Technology

Sometime in mid-2015, I received a call from a project engineer at a major plastics firm. He had a troubling issue with one of his PET bottle plants. The bottom line was this: They could not run all five high production blow-molding machines at one time—even though they were able to do so 18 months previously.

Any modern food manufacturing facility employs compressed air extensively in the plant. As common as it is, the potential hazards associated with this powerful utility are not obvious and apparent. Food hygiene legislation to protect the consumer places the duty of care on the food manufacturer. For this reason, many companies often devise their own internal air quality standards based upon what they think or have been told are “best practices.” This is no wonder, as the published collections of Good Manufacturing Practices (GMPs) that relate to compressed air are nebulous and difficult to wade through.

Compressed Air Best Practices® Magazine and the Compressed Air and Gas Institute have been cooperating on educating readers on the design, features, and benefits of centrifugal compressor systems. As part of this series, Compressed Air Best Practices® (CABP) Magazine recently caught up with the Compressed Air and Gas Institute (CAGI). During our discussion, we reviewed some of the things readers should consider when installing a centrifugal compressor system.

Air-operated double diaphragm (AODD) pumps are common to many manufacturing facilities. As estimated by veteran compressed air auditor Hank van Ormer of Air Power USA, approximately 85 to 90 percent of plants in the United States have AODD pumps. They are used for all kinds of liquid transfer applications, like those found in chemical manufacturing, wastewater removal, and pumping viscous food products.

One of the statements made in the Compressed Air Challenge’s Fundamentals of Compressed Air Systems seminar is that improvements can always be made to every compressed air system, including new ones. The statement definitely applies to a Canadian pork processing facility built a few years ago. This article is based on a compressed air audit performed two years into the life of a brand new plant. The audit found numerous problems and made recommendations that helped reduce plant compressed air operating costs by 60 percent. 

There is always something new to learn about compressed air systems – particularly in regards to compressed air dryer installations. As I discussed in Part 1 of this series, you can make compressed air dryer installations more reliable by understanding the consequences of any modifications you make to the system.  As a continuation of those ideas, Part II explores more ways to make a dryer installation more reliable. Discussions include: the difference between operating a desiccant dryer in a fixed cycle opposed to demand mode, what happens when you operate a heated desiccant dryer with the cooling air turned off, and how to deal with the unintended consequences of dedicating a desiccant dryer to a compressor. 

A modern dairy without compressed air is nowadays no longer imaginable, and it is used primarily for driving control units and machinery. Approximately 60 percent of the compressed air generated is used for packaging lines. However, compressed air is one of the most expensive energy sources in dairies. Even in carefully maintained compressed air systems, about 20 percent of the generated energy is lost through leaks. In particular, vacuum leakages in separators result in high energy losses. A small leak can cost up to several thousands of Euros a year.

Critical applications — such as semiconductor manufacturing, food processing and automobile spray finishing — require high quality, clean compressed air. Otherwise, those manufacturing facilities are doomed to costly rework, product recalls and a tarnished reputation.

“In semiconductor manufacturing, a small particle can ruin one of the die on a multi-die semiconductor wafer,” explained Dan Ryan, Engineering Manager, Parker Hannifin Corporation – Gas Separation and Filtration Division. “Even when it comes to things like painting automobiles, a few small, invisible particulates, depending on the makeup of them, can actually cause a visible flaw in the paint job.”

Proper air preparation significantly increases the process and production reliability of machines. Particles, water and oils in compressed air reduce the service life and functionality of components and systems. They also impair productivity and energy efficiency. In this article, a variety of air filtration and air treatment products are outlined and discussed, along with ancillary equipment like drains. Additionally, the article provides an overview of the compressed air purity classes defined by ISO 8573-1:2010.

Compressed air is used in more than 70 percent of all manufacturing activities, ranging from highly critical applications that may impact product quality to general “shop” uses. When compressed air is used in the production of pharmaceuticals, food, beverages, medical devices, and other products, there seems to be confusion on what testing needs to be performed.