A fluid pressure increasing machine (140, 150), comprising: a fluid processing chamber configured to contain a process fluid and including an inlet and an outlet; a first member rotatable about a central longitudinal axis; a motor system mechanically engaged to the first member so as to rotate the member about the longitudinal axis in a rotation direction; a plurality of impellers being fixedly mounted to the first member and exposed to the process fluid within the fluid processing chamber such that when the first member is rotated in the rotation direction the impellers act on the process fluid thereby increasing pressure of the process fluid towards the outlet and a reaction force is imparted on the first member in an axial direction from the outlet toward the inlet; and a first rotating element (256, 756) surrounded by a barrier fluid and fixedly attached to the first member, the rotating element having a higher pressure surface (404, 704) exposed to the barrier fluid at a higher pressure and a lower pressure surface (402, 702) exposed to the barrier fluid at a lower pressure, the difference between the higher and lower pressures acting on the respective higher and lower pressure surfaces generating a force on the first member that at least partially counteracts the reaction force, wherein the difference between the higher and lower pressure is at least partially caused by structures (356, 656) on the first member configured to increase the barrier fluid pressure by rotating the first member; characterized in that the first rotating element is a thrust disk and the structures (356, 656) include a plurality of one of: impellers, vanes, pump rings, labyrinths and grooves on an outer edge of the thrust disk. a fluid processing chamber configured to contain a process fluid and including an inlet and an outlet; a first member rotatable about a central longitudinal axis; a motor system mechanically engaged to the first member so as to rotate the member about the longitudinal axis in a rotation direction; a plurality of impellers being fixedly mounted to the first member and exposed to the process fluid within the fluid processing chamber such that when the first member is rotated in the rotation direction the impellers act on the process fluid thereby increasing pressure of the process fluid towards the outlet and a reaction force is imparted on the first member in an axial direction from the outlet toward the inlet; and a first rotating element (256, 756) surrounded by a barrier fluid and fixedly attached to the first member, the rotating element having a higher pressure surface (404, 704) exposed to the barrier fluid at a higher pressure and a lower pressure surface (402, 702) exposed to the barrier fluid at a lower pressure, the difference between the higher and lower pressures acting on the respective higher and lower pressure surfaces generating a force on the first member that at least partially counteracts the reaction force, wherein the difference between the higher and lower pressure is at least partially caused by structures (356, 656) on the first member configured to increase the barrier fluid pressure by rotating the first member; characterized in that the first rotating element is a thrust disk and the structures (356, 656) include a plurality of one of: impellers, vanes, pump rings, labyrinths and grooves on an outer edge of the thrust disk.