Storage Thermal Latent Tanks Failure
Storage Thermal Latent Tanks Failure
(OP)
Hi guys,
There is a total of 5 STL tanks in operation which are connected to chillers for district cooling. During the night when cooling usage is low, cool brine will be passed through the tanks to freeze up the ice balls inside to store the latent heat. During the day, the ice balls will be melted to support the chiller.
The tanks were put into commission since 1993. Recently we found leaks on two of the tanks. We then proceeded to remove the insulation and realised that there were cracks together with warping/buckling on the wall of the tanks.
As there is a substantial amount of condensation occurring, we first thought that it might be due to corrosion that leads to lost in material. After we did a thickness testing, the reduction in thickness of the tank wall was not significant.
I could not figure out what could have caused this failure. Someone please enlighten me.
Many Thanks!!
There is a total of 5 STL tanks in operation which are connected to chillers for district cooling. During the night when cooling usage is low, cool brine will be passed through the tanks to freeze up the ice balls inside to store the latent heat. During the day, the ice balls will be melted to support the chiller.
The tanks were put into commission since 1993. Recently we found leaks on two of the tanks. We then proceeded to remove the insulation and realised that there were cracks together with warping/buckling on the wall of the tanks.
As there is a substantial amount of condensation occurring, we first thought that it might be due to corrosion that leads to lost in material. After we did a thickness testing, the reduction in thickness of the tank wall was not significant.
I could not figure out what could have caused this failure. Someone please enlighten me.
Many Thanks!!





RE: Storage Thermal Latent Tanks Failure
Some photographs might help.
Mike Halloran
Pembroke Pines, FL, USA
RE: Storage Thermal Latent Tanks Failure
Well..., I think that crack over there is one of these kinds and that crack over here is one of those kinds of crack. They are obviously not the same, one goes up and the other goes down. What else do you need to know? Oh..., maybe some photos and a few sketches of the tanks, with realistic proportions, details of tank construction and welding, piping, stl. matr’l. specs., etc., etc., with dimensions and the like. How do the brine pipes go through the tank wall and can freezing start right inside the tank wall? Do the tanks (fluid/water) freeze solid, or what size and shape do the ice balls/cylinders grow to? Freezing ice can exert very large forces on the tanks or pipes. What about the relative expansion and contraction of the various parts and the ice, how do they push on the tanks? How does the expanding ice push on the tank, how much movement, what type of buckling does this cause? Are the tanks open to the atmosphere? What do various details look like, in terms of hard spots, inflexible details and corners, where some tank wall movement causes high stresses and cracking. Is insulation closed cell insulation, so condensation is less likely to penetrate to the steel tank skin? Is there any consistency in crack locations and patterns, w.r.t. tank and pipe details? Rather than freezing solid ice, should the fluid be stirred so the whole volume gets to 32.1̊F and then the brine flow slows down, and holds the temp? Have you spoken with the engineers who designed the original system? My goodness, you ask a question like your OP, and then provide so little needed info. for a meaningful discussion, what kinda answers do you expect, except a bunch of questions?
RE: Storage Thermal Latent Tanks Failure
There are plenty of people here who can offer opinions, but need much more data than you have given up so far.
My motto: Learn something new every day
Also: There's usually a good reason why everyone does it that way
RE: Storage Thermal Latent Tanks Failure
RE: Storage Thermal Latent Tanks Failure