JPH0240211A - Filter - Google Patents

Abstract

PURPOSE:To carry out filtration at high temp. without heating from the outside and to easily heat and burn the combustibles deposited on the filter by forming a filter layer with the woven fabric of a conductive exothermic fiber, arranging an electrode on the two opposing sides of the woven fabric, and electrically heating the fiber itself. CONSTITUTION:A fluid-permeable electrical insulating sheet 1 is interposed between the woven fabrics 1a and 1b made of a conductive ceramic fiber, the obtained laminate is wound on a hollow cylindrical supporting body 3 made of a porous ceramic, etc., to form a filter layer, and the electrodes 5a and 5b are arranged on both ends. A fluid contg. solid particles of carbon, etc., is introduced into the filter to collect the particles in the fluid by the woven fabrics 1a and 1b, and the fluid freed of the solid particles is discharged to the outside from a hollow part 4 through the supporting body 3. The electrodes 5a and 5b are then connected to a power source 6 to energize the woven fabrics 1a and 1b to heat the fiber consitituting the woven fabric, and hence the solid material deposited on the woven fabrics 1a and 1b is burned and removed.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to filters for fluids containing carbon particles and other combustible solids. More specifically, the present invention relates to a filter particularly suitable for filtering fluids at high temperatures and incinerating trapped solids at high temperatures.

[Prior Art] Filtration using a filter is a simple and most commonly used method for removing solid particles from a gaseous or liquid fluid to be filtered containing solid particles. In this method, if the fluid to be filtered is at a high temperature and it is necessary to perform filtration at a high temperature, it is necessary to heat the filter together with the container from the outside. In other words, in high-temperature filtration, unless the filtered solids are removed at a high temperature, the filtration time is short and filter regeneration is difficult. The disadvantage is that there are few The reason for this is that the filtered solids stick to the filter material or the solids fuse together due to temperature changes during the filtration process. ``In such cases, the heating of the filter must be strictly controlled from the outside in order to keep the filtration temperature constant.

In addition, when the filtration temperature is not controlled by heating, it is difficult to regenerate the filter itself, making it disposable. Furthermore, if the solid substance is combustible, the used filter can be regenerated by incinerating it in a combustion furnace or by adding fuel and burning it.

[Problems to be Solved by the Invention] However, controlling the filtration temperature to a constant temperature of mixed acid higher than the maximum temperature, especially 500°C or higher, requires fairly large-scale incidental equipment, especially when filtered solid particles are treated. If unnecessary, removal costs are high and it is uneconomical.

In addition, if the solid material is combustible, if the used filter is burned and recycled, about 150
The temperature reaches a high temperature of about 0° C., and there is a problem that the filter is damaged by such high temperature.

The present invention seeks to provide a novel filter free from such problems.

[Means for solving the problem] The above problem is solved by using a woven fabric mainly composed of substantially continuous conductive heat-generating fibers as a filter layer, and arranging electrodes on two opposing sides of the woven fabric. This is achieved by the filter of the present invention, which generates heat from the 41 miscellaneous materials by energizing the fibers.

The filtration layer in the filter of the present invention is mainly composed of one or more layers of woven fabric made of substantially continuous conductive heat-generating fibers.

As the conductive heat-generating material, conductive ceramic fibers are preferred, but heat-resistant metal fibers may also be used. Examples of conductive ceramic fibers include titanium carbide (TiC), silicon carbide (SiC), zirconia (ZrOz), and molybdenum silicide. Silicon carbide fibers, which are the main component, are particularly preferred because they have excellent electrical properties and heat resistance. It takes m#! i can be advantageously produced industrially, for example, by the method described in US Pat. No. 4,743,411, using a polycarbosilastyrene copolymer as a precursor. When producing this fiber, Ti and Zr are added to the precursor polymer.

B etc. may be introduced.

The thickness of the fibers constituting the woven fabric is suitably about 0.1 to 100[)e in denier per filament. II
It is preferable that the specific resistance of the single fiber is 10<-4> to 10<3 >[Omega].crrr at 500 to 1200[deg.]C. The weave structure can be arbitrarily selected from plain weave, twill weave, double weave, etc., but in consideration of the filtration effect, the opening between the fibers should be 0.1 to 500.
Preferably, the fabric is constructed in microns, particularly from 1 to 50 microns. This woven fabric may be a mixed woven fabric using two or more types of fibers, such as silicon carbide 11
It may also be a woven fabric of 11t and titanium carbide fibers. Additionally, the fabric may contain small amounts of electrically insulating fibers.

In the filter of the present invention, it is preferable that the filtration section be constructed by laminating two or more layers of such woven fabrics. In this case, it is preferable to stack the woven fabrics so that the opening between the fibers in each woven fabric becomes smaller in sequence along the flow direction of the fluid to be filtered.

