Calculation of the solubility of mixed gases in water
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I’m seeking help from experts: how can one calculate the solubility of a mixed gas in water? The solubility of pure gases in water can be found in manuals, but how is it possible to calculate it for mixed gases? For example, the solubility of oxygen in water and the solubility of ozone are known, but it is not clear how to calculate the solubility of a mixture of oxygen and ozone in water (with a volume ratio of 9:1). Also, how to calculate the solubility in a solution? Please give some guidance!
For slightly soluble gas mixtures, whose concentrations in the solution are very low, they can be calculated based on their respective solubilities and partial pressures, or individually using Henry’s law. For example, for the oxygen and ozone mixture you mentioned (with a volume ratio of 9:1), assuming the total pressure is P, the solubility of oxygen = 0.9 x the value given in the manual x (P/P0) ； Ozone solubility = 0.1 x manual value x (P/P0). Where: P0 is the partial pressure of the component corresponding to the solubility value in the manual. When the gas mixture contains components with high solubility, the effect of solution concentration on solubility must be taken into account; generally, phase equilibrium calculations are required to obtain solubility data.
Using the Aspen flash model, input the gas composition, water temperature, system pressure, and the amounts of the two streams.