Understanding air movement and control systems is vital for any pneumatic application. When considering your next design, there are many aspects one can easily overlook. A part of this process that is often neglected is the financial return one gains from their equipment. If your application depends on using an air compressor you may want to take a second look at what this is actually costing you. Switching to a regenerative or centrifugal blower can reduce running costs as much as 95%! When you have a job to do and a deadline to meet, it is easy to jump to the first option, but with compressed air, you’re just blowing your money away.
It’s easy to see the physical differences between these machines, but what we are concerned about is their function and efficiency. An air compressor consists of three main components: the compressing mechanism, the power source, and the storage tank. The fundamental working principle of an air compressor is to compact atmospheric air. Ambient air is drawn in through the intake valve, and compressed with a piston into a sealed metal tank. Since the quantity of atmospheric air is continuously added to the storage tank, the pressure increases until a predetermined value is met. In summary, atmospheric or free air is packed together after decreasing its volume and increasing its force.
A regenerative blower can be broken into two main components: The power source (AC motor), and the air chamber (inlet, outlet, impeller, and the impeller housing). Regenerative blowers are typically direct drive in design. The impeller spins within the housing that consists of an inlet and outlet "channel". As the impeller passes the inlet port, air is drawn in. As the impeller rotates, air is captured between each blade on the impeller and is pushed both outward and forward into the channels. The air then returns to the base of the blade and is then forced out the outlet. This process is repeated over and over as the impeller spins (hence the name “regenerative”). But how does this equate to cost savings? The answer can be determined by evaluating your application.
What’s the Difference?
It takes a lot of energy to pressurize air, but not a lot of energy to produce air flow (volume). A regenerative blower will produce air flow at a constant rate until resistance is met, as resistance increases, the air flow decreases and the pressure starts to increase, dynamically adapting to your requirement. Think of this as the blower taking what it needs to get the job done, nothing more. A compressor is a lot less efficient because of its fundamental principles of operation. The inefficiency exists because your application may not require as much pressure as the compressor is set to. For example, if you need 40PSI for your pneumatic application to function adequately, but your compressor pressurizes air up to 120PSI before turning off, a lot of energy has been wasted pressurizing air unnecessarily. This costs you money.
It is important to understand that to really see the cost savings you have to evaluate your application. For example, if you’re in a plant that uses an air knife system, whether it be for drying or blow off, a single operation in this plant using a 4’ (1.2 m) pipe with slits can use more than $350,000 in compressed air annually. A more efficient drying or blow off system can do the same job for just $30,500 – a potential savings of more than $300,000 each year. In many operations, the use of compressed air can be eliminated completely by using an air knife package powered by a regenerative blower, bringing the cost of annual operation to about $3,600. Many times customers will see a financial return on their equipment cost in 3- 6 months. It is also important to consider the material that is being moved. In applications where steam is present, heated air is partiucularly advantageous. Regenerative blowers provide an efficient source of heated air. Heated air is better absorbed compared to compressed air that tends to cause steam to condense and solidify. Regenerative blowers also offer oil-free operation unlike compressed air systems. For instance, in an application where clean air needs to be in contact with your product then a regenerative blower would be your best option as the air being supplied from the blower is 100% oil free. This is particularly helpful when air will be in contact with food, medicines, drinks and beverages, electrical components and other areas where oil can be hazardous. The same can be said for routine maintenance. The regenerative blower is so simple in its design that little maintenance is required. With its frictionless motor design and compact size, a regenerative blower can last between 15-20 years if run within proper conditions.
Making the Switch
A lot can be said about regenerative blowers and their ability to move air more efficiently. If you are considering making a switch from compressed air to a regenerative blower system, please contact Atlantic Blowers. Our team has helped hundreds of companies save money and make their air systems as efficient as possible. We specialize in analyzing applications and designing systems that insure reliability and longevity.