In Cannon Artes’ ZeroGas® thermophysical deaeration dissolved gases are removed by reducing the partial pressure of oxygen and carbon dioxide over the liquid surface by replacing air with steam.
In order to establish the equilibrium for oxygen and carbon dioxide between the liquid and vapour phases the contact area is increased by spraying the liquid and making it fall on a proprietary structured packing. Steam is employed as stripping and heating medium because of the reduced solubility of gases at higher temperature.
Therefore, operation at pressures higher than atmospheric enables the establishing of more favourable equilibrium conditions because of the decreasing solubility of gases at increasing temperature.
Cannon Artes’ proprietary ZEROGAS® degassing process is achieved in the deaerating tower where make-up water is atomised on a set of special “structured packing” that increases the contact surface between water and steam.
According to the design capacity and steam flow, the deaerating tower may be arranged on a vertical or horizontal geometry, so that a larger mass and heat transfer surface is implemented.
Cannon Artes can provide also spray-type deaerators that combine the deaerating and storage sections into just one tank with a very efficient design leading to compact size and reduced weight.
Cannon Artes is also a partner for the specialists of Heat-Recovery-Steam Generators providing Integral Deaerators that could be installed directly on the LP drum of the boiler with the advantages of using the steam produced within the drum itself and saving an additional storage section. This is a critical application since the steam flow within the deaerating tower is driven just by the pressure loss across the mass transfer section (and by the differential temperature since the system is in liquid-vapour equilibrium).