Commercial buildings and Industrial machinery generate large amounts of heat while processing. And to stay operational, they need continuous heat transfer which is only possible through a heat exchange process. That is where the cooling technology used in cooling towers comes in handy.
Despite being a technology of the 20th century, knowledge about cooling towers is limited. Some people even believed them to be a source of air pollution. Contrary to popular belief, the only thing they release to the atmosphere is vaporous water. Cooling towers help eliminate excess heat used in industrial operations and transfer it out into the atmosphere.
There are different types of cooling technologies available in the market for achieving this process. However, the function remains the same, which is to transfer heat from the system or a facility to the atmosphere via evaporation. These types of cooling towers are defined by how they use water or air to perform heat transfer. Each of these cooling towers is applicable for certain load configuration, which helps tower operators choose the best option available.
These types include mechanical-draft and natural-draft hyperbolic cooling towers:
Natural-draft cooling towers: With hyperbole shaped cooling towers, this cooling technology utilizes shape and pressure to move up the air naturally. Typically located outside the buildings, these cooling towers induce a pressure difference between heated air and the surrounding air. Due to this pressure difference, air enters into the cooling tower while the water doesn’t come into contact with the air, which is only possible with a heat exchanger.
The heat exchanger separates the cooling tower water and cools down from the evaporation water while avoiding contact between the process water and the air. By enclosing the heated air in the chimney, it creates a pressure between heated air and surrounding air which then enters into the cooling tower. Due to their sizes, the capital cost of these cooling towers is a little higher from other alternatives. However, its operating and maintenance cost is low because of the absence of electrical fans.
Mechanical draft cooling tower: While the process is still the same with a mechanical-draft cooling tower, the only difference is the fan in the cooling tower. In this cooling technology, cooling towers use a propeller or centrifugal fan to circulate the air into the tower and move it up and out in the opposite direction of the warm condenser water of the top of the unit.
Due to the evaporation of a small quantity of the water, heat transfer occurs between air and the water. The air will carry the heat through evaporating water from the cooling tower into the atmosphere. It allows the water to cool down from a delta of the high-temperature point to the final temperature.
Unlike natural draft towers, these are enclosed structures and can be located anywhere inside the building. They are much smaller in size than other cooling towers which is why they are mostly used in hotels, hospitals and commercial buildings. Capacity control is also easy in these types of towers since the speed of the fan can be controlled.
Cooling towers are essential for temperature control and cooling in several industries but it may vary in size, shape and type depending on the building’s needs. From big industries like oil refineries and manufacturing plants to a commercial complex, most facilities have a cooling tower as a part of their HVAC system. Based on your business needs, you can easily choose the right cooling technology and cooling tower type which can help you lower cooling costs, minimize downtime, and improve operational efficiency.