Landmines continue to be a worldwide problem, with two to five million landmines laid every year and associated blast injuries exceeding 26,000 people annually. The problem is compounded by the slow rate of recovery: the clearance of these minefields is 10 times slower than the rate at which they are emplaced.

For instance, since the 1982 war between Argentina and the U.K., only 5,000 landmines out of the original 20,000 anti-personnel and 5,000 anti-tank landmines have been cleared in the Falkland Islands.

To address this situation, researchers from Imperial College London have developed a technology that reveals the presence of landmines in peat soils. The O-Revealer system is based on the controlled use of smoldering combustion — the low-temperature, flameless burning of porous fuels such as peat.

Schematic of how the O-Revealer could be applied so that the smoldering fire spreads over a peat minefield: (a) before reaching the landmines, and (b) after spreading over the landmines. Source: Imperial College LondonAn electric power source and a heating coil slowly heat the top layer of peat to 500 degrees Celsius (932 F), resulting in smoldering combustion. The researchers replicated two of the most common types of landmines in the lab — the Italian SB-33 (widely used in the Falklands) and the Serbian PROM-1 (used worldwide) — and buried them in peat as part of the tests. A fan was used to simulate wind conditions, which affect the intensity and direction of a smoldering fire, and the team demonstrated how they could partially unearth the buried landmines.

Next, the technology will be tested at a military test site, after which the team would like to trial the O-Revealer in the Falkland Islands, working with bomb disposal de-mining teams. They predict that the O-Revealer is around five years from being used in the field.

The technology is considered feasible for field application in peat minefields worldwide like Falkland Islands, Vietnam, Burma, Laos, Uganda, Zimbabwe and the former Yugoslavia.