Is 80 Pa Really a 'Huge' Pressure in Desalination Plants?

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The discussion centers on the pressure used in desalination plants, specifically questioning the claim that 80 Pa is a "huge" pressure for reverse osmosis. It is clarified that 80 Pa is significantly lower than the typical pressures required, which are usually in the hundreds of psi or around 80 bar. The confusion likely arises from a misunderstanding of pressure units, as 1 bar equals 100,000 Pa. Participants agree that the correct pressure for effective desalination is in the range of megapascals (MPa), not Pascals (Pa). Overall, 80 Pa is not considered a substantial pressure for this application.
lioric
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I went to a desalination plant and the guy explaining reverse osmosis says that they force water through the membrane at a huge pressure of 80 pa

But I was wondering and that is less than 1atm. And it's like an 8kg placed on a 1 square meter space. I thing a 65kg human gives more pressure since the feet is smaller than 1 meter squared.
What am I missing here
 
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I know that. I'm asking this is 80 pa a lot of pressure? Cause that guy in the plant said so and I asked him if he's sure it's pa and he said " yes 80pa " and said it was a " huge" pressure.
 
The guy at the plant is incorrect. It takes pressure of the order of many hundreds of psi to force the water through a membrane depending on the salinity. 80 Pa is as you noted is pretty low. Think of the order of MPa.
 
gleem said:
The guy at the plant is incorrect. It takes pressure of the order of many hundreds of psi to force the water through a membrane depending on the salinity. 80 Pa is as you noted is pretty low. Think of the order of MPa.
Thank you
 
lioric said:
I know that. I'm asking this is 80 pa a lot of pressure? Cause that guy in the plant said so and I asked him if he's sure it's pa and he said " yes 80pa " and said it was a " huge" pressure.
As the link shows, the pressures used are in the range of 80 bar rather than 80 Pa.
So it may be than someone was confused about units.
 
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