Used foundry sand is recycled by fluidized bed magnetic separation of iron from the cleaned sand before processing to glass fibers useful for sound and heat insulation, electrical insulation, fireproofing or fiber-reinforcement

摘要

Used sand recycling, by fluidized bed magnetic separation of iron from the cleaned sand prior to use in glass fiber production, is new. Used sands are recycled by mechanical and/or pneumatic pretreatment, mechanical removal of foreign and impurity materials, fluidized bed magnetic separation of iron and processing for glass fiber production. An Independent claim is also included for the use of used sands as fiber glass and/or silicate material substitute in glass fiber production. Preferred Features: The cleaned used sand is fluidized with compressed air, fired and qualitatively and/or quantitatively analyzed prior to mixing with glass batch containing fiber glass and/or silicon dioxide and/or with aggregate materials. The used sand may be clay and/or resin bonded core sand, especially from the cold-box or Croning process, and/or loose bulk sand from core production or from casting processes.