System for improving the efficiency of a power plant or the like.

摘要

A device for increasing efficiency of a power plant operated by burning fossil fuel has a boiler for heating a process medium. An inlet line is connected to the boiler for feeding a first process gas in the form of combustion air into the boiler. An outlet line is connected to the boiler removing a second process gas in the form of flue gas from the steam generator. A heat exchanger for heating the combustion air by regaining some of the heat contained in the flue gas is provided. At least one device for preheating the combustion air is connected upstream of the heat exchanger. The device for preheating the combustion air preheats the combustion air with heat energy contained in the process medium which is at a low pressure level. At least one device for transferring a portion of the heat energy, introduced into the combustion air by preheating, from at least one of the process gases to the process medium at a high pressure level is provided. The device for transferring is connected so as to bypass the heat exchanger.