BOILER WATER SUPPLY SYSTEM, BOILER INCLUDING THE SAME, AND CONTROL METHOD OF BOILER WATER SUPPLY SYSTEM

摘要

PROBLEM TO BE SOLVED: To prevent low-temperature corrosion of a supply water heating device, to install the supply water heating device while saving a space and suppressing costs, and to suppress lowering of a water level of a drum.SOLUTION: A boiler water supply system includes: a water supply system 21 including a first passage 21a for supplying water exchanging heat with boiler water in a steam drum 11 to an economizer 2 for heating supply water exchanging heat with an exhaust gas from a furnace, a second passage 21b branched from the first passage 21a before the heat exchange with the boiler water, and joining to the first passage 21a at a junction point X while bypassing the steam drum 11, and a third passage 21c branched from the second passage 21b and supplying water to the steam drum 11; a temperature detection portion 24 detecting a water temperature between the junction point X and the economizer 2 for heating supply water; a flow rate adjustment portion 25 for adjusting a flow rate of water flowing to the water supply system 21; and a control portion 26 for adjusting the flow rate adjustment portion 25 so that the water temperature detected by the temperature detection portion 24 reaches a prescribed temperature or higher to prevent low-temperature corrosion of the economizer 2 for heating supply water.SELECTED DRAWING: Figure 2