How to recharge DI resin

I'm using the ratio from here: http://reefkeeping.com/issues/2008-09/nftt/index.php , 22 oz. (0 TDS) in a bottle, add 6 fl oz lye. Cap quickly and give it a quick shake. Then into a big bucket of cold water. Even when it's in the water I tip or spin the bottle, just can't shake it without splashing too much indoors. Keep alternating shaking and cooling until it doesn't warm up noticeably when shaken. By the time everything else is set up it's cold.

I'm using the Rooto 100% lye. Had opened a fresh 1 lb jar yesterday and the seal seemed intact. I like the 1 lb. jars because they get used up quickly.

Now that I have seen how the separation occurs when adding resin to fresh lye solution, and I have thought about it some more, it almost seems like the cation got exhausted (and heavy) too quickly if that makes sense. I poured the lye in very slowly. Think pouring it in fairly quickly would help fluidize the resin? Give the anion a chance to rise before the cation gets heavy? I know the laws of physics don't work differently at my house, there must be something I did differently, if only slightly.

If I am interpreting what I saw (a while ago) correctly, if the lye solution isn't strong enough, the anion floats just under the surface. Tiny gap (<1/4") above it and large gap before the cation. I didn't quite have enough lye but used the same volume of water. Yesterday I used the full amount, no gap above anion.
 
The directions in the article are for a single canister. I have let the resin sit in lye for a hour at no time does the anion sink. The anion should float right to the top of the lye solution. Stirring seems to separate the resin in the lye for me.
Make sure you are making the solution for two batches as mentioned above. I have used both 24 ounces of water and 22 ounces. I have had success with both.
 
I finished regenerating resin about 15 minutes ago. The picture below is from that process. The lye that I used is at the top of the page (Rooto brand). I mixed 24 ounces of RO/DI water and 6 ounces of lye. I put the water in the container then the lye, capped off the container and shook it until it was warm. I then put it in a 5 gallon container with cool water in it. The lye solution cooled pretty quickly then I shook it again, I continued this process until the lye solution would not get hot when I shook it. I placed two 10 inch containers of resin, seen behind the bottle, and placed them in the upside down soda bottle. Then I pored the lye solution in the soda bottle. I waited about 1 minute and a gap formed. I stirred the resin with a wood skewer and let the gap form again, the gap did not change, nor did the thickness of the cation and anion resins.

This is the result of the above process.

96845New_resin_process-med.JPG
 
Since I have collected a bunch of resin I thought I would revisit the separated resin system. The reason was, it seemed that the amount of cation seemed to be lesser in some of the stuff that I have collected. I know that I could have simply measured in more cation to the mixed resin but, what the heck I have been thinking of doing this again.
The first time I did this I could not get 0 tds when I ran the separate resins. Once I mixed the same resins the tds went right to 0. I still do not understand why.
My results surprised me. After the resins have been recharged and mixed I usually install one container and run the canister into the drain, until I see 0 tds. Then I install the second container and run it until it reads 0 tds. The tds never goes directly to 0 it slowly lowers to that point on each canister. The process takes me about 15 minutes for each canister. I think this is because some of the chemicals still remain on the resins after the rinsing and the lowering to 0 tds is were those chemicals are leaving the canisters. This has always left the question; if the resin was separated then the anion and cation would not contact each other or any of the residual chemicals, and this should give a better charge. This time I installed the cation canister first and let it run for 10 minutes and then installed the anion canister, the tds went right to 0. There was no delay at all. I let this run for 15 minutes, just to make sure.
My RO water is about 15 tds when running. The tds coming into the system is 500. I get about 2 months from the canisters before the tds rises above 0. I will post if the separated resins perform any better.
 
My main display used about 5 gallons a day, the frags use about 2 gallons a day and our 55 uses about 1 gallon a day. So safe to say, the system uses 240 over a 30 day period. I recharged at 2/4/08 and recharged again today. I guess that I got 51 days of service before the tds started to show 1. That means my RO/DI system made 408 gallons of water on my last regeneration. Sorry the last estimate was a bit off; I needed to look in my note book for my last regeneration.
 
I do not know why but the separate resin system just simply does not work for me. The earlier post was wrong. During an upgrade to my system I looked at the TDS probes and found a wire broken from the probe housing. This is why it was reading 0 TDS. As soon as I repaired the problem, the TDS was reading 8. I took the canisters down and mixed the resin and reinstalled. The TDS went right to 0. This does not make any sense to me anyone have an answer to this it would be helpful.
 
dngspot,
just out of curiosity, which resin did you have in the first canister when they were separate?
 
Should be cation, then anion.
But mixed resin will work better than separate resins, just harder to regenerate. As the water goes through the mixed bed resin it is essentially seeing cation and anion beads almost simultaneously. "In effect it is going through an almost infinite number of separate bed systems: cation/anion, cation/anion, cation/anion. The water is more thoroughly deionized as a result." - copied from a water treatment company blurb.
Running separate beds can be feasible if you have a cation - degassifier(which pulls carbon dioxide out if you have hard water)- anion - cation - anion. I'm trying to figure how to do that easily on my system as the water is very hard and scales up my RO membrane after 6-8 months. That or an antiscalant (that requires and injection pump.)
By the way, anion regenerated with warm (105d F.) sodium hydroxide (caustic) will do a better job of regenerating and removing silica from the resin.
 
hmm
do the kati-ani systems have multiple cation and anion canisters, and do they have degassers?
I have not read much bad about them so just curious.
 
During some of the recent reginerations I have found the 2 liter soda bottle used to separate the resin is on the small side. I looked around for a 3 liter bottle and found it in a Dollar General store. The valve that I use can take the large opening at the top of the 3 liter bottle and the smaller opening at the top of the 2 liter bottle. I bought the trans fill valve at O'Reilleys Auto Parts. Below is a pic of the valve. Remove the white piece from the valve to accept the large opening on the 3 liter bottle.

Fillspout1.JPG
 
Great thread Dngspot, I am off to search for my equipment and supplies. Thanks again for coming to ***C and giving us a great demonstation. Not sure shy RC keeps changing the KMA to * but you know where you and your lovely spouse were this weekend. :)

Does anyone have an idea how many gallons a given volume of DI resin will treat given an initial TDS of say 200? Our water is very expensive here in Lees Summit and it could possibly be cheaper to just regen enough DI monthly than to waste 4 gallons of water to every one used. Just curious if anyone has looked into this.
 
A mixed bed resin generally has a capacity for a total TDS of 10000. Therefore 10000/200 = 50 gallons of water per each 2.5" by 10" cartridge.
 
Thanks Russ, that is what I come up with. My number is 4849 ppm, so yes 5000 will work for what I need.

Thanks again
 
My wife and I had a great time. It is great drinking beer and talking to fish heads. Would do it again.
 
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