JPH0871320A - Continuous solid-liquid separation device - Google Patents

Abstract

PURPOSE: To prevent effectively the clogging of a filter medium, peel off and remove cakes easily and improve the durability of the filter medium. CONSTITUTION: A revolving filter with a cylindrical medium 2 is fitted on a cylindrical fixed drum 1 and revolved slightly. A number of air ventilation and liquid permeation holes are bored on the outer peripheral face of the fixed drum 1. The inner side of the cylindrical filter medium is vacuumized to suck a liquid content of a solid-liquid mixed fluid 10 and the filter medium 2 is passed through and sucked to the inside of the fixed drum and then discharged out of a system. Cakes 20 accumulated on the filter medium surface of the revolving filter are removed by a scraping blade 8. A pressurized gas jet opening 5 for spraying pressurized gas to the rear face of the filter medium is formed on the outer peripheral face of the fixed drum. The pressurized gas jet opening is faced to the vicinity of the scraping blade 8.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a solid-liquid separation device,
More specifically, the present invention relates to a solid-liquid separation device which prevents clogging of the surface of a filter medium and can continuously perform solid-liquid separation in a clean state.

[0002]

2. Description of the Related Art An apparatus for continuously separating a solid content and a liquid content from a solid-liquid mixed fluid containing impurities such as fine powder dispersed therein is described in, for example, JP-A-61-249515. A solid-liquid separation device having a configuration as shown in FIGS. 3 to 5 is known. In this solid-liquid separation device, both ends of a cylindrical filter medium 21 are sealed by flanges 22a and 22b, the filter medium is rotated while the inside is kept in a reduced pressure state, and the solid-liquid mixed fluid stored in a storage tank 9 due to a pressure difference. The liquid content of 10 is sucked and removed so that the solid content is accumulated on the surface of the filter medium in a layered manner, and the accumulated cake 20 is scraped off by the scraping blade 8 provided along the side surface portion. It can be separated into minutes.

However, since this apparatus is a system for continuously forming a cake of solid content on the surface of the filter medium, some of the particles are not captured on the surface of the filter medium during continuous suction filtration. When it penetrates into the inside, it gets caught in the tissue of continuous pores and causes clogging, gradually increasing the pressure loss and lowering the ventilation liquid permeability, and the separation efficiency between the solid and liquid components deteriorates. In order to avoid such a phenomenon, when removing solids with a scraping blade, a part of the surface layer of the filter medium is scraped off very thin at the same time. The layer is not limited to a layer, and the filter medium is gradually thinned as it is scraped, and eventually becomes unusable and must be replaced, and the usable time of the filter medium itself is short and there is a problem in durability.

[0004]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned circumstances, and its object is to separate a solid content and a liquid content from a solid-liquid mixed fluid containing impurities. It is an object of the present invention to provide a solid-liquid separation device capable of effectively preventing clogging of a filter medium and performing solid-liquid separation with excellent durability in a device for continuously performing the above.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to provide a rotary drum 3 having a cylindrical filter medium 2 on a fixed drum 1 having a cylindrical outer peripheral surface provided with a large number of ventilation liquid passage holes 4. The inside of the fixed drum is kept in a depressurized state by a negative pressure device while being fitted and slidingly rotated, and the inside of the cylindrical filter medium is also in a depressurized state, so that the liquid component of the solid-liquid mixed fluid becomes more In a solid-liquid separation device that removes the solids accumulated on the surface of the filter medium of the rotary filter by a scraping blade 8 after suctioning and passing the filter medium through the fixed drum. And a continuous solid-liquid characterized in that a pressurized gas ejection port for blowing a pressurized gas to the back surface of the filter medium is arranged on the outer peripheral surface of the fixed drum so as to be directed near the tip of the scraping blade. Achieved by a separation device.

The filter medium used in the present invention has a cylindrical shape, and preferably has a relatively small pressure loss. The type of the filter material is not particularly limited, and examples thereof include a metal nonwoven fabric, a filter fabric, a synthetic resin porous body, and the like. Among them, the metal nonwoven fabric has excellent dimensional stability against liquid. It is suitable in that In the present invention, the filter medium may be in sliding contact with the fixed drum, but it is preferable that a slight gap be provided between the filter medium and the fixed drum because the filter surface of the filter medium can be effectively used.

The cylindrical outer peripheral portion of the fixed drum according to the present invention comprises a portion having a large number of ventilation liquid passage holes communicating with the inside of the fixed drum, and a portion provided with a pressurized gas jet port. Moreover, you may arrange | position the part which does not provide either of them as needed. That is, the rotating filter medium is composed of a portion where the inside is depressurized and sucks the liquid component, and conversely, a portion where the inside is pressurized and the gas is ejected to the outside.

