Earlier this week we discussed the three different types of dryers: refrigerant, desiccant and heat of compression. So, which technology is right for your operations?
To find out, consider this simple formula: ACE, which stands for Applications, Customers and Environments.
Applications – What dew point do you need to achieve? Do you have very low temperatures in the winter and very high temperatures in the summer? A key thing to remember is that refrigerant dryers are not compatible with freezing temperatures. Also, if the equipment is located outside or if the compressed air piping is exposed to outside air, the dryer must be able to cope with a negative dew point. In these scenarios desiccant dryers will be required.
Customer – What quality of air is demanded for your application and your end products? For general applications where only protection against corrosion is needed, a refrigerant dryer is enough. However, an HOC dryer – even if it requires a higher initial investment – can pay for itself through lower operating costs and provide similar or better dew points. Applications with more stringent requirements, such as when compressed air is in contact with food, will require a dew point of at least -40°F/-40°C to remove sufficient moisture content. Guaranteed dew point HOC or desiccant dryers, sized to take into account the maximum operating conditions, will then be the right choice. Even more demanding applications, like electronics manufacturing, may require -100°F/-70°C special versions with molecular sieve of HOC or desiccant dryers.
Environment – Does the compressed air system run 24/7? What size compressors are running? Can higher investment costs easily be recovered through smaller energy bills?
Blower purge desiccant, zero purge, and HOC dryers employ more sophisticated designs and, not surprisingly, are more expensive to purchase. However, these technologies may benefit you in the long term because energy savings can pay back the extra initial investment. Additionally, reducing or eliminating purge loss brings higher outlet flow, so in most cases a smaller combination of compressor and dryer can be used. And, that can save you even more.
Drying compressed air is a relatively simple science, until you factor in variants such as energy usage and quality control. After that, the decision can become a more complex puzzle that requires thoughtful analysis. Often, all three of the technologies would do the “simple job” that you need a dryer to perform, but does the purchase “cost” outweigh the “value” that a dryer should add to your energy bill and also help improve your production quality?
If you have questions, Atlas Copco’s compressed air experts are trained to find the right solution for you and will provide a payback analysis to which we are committed and indeed proud to stand behind. Send me a note through the Ask Paul page on this site, and I will be happy to put you in touch with a professional that can answer any questions you may have.
Do you have anything to add about the dryer selection process? Leave us a comment to continue the conversation.
