Method and apparatus for processing vaporous or gaseous fluids

Claim 1

A gas expansion engine apparatus comprising: a first foaming unit for foaming a gas with a foamable liquid to provide a foam thereof, said foaming unit having an inlet arrangement and an outlet, said inlet arrangement including a first inlet conduit for introducing said gas to said first foaming unit and a second inlet conduit for introducing said foamable liquid to said first foaming unit, said outlet being adapted for withdrawal of said foam from said first foaming unit; a first compressor having its inlet coupled to said outlet of said first foaming unit for receiving said foam therefrom and for compressing said foam from a first to a second pressure level to isothermally compress the gas contained in said foam from said first to said second pressure level; a first defoaming unit having an inlet coupled to the outlet of said first compressor for receiving said foam therefrom and for separating said gas from said liquid of said foam while maintaining said separated gas at said second pressure level, said first defoaming unit having a gas outlet configured for independent withdrawal of said separated gas and a liquid outlet configured for independent withdrawal of said separated liquid; a second compressor having its inlet coupled to said gas outlet of said first defoaming unit for receiving said separated gas therefrom and for compressing said gas to adiabatically raise the pressure thereof from said second level to a third level; a second foaming unit coupled to the output of said second compressor for receiving said gas therefrom while maintaining said gas at said third pressure level and for foaming said received gas with a foamable liquid to provide a foam thereof, said second foaming unit having an inlet arrangement and an outlet, said inlet arrangement of said second foaming unit including a first inlet conduit for introducing said gas to said second foaming unit and a second inlet conduit for introducing said foamable liquid to said second foaming unit, said outlet being adapted for withdrawal of said foam from said second foaming unit; a first expansion engine having a foam inlet and a foam outlet, said foam inlet of said first expansion engine being coupled to said output of said second foaming unit to receive said foam therefrom, said first expansion engine allowing said received foam to expand isothermally from said third level to an intermediate pressure level between said third and said first pressure levels to thereby produce engine output power, said gas contained in said foam expanding substantially isothermally; a second defoaming unit having an inlet coupled to said foam outlet of said first expansion engine to receive said foam at said intermediate pressure level and for separating said gas from said liquid of said foam while maintaining said separated gas at said intermediate pressure level, said second defoaming unit having a gas outlet configured for withdrawal of said separated gas and a liquid outlet configured for withdrawal of said separated liquid; and a second expansion engine having a gas inlet and a gas outlet, said gas inlet of said second expansion engine being coupled to said gas outlet of said second defoaming unit to receive said separated gas therefrom at substantially said intermediate pressure, said second expansion engine allowing said received gas to expand adiabatically from said intermediate pressure level to a pressure level close to said first pressure level to thereby produce engine output power.