Something to keep an eye out for …

[JoyfulNoise]

A procedure for removal of cyanuric acid in swimming pools using a cell-free thermostable cyanuric acid hydrolase

Abstract. Cyanuric acid (CYA) is used commercially for maintaining active chlorine to inactivate microbial and viral pathogens in swimming pools and hot tu

academic.oup.com

This article was published last November. The authors are affiliated with KIK Industries. KIK is a Canadian firm that basically is one of largest manufacturers of industrial chlorine products in North America. They manufacture liquid bleach for just about every non-Clorox branded bleach sold by various big box and grocery stores.

Basic gist of the article is that they isolated one of the enzymes that bacteria use when converting CYA into energy which, under certain conditions, can result in the formation of ammonia. However, the enzyme isolated in this paper converts CYA to a compound called biuret which can then be oxidized by chlorine into N2O and CO2. The catch is the enzyme works best when the FC is zero (because hypochlorite inactivates the enzyme). So, if it ever gets commercialized, it could be sold to consumers as a method of CYA reduction.

Something to watch.

 

[kul]

Thanks for sharing. That would be an interesting development. High Cya is tough to deal with and since drain or RO are the only options it would be nice to have something else that can accomplish the task. Now if there was only something similar for high CH! I look forward to learning what comes from this, if anything.

 

[Mdragger88]

I will try to forgive them for accidentally implying in the 2nd paragraph that adding cya to your pool adds chlorine & not elaborating/re-stating that the culprit is stabilized chlorine products.

So I guess the procedure could be similar to AA treatment wherein you would want to add polyquat 60 before allowing fc to drop to zero & do so in colder water if possible to prevent an algae issue? They made no mention of algeacide in the article so I would be interested to see if it conflicts with the other chemicals.
This is very interesting and promising especially for those in water restricted areas. I am curious to see the cost if/when this product comes to market- surely it won’t be as expensive or as hard to come by as reverse osmosis.

 

[an1vrsy]

Boy that article is so far over my head as just a retired guy with a pool who found TFP. I manage my CYA through the methodology that TFP utilizes. So you brainiacs go right ahead but it looked like greek to me. Oh, btw, I don't know algebra either, so you know high level non pool chemistry is over my head.

edit: I just noticed this was in the deep end. oops...

 

[Newdude]

However, the enzyme isolated in this paper converts CYA to a compound called biuret which can then be oxidized by chlorine into N2O and CO2. The catch is the enzyme works best when the FC is zero (because hypochlorite inactivates the enzyme).

Isn't this the same as the previous CYA reducers ? The ones that did work for maybe 10% of users but the other 90% got no reduction and algae from running no FC ?
It sure sounds very familiar, even if they are using a different enzyme or whatevs. Either way, a renewed mention/article would start a new round of questions for those looking for an easy fix.

 

[JoyfulNoise]

Isn't this the same as the previous CYA reducers ? The ones that did work for maybe 10% of users but the other 90% got no reduction and algae from running no FC ?
It sure sounds very familiar, even if they are using a different enzyme or whatevs. Either way, a renewed mention/article would start a new round of questions for those looking for an easy fix.

Those CYA reducers were based on the same chemistry BUT they attempted to use bacterial spores to inoculate a pool and then have the bacteria proliferate and do the work. The problem is that bacteria are exquisitely sensitive to UV light, chlorine and pH AND packaging up bacterial spores and hoping they survive is a huge gamble. My theory as to why those products failed is that there was no quality control on the product or how it was shipped and so customers basically bought bags of dead cultures.

The materials presented in that paper get rid of the biological part and just looks at the actual enzymes used. And you can see from the data that there is significant CYA reduction when no FC is present. So it has potential but still could suffer the same fate of the enzymes are not properly stabilized and/or packaged to protect them. Enzymes are complex protein structures that can easily be damaged by heat and mishandling so it remains to be seen if the lab experiment can be translated into a product for general use.

This is why I’m typically against the use of “enzyme” cleaners in hot tub products … they rarely survive the manufacturing process and thus lose a lot of their potency.

 

[Newdude]

Those CYA reducers were based on the same chemistry

Still with ya

BUT they attempted *whole lotta Greek*

So it has potential but still could suffer the same fate

Back with ya

 

[ajw22]

Enzymes are complex protein structures that can easily be damaged by heat and mishandling so it remains to be seen if the lab experiment can be translated into a product for general use.

There lies the problem.

I am not holding my breath.

 

[JoyfulNoise]

There lies the problem.

I am not holding my breath.

Agreed. That’s why I posted it in the Deep End so that if it comes up in a discussion there’s a record of it.

 

[Flying Tivo]

To the extend of my knowledge, look very promising! Both types of CAH-PR and -BD are very stable up to 50ºC. I also believe that if there is not a very detail process on how to use it, it will follow the others down the drain. Remember DPD has limited resolution, and due to this limitation, the pool would have to be treated as if there was still some FC available. The majority of pool owners still use guesstrips, we are the lesser ones.

My big question to @JoyfulNoise is: If FC is 0 with a CYA of 100, when PR or BD goes to work, what would happen to the bonded part of Cl-CYA? Would it become FC and break the enzyme and render it useless? Would that define the Ratio of CYA:Enzyme?

I would definetly look into some stock from Minnepura Tech!

 

[mgtfp]

If FC is 0 with a CYA of 100, when PR or BD goes to work, what would happen to the bonded part of Cl-CYA?

Short answer: No FC, no Cl-CYA.

Long answer:

You can't have FC=0 and still have chlorinated cyanurates. The reaction between FC and Cl-CYA is an equilibrium reaction. The reaction is constantly going in both directions.

In equilibrium, both reactions have the the same rate, so that there is no net effect happening, concentrations on both sides remain on a macroscopic time scale constant. As soon as you start removing FC, the reaction going "to the left" will be faster then the reaction going "to the right", as the rates are proportional to the concentrations. Until enough chlorine has been "released" so that the reactions in both directions have the same rates again. I.e. the system reached equilibrium again.

EDIT: I was was a bit sloppy in my usage of the terms FC and Cl-CYA, hope the principle came across.

 

[Flying Tivo]

Very clear, thanks!

 

[Katodude]

Ah, just bring your water over to my house. My pool eats CYA. I should culture my water and sell it. No ammonia by products either.

 

[mgtfp]

Ah, just bring your water over to my house. My pool eats CYA. I should culture my water and sell it. No ammonia by products either.

Do you offer international shipping?

 

[V___25]

Ah, just bring your water over to my house. My pool eats CYA. I should culture my water and sell it. No ammonia by products either.

I will buy your water! My pool is the opposite and holds CYA like no one's business.

 

[Casual]

My pool drops CYA to zero every winter. Have to add it / start from scratch again every time I open the pool. Guess I don't need to worry about reducing it.

 

[V___25]

My pool drops CYA to zero every winter. Have to add it / start from scratch again every time I open the pool. Guess I don't need to worry about reducing it.

Jealous.

 

[Newdude]

Jealous.

A mesh cover or no cover gives most of us in the Northeast between 1/2 and 2/3 free water exchange each year

 

[V___25]

A mesh cover or no cover gives most of us in the Northeast between 1/2 and 2/3 free water exchange each year

I have a mesh coverage and drained the water down below the returns at closing and my CYA is still like 50. Better than 200, but still.

 

[AUSpool]

I’m sure it’s been done before. Back when I had spare time I went through the patents for one of he CYA reducers and although I cant recall how they thought their product worked it was clear the manufacturing process for it was isolating bacterial enzymes. As I recall those that tried it didn’t have much luck.