What to do with RODI waste??? - Page 3

mike31154 · #21 06-10-2010, 03:43 AM

Quote:

Originally Posted by jzz30tt

Waste water runs into a 70+ Gallon Retention tank. Shur-flo pump to a small pressure tank plumbed as an expansion tank tee'd into the supply for the main toilet in the house. Valves on both feeds to isolate the toilet from either the house supply or the RO waste supply when the other is in use. Also plumb a high level overflow to the drain in the case of the waste water filling the retention tank. Can also be used to run other things but the more usage needed the bigger pump and therefore more expense in supplying the water for those uses from the retention tank.

Scott

Welcome to the forum. That's a pretty slick solution you've summarized. Any more specifics on the parts required? Would the 'expansion tank' be able to overcome the head pressure from basement to floor above? This sounds quite doable for the average DIYer.

jzz30tt · #22 06-10-2010, 04:11 AM

Very doable for a DIY'er. Head pressure isn't going to factor the same way as a constant flow pumping situation since you'll be using a pressure tank to generate the pressure during flow.

The shur-flo pumps that i'm referring to are going to be similar to the pump that would be used in a small RV for water supply. They come with an internal pressure switch that will deactivate the pump at typical line pressure. Something along the lines of 40-70 psi.

The pump isn't able to supply the 1/2 inch line at the same flow as a house supply so we also tee in a small captive bladder pressure tank (1-2 gallon or enough to supply just more than one flush).

The toilet gets flushed and the pressurized storage from the tank supplies the replacement water for the back of the toilet tank. At the lowering of pressure the pump turns on refilling the pressure tank. Pressure builds back up to the set point of the pressure switch on the pump.

Toilet's are a good consumption point for this waste water since it will be high in mineral content and they aren't too finicky. Nor do they tend to suffer from mineral build up.

Enjoy!

jzz30tt · #23 06-10-2010, 04:18 AM

Oh and another tip for anyone using a RO or RO/DI system. Adding a booster pump to the feed of the unit will increase the efficiency and increase the product by a large degree. It can be a far more attractive option than spending the big bucks for a larger RO/DI system.

mike31154 · #24 06-10-2010, 04:21 AM

Thanks for the info, very helpful. I may be saying goodbye to lugging buckets next winter.

jzz30tt · #25 06-10-2010, 04:22 AM

No worries, glad to help.

mike31154 · #26 06-10-2010, 04:27 AM

Quote:

Originally Posted by jzz30tt

Oh and another tip for anyone using a RO or RO/DI system. Adding a booster pump to the feed of the unit will increase the efficiency and increase the product by a large degree. It can be a far more attractive option than spending the big bucks for a larger RO/DI system.

Good advice. Also a good idea to check your home plumbing for a PRV (pressure reducing valve). These are required by code in most areas with city water pressure to protect the home plumbing from pressure spikes. Should be installed fairly close to your main water shutoff or water meter. I believe the default setting is 50 psi, but this may be adjusted to a higher setting, so there's the potential for improving RO output without the requirement of a booster pump.

Gaffer · #27 06-10-2010, 02:16 PM

Nice. I really like some of the solutions you have.

I think for the time being I am going to use the 55gal rain barrel that I have in my basement to store the waste and then use a sump pump that I also have to feed either a rain barrel outside or a drip irrigation set up for my shrub beds in the front of my house.

We have probably 25+ small shrubs plus trees, ornamental grasses and annuals that can use some watering.

The current idea is to run 1/4" drip lines to the plants under the mulch and then put the sump pump on a timer to water them. Since the rainbarrel in the basement has a overflow near the top I will just put that into the drian in the basement for the time being.

We already have dual flush toilet as our house is certified Built Green already and I cant be bother to haul buckets up to manually flush the toilets.

I may also look into the hotwater option too.

Andrew

mike31154 · #28 06-10-2010, 04:01 PM

Quote:

Originally Posted by Gaffer

I may also look into the hotwater option too.

Andrew

Not sure about this, but the hot water option may only function properly if your system uses a conventional hot water tank. You mention a green home, so I suspect you may have a 'tankless' or on demand hot water heater? If so, I'd research that a little more before purchasing the 'hot water option'. Besides, that involves another bit of additional plumbing and possibly another booster pump, pressure switch, etc.

jzz30tt · #29 06-10-2010, 04:41 PM

Additionally you may want to consider the implications of running high mineral content water into a tankless water heater given the scaling issues. Same scaling would occur in a hot water tank but there is a larger margin for scale buildup before it becomes a problem in a hot water tank.

Gaffer · #30 06-10-2010, 05:31 PM

Sadly, I dont have a tankless system. They were too far along into the building process to put one in. I dont understand why they didnt put one in to begin with.

Now I am wondering if the higly mineralized RODI waste may be bad for the hotwater tank. Also, I prefer soft water for showering etc., so adding harder water may not be to my liking.

Flushing toilets on the other hand, I dont really care what the water is as long as it gets the job done.

Hmmmm...

Andrew