Food & Drink Process & Packaging Issue 17 2018 - Page 12

Spray Drying, it’s all about the Nozzle… Most modern day Spray Drying plants use a centrifugal Spray Nozzle to inject an atomised droplet into the drying chamber – but how important is that Spray Nozzle? Very, actually. The right nozzle maintained correctly can improve your yield, decrease your downtime and increase your output. In this short article I hope to give you a few pointers when caring for your Spray Nozzle. Always have a full set of nozzles cleaned, assembled and ready to go in the dryer. If these are attached to a spare set of lances, all the better. There is nothing more costly than having an issue mid production and having to pull a nozzle without having a spare to drop straight in. This also aids in unnecessary damage to the Swirl rapid clean down and start up turnaround Chamber and Orifice Disc, components times. which are expensive to replace. When running a CIP operation with the Polished inlet on the Orifice worn away? nozzle in situ, replace the nozzle head for So what; as long as it is still a smooth a CIP adaptor. Do not use concentrated profile leading to the bore, your spray acids to clean tungsten carbide nozzle pattern will not be affected! components, this breaks down the binder in the carbide ultimately reducing the Check your orifice size and keep note. life span of the components. We always recommend an organic citrus based cleaning agent heated in an ultrasonic bath, using a soft bristle brush to work the built up product from the components. Always replace all the seals in the Spray Nozzle after each production run. These nozzles run at extreme pressure in most instances - temperature, chemical attack and physical handling, can compromise the seals which may result in an unexpected When you strip a nozzle down with Check your Spray Nozzle orifice, even if the intention of reusing components it is brand new! OEMs have a nasty habit such as the Orifice disc, check and of handling Orifice Disc components in make a note of the orifice size. As the batches, this causes them to bang and bore size increases with wear, compare crash together which in a surprising it against your production sample/yield. number of cases can cause damage to If you know what size the Orifice is when the nozzle orifice, usually in the form of your yield starts to decrease, you can a ‘chip’. - This will cause a ‘streak’ in the make the most out of your spares and spray pattern which will affect your yield. start to plan for the replacement of the Spray Nozzle components before a costly change occurs in your production run. nozzle failure. Breaking up components. Often when Most good nozzles require a hand tight material has cooked inside and bound If you would like any support or further only assembly (when specified) – for these, the carbide components together – do advice on caring for your nozzle do not use tools! The pres ɔ͕́ѕЁѕѕѼ͕Ʌєѡ͔ݥѠեаMɕ̰MɅ她1̰)