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coralfarmer84
07/19/2006, 05:55 PM
When your making RO/DI water on a brand new unit should wastewater always be running out the waste line even when your making good water. Mine is producing more waste water then good water. The waste valve is giving a steady stream and the pure water is a small stream I'd say just above a heavy drip maybe a lil stronger. Can anyone tell me if this is normal. Its a 100 gpd one and it feels like its making the right amount of water just wasting a lot more. thanks

BreadmanMike
07/19/2006, 05:57 PM
That is exactly how it is. The waste water will be 4x the good water, if not more.

coralfarmer84
07/19/2006, 06:01 PM
lol well thanks... just seems like a waste of water to me. I'm making 400 gallons and throwing away 1600 lol, guess the water company had some say so in the design of these things... thanks for the quick response.

AZDesertRat
07/19/2006, 06:10 PM
Thats how they are designed to work. The waste stream is continously flushing the contaminants away from the membrane so it does not solidify on the fabric.

MrZ
07/19/2006, 07:27 PM
You can capture the waste water and use it for watering plants and filling up your washing machine. Depends on how frugal you want to be.

Roland Jacques
07/19/2006, 07:42 PM
if your water pressure is very low you will have even more waste than your supose to. 4 gallons watse water to 1gallon clean water is normal. 40 psi is the very min pressure for a lot of membranes. a lot of people like it at 60 psi. my tap water is very very good so i keep my pressure at 100 psi.
at the higher pressures your loss some purity but you get much less waste water.

AZDesertRat
07/19/2006, 07:48 PM
Pressure does not affect the waste ratio nearly as much as temperature does. With temperature the viscosity of water changes and thats why the waste rate changes, pressure really has much less effect.

Roland Jacques
07/19/2006, 08:38 PM
mine changed a good bet with higher pressure. my overall watse went down 25% from 75 to 120 psi. i dont rember the number when i tested it at 50 Psi but it was even more change with the lower psi. i look for some other test results. i know that Jim filterguys posted also showed good changes with 25 psi increase.

im sure your right that temp has more effect. AZ what do you think the best temp to have your water at?

AZDesertRat
07/19/2006, 08:43 PM
Between 77 and 90 is what they are designed for but the colder the water the better rejection rateyou will see as the water is "thicker" at lower temperatures. The trade off is lower production rates though. Since you have high pressures that would offset the lower production rate you normally see with colder water.

Roland Jacques
07/19/2006, 08:51 PM
now this was dual membraine tests but the watse ratio saving should be the same.
Waste product ratio at 100 psi 1.25 : 1
Waste product ratio at 65 psi 1.62 : 1
Waste product ratio at 60 psi 1.75 : 1

TEST RESULTS 65 PSI ENTERING FIRST MEMBRANE

Two 75 GPD Filmtec membranes in series
One 75 GPD 600 mL flow restrictor
Aquatec 8800 Booster pump producing 96 psi
Tap water temp 64 degrees
Tap water TDS 59 ppm
TDS entering DI 2 ppm
DI water TDS 0
Production water 1 gallon 10:45 minutes
Waste water 6.5 quarts
Production water 5.58 GPH or 133.92 GPD
Waste water 9.07 GPH or 217.62 GPD


GALLONS OF WATER SAVED 318



TEST RESULTS 60 PSI ENTERING FIRST MEMBRANE

Two 75 GPD Filmtec membranes in series
One 75 GPD 600 mL flow restrictor
Aquatec 8800 Booster pump producing 96 psi
Tap water temp 64 degrees
Tap water TDS 59 ppm
TDS entering DI 2 ppm
DI water TDS 0
Production water 1 gallon 11:45 minutes
Waste water 7 quarts
Production water 5.11 GPH or 122.64 GPD
Waste water 8.94 GPH or 214.62 GPD

GALLONS OF WATER SAVED 276

Roland Jacques
07/19/2006, 08:54 PM
AZ any good sugestions on temp regulating to get that 85 degrees?

i was thinking a pipe warmer wrap but im not sure you can regulate that.

