PURPOSE: To reproduce the titled filuid through purification and concentration by flocculating and settling ferromagnetic oxide particles in dilute water base magnetic fluid from which sludge is removed, and obtaining dehydrated cake through centrifugal separation and collecting a supernatant as clarified liquid after neutralization.
CONSTITUTION: Sludge in polluted dilute water base magentic fluid is separated by using a centrifugal separator. A flocculant is added to the resulting magntic fluid and its pH is adjusted to about 2W3, thereby flocculating ferromagnetic oxide particulates. Then, a supernatant and deposit are separated and the deposit is treated by the centrifugal separator to obtain dehydrated cake of ferromagnetic oxides. An alkali solution is added to this cake for neutralization, and a surface active agent is added at need and dispersed to reproduced concentrated water base magnetic fluid. The supernatant, on the other hand, is neutralized by alkali and the deposit is separated and collected as a clarified liquid to be circulated as washing water.
CHIHARA KOUSEI
YAMASHITA SUKETADA
