SEPARATING MIXTURES BY FLOTATION IN GAS STREAM;PARTICULARLY RECOVERY OF SCRAP RUBBER

摘要

PCT No. PCT/AU80/00017 Sec. 371 Date Nov. 26, 1980 Sec. 102(e) Date Nov. 26, 1980 PCT Filed May 29, 1980 PCT Pub. No. WO80/02672 PCT Pub. Date Dec. 11, 1980.Uncured rubber scrap may be segregated from metal and fiber 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 fiber 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 fiber prior to further segregation of fiber 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.