Turbomachine assembly

A turbomachine assembly comprising:

• a single shaft;
• a radial gas expander supported on the single shaft between at least one first bearing and at least one second bearing, the radial gas expander comprising at least two radial stages coupled via an interstage path, the at least two radial stages including a high pressure stage and a low pressure stage, a plurality of movable guide vanes comprising a first set of movable guide vanes in the high pressure stage and a second set of movable guide vanes in the low pressure stage, a plurality of struts included in the interstage path configured to guide a gas flow from the high pressure stage to the low pressure stage;
• and
• a compressor supported on the single shaft in an overhung position adjacent to at least one of the first or second bearing, the compressor including a plurality of movable inlet nozzles,
• wherein the movable inlet nozzles and the movable guide vanes are configured to permit varying operating points of the radial gas expander and the compressor, respectively, such that the operating points of the radial gas expander and the compressor are varied independently from one another without needing to differentiate the relevant speeds enabling the single shaft to be used for both the radial gas expander and the compressor,
• wherein an operative gas of the radial gas expander is different from a process gas of the compressor, and
• wherein at least a seal is provided on the single shaft between the compressor and the radial gas expander to separate the operative gas of the radial gas expander from the process gas of the compressor.