| 摘要 |
PROBLEM TO BE SOLVED: To provide a feedwater heating system capable of heating feedwater under an optimum condition according to temperatures of a heat source fluid and the feedwater.SOLUTION: Water can be supplied to a water supply tank 3 successively through a waste heat recovery heat exchanger 17, a subcooler 16 and a condenser 13 by a water supply passage 8. The waste heat recovery heat exchanger 17 is an indirect heat exchanger between the feedwater to the water supply tank 3 through the water supply passage 8, and a heat source fluid after passing through an evaporator 15. The subcooler 16 is an indirect heat exchanger between the feedwater to the water supply tank 3 through the water supply passage 8 and a refrigerant from the condenser 13 to an expansion valve 14. Supply of the feedwater to the subcooler 16 can be switched between the supply to the subcooler 16 through the waste heat recovery heat exchanger 17 and the supply to the subcooler 16 without passing through the waste heat recovery heat exchanger 17. |
