KR20020038655A - the manufacturing method of the ceramic filter - Google Patents

Abstract

PURPOSE: A method for manufacturing porous ceramic filter that is suitable to high temperature over 650°C and high pressure conditions is provided. CONSTITUTION: The method includes the steps of (i) mixing clay 45-60wt.%, sawdust 40-55wt.%, diatomite 1-5wt.%, water 40-50%, PVA 1-10,% for more than 2 hours to prepare a mixed slurry; (ii) dipping a nonwoven fabric sheet in the slurry to immobilize ceramic solution to the nonwoven sheet; (iii) drying the ceramic-applied nonwoven fabric sheet while blowing hot wind for over 3 hours within a temperature range of 30 to 90°C; and (iv) sintering the dried nonwoven fabric sheet in an electric furnace where the temperature of the furnace is elevated at a rate of 3°C/min to 200°C, at a rate of less than 1°C/min in the temperature range of 200 to 450°C, and kept for more than 2 hours in the temperature range of 1100 to 1,300°C.

Description

The manufacturing method of the ceramic filter

In the manufacture of the ceramic filter of the present invention, the fibers of nonwoven fabric are precipitated in a ceramic mixture having a slight viscosity to be applied to each of the filaments of the nonwoven fabric, and dried at 30 ° C. to 90 ° C. for at least 3 hours, and this is 1,100 ° C. to 1,300. Sintering at 占 폚 produces a low weight ceramic filter with high porosity.

At this time, depending on the purpose of the filter, the slurry mixed with the same physical properties is coated on the surface with a brush or spray and dried and sintered again at 1,100 ℃-1,300 ℃ to form different pores on the inner and outer walls to surface the harmful substances in each industrial process. It is possible to prevent clogging of ceramic filter by processing at high density porosity and low weight filter and high collection efficiency.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the manufacture of porous ceramic filters for the purpose of removing, reducing and separating dust and particulate matter in gas or liquid, i.e. fluids. Maximum filtering effect is achieved.

Various types of ceramic filter walls that protect the problems of current filters, such as heat resistance, chemical resistance, and abrasion resistance, are for making porous ceramic filters having different pore sizes between inner and outer walls.

In the use of filters, there are various waste incinerators, boilers, coal-fired power plants, and coal gasification combined cycle power generation. Dust collection has been carried out using bag filters or electric dust collectors. However, it is difficult to apply due to the low efficiency depending on the process and the filter cloth is mainly made of polymer system, so it cannot be used when the temperature is over 250 ℃.

On the other hand, ceramic filters are excellent in heat resistance and do not need to install a cooling device, which reduces installation costs. In addition, when using a high-temperature exhaust gas as in the case of coal gasification combined cycle power generation, a filter is necessary because the particulate matter in the gas layer may damage the turbine blades. There is no alternative to the filter.

In the case of the conventionally developed ceramic filter, the tube type using ceramic fiber is generally used, but it is most commonly used. However, the filtration efficiency and back pressure characteristics are relatively high, but the manufacturing cost is high, and the ceramic is used for a long time. Due to the deterioration of the fiber, not only the durability of the filter is reduced, but also the filtration efficiency is reduced, and there is a fear that the fiber is included in the exhaust gas and is discharged to generate secondary pollution.

The present invention is to solve the various problems and improve the existing problems by manufacturing a low-weight ceramic filter having excellent heat resistance, chemical resistance, wear resistance, etc. and having a 3D tunnel structure of a deformed cross-section, the nonwoven fabric is sufficient in the ceramic mixture After wet and dry, the first calcined structure is spray-coated on the surface and dried, and then the second sintering is finished to produce a low weight ceramic filter.

In the manufacture of ceramic filters, the pore size of the wall depends largely on the density of the nonwoven fabric, and the rest of the micropores are controlled by the amount of pore-forming agent (carbon, activated carbon, sawdust, salt, naphthalene, etc.) of the mixture. It can be manufactured by adjusting the pore size with a small deviation by selecting it in the range of 0.001-5mm, and can form high porosity of more than 60%, and has a high specific surface area, and adjusts the pore size according to the dust property To prevent clogging and to maximize low pressure loss and high ventilation and collection efficiency.

The present invention relates to the manufacture of porous ceramic filters for high temperature and high pressure, and is used for the collection and removal of dust, soot, waste gas, fume, and VOC generated in each industrial process. The low weight porous ceramic filter for high temperature and high pressure is manufactured by the following method.

Herein, non-woven fabric is used to bind short fibers to the base of WEB or SHEET fiber aggregates with an adhesive without spinning, weaving, or cotton wool, or to make fibers intertwine with thermoplastic fibers, or to entangle the fibers by needle punching or water punching. All sheet-formed products are commonly used, and the materials used include polyester, aramide, polyphenylene sulfide, home-acrylic, polyimide, PTFE, viscose, and natural fiber.

In this test, various types of pore-forming agents (carbon, activated carbon, sawdust, salt naphthalene, etc.) are precipitated and applied to each of the mixed slurries by using clay as a main component when preparing a mixed slurry of ceramic raw materials. Was carried out as follows.

Example 1

①. 45-60% by weight of clay, 40-55% by weight of sawdust, 1-5% by weight of diatomaceous earth, 40-50% by weight of water are mixed, and then mixed with PVA 1-10% by weight and at least 2 hours in a mixer to form a slurry solution.

