Generally used in the processing of musts, flotation is a process in which the solid parts are separated from the liquids and brought to the surface with the help of air or nitrogen bubbles and particular floating agents, such as bentonite, sol silica, or gelatin.

In addition to the basic model, with a single centrifugal pump, the FLTB flotator (F-32), the Spadoni range dedicated to this type of filtering process offers two other models with the following characteristics:

• The FLTS centrifugal double pump flotator (F-34), which improves on the basic model by integrating it with:
  • a second flotation pump;
  • glass viewing window at the entrance;
  • an impregnating tank.
• The FLT flotator with double centrifugal pump (F-33), the top-of-the-range version, which enhances the FLTS model with:
  • an insulated and heated gelatin tank;
  • a control thermostat;
  • an alarm probe to indicate that gelatine has finished;
  • a dosing pump with relative pipes.

Industries

• Wine

Operating principles

The difference in density between solid particles and the liquid that contains them is the principle exploited during the flotation filtering process.

In the must, most of the particles have a density similar to the liquid in which they are immersed. For this reason, it is necessary to both add clarifiers (bentonite or gelatins) that aggregate to the solid masses, and introduce different kinds of gas, mainly nitrogen or air, which, by binding to the insoluble particles, facilitate their rise to the surface, and the consequent  separation from the clarified liquid, which is then transferred to a second tank and sent towards fermentation.

Clarification by flotation has found, in recent years, an increasing use in the wine sector, and is currently considered an effective method to improve the quality of the wine, because of the many advantages it offers:

• Rapidity: it can be implemented immediately after pressing, and the product can be processed immediately afterwards;
• low and sustainable costs;
• improvement of musts obtained from grapes of different origins;
• optimisation of workspaces;
• elimination of tartaric acid loss, and consequent removal of tartrates in the cleaning phases;
• reduction of dregs volume.

General characteristics of the FLTB flotator with a single, centrifugal, pump

• Prefilter with inlet valve;
• 3Kw product centrifugal pump;
• micrometric tap for product regulation with dissolved flotation gas;
• pressure gauge, to manage flotation pressure in the impregnation tank;
• pressure reducer;
• air/nitrogen filter;
• microdosing valve;
• air flow meter;
• sampler valve;
• tap with Venturi effect (suction), to introduce the gelatin;
• glass viewing window for must output control;
• electrical cabinet;
• structure and piping in 18-10 stainless steel (AISI 304);
• skid with wheels in 18-10 stainless steel (AISI 304).