What am I?

[sudsmaster]

Minority opinion...

Natural gas is mostly methane, which is lighter than air. So there shouldn't be a big problem piping it to the upper floors of a skyscraper. What else would people do with their trophy penthouse kitchens with commercial gas-fired ranges?

I know that is a liquid nitrogen container because I used to freeze things in the bio lab back in the 80's with nitrogen from one of those. Ran an automated device that would gradually meter liquid nitrogen from the tank into an insulated box to do controlled freezing (cryopreservation) of various tissues/cells contained in cute little plastic vials within. Also used the tank to fill smaller tanks that contained same vials in longer term storage.

I did a little googling and it seems that the liquid nitrogen is used to cool POWER cables so that they can become superconducting and carry more current per ounce of copper. The nitrogen is carried into the length of the cable - which of course must be well sealed and insulated, as the nitrogen will eventually heat up and lose liquid mass to vapor mass. So it must be replaced either contiuously or on a regular basis.

The mad scientists are busy trying to make superconducting power cables that work at room temp... but don't hold your breath.

I guess the cost of maintaining cold conditions with liquid nitrogen is cheaper than buying bigger power conductors and ripping up the most expensive real estate in the world to place them. Liquid nitrogen isn't cheap, and I imagine a fairly large amount of it is used daily to keep the electrons moving in Manhattan.

 

[dalangdon]

The utility I work for used to use liquid nitrogen at the receiving substation by my workplace, but they stopped back in the early 90's. The tanks are still there though.

It was/is a fascinating mechanism. The whole substation is, as it's been there since the 30's, and still has some original equipment. The control house is a great WPA-era structure with a bunch of weird stuff in the basement. While almost everything else, including the dams, have been largely automated, they still keep old-school operators at that place, mostly because of the steel mill.

I know that our downtown network system uses oil filled conduits as a means of cooling conductors, but that is far above my paygrade

 

[bobbyderegis]

Can you imagine seeing that cannister after 9/11 on the streets of Manhattan? Up until a few years ago that would have caused a major public panic. Personally, I thought it was Toggle's laughing gas container. That's really why he's so cheerful all the time.
Bobby in Boston

 

[tolivac]

Some power company transformers use a nitrogen tank or and argon tank to use its gas to displace any air or oxygen from inside the transformer-this is to prevent oxidation of the transformer oil-if the oil becomes oxidized-instead of being an insulator it becomes a conductor.At the voltage these transformers operate it could mean the failure of the transformer and whatever homes and businesses it supplies power too.As power transformrs heat and cool-oxygen can be drawn into them-the nitrogen forms a "blanket" on top
of the transformer oil to prevent the air from getting into it.The nitrogen may also fill the unused space in a transformers "conservetor" tank-where the oil goes when it expands from heating.Its the tank you see above the transformer case.Some of the transformers in the transmitters have this.But they don't have the nitrogen tanks-have dehydrator pellets that absorb moisture and oxygen instead.
Oh yes RF transmission lines from the transmitter to the antenna for AM,FM and TV may have these lines filled with nitrogen or dehydrated air to prevent moisture entry and arc overs.The gas is maintained at a positive pressure so containiments can't get into the line.Have forgotten how may nitrogen tanks I have gone thru at radioi and TV stations-and dehydrator cartridges I have reviatalized.

 

[mielabor]

Aha, I already suspected that it was not for cooling. I can see that the nitrogen isn't liquid anymore once it has entered the tube into the manhole, otherwise ice formation would be visible. However, it seems rather cumbersome to have these dewars in the streets. I have never seen this here and I think that they would be quickly vandalised. All the interesting things you can do with liquid nitrogen!

 

[mielabor]

Now I think of it: has it something to do with pest control?