Sealing system for steam turbine, and steam turbine

The invention relates to a sealing system (1) for sealing a sealing gap (12) between an outer housing (11) and a rotor shaft (15) of a rotor (14) of a steam turbine (10), having a blocking medium wall (2, 3) for producing a blocking medium area (4) between the rotor shaft (15) and the outer housing (11) in the region in front of and/or in the sealing gap (12), wherein the blocking medium wall (2, 3) can be secured to the outer housing (11). The sealing system also has a blocking medium opening (5) in the blocking medium wall (2, 3) in order to feed a blocking medium (6) from the outside into the blocking medium area (4). The sealing system also has a shaft seal (7) for sealing the blocking medium area (4) from a second area (13, 17), which has a second pressure (P2) that is lower than the first pressure (P1), and a sliding ring seal (8) for sealing the blocking medium area (4) from a third area (13, 17), which has a third pressure (P3) that is lower than the second pressure (P2). The invention further relates