EKO 40 1500 gallon Storage project

[Ryedale]

Ok Got the pics working.....I think.

I began working on the storage tank arrangement for my boiler.
This seems to be the most difficult and time consuming portion of the project. The fact that I'm not using a "prebuilt" or "off the shelf" storage tank makes for many hours of comtemplation and "engineering".

I bought a used bulk milk tank in March of 09, and with other projects continuing to bump the boiler on the priority list, I'm finally really focused on this.

The tank is Stainless Steel, and was once mounted on the back of a truck to go out to farms and pick up milk. I suspect it is from the 60's or early 70's as it had remnants of cork insulation.

OK... Stainless is Impervious to problems.....right???? thats what I thought when bought the tank, "it will never rust out like a carbon steel tank, should last forever" I was thinking....well.....
I work at a large pharmaceutical company, and have become aware of a problem that can destroy stainless steel systems, like tanks, pipes, pumps etc. It's called CUI, or Corrosion Under Insulation and SCC....Stress Corrosion Cracking. I've seen a few references to it here at Hearth.com This probem is intensified in hot and wet climates.
We have an example of a major macro failure on our site with this problem. It's about a $10,000,000 pipe system that feeds our chem buildings, the pipe is 4in stainless "tube" thinwall pipe all connected by tri-clover type dairy fittings. The pipe was installed as recently as 6 years ago, and has failed due to this corrosion.
The insulation is Polyisocyanurate (urethane type) and the jacketing leaked, allowing water to sit between the insulation and the bare stainless. This pipe runs constantly at 150 degrees F. It's actually is a loop, with a type of water called "Low endotoxin water" super purified, only one step away from becoming "water for injection" which can be litterally safely injected into people..like IV fluid etc. It's kept at this high temp to keep it pasteurized all the time.
This water leaking through the outer jacketing allowed it to sit in a hot, wet environment, creating halides, IE chlorine, coming out of the insulation and has turned the pipe to something like swiss cheese. it has spider cracking and it "weeps" water in hundreds of places, the only repair is to replace the pipe. The new installation will require a "coating" put on by painters before the new insulation is installed.
So... there went my idea of an inpervious stainless installation. Thus, the barrier between the tank and the insulation.

Due to the size of the tank, I need to put it in the pole barn, along with the EKO 40. I will have an insulated room 16'x16' and the "storage tank box" will be inside this room. Minimizing heat losses is one of my highest priorities.
so...
1 minimize heat loss
2 don't destroy the tank by accident, or poor engineering.

I have come up with a soloution to both and will post some pictures of the project as I go. Feel free to offer suggestions, as long as they aren't a "total abandonment" of my path go easy on me.

When I received the tank it had three carbon steel rings that originally served to mount the tank to the truck, I have removed them and cleaned the tar coating (under the original cork insulation) and basicly got the tank down to clean stainless.
Wall thickness is .100 in, or about 12 ga. I believe they helped to keep the shape of the tank, and in a "Moving" application with no baffles in the tank, it needed the strength. I am not using the carbon rings, and will let the tank sit in a saddle.

Due to the massive weight of the tank I have made a plywood bulkhead saddle arrangement, the tank will slip into this like a cartridge into a magazine. The tank will touch only clean spruce or pine, and care will be taken that when I spray the insulation (contractor will do actually) the backside of the wood slats will be sealed so no insulation can touch the stainless. My tank will be indoors, and shouldn't get wet, but hopefully "halides" won't form if i do barf the tank over somehow, and water gets into the insulation. It should be able to be dried also, I can just vent the outside of the tank until everything dries out again.

Here are some pics (hosted at photobucket) showing my progress so far.

original condition of tank.....icky!

Using Carbon steel ring to pattern the tank

Lining the frames with furring strips, added tremendous strength. My son was really bummed when I slid the tank in, no more "fort"

Lets get the whole family involved

Nice tight fit

Almost there......

