The degassing purification system is one of the focuses of aluminum alloy research. By reducing the gas content and inclusions in molten aluminum, the purity of molten aluminum is continuously improved, thus improving the overall performance of aluminum alloy. In order to realize the effective recycling of waste aluminum and obtain high-performance recycled aluminum products, the development of molten aluminum purification technology suitable for recycled aluminum is an important work to improve the quality of aluminum melt.
There are many classification methods of aluminum alloy melt purification technology, mainly according to the following three methods:
① According to the processing state, it can be divided into two categories: online and intermittent.
② According to the purification position, it can be divided into two categories: in furnace purification and external purification.
③ According to the purification principle: it can be divided into adsorption purification and non adsorption purification (filtration).
In the 1980s, the bubble flotation method was mainly developed for the purification of aluminum from melts. After years of development, a variety of bubble introduction methods have emerged. From the beginning, single tube was improved to multi tube, from static injection to dynamic rotary injection, degassing refining effect was better and better. At present, snif method, alpur method, RDU method, mint method, heproject method and Lars technology are mainly represented.
The filtration method is to purify aluminum alloy melt through ceramic foam filter or CFF filter box to separate solid inclusions suspended in the melt. The main filtration media include glass cloth, corundum microporous ceramic tube and foam ceramic.
Advanced aluminum processing countries in the world have developed a large number of advanced aluminum alloy purification technology. The bubble flotation method is used in the Adtech on-line degassing purification system, which has been used in most aluminum foundries, and the degassing effect reaches 60%. Adtech provides CFF filter plate and filter box. They are used together to achieve better filtering effect. At the same time, Adtech also provides non-stick aluminum hot top casting parts, which can better control the quality of casting products.