To lubricate well drill bits, a special liquid lubricant is circulated down and back out the hole. Along with it comes ground up rock which has to be separated before the liquid coolant is recirculated back to the drill head. This is done by passing it through a screen separator.
The issue is that the particulate is wet, which means that some of the coolant goes out the waste stream. The coolant is expensive. If any and all of it can be recovered, it presents a considerable cost savings.
Bill Billeaud, an inventor, came up with a way to blow the wet grindings with a Model 110006 6″ Super Air Knife, against a separation screen to blow the coolant off and recover more of the coolant.
Here is a video of the concept http://vimeo.com/7649488