CO2 increases the tendency of the beverage to foam, which impairs the quality of the goods. An Italian winery has therefore been using a particularly low-pulsation, hygienically safe rotary lobe pump of German manufacturer Netzsch.
This T.Sano pump guarantees not only the desired pressure over the entire pumping distance – and thus the quality of the wine – but also reliably prevents the un-wanted development of foam. In this way, more precise dosing and better barrel emptying is achieved.
Only wines with a carbon dioxide overpressure higher than 3 bar at 20 °C are fully sparkling wines (spumante), while those from 1 to 2.5 bar are semi-sparkling wines (frizzante). To guarantee the desired amount and pressure of car-bon dioxide, the entire production facility of the winery in Piedmont therefore operates under controlled pressure conditions up until the moment of isobaric bottling. Nitrogen is used as an aid to create still wines at 0 bar and particularly fizzy wines at 5 bar according to variety. This protects not only the special composition of the wine, but also prevents undesired foaming, which can make complete batches unusable in extreme cases.
The function of the pump is based on two rotary lobes, which counter-rotate, thus transporting the medium from the suction to the pressure side. Since pumping is performed purely according to the positive displacement principle here, there is no possibility of pressure fluctuations or shearing forces. This type of pump does not pressurise the medium but rather only pumps against the existing counter-pressure – 1 to 8 bar in this case. In addition, the specially designed internal geometry of the delivery chamber keeps any pulsation at a very low level so that values similar to those of complex spiralled, multiple rotary lobes can be achieved, despite the smooth rotary lobe. In this manner, a gentle, continuous delivery without any turbulence that could lead to foam is guaranteed and the organoleptic characteristics of the respective wine remain reliable.
To meet food safety guidelines in addition to the economic aspects, all components used in the T.Sano rotary lobe pump that come into contact with the medium are designed in stainless steel. A toothed belt transfers the torque from the motor to the rotary lobe while synchronising the rotation of the rotary lobe. It runs completely free of oil, which means no extra lubrication and oil change work is required, but also that environmental damage is absolutely excluded.
Thorough cleaning is required so that nuances of taste do not mix when different varieties are used. To make this as easy as possible, the interior of T.Sano is designed to be free of dead spaces in a flow-optimised manner. Mechanical seals are evenly flush with the rear side of the rotary lobe. The rotary lobes themselves stand out from the competition due to smooth surfaces on all sides, as they are not screwed into the pump chamber, but rather fixed externally using quick-release components. In this way, product residue has nowhere to adhere and the pump can be flushed completely in a residue-free manner manually or using the CIP method.
Netzsch is presenting this pump at Anuga Food Tec 2018 in Cologne.