to be adsorbed to its surface, and the adsorbed dirt is easily peeled off. filter material 2a,
2b is not limited to cloth, but resin sheets, metal sheets, etc. can also be used. Moreover, the shape of the filter media 2a, 2b may be flat or other shapes.

(Effects of the Invention) The liquid filtration method and device of the present invention have the following effects.

1. Filtration is performed in the filter 1a of one system a, and backwashing is performed in the filter 1b of the other system, and these systems a and b are alternately switched and the filtration device is completely stopped. Since the filter media 2a and 2b are always backwashed without any problems, and the filtrate B is always discharged as shown by the solid line in FIG. 9, the filtration and cleaning efficiency is very high.

2. If the filtration of the dirty liquid A and the backwashing of the filter media 2a, 2b are switched in a timely manner, the filter media 2a, 2b will be backwashed while the amount of dirt attached to the filter media 2a, 2b is small. Same filter material 2
a and 2b are less likely to be clogged, and there is little variation in the amount of filtrate B discharged due to the adhesion of dirt to the filter medium 2a, and the amount of discharged fluid B is stabilized.

3 As shown by the solid line in Fig. 10, the filter media 2a, 2
Since the regeneration rate (summer rate) of b is dramatically improved compared to the conventional method, and the regeneration recovery rate hardly decreases, the filter media 2a and 2b can be used interchangeably for a long period of time, which reduces costs accordingly. is reduced.

4. Since a part of the filtrate B filtered by one of the filters 1a or 1b is used as the cleaning liquid C, there is no need to separately prepare air or liquid for cleaning, which is convenient.

5. Since the dirt liquid A flows upward from below the filter media 2a, 2b, dirt adheres to the lower surfaces of the filter media 2a, 2b. Therefore, by backwashing by flowing the cleaning liquid C from above to below the filter media 2a, 2b, dirt adhering to the lower surfaces of the filter media 2a, 2b can be easily peeled off.

6 The peeled filth settles and accumulates below the filters 1a and 1b, and the accumulated sediment Fii filter 1
Since the sediment F is discharged to the outside from the sediment discharge port 20 (Fig. 5a) at a timely manner by the sediment discharge devices 11a and 11b provided at points a and 1b, the treatment of the sediment F becomes easy.

7 The coarse waste D separated by backwashing is sent to the coarse separator 9a,
Because of the structure that makes it easy to settle to the bottom of 9b, the backwashed dirt liquid A does not contain coarse dirt D. Therefore, even if the dirty liquid A that has been backwashed through the filter 1b is returned to the inlet side of the liquid suction pump 19 and circulated, the liquid suction pump 19 will not be clogged with coarse dirt or break down. Therefore, conventional filtration - backwashing, backwashing →
It has become possible to perform continuous filtration and backwashing by eliminating the discharge of backwashing liquid from the system, which was the biggest drawback of alternating filtration.

8. Sediment F deposited in crude separator i19 a, 9b
is discharged to the outside by the precipitate discharging device 10a and Job provided in the rough separation devices 9a and 9b, so that the precipitate F can be easily processed.

9 The backwashed liquid R that has backwashed the filter 1a or 1b is returned to the inlet side of the liquid suction pump 19, so the backwashed liquid R is not released to the outside of the filtration system but is circulated and used effectively. . Moreover, since the backwashed liquid R is not discharged to the outside of the filtration system, there is no need to separately process the backwashed liquid R outside.

10 Dirty liquid changer 5a, 5b and cleaning liquid changer 8a
, 8b, the filtration and backwashing of both the filters 1a and 1b are automatically switched at appropriate times for automatic operation.

11 The filter material 2 is placed between the receiving edge 21a protruding from the outer periphery of the container 21 of the filters 1a and 1b and the holding part 31a of the canopy 31.
Since the peripheral edges of a and 2b are clamped and fixed, the filtration area of the filter media 2a and 2b can be increased accordingly, and if the filters 1a and 1b are of the same size, the filtration efficiency will be improved.

12.i! Since the coarse waste E is removed by the coarse separators 9a and 9b provided before the single passers 1a and 1b,
The amount of dirt C adhering to the filter media 2a and 2b of the filters 1a and 1b is small (as a result, the filtrate B can be discharged more stably).