 

[sparke]

The link works if you copy/paste the whole link. Anyway, nice carpentry job. Where are your pipe taps?

 

[joecool85]

STILL WORKING ON PICTURES, can I add more than one IMG link to Photobucket??

It's not working due to the space in "BOILER PROJECTS". This forum doesn't like spaces in the URL. If you change that on photobucket to something else you will be good. Use a dash or something instead of a space.

**edit**
Forgot to say, looks good so far. And I like the idea of keeping a small air gap around the tank. Should last forever the way you're doing it.

 

[ewdudley]

The link works if you copy/paste the whole link. Anyway, nice carpentry job. Where are your pipe taps?

(Paste the URL, then replace double spaces with a single space.)

 

[Ryedale]

STILL WORKING ON PICTURES, can I add more than one IMG link to Photobucket??

It's not working due to the space in "BOILER PROJECTS". This forum doesn't like spaces in the URL. If you change that on photobucket to something else you will be good. Use a dash or something instead of a space.

**edit**
Forgot to say, looks good so far. And I like the idea of keeping a small air gap around the tank. Should last forever the way you're doing it.

Thanks, it worked.
sorry for the delays.

 

[Ryedale]

The link works if you copy/paste the whole link. Anyway, nice carpentry job. Where are your pipe taps?

Pipe taps are going in the end with the drain port. There will be at least 4, and as many as 6 or 8 1" pipe couplers welded into the end.
I have a friend who is going to Tig them in. I have done some Tig welding, however with the tank metal being .100 thick, I wanted a "skilled" person doing this important step. Welding will probably happen in the next week or two. then onto heat exchangers.

 

[taxidermist]

Man it looks pretty cool! Where do you live?


Rob

 

[pybyr]

That's truly impressive!

 

[ewdudley]

The link works if you copy/paste the whole link. Anyway, nice carpentry job. Where are your pipe taps?

Pipe taps are going in the end with the drain port. There will be at least 4, and as many as 6 or 8 1" pipe couplers welded into the end.
I have a friend who is going to Tig them in. I have done some Tig welding, however with the tank metal being .100 thick, I wanted a "skilled" person doing this important step. Welding will probably happen in the next week or two. then onto heat exchangers.

Good answer!

What is the elevation of the pole barn relative to the rest of the system? It would be a shame to fool with heat exchangers if a vented expansion tank in the rafters could allow you to tie the system together without any heat exchangers.

--ewd

 

[Ryedale]

Man it looks pretty cool! Where do you live?


Rob

Thanks it was rewarding to get that much done. I imagined the tank not fitting, but it slipped in pretty close. I'm in the Kalamazoo area.

 

[Ryedale]

The link works if you copy/paste the whole link. Anyway, nice carpentry job. Where are your pipe taps?

Pipe taps are going in the end with the drain port. There will be at least 4, and as many as 6 or 8 1" pipe couplers welded into the end.
I have a friend who is going to Tig them in. I have done some Tig welding, however with the tank metal being .100 thick, I wanted a "skilled" person doing this important step. Welding will probably happen in the next week or two. then onto heat exchangers.

Good answer!

What is the elevation of the pole barn relative to the rest of the system? It would be a shame to fool with heat exchangers if a vented expansion tank in the rafters could allow you to tie the system together without any heat exchangers.

--ewd

Tank and EKO on same level, on the slab in the pole barn
Planning on running Central thermopex to the house, feeding domestic water side-arm, and 19x20" coil for the forced air furnace.
Top of the tank has a manhole access which would be very difficult to keep sealed in a closed system. Could probably circulate tank water to house, using pump in the basement, It would be flooded pump, not lose prime. I'm trying to avoid the 1500 gallons ever getting into the basement (Pipe failure etc, flood basement with 180 degree water while away. ) Open to ideas.

