Based on the expansion project of 1×350 MW unit (Unit 3) in the second phase of a project

this paper analyzes the circulation cooling scheme of the second phase with the first phase which consists of 2×350 MW units(Unit 1

Unit 2) with a set of secondary circulation cooling system and natural ventilation cooling tower (two units with one tower).In case of limited space

this paper innovatively put forward scheme of the second phase which does not build cooling tower

circulating water pump room

circulating water pumps and other cooling facilities

and adopt the use of first phase’s cooling tower

the transformation of the first phase of the circulating water pumps and motors

“three units with one tower”scheme.Through technical and economic comparisons

it was found that this plan is feasible.After the renovation was completed

the circulating cooling water system of the unit operated well under all working conditions throughout the year.