Method for preparing ceramic filters with hot pressure casting process

Abstract

The invention relates to a method for preparing ceramic filters with a hot pressure casting process. The method comprises steps as follows: alumina powder with proper grain size distribution and paraffin are mixed in a certain ratio, one or more pore-forming agents such as carbon powder, wood chips, aluminum salt, titanium salt, magnesium salt, sodium salt, lanthanum salt, cerium salt and the likeare added according to the size and distribution of required pores, and alumina slurry is configured. Under certain pressure, the slurry is injected into a mold meeting the shape requirement for forming, and various special-shaped filter bodies meeting the requirements are prepared; the bodies are subjected to removal burning, the pore-forming agents are removed, and porous bodies are obtained; the porous bodies are sintered at the high temperature, and the special-shaped alumina ceramic filters are obtained. In the whole process, no special mechanical equipment is required, the pore size anddistribution and the shapes of the filters are controllable, and the method is an ideal process for preparing high-porosity, high-strength and special-shaped ceramic filters.

Description

technical field [0001] The invention relates to a method for preparing a ceramic filter by a hot pressure injection process, Background technique [0002] With the development of society, the environmental pressure is becoming more and more serious, which leads to the gradual increase of the requirements for filtration devices in various fields. Taking metallurgy, machinery, chemical industry, electric power and other industries as examples, the high-temperature dust-laden gas discharged from various industrial furnaces not only has a high temperature (500-1200°C), but also contains a large amount of dust (5-30μm) and corrosion-reducing properties. Gas is one of the main factors causing environmental pollution. Under high temperature conditions, due to the large change in the viscous force of the dust-laden gas, the humidity drops sharply, and the agglomeration of fine particles is greatly reduced, so it is more difficult to separate the particles. The bag type dust collec...

AI Technical Summary

Problems solved by technology

Porous ceramics prepared by extrusion molding have uniform pore shape and pore size distribution, but are not suitable for preparing porous ceramics with a pore size of less than 1mm; traditional methods of adding pore-forming agents to prepare porous ceramics have poor pore distribution uniformity and are not suitable for preparation Products with high porosity; the foaming method adds organic or inorganic pore-forming agents, generates volatile gases through physical or chemical reactions to produce foam, and is made into porous ceramics after drying and sintering, which is not suitable for the preparation of products with through-pore structures; The organic foam impregnation method prepares porous ceramics, and its pore size mainly depends on the pore size of the organic foam, and its products cannot achieve the filtration of tiny particles; the sol-gel method obtains pores through phase change or chemical reaction, and the pore size is nanoscale. low porosity

Due to the limitations of the above process, the obtained pore size and porosity are limited to a certain range, and it is difficult to prepare porous ceramic filters with micron pore size, high porosity, high strength and specific shape.