Waste heat recovery power generation plant for sintering facility

A waste heat recovery power generation plant to be applied to a sintering facility including a sintering machine and a sintered-ore cooler, the waste heat recovery power generation plant comprising:

• a multi-stage type steam turbine including a high-pressure stage, an intermediate-pressure stage and a low-pressure stage and being joined to a power generator;
• a sintered-ore-cooler waste heat boiler configured to heat condensate of the multi-stage type steam turbine by introducing an exhaust gas of the sintered-ore cooler so as to generate hot water and steam;
• and
• a sintering-machine waste heat boiler configured to heat all of or a part of the hot water generated by the sintered-ore-cooler waste heat boiler by introducing a high temperature part of an exhaust gas of the sintering machine so as to generate steam,
• wherein:
• the steam generated by the sintered-ore-cooler waste heat boiler and the steam generated by the sintering-machine waste heat boiler are supplied to a high-pressure stage of the multi-stage type steam turbine;
• a temperature of the hot water to be supplied to the sintering-machine waste heat boiler is controlled such that a temperature of the exhaust gas at an exhaust-gas outlet of the sintering-machine waste heat boiler is maintained to be higher than an acid dew point;
• the sintered-ore-cooler waste heat boiler includes a first evaporator, a first superheater, a first economizer and a first steam drum;
• the sintering-machine waste heat boiler includes at least a second evaporator, a second superheater and a second steam drum;
• the first economizer is configured to heat the condensate of the multi-stage type steam turbine, and the heated hot water is supplied to the first steam drum and is directly or indirectly supplied to the sintering-machine waste heat boiler;
• and
• steam generated by the first evaporator and the first superheater and steam generated by the second evaporator and the second superheater are supplied to the high-pressure stage of the multi-stage type steam turbine,
• the waste heat recovery power generation plant further comprising a steam extractor configured to generate steam by means of heat of the hot water supplied from the first economizer of the sintered-ore-cooler waste heat boiler and configured to supply the generated steam to the multi-stage type steam turbine,
• wherein hot water discharged from the steam extractor is supplied to the sintering-machine waste heat boiler;
• the steam extractor includes a first stage flasher configured to supply steam to an intermediate-pressure stage of the multi-stage type steam turbine, and a second stage flasher configured to supply steam to a low-pressure stage of the multi-stage type steam turbine;
• the first economizer is configured to heat condensate of the multi-stage type steam turbine and returned hot water of the second stage flasher, and the heated hot water is supplied to the first stage flasher and the first steam drum;
• and
• hot water discharged from the first stage flasher is supplied to the second stage flasher and the sintering-machine waste heat boiler.