Re: [Killietalk] R/O Question

[Wright Huntley <jwwiii at pacbell_net>]

Larry Botkin wrote:
> While I was just setting at my desk contemplating the new Fishroom 
> (building) design, I started thinking about water volume, storage and 
> water pressures, etc and that lead me to a good question for the 
> "experts"on Killitalk.
>
> Considering the volume of waste water outflow to the R;O water generated 
> what would be the upside/downside of placing another R/O unit on the 
> waste water outflow ? 

It would not work without an energy-wasteful booster pump. The process 
relies on water-line pressure to work, so the outlet must be at pretty 
low pressure or the first unit stops working.

> I'm going to be moving to an area that 
> periodically has water restrictions put in place and I'm looking for 
> ways to maximize R/O output and minimize the waste water. How about 
> stacking 3, 4 or more ? ( To go the obvious extreme)

In some areas, the waste water can be run back into the underground 
aquifer, so really isn't wasted (except for your water bill). In most 
areas, there is certainly no need to waste it. It usually is about 
90-95% the same as your tap water, so is excellent for drip-irrigation 
and similar uses.

Since you probably will have a couple of carbon filters on it, it should 
be free of chlorine or chloramine, so it can even be saved in a reserve 
tank and used for change water in your fish tanks. Many Nothos, Fp. and 
Aplos adore harder water, so no need to throw it away. Only some of the 
rainforest fishes need more RO to dilute harder tap water down to a 
lower tds.

I just ran my RO unit outlet into a tap into my main patio 
drip-irrigation line, in Santa Clara, and the plants did fine with 
whatever the 450 ppm tap water was turned into by extracting about 20% 
for RO (probably about 495 ppm).

David mentioned raising the inlet temp. to get more efficiency. It 
works, and a coil of tubing in the attic or other warm place, between 
tap and RO unit, can improve RO efficiency by a fair amount. How about 
next to the coils or on top of your fishroom refrigerator?

Wright

--
Wright Huntley -- 760 872-3995 -- Rt. 001 Box K36, Bishop CA 93514

           Mencken's maxim—every election is a sort
             of advanced auction of stolen goods.



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