Engineering360: "New Ways to Separate Your Methane from Your Carbon Dioxide"

Since Carbon Dioxide is roughly 100 times more soluble in water than Methane(see images below), I wonder how efficiently a water spray in a pressurized tank of the gases could operate. It seems like this would beat the efficiency of cryogenic separation if done at large scale. Spraying the water would vastly increase the surface area through which the carbon dioxide would dissolve. Remove(pump out) the excess fizzy water as it collects at the bottom of the tank. This would also leave other combustible gases like CO in the tank since its solubility is also way lower in water than carbon dioxide. Does anyone know why they do not do it this way ? I suspect that this could operate well at cool ambient temperatures so it should be easy to implement.

thewildotter

A quick search retrieved this(slightly rearranged to fit ...thanks, ETB):

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The capacity, solubility (mol/kg) might seem favorable. It might have a speed limitation (dissolution, mol/s).

Right. That is why I specified spraying the water(increases surface area), pumping out the fizzy water(avoid saturation), pressurizing the tank(partial pressure stuff), and generally outlining a continuous process(no batch size limitation interacting badly with time required to come up to pressure.) Your observation that it might proceed too slowly is valid and needs checking for specific design requirements. Good comment. Perhaps someone could run the numbers on some straw-man example to see if it ever wins against the discussion alternatives. I have the same problem this suggested approach might have, I would take too long to produce results. I realized the solubility advantage and felt it might trigger someone else to slog through the details of some nominal swag of a design. I have no experience with quantitative calculations of speed of dissolution for different temperatures, surface areas, pressures,etc. so I would have to study a bunch before I would be able to do my own swag.

Is anyone out there already fluent and game for this quest ?

thewildΩtter ®!