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Easy RO reject water question

Etowah
I

Indiana Wash

Member
OK, I am copying Galen's RO reject water reclamation setup. My question is this. After I get the tank in, how do I get the reject up into the tank? Does it exit the RO with enough pressure to carry it into the tank 5 feet above it??? I would bet it does, but I don't know. If not, how does anyone else get it into the tank? Would it require yet another holding tank and float and pump???
 
I have a question for the people who collect the reject water. What is the payback time from the investment in the tank, pump, and plumbing? We'll not count the labor. Just curious.
 
Mac,

In our area a system like this is regarded as a reclaim system which allows operators to stay open when drought restrictions are enforced as they are right now. So even if the ROI is not that great it allows washes to stay in business.
 
mac said:
I have a question for the people who collect the reject water. What is the payback time from the investment in the tank, pump, and plumbing? We'll not count the labor. Just curious.
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Well Mac, it all depends on the price of water/sewer. Here, it is rather expensive at about 14.00/thousand gallons. Let's just pretend that we throw nine gallons of water on a car during an IBA spot free rinse cycle. If it is a "traditional" RO that rejects 2 gallons for every gallon used. That's 18 gallons going down the drain, or basically a quarter. If we can build a reclaim system for less than 1K, it will pay for itself in 4K cars. So in my example at a decent wash payback can be in just a couple of months.

In addition to the water used for production some systems "flush" their membranes quite often. My Pur Clean wastes a ton of water.

I really like gravity to do the job of the system. However, I didn't have gravity at one wash so I took a standard vertical tank and added a cheap sump pump (less than $100)I had on hand that I originally bought at Lowes. I then built a box that held a relay with a 110V coil. I powered that coil off of one leg of my pump motor starter. Any time the big pump on my IBA is running the sump pump is also. I put that in as a temporary measure about a year ago and it is still working.
 
Indiana - yes, should have enough pressure to go uphill. I assume your RO generation process is the same whereas you use a booster pump to create the water pressure against the membrane. Good water goes into your tank and bad water goes up the hose to where you want it. Mine goes up at least 10' to my upstairs holding tanks.

mac - you mention payback. If you already have an RO system in place, your only extra material is a holding tank and plumbing to/from it. Maybe I'm missing the point of your question. If you're current RO system is just throwing reject water down the drain, then think about what the reject water really is. For me, it's softened, de-chlorinated water. That's water worth keeping and using for rinse, it's far better than tap water.
 
No doubt it takes awhile to pay it back. My town estimates water and sewer costs at 1 cent per gallon. I use a 250 gal. tote to recover the reject from R.O., so every time I fill it and use it I save $2.50. I think the plumber fee plus pump and materials was around $500 and I got the tote for free.
 
I use an extra tank that sits right next to my holding tanks for the autos. I tie the 2 tanks together with a hose and lower the float in the original tank. I do not need a system to transfer the water in this way.
 
I forgot to mention, since my reject water tanks sit upstairs (above the auto pumps) I just gravity feed them into the pumps and use it as the rinse water for the autos only.
 
Waxman said:
No doubt it takes awhile to pay it back. My town estimates water and sewer costs at 1 cent per gallon. I use a 250 gal. tote to recover the reject from R.O., so every time I fill it and use it I save $2.50. I think the plumber fee plus pump and materials was around $500 and I got the tote for free.
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Takes a while??? No matter how you calculate it, the payback is a few months. If you can find anything else with that quick of a payback, let me know!
 
Thanks for the feedback. I asked because the ones I've seen here in FL have been somewhat elaborate, with a submerged stainless pump. Of course that elaborate system was sold by a reclaim company, not a DIY project.
 
Indiana Wash said:
Takes a while??? No matter how you calculate it, the payback is a few months. If you can find anything else with that quick of a payback, let me know!
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Only if you have an IBA.
I dont have the #s handy right now, but I actually put a meter on my RO reject and my softener reject. Multiplied gallons by cost of water+sewer, did a quick estimate on cost of materials...
Bottom line was NOT a few months. (I do not have an IBA). But with an IBA I agree its a good project, I would do it.
 
PaulLovesJamie said:
Only if you have an IBA.
I dont have the #s handy right now, but I actually put a meter on my RO reject and my softener reject. Multiplied gallons by cost of water+sewer, did a quick estimate on cost of materials...
Bottom line was NOT a few months. (I do not have an IBA). But with an IBA I agree its a good project, I would do it.
Click to expand...

YES, I meant if you have an IBA. If you don't, it wouldn't be worth it. I think that was said earlier.
 
You can't keep all of it for sure. The "brine rinse" cycle is where it flows salt. If you could divert the backflush and settle rinse cycles to storage you'd have some savings. If I managed to save those cycles I'd get about 250 gallons from each regeneration.
 
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