TREATMENT OF SCRAP

摘要

Uncured rubber scrap may be segregated from metal and fibre contaminants by the method of first embrittling the scrap by immersion in a liquid cryogen, then impacting the embrittled rubber and magnetically removing metal, and then milling the remainder. Gas flotation is used during milling so that particles of rubber and fibre are selectively removed from the mill and subsequently classified by size, whereby most of the fibrous component is segregated from a remainder. The remainder is then worked so as to increase the surface area of residual fibre prior to further segregation of fibre from rubber by gas flotation. The combined milling and flotation procedure may also be used for separating components of other mixtures. Apparatus for embrittling and milling is described.