The Aquaturbo® FRED is designed to re-entrain fat and a thick floating sludge layer, but no light sludge. The backflow impeller will constantly fill the volume above the downdraft impeller, to limit the aspiration of air. The surface water, including the fat and sludge layer will be sucked into the downdraft SCREWPELLER®, which will create a powerful flow downwards. Next, this flow will bend against the bottom of the basin and will be radially directed in all directions towards the basin side and back up to the surface. Thanks to this optimal flow, the basin volume will be mixed.

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