Industrial Utility Efficiency    

End Uses

At a Midwest window manufacturing plant, the cooling process for the plastic frame pieces, after leaving the extruder, was critical to process productivity and quality. Too much cooling air (or not enough cooling air) would generate scrap and rejected product. The plants’ 17 extruders and 55 separate blow-offs in these lines had similar cooling stations at the cooling boxes. They consisted of about three hoses at each exit frame angled down to the extruded piece moving past it. The compressed air flow was controlled by a manual control valve set by an operator. The operator used his experience to control the flow delivered and thereby control the product quality.
Over the years, analyzing compressed air system operation and efficiency has gone under various names and taken many different shapes and forms. You may know these as; Assessments, Audits, Studies, and Surveys, but in all cases the compressed systems are analyzed using techniques, such as metering and measuring, to assess the system’s performance and identify opportunities for improvement. The problem is that the results of these activities have varied widely; leaving the end-user to try and determine what is usable, credible and implementable. This has led to a lot of “no actions“, resulting in assessments, audits, studies, and surveys being put on the shelf to collect dust.
This facility is part of a corporation producing molded plastic products. There are many injection and extrusion molding processes. The factory was spending $94,934 annually on energy to operate their compressed air system. This system assessment detailed seven (7) project areas where yearly energy savings totaling $53,191 could be found with a minimal investment of $4,170.
BC Hydro is a sponsor of Compressed Air Challenge and one of two Canadian utilities represented on the Board of Directors. BC Hydro’s Power Smart Compressed Air Optimization program helps customers assess how their air system is working, helps with project implementation costs and provides for onsite training of plant personnel. The following profiles tell how two of their customers discovered excellent savings through the application of low cost measures.
The PET industry is in a state of flux right now. A number of new bottle blowing facilities are being brought on-line. They are in the “discovery” phase right now as they realize how challenging the required compressed air systems are to manage – from an energy efficiency standpoint. The average high-volume stretch blow molder (SBM) working with PET usually has 2,000 to 4,000 horsepower of installed air compressors with the related energy costs running between $1 to $4 million per year. This typically represents 35-40% of the facilities’ total energy bill.
Compressed Air Best Practices interviewed Gregory Rhames, Asset Reliability Manager/Energy Manager at Verallia. As background, Verallia is the packaging division of Saint-Gobain. Verallia employs 15,500 people globally and makes about 25 billion glass bottles and jars each year. We employ 350 people at Madera where we produce about 1 million wine, champagne and sake bottles per day.
Bottling companies and breweries, in California, are benefiting from a three-step system assessment process aimed at reducing the electrical consumption of their compressed air systems. The three-step process reduces compressed air demand in bottling lines by focusing on open blowing and idle equipment, and then improves the specic power (reducing the energy consumption) of the air compressors.
Compressed air system refinements have cut operating costs at a Milk Plant located in Winnipeg Manitoba, Canada by 62%, for annual savings of nearly $30 000. The improvements were made following a compressed air audit that recommended consolidating two compressed air systems into one, installing a variable speed drive compressor, and making a handful of additional basic improvements.
Power Smart® efficiency measures for compressed air systems at Tolko’s paper mill and sawmill at The Pas are saving the company more than $125,000 a year.  
Air-operated double-diaphragm (AODD) pumps are known for their positive attributes of handling fluids that are heavily laden with solids, abrasive materials, shear sensitive liquids (paints and coatings) and the ability to pump soft solids without damaging the product. They are also popular because they are lightweight, portable and easy to use due to their pneumatic power.
This pharmaceutical plant spends $265,100 annually on energy to operate the compressed air system at their facility. This figure will increase as electric rates are projected to be raised from their current average of 7.7 cents /kWh. The set of projects identified in the compressed air system assessment could reduce these energy costs by $139,300 per year (52%).