Furthermore, in the filter of the present invention, one or more layers each of a woven fabric made of the above-mentioned conductive heating fibers and a fluid-permeable electrically insulating sheet can be alternately laminated. In this way, the filtration efficiency and the durability of the filtration layer may be improved by interposing a fluid-permeable electrically insulating sheet.

Such a filtration layer is preferably fixed on a support made of a heat-resistant electrically insulating material, preferably wrapped around the outer circumference of a hollow cylinder of highly fluid-permeable porous ceramic.

A woven fabric made of conductive heat-generating fibers has electrodes attached to two opposing sides, and can generate heat by being energized by connecting it to a power source.

FIGS. 1 and 2 illustrate one implementation of the filter of the present invention.
! Figure 1 shows the front view of Mr. A, and Figure 2 shows the cut I! It is a sectional view taken along AA'.

In the figure, 1a and ib are respectively woven fabrics made of conductive heat-generating ceramic fibers, 2 is a fluid-permeable electrically insulating sheet, and 3 is a hollow cylinder made of a porous ceramic molded body having a void communicating from the hollow part to the outer periphery. It is a shaped support, and at least its outer periphery is made of electrically insulating material. 5a.

5b is a pair of electrodes for passing current through the fabrics 151a and 1b, and 6 is a power source.

The electric conductors 15a and 5b are made of a heat-resistant metal having a lower electric resistance than the fibers constituting the woven fabrics 1a and 1b, and silver, copper, or an alloy thereof is usually used.

In the illustrated example, from the outside, woven fabric 1a, sheet 2, woven fabric 1b
Although the three layers constitute the filtration layer, two woven fabrics may be wound around the outer periphery of the support 3 many times. Further, although the illustrated example has a cylindrical shape, the entire structure may be formed into a flat plate shape so that the fluid to be filtered flows from one side to the other side.

[Function] In the filter of the present invention, a fluid containing solid particles such as carbon is usually introduced from the outside of the surface woven fabric 1a,
Woven fabric 1a, sheet 2. Particles in the fluid are captured by the woven fabrics 1a and 1b while passing through the filtration layer made of the woven fabric 1b, and the fluid from which solid particles have been removed is discharged to the outside from the hollow portion 4 through the support 3. .

Thus, the filter used for filtration was woven fabric 1a.

Stop using the fabrics 1a and 1b before an excessive amount of solid particles are deposited on them, connect the electrodes 5a and 5b to the electrode #A6, and
By passing an electric current through b, the 4II constituting the fabric is made to generate heat to about 1000 to 1200°C, and the heat generated burns and removes the solid particles deposited on the fabrics 1a and 1b.

[Effects of the Invention] The filter of the present invention as described above enables filtration at high temperatures without external heating control, since the uIi fibers of the R cloth constituting the filtration layer generate heat through electricity. Temperature control also becomes easier.

In addition, when filtering a fluid containing flammable solid particles, the combustible materials accumulated on the filter can be heated and incinerated while the filter is still installed in the equipment that generates the discharged fluid, making it easy to recycle. By controlling the supplied current, the regeneration processing temperature can be maintained within a certain temperature range and does not reach extremely high temperatures such as 1500°C, which has the advantage that the filter is less likely to be damaged by high heat during the regeneration processing. be.

[Brief explanation of the drawing]

1 and 2 show one embodiment of the filter of the present invention, FIG. 1 is a front view, and FIG. 2 is a line A in FIG. 1.
-A' is a cross-sectional view. 1a, Ib... Woven conductive heating fiber 753... Porous hollow cylindrical support a 5b... Electrode patent applicant Teijin Ltd.

Claims (7)

[Claims] (1) A woven fabric mainly composed of substantially continuous conductive heat-generating fibers is used as a filtration layer, and electrodes are arranged on two opposing sides of the woven fabric, and electricity is applied to the woven fabric. A filter characterized by a woven fabric that generates heat. (2) The filter according to claim (1), wherein the filtration layer is formed by laminating multiple layers of woven fabric. (3) The filter according to claim 1 or 2, wherein the substantially continuous conductive heating fibers are conductive ceramic fibers. (4) The conductive ceramic fiber has a silicon-carbon bond (-Si
The filter according to claim 1 or 2, which is silicon carbide fiber containing -C-) as a main component. (5) The filtration layer is formed by alternately laminating at least one layer each of a woven conductive heat-generating fiber layer with electrodes arranged on two opposing sides and a fluid-permeable electric insulating sheet. The filter according to any one of claims (1) to (4). (6) The filter according to any one of claims (1) to (4), wherein the filtration layer is formed on a fluid-permeable support made of an electrical insulator. (7) As a conductive heating fiber, the specific resistance of a single fiber is 500
10^-^4~10^3Ω at a temperature of ~1200℃
・Claim (1) to use a material having a value of cm.
The filter according to any of paragraph (6).