Industrial Utility Efficiency    


A small pulse crop and seed processing facility located in Canada has upgraded their facility compressed air system to accommodate the expansion of their production capacity.  While completing this project the facility has learned some valuable lessons about sizing and maintaining lubricated screw air compressors and compressed air drying equipment.
This is a corn mill processing cornstarch, sugar, and other byproducts. Ambient air is contaminated with extremely high levels of dust due to the manufacturing processes and material handling. Average electric rates at the plant are $0.04 / kWh. The actual plant electric cost for compressed air production is $553,630 per year.
This food & beverage plant is a large (500,000 sq ft) meat processing plant with twenty packaging lines and nine palletizers. The compressed air system is supplied from three separate rooms with seven individual lubricant-cooled, single and two-stage rotary screw compressors. The plant has four blower purge desiccant dryers designed to deliver a - 40°F pressure dewpoint.
It was the Fall of 1997 in Germany. I was just another guy working in the German compressed air industry. East Germans were still being looked down on - seven years after unification, the Euro was launching in little over a year - forcing marketing managers like me to scramble and create unified european Euro pricing strategies, European Cohesion Funds were flowing out of Germany and into the Mediterranean (not literally), and the diminutive Mercedes “Smart Car” was the cool car for space-challenged urban dwellers. With this going on, you can imagine the surprise of the compressed air industry when compressed air was featured in “Der Spiegel”, a “Newsweek-like” weekly magazine in Germany with national distribution.
This article reviews portions of an audit report of a compressed air system in a food industry factory located in the U.S. Although the audit explored different supply-side options the client should consider to improve dynamic efficiency, we will focus on the demand side of the system for this article.
This brewery is a relatively large operation with nine production lines plus a keg line. There are five bottle lines and four can lines. Operations in the plant include palletizing de-palletizing, filling, packaging operations, and brewing. Annual plant electric costs for compressed air production, as operating today, are $693,161 per year.  If the electric costs of $43,016 per year associated with operating ancillary equipment such as the blower purge dryers are included, the total electric costs for operating the air system are $736,177 per year.  These estimates are based upon a blended electric rate of $0.06 /kWh.
  In an ideal world, industrial air or gas supply lines would be free of particulate, water, oil and other contaminants. In the real world, however, supply lines typically deliver some contaminants along with the air or gas they were designed to carry. Left unchecked, these contaminants will cause efficiency losses, maintenance headaches and the premature failure of pneumatic components.
This meat processing and packaging factory spent an estimated $203,640 annually on energy to operate the compressed air system at their Midwestern facility. Based on the air system operating 8,760 hours per year, the group of projects recommended below could reduce these energy costs by an estimated $107,522 or 47% of current use. In addition, these projects will decrease compressor maintenance costs. Estimated costs for completing the recommended projects total $21,900. This figure represents a simple payback period of 2 months.
Using suction cups and air-driven vacuum pumps is a preferable gripping and handling method of corrugated cardboard materials and boxes in carton-machines like case/carton erectors and rotary cartoners. Robot based applications, like palletizing and de-palletizing, are other examples where the best practice technology for gripping and handling is by suction cups and air-driven vacuum pumps.  
This facility operates one of the largest compressed air installations in industry, with 21 4000 hp process air and five 750 hp instrument air centrifugal compressors to support large-scale aerobic fermentation and related processes that require large volumes of oxygen.  
A recently completed energy efficiency improvement programme at the Britvic Beckton bottling plant has resulted in substantial energy savings and a positive impact on the company’s carbon emissions allocation.