Air-Cooled Vs. Water-Cooled Compressor
For big industrial plants, one of the biggest considerations they have to make when choosing a rotary screw compressor is whether they should go with a water-cooled or an air-cooled unit. Well, both of these versions have their own advantages and disadvantages.
Generally, majority of the rotary screw compressors installed are air-cooled. They are, after all, readily available, and they also cost a lot less when it comes to installation. However, you should not overlook the fact that there are applications when choosing water-cooled compressors would be better. So how do you choose? The best way to reach a sound decision is to consider the installation of your compressed air system.
Here are some considerations you want to make when choosing between air-cooled and water-cooled compressors:
The Energy Costs of Air-Cooled versus Water-Cooled
A water-cooled unit would have a lower specific power compared to an air-cooled compressor which basically means you can expect it to be more efficient. But you would also like to consider the electrical costs of the cooling system as well as the water and water treatment costs. Once you factor in those expenses, you might find that an air-cooled compressor is actually more cost-effective.
Still on the other hand, you can also think about the heat recovery potential when you use the cooling water to preheat plant processes. This could offset the expenses of that cooling water, again a plus point in favor of water-cooled compressors. There are also space-heating opportunities with air-cooled compressors, too but it is usually available just seasonally.
The Layout of the Compressor Room
Is there enough room for the compressor you have in mind? Pretty simple question, isn’t it? There’s actually more to it. If the demand of your plant is not that constant, you might want to consider multiple small horsepower compressors that you can coordinate, instead of a single large one. Know however, that small horsepower rotary screw compressors are not usually available in water-cooled varieties. Check the layout of your compressor room and try to visualize mentally how the compressor will fit in the room and where inlet air as well as discharge ducting would go.
The Ventilation in the Room
Air-cooled compressors require sufficient amounts of cooling air for the inlet, as well as sufficient space for discharge. Temperature regulation issues, equipment failure, and ultimately plant downtime, are often caused by improper or inadequate ventilation.
If your compressor room is near a boiler room or an area where fumes can possibly be ingested into the inlet, know that it’s not the best place for air-cooled compressors. If what you have is a confined space, water-cooled compressor is a better choice.
After you have made these considerations, make sure you study the numbers. Only by doing so will you see which one suits your application better.