USE OF DRI IN CONSTEEL®
An increasing number of Consteel® plants started to use
DRI in addition to scrap. DRI is charged through the EAF
roof from a fifth hole, since charging DRI on the conveyor
would cause reoxidation of the pellets. Operating results
indicate that the overall melting process of a mix of scrap
via Consteel + DRI via roof is even more efficient than the
conventional process of scrap by bucket + DRI via roof.
A much higher productivity (+7%) is observed, for the
following reasons:
` No bucket charge implies a shorter power-off time and
no energy loss because of roof opening.
` The process allows a simultaneous charge of scrap and
DRI right from the beginning of the heat, compared to
the bucket process where a suitable amount of scrap
needs to be melted before feeding DRI – transition
between two different melting steps implying temporary
inefficiencies.
` DRI and scrap simultaneous feeding enhance the arc
coverage typical of the Consteel® process due to DRI high
slag production and CO evolution resulting in improved
slag foaming. Increased arc stability and arc efficiency
are possible through the entire heat resulting in lower
power-on time and lower electric energy consumption.