METHOD FOR REMOVING POLYCHLORINATED DIBENZO- DIOXIN, POLYCHLORINATED DIBENZOFURAN AND ADHERING MATERIAL FROM SECONDARY FIBER

摘要

PURPOSE: To remove the subject compounds and an adhesive material from waste paper, or the like, bringing a cellulose-containing secondary fiber into contact with CO2 or propane under pressure and temperature conditions to be a supercritical fluid or a near supercritical fluid. CONSTITUTION: A cellulose-containing secondary fiber such as waste paper is packed into an extractor 13. Carbon dioxide or propane under pressure and temperature conditions to be a supercritical fluid or a nearly supercritical fluid is fed from a supply source 10 through a conduit 12 to the extractor 13 and brought into contact with the secondary fiber to extract and remove polychlorinated dibenzodioxins(PCDD) and/or polychlorinated dibenzofurans(PCDF) and an adhesive material in the secondary fiber. A gas stream of carbon dioxide or propane is sent from a collector 24 to a conduit 25, passed from a flow meter 26 and a dry test meter 28 and discharged to remove PCDD, PCDF and the adhesive material from the secondary fiber.