JPS638803B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a liquid filtration device suitable for removing pulp-like substances from pulp-containing sludge in sewage, food processing, and paper manufacturing processes.

That is, the present invention relates to a liquid filtration device incorporating a specially shaped filter element, and more specifically, the structure is simple and can be mass-produced, and even if the filter element becomes clogged, the filtration work will not be interrupted. The object of the present invention is to provide a liquid filtration device capable of performing filtration work on the one hand and backwashing work on the other hand.

Another object of the present invention is to provide a liquid filtration device that is small in proportion to its capacity, has few failures, and can particularly effectively filter sludge containing pulp-like substances.

In conventional liquid filtration devices, the filter surface of the filter element is regenerated by scraping off foreign matter clogged on the filter surface with a knife-shaped scraper.

Conventionally, this type of liquid filtration device has a structure in which a scraper provided in the direction of rotation of the filter element passes through a portion to which contaminants are attached to scrape off the contaminants. However, if this contaminant is a pulp-like substance, as shown in FIGS. 13 and 14, the filter element 1
Contaminants 4 that have accumulated across the plurality of openings 3 between the bars 2 that make up the filter element 1 are not scraped off by the scraper 6 and sneak into the back side of the scraper 6.
By simply moving on the surface of the filter element 1, especially when the filter element 1 is formed of a spirally wound wire, the contaminants 4 are likely to be collected in the direction of the arrow 7 and cause clogging.

Therefore, in order to eliminate the above-mentioned drawbacks, the present invention uses a filter element in which a plurality of concave grooves are formed across the limited openings between the bars, and the filter element is circumscribed to the filter element and the head box is formed in the direction of rotation of the filter element. A liquid filtration device having a first scraper provided at a distance from the filter element and a second scraper provided behind the scraper, and having a means for forcibly discharging contaminants on the outer periphery of the filter element. It is to provide.

Another object of the present invention is to provide a liquid filtering device in which the filter element has a backwashing function to effectively backwash the filter element, prevent clogging, and enable continuous operation for a long period of time. It is an object.

In conventional liquid filtration devices, a scraper installed close to the outer circumferential surface of the filter element scrapes off foreign matter clogging the liquid inlet side to prevent accumulation. ,
When the impurities are pulp-like substances, there is a drawback that the scraping means using a scraper and the backwashing means using filtered raw water do not effectively act on the filter element. The present invention has focused on this point and, as a result of intensive research, has made it possible to effectively scrape off and backwash the impurities from the filter element by making the filter element a special shape.

Embodiments of the present invention will be described below with reference to the drawings. In FIGS. 1 to 12, reference numeral 1 denotes a cylindrical filter element, which is composed of a large number of bars 2 arranged substantially parallel to each other at regular intervals. The bars 2 constituting this filter element 1 have openings (slits) 3 defined by adjacent bars, have a smooth outer peripheral surface, and have a tapered surface that spreads inward between adjacent opposing sides. ing. This filter element 1 is manufactured by a method in which a wire is wound spirally around the outer periphery of a drum having openings at a predetermined pitch, and the surface of the wire is cut and polished to form an inward expansion. A self-retaining slit plate with holes formed at predetermined intervals and V-cut grooves formed discontinuously to form an integral frame part is formed into a cylindrical shape so that the grooves expand inward. method, etc.

The filter element 1 also has grooves 11 at predetermined intervals on its smooth outer peripheral surface, which cross the defined openings 3 between the bars 2, and the grooves 11 are formed in the discontinuous portions. This groove 11 can be easily produced by cutting the slit plate and forming the slit plate having the groove 11 into a cylindrical shape. Further, the groove 11 is approximately perpendicular to the tangent line at the front in the rotational direction of the filter element 1, and is gently inclined at the rear. In particular, a notch 12 communicating with the opening 3 is formed on the right angle surface, and the gently inclined surface is a continuous smooth surface.

The filtering surface (outer peripheral surface of the bar) of the filter element 1 described above is smooth and has a surface mesh. The filter element 1 is rotated relative to a first scraper 6 installed close to its surface, and the scraper 6 straddles between the openings 3 and removes the foreign matter 4 stuck in the mesh into the groove 1.
Push forward to 1. Next, the filter element 1 is once reversed and the foreign matter 4 adhering to the scraper 6 is brushed off into the groove 11, and then the foreign matter 4 within the groove 11 is removed by the second scraper 13 (9th (see Figures 1-2), the filtration surface can be regenerated.

The first scraper 6 is attached to a mounting frame 14 erected around the outer circumference of the filter element 1,
The filter element 1 is elastically supported in a direction away from the surface of the filter element 1, and is fixed in contact with the filter element 1 by the shutter 15. On the contrary, the second scraper 13 is elastically supported by the mounting frame 14 so as to be used when facing the filter element 1 side, and its knife-shaped tip slides along the right angle surface of the groove 11 and scrapes the dirt. Scoop up item 4.

16 is a shutter installed below the second scraper 13.

The main body 20, which houses the filter element 1 horizontally on a horizontal shaft 21, has a head box 22 on one side of the filter element 1.
A sludge of contaminants 4 flows into the head box 22 through a liquid inlet 23, passes over a table 24, is filtered by the filter element 1, and then the filtered liquid is sent into the filter element 1. During this time, the filter element 1 is being rotated at low speed by the prime mover M. The liquid that has flowed down to the bottom surface of the main body 20 is discharged from the liquid outlet 26.

