Cooling tower systems are commonly used on industrial, commercial, residential, and healthcare buildings throughout the country. There are approximately 2 million cooling towers operating today in the US. As these cooling towers are responsible for maximizing evaporation from hot water sources, the efficiency rating of the system is of extreme importance.
But what does a high-efficiency cooling tower system look like? Well, this can be based on a wide range of factors that often relate to the overall design of the cooling tower. This includes things like:
- Wet-bulb temperature
- Cooling range
- Water circulation rate
- Air velocity
- Tower height
Overall, the efficiency of a cooling tower system comes down to the makeup water quality and cycles of concentration (COC). Essentially, a high-efficiency cooling tower system will require fewer cycles for the cooling process before the water is discharged.
Improving the efficiency of a cooling tower can offer countless benefits, such as lower cost of operations, reduced water waste, and lower energy consumption. So how can you significantly improve this factor in your current cooling tower system?
Here are 5 simple ways to increase your tower’s efficiency rating.
1. Determine the Type of Cooling Tower You Have
The first step to improving your cooling tower’s efficiency is determining which type of cooling tower system you have. The design of a cooling tower often depends on the workload and intended use of the system. Overall, there are three main categorical types of cooling tower systems whose names describe their approach to the water-cooling process.
Once-Through Cooling Towers
As the name implies, a Once-Through Cooling Tower runs in a single cycle, absorbing as much heat as possible before the water is released back to the initial source. These are typically used when the original source is a body of water such as a lake or river. They are also not ideal for high-volume applications, as the average temperature change is between 5 to 10° F.
Open Recirculating Cooling Towers
An Open Recirculating Cooling Tower system is the most common type amongst industrial buildings. This recirculates the same water until the desired temperature is reached. But this uses an open system, which allows even more heat to evaporate into the environment, which helps to improve the efficiency of the tower.
An open recirculating cooling tower uses 3 pieces of equipment: recirculating water pump(s), a heat exchanger, and the cooling tower itself. The cooling tower is built on the exterior of the building, which allows for air to come in direct contact with the water.
Closed Recirculating Cooling Towers
In a Closed Recirculating Cooling Tower system, the water is never exposed to the air, which helps to eliminate water loss. As the water is recirculated through the system, heat is absorbed into the cooling tower and transferred to a second coolant. Cool air runs over the tubes that the water is circulating through, helping to reduce the water temperature.
2. Use the Correct Water Treatment
Once you determine the type of cooling tower system in your building, your next step to improving efficiency is using the right water treatment. Since cooling towers have a high level of heat and moisture, bacteria can start to form in the system quite easily. One of the most common types of bacteria found is Legionella, which can lead to dangerous outbreaks if it is not treated.
Removing bacteria, minerals, and other debris from the water is critical for ensuring your cooling tower’s efficiency. These deposits can build up and form “sludge” in the cooling tower, making it more difficult for the system to run properly.
The type of treatment will depend on the levels of impurity in the water. For instance, select filtration devices or chemicals are needed to remove toxins from the water, while other types may just require chlorine treatment.
3. Inspect and Clean Your Cooling Tower Regularly
Inspecting and cleaning your cooling tower system regularly is one of the best ways to keep it running efficiently. Preventative maintenance ensures that the entire system is running properly, and any mechanical parts are repaired or replaced before they cause any major issues.
Your inspections should also include checking on the individual components of your cooling tower, including:
- Looking for signs of corrosion on all mounting bolts
- Inspecting the internal parts of the motor
- Lubricating any applicable mechanisms
- Checking for signs of wear on the basin flow control valves
- Monitoring the blowdown system operation
- Checking on belt alignment
- Inspecting the fan blades’ pitch, clearance, and vibration
By taking the time to clean any build-up and debris and replacing worn-down parts, you can significantly improve the efficiency of your cooling tower. This will also help you to avoid sudden unplanned repairs due to mechanical breakdowns.
4. Track Your Cooling Systems Water Losses
Water loss is one way to monitor the efficiency of your cooling tower system. While it is virtually impossible to have no water loss during the process, the ideal range is a 1% loss of water mass per every 10°F temperature drop.
You should be monitoring and recording the amount of water that escapes from your cooling tower and noting any changes. If the water loss is increasing suddenly, it is likely a sign of a leak or drift loss. Gradual changes are commonly caused by mechanical decline, so some maintenance may be needed.
5. Improve Your Chemical Usage
If you are using chemical treatments for your cooling tower system, be aware of the effect it can have on its efficiency. Some types of chemicals are designed to support system efficiency by reducing corrosion and enhancing system longevity.
For instance, pH adjusters can help to keep these levels within an ideal range, lowering the risk of corrosion within the tower. Scale inhibitors also help to reduce build-up, meaning you won’t have to shut down your tower for thorough cleanings as often.
Finding the right chemical concoction for your cooling tower system is difficult and should be handled by a professional. This may involve using fewer chemicals, using the right ones for your cooling tower type, or optimizing your chemical dosing system. It’s best to consult with a cooling tower expert to determine the best way to optimize your chemical usage.
Over to You
Supporting the efficiency of your cooling tower system may require some little tweaks here and there until you find the right balance. Enforcing a routine inspection and cleaning schedule, adjusting your chemical usage, and monitoring water loss can make a significant difference.
However, if you notice that your cooling tower’s efficiency has dropped significantly, you may require professional services. Pinnacle Cooling Tower Service offers maintenance, repairs, and cleaning throughout the New Jersey and the greater New York City area.
Contact us
To learn more or to schedule a service with us, please contact us online. We can set up a free initial inspection along with an accurate estimate to help you improve your cooling tower system’s efficiency.
