| 摘要 |
<P>PROBLEM TO BE SOLVED: To perform appropriate chemical feed to drain without complicating system configurations. <P>SOLUTION: A closed drain system is configured to make each vapor boiler 5 selectively switch drain supply control for supplying drain in a drain tank 6 via a common drain supply line 15 and a branch drain supply line 16 branching from this common drain supply line 15 to each can body 1 and new water supply control for supplying new water in a new water tank 7 via a common new water supply line 35 and a branch new water supply line 36 branching from this common new water supply line 35 to each can body 1, wherein the amounts of chemical feeds by a chemical feeder 9 which performs chemical feed to a common drain circulation part 21 are increased/decreased according to the increase/decrease of the number of the vapor boilers 5 which are performing the drain supply control and the increase/decrease of the operation load of each vapor boiler 5. <P>COPYRIGHT: (C)2012,JPO&INPIT |
