Building a tannin filter
I just joined the forum. I live in central MN. I have a shallow well that has 5 parts iron, 18 grains of hardness, PH - 7, and what has been described as "medium tannins" I have a Terminox brand Pyrolox filter that uses a chlorine injection system and a Fleet Farm water softener model FFE-1054-M. Specs are 24,600 - 33.400 grain capacity. Water out of the softener has been tested and measured 0 iron, and it is soft. We still have tinted water and get yellow stains on white laundry. I have sent a sample of my water to a lab for tannin analysis and should get results back any day. I am sure that I have tannins. the color does not settle out of the water. I have been doing research on tannin filters and I am going to try to build my own from an Econominder 2500 controller with a 9 x 48 tank that I picked up off Craig's list for $50. I figure the resin and brine tanks are worth more than that even if I have to buy a new controller. The valve and piston were rebuilt in 2002, and the softener was taken out of service in 2007. Like many things, the more I learn, the less I seem to know. I am strongly leaning toward Tanex brand resin because it is supposed to have success with a broad range of tannins. My plan at this time is to put 1 cf of Tanex in the tank all by itself and regenerate with it's own brine tank. I am in the process of cleaning out the resin tank. I removed the head and powered it up. I gave it a manual regeneration and the piston moved and the cam for the brine worked. that's as far as I have gotten. the BLFC sticker says 5 GPM, 1.5# salt per minute. This controller has a meter, but no settings for hardness or people. I don't think that will be a problem for my application, It looks like I can set it to regererate after a set number of gallons. I would like to understand more about the pins behind the timer, According to an article I read Generally, the resin will be brined at approximately 10 lbs per cubic foot salt (NaCl). I am not sure how to make the Econominder 2500 do this. Also, it stated that The anion should be backwashed at a flowrate of approximately two gpm/sf. Can I restrict the flow to achieve this rate?
Also, I was reading a thread here where Ditttohead had this reccomendation:
"Here is my recommendation, this is a very unique system designed specifically for your application.
Stage 1: Minimum, A 9x48 Iron and hydrogen removal system utilizing Pyrolox. Please note that your pump needs to be able to pump 11 GPM to properly backwash the Pyrolox.
Stage 2, an parallel tank system with softening resin in tank 1, and Tannin selective resin in tank 2. This unique design eliminates the need for seperate regeneration cycles for the softener and tannin systems. The softener regenerant wast (chloride) is used to regenerate the tannin resin.
This design requires the addition of a resup feeder to lower the pH of the brine water so as to prevent the precipitation of the caco3 in the anion resin bed."
This sounds like it might work for me. I just wonder how exactly the regeneration would work. mainly achieving the backflow rates listed above, and I am guessing that the brine rinse exit on the softener would be the entrance on the tannin filter, then down the drain? So how would I choose a pounds per cubic foot salt setting for the brine? Am I over thinking all this?
Any advice would be greatly appreciated!
The design I was referring to is typically only sold by companies that have a good working knowledge of the local water conditions. This picture shows the general design, a single valve regenerates two tanks with the same regenerant. it is a highly efficient design but does take some knowledge to do properly. my own system has 4 tanks regenerated by 1 control valve. The picture below shows the general design, for your application, the first tank under the valve would be water softening resin, the second tank would have your tannin selective resin. For that application, the second tank would be a nerrower tank so the backwash rates would match. you would calculate the capacity to the tank that would run out of capacity first and regenerate the system at that point. It is a great design, but has its limitations. A res-up feeder and occassional resin cleaning should be done for technical reasons. If your tank was a little larger, you could even add the tannin selective resin to the softener tank, but I am not a fan of this, too many problems.
If you do add the Tannin 2500 system to your current equipment, be sure it goes after the softener.
Thanks for the advice. I am leaning toward installing a separate system for the tannins using the 2500, which upon further research, turns out to have a 3210 Metered Timer Assembly. Are you familliar with these valves? I could use some help setting this thing up properly, in terms of setting the brine and backwash flow rate.
I am very familiar with the valve. It is an older valve, one of the originals. Open the timer cover and look near the micro-switches, there should be a white sticker with the manufacturing date on it. Also, attach a few pictures of the valve. Attachment 19028
The sticker reads 04/1992
It's newer than I thought!
The PO had paperwork from a rebuild in 2002. Seals, piston, and Brine injector assembly were replaced. He claims that he took it out of service in 2007 because of manganese issues. He replaced it with a Kinetico system. Would you replace the seals or try it first? How hard is it without a stuffer tool? Is there anything else I can do with it to bench test it?
I cleaned the old resin out of the tank. I was told that if I put 1cf of tannin resin in it I'll need to add a top distributor. I heard that I will have to somehow screw it in place. this has me confused. I have been looking at parts at softenerparts.com, it seems like a good place to get parts. I am trying to learn more about how softeners work, I'm still not sure about sizing injector nozzles, and they sell a 2.0 gpm Drain Line Flow Control ( DLFC ) Button. Is that what I need to get it to backwash at a flowrate of approximately two gpm/sf.?
I appologize for all the questions. If there is a tutorial or article that answers these questions, please point me to it!
Thanks again for your help and interest in my project!
Thanks for the help!