Watch a video of spallation here.

One of the more interesting talks and technologies at the GRC Annual Meeting was given by MIT Researcher Chad Augustine on Spallation Drilling using a hydrogen-oxygen (H²-O²) fuel source. Spallation is essentially catastrophic structural failure of rock when extreme heat is applied in a small area. As the rock heats, small pieces spring free of the face of the rock in micro explosions.

Spallation drilling consists of a torch placed in close physical proximity to the rock face, the application of extreme heat to a small surface area, and removal of the waste material produced by spallation. The trick to this is, how does one get a flame to burn in the presence of water (used to remove the waste material) in an extremely high pressure (250 bar) environment? Chad and team reproduced this environment in a test facility at Potter Drilling in Redwood City and discovered that not only was it possible to keep the flame active in the high pressure aqueous environment, but that temperatures necessary for spallation to occur (500C) were maintained.

This could be an important and cheaper alternative to rotary drilling. And, there are a bunch of holes to be drilled…

This entry was posted on Friday, October 5th, 2007 at 8:17 am and is filed under Geothermal.