| 摘要 |
To achieve a downsized drain tank without reducing an effective drain recovery rate. A closed drain recovery system includes: a steam boiler (2); a closed-type drain tank (4); an air-open-type makeup water tank (7); a steam introduction line (10) for introducing a first flush steam within the drain tank (4) to the makeup water tank (7); a surplus drain introduction line (8) for introducing surplus drain to the makeup water tank (7) from the drain tank (4); and condensing units (33) and (39) provided for the makeup water tank (7), and configured to condense one or both of the first flush steam and a second flush steam by bringing the one or both of the first flush steam and the second flush steam into contact with the makeup water within the makeup water tank (7), the second flush steam being generated from the surplus drain. |
