TOKYO - A nationwide effort to recover valuable resources is gaining momentum in Japan, where discarded personal computers are being transformed into a significant source of recycled gold.
At first glance, piles of discarded computer circuit boards appear to be nothing more than waste, but they are in fact a rich source of gold and other rare metals.
At a recycling company in Nagoya, partnerships have been established with 760 municipalities across Japan to promote resource reuse. The company operates a system that allows free collection of up to 20 kilograms of items, provided at least one personal computer is included, enabling it to gather around one million discarded units annually.
“These are from Saitama Prefecture, and those are from Shiga Prefecture,” a staff member said. “We collect from all over Japan, from Hokkaido to Okinawa.”
The primary targets are rare metals such as gold and palladium contained in electronic components. Discarded electronics rich in such materials are often referred to as “urban mines.”
After manual disassembly, circuit boards are efficiently collected and transported to a recycling plant in Kitakyushu.
Masakazu Konishi, group leader at Astec Irie, said: “These are circuit boards that arrived from Nagoya. The gold-colored parts can be processed to recover gold. What we have extracted is shown here.”
The process begins with removing components using specialized equipment, followed by sorting. A conveyor belt equipped with eight nozzles uses AI to identify hundreds of component types by color and shape, separating them with compressed air. Among these, connectors contain particularly high amounts of gold.
“We recover gold from parts that have gold plating,” Konishi said.
The selected materials are then immersed in a solution that dissolves impurities, and after about 12 hours, gold with a bright metallic sheen emerges.
“We have confirmed the purity to be over 90%,” Konishi added.
More than 10 grams of gold can be extracted from one ton of computer circuit boards—several dozen times the yield of natural gold ore. The recovered gold is then reintroduced into the market.
“Circuit boards contain many other metals beyond those we are currently recovering, and we aim to further develop technologies to extract them more efficiently,” Konishi said.
Urban mining, which turns electronic waste into a valuable domestic resource, is becoming an increasingly important initiative for Japan as nationwide efforts to recover materials continue to expand.
Source: TBS
