Nowadays the manufacture of high nitrogen steels is made by Pressure-Electro-Slag-Remelting (PESR) units using solid nitrides like silicon nitride as a nitrogen source. Although those high corrosion resistant steels show outstanding properties improvements of the material as well as the production process are possible. This work presents a new slag technology for nitrogen alloying directly by nitrogen gas in a PESR plant. A special additive enables nitrogen pick up in slag. This thereby loaded slag provides nitrogen transport to the liquid metal pool where it dissolves in the molten steel. A very homogenous nitrogen distribution in the ingot can be achieved. The thermodynamic model was verified by experiments at industrial scale. It is possible to produce high nitrogen steels without adding solid nitrogen sources. Furthermore an improvement of the cleanliness as well as an increasing recovery can be obtained. An increase of the process stability can be attained concomitantly.