Jin-Hui Plastics Industrial Co., Ltd.

Design of closed circuit cooling tower

The main function of closed circuit cooling tower is to isolate outside impurities from entering into the cooling pipes. The closed circuit system makes sure that the cooling water is always clean and maintains stable cooling temperature.

The heat exchanger of closed circuit cooling tower divides cooling system into internal circuit system and external circuit system. Internal circuit system is the closed cooling circuit that isolates impurities from outside and offers clean cooling water for equipment use (pure water or tap water); external circuit system utilizes external circulating pump that sprays on internal heat exchanger and indirectly proceeds with heat exchange for cooling water of internal circuit system. And it is effective to solve limescale problem caused from higher mineral concentration through cooling evaporation process. The structure as below:

  1. Cooling tower machine body + External circulating pump = External circuit system
  2. Cooling tower heat exchanger + Internal circulating pump = Internal circuit system
  3. Using “External circuit system” indirectly cool “Internal circuit system”

The interior of the heat exchanger is constructed with metal tubes as conductor. (It may differ for different design) It's sprayed with water for indirect cooling. The dirt will not enter the facility and it will be a closed circuit cooling system. It will not cause limescale either. (Get to know the relationship between cooling tower and limescale).

Comparison between other cooling systems and closed circuit cooling tower

Comparison between

Closed circuit cooling tower and open tower


Closed cooling tower

open tower



No limescale deposits

Limescale block on heat exchanger ,

Mold amd injection molding nozzle

Maintenance cost

Only need to clean one cooling tower

If the price of ten equipment cost 1000USD, clients need to clean ten equipment and cooling tower

Electrical power consumption


Higher electrical power consumption are higher due to

Water consumption

Lower, cooling water in closed circuit

Higher, open tower needs large number of make-up cooling water

Operating cost

Lower operating cose

Higher operating cost

Cooling water Quality

Not being polluted

Easy to be polluted


Benefits after using closed circuit cooling tower

  1. Prevent carbonate calcium limescale from depositing on tube wall
  2. Prevent SiO2 from depositing on heat exchanger
  3. No limescale deposits on cooling system: power fare declining, fuel expense decreasing, maintenance cost lowering; besides, preventing cooler’s temperature from overheating, oil leakage, and meet the cooling temperature effect
  4. Avoid acid-washing cooling pipes, easy to contribute to cracked pipes
  5. Maintain better cooling water quality: PH value, heat conduction rate
  6. No necessity to clean each equipment one by one. Only need to clean cooling tower
  7. The Closed Circuit and Prevent water splashing design. Large number of cooling water decreases, and water cost descends

Contact Jin Hui

Please refer to SCT Closed Circuit Cooling Tower for further information, or contact us by email: This email address is being protected from spambots. You need JavaScript enabled to view it. (Tel: +886-4-2693-7836). Jin Hui professional engineers will resolve your doubts at the first time. Thank you.