Low-pressure Carbon Dioxide (CO₂) dissolver

CO₂ in gas form can be dosed directly into a pipe, however, if there is not enough water movement and contact time between the dosing point and the first limestone contactors, the following risk should be considered:

• CO₂ will likely accumulates at the top of the pipe.
• CO₂ may or may not dissolve.
• Undissolved CO₂ may scape through the first limestone contactors without reacting with the calcite.

Therefore, the low-pressure CO₂ dissolver has been designed to meet the following criteria:

• 99% CO2 dissolution before the water enters the first limestone contactor
• Simple design
• No moving parts
• No maintenance
• Low pressure system
• Can be shipped anywhere in the world and installed without special equipment
• Reliable for very remote areas

The low-pressure CO₂ dissolver system consists of the following elements:

1. The dissolver tank, that operates under the following conditions:
   • The CO₂ is dosed at counter-current
   • Water velocity inside the dissolver is such that the bubbles are not dragged away
   • The tank is pressurized
   • Has a special CO₂ diffuser that provides very fine exudation in a very large diffuser area.
   • The dissolver has internal devices that facilitate the mixing of CO₂ microbubbles.
   • Made with materials and adhesives approved for use in drinking water.
2. The CO₂ diffuser, that has the following characteristics:
   • Large diffusers with fine pores and minimal differential pressure requirement.
   • The distance between the pores of the diffuser allows an even distribution of the micro-bubbles.
   • It has a design that allows the application of substantial quantities of CO₂.
   • Made with materials and adhesives approved for use in drinking water.
3. The bubble visor:
   • Located at the same height as the diffusers to check a correct operation.

This development is based on a joint research project between the FCCA and the S.G. Of Water of Barcelona financed by the European Union.