- Dry air coolers
However, this has become increasingly impractical and expensive; water metering, effluent charges and a need to be independent from disruptions to mains supplies by drought or utility failure make the purchase of an industrial cooling system an essential, attractive and economical proposition.
Air blast water coolers, otherwise known as dry air coolers, are the most cost effective way of cooling process water. They are able to cool water to within 3°C of ambient, but it should be noted when designing or specifying those units that the greater the approach temperatures (difference between ambient and water leaving temperature) the more economical they become.
Although the cost of a dry air cooler can be greater than an evaporative cooling tower, the maintenance costs are minimal.
Air blast coolers have an added advantage over open circuit evaporative cooling towers in that the water is contained within a sealed system, does not come into contact with air borne containments and so remains clean. All contact surfaces within F&R’s air blast coolers are non ferrous so providing the external pipework is also of non ferrous material, the water will remain clean and uncontaminated.
Dry air coolers can be supplied as a boxed unit (one assembly supplied with heat exchanger, pump, tank and all necessary controls) or as a free standing heat exchanger, fan and motor assembly with pumps, tanks etc., being supplied separately by the supplier or end user.
There are many options available for this range including fan stage control, fan speed control, a variety of materials of construction including stainless steel and all copper, plus a variety of pump and tank systems to suit specific customers’ requirements. A further option is slow speed fans to give low noise levels.
Whilst dry air coolers will only cool water to within 3°C of ambient, there is a further option which allows this form of cooling to achieve water off (water leaving the system) temperatures as low as to within 5°C of wet bulb ambients. This is known as an adiabatic system, where in higher summer ambients a fine mist of water is sprayed on to the heat exchanger surface reducing the air temperature on the cooling coil. Adiabatic systems are complete with an ultraviolet light water treatment system so again no requirement for chemical water treatment but with the advantage of water temperatures being below dry bulb ambients.
Applications for air blast water coolers, dry air coolers and adiabatic systems are anywhere a process requires cool clean water such as induction furnaces, hydraulic cooling, compressors, quench tanks, printing machines, vacuum pumps and many others. In some instances it will be necessary to install the dry air coolers externally although extra care should be taken to avoid frost damage during the winter.
F&R Products specialise in the specification, manufacture and installation of cooling systems including dry air coolers and can advise on the most appropriate solution for your needs.