Oxygen cones (e.g. Speece cone / oxygen cone) are pressurized contactors where water and pure oxygen meet under elevated pressure. That raises oxygen solubility and gives high transfer efficiency — common when pure O₂ is used in RAS, raceways and intensive land-based systems.
When cones are used
- High oxygen demand and limited space for aeration.
- Pure-oxygen strategies (generator, tank or cylinder).
- Need for precise DO boosts in side-stream or main flow.
Design points
- Pressure, residence time and gas/water ratio govern transfer.
- Too much pressure/gas can cause gas supersaturation — see TGP/supersaturation.
- Degassing and pressure reduction after the cone must be controlled.
- Often combined with LHO, diffusers or tank dosing depending on hydraulics.
Operation
Monitor DO before/after, oxygen pressure and leaks. Calibrate DO sensors at critical points. The cone does not replace good hydraulics or a sound overall oxygen strategy (air first, pure O₂ as additive where it pays).
See also