WO2005102495A1

WO2005102495A1 - Rotary compression filter with slit blow scraper

Info

Publication number: WO2005102495A1
Application number: PCT/JP2004/005801
Authority: WO
Inventors: Kouji Fujimoto; Jun Ohashi
Original assignee: Tomoe Engineering Co. Ltd.
Priority date: 2004-04-22
Filing date: 2004-04-22
Publication date: 2005-11-03
Also published as: CN1933886A; JPWO2005102495A1

Abstract

A rotary compression filter (3) capable of not only peeling off and removing a solid matter layer adhesively formed on the inner surface of a screen but also eliminating particulate lumps accumulated in the small holes of the screen to properly eliminate the clogged state of the screen, wherein pressure is gradually applied to original liquid to be treated as the original liquid is moved forward in an annular filtration chamber (41) formed around a rotating shaft (32) to change the liquid-like original liquid in a cake shape for dehydration treatment. The filter (3) is characterized in that scrapers (40) so formed as to be able to inject gas or liquid toward the inner surface of the screen (35) are mounted on the inner surface of the screen (35) so that the edges thereof are brought into contact with that surface at acute angles.

Description

Description Rotary compression filter having a slit blow type scraper

The present invention is an apparatus for performing dehydration by filtering and pressing a mixture of a solid substance and a liquid substance (processed undiluted solution) such as a raw material of a processed food, a semi-processed product thereof, or sludge. The present invention relates to a rotary compression filter that performs a dehydration treatment by gradually applying pressure to a stock solution to be processed as it progresses in a formed annular filtration chamber. Background art

A rotary compression filter (rotary press filter) is, for example, as disclosed in Japanese Patent Application Laid-Open No. 2001-113109, in which an annular filtration chamber formed around a rotation axis is processed. This is a device that introduces the stock solution and rotates the hollow disk-shaped screen to advance the stock solution to the front, and gradually applies pressure to perform the dehydration process.

More specifically, the processing stock solution is introduced into the filtration chamber from the stock solution supply port, and sequentially proceeds in the filtration chamber in a predetermined direction due to the frictional force generated between the stock solution and the rotating screen. At this time, since the screen has a large number of small holes, as the undiluted solution passes through the filtration chamber, the moisture in the undiluted solution passes through the small holes of the screen and goes out of the filtration chamber. It will be discharged first. The treated stock solution, which was in a liquid state at the time of introduction into the machine, becomes semi-solid before passing through a position (initial filtration zone) about half a lap from the stock solution supply port. It is discharged (extracted cake) from the cake outlet to the outside of the machine. Since the screen rotates continuously, it returns to the initial filtration zone after passing through the initial filtration zone, the subsequent filtration, squeezing zone, and final squeezing zone. It will be transported continuously. In a conventional rotary compression filter, a scraper whose edge contacts the inner surface of the rotating screen at an acute angle is attached, and the surface of the screen is covered by the lump of fine particles contained in the processing stock solution. Some are designed to avoid this situation. '

However, such a scraper has a problem that, although it is possible to remove the solid material layer attached to the inner surface of the screen, it is difficult to remove the fine particle mass that has entered the small holes of the screen. is there. Disclosure of the invention

The “rotary compression filtration machine” of the present invention has been made to solve the above-mentioned problems of the prior art, and as the solution proceeds in an annular filtration chamber formed around the rotation axis, In a rotary compression filter that dewaters the liquid by changing the undiluted solution into a cake, the edge is sharply in contact with the inner surface of the rotating screen. The scraper is characterized in that the scraper is configured to be able to jet a gas or a liquid toward the inner surface of the staline.

It is preferable that the scraper is disposed in a range (initial filtration zone) from the undiluted solution supply port to about a half turn. The solids layer can be mechanically peeled off during the initial filtration stage, and Fine particles agglomerating into the small holes can be directly eliminated, and clogging at the initial filtration stage can be suitably prevented.

In addition, when the cleaning liquid or gas is configured to be ejected from the scraper at a pressure higher than the liquid pressure on the inlet side of the untreated solution, it is more preferable to remove the fine particle clumps remaining in the stirrup holes. Can be.

The “scraper for a rotary compression filter” according to the present invention is characterized in that a large number of openings facing the inner surface of the screen are formed along the longitudinal direction, and a flow path communicating with the opening. Is formed. Brief Description of Drawings

FIG. 1 is a sectional view of a rotary compression filter 3 according to the present invention.

FIG. 2 is a cross-sectional view taken along line AA of the rotary compression filter 3 shown in FIG.

FIG. 3 is an enlarged view of the scraper 40 shown in FIG.

