So I was sitting in a class and we were talking about
reverse osmosis and the pressure needed to force H2O through the organic membrane, approximately 26 ATM of pressure. Thats alot of pressure and I know that the powerful pumps are expensive and require alot of energy to produce the
water. As a diver, I know that 10 meters of
depth equal a pressure of 1 ATM, so you can achieve 26 ATM by going 260 meters down in the ocean. Well, even if you did have a tube with only air and a membrane that was down that far, the energy to bring the clean
water up would roughly equal the
power and
pump requirements of forcing water at 26 ATM. Not useful at all. What could
work to bring up the water is a series of capilaries (hundreds even) that would through capilary action bring the fresh water up without any energy requirements at all. Could
work, if the system was anchored firmly to the ocean floor and balanced properly. Not really useful, though because of the huge system needed to produce a fairly small amount of water per time frame. What could be a good idea, if in a situation that would nececiate a small amount of fresh water is if someone was DIW and out in the ocean. What could work is a small, metal device that has a membrane and air inside, could be lowered to 260m and left there for the pressure to fill the tube with fresh water. When recovered, there would be a 1 way valve that would discharge the air (as the pressure increased in the tube from air expanding) and leave the collected fresh water inside for drinking. I know, its an odd idea and has limited application, but its 2am and my mind is wandering. And Im a little drunk.