In the present invention, the pressurized gas ejection port is opened toward the vicinity of the tip of the scraping blade, but is opened so that the pressurized gas is ejected at least above the scraping blade tip. It is a thing. The specific structure of the pressurized gas ejection port is not particularly limited as long as it achieves its purpose. For example, a method of providing a large number of ejection nozzles for ejecting the pressurized gas, or an injection nozzle is provided. The method of providing a groove part etc. can be mentioned. However, in the present invention, it is essential that the pressurized gas ejected from the pressurized gas ejection port is configured so as not to interfere with the depressurized state inside the fixed drum. As a method therefor, for example, there is a method of projecting from the outer peripheral surface of the fixed drum so that the tip of the injection nozzle or the opening of the groove is slidably contacted with the filter medium. A method of disposing ribs is preferable. By disposing the ribs, it is not necessary to slidably contact the tip of the injection nozzle or the opening of the groove with the filter medium, so that the above-mentioned action can be obtained without scratching the back surface of the filter medium, and also the action of reinforcing the filter medium itself. You can get it at the same time.

[0009]

The filter medium that accumulates and rotates solids is trapped in the filter medium immediately before the tip of the scraping blade because the pressurized gas injected from the pressurized gas jet passes from the inside to the outside of the filter medium. The small solids are pushed out of the filter medium together with the passing gas, so that the filter medium is prevented from being clogged. Moreover, the solid content deposited on the surface of the filter medium is peeled off by the ejected gas, the scraping action by the scraping blade becomes smoother, and it is not necessary to strongly press the filter medium surface like the conventional scraping blade. The risk of scratches and scraping off of the filter media by the scraping blade is extremely small. Therefore, the durability of the filter medium is dramatically improved as compared with the conventional product.

[0010]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a front sectional view of an essential part showing an embodiment of a continuous solid separation device of the present invention, and FIG. 2 is a side sectional view thereof. The apparatus of this embodiment has a fixed drum 1, a rotary filter body 2, a storage tank 9 for storing a solid-liquid mixed fluid 10, and a scraping blade 8 as main components. The fixed drum 1 has a fixed shaft 11 whose one end is fixed by a support leg 13.
, And the other end is fixed by a support leg 14 and is fixed by a communication pipe 12 connected to a negative pressure device (not shown). A large number of ventilation passage holes 4 are bored in the cylindrical portion of the fixed drum 1.

The rotary filter body 3 is provided with a cylindrical filter medium 2 which is concentric with the fixed drum 1, and is fitted and slid on the fixed drum 1.
The rotary filter body 3 has a pulley 15 arranged at one end thereof,
This portion is rotatably attached to the fixed shaft 11. The pulley 15 is driven by a drive device (not shown), and as the pulley 15 rotates, the filter medium 2 also rotates together with it.

In this embodiment, the filter medium 2 is made of a metallic non-woven fabric, the filter medium 2 is cylindrically held by a reinforcing porous plate can body 16, and the wire mesh can body 16 slides on the fixed drum 1. It is reinforced by a large number of moving ribs 17. Rib 1
7 are arranged in parallel in the longitudinal direction inside the metal mesh-like can body 16 at a predetermined interval. Sealing materials 19 for sliding the fixed drum 1 to seal the inside and outside of the filter medium 2 are attached to both ends of the filter medium 2.

A storage tank 9 for storing the solid-liquid mixed fluid 10 is arranged below the filter medium 2, and the solid-liquid mixed fluid 10 is supplied from a supply port 18.

By depressurizing the inside of the filter medium 2, the aspirated solid-liquid mixed fluid is separated by the filter medium 2 into a solid component and a liquid component. Of these, the liquid component passes through the filter medium 2 and further through the ventilation liquid passage hole 4 and is sucked into the fixed drum 1,
It is discharged to the outside of the system through the communication pipe 12 and the negative pressure device.

On the other hand, the filtered solids are deposited in layers on the surface of the filter medium 2 to form a cake 20, which is the filter medium 2.
Is moved into the air as it rotates, and the contained water is sucked and removed together with the air. The cake with reduced water content is scraped off and removed from the surface of the filter medium by the scraping blade 8.

The fixed drum 1 is provided with a groove 5 as a pressurized gas ejection port which is partitioned from the inside by a partition wall 6.
A pipe having a large number of injection nozzles 7 connected to a pressurizing device (not shown) is disposed in the groove portion 5. The groove 5 is oriented toward the vicinity of the scraping blade 8 and opens. Fixed drum 1
In the cylindrical portion of the above, the ventilation liquid passage hole is not bored before and after the rotation direction of the groove portion. The portion where the ventilation passage is not drilled is provided in the front of the groove portion 5 in the rotation direction with a width substantially the same as the gap between the ribs 17, and behind the groove portion 5 in the rotation direction the liquid of the solid-liquid mixed fluid 10 is provided. It is provided to a position slightly above the surface.

