Need a Thermal transfer heatsink design

[devblazer]

Hi all I have a storage tank that has super cold liquid methane dripping into it.  The tank itself is connected to a heatsink at the bottom, such that it transfers heat to the pooled methane and turns it back into natural gas.  The heatsink itself is separated by a layer of Tungsten metal, followed by a layer of wolframite airlock doors that can be opened to stop thermal transfer whenever needed, followed by another layer of tungsten metal, then the methane storage unit. 

The methane comes in at about -170 degrees Celsius.  The natural gas will eventually get pumped into generators and that extreme coldness will end up going to waste.  I want to use it to cool stuff down first, but I dont want to pump the natural gas all over the place to cool various things down.

This leaves me with the option of building a heatsink as I mentioned before and piping liquids and gasses through the heat sink for cooling.  If i combine this with a temperature sensor and the layer of airlock doors I mentioned earlier, I can control the temperature of the entire heatsink, provided whatever the heatsink is made out of has enough thermal transfer speed.

And this brings me to my question!

I am looking for ideas on what to make my heatsink out of (perhaps I should call it a thermal storage block?).

Polluted water has decent capacity, but freezes too easily (although that probably isnt a problem for this idea), but its thermal transfer speed is not very good.

Something else Iv'e been looking into is using solids.  Granite isnt half bad on the thermal capacity as far as the material goes, but granite tiles can only be built manually at 100kg and granites thermal transfer while better than the polluted water, is still a bit slow.  I have however alleviated this by interspersing temp shift plates in a 1 every 3x3 fashion.

Another thing I've started playing around with is using a checkerboard type thing with a combination of solids like granite or metals for faster thermal transfer and liquid tiles for thermal storage, again interspersing tempshift plates in a sparse checkerboard fashion.

Does any body have any ideas for a design and materials too use.  The conditions for success as I mentioned earlier:
It must have enough thermal transfer speed to be able to control the heatsinks temperature reliably (within a couple of degrees Celsius) and support the cooling of piped contents across it.
It must have as much thermal capacity for thermal storage as possible (average per tile obviously)

Out of all the stuff I've tried so far, the best result I've gotten seems to be from using petroleum as my heatsink.  It has an okayish thermal transfer speed (2.0) and its storage capacity per tile is 750kg @ 1.76

[The Flying Fox]

6 hours ago, devblazer said:

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Out of all the stuff I've tried so far, the best result I've gotten seems to be from using petroleum as my heatsink.  It has an okayish thermal transfer speed (2.0) and its storage capacity per tile is 750kg @ 1.76

 

I would agree that petroleum is probably your best bet.  For my Aqua-turner cooler, I built my cold tank with oil.  The bottom radiator has the coolant pipes from the tuner (Filled with pH2O) and the top radiator is for the water I'm cooling.  It's able to keep the tank at a fairly stable 1C without freezing the water in the pipes so far and it's been running for a while now.  I've been letting water out of it at 800G/s and there's plenty of spare cooling capacity.

 

The other option that I can think of that might work for what you're doing could be a diamond window tile radiator.  Diamond window tiles will certainly transfer heat about as fast as possible (While having better thermal capacity then any of the metals) but less capacity then most of the mineral tiles you could use.  The trouble with using solid tiles as the thermal tank is you can't easily stick sensors and valves within them, of course.

[clickrush]

I'd use a petroleum room but cover the backwall (completely) with diamond/iron tempshift plates just to get as much thermal mass into the room as possible and high conductivity overall. I don't think the checkerboard thing has any value here. By covering the wall you get more thermal stability.