| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an exhaust heat recovery boiler, a combined power genera tion method and a device, capable of keeping steam purity high without provid ing a large-size control valve in a high-pressure high-temperature system of the exhaust heat recovery boiler. <P>SOLUTION: In this combined power generation method, the exhaust heat recovery boiler has superheaters 11, 12, 15, 16, 20, reheaters 17, 18, evaporators 4, 8, 13, and fuel economizers 1, 2, 3, 6, 7, 10. Feed water is heated by the boiler by use of heat of exhaust gas of power generating gas turbine 29 to generate steam, and steam turbines 30, 31, 33 are driven by use of the steam obtained by the boiler. Control of outlet steam temperature of the superheater 20 is executed by water pour like before. Water used as the water pour is not the pouring water of the boiler feed water, but high-purify water condensed by indirectly heat-exchanging the boiler feed water with a steam pipe 41 of an outlet of the low-pressure steam generater 4 is supplied to an superheat steam temperature reducer 47 for use to keep the steam purity high. <P>COPYRIGHT: (C)2004,JPO |
