Water nano-carbonation by CO2 infusion into submersible and pipe-flow nanobubble generators: The rise and fall of dissolved CO2.

The CO₂-bubble-based carbonation of water using established methods is very energy-intensive with the status quo of mechanical bubble generation, and there is rapid loss of CO₂ from the dispersed (bubble) phase in water, due to larger bubbles sizes in the micro-, meso- and macro-range and their associated instability. Instead, the "nano-carbonation" of water, by CO₂ fine bubbles (including CO₂ nanobubbles) provides for longer-lived levels of dissolved CO₂. The present research details how the use of both submersible and continuous-flow nanobubble generators can boost levels of dissolved CO₂ far above Henry's-Law level, and tracks longevity and decay of the dissolved-CO₂ levels in the water. In particular, in the case of the submersible fine-bubble generators, both mechanical and novel electrostriction (electric-field) approaches are used, whilst in the case of pipe-based generators, hydrodynamic approaches are used for fine-bubble carbonation, with optional application of electric field to boost longer-time dissolved-CO₂ levels. The decay times for the dissolved CO₂ were assessed, which were a great deal longer – magnitudes – than without nano-carbonation, owing to the nanoscale CO₂ keeping the overall dissolved-CO₂ concentration higher with slower Fick's-Law release. [ABSTRACT FROM AUTHOR]