Reference numeral 25 denotes a brush that is rotatably attached to a horizontal shaft 21 that supports the filter element 1, and is normally suspended so that its tip comes into contact with the lowermost surface of the inner surface of the filter element 1. The brush 25 swings in accordance with the rotation of the filter element 1, appropriately brushing the inner circumferential surface thereof, and prevents the generation of slime (water algae). Note that 27 is a shock absorbing plate that is vertically installed approximately in the middle of the head box 22 and has a water passage portion at its lower part.

Next, the operation of the present invention will be explained.

Four grooves 11 are provided on the outer circumference of the filter element 1 at 90° intervals in the axial direction thereof. Of course, the number etc. of filter element 1
may be increased or decreased as appropriate depending on the diameter of the filter element 1. In either case, the filter element 1 is reversed after the groove 11 passes the first scraper 6, returns the groove 11 to the first scraper 6, and then 1st and 2nd
It rotates through the scrapers 6, 13.

At this time, the sludge mixed with pulp-like contaminants 4 is sent to the head box 22 through the liquid inlet 23. Therefore, when the filter element 1 is rotated at a low speed, the sludge is fed onto the filter element 1 via the table 24. As the filter element 1 rotates, the contaminants 4 become
While being conveyed onto the scraper 6, the filtered liquid passes through the filter element 1 and falls to the bottom surface of the filter element 1 like a waterfall, as shown by the arrow in FIG. 3, backwashing the filter element 1. .

In the present invention having the above configuration, the regeneration mechanism of the filter element 1 will be explained. The foreign matter 4 sent to the first scraper 6 is scraped off here and falls to the shooter 15. At this time, the pulp-like contaminants 4 stuck in the mesh across each opening 3 of the filter element 1 are caught on the tip of the first scraper 6 and pushed out into the groove 11, and as the filter element 1 reverses, removed from Next, each scraper 6, 13
While passing the part, the second scraper 13 is slid along the right angle surface of the groove 11, and the foreign matter 4 staying in the groove 11 is thoroughly scraped off. The above operation is then repeated for each groove 11 portion.

Note that the filter element 1 used in the present invention may have a polygonal shape as well as a perfect circular shape, and can smoothly operate against the scraper 6 to remove foreign matter on the outer periphery of the filter element 1. The intensive liquid flow from the side effectively regenerates the filter surface. Of course, if each opening 3 is formed perpendicularly to the axial direction of the filter element 1 obtained by forming a V-cut groove, the lateral movement of the contaminants 4 as in the conventional case can be prevented.

As described above, the liquid filtration device according to the present invention has
Since the inner periphery of the filter element 1 is effectively backwashed, clogging of the slit can be prevented for a long period of time. Therefore, with a small filtration device, filtration work can be performed automatically and continuously for a long period of time.

Further, since it is very easy to process the filter element into a special shape and the filter surface has extremely high smoothness, the foreign matter 4 including pulp-like substances can be scraped off extremely effectively. In addition, by simply operating the first and second scrapers 6 and 13 over the specially shaped filter element 1, the efficiency of removing impurities by the scrapers could be dramatically improved.

[Brief explanation of the drawing]

1 to 3 are a front view, a side view, and a sectional view, respectively, showing a liquid filtration device of the present invention, and FIG. 4 is a perspective view showing an example of a filter element used in the liquid filtration device of the present invention, FIG. 5 to FIG. 7 are longitudinal sectional views showing the main parts of the filter element;
A perspective view and a cross-sectional view, FIG. 8 is a cross-sectional view of the main part showing the scraper part of the liquid filtration device of the present invention, FIGS. 9 to 12 are cross-sectional views showing the process of scraping off foreign matter 4, and FIG. Figures 1 to 14 are a perspective view and a sectional view of a filter element in a conventional example. 1...Filter element, 2...Bar, 3
...Opening, 4...Contaminants, 5...Arrow, 6...Scraper, 11...Concave groove, 12...Notch, 13
...Scraper, 22...Headbox, 23
...Liquid inlet, 24...Table, 25...Brush, 26...Liquid outlet, M...Drive device.

Claims (1)

[Scope of Claims] 1 Consisting of a large number of bars that are arranged substantially in parallel at regular intervals and that have tapered surfaces that spread inward between adjacent opposing sides, and that are arranged on a smooth outer circumferential surface. A filter element having a plurality of concave grooves formed at predetermined intervals across limited openings between each bar, a device for supporting and rotating the filter element, and a head box opening toward the filter element. A liquid filtering device comprising: a first scraper that circumscribes the filter element and is spaced apart from the head box in the direction of rotation thereof; and a second scraper that is located behind the first scraper. 2. The liquid filtration device according to claim 1, wherein the filter element is constituted by a number of bars that are perpendicular to the axial direction and have a self-shaping ability. 3 The groove formed on the filter element
3. The filtering device according to claim 1, wherein the filter element is tilted approximately perpendicularly to the tangent at the front in the rotational direction of the filter element and gently tilted at the rear. 4. The liquid filtering device according to claim 3, wherein the groove has an opening communicating with the opening between the bars on the right-angled surface side, and has a flat surface on the gently inclined surface side. 5. The first scraper is placed on the outer periphery of the filter element at an acute angle to the tangent thereof, and the second scraper is provided on the outer periphery of the filter element at a substantially right angle to the tangent,
A liquid filtering device according to any one of claims 1 to 4, which is in contact with a groove so as to be movable back and forth. 6 After the filter element passes the first scraper during forward rotation, the groove passes through the first scraper.
The liquid filtration device according to any one of claims 1 to 5, wherein the liquid filtration device has an operating trajectory that rotates in reverse until it returns to the front of the scraper. 7. The liquid filtration device according to any one of claims 1 to 6, wherein the filter element includes a brush coaxially and freely supported so as to come into contact with the inner peripheral surface.