To transform 4000 data centers, the United States will extract rare earths from used hard disks (5)

2. Why need to recycle hard disks

Recently, the U.S. government on the other side of the ocean has listed hard disks as strategic data storage devices and consumer electronic products for U.S. government’s data centers, as well as as regarded them as raw materials for rare earths which is needed for energy technology and an important part of coping with climate change. In addition to the actions of the U.S. government, technology giant Google is also secretly studying hard disk recycling technology.

In 2019, in a laboratory in the Google data center in Oklahoma, Google spent six weeks manually disassembling tens of thousands of old hard disks and extracting a 2-inch-long permanent magnet component from each of them. Although the permanent magnet is not the core component of the hard disk, but it controls a head arm, which is the key to enabling the device to read and write data.

In these six weeks, Google experimenters and scientists harvested 6,100 permanent magnets. Through comparison, they found that there was no difference between these permanent magnets and brand-new ones. Then these permanent magnets which had been taken down were transported to a hard disk manufacturing factory in Thailand, where they were put into a new hard disk, and finally redeployed to data centers around the world.

Although this is far cry from the approximately 22 million hard disks discarded from data centers in North America every year, Google's experiment shows that hard disk recycling is feasible. Before this, the old hard disks replaced in the data center (exchanged every three to five years) had only one fate—they were crushed by the machine (that’s because there is strict control over the data).