Industrial Utility Efficiency

Food Processor Conserves Energy with Compressed Air System Audits


There is no such thing as an invisible compressed air system that can efficiently deliver air without fail. But it’s nice to think of it that way if one can, especially if the system helps save energy and reduce cost.

So says the director of engineering at a food processing company located in Canada. 

“A compressed air system is something you want to be invisible because that means you never have a problem with it,” said the director of engineering. “But the day you have to think about it that means something didn’t work out.”

Out of mind is exactly the status of the compressed air systems at the firm today, thanks to major overhauls at its two large production operations. For all intents and purposes, the company’s upgraded compressed air systems are now cloaked in reliability – all the while helping the company keep pace with growth and conserving energy in the bargain.

 

Sustainability a Driving Force

Sustainability is a driving force for this food processor.. The company could not be more dedicated to sustainability, said the director of engineering. “It’s out duty to society to provide people with sustainable solutions that reduces their environmental impact, while still being able to enjoy products they like to consume,” he said. “Then the other end of it is how can we produce product more sustainably? Reducing our energy is, of course, a big one.”

Components of the updated compressed air system at the food processing plant are housed in a BOGE in a BOX container outside the facility.

 
Growth Sparks Compressed Air Audit at Facility #1

A focus on sustainable products and packaging, in combination with a passion for quality, has resulted in considerable growth for the firm. Plans to add production lines at facility #1, in turn, drove the need to address the plant’s faltering compressed air system.

The original compressed air system consisted of two fixed-speed, rotary screw, air compressors in addition to a refrigerated dryer and a receiver tank. The system was incapable of meeting increased demand for air. Additionally, spikes in demand resulted in pressure drops at production machines. The air compressor airends also began failing and needed to be replaced.

The food processor brought in CRU AIR + GAS - headquartered in Mississauga, Ontario, Canada - to recommend the best solution to address immediate and future needs. A detailed compressed air audit conducted by CRU AIR + GAS showed the existing system was unable to efficiently supply compressed air to meet the load profile due in large part to minimal supply side storage, as well as two-inch piping and a two-inch header octopus configuration that combined to restrict airflow. The audit also pointed to considerable air leaks and the potential for substantial energy savings.

The compressed air audit led to the installation of an energy-saving rotary screw VSD air compressor. 

 

Supply- and Demand-side Issues Tackled

Based on CRU AIR + GAS’ recommendation, the food processor opted to replace the existing air compressors at plant #1 with an oil-flooded, variable speed drive (VSD) air compressor. The system also included a variable capacity refrigerated dryer, along with an oil mist eliminator and zero loss drains. Due to space limitation in the plant, the air compressors and air treatment components are housed in a steel and insulated container located outside the facility. Air is routed into the facility situated approximately 10 feet from the containerized system.

A highlight of the installation included two new receiver tanks and four-inch header piping in place of the two-inch piping on both the supply and demand side of the system. 

“They had a deadhead at the plant where the air just ended,” said CRU AIR + GAS President Shannon de Souza. “So, we installed one of the large receiver tanks in the middle of the plant and connected it to both ends to create a ring main.”

A holistic compressed air audit led the food processor to overhaul the compressed air systems at its operations, including the one shown at facility #2.

 

Increased Production Planned at Facility #2

At facility #2, planned production increases prompted the food processor to retrofit the compressed air system to meet more demand for air. As with facility #1, increased reliability and overall system efficiency was essential to the investment. The company subsequently hired CRU AIR + GAS for the project based in part on the success at facility #1.  

The original air compressors included three larger fixed-speed, rotary screw, air compressors and one small air compressor. It also included two refrigerated dryers. As with facility #1, an air audit demonstrated the inability of the existing system to efficiently supply air to meet the facility’s load profile given inadequate air storage, as well as two-inch piping and a partial ring main that together caused significant pressure drop at some production machines. 

“The plant had a huge pressure drop of 12 psig to the air treatment components because air was being choked at the supply side of the system,” de Souza said, noting the refrigerated dryers also operated in parallel, creating inefficiencies. Additionally, an idle load test of the air compressors revealed an average daily loss of air of 43% due to air leaks, demonstrating more potential energy savings.

CRU AIR + GAS’ team of trained and highly skilled technicians supports customer operations around the clock.

CRU AIR + GAS

Headquartered in Mississauga, Ontario, Canada, with an office in Carrollton, Georgia, CRU AIR + GAS focuses on a holistic approach to serving manufacturers in virtually every industry sector. 

The company’s diverse product portfolio includes oil-flooded and oil-free rotary screw air compressors, centrifugal air compressors, oil-free reciprocating air compressors, single stage and two stage PET Blow Molders and a robust offering of auxiliary compressed air system technologies and components. Its product line also boasts onsite nitrogen generators, as well as a portfolio of chillers. 

CRU AIR + GAS’ in-house team of trained and highly skilled technicians is equipped to support customer operations around the clock. The company is also well suited to helping companies strengthen their sustainability initiatives with its in-house auditing team consisting of two professional engineers, a certified energy manager, and a certified energy auditor.

For more information, visit www.cruairgas.com.

 

Solution Mimics First Project 

Following the audit and internal planning for future needs, the firm decided to overhaul the compressed air system at facility #2 based on CRU AIR + GAS’ recommendation. The solution, in some ways, mimicked the project at facility #1. 

The project included the replacement of the original air compressors with a new VSD rotary screw air compressor as well as a fixed-speed, direct drive, rotary screw air compressor. CRU AIR + GAS also installed a wet receiver tank and a heatless regenerative desiccant dryer providing a pressure dewpoint of -40oF (-40oC), along with a purge economizer. 

The system is equipped with an oil mist eliminator to treat air before the dryer and a second one to treat it after the dryer. The installation also included the addition of a dry storage tank and low pressure-drop filters, as well as zero loss drains on all receiver tanks. As with facility #1, CRU AIR + GAS replaced the two-inch piping header with a four-inch header. A final component of the upgraded system was the addition of a master controller to monitor and manage the compressed air system.

The food processor also contracted with CRU AIR + GAS to repair and manage compressed air leaks at both production facilities.

 

Positioned for Ongoing Success

The end result at both plants is the efficient and reliable delivery of compressed air today and well into the future. The projects also achieved energy and cost savings. At facility #1, the system saves the company 580,654 kilowatt hours (kWh) per year for a total of \$79,171 per year in cost savings. Facility #2 saves 445,707 kWh per year, shaving \$66,856 off its annual electric bill. Thanks to the Canadian Save on Energy program, the payback on the investment for facility #1 is 1.9 years, while the payback for facility #2 is 2.5 years. 

For the director of engineering, there is no longer any need to ponder the effectiveness and reliability of their compressed air systems. The focus, instead, is on continuing to deliver high-quality, sustainable products to the marketplace for many years to come.

“Our energy consumption has been reduced and the systems are invisible as they should be,” he said. “It puts us in a position where we can increase production without having to worry. And our overall goal is to be more sustainable. We’ve done that on our materials side and now we’re making even more progress on the energy side.”

 

All photos courtesy of CRU AIR + GAS.

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