Andy

 

[dogwood]

Ingenious method of rolling the tank in too. I liked the upside down casters you had near the opening. I also like how nice and shiney you got the tank. Brought back fond memories of our own thousand gallon ammonia nurse tank sanded down before repainting. Great fit into the opening as well. You did some good measuring work there. How many hours did you put into the carpentry? Did you mention what you'll be insulating with? And from the pictures it appears you got your wife to do most of the heavy lifting pushing the tank into place, which is an equally impressive achievement on your part. I showed the last picture to my wife, as we have to move our tank six inches closer to the wall. Not to be outdone, she said she'd get right on it. Nice work in all regards.

Mike

 

[ewdudley]

Tank and EKO on same level, on the slab in the pole barn
Planning on running Central thermopex to the house, feeding domestic water side-arm, and 19x20" coil for the forced air furnace.
Top of the tank has a manhole access which would be very difficult to keep sealed in a closed system. Could probably circulate tank water to house, using pump in the basement, It would be flooded pump, not lose prime. I'm trying to avoid the 1500 gallons ever getting into the basement (Pipe failure etc, flood basement with 180 degree water while away. ) Open to ideas.

Andy

I was envisioning the manhole welded shut or bolted in place with a decent gasket, should hold for three psi I would think.

But I don't have an answer for the flood risk except to suggest that a stout piping and a reliable check valve at the tank where the house loop returns to the tank should eliminate any possibility of the tank draining into the house.

Then all you'd need is a 60 gallon open expansion tank six feet higher than any other component in the system and a 1.00" or larger boiler blow-off safety pipe that feeds into the top of the open expansion tank.

--ewd

 

[Donl]

Unbelievable! Do I see someone here that has built canoes in the past?

Don

 

[sdrobertson]

Man it looks pretty cool! Where do you live?


Rob

Thanks it was rewarding to get that much done. I imagined the tank not fitting, but it slipped in pretty close. I'm in the Kalamazoo area.

Beautiful work. One thing that I would warn you on is watch for condensation while filling the tank. You should be alright this time of year but if its warm in the building and you fill it with cold water it might want to start to really sweat. If you do get allot of water, just fire the boiler to heat it up to dry out all that wood before you insulate.

Hesperia Michigan here.

 

[joecool85]

Beautiful work. One thing that I would warn you on is watch for condensation while filling the tank. You should be alright this time of year but if its warm in the building and you fill it with cold water it might want to start to really sweat. If you do get allot of water, just fire the boiler to heat it up to dry out all that wood before you insulate.

Hesperia Michigan here.

Good point, and I agree.

 

[Ryedale]

Man it looks pretty cool! Where do you live?


Rob

Thanks it was rewarding to get that much done. I imagined the tank not fitting, but it slipped in pretty close. I'm in the Kalamazoo area.

Beautiful work. One thing that I would warn you on is watch for condensation while filling the tank. You should be alright this time of year but if its warm in the building and you fill it with cold water it might want to start to really sweat. If you do get allot of water, just fire the boiler to heat it up to dry out all that wood before you insulate.

Hesperia Michigan here.

Someone mentioned that to me. I think our ground water is about 50 to 55 degrees, so as long as it's colder than that when I fill I should be ok, I'll leave the "boiler room" open to the fresh air. Good point, I will have it insulated so it should have minimum air contact while filling but I appreciate the thoughts of the group.
Andy

 

[bigburner]

I have a large mass boiler that holds 1200 gal +/- . on the start up it sweats so bad you would swear it was leaking, I tried small fire, big fire, it just sweats. No way to measure it, but a guess is 20 gals. I also use open storage on part of my system. Nice job on the woodwork.

 

[Ryedale]

I have a large mass boiler that holds 1200 gal +/- . on the start up it sweats so bad you would swear it was leaking, I tried small fire, big fire, it just sweats. No way to measure it, but a guess is 20 gals. I also use open storage on part of my system. Nice job on the woodwork.

