JP2798392B2 - Continuous filtration device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Object of the Invention (Industrial application field) The present invention continuously operates on various kinds of slurries such as fine particles for pigments and paints, fine ceramic raw materials, electromagnetic materials, fine particles for food materials and additives, marine fuel, muddy water and the like. It relates to a strainer or filtration device that can be used.

Some of the above application examples are described in more detail. For example, a base film of a magnetic tape incorporates particles having a diameter of 3 to 4 microns or less in order to improve the slip of the tape. However, since the thickness of the base film is small, some lubricant particles have a diameter larger than a predetermined diameter. And it becomes a defect.

When coloring is directly performed by mixing a pigment with the yarn, if the particle size of the pigment is too large, the yarn may have bumps and may not be able to be loomed. In such a case, it is necessary to precisely adjust the particle size of the pigment mixed with the yarn.

Coarse particles in the raw materials of fine ceramics and particles mixed in from the outside will cause defects after firing,
It is important to remove these unnecessary particles from the fine ceramic raw material.

The present invention relates to a filtration device for filtering a slurry as a raw material in the above case so as to contain only particles having a certain diameter or less.

Further, as an example of particularly utilizing the dispersing function, there is reforming of fuel oil. For example, heavy fuel oil C, which is often used for marine fuels, contains sludge such as catalyst residues and polymer substances, and cannot be used as fuel for diesel engines unless sludge is removed. However, since the polymer substance in the sludge can be used as a fuel, it is preferable to disperse the fuel into a fuel. However, clogging of the filter medium easily occurs due to the polymer substance or the like. The present invention relates to a filtration device used in such a case, which performs both dispersion and filtration.

(Prior Art) Conventionally, as an apparatus for performing continuous filtration, an outer chamber and an inner chamber are separated by a cylindrical filter, and a filtration provided with an inlet in the outer chamber and an outlet in the inner chamber. In the device,
There is a filtration device that operates while destroying the cake layer formed on the filter surface by ultrasonic waves.

2 and 3 are a longitudinal sectional view and a transverse sectional view of the ultrasonic filtration device. As shown in FIG. 3, the slurry entering from the inlet 30 is filtered by the filter 31 and exits to the outlet 32. At this time, a cake layer is formed on the surface of the filter 31 by coarse particles or the like in the slurry.
Ultrasonic waves are applied to the cake layer from a horn 34 connected to an ultrasonic vibrator 33 to disperse the secondary aggregated coarse particles forming the cake layer into fine particles and remove the cake layer. Since the filter is rotating, the entire surface of the filter is sequentially cleaned by ultrasonic waves. In order for this device to maintain continuous filtration capacity,
It is necessary that the dispersion and filtration ability by ultrasonic waves exceeds the amount of particles to be collected.

In this case, the dispersing and filtering capacity is determined by the amplitude of the ultrasonic wave, the shape of the horn, the gap between the horn tip and the filter medium, the pressure of the processing liquid, the number of rotations of the filter, and the like. , Particle size and filtration accuracy of the filter.

Although this ultrasonic filtration device has excellent performance, there is still a limit as the particle concentration in the slurry increases.

(Problems to be Solved by the Invention) An object of the present invention is to provide a filtration device capable of performing a continuous filtration operation on a slurry containing hard fine particles or a slurry having a high particle concentration.

B. Configuration of the Invention (Means for Solving the Problems) In order to solve the above problems, the apparatus of the present invention is provided with a filtration chamber provided with a nozzle into which a slurry flows, a slurry reflux outlet, and a filtrate outlet. In a filtration device in which the chambers are separated by a cylindrical filter, the nozzle arranged in a direction to form a flow in one direction around the cylindrical filter, an arrangement to form a strong slurry reflux flow in the direction in the one direction, and A continuous filtration device that includes the slurry reflux outlet having a diameter, and that continuously ejects a high-pressure slurry flow for dispersing the slurry from the nozzle and refluxes the unfiltered slurry through the slurry reflux outlet. is there.

(Operation) The operation of the device of the present invention will be described with reference to the drawings. First
The figure illustrates the operation of the filtration system device of the present invention. The slurry stored in the slurry tank 4 is mixed by the mixer 5.

The mixed slurry is pumped by a pump 6 to a filtration device. At this time, the pressure applied is such that the slurry ejected into the filtration device can cause a dispersing action and a cleaning action on the cylindrical filter.

The pressurized slurry is jetted from nozzles 2 and 3 provided at the tip of the inlet into the filtration device into a chamber 7 (hereinafter, referred to as a filtration chamber) in the filtration device.

Due to the ejected slurry flow, a flow around the filtration chamber 7 is generated. The slurry is filtered while flowing in parallel to the filter surface, and the filtered liquid moves to a chamber inside the cylindrical filter and is discharged from the filtrate outlet 9. The unfiltered slurry exits the reflux outlet 8 and is returned to the slurry tank 4. The device of the present invention is characterized in that the flow of this reflux is stronger than that of a normal filtration device.

At this time, the filtration speed can be adjusted by the differential pressure between the chambers inside and outside the cylindrical filter. This differential pressure can be adjusted by adjusting the valves 10-13. Further, the opening and closing of the valve can be controlled by a microcomputer or the like as an automatic valve.

Further, since the surface of the cylindrical filter 1 is constantly exposed to the flow of the slurry, no cake layer is formed on the filter surface unlike a conventional filtering device. For this reason, long-time continuous operation is possible. Further, even when the cylindrical filter 1 is clogged, the problem can be solved by setting the pressure difference between the chambers inside and outside the cylindrical filter to zero. For example, a valve
If 10 is closed, the differential pressure will be zero.