13. The rough separators 9a and 9b utilize the flow force of the dirty liquid A to generate a downward spiral flow, thereby causing the coarse waste E to settle, so unlike the conventional devices, the structure is simple and inexpensive. Easy to put into practical use.

14. The backwashed liquid R that has been used to backwash the filters 1a and 1b is returned to the inlet side of the liquid suction pump 19 that pumps up the γq liquid in the dirty liquid tank 18, so that the backwashed MR is filtered. Since the backwashed liquid R is not discharged to the outside of the system and is circulated and effectively used, and the backwashed liquid R is not discharged to the outside of the filtration system, there is no need to separately process the backwashed liquid R outside.

15. One or more filters 1 in each crude separator 9a, 9b
Since a and 1b are attached, the rough separators 9a and 9b and the filters 1a and 1b can be used as a set, which simplifies the configuration of piping and the like.

16. Housing 10 for one or both of the rough separation devices 9a and 9b
Since a plurality of filters 1a and 1b are mounted on the liquid filter 0, even if the number of filters 1a and 1b increases, the installation area of the liquid filtration device can be small.

17. The switching of the dirty liquid changers 5a and 5b is performed later than the switching of the cleaning liquid changers 8a and 8b, so when switching between them, one side must be turned off until the dirty liquid changers 5a and 5b are switched to open and close. The filtrate B continues to be discharged from the filter 1a, and the filter 1b is filled with the filtrate B.

Therefore, even if the dirty liquid switch 5a is subsequently switched to close and the dirty liquid switch 5b is switched to open, the filtrate B can be continuously discharged from the filter 1b and the filter 1a can be immediately backwashed. can.

18. Since the check valves 47a and 47b are provided, more dirty liquid A passes through the cleaning liquid switch 8a or 8b and returns to the water supply pump 19.
Even if it cannot pass through b, the dirty liquid A and filter material 2
Cleaning liquid B that backwashes a does not overflow.

[Brief explanation of drawings]

1 and 2 are overall circuit diagrams showing different embodiments of the liquid filtration method of the present invention, FIG. 3 is an overall configuration diagram of the liquid filtration apparatus shown in FIG. 1, and FIG. 4 is a liquid filtration device shown in FIG. A structural diagram showing the installed state of the rough separator and filter of the apparatus, FIG. An explanatory diagram showing the flow of liquid in the device, FIG. ,
FIG. 7 is a vertical cross-sectional view of the coarse separation device of the liquid filtration device shown in FIG. 4, FIG. 8 is a vertical cross-sectional view of the filter shown in FIG. 4, and FIG. FIG. 10 is a comparison diagram showing the filtration time and the variation width of the filtration discharge amount; FIG. 10 is a comparison diagram showing the number of backwashing times and regeneration recovery rate of the present invention and the conventional filtration method and device
Fig. 11a is a plan view showing the state in which the filter is installed in the rough separator according to the present invention, Fig. 11 is a front view showing the state in which the filter is installed, and Fig. 12 is a plan view showing the state in which the filter is installed in the coarse separation device according to the present invention. An explanatory diagram of filtration and backwashing. FIG. 13 is an explanatory diagram of filtration and backwashing of a conventional cartridge type filter medium. a and b are system paths 1a, 1b is a filter 2a, 2b is a filter medium 3a, 3b is a supply system path 5a, 5b is a dirty liquid switch 6a, 6b is a filtrate discharge system 7 is a cleaning liquid supply system 8a, 8b is a cleaning liquid switching device 9a, 9b is a coarse separation device 10a, 10b is a sediment discharge device 11a, 11b is a sediment discharge device R is backwashed liquid

Claims (14)

