…on soil remediation!
Researchers have developed a prototype that cleans soil by making mud of it and blasting it with ultrasound:
Sound waves travel through water as a series of high pressure waves with low pressure areas in between. The low pressure causes the water to boil and form microscopic bubbles. The high pressure then forces the bubbles to collapse, generating a shockwave that produces localised temperature flashes of more than 4000°C and pressures of about 1000 atmospheres. That is more than enough to break down any complex molecules in the water, Sosa Pintos says.
Trials look to have been involving a “simplified” soil medium, so it’ll be interesting to see if the technique is as successful in the field.
(NewScientist: “Sound blaster cleans contaminated soil,” by Tom Simonite [Sept 6, 2006])