EVAPORATOR WITH MULTIPLE DRUMS Russian patent published in 2016 - IPC F22B21/18 F22B1/18 

FIELD: power engineering.

SUBSTANCE: invention relates to heat engineering. Evaporator for a heat recovery steam generator has two horizontal steam drums of a moderate size, one of which is located slightly higher than the other one. It also includes a coil having pipes located in the hot gas flow. Lower drum communicates with inlets of pipes for the coil. Outlets of pipes are connected to the upper drum. Drain line connects the lower part of the upper drum with the lower area of the lower drum so, that water flows from the upper drum into the lower drum. Water, which is mainly in the liquid phase, enters the lower drum through the inlet line and is mixed with water from the upper drum. Mixture flows into the coil. Here some part of it is converted into saturated steam, while the other part remains as saturated water. Saturated steam and saturated water flow into the upper drum, where the steam is released, and water flows back into the lower drum for recirculation through the coil. Due to their moderate sizes the drums can withstand high pressure without excessive walls thickness, and it makes it possible to introduce the evaporator into the working mode with minimum points of delay or without them. Herewith the said two drums provide the retention time and protection corresponding to one drum of a high capacity with significant thickness of the walls.

EFFECT: proposed is an evaporator for a heat recovery steam generator.

15 cl, 2 dwg