Incomplete Backflush or Rinsing

**ksnakes** · 02-08-2011, 09:13 AM

Thank you for any advice.

3ppm Iron, 25 hardness, ~~7.1 ph, medium tannins, medium sulfur smell, medium methane.

I have a chemical pump (chlorine/soda ash), Terminox Iron Filter and a mixed bed softener. All works well except imediately after a resin regeneration. I basically have a lot of unflushed or unrinsed muck coming through. The water is soft but what is coming through should have already gone down the drain. I have to open all cold water faucets for 5-10 minutes in order for this to clear. Then all is well.

My dealer had me increase both backflush and rinse cycles (twice) on the Autotrol head, but this does not help. I have yet to open my tank to inspect for any abnormalties.

Thank you and sorry if this is covered elsewhere.

**Akpsdvan** · 02-08-2011, 09:44 AM

What kind of increases did they have you do to the backflush and rinse cycle?
How many minutes to each?
I know that the older Autotrol's did not have a way of increasing the time for the backflush or rinse.. all that you could change was the brine refill time.

**ksnakes** · 02-08-2011, 10:53 AM

This is a newer Autotrol, don't remember the modle; but it is programmable. I don't remember, either, the increase in minutes but it was significant.
BTW, I used to have iron bacteria issue untill I installed the chlorine injection. Am wondering if there could be an issue with the resin screen inside the tank.

**JKERN** · 02-08-2011, 02:36 PM

That is something you might want to look at if you have an upper basket and the unit is a couple years old. It may have considerable build up, if it does clean it thouroughly and then run it through a cycle and see what it does. Also do you have the units plummed just as you wrote the pump, the iron filter and then the mixed bed softener? Also what is exactly the type of mixed bed you have?

**ksnakes** · 02-08-2011, 05:39 PM

Yes, it is plumed in that order; chem injector, pyrolox, softener. The system is a year old. And the mixed bed is Cation and Anion resins; 50/50.

**Akpsdvan** · 02-08-2011, 07:44 PM

Originally Posted by ksnakes

This is a newer Autotrol, don't remember the modle; but it is programmable. I don't remember, either, the increase in minutes but it was significant.
BTW, I used to have iron bacteria issue untill I installed the chlorine injection. Am wondering if there could be an issue with the resin screen inside the tank.

If there is an upper basket ,, then yes there could be a challenge with it.. if you can I would remove it, might have to slow down the back wash from say 5gpm to 4 or 3gpm so that the media does not leave the tank..

**LLigetfa** · 02-08-2011, 09:39 PM

Is not the final fast rinse and pack in the forward direction? The top basket should not be an issue then.

**Akpsdvan** · 02-08-2011, 10:02 PM

But if the upper basket is blocking the resin from moving as free as it should and the so called trash from getting thrown out in the backwash.. then yes the upper screen/basket will be a challenge.

**Gary Slusser** · 02-09-2011, 07:30 AM

You can not treat methane with chlorine etc..

Chlorine and methane don't play well together and are thought to be carcinogenic in combination.

You depressurize and aerate the water and then vent the methane to atmosphere in a way to get it away from people, sparks, flames etc. etc..

I see no need for soda ash, why are you using it?

Your equipment should not be getting rid of any methane.

Why are you concentrating on the softener and not the Pyrolox/Terminox filter?

Why is the chlorine left in the water instead of being removed with carbon?

Did you buy the system from betterwater.com?

**JKERN** · 02-09-2011, 07:44 AM

Well like Gary said first you might want to consider is getting rid of the methane and then treating the rest of your problems. Remember when using an atmospheric tank and aeration system you must always use an explosion proof rated air vent when dealing with methane. The other reason I had asked about the layout of the system is that with mixed bed softener systems it is typical to use tham as a polisher not as the main softener this muck you speak off is probably the result of the way you have your system installed also there is a large amount of issues when chlorinating into an iron filter and then into a mixed bed without removing the chlorine. Another qeustion I have is what kind of flow rates do you have and what pressure, whenever you use multiple tanks in sequence flow and pressure become more and more an issue.

