Patent ID: 8807053

Claim:
A heat exchanger of a supercritical once-through circulating fluidized bed boiler having a furnace and a boiler steam cycle, said heat exchanger comprising: a first heat exchange chamber and a second heat exchange chamber arranged in connection with the furnace of the supercritical once-through circulating fluidized bed boiler, the first heat exchange chamber comprising a final superheater of the boiler steam cycle of the supercritical once-through circulating fluidized bed boiler and the second heat exchange chamber comprising a final reheater of the boiler steam cycle of the supercritical once-through circulating fluidized bed boiler; a first inlet channel for introducing hot solids from a particle separator of an external circulation of the supercritical once-through circulating fluidized bed boiler into the first heat exchange chamber, which is provided with first means for fluidizing solids; a second inlet channel for introducing solids into the second heat exchange chamber, which is provided with second means for fluidizing solids; a first discharge for removing a first portion of cooled solids from the first heat exchange chamber to the second inlet channel; a second discharge for removing cooled solids from the second heat exchange chamber to the furnace of the supercritical once-through circulating fluidized bed boiler; and an inlet for introducing hot solids from an internal circulation of the furnace of the supercritical once-through circulating fluidized bed boiler directly to the second heat exchange chamber.