Reverse Osmosis Seems Slow and Wastes Water- Really Needed for City Water?

[davealicious]

I think the point is that you can control the ratio. It's not about the membrane, its about the flow restrictor and design of the system. Your system uses an Auto Flush and a high pressure flow restrictor, thats why it produces a 2:1 ratio instead of the typical 3 or 4:1 ratio. the use of a higher restriction at the flow restrictor has a tendency to clog membranes, well, your system has an auto flush to help rinse the membrane.

As i said, lots of reef keepers manually flush their membranes to prolong the life. Thats what your system is doing.

hell, you could just plug the outlet and it would provide a 0:1 ratio until the membrane becomes totally clogged. at which point you could attempt to flush it and possibly get some more life out of it.

its a simple trade off.

 

[ScrewyBrewer]

I think the point is that you can control the ratio. It's not about the membrane, its about the flow restrictor and design of the system. Your system uses an Auto Flush and a high pressure flow restrictor, thats why it produces a 2:1 ratio instead of the typical 3 or 4:1 ratio. the use of a higher restriction at the flow restrictor has a tendency to clog membranes, well, your system has an auto flush to help rinse the membrane.

As i said, lots of reef keepers manually flush their membranes to prolong the life. Thats what your system is doing.

hell, you could just plug the outlet and it would provide a 0:1 ratio until the membrane becomes totally clogged. at which point you could attempt to flush it and possibly get some more life out of it.

its a simple trade off.

Ahh got it and thanks for explaining. There is a timer on my RO filter or a flow meter that automatically triggers the flush cycle after every ~20 minutes of steady use. And I remember when installing the filter the instructions called for inserting a flow restrictor based on the pressure of the source water at the inlet.

 

[mongoose33]

Ahh got it and thanks for explaining. There is a timer on my RO filter or a flow meter that automatically triggers the flush cycle after every ~20 minutes of steady use. And I remember when installing the filter the instructions called for inserting a flow restrictor based on the pressure of the source water at the inlet.

Every 20 minutes? Wow.

I have an RO system, but I let it run for hours as it fills the aquatainer I use. I flush it at the beginning of use, and again at the end. But not every 20 minutes. I wish I had a system that would do that for me. But there's only so much money, and I have other more pressing brewing items on my need/want list.

 

[davealicious]

I wonder @ScrewyBrewer considering the flush frequency are you actually getting 2:1? is that counting the flush water?

I'm with you @mongoose33, I use a 35 gallon rotomold container and fill with water as a holding tank, I use a RO/DI system and its helpful to have 35 gallons on hand for brew days, or for my saltwater reef tank. I've thought about installing a UV light inside the tank to kill off anything that hangs out in there but generally i run it empty then refill when i'm gone for a weekend as i found out that my 75gpd system cannot produce 75 gallons in a day, i'm much close to 25-30 per day but thats starting with water with a TDS content around 450.

 

[ScrewyBrewer]

I wonder @ScrewyBrewer considering the flush frequency are you actually getting 2:1? is that counting the flush water?

I'm with you @mongoose33, I use a 35 gallon rotomold container and fill with water as a holding tank, I use a RO/DI system and its helpful to have 35 gallons on hand for brew days, or for my saltwater reef tank. I've thought about installing a UV light inside the tank to kill off anything that hangs out in there but generally i run it empty then refill when i'm gone for a weekend as i found out that my 75gpd system cannot produce 75 gallons in a day, i'm much close to 25-30 per day but thats starting with water with a TDS content around 450.

Honestly I've never bothered to check it, looks like the auto flush runs every hour. I plugged in the SpectraPure CSP RO 90-AF reverse osmosis water filtration system and took their claims at face value.

 

[day_trippr]

fwiw, my autoflush does an 18 second flush once per hour...

Cheers!