Technology of post combustion

A technology is required which can inject oxygen in the converter just above the slag so that CO can be combusted to  . The supply of oxygen for the post combustion must be well distributed above the slag surface for an efficient combustion of CO. Transfer of the heat to the slag and metal phase is also to be considered.

One possible way is to add several small orifices around the main supersonic nozzle tip. Lance distance has to be adjusted so that oxygen through the orifice is available for combustion of CO to  above the slag surface.

Still another method could be a lance with double flow for oxygen. In the main oxygen lance, a separate oxygen inlet and oxygen control system can be provided which is solely dedicated to post combustion. This design may provide better control of oxygen for post combustion without affecting the oxygen flow through the main lance.

One of main requirement of oxygen flow for post combustion is that velocity and angle of oxygen flow should be low to avoid the refractory wear. Nozzle diameter, angle of oxygen flow and location of nozzle are the principle design issues.