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IThe main purpose of a heat recovery system is to replace primary energy in an economically profitable way. Heat is recovered from the exhaust gases and cooling system allowing increased efficiency of the system. Within the recovery system, a heat transfer fluid is circulated. If this fluid circulating in the recovery system is likely to be opposed to frost, we recommend the usage of a heat transfer fluid rather than water with corrosion inhibitors, such as Zitrec AC.

Typical dosage rates for Zitrec LC are 35-40 % . Or use Freezium -15°C to -25°C, or Zitrec S -25°C. When no frost protection is required, use Zitrec AC

The benefits of heat recovery
Recovering heat gives many benefits in different areas :

Heat recovery improves the quality of the environment by reducing the primary steam consumption, in addition to reducing droplet and mist formation and removing a major part of exhaust air moisture.
Recovered heat replaces primary energy resulting in a cost savings.
Heat recovery reduces fossil fuel energy consumption translated directly into less air pollution.
The process of heat recovery is more closed, as evaporated water is returned to the system, resulting in less water consumption and less water load to the environment.
Water vapour is condensed from the exhaust air leading to reduced exhaust plume formation.
Payback is very rapid - between six months and 3 year - but varies from the system and application.

Applications of heat recovery

Heat-recovery can be used either in residential projects, commercial or institutional buildings with multiple showers, or industrial applications with large, continuous flows of hot water, such as clothes washers.

Heat can be recovered either there where hot water drain flow occurs at the same time as hot water supply flow, such as multiple showers or industrial process water systems. Or, when the hot water drain and supply flow is not simultaneous, the recovered heat is added to the hot water tank. Examples are baths, sinks and laundries.

Milk cooling
A very specific application for heat recovery is milk cooling. To maintain milk quality, milk must be cooled from about 39° C (cow body temperature) to 3° C for safe storage. Milk is normally cooled by a refrigeration unit acting as a heat pump moving heat from the milk to a sink (air or water). The heat energy could be 'dumped', or it can be transferred to water using a water-cooled condensing mechanism or a milk precooler leading to substantial savings on water heating energy costs. The recovered heat can then be used to preheat water used for sanitizing. Remaining recovered heat can also be released to the air within the milkhouse or directed outside. The challenge is to chose the optimal 'heat recovery system' that will provide only the warmed water needed and with a reasonable payback.

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