What Is A Closed Circuit Cooling Tower?
Also known as evaporative fluid coolers, closed circuit cooling towers can keep your system cool and contaminant-free in a closed loop. Two separate fluid circuits are created within this model, resulting in spray water mixing with the outside air. Let’s take a look at closed circuit operation and configuration below.
Closed Circuit Cooling Tower Operation
These cooling towers operate similarly to open cooling towers. One of the only differences between the models is the heat load is transferred from the process fluid to ambient air through a heat exchange coil in closed circuit towers. The coil will isolate the process fluid from the outside air. This will keep it clean while in a closed loop.
Two separate fluid circuits are then created. They include an external circuit, which spray water circulates over the coil, eventually mixing with the outside air. The second is an internal circuit, in which process fluid circulates inside the coil. Heat is transferred from the internal circuit, processed through the coil to spray water, then to the atmosphere.
Combined Flow Configuration
Combined flow utilizes both a heat exchange coil and fill for a successful heat transfer. The fill addition will reduce evaporation in the coil section, which drastically reduces the potential for fouling and scaling. These closed circuit cooling towers use parallel flow of air and spray water over the coil, with crossflow water and air flowing through the fill.
Parallel flow means the water and air flow over the coil in the same direction. Process fluid will travel upwards to the top of the coil, which increases efficiency by bringing the coldest spray water in contact with the process fluid.
Counterflow Configuration
The flow of air goes in the opposite direction of the spray water in closed circuit towers. Air travels vertically through the unit while spray water goes downward over the coil. Process fluid then flows from top to bottom through the coil.
Induced Draft
Induced draft cooling towers are a type of mechanical draft tower that features one or more fans. These fans will be located atop the tower, drawing air upwards against the downward flow of water. The water is passed around the wooden packing or decking. In these models, the coolest water is found at the bottom, coming in contact with the driest air since the airflow is counter to the water flow.
With the warmest water found near the top of the tower in contact with moist air, this results in an incredibly efficient transfer of heat. Induced towers will either come in round or square shapes, distributing water via a sprinkler or static branch system. Incoming water is injected throughout the tower with a spray distribution header. The spray is directed downwards in order to maximize the contact of water and air. This process is maximized by the cooling water fill, which is made up of wood, metal, PVC or other materials. In general, induced draft models offer the most effective solution to the cooling needs of any industry.
Forced Draft
There are many benefits of using a forced draft cooling tower. And that is exactly why so many industrial plants opt for this model over the other options. Forced draft cooling towers are very powerful and affordable at the same time. These models will remove low-potential heat that is generated in the production process. A counterflow of air combined with hot water results in a transfer of heat in the cooling fill. Paper and chemical industry plants often prefer to used forced draft cooling towers.
Cooling Tower Installation, Replacement, & Refurbishment in Arizona & Nevada
Our team offers complete cooling tower refurbishment that will save your company tens of thousands of dollars over buying and installing new cooling towers. Cooling tower refurbishment and rebuilding adds about another 15 years of life to your equipment and helps you get your money’s worth out of your original investment in your cooling tower or property. We offer cooling tower installation, replacement, and refurbishment in Arizona and Nevada. We also sell other cooling tower parts and products.