Industrial Utility Efficiency    


A major poultry processor and packager spends an estimated $96,374 annually on energy to operate the compressed air system at its plant located in a southern U.S. state.  The current average electric rate, at this plant, is 8 cents per kWh.
Technological trends in plastics manufacturing are driving the costs of production down. In industrial PET blow molding specifically, two innovative techniques have had major impacts over the last 15 years: “light weighting” the plastic bottles, and recirculating high-pressure compressed air. Both have helped to improve the energy efficiency of PET blow molding by reducing compressed air requirements dramatically.
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.
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. 
ISO 22000 is a food and beverage (F&B) specific derivative of ISO 9001, a family of standards from the International Organization for Standardization that details the requirements of a quality management system. It is a quality certification that can be applied to any organization in the food chain — from packaging machine manufacturers to the actual food processing facilities.
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.
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.
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.
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.
As readers of this publication know, there are many ways to save energy in industrial compressed air systems. One common supply side technology is the variable frequency drive (VFD) of the compressor. It is well-documented that positive-displacement compressors with VFDs provide cost-effective savings in comparison to inlet modulating, load-unload, and variable displacement control.