| 摘要 |
<p>PURPOSE:To restrict wasteful power consumption by ensuring that the generation of hunting between circulation pumps is avoided and a smooth change in the total spray amount of a contact liquid is achieved, and further, that the unnecessarily sprayed amount of the contact liquid is minimized. CONSTITUTION:When all circulation pumps of a second stage are used as circulation pumps 3' for controlling the number of rotations and the total spray amount of an absorption liquid 2 is reduced depending upon the flow of exhaust gas 26 and the concentration of sulfure oxide contained in the flow, the number of rotations of all the circulation pumps 3' is reduced by the number of rotations equivalent to almost one of the total number of units of the circulation pump 3' from a constant operating state. After this reduction procedure, the number of rotations is restored to a constant operating state. In addition, one of the circulation pumps 3 of a desired stage structure is stopped from a constant operating state, and for the rest of operation, the same sequence of steps is repeated, so that the desired number of the circulation pumps are caused to stop. On the other hand, if the total spray amount of the absorbed liquid 2 is to be increased, the operation contrary to the above sequence of steps should be performed to allow the desired number of the circulation pumps to operate.</p> |