When the slurry flow ejected from the nozzle is ejected, a shear force due to a rapid change in velocity acts on particles in the slurry, and the particles are dispersed. The high-speed slurry flow ejected from the nozzle causes cavitation, which also promotes the dispersion of particles in the slurry. As described above, the slurry flow ejected from the nozzle creates a flow in the filtration chamber 7 and also performs a strong separating action on the particles contained in the slurry.

In the filtration device of the present invention, the slurry is circulated around the cylindrical filter in the filtration chamber 7, but the slurry reflux outlet 8 is arranged in the direction along the flow and the slurry has an appropriate diameter, so that the Effective as a cyclone,
Among the particles contained in the slurry, the number of returns of coarse particles increases. As a result, the chance of the coarse particles being subjected to the dispersing action increases, so that the dispersing effect of the entire slurry is further improved.

Although two nozzles are arranged in the figure, the number is not limited to this number, and may be an appropriate number according to the size of the apparatus, the viscosity of the slurry, and the like.

(Example) Hereinafter, an apparatus according to an example of the present invention will be described with reference to the drawings. FIG. 4 is a perspective view showing the appearance of the apparatus according to one embodiment of the present invention. In this apparatus, the reflux outlet of the slurry is provided at the upper part of the filtration chamber. The incoming slurry is supplied from the left side of the filtration chamber. Adjustment of the rotation speed of the pump and the filter is performed on the operation panel 14 on the front. The pressure applied to the slurry is appropriately set depending on the type of the slurry, but a pressure of at least 10 kgf / cm ² is generally required.

FIG. 5 is a perspective view of another embodiment of the apparatus in which the reflux outlet is arranged in the direction along the flow.

FIG. 6 is a cross-sectional view of the filtering mechanism. Housing 15
Inside, a cylindrical stainless steel (SUS304) filter 16
Are rotatably arranged.

Circulation occurs in the filtration chamber 18 due to the flow of the slurry ejected from the nozzle 17. A reflux outlet 26 at the top of the filtration chamber 18;
A drain port 27 is provided at the lower part. The drain port 27 is closed during the filtering operation. The slurry is filtered through filter 16 and exits through filtrate outlet 25.
The unfiltered slurry is returned to the slurry tank through the slurry reflux outlet 26.

FIG. 7 and FIG. 8 show an embodiment of the filtration device in which the direction of the slurry reflux outlet is arranged in the direction along the flow. With this arrangement of the reflux outlet, the slurry flowing outside the filtration chamber can easily flow into the slurry reflux outlet.

FIG. 9 is a longitudinal sectional view of the filtering mechanism. The filtration chamber 18 is surrounded by a housing, a cover 19 and the like, and has a closed structure by O-rings 20 to 23. The cylindrical filter portion supported by the bearing portion 24 has a mechanism that can be rotated while maintaining a sealed state. The liquid that has passed through the cylindrical filter 16 exits through the filtrate outlet 25.

C. Effect of the Invention The filtration device of the present invention circulates the slurry using a cylindrical filter while filtering by a parallel flow filtration method, and disperses agglomerates in the slurry in the circulation process, so that the slurry is not finally filtered. The amount of sludge that remains can be reduced. In the apparatus of the present invention, since the slurry reflux in the filtration chamber is strong, sludge is less likely to be accumulated in the filtration chamber as compared with the ordinary cylindrical filter system, and stable continuous operation can be performed even for high-concentration slurry. Further, since the slurry flow ejected from the nozzle has a strong dispersing action, there is an effect that a continuous filtration operation can be performed on a slurry having a wide range of concentration. Further, since the slurry flow ejected from the nozzle creates a strong flow on the filter surface, there is also an effect that the cake layer does not grow on the filter surface as in the conventional apparatus.

[Brief description of the drawings]

FIG. 1 is a system diagram for explaining the operation of the apparatus of the present invention, FIG. 2, FIG. 3 is a sectional view of a conventional ultrasonic filtration apparatus, FIG. 4 is an external view of the apparatus of one embodiment of the present invention, FIG. 5 is an external view of an apparatus according to another embodiment of the present invention, FIGS. 6 to 8 are cross-sectional views of a filtration mechanism of the apparatus of the embodiment, and FIG. 9 is a longitudinal cross-sectional view of the filtration mechanism. is there. 1,16 ... Cylindrical filter, 2,3,17 ... Nozzle, 4 ... Slurry tank, 5 ... Mixer, 6 ... Pump, 7,18 ...
... filtration chamber, 8 ... reflux outlet, 9,25 ... filtrate outlet,
10-13: Valve, 14: Operation panel, 15: Housing, 19: Lid, 20-23: O-ring, 24: Bearing.

 ──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-63-100909 (JP, A) JP-A-61-167912 (JP, U) JP-A-62-114610 (JP, U) JP-A 57- 95214 (JP, U)

Claims (1)

(57) [Claims] A filtration chamber (7) provided with a nozzle into which a slurry flows and a slurry reflux outlet (8) and a chamber provided with a filtrate outlet (9) are separated by a cylindrical filter (1). The filtration device, comprising: the nozzle arranged in a direction of forming a circulating flow along the circumferential direction around the cylindrical filter; and the slurry reflux outlet arranged in a circulating direction along the circumferential direction, A continuous filtration device, wherein a high-pressure slurry flow for dispersing agglomerates in the slurry is jetted from the nozzle and continuous filtration is performed while refluxing the unfiltered slurry via the slurry reflux outlet.