RODI Question

[Yose]

I have a 2 RODI units. What if I were to have the effluent tube of the 1st unit drain into a 90 gallon container and use a booster pump on the container to feed the 2nd unit? Has anyone tried this? Any ideas?

 

[Kreeger1]

I think you could just run them in series, minus one ro membrane.

 

[Yose]

Ok... I'm not sure I understand. I was looking at having 2 rodi outputs from 1 water source. Wouldn't removing the the 2nd membrane just make it a carbon/sediment/di filter?

 

[Yose]

A shorter method of explaining the thought:

Effluent recycling via a 2nd ro/di unit.

 

[Dubbin1]

So you are wanting to run the waste water from the first unit into a 90g container and then take the water from that and run it through the second unit?

 

[glaudds]

Re: RODI Question

<a href=showthread.php?s=&postid=6499582#post6499582 target=_blank>Originally posted</a> by Yose
I have a 2 RODI units. What if I were to have the effluent tube of the 1st unit drain into a 90 gallon container and use a booster pump on the container to feed the 2nd unit? Has anyone tried this? Any ideas?

If I understand what your trying to do correctly, I would think you would be generating much more waste water with this setup. Much more efficient to use a DI cartridge.

 

[Yose]

<a href=showthread.php?s=&postid=6499722#post6499722 target=_blank>Originally posted</a> by Dubbin1
So you are wanting to run the waste water from the first unit into a 90g container and then take the water from that and run it through the second unit?

That is exactly what I had in mind.

<a href=showthread.php?s=&postid=6499771#post6499771 target=_blank>Originally posted</a> by glaudds
If I understand what your trying to do correctly, I would think you would be generating much more waste water with this setup. Much more efficient to use a DI cartridge.

I agree there will be a higher effluent discharge from the 2nd unit. It's source will be effluent but there should still be some good water drained from the ro. What do you think?

 

[Kreeger1]

I think thats a waste of water and energy, for cleaner water do this
you have 5 chambers
Run the first and second as sedimate
3rd and 4th as carbon
then to the ro membrane
then di
Erik

 

[glaudds]

The TDS in your waste water from the first unit will be very high. If you run the waste water into the second unit, you're resulting water from the second unit will have a higher TDS than coming out of your first unit. Remember the RO membranes only reject a certain percentage of the TDS. Hope that makes sense.

 

[Yose]

<a href=showthread.php?s=&postid=6499837#post6499837 target=_blank>Originally posted</a> by glaudds
The TDS in your waste water from the first unit will be very high. If you run the waste water into the second unit, you're resulting water from the second unit will have a higher TDS than coming out of your first unit. Remember the RO membranes only reject a certain percentage of the TDS. Hope that makes sense.

That makes lots of sense... Now I understand why it would blow through a di filter at lightning speed. I guess it's a better idea to just use the carbon/sediment stages in series, like kreeger had said... Get the TDS lower before the water hits the RO... Smart. Thanks

 

[Kreeger1]

Yeah, thats what Im going to be doing too, Doesn't waste anymore water but cleans it up better before it hits the ro membrane.
Erik

 

[glaudds]

This is what I would do. If you have three canisters before the RO membrane in first unit, run a sediment filter, then two carbon block filters. Then take two canisters from the second unit and get some refillable DI cartridges and run those post RO membrane in series. You can get those here...
http://www.airwaterice.com/product/GAC10NREN

When the DI resin wears out, it's much cheaper to refill with bulk resin than buying new DI cartridges.
You will have water with 0 TDS.