ENERGY EFFICIENCY
Air compressors form an important part of a plant’s infrastructure, which is why it is important they run efficiently.
Is that hissing noise the sound of money going up in smoke? An air audit of your air compressor systems could save you a lot of money. Food & Beverage Industry News talks to ELGi’s Greg Gillespie.
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ne thing that never fails to amaze Greg Gillespie is the amount of times he walks into a manufacturing or processing plant and hears hissing. It immediately tells him that they are running an air compressor or a bank of air compressors. It also tells him that the company is throwing money down the drain. That hissing sound is either one, or a series of leaks, coming from the compressed air system. Gillespie, who is the national sales manager for air compressor manufacturer ELGi, said that in some cases companies are literally throwing thousands of dollars down the drain every year. Not only that, but when he hears that tell-tale sign of hissing, he knows that doesn’t include the ones he can’t hear. “I’ve walked into a lot of different places – and to be fair my ear is tuned for it – and I immediately
hear all the air leaks,” he said. “And I’ll say to the person on site, ‘you’ve got a few air leaks’. They generally reply, ‘no we don’t’. They don’t hear them because it is background noise to them.” What he encourages people to do is stay back for five minutes after the work day when everything is quiet. He’s confident that they will then hear the noise. “And the thing is, if you can hear an air leak, it’s a large one. There will be quite a few air leaks you’ll never hear without ultrasonic equipment, especially if they are inside a piece of equipment,” he said. Gillespie said the culprits in these leaks are usually the same range of suspects – hose clamp connections, seals failing, and worn fittings. And he’s not saying that maintenance managers have to fix them all at once. He knows that, especially in the some of the bigger
28 Food&Beverage Industry News | March 2020 | www.foodmag.com.au
food and beverage manufacturing and process plants, it can be a big job. A maintenance plan is needed and such a plan is not something whereby a leak is fixed once and then forgotten about. It will depend on the size of the factory and plant and how many compressors are working. He acknowledges it would be a big task to do it all in one go, so maintenance managers would set about a plan to go and rectify the leaks starting with the biggest one first. Then they would just do a constant, weekly check. But what is the cost? “If someone has an air audit done then they start to realise that ‘holy heck, we’re leaking thousands of dollar per annum’,” he said. “The more plant and machinery you have in place, the more the leaks are going to cost your bottom line. “If you have a small place with a 2.2kW compressor, then that cost isn’t going to be that high. But if it
is a larger factory with 100kW of installed compressor power, then it will cost a lot. “I know of a place that has three 55kW machines. One of those 55kW machines pretty much services air leaks. If they fixed their air leaks they can turn one of their compressors off. Do the maths of 55kW of power running all day. They operate 24/7 – not at full capacity – but they are aware of it. I’m sure if you put all the numbers down in front of the people running the place, suddenly it wouldn’t be too hard to fix.” Education is also a key ingredient. A lot of places he visits think the air is free. Quite often Gillespie will see people “sweeping” the floor with an air gun. It’s convenient, it’s quick, but it does come at a cost. “Some think it is quicker doing it that way because it reduces the labour cost involved,” he said. “I
