The Heinz Innovation Centre in Nijmegen Heinz has brought together a number of European research activities, making this the second largest R&D centre of Heinz in the world. The machines require high quality compressed air, where in the original specifications was spoken of one large compressor however, ALUP had a better suggestion.
Frans van Leeuwen, Senior Sales Engineer at ALUP, explains how the “food-grade” compressed air market develops. "It is a clear trend that the demand for higher quality compressed air increases," according to van Leeuwen. "Many companies with their R&D activities for product development usually have modest and often specialized production facilities. In terms of compressed air, this means that they need one or more smaller compressors with frequency controlled speed and state-of-the-art filter and dryer systems. With this, the demand for high quality compressed air that meets the strict BRC-food requirements for example, such as with Heinz, can be met flexibly but also profitably. ALUP can anticipate to this because we have all kinds of oil-free and oil-lubricated compressors in our assortment. Today it is especially important to look very closely at the need for compressed air and the way and intensity of how this compressed air is used. Modern compressors are available in many capacities and the trick is to find just the right mix for the application. Eventually that proved to be the big challenge at the Heinz Innovation Centre."
In the specifications for the compressed air installation at Heinz, initially a single variable speed 55 kW compressor was scheduled. According to Paul van Veggel, Sales Project engineer at Wennekes, this is not unusual, but in this particular case it was not optimal. “Fact is that in this Heinz Innovation Centre the production is not continuous on all lines. That means that the demand for compressed air strongly fluctuates. We believe that with the choice for a compressor some things are leading and those are especially energy consumption, flexibility, quality, reliability and maintenance sensitivity. The purchase price also plays a role, but of all the factors this has the least impact on the Total Cost of Ownership (TCO). Energy and other operational costs do, since in the TCO they cover over 92%. That is why we advised to install not one large, but two smaller frequency-controlled screw compressors. After consultation with ALUP we installed two RLR 40 EV oil-injected screw compressors of 30 kW."
Why oil injected and not oil free, which you would expect in a food-application? “This has mainly to do with reduction of the operating costs,” according to Frans van Leeuwen. “Oil injected screws are more cost-effective, but obviously we will use a food-grade lubricant. It is also important for energetic reasons to work with dry air. That is why we chose for a dew point driven adsorption installation. Furthermore the system is now redundant and maintenance is more effective because you can work on one machine while the other one is fully functioning and vice versa. So that also saves money.”
The compressor installation at the Heinz Innovation Centre is equipped with two 900 litre buffer tanks instead of one large one. Why is that? “The choice for two tanks has to do with a more compact build and further optimisation of the adsorption installation,” Paul van Veggel replies. “We placed one buffer tank before the adsorption dryer and the other one after it. Therefore you hold, as the adsorption dryer is busy regenerating, sufficient air reserves in the buffers to complete the regeneration process, if the compressors shut off by the decrease of demand. Pre- and post-filters filter the oil from the air, while the moisture is caught in the first buffer tank for the greater part and is automatically discharged.
Finally Wennekes installed everything perfectly, what also goes for the pipeline network. The main line is executed in 89 mm stainless steel pipe, where the complete net is divided into sections which can be closed per “string”. “The compressed air pipeline is mainly executed in stainless steel and on completion tested and found 100% free of leakage,” underlines Paul van Veggel finally. Heinz also wanted the pipeline system to be as optimally as possible, taking the food requirements into account. Hence the choice for metal and in this case stainless steel, because that way you will never have to deal with corrosion both internally and externally.”