[Claims] (1) Two systems a and b incorporating filters 1a and 1b
Among them, the dirty liquid A is supplied to the filter 1a or 1b of one system a or a, and the same dirty liquid A is filtered, and the other system is supplied to the filter 1b or 1a of the system a. A part of the filtrate B filtered by the filter 1a or 1b is supplied as a washing liquid C, and the washing liquid C is used to filter the filter 1b or 1a.
A liquid filtration method characterized in that the filth D adhering to the filter medium 2b or 2a is backwashed and allowed to fall and settle, and the filtration and backwashing of both the systems a and b are switched at an appropriate time. (2) The dirty liquid A is filtered by flowing upward from below the filter media 2a, 2b in the filters 1a, 1b, and the cleaning liquid C is poured from above the filter media 2a, 2b in the filters 1a, 1b. A liquid filtration method according to claim 1, characterized in that backwashing is carried out by flowing downward so that the dirt D adhering to the filter media 2a, 2b falls and settles. (3) A claim characterized in that the dirty liquid (backwashed liquid) R obtained by backwashing the filter 1b or 1a is returned to the inlet side of the water suction pump 19 that pumps up the dirty liquid in the dirty water tank 18. Item 1 or 2 liquid filtration method. (4) two systems a and b incorporating filters 1a and 1b that filter the dirty liquid A supplied from the water supply pump 19;
Supply lines 3a and 3b that supply dirty liquid A to both lines a and b
, dirty liquid switching devices 5a and 5b that switch the supply of dirty liquid A to the supply lines 3a and 3b, and filtrate B filtered by both filters 1a and 1b to the outside of both filters 1a and 1b. The filtrate discharge systems 6a and 6b are used to discharge a part of the filtrate B filtered by the filter 1a or 1b of one system a or the other system or the filter 1b or 1a of the system a. , a cleaning liquid supply line 7 that supplies a cleaning liquid that backwashes the dirt D adhering to the filter media 2b or 2a and causes it to fall and settle;
A liquid filtration device comprising cleaning liquid switching devices 8a and 8b for switching the supply of cleaning liquid C to the supply line 7. (5) The periphery of the filter media 2a, 2b is clamped and fixed between the receiving edge 21a protruding from the outer periphery of the container 21 of the filter 1a, 1b and the holding part 31a of the canopy 31. A liquid filtration device according to claim 4. (6) The cleaning liquid switching devices 8a, 8b and the water supply pump 19
A reduction line 12a that returns the backwashed liquid R that has backwashed the filter 1b or 1a to the inlet side of the water suction pump 19,
12. The liquid filtration device according to claim 4, further comprising: 12b. (7) The system is characterized in that coarse separators 9a and 9b are provided in front of the filters 1a and 1b of both the systems a and b, respectively, for separating coarse waste E with a large specific gravity from the dirty liquid A. Claim 4
liquid filtration equipment. (8) The liquid filtration device according to claim 4 or 7, characterized in that one or more of the filters 1a, 1b are connected after each of the rough separation devices 9a, 9b. (9) The two rough separators 9a and 9b are used in common, and the filters 1a and 1b of the two routes a and b are connected after the one rough separator 9a or 9b. A liquid filtration device according to claim 8. (10) The liquid filtration device according to claim 8 or 9, characterized in that a plurality of filters 1a and 1b are mounted above one or both of the rough separation devices 9a and 9b. (11) Claim 7, 8, 9, or 10, characterized in that the coarse separation devices 9a, 9b are provided with sediment discharge devices 10a, 10b for discharging the sediment F deposited on the bottom thereof. liquid filtration equipment. (12) Sediment discharge devices 11a and 1 for discharging the sediment F deposited on the bottoms of the filters 1a and 1b to the outside.
1b. 1b. The liquid filtration device according to claim 4, or 6, or 7, or 8, or 9, or 10 or 11. (13) The cleaning liquid switching device 8a which switches the supply of the cleaning liquid C to the cleaning liquid supply system 7 by switching the dirty liquid switching devices 5a and 5b that switches the supply of the dirty liquid A to the supply system paths 3a and 3b. , 8b. 4. The liquid filtration device according to claim 4, wherein the switching is performed later than the switching of the switches. (14) Filtrate discharge systems 6a and 6 that discharge the filtrate B filtered by the filters 1a and 1b to the fresh water tank 46
Check valves 47a and 47 that normally prevent the discharged filtrate B from flowing into each of the valves 47a and 47b crack and allow the filtrate B to flow in when the filtrate B exceeds a certain pressure.
4. The liquid filtration device according to claim 4, further comprising: b.