Adjacent ribs 1 arranged on the rotary filter body 3
Of the space partitioned by 7 parts, the space of the portion where the groove portion 5 is open is in a pressurized state, and the pressurized gas in this portion is configured to hardly flow into the fixed drum 1, The pressurized gas passes through the filter medium and is ejected to the outside. Along with the flow of the passing gas, the fine solids captured in the filter medium are pushed out, so that the clogging phenomenon is prevented. Further, the gas ejected to the outside acts to separate the cake 20 accumulated on the surface of the filter medium from the surface of the filter medium, and the scraping blade 8 can remove the cake 20 more easily and efficiently.

[0018]

According to the apparatus of the present invention, the pressurized gas ejection port opened so as to be directed near the scraping blade is disposed inside the rotating cylindrical filter medium, so that the inside of the filter medium is exposed to the outside. The gas is ejected by passing through, and the fine solid content trapped inside the filter medium is pushed out to the outside to prevent the clogging phenomenon of the filter medium. For this reason, the durability of the filter medium becomes dramatically longer than in the conventional case. In addition, the solid content that is deposited and dehydrated on the surface of the filter medium is peeled off from the surface of the filter medium by the gas ejected to the outside of the filter medium immediately before being scraped by the scraping blade. There is almost no scratch left and it can be performed very efficiently.

Therefore, since the continuous solid-liquid separation device of the present invention is excellent in the durability of the filter medium, it is possible to perform continuous operation for a long time or a long time, which is not possible with conventional products. Therefore, the device of the present invention is extremely excellent as a solid-liquid separation device for continuously separating a solid content and a liquid content from a solid-liquid mixed fluid, and is extremely useful industrially.

[Brief description of drawings]

FIG. 1 is a front sectional view showing a main part of an embodiment of a continuous solid-liquid separation device of the present invention.

2 is a side cross-sectional view of the device of FIG.

FIG. 3 is a perspective view showing an example of a conventional solid-liquid separation device.

FIG. 4 is a side sectional view of an essential part showing an example of a conventional solid-liquid separation device.

FIG. 5 is a front sectional view showing an example of a rotary filter body of a conventional solid-liquid separation device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Fixed drum 2 Filter material 3 Rotation filter body 4 Aeration liquid passage hole 5 Groove part 6 Partition wall 7 Injection nozzle 8 Scraping blade 9 Storage tank 10 Solid-liquid mixed fluid 11 Fixed shaft 12 Communication pipe 13, 14 Support leg 15 Pulley 16 Perforated plate can Body 17 Rib 18 Supply port 19 Sealing material 20 Cake 21 Filtering material 22a, 22b Flange 23a, 23b Side plate 24 Rotating shaft 25 Hollow rotating shaft 26 Pulley 28 Spring 29 Solid content 30 Container 31 Belt 32 Drive wheel 33 Speed reducer 34 Motor 35 Pipe 36 Suction pump

Claims (3)

[Claims] 1. An apparatus for continuously separating a solid content and a liquid content from a solid-liquid mixed fluid containing contaminants, wherein a stationary drum having a large number of ventilation liquid passage holes on a cylindrical outer peripheral surface is provided.
A rotary filter body having a cylindrical filter medium is fitted and slidably rotated, and the inside of the fixed drum is kept in a reduced pressure state by a negative pressure device, and the inside of the cylindrical filter medium is also in a reduced pressure state. , The liquid content of the solid-liquid mixed fluid is sucked from the pressure difference, the filter material is passed through the fixed drum, and then the liquid is discharged to the outside of the system, and the solid content deposited on the filter material surface of the rotary filter is scratched. In the solid-liquid separation device for removing by a take-up blade, a pressurized gas jet port for blowing a pressurized gas to the back surface of the filter medium is arranged on the outer peripheral surface of the fixed drum so as to be directed near the tip of the scraping blade. A continuous solid-liquid separation device characterized by being installed. 2. The continuous solid-liquid separation according to claim 1, wherein a large number of ribs which slide on the fixed drum are arranged inside the cylindrical filter medium at predetermined intervals in parallel in the longitudinal direction of the filter medium. apparatus. 3. The continuous solid-liquid according to claim 1 or 2, wherein a portion of the fixed drum having no predetermined vent holes is provided in front of and behind the pressurized gas jet in the rotating direction of the filter medium on the outer peripheral surface of the fixed drum. Separation device.