The direct cooling of the air by fogging, or evaporative cool pads in a mechanical ventilation package is one way to cool poultry and animals during warm weather.
It is possible to reduce the temperature inside a building’s interior with evaporative cooler pads. They draw in warm outdoor air through a saturated media medium. The pad medium absorbs water and cools it. The wet-bulb temperature, or the difference between air temperature (dry bulb), and air wet bulb temperature, determines how much cooling is achieved. Summer daylight wet-bulb depression levels range between 14 and 20 degrees Fahrenheit. Evaporative pads may achieve an efficiency of up to 80% when they measure the difference in temperature from the wetbulb temperature. Modern evaporative cooling pads, when combined with well-designed ventilation, can reduce the incoming air temperature by 5-15 degrees Fahrenheit. This allows for reduced heat stress exposure in livestock facilities, as well as enhancing greenhouse growing conditions.
The cost of purchasing evaporative cooling cushions is substantial. It is also expensive. Below are some guidelines to help with routine maintenance. Following these guidelines will usually result in many additional years of use before replacement pads will be required. It will also ensure that the pads continue to function effectively while in service.
Important water quality for evaporative systems begins with a pH between 6 and 8. If greater, acidification may be recommended. It is essential to bleed out a portion of the system’s water because salts and minerals accumulate when water evaporates and are left behind in the water. The simplest technique to assure that new water will dilute these mineral concentrations is to bleed off the water. In severe circumstances where insufficient bleed-off is given, deposits will form on the evaporative pad’s surfaces. These reduce the efficiency of evaporation. How much should be lost? Follow product guidelines, or just begin with 1 gallon/hour per foot of length.
Instance: for a 50-foot-long 6 “Start with a pace of 75 gallons per hour for a 6-foot-tall, 6-inch-thick pad. It is simple to verify that 75 gallons per hour will fill a 5-gallon pail in 6 minutes and 15 seconds. Reduce leakage with softer water and enhance it with harsher water. The bleed-off discharge must be regulated, such as by routing it to the site’s surface drainage system.
Additionally, ensure that there are no dry sections when the system is operating. The flow to the pads should be sufficient to uniformly wet the entire pad. Standard values are around 0.375 gallons per minute per foot of pad. If the system becomes contaminated with scale or algae, the distribution pipe’s perforations can become clogged.
Observe for algae. Algae is detrimental to pad media; as it accumulates, it increases the airflow resistance of the pads and decomposes the cellulose pad material. Strategies to control algae include:
a) Chemical treatment of waste (see below)
b) Prevent direct sunlight exposure to the pads and, if present, the sump region.
c) Ensure that the pads are completely dry once every twenty-four hours. This can be achieved in a variety of methods, including setting the ventilation controller to only activate the system when the temperature is greater than the nighttime temperature or putting the system on a 24-hour timer to shut it down for a few hours in the early morning.
Watch for scale accumulation. If present increases the rate of blood loss.
Watch for the presence of algae. Adjust daily drying time and examine chemical treatment procedures if observed (below).
Clean any system filters that are present.