Okay. Google shows up a few choices when you type in orc expander?
If you are planning to go for a positive displacement type expander, feed gas will most likely have to be sufficiently superheated so you dont have 2 phase conditions at the expander exit. Conversely, you may be low limited to some higher exit pressure for a given superheat in the feedgas. Centrifugal type expanders are tolerant to some extent, to liquid in the expander stream for the larger units, so you can drop the exit pressure more than you can with cheaper positive displacement type units.