Nucor Tuscaloosa Lime Injection System Installation

Nucor Tuscaloosa Steel Inc., located in Tuscaloosa, Alabama, USA has installed one (1) PTI Prolime^TM injection system to supply lime to their 150 ton (136 metric tonne) twin shell EAF. The PTI Prolime^TM injection system eliminated the need to add lime to the belt conveyors that bring DRI to the EAF roof.  Eliminating the lime from the belt conveyors reduced lime dust in both the EAF and LMF work areas and allowed the DRI feed rate to the EAF to be increased.   PTI supplied the engineering and layout design for the material supply, transport line and EAF sidewall panel modifications.  PTI supplied one (1) 250 cuft (7 m³) injection vessel with two (2) outlets.   The injection vessel is capable of holding up to 12,000 lbs (5440 kg) of lime supplied from two separate silos.  Each silo (one containing hi-cal lime and one for dolo-lime) was fitted with a screw conveyor to move material from the silo to the injection vessel.  Screw conveyors were chosen to allow precise addition of the hi-cal and dolo lime to the injection vessel.  The twin shell EAF process allowed PTI to install one (1) injection vessel with two (2) outlets since the lime is only injected to the operating shell.