Industrial Utility Efficiency
If there was ever a place where manufacturers can save energy using compressed air and make measurable gains toward sustainability, it’s with pneumatics that power a seemingly infinite variety of machines and processes.
Machines for filling milk or juice must often work around the clock. Given the critical importance of uptime, Elopak opted for Aventics food-compliant pneumatics when developing its E-PS120A - the first fully aseptic filling machine for gable top packaging. With an output of up to 12,000 cartons per hour, disruptions and downtime are not welcome with the aseptic filling machine.
A flour based frozen foods manufacturer orders a compressed air efficiency audit. The audit establishes the cost of compressed air at \$0.27/1000 cubic feet. The study finds the 116 pulse jet dust collectors represent the greatest opportunity for compressed air demand reduction and energy cost savings. A dust collector optimization study/service is suggested and the customer agrees to proceed. In this facility, pulse jet dust collectors are used to filter dust from raw materials entering the plant, for conveying and mixing of ingredients, and for the final packaged finished products leaving the plant.
In the last ten years, the design of pneumatic systems has changed dramatically, mainly due to developments in the technologies that create them. Pneumatic manufacturers’ online tools for sizing components have evolved, the fieldbus systems are ever-changing, component designs are constantly improving, and network devices such as the Industrial Internet of Things (IIoT) have reshaped the industry. All these advances play a large role in optimizing the efficiency of pneumatic systems, but the age-old practice of routine maintenance must not be overlooked. This article will focus on proper air compressor sizing, proper pneumatic component sizing and predictable preventative maintenance.
Figuring out the energy savings for the switch from pneumatic to electric tools requires an estimate of energy use for each case. The effect of replacing a few tools in a large compressed air system may be too small to detect using power monitoring on the air compressors. However, it is still a good practice, and when part of a larger program to reduce air consumption, the combined efforts will amount to something measurable. Another positive aspect may be that reduced compressed air use frees up needed air compressor capacity.
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.
The advent of manifold mounted, plug-in pneumatic valves has been a boon for machine builders. It allows them to mount complete valve packages in a safe and secure location on a machine. Using a D-sub connector, serial interface module, or similar single-point wiring system, all of the electrical control outputs can feed into one location on the manifold, greatly simplifying the wiring. Plumbing issues are reduced, since a single air pressure line can be used to feed a common pressure gallery. The same advantage applies to the common exhaust gallery. No longer would both a plumber and an electrician be required to replace a valve, since any valve can be replaced without disturbing electrical connections or plumbing lines.
Currently, and for good reason, much attention is being focused on the conservation of energy. Compressed air, like electricity and gas, is an energy resource. It has often been referred to as the third utility. As with all energy sources, our global environment demands that it be conserved and used wisely.
Responsible companies are looking at ways to not only reduce their energy consumption, but to make their production more efficient. This is a great general business practice, but how can you be sure that what you are doing has positively impacted the bottom line? More specifically, what can you implement that is repeatable as a best practice to save energy, and better yet, what can you implement that can be used to retrofit various machines across your floor? One solution is found in upgrading to modern pneumatic valves capable of saving energy by reducing compressed air consumption
A plastics molding plant had engaged us to conduct an ‘on-site’ Energy Assessment of their facility. The annual ‘spend’ for electricity, natural gas, and water was about \$3.2 million for this modern 275,000 square foot, fully air-conditioned facility. During the Review, several opportunities were identified and delineated in lighting, HVAC, process ventilation, the water systems and energy supply contracts. However, the most significant savings were in their compressed air system.
Machine builders aiming to improve the energy efficiency of their machines tend to focus on using energy media other than pneumatics (typically electro-mechanical or hydraulic) since pneumatics, as traditionally applied, is viewed by some as inefficient due to factors like leakage and over-pressurization (i.e.: supplying a higher pressure in an actuator to accomplish a task which is endemic in practice). But they shouldn't, with its low cost of ownership, pneumatics when properly used remains a viable and many times preferable energy source for a given application. When generating and using compressed air, it's true that there are many places in the system where energy can be lost, however targeted measures within a comprehensive energy saving concept can prevent these losses and significantly reduce energy consumption at the machine level.
