Ro/di

[bad coffee]

I'm thinking about ordering a refilable cart from www.buckeyefieldsupply.com They're $18 and then 5 pounds of resin is $39. (three + changes in 5 pounds) so it's $10 or so a change. I wonder if we order a lot if we can get a super good deal.

Unresistable, I see you're from OH, and you know about RO/DI. Are you part of Buckeye? We have no problem here about saying so- you could even become a sponsor and get even more business!

BC

 

[jhale]

I think you meant a check valve, rather than a flow restrictor.

A flow restrictor reduces flow in the waste line after the RO housing.

I'm not sure, I thought a check valve stopped the water from back flowing, or at least tried to I wanted to use the water in the tank for my water changes and topoff needs, so I thought if I put a flow restrictor before the DI filter it would slow the speed of the water going through the DI and give it more contact time. Is this right?

 

[jhale]

I'm thinking about ordering a refilable cart from www.buckeyefieldsupply.com They're $18 and then 5 pounds of resin is $39. (three + changes in 5 pounds) so it's $10 or so a change. I wonder if we order a lot if we can get a super good deal.

Unresistable, I see you're from OH, and you know about RO/DI. Are you part of Buckeye? We have no problem here about saying so- you could even become a sponsor and get even more business!

BC

that looks good. I like the fact that their resin is nuclear grade, because I'm always needing to clean up after my pesky reactor melt downs. :shocked1:

 

[House of Laughter]

JH,

I think (limited knowledge) that the flow restrictor before the DI will only decrease the amt of water going into the DI and contact time will remain the same - restrictor after the DI will provide more contact time, yes, BUT will do the following accrding to House thoery (again limited knoweldge) 1) decrease your output of RO/DI and increase waste 2) slow the water through all membranes and decreasing efficiency and increase TDS reading.

My understanding is that you need to allow the water through the membranes naturally (or faster) otherwise they won't filter properly.

UB? Any thoughts?

House

 

[jhale]

JH,

I think (limited knowledge) that the flow restrictor before the DI will only decrease the amt of water going into the DI and contact time will remain the same - restrictor after the DI will provide more contact time, yes, BUT will do the following accrding to House thoery (again limited knoweldge) 1) decrease your output of RO/DI and increase waste 2) slow the water through all membranes and decreasing efficiency and increase TDS reading.

My understanding is that you need to allow the water through the membranes naturally (or faster) otherwise they won't filter properly.

UB? Any thoughts?

House

:scratchch

I just want my tds to be 0 for more than a couple of weeks without having to change to DI. how often does everyone change the DI resin?

 

[bad coffee]

every year or so. Just another benefit of a smaller tank!

I just checked my TDS and it's at 26! so it's time for new filters all around, and a new membrane. I found a 100gpd on ebay for $35 free shipping. I'm ordering one this week. I'm also going to start a group buy for filters.

B

 

[bad coffee]

Just found this:
http://cgi.ebay.com/Ionics-Aquamite...540747120QQcategoryZ36353QQrdZ1QQcmdZViewItem

 

[jhale]

Just found this:
http://cgi.ebay.com/Ionics-Aquamite...540747120QQcategoryZ36353QQrdZ1QQcmdZViewItem

that's hot, does anybody have a cab that can tow that around?

26 TDS holly cow! you might as well pee in your tank :bigeyes2:

 

[jhale]

BC i would get the 75gpd membrane is has a 98% regection rate vs the 90% the 100gpd has. that's the one I got.

 

[purelyh2o]

Hey its Bryan again

John I never got any response regarding the sponsorship.
Please give me a call at 1 888 620 8894 or you can go to my website and hit the live support icon top left and it will open a chat window to me.
www.purelyh2o.com
Thanks
Bryan

 

[jhale]

hey Bryan, sent you some pm.

 

[Unresistible Blue]

welcome to the board UB, good advice.

putting a valve before and after the RO membrane is pretty simple, just cut the tube and stick a valve in where ever you want.

I'm thinking of adding a DI canister to take the place of the current post filters I'm using. The only reason is to house more DI so I don't have to change it so often.
Does anyone have any preferences for DI canisters.
I'd like to get a taller 20" one and pack it with a ton of DI.

