If I have a consistent metal tube of 200 degree water passing at all times, if I place a metal tube of nitrogen beside(touching) will the water get cooler? What would happen with the nitrogen?

Is the nitrogen gaseous nitrogen?

By touching, do you mean that the nitrogen tube is in contact with the water of the tube? Or the nitrogen tube is in contact with the water tube?

Thanks for helping me... the water would be in a metal tube flowing consistentilyand the nitrogen would be in a another metal tube... the goal is to cool down the hot water that flows through the tube, but I am not sure it can be done with nitrogen and it would be a lot of heat around the nitrogen tube also.. Thanks for all your help

Hm... you didn't reply to my queries =/

Well, if you want to cool the water down, maybe the best way is to pass the water in a bigger metal tube, run a smaller, coiled metal tube in the water tube in which flows nitrogen. The longer the tubes, the more efficient will be the cooling process. The smaller and more coiled the nitrogen tube, the more efficient the process will be.

Now for how long can I use the nitrogen? Does it evaporate? Stop cooling at some point? Sorry if I sound dumb, but just don't know anything about it..

So... you mean the nitrogen is liquid?

Why are you using nitrogen? Why not just use air - its cheaper. Gasses are relatively poor heat transfer agents. You are better off with a liquid - how about cold water? Are you thinking about liquid nitrogen? That would be way too cold. What in the world are you trying to do?

Yes liquid

Well I need something that will chill water "FAST", and the water it's always in rotation, so I am trying to find a way to chill the water while the water still moving from point A to Point B and back to point A.

Tubes are touching tubes

Evidently you have a piping system through which hot water is continually being CIRCULATED (not "Rotated"). You should run this pipe into a tank of chilled water where the contents of the pipe cool as the water flows. This is a "heat exchanger" You also can cool the pipe with air - this is how the radiator in your car maintains the temperature of the engine. The fins on the radiator increase the surface area and hence the rate of cooling.
This is more properly a chemical engineering question although a chemistry lab has many kinds of apparatus to cool a reaction. Many times I've run the water through a coil of copper tubing that is sitting in a big beaker of ice water, As time goes by you drain off some water and add more ice.

Thanks Dr. Bob, now lets say the radiator has nitrogen around the coils so it's cooled with nitrogen not air, can this work?

Yes, but if you really want the water to cool fast, the tube of cold nitrogen should be INTO the water, not touching the tube in which water flows, as this will barely cool down the water.

Have you ever seen a condenser?

The most efficient way, is always one tube in the other, not one tube touching the other tube.

Hence, you won't want the tube to nitrogen to touch the tube carrying water, but you want either:

The tube of nitrogen INTO the water tube or tank,
Or the tube of water INTO the liquid nitrogen.

Though the latter will be much more costly.

And something more to add, it can be dangerous to use liquid nitrogen, for the material making up the tube can be damaged quickly by the high thermal stresses.

Liquid nitrogen is SO cold it will be very difficult to use. I think you are more likely to freeze the water in the tube rather than merely cool it. Why not just use a bath of tap water. 200 oF is not very hot and is easy to cool back to room temperature. For rapid cooling you want to maximize the AREA of the hot and cold surfaces in contact with each other. Touching tubes have very little contact area (geometrically just a point or a line) so they are a poor choice. That's why you want one tube INSIDE another reservoir of liquid. Gasses are poor heating and cooling agents - they have little mass to work with. Nitrogen would have no advantage over air, it just isn't free.