Reverse Osmosis "Waste Water" for Irrigation

[hillhousesawdustco]

I have a Reverse Osmosis (RO) filtration system for brewing because I have extremely hard water off my 90 year old hand dug well. I generally do ten gallon batches and mix the strike water 50/50 between "tap" and RO, and then fill the HLT back up with RO for the sparge. So I go through quite a bit of RO for a brewday, and I brew lot.

I'm not sure what the exact ratio of pure RO water produced to mineral-rich waste water is at 50 or so psi, but it seems to be quite a bit. 4 gallons waste to 1 gallon usable water maybe?

I'd like to reuse the water for irrigation- I would plan to simply reroute the waste line from my drain to a 55 gallon rain barrel and then use that to drip-irrigate my garden. Does any one else do this?

The waste water will obviously be pretty alkaline, but I'm not on city water so there is no chlorine or chemicals or anything. Watchall think?

 

[MNDan]

It will only be 25% more alkaline - no problem at all...

 

[DubBrew]

I use mine in the washer and on plants regularly without any problem.

 

[hillhousesawdustco]

That's what I figured, just saw some "oh my god don't do that" posts on aquarium and similar sites. I think those folks were concerned about chemicals/metals/whatnot being concentrated in the waste.

In my case rainwater should hopefully dilute the solution even further (not that it ever rains here in July or August....when I need it to)

 

[Chrisl77]

Minerals yes chemicals not so much. The waste water from an ro system comes right before the water passes through the membrane. The water passes through a set of prefilters before the membrane that includes atleast 1 carbon block filter.

 

[hillhousesawdustco]

More reason for mine to be uber-filtered then. It goes through three carbon filters first. Thanks for the help!

 

[Hackwood]

I work with Softeners and ROs as a profession and have had MANY people do exactly this. There are many uses and the garden/lawn seems to be the most popular. You also turn your RO into zero waste that was. GO GREEN! haha