In Chile, Japan tests method to make depleted copper mines viable again

Kyodo

A Japanese government-backed body has begun to test a new copper extraction technology using sulfuric acid mixed with multiple species of bacteria at a mine on the outskirts of Copiapo, Chile, officials of the organization said Wednesday.

Japan Oil, Gas and Metals National Corp., known as JOGMEC, designed the two-year large-scale experiment to check if copper can be extracted on a commercially viable basis with the bacteria-dependent technology from ores with very low copper content, they said.

These species of bacteria, which naturally subsist on copper ores, facilitate their dissolution.

Taro Kamiya, chief researcher at JOGMEC, said, “As copper ores from areas surrounding Copiapo provide high iron content rates, the bacteria can be easily activated.

“This technology makes it possible to extract copper at more than double the speed that can be achieved if humans extract copper with sulfuric acid alone,” Kamiya said.