AZDesertRat
07/19/2006, 08:55 PM
Geez, with Atlanta water why even have an RO? You guys are soooo lucky to have tap water like that! You could almost get away with one of those Aquarium Pharm. Tap Water filters.

AZDesertRat
07/19/2006, 08:57 PM
You might look into heat tapes. I am not sure what the preset temp is on those as when you ask about them in Phoenix you get a blank stare! I bought several for work to put on control valve lines that were freezing several winters ago and had to order them in through Grainger since no one knew what the heck I was talking about.

Roland Jacques
07/19/2006, 09:01 PM
that not my tap may tapwater. my tap water has been is 34TDS for the past 2 months. you right di only is not a bad option if i did not use so much water.

Roland Jacques
07/19/2006, 09:04 PM
thanks AZ, ill look into that tape got the grainger book right here.

AZDesertRat
07/19/2006, 09:06 PM
Another option might be a heat tape with a Ranco or Johnson controller to turn it on and off if their preset temp is too high. Tape the sensor to the tubing or pipe along with the heat tape and insulate the whole thing.

baja_hammer2003
07/20/2006, 05:15 AM
has anyone tried using 3/8" tubing and fittings with a 8800 pump to see if this helps with production rates and less waste?

Roland Jacques
07/20/2006, 06:32 AM
<a href=showthread.php?s=&postid=7777418#post7777418 target=_blank>Originally posted</a> by baja_hammer2003
has anyone tried using 3/8" tubing and fittings with a 8800 pump to see if this helps with production rates and less waste?

3/8 hose wont have any benifit. unless your Ro uses more than 1200 at 100psi gallons per day or you have very low pressure. and flow upwards of 700 GPD. i use 3/8" going from my pressure regulator to my RO only because it has a higher pressure rating.

here aresome test results from www.thefilterguys.biz
Just tested the 1/4" tubing with a 1/4 x 1/8 fitting at 100psi and it produced 1/2 gallon of water in 33 seconds or 54.54 gallons per hour.

without fittings

Lets do 5 Feet of polyethelene hose first: Results are in GPM and assume a level open ended hose (no head, no orifice)

10 PSI = .88 GPM
20 PSI = 1.3 gpm
30 PSI = 1.63
40 PSI = 1.92
50 PSI = 2.17
60 PSI = 2.4
70 PSI = 2.62
80 PSI = 2.82
90 PSI = 3.0
100 PSI = 3.2


Lets do 10 Feet of hose
50 PSI = 1.47
60 PSI = 1.63
70 PSI = 1.78
80 PSI = 1.92
90 PSI = 2.05
100 PSI = 2.17

vanmo92
07/20/2006, 09:27 AM
I figuerd out that if you put a flow adjuster on the end of the waste water line and turn it down then you get much less waste water and the good water comes out a bit faster. It increases the TDS of the good water by 1 or 2 but making the waste less is the only way my dad would let me have the unit.

CSS Reef
07/20/2006, 10:12 AM
I purcahsed a Typhoon III from Walter at airwaterice. I posed the same question to him and he said to never restrict the waste water line by any means.........

coralfarmer84
07/20/2006, 06:55 PM
I'm using well water myself.... thanks to everyone who helped out so far, i learned a lot about this thing. I don't know my PSI but i do know that the unit is not running at what its rated. I'm filling a 300 gallon tank and my RO/DI is rated at 100 gpd and I'm only getting about 50 out of it and its brand new.... Must be my PSI.....

Roland Jacques
07/20/2006, 08:47 PM
get a pressure gauge $8 at lowes

fahz
07/20/2006, 11:16 PM
<a href=showthread.php?s=&postid=7782306#post7782306 target=_blank>Originally posted</a> by coralfarmer84
I'm using well water myself.... thanks to everyone who helped out so far, i learned a lot about this thing. I don't know my PSI but i do know that the unit is not running at what its rated. I'm filling a 300 gallon tank and my RO/DI is rated at 100 gpd and I'm only getting about 50 out of it and its brand new.... Must be my PSI.....

You will generally see most people with well water with a psi of 35-40. Most people with well water do best with a RO/DI booster pump.

Jim

coralfarmer84
07/21/2006, 03:53 PM
I'll have to look into one of those