A pneumatic method and apparatus for causing the rapid recirculation of a liquid between a plurality of containers 10, 11 by adjusting the pressure of a gas exerted within each of said containers to superatmospheric, atmospheric and subatmospheric pressures, thereby avoiding the passing of the liquid...http://www.google.fr/patents/US4408960?utm_source=gb-gplus-shareBrevet US4408960 - Pneumatic method and apparatus for circulating liquids
Pneumatic method and apparatus for circulating liquids
