Air Cooled Heat Exchangers
Filtration systems can reduce maintenance and downtime.
To attack an interesting analogy, the cooling tower and your heat exchanger is what the lungs and heart are for the human body; When good doesn’t work properly, it affects other parts of your body and your health suffers. Likewise, when your cooling tower and heat exchanger are not clean, the heat exchange process does not work efficiently and the health of the production products and the cooling process of your process.
The cooling system process relies on the cooling tower until it disappears. The heat of the cooling water process reaches this by pulling the volume of large air to the cooling tower when the water moves through the filling material back to the basin. Through a natural evaporative process, heat dissipates from water before reaching the water basin from where it circulates back through the chiller then through a heat exchanger and back again (like when you sweat and let the air evaporate and let the air evaporate to cool you). It is important to realize that the cooling tower is a giant air cooled heat exchanger scrubber who captures all floating air debris nearby, and if your system does not have effective filtration, debris can clog along and circulate and get stuck in a heat exchanger. Where it can accumulate, limit the flow of water and cause your process equipment not to work because of overheating.
Examples are illustrated by the main automotive assembly facilities that face periodic downtime because their robotic welding system does not hold tolerance and cause quality problems. After the robot technician spent a few days trying to initially solve the problem, one of the maintenance workers opened a heat exchanger and found that it was influenced by cotton seeds, insects, and other debris flows had diminished and the robot equipment ran hot. Now you might ask yourself, why don’t they have a kind of filtration equipment? The answer is simple; When the facility was built, the surrounding conditions in the area did not require a filtration system. However, as the years passed and the area became a more advanced tree population and Cottonwood grew up, the need finally appeared.
The interesting thing to note about this situation is that even though cleaning a heat exchanger gets a robot welding system back online and runs on the peak performance, it doesn’t solve the problem. In fact, cleaning a heat exchanger is like taking a cold capsule to get rid of cold symptoms. Unless you treat the root cause of the problem, the cooling system will suffer time and again. The root cause in this case and in most of the heat exchanger sacrifice situation is a cooling tower – stop the debris from entering the cooling tower and it will protect the entire cooling system process including filling, cooling water, chiller and heat. With proper filtration technology, your process cooling system will remain clean and run efficiently throughout the season.
Choose the right filtration system
It is important to realize that optimizing the ecology and operational efficiency of your evaporative cooling system is best achieved by combining a chemical treatment regimen with several types of filtration. The reason is that chemical treatment specifically targets suspended solids and 40 microns and below, while filtration systems are designed to stop larger debris, especially the types that cause system blockages and fouling.
For filtration of cooling towers, there are two general technologies: water-based systems that have several variations and air intake filtration systems. With water-based systems, the choices include basic water filters that remove debris by just passing through water through a mesh filter; The sand filtration system that removes debris by passing water through sand and centrifugal separators that rotate water and eliminate debris through centrifugal acts. Instead, the air intake filter system removes debris by filtering the air because it is being drawn to the cooling tower, keeping the debris out of the system. When considering your filtration option, the following questions must be asked.
What is the cost associated with downtime due to heat exchanger or fouling cooling tower or clogging? (Knowing this will help you justify the cost of your filtration system)
- What kind of debris is the most problematic (can you see it or it’s microscopic)?
- Specifically, which part of the system protects the filter?
- Which system provides the largest filtration surface area (this can directly impact the frequency of cleaning – the smaller the filter more often needs to be cleaned)
- Can the system be installed without turning off the cooling tower? (If the cooling tower must be turned off for installation, you need to enter the lost productivity into the cost of your filtration system if it is not installed during the shutdown period.)
- How much does it cost related to the filter and installation?
- How easy is the system to install and maintain?
Answering the above questions will help you fully understand your options and to make the best choice for your operation.
In terms of automotive manufacturers, the solution they choose is the air intake filter system. The reason is that they need a system that will protect the entire cooling system process including filling materials, cooling water, chiller and heat exchangers. When they evaluate water-based systems, they find that options provide various levels of protection for chiller and hot exchangers but do not protect the cooling tower where the root of their problems. If they have chosen a water-based system, their cooling tower will still draw air debris into stuffing and water where the water filter will catch debris before circulating throughout the system. From a maintenance point of view, which will solve the problem of heat exchanger but will not do a little to reduce maintenance on the cooling tower. Furthermore, when they compare water-based filtration costs versus air intake philtration technology, air intake filtration is found as a more cost-effective approach for their operations.