Ceramic foam filter uses

What are ceramic foam filters

The smelting of aluminum alloy is an important part of the aluminum alloy processing process, which is reflected in the alloying, purification, and refinement technology of the smelting process. The removal of non-metallic inclusions in aluminum alloy melt by flux treatment in the furnace and filtration of foam ceramics outside the furnace has long been an important means of aluminum liquid purification.

The ceramic foam filter is a porous ceramic product with an open porosity of 80% to 90%, a density of 0.3g/cm3 to 0.6g/cm3, a unique three-dimensional network skeleton, and an interpenetrating pore structure. The earliest foam ceramic filter was successfully developed by F.R.Mollard and N. Davison of the American consolidated aluminum company in 1984 and used in the aluminum alloy casting system, and in April 1980, they published their research results at the American Foundry Annual Conference. Since then, foamed ceramic filter materials have been developed and developed around the world. Ceramic foam filter uses is more and more common in the metallurgical industry.

The ceramic foam filter uses

The production of ceramic foam filter uses generally uses a three-dimensional network structure and organic foam plastic with connected pores as a carrier, which is immersed in a special ceramic slurry with thixotropy, and a special rolling process is adopted to make the ceramic slurry. It is evenly applied to the skeleton of the carrier, then dried and cured, and then fired at high temperatures.

The application of ceramic foam filter plates in China's aluminum processing industry has been popularized. There are two main modes of application in the purification of deformed aluminum alloy melts. One is to spray powder with flux in the furnace on the aluminum alloy semi-continuous casting line. The melt is refined and filtered outside the furnace with a foam ceramic plate. The ceramic filter plate is to be replaced every time it is cast. Today, some aluminum processing plants also add launder-type online degassing units before filtering to improve the purification effect. The second is to continuously On the casting and rolling line, the replacement cycle of the filter plate is determined according to the pressure difference before and after the filter plate. As for the size of the filter plate, it depends on the flow rate of molten aluminum per unit of time and the total amount of molten aluminum. The higher the cleanliness requirements, the smaller the selected aperture. Filtration and purification of foam ceramics is the last process of aluminum liquid purification. Before this process, flux powder spraying refining or online rotary degassing treatment has been used, so the particles of impurity phase-hydrogen that have not been removed in aluminum liquid are more fine and dispersed. How to promote the accumulation and growth of impurity phases and hydrogen adsorption in the filtration of foam ceramics is particularly important. The mechanical interception of the "filter cake" effect of foam ceramics alone cannot achieve outstanding results. The new generation of foam ceramic filter material is the mission of our company.

Foam ceramic filtration is the last step in the purification of aluminum melt, and it is particularly important to choose the second generation of foam ceramic filter plates. It should be specially pointed out that it is necessary to prevent the secondary pollution of the melt that may occur in the process of solidification and forming after the aluminum melt leaves the filter box. In this process, the sintered flow tank, front box, distribution plate, and hot cap made of fused silica ceramics with long life, high strength, non-stick aluminum, and good thermal insulation are used, and dehumidified and cleaned in time to eliminate possible pollution sources. , to ensure the cleanliness of the aluminum melt can not be ignored.