Method and apparatus for achieving a high efficiency in an open gas-turbine (combi) process

摘要

Method and apparatus for achieving high efficiency in an open gas-turbine process, in which a supercharger compresses air, which is burned together with a fuel in a first combustion chamber, which is followed by a first turbine, a second combustion chamber, a second turbine, and a preheating heat exchanger, in which primary bleed water vapor coming from the secondary process, or a mixture of the aforementioned water vapor and air coming from the supercharger are preheated. From the heat exchanger the combustion gases go to a waste-heat boiler, in which the secondary-process feed water is vaporized. The combustion gases are expanded in the second turbine to a pressure 0.5 bar lower than that of the surrounding atmospheric pressure. The remaining combustion gases are compressed by a combustion-gas supercharger to the surrounding atmospheric pressure. After the low-pressure turbine the water vapor is condensed in a condenser into water, which is compressed by a pump to a maximum pressure and is preheated and vaporized in the waste-heat boiler. After the waste-heat boiler the water vapor goes to a combined high/medium-pressure turbine, from which a secondary-process primary bleed is taken, which is injected into the gas-turbine process after the preheating heat exchange after the supercharger and/or at the latest to the start of the blades of the first turbine.

主权项

1. Method for achieving a high efficiency in an open gas-turbine (combi) process, in which a supercharger compresses the air required for combustion, which is burned with a fuel in a first combustion chamber, which is followed by a first turbine, a second combustion chamber, a second turbine, a preheating heat exchanger, and a waste-heat boiler, in which secondary-process feed water is vaporized, comprising the steps of:
expanding the combustion gases after the second combustion chamber in the second turbine to the end of the expansion stage, to the minimum pressure of the expansion of the primary process, and to a pressure in the primary process of at least 0.5 bar less than the surrounding atmospheric pressure; condensing and removing water vapor arising in combustion and other water vapor from the negative-pressure combustion gases at the latest after the precooler following the waste-heat boiler; pressurizing the whole final part of the combustion gases containing the nitrogen of the air and carbon dioxide arising in combustion by the combustion-gas supercharger into the surrounding atmosphere and out of the gas-turbine process; condensing the water vapor arising in combustion in the primary process, into a liquid at a pressure lower than atmospheric pressure; taking primary bleed water vapor from the secondary-process turbine and feeding it after the preheating heat exchanger into the gas-turbine process circulation after the supercharger; and bringing an amount of additional water at the same pressure level, corresponding to the secondary-process primary bleed, to the secondary process before the pump.