EPA: Drop-out box slag not a hazard

摘要

Minimills won a victory May 17th when the U.S. EPA determined that drop-out box slag (Dobs) produced by EAFs is not covered by the hazardous-waste listing for EAF dust. Minimills must pay to have EAF dust removed and shipped under strict EPA guidelines to authorized landfills."This is both a significant cost-reduction opportunity and reduced liability for our SMA electric-arc-furnace membership," said Thomas Danjczek, president of the Steel Manufacturers Assn. (SMA).Hoods and ductwork capture a significant amount of gaseous fumes and particulates. But they are not designed to remove large chunks of material that may be sucked into the duct connected to the EAF roof. This sometimes caused shutdowns. So melt shops installed drop-out boxes, which are large chambers into which the solidified material falls out of the exhaust stream, separating it from the gases and particulate matter that continue through the ductwork to air-pollution-control devices.