②. A 300 mm * 300 mm * 12 mm high nonwoven sheet (SHEET) is precipitated in the slurry solution and squeezed 2-3 times to apply the ceramic slurry solution to the nonwoven fabric.

③. Dry well-coated nonwoven fabric with hot air drying at 30-90 ℃ for at least 3 hours.

④. The dried non-woven fabric is charged into an electric furnace and raised at a rate of 3 ° C./min, slowly increased at a rate of less than 1 ° C./min between 200 ° C. and 450 ° C., and maintained at a temperature of 1,100 ° C. to 1,300 ° C. for at least 2 hours. To finish.

⑤. In the ceramic sheet filter thus sintered, the weight is reduced by 30% before entering the electric furnace and after sintering, and shrinkage occurs by 8%.

⑥. When higher density of micropores and higher collection efficiency are required depending on the application, the slurry solution mixed and mixed together in ① is painted on the surface with brush or spray and dried.

⑦. The dried ceramic sheet is a ceramic sheet filter having pores different from the inner wall and the outer wall when the secondary sintering conditions such as ④ in the electric furnace are completed.

Example 2

①. 45-60% by weight of clay, 40-55% by weight of activated carbon, 1-15% by weight of inorganic binder, 30-50% by weight of water are mixed and mixed with PVA 1-10% by weight for at least 2 hours to form a slurry solution. .

②. Apply 300mm * 300mm * 12mm height nonwoven fabric in the shape of pipe (Pipe) with both ends glued in the vertical direction, settle in slurry solution and squeeze 2-3 times to apply ceramic slurry solution to the nonwoven fabric do.

③. Dry the well-coated pipe non-woven with hot air drying at 30-90 ℃ for at least 3 hours.

④. The dried non-woven fabric is charged into an electric furnace and raised at a rate of 3 ° C./min, slowly increased at a rate of less than 1 ° C./min between 200 ° C. and 450 ° C., and maintained at a temperature of 1,100 ° C. to 1,300 ° C. for at least 2 hours. To finish.

⑤. In this way, the sintered ceramic filter is reduced by 30% before entering the electric furnace and after sintering, and shrinkage occurs by 8%.

⑥. When higher density of micropores and higher collection efficiency are required depending on the application, the slurry solution mixed and mixed together in ① is painted on the surface with brush or spray and dried.

⑦. The dried ceramic pipe is a ceramic pipe filter having different pores in the inner wall and the outer wall when the secondary sintering conditions such as ④ in the electric furnace are completed.

Example 3

①. 45-60% by weight of clay, 40-55% by weight of activated carbon, 1-15% by weight of inorganic binder, 30-50% by weight of water are mixed and mixed with PVA 1-10% by weight for at least 2 hours to form a slurry solution. .

②. A 300mm * 300mm * 12mm high nonwoven fabric is glued on both ends in the vertical direction to form a pipe (PIPE), and one side is closed with a rounded nonwoven fabric to form a tube (TUBE) to settle into the slurry solution. Squeeze 2-3 times to apply the ceramic slurry solution to the nonwoven fabric.

③. Dry the well-coated tubular nonwoven fabric with hot air drying at 30-90 ℃ for at least 3 hours.

④. The dried nonwoven fabric is charged into an electric furnace and raised at a rate of 3 ° C./mim, slowly increased at a rate of less than 1 ° C./min between 200 ° C. and 450 ° C., and maintained at a temperature of 1,100 ° C. to 1,300 ° C. for at least 2 hours. To finish.

⑤. After the sintered ceramic filter, the weight before and after the sintering is reduced by 30% and shrinkage occurs by 8%.

⑥. When higher density of micropores and higher collection efficiency are required depending on the application, the slurry solution mixed and mixed together in ① is painted on the surface with brush or spray and dried.

⑦. The dried ceramic tube is a ceramic tube filter having different pores in the inner wall and the outer wall when the secondary sintering conditions such as ④ in the electric furnace.

The high-temperature and high-pressure ceramic filter manufactured using the present invention can be manufactured in the size required when mounted on the dust collector or the water treatment device, and the pore size can be adjusted according to the intended use.

In addition, it does not require a heat exchanger device through fluid cooling at a high temperature, it is very light with a porous structure of 60% or more, dust collection efficiency is 99.8% or more, dust collection is possible with a filtration speed of 4 times or more than that of a conventional dust filter, and wear resistance Excellent to extend the life of the filter.

Since there is no deterioration or damage of the filter even at high temperature and high pressure, it can be used without separate cooling equipment in waste incinerator, boiler, cement manufacturing process, coal-fired power plant, and coal gasification combined cycle power plant.

Claims (2)

In the manufacture of the ceramic filter, the pore-forming agent, inorganic binder MAP (Mono Aluminum Phosphate), and organic binder PVA (Polyvinyl Alcohol) are mixed with the main ingredients based on various kinds of ceramic raw materials (alumina, titania, diatomaceous earth, silica, etc.) in the same manner as in the embodiment of the present invention. To make a slurry as in the embodiment, and to make a non-woven fabric sheet (SHEET), sheet bending, pipe (PIPE), tube (TUBE), pouches and other various forms using adhesive, sewing, heat fusion, etc. A method of producing by sintering after drying to precipitate in a slurry. In the manufacture of the ceramic filter, as in each embodiment, a slurry mixed with the same kind of raw material as the sintered ceramic filter is coated on the surface of the ceramic filter with a brush or spray, followed by drying and sintering.