What are the benefits of using a closed-loop cooling system?

One of the most significant benefits of closed-loop cooling is the reduction in water use compared with once-through tap water cooling.

In an open, once-through system, fresh mains water passes through the process before being discharged. Where equipment operates for long periods or requires a high flow rate, this can result in significant water consumption.

A recirculating chiller instead reuses the process fluid within a closed circuit, substantially reducing the requirement for a continuous fresh water supply.

This can support wider water conservation and sustainability objectives while also reducing the costs associated with water supply and disposal.

A recirculating chiller does more than simply provide a source of cool water. It actively controls the temperature of the circulating process fluid.

Maintaining the required fluid temperature can be important where process performance, equipment operation, or repeatability depends on stable thermal conditions.

The chiller should therefore be selected according to the actual requirements of the application, including the heat load, required fluid temperature, flow rate, coolant, and ambient conditions.

Relying on mains water means that the cooling process is dependent on the conditions of the incoming water supply.

A closed-loop chiller provides a dedicated cooling circuit designed around the requirements of the application. This gives greater control over the process fluid and its operating temperature.

It can be particularly useful for equipment where cooling forms an important part of maintaining consistent process conditions.

Because the fluid is contained and recirculated within the cooling circuit, a closed-loop system provides greater control over the coolant used within the application.

This allows a suitable process fluid to be selected according to the requirements and compatibility of the equipment rather than relying solely on the available mains water supply.

The fluid should always be appropriate for the chiller and application.

A closed-loop system can also reduce the amount of cooling infrastructure that depends on a continuous mains water supply.

This can be valuable where water consumption is being reduced as part of environmental initiatives or where continuous once-through cooling is undesirable.

The exact financial benefit will depend on factors such as local water and wastewater charges, operating hours, flow requirements, and the electrical consumption of the selected cooling system. For this reason, ATC does not recommend applying a single savings or payback figure to every application in isolation.

A closed-loop cooling system still needs to be correctly designed and integrated.

The chiller’s pump circulates fluid through the process, while pressure develops as that flow encounters resistance within the customer’s pipework, fittings, and equipment.

When specifying a chiller, ATC will therefore normally ask for information including:

• What is being cooled
• Process heat load
• Required flow temperature
• Required flow rate
• Coolant type
• Any stated pressure requirement
• Ambient operating conditions

Providing accurate information helps us to select a chiller and pump that are appropriate for the application.

A recirculating chiller may be worth considering if your process currently relies on a continuous supply of tap water for cooling, or if you require greater control over process temperature and coolant conditions.

Every application is different, so the cooling system should be selected around the requirements of the process rather than simply replacing the existing water supply on a like-for-like basis.

Contact ATC to discuss your process cooling requirements and find out whether a closed-loop recirculating chiller is suitable for your application.