Storage Tank Options

[NE WOOD BURNER]

If a new 275 gal (oil) tank was reinforced by welding 1" rods through tank I would think it would hold the psi neccesary for a pressurized system?

 

[tbuff]

What type of "pressurized system"

They are really not designed to be pressurized, so I wouldn't risk it. Maybe a used or new LP tank.

 

[NE WOOD BURNER]

I have seen 1/8 inch steel(thermal storage) tanks advertised with reinforcing in them. Oil tanks are 12 gage steel wouldn't be hard to reinforce.
Lp tanks are great. But certainly are hard to situate in many areas especially basements with bulkhead. 275 gallon tank is much easier to handle.
I would utilize for a closed thermal storage for wood boiler.

 

[Karl_northwind]

I certainly wouldn't use the rolled side style fuel oil tanks.

I would and have considered using a farm-style round tank for closed storage. maybe use one (or 2) of these: http://www.turnertanks.com/Horizontal.html stood on end.
put the drain bung on the top to vent air. depending on the pressure you need, you could certainly have zero pressure and do a euro-style open system with a water heater as your open expansion vessel. it all depends on your need for pressure and why you think you need pressure. unpressurized doesn't necessarily have to be the same thing as open. you'll still need to monitor your water chemistry like any system.
and as a bonus you could also do an instantaneous preheat coil in the 3" or 4" threaded fitting in these tanks.
http://www.boilersupplies.com/tankheaters/american.html

 

[bmblank]

I would not use any tank not originally designed as a pressure vessel for a closed system. Sure, it may only be 15 to 30 psi, but 15 psi equates to more than a ton of force on each square foot of area.

 

[Karl_northwind]

I would not use any tank not originally designed as a pressure vessel for a closed system. Sure, it may only be 15 to 30 psi, but 15 psi equates to more than a ton of force on each square foot of area.

Agreed,
Just to be clear, I am not advocating pressurizing a tank not designed to be pressurized, just using it as unpressurized storage, with a flatplate heat exchanger to pull heat off to a pressurized distribution system (if necessary)
karl

 

[NE WOOD BURNER]

euro-style open system

What is a Euro- Style open system?

 

[bmblank]

Agreed,
Just to be clear, I am not advocating pressurizing a tank not designed to be pressurized, just using it as unpressurized storage, with a flatplate heat exchanger to pull heat off to a pressurized distribution system (if necessary)
karl

In that case you'd be fine. I'm using a 1600ish gallon previously buried fuel storage tank (round) now buried again outside the basement wall. People will harp about steel corroding with the water and galvanics, but with thick enough walls it should last a while.

 

[maple1]

I would not use any tank not originally designed as a pressure vessel for a closed system. Sure, it may only be 15 to 30 psi, but 15 psi equates to more than a ton of force on each square foot of area.

Agreed 100 times over. Don't use an oil tank on a closed/pressurized system, it's a recipe for disaster.

 

[Karl_northwind]

What is a Euro- Style open system?

https://www.hearth.com/talk/threads...-high-up-does-it-need-to-be.39890/#post-39890

basically, the expansion tank is an open tank (water heater?) with a drain pipe. the tank is placed up high, typically higher than your highest radiator. I have a buddy with one in a 100 year old house, gravity boiler. he's been there 40 years, and never had a problem.

figure your normal expansion for the water volume and temp range, and then double that at least for the volume of the tank.
we have to do that for Non ASME boilers.
in this case, with a non-pressurized system, where you want to have separate expansion from the big tank, you'd have the expansion vessel probably sitting directly above the big tank, on a rack, or shelf not 30 feet up to get 15 PSI. 15 psi is 15 psi, whether it's gravity or compressed air delivering it.

 

[infinitymike]

In that case you'd be fine. I'm using a 1600ish gallon previously buried fuel storage tank (round) now buried again outside the basement wall. People will harp about steel corroding with the water and galvanics, but with thick enough walls it should last a while.

Was it used for oil or gasoline?

If you sprayed it, I wouldn't worry about the outside corroding.
Besides, look at how long steel oil tanks last buried.

 

[NE WOOD BURNER]

So going with the underground idea: Why wouldn't an underground propane tank work if it where well insulated?

 

[bmblank]

Exactly.
I'd imagine it was used for gasoline. Unsure though, we got it from a junkyard and had to weld an end on it. Outside was spray foamed. Its an open system, but i know with the heat cycling O2 content is very low on the inside.

 

[maple1]

So going with the underground idea: Why wouldn't an underground propane tank work if it where well insulated?

It likely would, with closed cell spray foam to keep the water away from it. It would be a bear to service though if it ever needed it - and I like being able to open the enclosure around my basement tanks a bit on those cold winter days when my basement is just a bit on the chilly side. Storage tanks make tremendously good radiators, if the heat is needed in the space where they're situated.

 

[bmblank]

I agree. It would be great... Until there is a problem. We put a manhole in mine. Hell,i could go swimming in 180° water if i felt so inclined.
I don't feel so inclined.

 

[infinitymike]

So going with the underground idea: Why wouldn't an underground propane tank work if it where well insulated?

My intentions (one day) is to cut my garage floor open (where I have the boiler) and create a mechanics pit. I will lower the tank into the well insulate pit.

I will create a removable insulation panel that will be covered by a removable steel grate.

 

[tmudd]

I like that idea infinitymike. I think the ideal set up would be underground(floating slab above insulated tanks for access. ) with additional storage capacity that could be utilized with the opening of a valve for those times when you were around to build a fire to either heat more space of create longer times between firings. I gues you woupld neepd separate expansion tanks for each tank.
TLM