Abstract: Liquid fuel for a power plant is vaporized against a heat-exchange fluid, cooling the fluid. A re-circulation circuit enables cooled fluid to be re-directed back for further cooling, when desired. The cooled fluid is used to cool the inlet air for a combustion turbine. Some of the cooled fluid is periodically directing to the bottom of a stratified tank, from which it can be drawn during times when the need for or value of cooling the inlet air is higher. The fluid is warmed as it cools the inlet air, and may be returned for use in vaporizing additional fuel, or returned to the top of the stratified tank.

Abstract: The present invention is directed to a process for purifying natural gas to provide a liquified natural gas product which is substantially pure methane. In the process, a natural gas feed stream is introduced into indirect countercurrent heat exchange in a first heat exchanger to cool the natural gas to below the dew point of ethane and higher hydrocarbons so as to separate the feed stream into a gas which is substantially pure methane and liquid which contains the ethane and higher hydrocarbons. The liquid/gas mixture is transferred to a separator where the gas occupies the head space of the separator and the liquid occupies the bottom of the separator. A gas fraction is removed from the top of the separator and is introduced into countercurrent heat exchange with liquid nitrogen in a second heat exchanger so as to liquefy the substantially pure methane gas.