Is there a technology for recovering energy from compressed gases?
We operate six centrifugal compressors to provide 125-psig air for our processes. The reactors consume oxygen and produce a waste gas stream at a pressure of 45 psig. The composition of the waste gas is mainly nitrogen. The waste gas currently goes through a letdown valve, then is routed through a thermal oxidizer to eliminate hydrocarbons, and then released to atmosphere. A: Several companies can provide turboexpanders that are designed to recover power from pressure letdown stations. In a turboexpander, the compressed gas undergoes isentropic expansion in a single-stage radial turbine. The extracted shaft power is available to drive an electrical generator. Turboexpanders are often used in the hydrocarbon gas processing and petrochemical industries. Turboexpanders are readily available in the 500 kW to 10 MW size range and can be designed to work with hydrocarbons, carbon monoxide, nitrogen, hydrogen or other gases. Turboexpander manufacturers can provide curves for various gas mixtu
