Is Ro waste water safe to drink

[Nemos Janitor]

I see...

When the RO unit is running, how much water do you plan to produce. In other words, will the RO unit run stop start stop start as water is used or will it produce 100l+ at a time?

 

[Shaun88]

Guys, here's the fact, as a Physiologist, and knowing the physiology and chemistry, Reverse Osmosis def:
"The process in which pure water is produced by forcing waste or saline water through a semipermeable membrane" Thus the membrane being the determining factor. Def of osmosis: "The tendency of a fluid, usually water, to pass through a semipermeable membrane into a solution where the solvent concentration is higher, thus equalizing the concentrations of materials on either side of the membrane"

So, reverse osmosis water, even if not completely TDS at 0, is not safe to drink due to the following factor in a physiological way:
If TDS water has less TDS than body disolved TDS, free water (in this case RO water) enters the body, osmosis will occur and minerals will be moved over from the body to the mineral deficient water through the membranes, by means of energy utilizing cells to transport these minerals, of the cells so to make or try create an equilibrium. Thus removing minerals ie. calcium, potasium etc. from the body system, just to create an osmotic equilibrium and in turn depleting the body of it's nutrients/minerals.

NO, one would not die by drinking RO water occasionaly, but in constant or only source, it could have adverse effects. Mineral depletion in the human body can have several effects, some being fatal.

For the price of water, rather drink bottle or tap water, much cheaper and safer than risking the ill effects of TDS free/low water.
RO water for household use has got a re mineralizer to replenish minerals needed in H2O to make it physiologically safe.

Just my opinion, use it, dont use it. All up to the consumer...

Hope this helps!!

 

[Quintin]

I see...

When the RO unit is running, how much water do you plan to produce. In other words, will the RO unit run stop start stop start as water is used or will it produce 100l+ at a time?

It will be both, I suppose.
100L + to fill up the tanks initially and then a start / stop process to top-up as the water evaporates.

 

[Nemos Janitor]

My thoughts and experiences with those type of float switches used as a ATO have normally ended in disaster. I have seen many a tank pumped with RO water when the float switch fails or the pipe comes off wiping the tank out. I would recommend that one tops up from a reservoir that is manually refilled or automatically filled only when one is present.

I also have one of those float switches on my RO system but the RO system works a lot different to to how you plan to install yours. (Yes the float switch has failed a few times before) My system is capable of producing 1500l of RO a day. Because stop /start water production shortens the life of the membrane and water that is within the RO unit becomes anaerobic and the bacteria blocks the membrane. It is always best to flush the membrane before production and discard the first few liters of water before one uses the good water. My system has this facility built in. But then i paid R7k for the basic unit, if i remember correctly, and then added some of the automation.

Hope this gives you some food for thought in your automation design.

 

[Nemos Janitor]

With regards to the remineralisation of RO water for drinking. I would have thought that one would get sufficient irons and minerals from the foods we eat and other beverages we drink.

 

[Quintin]

My thoughts and experiences with those type of float switches used as a ATO have normally ended in disaster. I have seen many a tank pumped with RO water when the float switch fails or the pipe comes off wiping the tank out. I would recommend that one tops up from a reservoir that is manually refilled or automatically filled only when one is present.

I also have one of those float switches on my RO system but the RO system works a lot different to to how you plan to install yours. (Yes the float switch has failed a few times before) My system is capable of producing 1500l of RO a day. Because stop /start water production shortens the life of the membrane and water that is within the RO unit becomes anaerobic and the bacteria blocks the membrane. It is always best to flush the membrane before production and discard the first few liters of water before one uses the good water. My system has this facility built in. But then i paid R7k for the basic unit, if i remember correctly, and then added some of the automation.

Hope this gives you some food for thought in your automation design.

Thanks for the info.
I think I will stick my original plan with the automation as I'm away on business out of the country for at least 2 weeks a month and I can't expect the wife to carry buckets of water around to top the tank up on a daily basis or can I expect her to do the water changes if required. So automation is the best option.
R7K is a bit much for a unit but then again, you get what you pay for.

Sorry for hijacking the thread.

 

[mariusmeyer]

@Quintin, shutting off the pure line will not stop the waste line from running. You have to cut the supply to the RO unit itself. The only way to do this as far as I know is with a solenoid connected to a float switch or 2 float switches for redundancy. But this automation can cause chaos if it fails.

 

[Keanan]

@Quintin, shutting off the pure line will not stop the waste line from running. You have to cut the supply to the RO unit itself. The only way to do this as far as I know is with a solenoid connected to a float switch or 2 float switches for redundancy. But this automation can cause chaos if it fails.

Yip, just ask @Perky pets superstore about the flooding they they had with doing so.

 

[mariusmeyer]

and yeah damn i made 5liters RO and there was about 30 Liters of waste water is that right?

@CarlosF Your wastage is extremely high. I tested mine yesterday and for every 3L of RO I make I collect 5L of waste water. So thats a ratio of 1:1.667. My tap water is TDS of 92, unit is 2 years old and I have never replaces any filters/membrane. But I do flush the unit everytime before I use it.

 

[Keanan]

@CarlosF Your wastage is extremely high. I tested mine yesterday and for every 3L of RO I make I collect 5L of waste water. So thats a ratio of 1:1.667. My tap water is TDS of 92, unit is 2 years old and I have never replaces any filters/membrane. But I do flush the unit everytime before I use it.

Then you must be lucky, my waste water is also much more than my RO water. Haven't done a test yet to see what the ratio is but if I must guess its about the same as Carlos's. Using a waterboy unit.

 

[Quintin]

@Quintin, shutting off the pure line will not stop the waste line from running. You have to cut the supply to the RO unit itself. The only way to do this as far as I know is with a solenoid connected to a float switch or 2 float switches for redundancy. But this automation can cause chaos if it fails.

Thanks for the info but I have this covered.
Below is a picture of how it works and this is the same process they apply to the R/O units sold for home use.

And this is the float switch I will be using.
Water and air pressure.
No 12V float switches with magnets driving a pump or any of that malarkey.

 

[Suhayl]

Reafhead, you saying that all the bottle water companies should close down as they not safe to drink?

 

[CarlosF]

Thanks @mariusmeyer for the info I don't think I have flushed mine how do you do that? This is my first RO unit, its a vertex unit

 

[Reefhead]

Reafhead, you saying that all the bottle water companies should close down as they not safe to drink?

No I am saying that bottled water companies add minerals back into the filtered water before they sell it to you
The RO water that comes out of the RO machine we use in this hobby has no minerals in it

 

[Visser]

Thats a lot of watse. My tap water is 92 and I only get about 2L waste for every L of RO. And my filters are old as well.

The waste will have higher TDS as it will contain all the minerals that got rejected by the membrane. By better quality I mean that certain stuff such as chlorine will get filtered out by the carbon filters.

Just to add something interesting to your thread, the TDS of my tap water in brits is 1750 before filtering with ro & after filtering, about 1-2.
TDS reading of my waste water... Take a wild guess...
4970!!!
So i wouldnt even think about drinking my waste water, lol!
My tap water comes from a borehole. Ive had the water tested previously, & if i remember correctly, the calcium was 1143mg/l & also had notable traces of sulphur & phosphorus it it. The lab guy indicated on the report that it was even unusable for animal consumption.
Keeping that im mind, i would really not suggest you drink water with too much dissolved solids!!!