The 20-inch clear housings are a bit more pricey - but you'd spend less on a single 20" than on two 10-inchers.

 

[Unresistible Blue]

I'm thinking about ordering a refilable cart from www.buckeyefieldsupply.com They're $18 and then 5 pounds of resin is $39. (three + changes in 5 pounds) so it's $10 or so a change. I wonder if we order a lot if we can get a super good deal.

Unresistable, I see you're from OH, and you know about RO/DI. Are you part of Buckeye? We have no problem here about saying so- you could even become a sponsor and get even more business!

BC

Hi BC - I am indeed with Buckeye Field Supply. Not been on your board much - spent some time here this morning. Looks like a great board.

 

[Unresistible Blue]

I'm not sure, I thought a check valve stopped the water from back flowing, or at least tried to I wanted to use the water in the tank for my water changes and topoff needs, so I thought if I put a flow restrictor before the DI filter it would slow the speed of the water going through the DI and give it more contact time. Is this right?

That is right - conceivably you could plumb a system for this and put an adustable flow restrictor between your pressure tank and the DI housing - with some experimentation with your tds meter you could make sure you weren't over-supplying the resin.

 

[Unresistible Blue]

JH,

I think (limited knowledge) that the flow restrictor before the DI will only decrease the amt of water going into the DI and contact time will remain the same - restrictor after the DI will provide more contact time, yes, BUT will do the following accrding to House thoery (again limited knoweldge) 1) decrease your output of RO/DI and increase waste 2) slow the water through all membranes and decreasing efficiency and increase TDS reading.

My understanding is that you need to allow the water through the membranes naturally (or faster) otherwise they won't filter properly.

UB? Any thoughts?

House

Let's back up a bit - I guess I'm not clear on why we are trying to increase flow through the DI resin - the RO membrane is typically the weak link in the chain, and where we look first to increase production (rather than the DI). Has this conversation wound its way through increasing permeate flow?

 

[Unresistible Blue]

:scratchch

I just want my tds to be 0 for more than a couple of weeks without having to change to DI. how often does everyone change the DI resin?

How many gallons do you have in your system? Do you go through lots of DI water? As an example, with tap tds between 275-350, and a 100 gpd Filmtec membrane supplying enough water for a 275 gallon system, I get about 7-9 months out of a DI cartridge.

A few thoughts here:
1. use high quality resin
2. decrease the tds coming from your RO

 

[jhale]

How many gallons do you have in your system? Do you go through lots of DI water? As an example, with tap tds between 275-350, and a 100 gpd Filmtec membrane supplying enough water for a 275 gallon system, I get about 7-9 months out of a DI cartridge.

I have about 155 gallons total.
the tank evaporates about 3 gallons per day and I change about 40 gallons a month so I'm making 130 gallons a month.
I just changed to a 75gpd RO membrane and added a booster pump and permeate pump, along with other valves, auto flush etc. so the system is all new. I'll have to track it and see how it works now.
my tap water tds ranges from the low 50's to the low 70's

 

[alrha]

my tap is about 45 TDS, RO is about 6 TDS (before DI) and after DI is is between 0-1 TDS.

 

[jhale]

That is right - conceivably you could plumb a system for this and put an adustable flow restrictor between your pressure tank and the DI housing - with some experimentation with your tds meter you could make sure you weren't over-supplying the resin.

would a john guest ball valve do the trick? I could close it and watch the tds meter. when the tds hits 0 that would be the spot to leave it. or does it not work that way?

 

[Unresistible Blue]

I have about 155 gallons total.
the tank evaporates about 3 gallons per day and I change about 40 gallons a month so I'm making 130 gallons a month.
I just changed to a 75gpd RO membrane and added a booster pump and permeate pump, along with other valves, auto flush etc. so the system is all new. I'll have to track it and see how it works now.
my tap water tds ranges from the low 50's to the low 70's

Jhale - with a high rejection (98%) 75 gpd membrane, and tap water tds that low (you have great tap water), your post RO tds levels ought to be less than 2 ppm. You might want to think about using just RO.

If you choose to use DI as well, your resin ought to last for a very very long time.