Patent ID: 8741014

Claim:
A multi-stage steam-water separation device provided with, in two stages, a steam-water separator, comprising: a cylindrical riser, into which a gas-liquid two-phase flow composed of a mixture of steam and hot water is introduced, which is provided for each of the steam-water separator of a first stage and a second stage; a downcomer barrel which is provided for each of the steam-water separator of the first stage and the second stage, the downcomer barrel of the first stage is arranged so as to surround the periphery of the riser of the steam-water separator of the first stage and the downcomer barrel of the second stage is arranged so as to surround the periphery of the riser of the steam-water separator of the second stage; a first swirl vane which is provided within the riser of the steam-water separator of the first stage, and which causes the gas-liquid two-phase flow to rise while swirling, and a second swirl vane which is provided within said riser of the steam-water separator of the second stage and which causes the gas-liquid two-phase flow which has passed through the first swirl vane to rise while swirling at a speed higher than that provided by the first swirl vane, wherein in the steam-water separator of the first stage, on a downstream side of the first swirl vane in the riser, there is provided an inner cone formed with a diameter gradually increasing towards the downstream side.