Dealing with the vegetation water which is the waste product from olive milling poses many problems. Due to the large quantities of organic matter, especially polyphenols, the COD values are extremely high. These values can be reduced biologically, by using oxygen to encourage the biological breakdown processes.

The effectiveness of these processes is strictly dependent on the possibility of transferring the right amount of oxygen to the liquid. The transfer of oxygen to the liquid depends on the temperature and the liquid/gas contact surface.

CHIGI44® is a system that produces gas microbubbles 0.75-1 mm in diameter regardless of the supply pressure (up to 6 bar). The huge contact surface generated (6000/8000 m2/m3) has the following positive effects:

  • The large contact surface allows a level of gas exchange never previously achieved.
  • The small size of the microbubbles allows them to remain in the liquid for longer, further improving gas transfer. The dwell time is further extended by the convective flows, which keep the microbubbles immersed.
  • The microbubbles also trigger a flotation effect, which carries suspended solids and oily micro-inclusions to the surface, from where they can easily be removed.