Guessing start up means filling the 1200 boiler tank with fresh cold water?? Do you empty and then fill each heating season?

 

[brad068]

Hey Ryedale,

Just reading your first post and see you have also seen ss failure in a unique situation. I too had an experience will some potent chemical called ferric chloride @ 38% conc. It sat in a 12 Ga. 316 ss pan for 3 days and ate holes right through it!

On a different note, your tank looks alot like mine. I left the foam insulation and outer shell on for added R value.

 

[Ryedale]

Hey Ryedale,

Just reading your first post and see you have also seen ss failure in a unique situation. I too had an experience will some potent chemical called ferric chloride @ 38% conc. It sat in a 12 Ga. 316 ss pan for 3 days and ate holes right through it!

On a different note, your tank looks alot like mine. I left the foam insulation and outer shell on for added R value.

I know we cannot always plan for every variable, after all we aren't going to the moon, but the more we see in our careers the more we can apply to our own equipment. Unfortunately it can stall our projects (I'm famous for this LOL)
Hydrochloric acid basically dissolves stainless, very quickly like you said the ferric chloride did, there has been more than one occasion where acids have been introduced to lines, pumps and tanks where I work and they are being replaced shortly after.....very expensive mistakes.

 

[bigburner]

"Guessing start up means filling the 1200 boiler tank with fresh cold water?? Do you empty and then fill each heating season? "

it's empty now. doing a re pipe on the return line. I wouldn't matter any way. the water has to be pretty warm before it doesn't sweat. In my case there is 300/400 feet of 3 inch heat exchanger that has to get up temp before the flue gas doesn't condensate and run out the ends. The shell isn't insulated and that will sweat also just not as bad. In your case I would finish the project and fire it up. The sweating in your case would only be from the dew point, if it's completely insulated and say a little air gets in there it might get damp but as soon as it gets warm it will dry out. I too have had a very bad experience with S.S. in large commercial ice making equipment, to the tune of 6k

 

[DaveBP]

Most people don't realize that "stainless steel" is a marketing term, not an engineering term. Salesmen don't repair the things they sell.

 

[in hot water]

Nice work on the support. Looks like you are the "go to" craftsman should we ever need an ark

What temperatures do you plan on running? My experience with radiant heat installation on plywood and other manufactured products is 140F max. Will the pine strips insulate higher temperatures away from the plywood so the adhesives stay intact? Maybe the air gap around the tank will provide some isolation.

 

[Ryedale]

Nice work on the support. Looks like you are the "go to" craftsman should we ever need an ark

What temperatures do you plan on running? My experience with radiant heat installation on plywood and other manufactured products is 140F max. Will the pine strips insulate higher temperatures away from the plywood so the adhesives stay intact? Maybe the air gap around the tank will provide some isolation.

Ahhh, you almost had me on this one.... I was suddenly a little puckered.
I bought my plywood on sale at Menards from their "premium" section about $29 per sheet, comparable with good treated and better cdx and bcx grades. Normally $32 or $34 a sheet I think.
when I looked into it I found it was Interior and Exterior grade, thinking it would hold up to direct moisture or liquid water very well. So no problem there, now the temp issue.
I just got off the phone with the manufacturer of the product (AraucoPly) and on the Structural Properties cut sheet.

It says.....
AraucoPly is glued with a WBP Phenolic Resin The glue line meets European EN 314 and US PS1-07 standards. TECO and PSI/PTL control in a continuous basis the quality of the glueline. Formaldehyde emmision is below E1 level.

Ok I looked up WBP Phenolic Resin. It stands for Weather and Boilproof Phenolic resin. This is similar to most marine grade plywoods, the type used in fabrication of wood boats. It has to pass a test where it literally is boiled for x hours in water, and cannot de-laminate.

so... I think I dodged a bullet.
The technician in Georgia, the importer/manufacturer is going to try to get me a cut sheet on the resin, but it sounds like I'm safe.