Zapping the problems out of winemaking filter slurry

Dealing with filter slurry from modern winemaking was a challenge for Rabastens Winery in France. Foodec decanter centrifuge technology from Alfa Laval proved to be a cost-slicing solution that also reduced environmental impacts.

Better solutions to known problems
Vinovalie is a group of four leading cooperative wineries in southwest France. Currently cultivating more than 10,000 acres, Vinovalie is the largest producer of red and rosé wines
in this important wine-growing area of France. This means the Group is constantly on the lookout for better solutions to problems both known and new.

Many wineries use earth filters (with diatomite or kieselguhr) for removing solid particles such as skins and pips from the grape must after the initial pressing. Diatomaceous earth is
a soft, naturally occurring siliceous sedimentary rock that in powder form is ideal as a filter medium because it is extremely porous.

However, this traditional form of filtering results in large amounts of effluent that wastewater treatment plants won’t accept because of the high concentration of solids (often up
to 40%), and also because the silica-based structure of the saturated kieselguhr makes it very abrasive for machinery and equipment in the plant.

This means that for many wineries the only viable path for disposal of this slurry involves trucking the slurry away for spreading on fields. The high water content makes this slurry
heavy – and therefore expensive – to transport, and it’s generally both difficult and costly to dispose of. There are also substantial undesirable environmental impacts involved.

But Rabastens Winery dealt with their filter slurry problem by using Alfa Laval Foodec decanter technology, and reports a 50% saving on their transport costs.