By: Alyssa L. Ochs
Compressed air systems are often misunderstood in the brewing industry and undervalued as a long-term investment; however, compressed air is an essential part of the brewing process, and an efficient system is integral. Choosing the best pneumatic system for brewery operations requires understanding the uses of compressed air in a brewery, the types of compressors available, and the size, focus and other needs of the brewery.
Brewery Uses for Compressed Air
Although every brewery operates differently, there are a few common uses for air compressors that are very important to the brewing process. Compressed air is used as a means to get yeast cultures enough oxygen during fermentation. Brewers also use compressors to aerate wort and water, and to transport solids, such as spent grains, whole malt, and sugar.
During bottling, compressed air can move beer from the conditioning tank to the bottle, as well as keep lines clean and free of water. It is used during canning and clarifying to remove solids and create a cleaner product, and controls valves and actuators in automated packaging and labeling processes. Some maintenance and sanitation also require compressed air, powering air tools and pressure washers.
Types of Air Compressors for Breweries
There are two primary types of air compressors used by modern breweries. The first is the pressure-lubricated reciprocating or piston air compressor. These compressors use a piston and cylinder driven by a crankshaft to compress air and feature either a single-stage or double-stage operation. Single-stage piston air compressors bring air in with a single-piston stroke that’s about 120 PSI.
Meanwhile, double-stage compressors compress air up to about 175 PSI with an additional compression step through a second piston. These compressors are often used for low-pressure tasks, such as washing kegs.
The second type of brewery air compressor is a lubricated rotary screw compressor. The rotary screws in these compressors utilize a positive displacement system and a hydraulic seal to transfer energy between rotors. The screw design and rotation forces air to move through the compressor. These types of compressors are better suited for high-pressure tanks and are useful for bottling and other brewery tasks.
When shopping for compressors, brewers can choose between oil-lubricated compressors and oil-free air compressors, depending on their needs. Lubricated compressors are typically equipped with filtering systems to ensure that contaminants stay out of beer.
As an alternative to the piston compressor for brewery applications, some brewers use oil-free scroll air compressors for continuous clean air and quiet operation. These machines can be installed anywhere due to the low noise levels and no pressure drop-offs.
Brewery Size Matters
Michael Camber, Marketing Services Manager for Kaeser Compressors, Inc., told Beverage Master Magazine that the full range of craft breweries’ production levels would affect their pneumatic equipment needs.
“Larger brewers tend to have a broader variety of pneumatic devices, as well as more of them,” Camber said. “Our craft brewers typically purchase rotary screw compressors from 5-50 hp, though most craft brewers are in the 5-25 hp range. These are most often bought as part of a system that includes tanks, drains, dryers, and filters. These are vital to cleaning up the air to protect brewers’ expensive equipment. Many choose AIRTOWERs and AIRCENTERs, which are complete compressed air stations with storage tanks and air treatment components built into a space and time-saving package.”
In addition to the high-quality air they provide, Camber said that these compressors are extremely reliable and energy-efficient.
“These machines are designed for demanding manufacturing and processing applications and can run 24/7 if needed,” he said. “A bonus is that the packages are quiet, which is especially important if people will be working near the compressor or the brewery has a public taproom on-premises.”
Compressors Used by Breweries
Due to their varying needs, no two breweries use their air compression systems the same. The market also provides brewers with plenty of manufacturers so that they can find their perfect pneumatic fit.
Offering year-round, seasonal, and unique one-off beers, D9 Brewing Company has been on the local craft beer scene in Cornelius, North Carolina since 2014. Andrew Durstewitz, CEO and founder of D9 Brewing, told Beverage Master Magazine, “We use an Ingersoll Rand compressor for all pneumatic controls in the brewhouse, packaging, and aeration of wort.” (Photo on Right)
Peter Licht, brewmaster for Hermitage Brewing Company in San Jose, California, said he uses rotary screw compressors with integrated dryer for all of his brewery’s compressed air needs. Hermitage Brewing Company is a big part of the growing craft beer scene in San Jose and offers a pubic tasting room, growler fills, keg orders, and brewery tours.
Meanwhile, Drew Yeager, Director of Brewery Operations for Fat Bottom Brewing in Nashville, Tennessee said his brewery uses an Atlas Copco SF22+ FF Oil-free air compressor.
“This is used to provide oil-free, dry air to our production equipment including the chain-vey conveyor system, centrifuge, keg washer, canning line, PakTech applicator, CIP system, and central foaming system for floor cleaning,” Yeager said.
Established in 2012 as East Nashville’s first brewery, Fat Bottom Brewing brews a wide variety of beers inspired by styles all around the world.
Brewery Compressor Considerations
For brewers in the market for an air compressor, many questions should be raised internally and with manufacturers. One important consideration is to understand the size of air compressor the brewery needs to not burn out and put operations at a stand-still. Brewers should also take into account where to physically place the compressor in the brewery to reduce noise and potential damage to brewing equipment.
Some brewers have made the switch from oil-based air compressors to oil-free versions. Oil-free air tends to be better for brewing because oil can kill yeast, flatten a frothy head, present safety hazards, and reduce purity.
Camber of Kaeser Compressors defined and described what he considers the six most important factors a brewery should consider when purchasing an air compression system.
1. Reliability – If the operation has mission-critical equipment with pneumatics, you want something well-built so you don’t have downtime.
2. Energy efficiency – Depending on local utility rates, size of machine (hp), and the running hours, energy can be a significant cost. Efficiency varies widely between compressors.
3. Operating temperature – This impacts how easy or hard it will be to remove moisture from the compressed air. The lower the operating temperature, the easier it will be to prevent moisture from affecting equipment and product.
4. High oil carryover – the carryover rate also impacts air quality and can be a real problem with some compressors. The lower it is, the better for both product quality and equipment reliability.
5. Low vibration – over time, vibration will loosen internal piping and electrical connections, causing downtime. Look for compressors that run smoothly and have good vibration isolators.
6. Noise – if people will be working near the compressor, low noise is important for morale, health, and safety.
Durstewitz of D9 Brewing said the most important considerations for his brewery concerning air compressors are reliability and sanitation. Licht of Heritage Brewing said air quality, reliability, and sound are the top things they keep in mind when looking at air compressors.
At Fat Bottom Brewing, Yeager said oil-free and dry air are the most important considerations for his brewery’s air compressor decisions. Other factors he said are “planning for SCF required day one and with a growth plan for sizing,” as well as the “noise level for employee comfort and OSHA compliance.”
Choosing the Right Brewery Air Compressor
There is no one-size-fits-all solution for brewery air compressors because every brewery’s compressed air needs are unique. To get started, talk to experts at air compressor companies that serve breweries as a primary market, as well as other craft brewers about what systems work well for them.
Durstewitz of D9 Brewing recommends not winging it when choosing the size of your air compressor. “Make sure to accurately calculate your CFMs and pressure requirements. If you run a compressor too hard it’ll just burn out,” he said.
Heritage Brewing Company’s Licht said breweries should “plan for future air needs, make sure the air quality is appropriate for the use, and do not install a noisy compressor in work areas.”
Fat Bottom Brewery’s Yeager stands behind oil-free. “Bite the bullet and purchase the right oil-free, dry air compressor. You will save the difference in money with less maintenance on brewery equipment and less downtime in production.”
Finally, Camber of Kaeser Compressors warns about going too big. “Determine what size and type you need based on actual air demand, duty cycle, and how mission-critical air is to your brewery,” he said. “You want a reliable supply at a stable pressure, but you don’t want to oversize compressors. Oversizing increases your purchase costs, your energy costs, and your maintenance costs.”