FIG. 4 is a sectional view taken along line CC of the scraper 40 shown in FIG.

FIG. 5 is an explanatory diagram of a cleaning process of the fine particle mass by the scraper 40.

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. FIG. 1 is a sectional view of a “rotary compression filter” according to the present invention. As shown, the rotary compression filter 3 includes a rotating shaft 32, an inner ring spacer 33, an outer ring spacer 34, two donut-shaped water-permeable screens 35, 35, It is composed of a partition plate 36, an outer casing 37, and a drive device (not shown). The rotating shaft 32 is held almost horizontally, and is rotated at a low speed (about 0.2 to 3 rotations Z) in the direction of arrow B shown in FIG. 1 by the driving force supplied by the driving device. It is supposed to. The inner ring spacer 33 is fixed around the rotation axis 32, and rotates according to the rotation axis 32.

The outer race spacer 34 is arranged outside the inner race spacer 33 and fixed and held by an outer casing 37 (see FIG. 2). Further, the outer ring spacer 34 is arranged so as to always face the inner peripheral surface 34 c force S and the outer peripheral surface 33 a of the inner ring spacer 33 at a constant interval.

The two screens 35, 35 have a diameter of 0.3 to ensure water permeability.

It has a large number of small holes of about 8 mm, and functions as a filter for removing water from the processing stock solution as described later.

These screens 35, 35 are fixed on both side surfaces of the inner ring spacer 33, respectively, and rotate together with the rotating shaft 32 and the inner ring spacer 33 when they rotate. It has become. Further, the screens 35 and 35 are arranged at positions and dimensions such that the outer peripheral edge portions are close to both side surfaces of the outer ring spacer 34.

The partition plate 36 is held substantially horizontally and in a direction orthogonal to the axial direction of the rotating shaft 32. The inner end 36a of the partition plate 36 matches the curvature of the outer peripheral surface 33a of the inner ring spacer 33, and is formed so as to be in surface contact with the curvature and slide.

The outer end 36b (the end opposite to the inner end 36a) of the partition plate 36 is between the base end 34a and the end 34b of the outer ring spacer 34. , And are held at predetermined intervals. The space secured between the outer end 36 b and the base end 34 a of the outer ring spacer 34 serves as a stock solution supply port 38 for supplying a stock solution to be introduced into the apparatus. Used for The space secured between the outer end 36 b and the end 34 b of the outer race spacer 34 functions as a cake outlet 39. The rotary compression filter 3 is sealed by an outer casing 37 except for a stock solution supply port 38, a cake outlet 39, and a liquid discharge port 42. The rotary compression filter 3 is a space formed between the filtration chamber 41 (the inner ring spacer 33 and the partition plate 36 and the outer ring spacer 34). A space from the stock solution supply port 38 to the cake outlet 39 is formed. As shown in FIG. 2, the cross section of the filtration chamber 41 has a rectangular shape, and, as shown in FIG. 1, a portion extending in an annular (C-shaped) shape. (Annular part) and a part (straight part) extending linearly.

Further, a large number of scrapers 40 are attached to the outer ring spacer 34 of the rotary compression filter 3. These scrapers 40 are slit blow type scrapers, and are a lump of fine particles in the processing solution adhering to the inner surface of the screen 35 rotating in a predetermined direction and stay in the small holes of the screen 35. The fine particle clumps and the like can be suitably removed in the initial filtration stage, so that it is possible to suitably avoid a decrease in the amount of liquid removed due to clogging of the screen 35 (a decrease in processing capacity). .

More specifically, these scrapers 40 have a base end fixed to the side surface of the outer ring spacer 34 in a direction such that the tip thereof is directed toward the inner ring spacer 33. The edge is brought into sharp contact with the inner surface of the screen 35. In addition, four scrapers 40 are attached to each of the two sides of the outer ring spacer 34 (a total of eight scrapers on both sides). In the range (initial filtration zone), they are almost evenly distributed (at 45 ° intervals). FIG. 3 is an enlarged view of the scraper 40, and FIG. 4 is a sectional view of the scraper 40 of FIG. 3 taken along the line CC. As is clear from these figures, the scraper 40 has a narrower width at the tip portion 40a than at the base portion 40b side, that is, a “tapered shape”. The hollow channel 2 extending in the longitudinal direction is formed.

