If we want to decrease the membrane area we have to increase the permeability of the membrane. These two variables are directly correlated. Since a higher permeability means that more gas per area can pass the membrane.​

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Just to give you an idea recently developed membranes can reach permeabilities up to about 1500 gpu. Two examples are:​

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- PolarisTM 1500 gpu
- Polyactive® 1600 gpu​

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Unfortunately, the permeability is not constant, but rather depends on the operating conditions like the humidity or the temperature. That means in order to minimize the costs it is necessary to chose the optimal operating conditions for the selected membrane.