Technical Yearbook 2023

JUNE

The pros and cons of pumping options for cellars By Charl Theron

Centrifugal pump

Pumps are one of the essential pieces of equipment in cellars because winemaking is a process of transforming solids into a liquid form. The latter’s specifications can however differ considerably. A fluid transfer is a complicated process due to the variation in the characteristics of liquids. The following parameters influence the choice of pumps, which contribute to the (un) suitability of individual pump types: • Minimisation of shearing and agitation during transfer • Oxygen exposure • Tolerance to solids and sediment • Self-priming • Portability

• Ease of operation • Cost-effectiveness Centrifugal pumps

Centrifugal pumps spin an impeller in a housing. The latter is designed to direct the fluid from the impeller to the exit nozzle. Centrifugal pumps do not create high-pressure exits, limiting potential rupturing of containers or hoses. However, they are rough on the liquid pumped and thus not

suitable for finished wines. Moineau (Mono-) pumps

These pumps operate by rotating a helix-formed rotor in a helix-shaped elastomeric rotor. The advantages of this type are positive displacement, high solids resistance, flow rate variability, easy cleaning, good portability and large volume suitability. It is costly, but this should be balanced with hundreds of thousands of litres of transfer capacity.

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TECHNICAL YEARBOOK 2023