Assimilating the slag-metallic bath interface which is an electric dou
ble-layer and using the mKdV(+/-). equations, it is concluded that the
oscillations of this interface are of the ''cnoidal'' type. The vario
us oscillation modes (non-dispersive waves, wave packets, solitons, an
tisolitons, soliton packets) are obtained as degenerations of the ''cn
oidal'' oscillations. Some considerations on practical applications im
portance are given.