METHOD OF OPERATING OPEN TYPE COOLING TOWER IN ICING IN FREE COOLING, AND OPEN TYPE COOLING TOWER USED THEREFOR

摘要

PROBLEM TO BE SOLVED: To effectively conduct cooling even under the condition where icing is generated to some extents in a packed plate in a cooling tower, so as to provide a desired output temperature of circulated cooling water, using the open type cooling tower at an outside-air wet-bulb temperature near to an ice point or less. SOLUTION: A water spray amount is set in response to the outside-air wet-bulb temperature, and rotation of a blower 25 is switched to a reverse direction when the output temperature of the circulated cooling water is elevated to reach to the first target value. When the output temperature of the circulated cooling water starts elevation to reach to the second target value after the output temperature of the circulated cooling water goes down abruptly, during the reverse directional operation of the blower 25, the rotation of the blower 25 is switched to a normal-directional operation. The output temperature of the circulated cooling water goes down abruptly thereafter to reach to a set value. The reverse operation and the normal operation of the blower 25 are repeated as one cycle in every time when a temperature of the circulated cooling water is elevated again in accompaniment to the icing in the packed plate 11 to make the output temperature of the circulated cooling water reach to the first target value, and the output temperature of the circulated cooling water is thereby maintained at the set value or around it. COPYRIGHT: (C)2003,JPO