N F 270 Membrane

[philkasza]

We got a new nf 270 membrane this year and was wondering what is the highest pressure we can run without passing sugar and what is the highest concentration we can go without passing sugar. Is the pressure or the high concentration more prone to pass sugar?

Thanks Alot, Samuel

[Bucket Head]

I wanna say its 10-12% concentration, or maybe its 12% and over that they start to pass sugar? I don't know what p.s.i they go up to. The Atlantic RO company website lists the performance stats. for the Dow/Filmtec membranes.

[Mark]

I was told by the owner of Ecochem that a caustic wash will cause the pores or whatever they are called, to increase in size for hours after the wash. An acid wash right after will shrink them back down. He said the first high flow membranes were made by damaging a true RO membrane with caustic. I don't know how true that is but he said some of the sugar passage is caused by the after effects of a strong caustic wash.

[halfast tapper]

A friend of mine ran nf 270's for about 6 years never passed sugar at 12 percent and 350 psi. No problems .