Industrial Utility Efficiency    

System Assessment

Great Plains has carved a global reputation for producing world-class seeding equipment since it first opened its doors in 1976. Great Plains manufactures a range of products from grain drills and planters, to compact drills and tillage equipment. They have established an international business built on expertise, knowledge and a commitment to producing products meeting the rigorous demands of the agricultural sector.

Compressor Controls

A large mining complex in a remote northern region of the world invited a compressed air auditor in to assess the efficiency of a problematic system. Site personnel and their air compressor supplier were concerned a system in one of the buildings was not running optimally, and wanted to know what size of compressor to install in the facility. The auditor found significant savings in this target system, but even larger potential savings were found in other ancillary systems in the complex, as part of an extra investigation conducted while at the site. Overall, the potential energy savings total more than half of a million dollars, if all recommendations are implemented.

Piping Storage

Their job is to brake the cars by gripping the wheels. They are operated either pneumatically or hydraulically, with Alton & Southern Railway’s system using the former. Considering much of Alton & Southern Railway’s compressed air piping system dated back to its 1960’s installation date, there were leaks. As of 2012, it was determined one and a half compressors were running at 100% capacity just to maintain leaks. This equated to about 1,500 cfm at a cost of roughly $180,000 in electricity annually.

End Uses

A meat processor, located in Canada, hired a consultant to assess their compressed air system as part of a company-wide energy conservation effort. The assessment and analysis showed, despite having a modern compressed air system using a VSD air compressor and pressure/flow control, the system was running inefficiently and had significant levels of leakage and inappropriate use.

Pressure

A Canadian chemical plant installed a large heated blower-purge style compressed air dryer, years ago, to condition the instrument air system against freezing temperatures.  The dryer selected was oversized for the connected air compressors and had unused on-board energy savings features.  A compressed air assessment revealed the site air compressors and compressed air dryers were running inefficiently and causing in-plant pressure problems.  Repairs to a compressed air dryer and the replacement of aging air compressors and dryers has reduced compressed air energy costs by 31 percent.

Air Treatment/N2

This plant has three production lines producing snack food. Depending on the time of year and production demand the plant can operate anywhere from no production lines to all three production lines. A thorough supply and demand-side system assessment was done at this plant. This article will focus on some recommended demand-side reduction projects including nitrogen generation, air vibrators, leaks and vacuum venturis.

Leaks

Petro Chemical Energy, Inc. (PCE) specializes in energy loss surveys for the refining and chemical industries. We’ve been providing Compressed Air Leak Surveys, Nitrogen Leak Surveys, Steam Leak Surveys and Steam Trap Surveys – for over twentyfive (25) years. We operate totally independent of all equipment manufacturers to ensure our clients receive a complete and unbiased report of the leaks in their facility. PCE has conducted compressed air leak surveys for hundreds of customers at thousands of sites. Undetected, compressed air and gas leaks rob efficiency in manufacturing and processing industries. As a result, businesses lose millions of dollars annually in energy costs and lost production time.

Pneumatics

Energy, in all forms, has always been a key Lantech focus. It was, in fact, a key element of the core packaging problem the company’s founders set out to address. They saw an opportunity to capitalize on an inexpensive and under-used resource – stretch film – to displace a high materials cost and energy intensive way of unitizing pallet loads of products – shrink bagging.

Vacuum Blowers

Every municipality and utility is facing the reality of rising energy costs. In 2010, the Town of Billerica, MA, which is located 22 miles northwest of Boston with a population of just under 40,000 residents, engaged Process Energy Services and Woodard & Curran to conduct an energy evaluation of the Town’s Wastewater Treatment Facility (WWTF) and pump station systems sponsored by National Grid. The objective of the evaluation was to provide an overview of each facility system to determine how electrical energy and natural gas were being used at the facility and to identify and develop potential costsaving projects.
When a company is considering making an investment of more than a million dollars in system upgrades, it is crucial for them to review all options to get the best return. By exploring energy efficiency impacts throughout the entire compressed air system, vendors can propose projects resulting in both a larger sale for them and increased financial benefits for their customers, while still meeting capital expenditure guidelines. This “best of both worlds” scenario was evident when a foundry in the Midwest was evaluating options for replacing its steam system used to drive the plant’s forging hammers.
EnSave, an energy auditing company based in Richmond, Vermont, recently performed compressed air audits at two facilities of a leading U.S. steel manufacturer. Both plants are mills that melt, cast, and roll steel to produce a variety of products, including: rebar, merchant bar, steel flats, rounds, fence posts, channel bar, steel channels, steel angles, structural angles and structural channels. These products are used in a diverse group of markets, including: construction, energy, transportation and agriculture. Compressed air is provided at 100 psig in both plants for a variety of applications — from optical sensor cooling to pneumatic cylinders for stacking finished products.
Compressed air has moved to higher visibility in the energy conservation field, and the buzzwords abound: “the fourth utility” — “your most expensive utility” — “eight times more expensive than electricity” — “a quarter-inch leak costs $9,000 in wasted energy.” This greater awareness has also produced compressed air auditors that are springing up like summer dandelions. With audits available from many sources, it is important to understand what plant operations, engineers and maintenance managers should expect from a complete audit — or more aptly — a complete air system review.
As a reader of this journal, you are well aware that large compressed air systems often have significant wasted air — often from leaks — that represent tens of thousands of dollars of waste per year. However, it is our experience that the so-called “low-cost” measures identified often go un-repaired, while other more costly capital projects get funded. Why? With an ROI of a half year or less, they seem like IQ tests to many compressed air auditors.
Many thousands of dollars of annual electrical savings are being achieved worldwide using special purge reduction controls on desiccant air dryers. These controls reduce the expensive purge air that must flow through the dryer to regenerate the desiccant beds. But, unexpected problems with these controls can cause hidden problems that can reduce or eliminate the savings.
After more than 25 years in the compressed air industry, it still amazes me that many plant personnel and even those who sell compressed air products for a living don’t fully understand the relationship between flow, or volume (cfm), and pressure (psig). Walk into many body shops or small manufacturing plants, and you will find the compressor operating at an elevated pressure to satisfy the “demand.” If a plant has low air pressure on the production floor, what is the first thing that the maintenance professional does? You guessed it: He or she “jacks” up the pressure on the compressor, not realizing that he or she made the problem worse.
Compressed Air Performance Specialists (CAPS Inc.) is a compressed air consultancy located in Calgary, Alberta. In its most recent compressed air project, the company reduced a 200-hp, multi-compressor system down to a single, 100-hp variable speed drive (VSD) air compressor utilizing 75 hp of compressor energy (kWh), resulting in $70,000 in annual energy savings.
There is a partly true idea floating around some plant maintenance circles that “compressed air is free.” Readers of this journal know that isn’t true. But, what if non-compressed air could be seen as “free?” Is there something we can get for free from nature to reduce the cost of our compressed air? What if lower temperature intake air was nature’s gift? What if all we need is a bit of tin to duct air from a different source?
Replacing air compressors, dryers and filters with more efficient models has saved electrical costs and improved compressed air reliability at the Canada Bread plant in Winnipeg, Manitoba. In addition to this, plant personnel found some additional savings by reducing air leakage and eliminating inappropriate uses. As a result, the plant reduced its compressed air electrical costs by 58 percent and qualified for a utility incentive.
A major snack food manufacturer spends an estimated $148,220 annually on energy to operate the compressed air system at its food processing plant located in the Mid-Atlantic area.  As electric rates rise from their current average of 8 cents per kWh, their annual expenditure will only increase.