Help fully understanding kalk reactors

[YankeeTankee]

Hello R2R! I'm new here

After watching the BRS videos and looking on R2R I am still a little confused on kalk reactors....

I thought the following was true.... The white kalk that collects at the bottom of reactors indicates a supersaturated solution, as more water moves through the reactor the white part at the bottom gets smaller as kalk is used up and the solution get closer to becoming only saturated. This supersaturation is why the effluent can remain saturated as new rodi water moves through the reactor (whereas if the solution started only saturated and not supersaturated, as effluent left and rodi entered, it would become unsaturated).


I thought in a saturated solution it's all in solution, no white stuff. Yet they recommend 1.5 tsp/gal which is less than the amount stated to created a saturated solution (I read 2 tsp/gal) and show videos of the reactor w the white stuff at bottom leading me to believe that the white stuff at the bottom does not indicate supersaturation, help lol

 

[YankeeTankee]

Maybe I should have put this in the chem section @Randy Holmes-Farley

 

[Mastiffsrule]

Hello,

If I understand the question, the water can only hold so much kalk or saturation. An example I use is my kalk stirrer. I fill it up with ro and put 1/2 a cup of kalk in. The water will soak up only so much of the powder. The remaining powder falls to the bottom of the stirrer to be mixed with fresh ro dosed by a doser or ATO. The fresh water will allow room for more kalk to be soaked up.

Hope that made sense

 

[Mastiffsrule]

Maybe I should have put this in the chem section @Randy Holmes-Farley

Sorry, I was almost done typing when you posted

 

[YankeeTankee]

Hello,

If I understand the question, the water can only hold so much kalk or saturation. An example I use is my kalk stirrer. I fill it up with ro and put 1/2 a cup of kalk in. The water will soak up only so much of the powder. The remaining powder falls to the bottom of the stirrer to be mixed with fresh ro dosed by a doser or ATO. The fresh water will allow room for more kalk to be soaked up.

Hope that made sense

Yes this is exactly what I thought too! BUT... here is what does not make sense to me...

All these people suggesting 1 or 1.5 tsp kalk/gal like brs. Then I see all these videos including brs that show the white build up. BUT I've read on a few sites that a kalk solution is not saturated until 2 tsp/gal so.... either we have something wrong in our assumption or one of these numbers is wrong (I swear I dbl checked) or I guess the most likely culprit is that in the videos they are not following the common advice out there including there own suggested amounts on their site. It just does not add up.

 

[YankeeTankee]

I just wanna say this one more way to make it clearer...

BRS says 1.5 tsp per gal in reactor. If kalk is not saturated until 2 tsp/gal, that 1.5 tsp/gal solution is not saturated! Yet in their and every video there is the while build up indicating supersaturation which would have meant you would need to have used over 2 tsp/gal

 

[ca1ore]

I don’t know much about the chemical process, but I’ve run my various kalk reactors all the same way and they’ve worked fine. Personally I prefer the stir bar reactors. Essentially I dump a cup or so of kalk powder (calcium hydroxide) into my reactor. Let it settle and as long as there’s some white slurry at the bottom I assume the clear water above is saturated. As the ATO pumps water through the reactor, the gently agitated white slurry gradually disappears. At that point I dump in another cup of kalk powder. There may be some residual white crud that persists in the bottom, so a periodic cleaning is wise.