ACR Journal

August | September 2021 ADVERTORIAL 18 Advantages of closed-loop equipment for process cooling Growing sensitivity to water conservation and the ever-increasing cost to maintain mechanical systems are driving interest in closed-loop evaporative cooling technology, says Adam Radford, global product manager - closed circuit coolers, EVAPCO. Volume 7 No.5 It’s a common question during the early design phase of large mechanical systems: “Is open-loop or closed-loop cooling equipment better suited for this project?” When it comes to modern heat-rejection technology, both open-loop and closed-loop cooling equipment provide a distinct set of advantages for the engineer, installer and facility owner. Ultimately, the specific cooling needs of the application, the physical parameters of the installation site, budgetary considerations and environmental goals of the project help determine the type of system that is best- suited and specified. With very real concerns about the higher water consumption of open-loop systems, closed-loop cooling technology is gaining broader appeal every year. When properly designed for an industrial process cooling load, both system types can o er energy e ciency, reliability and longevity. Determining which system is best-suited to a certain application is a task left for the specifying engineer and others who are intimately familiar with the needs of the property. Whether open or closed-loop heat-rejection equipment is specified, be certain to select equipment that is certified by the Cooling Technology Institute (CTI). Open-loop equipment The most prevalent type of large-scale heat-rejection equipment in use today is the open-loop cooling tower. These systems are known for their expansive range in available capacities and configurations, reasonable first cost, and energy e ciency. There are, however, several trade-o s when compared to closed-circuit alternatives. Among the largest compromises with open- loop technology are water consumption and the level of maintenance and water treatment required. With open-loop equipment, process fluid enters the top of the cooling tower and flows over the fill, or heat transfer media. Within the cooling tower, the process water is open to outdoor air and any contaminants present in the atmosphere. Falling from the fill, water collects in a basin before returning to the facility’s cooling loop. Due to airborne pollutants, incoming contaminants from the make-up water supply and the presence of absorbed Adiabatic systems are most effective in hot, dry environments. They use up to 80 per cent less water than traditional evaporative units.