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Hydrogen
Decision matrix for choosing the central cooling system. Photo courtesy of Kelvion.
Cascade cooling system loops. Photo courtesy of Kelvion.
It is therefore recommended to start by identifying the most suitable system. The logic diagram below can help with this. The first question to consider is whether water for cooling is available. If not, then a dry cooling system must be selected. If yes, purely wet or adiabatic system can be used, depending on if the cooling water amount is restricted / limited. If not, most probably a wet cooling tower is the best choice. If it is restricted, the next question is which temperature difference to the wet bulb temperature is given. If the temperature difference is around 5 K, an adiabatic system can be realized. If the temperature difference is even lower, the Kelvion cascade cooling system can be the right choice. The cascade cooling system is a combination of a dry cooling and a wet cooling system. It consists of dry air fin coolers and wet cooling towers that are combined via a plate heat exchanger pump skid. Here’ s how it works: During colder conditions, meaning when air ambient temperature is sufficiently lower than the outlet process fluid temperature to be cooled, the system runs only as a closed loop within the ACHE. This enables the size of the equipment to be kept to a minimum and especially the quantity of motors driving the fans. The motors are running under variable frequency drives, affording the lowest energy consumption possible. In warmer conditions, the ACHE run at 100 % capacity and the additional cooling is then provided by the wet cooling tower. Running in a closed loop with a plate heat exchanger, it
32 Heat Exchanger World July 2025 www. heat-exchanger-world. com