Separation of polymer fiber from shredded carpet pieces involves mixing a second solid rich phase with a water-containing separating solution and a strong acid and the separation of the extracted suspension

摘要

A suspension is taken from a stirring tank containing carpet pieces and a separating salt-containing aqueous solution and centrifuged to produce two solid-rich phases and a fluid phase. The second solid rich phase is mixed with a water-containing separating solution in a second tank. A second suspension is separated into a third solid-rich phase, a polymer fiber-rich phase and a fluid phase. A first suspension is taken from a stirring tank (10) containing carpet pieces and a separating salt-containing aqueous solution and centrifuged (14) to produce two solid-rich phases and a fluid phase. The second solid rich phase (17) is mixed with a water-containing separating solution in a second tank (20) to which an acid stronger than H2CO3 is added. The pH value of fluid in this tank is held at 2-6. A second suspension drawn off is separated (25) into a third solid-rich phase, a polymer fiber-rich phase and a fluid phase.