Air Knife Conversion
As part of our energy efficiency services, Advantiv are constantly striving to help clients reduce their energy use and carbon footprint. Compressed air is a very expensive commodity to produce, so Advantiv make every effort to help clients reduce and optimise its use where ever possible.
During a site visit to discuss ways in which a client’s compressor usage could be reduced, Advantiv identified an air knife being used to blow metal swarf off a production line at a large steel wheel manufacturer. The original system comprised of a 0.75” galvanised pipe with 4mm diameter holes drilled at 25mm intervals along its length supplied by compressed air at 7 bar. The process runs for 10 hours per day, 5 days per week, 48 weeks per year, the clients electricity cost was £0.065 per kwh. The estimated cost of running the air knife with the compressed air was just over £51k pa
Added to this, using compressed air with blow off nozzles or worse still open ended pipes can cause major fluctuations in the main line supply and other equipment not to function correctly. In certain applications lubricating oil can also cause contamination of the end product.
Advantiv highlighted that the clients system could easily be converted to an alternative system using radial blowers as opposed to the compressed air, therefore freeing up a large proportion of the compressors capacity whilst also providing a more stable and controlled supply of air to blow off the swarf with exactly the same vigour.
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Compressed Air
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ACI System
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Total Flow (CFM)
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1410
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Total KW
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7.5
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Total Flow (L/min)
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39931.2
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Total Kw hours
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7.5
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Cost for 900L air
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£0.01
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Cost for 1kw/hr
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£0.05*
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Cost per min
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£0.35
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Cost per hour
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£21.30
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Cost per hour
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£0.38
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Weekly Analysis
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Working Hours/days
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10
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10
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No of shifts per week
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5
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5
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Cost per week
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£1,064.83
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£18.75
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No weeks per year
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48
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48
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Cost per Year
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£51,111.94
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£900.00
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Differential running costs
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£50,211.94
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*(6.5p per kw/h)
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The new system was specified and designed with the help of Advantiv’s partner supplier Air Control Industries (ACI) one of the world leaders in air knife technology. ACI’s air knife system was supplied in a modular format allowing easy installation by the client on site, its aluminium and stainless steel construction ensured it was robust enough for the harsh environment it was to be fitted in.
The running costs for the new system were calculated at £900 pa giving an annual saving of just over £50k in running costs, the payback on the purchase of the new equipment was only 23 days!
This system re-design and some other work carried out as part of our compressed air leak management programme has enabled the client to turn off a 110kw compressor, the client has been so impressed with the system and savings that further air knifes have now also been converted to ACI’s blower system.
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