Re-routing Waste RO Water so Minimal Water Wasteage ? ?
- Thread starter furface
- Start date
Stacking membranes would be the way.
furface
Active member
Ooh you little legend you ! !
Vinny Kreyling
Premium Member
You can also go with a 2:1 ratio if your water supply is Soft Water.
I did it with Spectrapure, they have tests to check the water then a new flow restrictor.
I did it with Spectrapure, they have tests to check the water then a new flow restrictor.
BeanAnimal
Premium Member
Smaller flow restrictor (Higher number) equates to lower waste. That puts more stress on the membrane and the output TDS is higher (more DI use)
What the 1:1 system does is "auto flush" the membrane frequently during water production. Still hard on it, but less than just letting it scale up.
What the 1:1 system does is "auto flush" the membrane frequently during water production. Still hard on it, but less than just letting it scale up.
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I run a dual membrane in series ( 2 x 75gpd) and I'm on well water but I do have a booster pump that keeps it about 65-70psi. I think I lost about 5psi on the guage when I added the second membrane.
furface
Active member
I have discovered now, as I bought the unit a while ago that it is a 5 stage 150 Gallon Per Day Unit with dual membrane I believe run in series as I only have 1 waste. Water pressure is 50psi without a booster. I can buy the booster. Is it worth fitting a 3rd membrane ? Would this cut my waste water by another 50% ? ? And is it a rule of thumb to be 80psi ? It just really irks me the amount of waste Water.
Thanks
If the waste line from one membrane goes into the input of the other membrane , then they are in series. If you get a booster pump, add another membrane, reduce your flow restrictor - alone or combined they each will reduce waste water. Unfortunately, waste water is an unavoidable consequence of reverse osmosis. Personally I'd start with the booster pump - 50psi is borderline and not that efficent. Production should go up and TDS should go down. Win win.
furface
Active member
Yeah, the booster pump was always going to be needed. Booster pump it is for starters ! ! Thanks Kharmaguru ! !
furface
Active member
Yeah I plan on putting whatever waste water there is into some garden water storage bays to water the garden. I just remember hearing a. While ago about a way to reduce your waste water significantly and improve production of RO water so a win win
mtnbike101
Well-known member
My concern with running two membranes in series versus parallel is that you are inserting high TDS waste water into the second membrane thereby reducing the lifespan of the second membrane. I have mine in parallel with a booster pump and pressure is around 80 psi.
BeanAnimal
Premium Member
Parallel membranes do not reduce waste (in fact may increase it due to pressure loss over the membranes).
Series membranes reduce waste by ~50%
Yes the second membrane sees a bit higher inbound TDS - but this should not be an issue with reasonable source water. If you are shoving 600 TDS into the first membrane, then yeah the second will take a bit of a beating... but really both are taking a beating anyway.
Series membranes reduce waste by ~50%
Yes the second membrane sees a bit higher inbound TDS - but this should not be an issue with reasonable source water. If you are shoving 600 TDS into the first membrane, then yeah the second will take a bit of a beating... but really both are taking a beating anyway.
BeanAnimal
Premium Member
In theory it will work - but simply running a more restrictive flow restricter (lower number) will reduce waste. You just need to power flush (bypass the flow restrictor) the membrane after every run to keep buildup at a minimum.
furface
Active member
Yeah, I’ve read a heap about it now. My ro unit already has 2 membranes so I’m going to run wit. That for now and see how I go. Whatever I do there will some waste bug I do want to reduce it.
BeanAnimal
Premium Member
I think there is a valve at BRS that will cycle the waste bypass on startup and then every hour or something during operation. Not a bad idea.
I am almsot done with my own controller... but far more complex than most people would want to undertake.
I am almsot done with my own controller... but far more complex than most people would want to undertake.
An Apex, or other controller, should be able to control a solenoid to perform the flushes.
BeanAnimal
Premium Member
I was going to use the P4 to do it… but decided to build a stand alone unit…Touch screen, pressures, etc.
