Closed-loop cooling towers house tube-type heat exchangers inside the tower, ensuring cooling efficiency through heat exchange between flowing air, spray water, and recirculating water. As it operates in a closed-loop system, it guarantees water quality remains uncontaminated, effectively protecting the main equipment's high-efficiency operation and extending its lifespan. During lower ambient temperatures, the spray water system can be shut off to achieve water-saving effects. Essentially, a closed-loop cooling tower is a combination of a cooling coil and a wet cooling tower, representing a horizontal evaporative cooling tower where process fluids flow through the tubes while air flows outside, without contact. It is a variation and development of the traditional cooling tower. Water from the tower's bottom storage pond is pumped by the recirculation pump and evenly sprayed down outside the tubes. It does not come into contact with process hot water or refrigerant and the air outside the tubes, forming a closed-loop cooling tower that enhances heat and mass transfer through the spray water.