Turbo expanders TG converts the shaft power into electrical energy. The expander speed is reduced through an epicyclical gear box to 3000 or 1500 rpm (50 Hz), 3600 or 1800 rpm (60 Hz).
Due to very high efficiency and constant shaft speed (stabilized by electrical frequency), these units are very reliable and energy efficient. Selected when a booster compressor is not adequate for the process or when recovered electricity can be sold at high cost. TGs are very popular in countries where electricity cost is high or where government promotes energy recovery (India, South-Africa, Middle-East).
Usual gases handled: air, nitrogen, or waste gas from air with high oxygen content possibility (sour) natural gas, H2 & CH4 mixtures, LNG, NGL, LPG.
|Power||up to 15 000 kW|
|Pressure||up to 200 bar|
|Flow||up to 2.5 million Nm³/h (550 kg/s)|
|Expander temperature||from - 270 °C to + 200 °C|