NOVELTY - A separation apparatus comprises an elongated housing (5) with inner cylindrical surface, a gas stream inlet (15) tangential to housing sidewall (20) to cause the gas stream to swirl within the housing, a gas stream outlet (25) located in upper portion of the housing, and a liquid outlet (35) located below the gas stream inlet and having a liquid outlet valve for maintaining minimum level of liquid within the housing.    USE - For separating liquid from gas stream found in fuel processing and/or fuel cell system.    ADVANTAGE - The apparatus achieves maximum separating efficiency and minimal gas flow pressure drop, increasing the overall system efficiency. The apparatus is compact and can be easily packaged in a fuel processor system or integrated fuel cell-fuel processing system.    DETAILED DESCRIPTION - INDEPENDENT CLAIMS are also included for:    (a) manufacture of separation apparatus by providing an elongated housing with cylindrical inner surface, providing a gas stream inlet on a housing sidewall tangential to the sidewall, providing a gas stream outlet on upper portion of the housing, and providing a liquid outlet below the gas stream inlet;    (b) separation of liquid from a gas stream by directing a gas stream into an elongated housing, causing the liquid within the gas stream to contact and adhere to an internal surface of the housing, allowing a liquid-depleted gas stream to rise up through the housing to a gas stream outlet, collecting the liquid in a lower section of the housing, and controlling the level of liquid in the lower section of the housing so that the liquid level does not drop below a predetermined level; and    (c) a power generating apparatus comprising a fuel processor connected with a combustor for producing hydrogen-rich reformate gas stream comprising water, a first separator connected to the fuel processor for separating water from the hydrogen-rich reformate gas stream, a fuel cell connected with the separator for receiving a water-depleted hydrogen-rich reformate gas stream and for producing electricity and an exhaust gas stream comprising water as products of an electrochemical reaction, and a second separator connected to the fuel cell for separating water from the fuel cell exhaust gas stream, with at least one of the first and second separators in the integrated system being the inventive separator.    DESCRIPTION OF DRAWING(S) - The figure is a side view of the inventive separation apparatus.    Housing (5)    Gas stream inlet (15)    Housing sidewall (20)    Gas stream outlet (25)    Liquid outlet (35)    Level switch (55)