HYBRID FLUID COOLERS
H2O CONSERVING HYBRID FLUID COOLER
   
 

HXI Range
9 models from 100 to 1000 kW

Principle of operation - operation modes
Combined dry/wet operation mode
In this mode the fluid to be cooled is fed first to the finned coil and then to the prime surface coil from where the cooled fluid exits. Spray water is drawn from the cold water sump and pumped to the water distribution system above the prime surface coil.
By wetting the prime surface coil, evaporative cooling occurs. The spray water falls from the prime surface coil over a wet deck surface, which enhances the evaporative heat transfer. Air is drawn through both the prime surface coil and wet deck sections where it is saturated and picks up heat.
The air is, however, still cold enough to achieve significant cooling within the finned coil which is installed at the discharge above the fan(s). In the dry/wet mode therefore both sensible and evaporative heat transfer are used.
Compared to a conventional evaporative cooler significant water savings can be obtained at peak conditions. At reduced heat load and/or ambient temperatures the evaporative cooling portion, and hence water usage, are further reduced when the flow fed to the wet prime surface coil is gradually reduced. This is accomplished by a modulating flow control valve, which controls the design outlet fluid temperature.
This control arrangement automatically assures maximum use of sensible cooling in the finned coil and minimum use of evaporative cooling in the wet prime surface coil. Heat transfer method and flow control are arranged to achieve maximum water saving in the dry/ wet mode.

Adiabatic mode
The adiabatic mode occurs when the fluid to be cooled completely bypasses the wet prime surface coil. No heat is rejected from this coil and the recirculating spray water merely serves to saturate and adiabatically pre-cool the incoming outside air. In most climates the ambient air still has considerable potential for gaining moisture.
Thus adiabatic cooling of the air results in significantly lower air temperatures which greatly increase the heat transfer efficiency. Compared to conventional evaporative cooling equipment the water consumption is much reduced.

Dry mode
During the dry operation mode the spray water loop is turned off. The fluid to be cooled is fed from the finned coil to the prime surface coil. The modulating flow control valve remains fully open to ensure both coils receive the full fluid flow, hence the maximum heat transfer surface is available.
It is obvious that in this mode no water consumption occurs.

Characteristics

  • combination counter/crossflow design
  • induced draught configuration
  • air entry from one side
  • vertical air discharge
  • aluminium axial fans
  • low pressure water distribution system
  • prime surface hot dip galvanized coil
  • copper / aluminium high density finned coil
  • BACross film fill for cooling spray water cooling
  • V-belt drive

Main features

  • low process temperatures
  • up to 70% water saving
  • 3 operation modes · "no plume" operation
  • high density finned coil in dry air
  • low fan power
  • spacious interior for ease of maintenance
  • reduced sound emission due to low noise fans and water pillows
  • side by side arrangement possible
  • factory built sections for minimum site assembly

Material options
Baltiplus corrosion protection
Baltiplus Corrosion Protection comprises all steel components fabricated from Z 600 galvanised steel with 600 g of zinc per mē coating. Cut edges are protected with a zinc rich paint. All fasteners have a 3-stage protective coating consisting of a zinc phosphate treatment, a zinc rich inorganic resin coating and an aluminium rich organic top coat. The exterior surfaces of the equipment are finished with a coat of polymeric zinc aluminium paint.

Baltibond Corrosion Protection System
The BALTIBOND Corrosion Protection System is applied to individual galvanized steel components prior to assembly. These components are manufactured from Z 600 mill galvanized steel sheets with 600 g of zinc/mē. After manufacturing the components undergo an industrial cleaning and drying pretreatment process. Immediately after the pretreatment the components are electrostatically coated with a dry, polymeric hybrid thermosetting powder. The coated components are then put through a thermally activated curing process during which the powder is fuse bonded to the substrate. Stringent quality control procedures and regular testing during the coating process assure consistent high quality of the protection system. The fasteners used for assembly have a 3-stage protective coating comprising a zinc phosphate treatment, a zinc rich inorganic resin coating and an aluminum rich organic top coat.