Liquid—foam system

A process for breaking foam floating on a liquid medium contained in a first tank in which floating foam is broken in foam breaking equipment, comprising the steps of:

• providing a foam conveying means within said first tank, said foam conveying means having a funnel shaped upper inlet adapted for the passage of floating foam and a downward outlet, a sucking means operatively connected to the foam conveying means and having a screw-shaped element adapted to be rotatably driven;
• providing a first exhaust gas tube defining a channel, said first exhaust gas tube being positioned relative to said foam conveying means for conveying gas from the foam conveying means, said first exhaust gas further having a first opening located above the funnel shaped upper inlet and a second opening located in the foam conveying means at least 20 cm below the level of the funnel shaped upper inlet of the foam conveying means;
• rotating said screw-shaped element to suck foam downwardly into the funnel-shaped upper inlet;
• conveying foam downwardly through said funnel-shaped upper inlet towards the sucking means;
• at least partially defoaming the foam conveyed into the foam conveying means;
• conveying gas released from the foam in the defoaming step into said channel of said first exhaust gas tube;
• and
• conveying foam which remains after passage through the foam conveying means to one of said first tank and a second tank different from said first tank.