RO/DI Filter

I was thinking about ways to save water yesterday and I think I may have come up with something. Tell me what you think.

Since an RO/DI filter removes all TDS and other contaminants can I hook a pump (one of the pumps used to increase pressure) up to the RO/DI filter and place it in a bucket filled with old tank water? And I can also run the waste water tube right back in to the bucket. Even if tank water would not work, what about doing this with tap water? There would be almost no waste water by doing this.

 

It would not work for long, the waste keeps concentrating to the point it eventually trashes the membrane. What you describe is being done now although slightly different with dual membrane systems.
I had a Spectrapure MaxCap dual membarne systemn which takes the waste from the first membrane and feeds it to the second one reducing the waste some and reusing the waste once.
Membranes must be flushed to work, there is no way around it and that is where the 4:1 waste ratio comes into play. You must keep that membrane surface clean of it begins to solidify and cake up causing failure.

 

How do you flush it?

 

Thats what the flow restrictor in the waste line is for. it provides the continous flushing of the membarne while it is in use. The so called flush kits you see have no proven value and as far as I am concerned only lighten your wallet. Until I can see some conclusive reports showing a benefit I would not bother.
Keep the waste ratio at 4:1 and you have no worries.