JPS6253742A - Catalyst filter - Google Patents

Abstract

PURPOSE:To certainly collect the component to be removed in gas, by supporting a catalyst to the surface of a filter base material formed by weaving a heat- resistant fiber based on a glass fiber containing 90% or more of a silica component or a metal fiber. CONSTITUTION:Several thousands of heat-resistant fibers with a diameter of several mu - several 10mum based on glass containing 90% or more of a silica component, alumina or titania or metal fibers are collected to form one yarn. This yarn is formed into a fabric having constant openings and 10-20 sheets of these fabrics are further superposed to form a catalyst filter element. The metal fiber used here is a nichrome wire (JIS-NCR) or a ferrochrome wire (JIS-PCR) and the wire diameter of said wires is 50mum or 10mum. The alumina fiber used here is a filament with alumina content of 95% or more and a diameter of 20mum or a filament with alumina content of 80% and a diameter of 12mum.

Description

Detailed Description of the Invention (Industrial Field of Application) The present invention relates to a catalyst-supported filter, and in particular, it can be applied to organic solvent vapor, paint mist in paint spray booth exhaust gas, tar mist in epoxy paint baking drying oven exhaust gas,
The present invention relates to a catalytic filter that can be applied to treat exhaust gas containing soot (carbon dust, particulate), etc. in diesel vehicle exhaust gas.

(Conventional technology) Conventional exhaust gas treatment equipment uses a catalyst system, but it only treats steam and gas, and if there is dust or mist (solid or liquid), it cannot be treated. Even if this dust/mist is flammable, it cannot be treated. For example, in the case of nicotine tar or soot from cigarettes, it is impossible to treat it by first filtering it with a filter, washing it with water, or using a cyclone. We had no choice but to use various types of eluminators, such as vacuum cleaners and electrostatic precipitators. All of these pretreatment agents and pretreatment devices require replacement or regeneration.

On the other hand, many conventional catalyst carriers were of parallel flow type, such as pellet type (granular) or honeycomb type (honeycomb shape), so as shown in Figure 3, for example, when exhaust gas from a diesel car (Pass or truck) comes, The current situation is that soot cannot be filtered, so it simply passes through, and the paint mist (fine particles) in the spray exhaust gas from paint coating adheres to the catalyst surface and loses its performance.

Additionally, various types of filters themselves have the ability to act as filters, but while regular filters filter out fine particles, they cannot process them, so they accumulate. Eventually, it becomes physically clogged and needs to be replaced.

(Problems to be Solved by the Invention) The present invention eliminates the drawbacks of conventional exhaust gas treatment devices, eliminates the need for pretreatment of gas containing flammable dust and mist, and reliably removes components from the gas. It is an object of the present invention to provide a catalyst filter that can capture and easily remove mist adhering to the surface of a catalyst, thereby facilitating maintenance of catalyst activity.

(Means for solving the problem) The present invention supports a catalyst on the surface of a filter base material made of glass fiber containing 90% or more of silica, heat-resistant fiber or metal fiber mainly composed of alumina or titania. A catalytic filter is used.

In addition, the filter base material used in the present invention has a thickness of several μ to several 1 μm.
Thousands of 0μ heat-resistant filaments are put together to form one thread, this is made into a woven fabric with a fixed opening, and 10 to 20 sheets of the same woven fabric are further stacked to create a catalyst filter element.

The method of forming a catalyst on this element is disclosed in Patent No. 84''
According to No. 1653. According to this method, the catalyst component is attached to each of the filaments constituting the element, and a layer having a thickness of 1 μm or less can be formed. Therefore, each filament is not bridged, flexibility can be ensured, and phenomena such as cracking, peeling, and powdering do not occur.

In addition, as the metal fiber used in the present invention, nichrome wire (
, TI8-NCR) and iron chromium lj! (JIB-
FCR) is commercially available, and the wire diameter is 50 pm, 10
There are μm ones. Commercially available alumina fibers include filaments of 95% alumina or more with a wire diameter of 20 μm and filaments of 80% alumina with a wire diameter of 12 pm.

(Example) Heat-resistant glass fiber with a diameter of 9p (990% or more silica) 24
00 (thin threads) to 7,200 threads (thick threads) are combined into one thread, and the ratio of 5 thin threads and 1 large thread in both the vertical and horizontal directions makes a woven fabric with a standard sieve of 14 mesh, and 1 square woven fabric with Impregnated with α25 aqueous solution containing S mol of chloric anhydride and 3 mol of propylene glycol chloroplatinic acid (1005 mol per rice), dried at 200°C for 1 hour, baked at 800°C for 1 hour, and exposed to light for 30 minutes in a hydrogen stream. A filter base material is produced by the treatment, and 14 sheets of the woven fabric are stacked as shown in FIG. 3 to create a wave-shaped catalytic filter element.

The woven fabric terminal is inserted into the mold workpiece and fixed with heat-resistant cement.The dimensions of the element are 6,000 Nm of gas to be processed.
” / At the time of H, the major axis is 1800 yen, the minor axis is 1300 yen,
An oval shape with a width of 500 mm, 200 wave heights, and 14 sheets of catalyst cloth were used.

Such a catalyst filter was used to treat exhaust gas from an automobile body electrocoating paint baking drying oven.

The inlet gas concentration is 1120 ppm of total hydrocarbons and total dust (
(including tar mist) 14. When exhaust gas with a temperature of 540°C and a space velocity of 10α000/hour is treated, the outlet gas concentration is
Removal rate is 911L with Z 4 ppm? %, dust α (1
Great results were achieved with a removal rate of 99.7% at 4W/Nm'.

(Effects of the Invention) By employing the above configuration, the present invention dramatically increases the surface area of the catalyst carrier compared to pellet-shaped catalysts (see Figure 2), making it easier to immobilize compared to powdered catalysts, etc. Even for gases containing dust and mist, the removal rate of harmful components is extremely high, and since the dust and mist are combusted on the catalyst surface, the catalyst has the remarkable effect of sustaining catalytic activity.

[Brief explanation of the drawing]

Figure 1 is a perspective view of a catalyst filter that is one embodiment of the present invention, Figure 2 is a diagram comparing the surface areas of a conventional pellet catalyst, a powder catalyst, and the filter of the present invention, and Figure 3 is a diagram comparing the surface areas of a conventional pellet catalyst, a powder catalyst, and a filter of the present invention. FIG. 2 is a cross-sectional view of a pellet type catalyst carrier and a fly cam type catalyst carrier. Sub-Agent 1) Meifuku Agent Ryo Hagiwara - Sub-Agent Atsuo Anzai Figure 1 Figure 2

Claims (1)

[Claims] A catalyst filter characterized in that a catalyst is supported on the surface of a filter base material made of glass fiber containing 90% or more of silica, or heat-resistant fiber or metal fiber mainly composed of alumina or titania.