Reusing reject water - how big a tank?

[Red Baron]

I'm thinking about reusing some of my reject water for my IBA but I only have room for a 300 gallon tank. Is that big enough to make a difference given that I'll empty it a lot faster and more often than my RO system comes on to make RO/reject? Can I gain some by setting my folats in the RO tank closer together so that the RO system comes on more often?

 

[I.B. Washincars]

I have 3 autos and 7 SS bays at my busiest wash. 2 of the autos are Mark VII GT-700s which have two HP pumps on each gantry. I use up all of my reject with it plumbed to just one pump on the least used auto. I have a 325 gallon tank. You will only lose water in the rare case that your product tank is nearly empty on a super busy day and the business stops instantly (started raining). In your case you could probably get by with a much smaller tank. I would size the reject tank by figuring how much reject you would produce if your product tank were completely empty. Put an overflow to drain in the case that it does overflow for some reason. Mine overflows if auto 3 goes down. In most cases the reject is used up as it is made, a large storage capacity is just not necessary.

I see no reason for changing your float settings in the product tank.

 

[washtubman]

I piped my reject directly into my rinse tank of one of my automatics. I put a drain hose then from the top of my rinse tank to the floor drain, so if my automatic isn't running the excess reject goes to the drain and doesn't overflow the tank. I don't always reuse it all, but it's simple and certainly helps.

 

[Waxman]

I used a 250 gallon 'tote' for ro reject. It's plumbed into my IBA feed tank. It has its own float and I have it set up to run along with city water so it mixes in.

I use up all the reject now and rarely lose any down the drain. Losing some this morning; it was busy yesterday and is snowing out now.

I will be running a detail job thru the auto to use up some reject in a few minutes.

 

[raisetheprice]

We have 2 300 gallon tanks for 2-autos only. At first the reject would overflow bc of the 2:1 ratio or so of reject to spot free. It was fine if we were busy enough, but like another mentioned sometimes business just stops due to rain, etc. To fix this problem, I particially closed off the city raw water supply at the pump station so that I'd pull more water from the reject tank with each wash. I also have a fresh water valve that feeds the reject tank should it get too low and starve the bladder pump that feeds the main pump stands. It's a little frustrating when one of the components fails, but well worth it in the long run. No sense in throwing away perfectly good water.

 

[dclark3344]

I just built a rack above my automatic pump stands that has a 200 gallon tank with an over flow. I ran 1 1/2 inch pvc pipe down to each of the water tanks for the automatic and put a shut off on each one. I then used a horse tank float valve that I purchased at Atwoods farm and ranch supply and I have it set at about 8 inches higher than the Walters city water float valve. This way I am using gravity and no more energy. The savings are substantial and well worth it esp when you have 8 self serves using RO. Generally the undercarriage does not even activate the city water float and by the time the soap is applied the tank has been refilled with RO reject water for the High pressure rinses, then you get to use more when the triple shine is being applied. We generally use all the reject water unless as stated earlier there is a sudden weather change and business stops completely.