Abstract: A process is described for direct production of cast iron starting from iron bearing ore in an apparatus having two communicating chambers in which to carry out the process, comprising the following operations: pre-reduction and pre-heating to founding point of the iron bearing ore in a first substantially cylindrical chamber; final reduction, carburization and founding of the resulting iron in a second chamber arranged below said first chamber, in which coal and oxygen, injected into said second chamber, provide the reducing gas both in said second and in said first chamber, characterized by the fact that: said iron bearing ore and oxygen are introduced into said first chamber through the side walls thereof, simultaneously but separately, the oxygen being introduced at a speed lower or equal to the speed of introduction of said iron bearing ore; and said oxygen, coal and flux are introduced into said second chamber simultaneously but separately through the side walls thereof and in a manner inclined downward

Abstract: The present invention refers to a method for determination and control of the amount of nitrogen dissolved in metallic liquid phases and to a device permitting, when placed in the steel producing plant and for instance in the tundish or in the continuous casting mold, the determination of nitrogen content directly from the liquid phase. Such a device can point out possible nitrogen pick-up in real-time, thus permitting to immediately intervene.