Misting applied to refrigeration systems

Recent statistics show that in industrialized countries, more than 15% of the electrical energy produced is devoted to cold production (12%) and air conditioning (3%) via mechanical vapor compression refrigeration systems (International Institute of Refrigeration). These figures will undoubtedly rise as a result of growing demand, both for urban air conditioning and for cooling in medium and large retail outlets. The environmental implications of these trends are considerable, making the quest for greater energy efficiency in such systems more than ever at the heart of social, political and economic concerns.

A mechanical vapour compression refrigeration plant inevitably includes a condenser through which the heat drawn from the cold source, plus the compression power, is discharged to the outside environment. See [BE 9 730] and [BE 9 732] on refrigeration machines and [BE 9 742] on industrial heat exchangers.

Technologically, three main types of condenser are used: water-cooled condensers, air-cooled condensers and evaporative condensers. For technological and economic reasons, the use of water-cooled condensers is restricted to a few specific applications. Evaporative condensers (closed or hybrid cooling towers) tend to be reserved for large installations, and although they are energy-efficient, the possibility of water stagnation, plume and biofilm development remains omnipresent, and any failure in their maintenance can lead to serious Legionella problems, seriously hindering their development. In this regard, current regulations have evolved following Decree no. 2013-2015 of December 14, 2014 in its heading 2921 by creating a registration regime (power > 3,000 kW) and a declaration regime subject to periodic inspection (power < 3,000 kW) for evaporative cooling systems, by dispersing water in an air stream generated by mechanical or natural ventilation....