DIY high output Reverse Osmosis unit

[illumnae]

Thank you everyone for your advice so far! My tapwater tds is about 100 so it's not very high, so running 2 membranes in series is feasible. If the flow restrictors can be run in parallel then it seems the best setup for me would be to run 2x 400gpd membranes in series with 2x 1500cc flow restrictors in parallel. That would give me the 800gpd total output (maybe slightly less if there's some loss from flow restrictors being in parallel).

Moving on to the other issue on the booster pump, if the rationale that 2x 400gpd membranes in series requires only 400gpd flow restrictors, then wouldn't the same rationale apply that only a single 400gpd booster pump is required?

Anyone able to shed any light on what the pressure bypass column in the booster pump specification means? Will it auto shut off once my shutoff valve is triggered by my storage barrel float switch?

 

[a.t.t.r]

By my (half arsed) calculation your restrictor size is a lil low but with your low tds water you should be ok. You will be using about 1200 to 2000 gallons of water per day.


the bypass pressure is the pressure relief valve internally opening so the pressure does not go above that amount. The unit will not shut off by it self you will need to install a simple pressure switch on the clean water output after the ro unit but before your top off float (usually right after the auto shutoff valve)

 

[a.t.t.r]

You will need apx 5000 cc per minute on the booster pump. While the waste is the same you are producing about 1000 cc more water then a single membrane.

Again my bad math puts you at 5k cc a minute

 

[Buckeye Hydro]

Residential RO systems (regardless of if they also have a DI stage) generally range from a low around 12 gpd to a high of around 150-200 gpd.

Commercial RO's typically start around 500 gpd and go up from there.

A major difference between the two types of systems are the membranes they utilize, and how these membranes are configured.
Residential systems typically are sold to users without knowledge of their source water quality, and with no treatment of that water before it reaches the RO. That's why most residential systems sold by reputable dealers are set for a low recovery (i.e., a high concentrate to permeate ratio).
Commercial systems typically are sold to users where the source water quality is understood, and with all necessary treatment of the feedwater before it reaches the RO. That's why most commercial systems sold by reputable dealers are set for a much higher recovery (i.e., a lower concentrate to permeate ratio).

Russ

 

[illumnae]

Sorry I just had another alternative plan that I need some advice on. Let's say I use a simple 100 or 200 gpd rodi system for my awc, and I set up another storage tank for my freshwater tanks that only uses a simple 3 stage water filter without an ro membrane, would an auto shut off valve work with the 3 stage water filter to shut it off when the water storage tank is full (via a float switch) the same way that it does with an rodi system? The auto shut off valve would probably be connected like this?

 

[a.t.t.r]

Sorry I just had another alternative plan that I need some advice on. Let's say I use a simple 100 or 200 gpd rodi system for my awc, and I set up another storage tank for my freshwater tanks that only uses a simple 3 stage water filter without an ro membrane, would an auto shut off valve work with the 3 stage water filter to shut it off when the water storage tank is full (via a float switch) the same way that it does with an rodi system? The auto shut off valve would probably be connected like this?

If you have no ro you have no need for autoshutoff. The float itself will shut it down. The autoshutoff just prevents waste from being made when the clean water output is closed by shutting off incoming water

 

[a.t.t.r]

Sorry I just had another alternative plan that I need some advice on. Let's say I use a simple 100 or 200 gpd rodi system for my awc, and I set up another storage tank for my freshwater tanks that only uses a simple 3 stage water filter without an ro membrane, would an auto shut off valve work with the 3 stage water filter to shut it off when the water storage tank is full (via a float switch) the same way that it does with an rodi system? The auto shut off valve would probably be connected like this?

Why not use your waste from the ro to fill those other tanks ? (I assume those tanks being non ro won’t be used for a reef)

 

[illumnae]

If you have no ro you have no need for autoshutoff. The float itself will shut it down. The autoshutoff just prevents waste from being made when the clean water output is closed by shutting off incoming water

When I tried to do that previously, the pressure build up when the float switch is closed caused the hoses to pop off and water splashed all over the place from the tap (and that's the reason I switched to a larger rodi unit to service all the tanks instead of using tap water initially). The vendor who sold me the rodi unit also told me that without the auto shut off valve, the pressure build up when the float switch is closed would cause the rodi unit to burst. That's why I thought the auto shut off valve is able to somehow relieve the pressure when shutting off the incoming water.

Why not use your waste from the ro to fill those other tanks ? (I assume those tanks being non ro won’t be used for a reef)

I keep mainly blackwater tanks which require as low tds as possible - that's why I've been ok using ro for these tanks with just a pinch of remineralizer (still lower tds than my tap water)

 

[elysics]

When I tried to do that previously, the pressure build up when the float switch is closed caused the hoses to pop off and water splashed all over the place from the tap (and that's the reason I switched to a larger rodi unit to service all the tanks instead of using tap water initially). The vendor who sold me the rodi unit also told me that without the auto shut off valve, the pressure build up when the float switch is closed would cause the rodi unit to burst. That's why I thought the auto shut off valve is able to somehow relieve the pressure when shutting off the incoming water.

I keep mainly blackwater tanks which require as low tds as possible - that's why I've been ok using ro for these tanks with just a pinch of remineralizer (still lower tds than my tap water)

If the hoses pop off from the water pressure then they aren't secured enough and I would fix that, even if you find another solution for the shutoff. That's just an accident waiting to happen.