Abstract: The present invention relates to the field of measurement devices, specifically to devices for measuring pressure and flow as well as derived quantities, and in particular provides a sensor device for in-line measurement of superficial gas velocity, froth depth, apparent density and holdup in flotation cells, which comprises: a first tube; a second tube; a first valve connected to said first tube; a second valve connected to said second tube; a first pressure meter connected to said first tube; a second pressure meter connected to said second tube; a first mass flow meter connected to said first valve; and a second mass flow meter connected to said second valve. The present invention also provides a system for in-line measurement of superficial gas velocity in flotation cells.

Abstract: The present invention relates to functionalized hollow glass microspheres for recovering fine hydrophobic particles, and to their preparation method. The invention also relates to a system for carrying out the method for preparing the functionalized microspheres, to a method for selectively recovering fine material and, lastly, to the use of the microspheres in the separation of, inter alia, minerals, micro drops of organic materials, plastics, and pollutants.