Also, on one surface of the scraper 40, a number of slits 4 are formed along the longitudinal direction. Each of these slits 4 is arranged inside (at a position close to the center) of the front end 40 c of the edge, and communicates with the hollow flow path 2. Then, the cleaning liquid is supplied into the inside of the scraper 40 (hollow flow path 2) from the opening 5 on the base end side side, and as shown in FIG. The cleaning liquid can be sprayed toward the side surface at a high pressure (higher than the liquid pressure on the inlet side of the processing stock solution). More specifically, the inlet side liquid pressure of the processing stock solution is usually 10 to 5 OKPa, but here, the cleaning solution is sprayed at a higher pressure of 0.4 to 1 MPa. be able to. That is, the slit 4 of the scraper 40 functions as an injection port for the cleaning liquid.

As described above, when the cleaning liquid is jetted from the slit 4 toward the inner surface of the screen 35 at a high pressure, the fine particles remaining in the small holes of the screen 35 are removed from the opposite side (the outer surface of the screen 35). ), The inside of the small hole can be washed, and the clogged state of the screen 35 can be eliminated. As described above, since the slits 4 are all located inside the edge tip 40c as described above, as shown in FIG.

As 3 5 rotates in the direction of arrow E, the tip of the edge of the scraper 40

At a stage after the solid material layer D attached to the inner surface of the screen 35 is removed by 40 c, the cleaning liquid can be directly sprayed into the small holes of the screen 35. Effectively eliminate clogging of screen 35 You can.

The cleaning liquid used here is not particularly limited, and may be, for example, water or warm water, or a surfactant or the like. When warm water, a surfactant, or the like is used, even if fats and oils or the like adhere or remain in the small holes of the screen 35, they can be suitably removed.

It should be noted that, instead of the high-pressure cleaning liquid, high-pressure air (or other gas) or high-temperature steam can be injected. In this case, it is possible to avoid a situation in which the washing liquid is mixed into the filtrate separated from the stock solution to be processed or a situation in which the washing liquid is diluted with the washing liquid. It is also possible to configure so that hot water and high-temperature steam can be injected at the same time.

Further, as shown in FIG. 4, the scraper 40 is formed by integrally molding the entire plate, or by using two plate members having grooves formed on the surface so that the grooves are on the inside. It is also possible to use a member in which a hollow flow path and a slit are formed inside by laminating.

Further, the shape of the injection port is not necessarily limited to the slit, and a large number of circular, elliptical, or rectangular injection ports may be arranged in parallel instead of the slit.

Further, it is desirable that the injection port is arranged so that the cleaning liquid or the like can be injected substantially over the entire area of the screen 35 in the radial direction. It is not necessary for the injection ports to be arranged over the entire range up to the part 40b. For example, among the plurality of scrapers 40 arranged, the first scraper 40 closest to the stock solution supply port 38 In, the injection port is formed only on the base end portion 40b side, and in the second scraper 40 adjacent to this, the injection port is formed only on the intermediate portion. In the third scraper 40, an injection port is formed only on the tip portion 40 a side, and the plurality of scrapers 40 are configured so that the entire area of the screen 35 is reinforced. You can also. With such a configuration, the opening area of the injection port in one scraper 40 can be reduced, and as shown in FIG. 3, the injection port is formed over almost the entire length in the longitudinal direction. Compared to the scraper 40, a larger injection pressure can be realized with a smaller supply pressure. Industrial applicability

Since the rotary compression filter of the present invention is configured so that gas or liquid can be ejected from the scraper toward the inner surface of the screen, the solid material layer adhered to the inner surface of the screen is formed. In addition to stripping off the particles, it is possible to remove the fine particle clumps remaining in the small holes of the screen, and it is possible to preferably eliminate the clogged state of the screen.

In addition, when a scraper capable of injecting gas or the like is disposed over the entire initial filtration zone or in a part of the initial filtration zone, clogging of the screen can be prevented in the initial filtration step. Therefore, the filtration efficiency can be improved, and a stable liquid removal level can be maintained even when a long-term operation is performed.

Claims

The scope of the claims

1. In a rotary compression filter that performs a dehydration process by gradually applying pressure to the processed stock solution as it progresses through an annular filtration chamber formed around the rotation axis and changing the liquid stock solution into a cake. ,

A scraper attached such that the edge contacts the inner surface of the rotating screen at an acute angle,

A rotary compression filter configured to be capable of injecting gas or liquid from the scraper toward the inner surface of the screen.

2. The rotary compression filter according to claim 1, wherein the scraper is disposed in a range from the undiluted solution supply port to about half a circumference.

3. The rotary compression according to claim 1, wherein the scraper is configured to be capable of injecting a cleaning liquid or a gas at a pressure higher than a liquid pressure on an inlet side of the processing stock solution. Filtration machine.

4. A rotary compression filter, characterized in that a number of injection ports opening toward the inner surface of the screen are formed along the longitudinal direction, and a flow path communicating with the injection port is formed. Scraper.