Using the "triple point of water" to produce ice -- How does that work?

[jeffinbath]

TL;DR

A video about the deepest gold mine in South Africa, showed that at 3 Km depth, it was vital to use water cooling throughout the extensive underground works.

The video stated that at the surface, water was de-aerated and ice was formed using the triple point of water principle. It even showed a little snow ski slope was made as a demonstration. Unfortunately the physics behind this was not explained. The ice was used to chill the substantial flow of water being recirculated per second into the mine.

 

[oz93666]

I think what they were doing was subjecting water to high vacum , this would first de gas the water and then cause it to boil , even at close to zero , boiling would continue to extract heat and form ice , triple point ocours at 0.006 atm.

 

[jeffinbath]

Yes, thanks, that sounds right.