Treatment of contaminated waste residue from recycled paper pulping involves continuous grinding in a hammer mill with simultaneous centrifugal fiber removal through a sieve

摘要

Residue containing fibrous and metallic particles in suspension is fed downwards in a hammer mill with a vertical rotor (2) surrounded by a sieve (7). The hammer elements (5) are non-cutting with increasingly finer clearance downwards to produce fine grinding. Fibers pass through the sieve (7) into an annular space (9), optionally assisted by suction, and are removed separately (11). The remaining materials are removed centrally (12) to reclaim metallic and other usable material. An independent claim is included for a hammer mill equipped for this process, with a sieve fineness to match the fibers to be recovered. The sieve (7) can be constructed in exchangeable sections. Baffles (14) are fitted to control the flow rate.