How much waste water does a RO unit produce?
 

Hello all I just picked up a Conqueror IV 4 stage Ro unit and I am planning on hooking it up as soon as I can get to a plumbing store. I have been doing some research and I found out they produce more waste then good water? Anyone be able to shed some light on this?

its suppose to be 3 to 1 or something like that. mine is exact opposite, it drips out waste and produces tons of good water but im in north van and my tap water is < 12 TDS

I'm lazy...the following is a cut and paste...I think you should be looking for a 4:1 ratio though, 4 parts waste to every 1 part of good water. If you're getting more good water to waste, I would say something is wrong with your filter...at least that's what me thinks :redface:

"The RO stands for Reverse Osmosis and refers to the chemical/mechanical method of filtering the water. Basically the water is forced through a semi-permeable membrane that allows water molecules through, but blocks most other organic and inorganic materials. This can only happen with a pressure differential from one side of the membrane to another. But the membrane is very delicate and would burst if presented with the normall pressures a normal filter cartridge endures. Thus the water flows across the membrane with only a moderate differential pressure. The second reason for the waste water is that since the pores in the membrane are very small, they clog easily. The flowing water across the membrane also flushes the membrane clean. Even so, most RO units have a method of flushing the membrane with full flow to clean it further."

Yes they will generally run from 2:1 to 4:1 depending on the input pressure and temperature.

4:1 with booster pump
8:1 without

you can get a valve to adjust the ratio (here), I have mine for 3:1

mine makes about 1 gal RO for 3 gal waste. tried calculating how much it would cost to with filters and membranes and waste water hopefully I got it right, it costs about $0.80 per gallon of RO water produced. biggest cost comes from the RO membrane.

Hum well I guess I will have to plumb a line into the sink drain. I was originally planning on putting it into a bucket, but after I make 5 gallons of water and have 20 gallons of waste, esshh! Thanks

Is this really true? Can someone verify. If this is correct, I think I should get a booster pump. why waste water!

I get about 3 Gallons waste to 1 gallon pure with a booster pump

Use wasted water for other stuff. Jdigital and I used it for our laundry. Now the waste is used to water plants around at my parents house.

Depends on what your source water pressure is in the first place. Before you go getting a booster pump, get yourself a pressure guage and measure your input water pressure. If it is 60 psi or better, it's a waste of money to add a booster pump.

3:1 without a booster pump

Seems like a strain on natural resources.

Like drinking bottled water... it takes 7 times the amount of water in the bottle to produce it.

If the few of you who mentioned it are recycling the water... good on yah... for the others that are dumping it down the drain... it's money out of your pocket everyday. Throw it my way instead.. I'll buy a fish ha ha!

Temperature makes a big difference too.
I had an inline thermometer on my household water supply just before the RO unit.
In the winter, sometimes the incoming water temp was below 5 C!
The RO membrane rejection rates (and GPD) are also based on an incoming temp of 23 C.
The colder the temp, the higher the rejection rate.
I have heard of some setups supplying the RO unit with a mixture of hot and cold water.

Mitch

I have a vertex which is suppose to be 1:1 but I've never checked so I doubt it. If you're concerned about wasting water many people store the waste water and use to for other purposes. If you can find a use for all the waste water then your ration will be zero.

Sounds like a great idea...I think I'll try that, just need another saddle valve and a T.

Water is cheap though,...All you have to do is tap it before your meter, not that I'm doing that...:whistle:

My water is included in my condo fees so I really don't see it.... But still its not good to waste something that many countries don't have. I will find a use for it... Maybe a mini ice rink on my balcony... :lol:

If you want to run 0 waste water, run your waste line back into your household supply. In that case you WILL need a booster pump.
Before hooking up that type of advanced setup check with the manufacturer to make sure that your RO unit can stand that higher pressure.

Mitch

That does'nt sound right. Never heard of that.

I lived in a condo townhouse in Ottawa for years and the water was also included in the monthly condo fees. That's the problem, if you're not on top of things, 'you don't see it' but our fees escalated every year in large part due to water usage. There was one water meter installed for every block of condo units which consisted of mainly 5 units per block. I was in a block of 3. Everytime there was a suggestion to install individual water meters, there was little to no interest. What you can't see can often hurt you, or your pocket book. In any case, pocket book or no, wasting a basic need for life such as water is never a good thing.