**ksnakes** · 02-09-2011, 09:22 AM

I understand that methane is not being treated and that the only way to do this is with a aeration tank. This tank and additional pump is quite expensive compared to a nuisance gas at the tap. I simply included this fualt in my water profile (for sympathy

).

I treat with chlorine to kill iron bacteria and to assist the pryrolox with sulfer and iron removal and possibly some tannins. The iron bacteria would surely clog up the iron filter and the softener. I only inject enough chlorine to does these tasks. The pyrolox should enjoy a minor amount of "free" chlorine and I test to ensure that little if any comes past it. Any more than a little would not bode well for the resin.

I understand your concern about chlorine and methane forming trihalomethanes. The water we drink is from a RO with a carbon block. I understand this to be enough, let me know if you feel differently.

Lastly and interestingly, Gary S., you ask why I am not looking at the Terminox as the possible reason for this effulent being present right after a regenerationl. I suppose it is posible that the effulent could be coming from the iron filter and is present at the tap until the resin bed is sufficiently repacked and begins to behave as a mechanical filter. I have a sample tap after the iron filter, but have not noticed an issue here. I will check again, though.

JKern, I use a mixed bed because i was told this would be sufficent. In hind site, and after much reading, I realize that cation tank into a anion tank would have be more effiecient and long lasting. BTW. My flow rate going into my Terminox is 9 gpm. This is supposedly plenty of flow in oder to back wash the heavy pyrolox media and still have enough leftover for lifting the resin. I can see with a flashlight that during backflush of the pyrolox, it is lifted 10" and close to the neck of the tank.

Thanks

**Gary Slusser** · 02-09-2011, 09:46 AM

Methane can be dangerous and should be treated properly. The carcinogen part probably is not trihalomethanes; I don't know what it creates but it is said to be carcinogenic and thereby you should not chlorinate with methane present..

To kill any IRB you would first need to dose sufficient chlorine to oxidize all the 3 ppm of iron, all the H2S gas and any manganese present. And if you do that, you don't need the Pyrolox/Terminox filter and could swap it into a carbon filter to remove the 'dirt' caused by the iron etc. being oxidized and then remove the chlorine.

You didn't mention the reason for the soda ash...

Your filter and softener are set up to regenerate and backwash at different times with the filter to be done first and finished say 30 minutes before the softener starts right?

Also, they way you are doing things now with a bit of chlorine, and not killing any IRB to speak of, loads up the Pyrolox with dirt and bacteria it doesn't need. So suspect the Pyrolox to be loaded up and probably the cause of your current problem. Although better water wouldn't admit it, they are into selling stuff more than solving problem water problems.

**ksnakes** · 02-10-2011, 07:37 PM

Gary S, I have a response but need to find time to inspect inside the resin tank and see what there is as far as an obstruction or loaded up resin. I don't believe the pyrolox (iron filter) is the issue. This unit back flushes every night (14 mins), and yes before the resin tank (every 4 days). I will be very reluctant to inspect the inside the pyrolox filter tank. The risk is dislodgeing the tube from the bottom of the tank and being not able to return it through the heavy medium.

**LLigetfa** · 02-10-2011, 09:53 PM

Originally Posted by ksnakes

I don't believe the pyrolox (iron filter) is the issue. This unit back flushes every night...

I don't think it is best practice to backwash an iron filter every day unless there is so much iron that it is impeding flow. The iron trapped in the pumicite acts as filter media, improving the filtration.

That said, frequent backwashing can allow more iron to pass through the iron filter and contaminate the resin bed in the softener.

**Gary Slusser** · 02-11-2011, 10:08 AM

You're talking mechanical filtration where dirt buildup increases the filtering being done but that is a turbidity filter, not an iron filter.

Iron filter minerals should not be used for turbidity removal and the only one that will work some is Birm. And it can not be used with H2S in the water.

An iron filter oxidizes ferrous clear water soluble iron into ferric iron/rust particles then traps those particles and periodically backwashes them out to drain. An iron filter needing daily backwashing is seriously undersized and won't normally do a good job but backwashing daily will not prevent an iron filter from oxidizing iron and other things in the water like H2S and manganese.