"Urban Mine" -- an important technology to realize resource recycling

Unlike plastic, whose value lies in its fragile "molecular structure," metal's value lies in its indestructible "element itself," so horizontal recycling is desirable. But for now, horizontal recycling is limited to copper and some precious metals. This is because when recycled, smelting can be profitable even if the metal concentration is relatively low. If gold is enriched to 10ppm at the recycling plant, copper to a few percent, and tantalum to 20 to 30 percent, the remaining metal can be manufactured at the smelter for horizontal recycling.

Many other metals cannot be recovered horizontally if they do not reach a higher concentration, and many are recycled in cascades. Although the practice of using high-priced tantalum and other materials as roadbed materials helps reduce waste (landfill disposal), it is not an effective recycling.

Therefore, in order to strategically expand the horizontal recycling of metals, the Institute is conducting a study called "Strategic Urban Mine."

5 Measures to implement resource cycling

In 2013, IIDR established the Strategic Urban mining REsearch base SURE (Strategic Urban mining REsearch base), which brings together researchers related to resource recycling across sectors. It is committed to improving recycling technology, smelting technology for metal recovery, product design to promote resource recycling, and waste volume prediction technology.

Resource recycling requires the cooperation of enterprises. As a result, the SURE Alliance, whose members include private companies, industry groups, local governments and government agencies, was established in 2014 to increase the recycling rate of metal resources, expand the urban mine market, and realize the localization of Japan's recycling equipment industry and recycling plants.

The Separation Technology Development Center (CEDEST) was established in 2018 as one of SURE's initiatives. It acts as a research and development base for national projects and is currently developing equipment for the world's first automated/autonomous recycling plant. In addition to developing individual devices independently with participating companies, an integrated system-wide unmanned sorting system is being developed. The goal is to disassemble and sort waste 10 times faster than traditional labor, and to sort used parts with a separation efficiency of 80% or more.

Inside the factory

A system is being developed that can identify and disassemble more than 2,000 models of smartphones, digital cameras, camcorders and tablets, safely remove batteries and extract rare metals from circuit boards, and a demonstration plant is planned to be built in 2023.

In order to achieve resource recycling, it is also necessary to create a market for recycling equipment. Because most of Japan's resource recycling enterprises are small and medium-sized enterprises, equipment investment is limited. Therefore, it is not only necessary to broaden the understanding of the equipment, but also to broaden the understanding of the structure of the equipment.

In addition, on the premise of prioritizing the upgrading of domestic resource recycling in Japan, the global development of Japanese recycling equipment will also be considered in the future. It would be even better if recycling plants could be exported to Asian countries. It is important to prove that by introducing advanced recycling technologies, if there is an increase in high-quality renewable resources that can be utilized locally, then Japanese plants in the region can utilize them, which will also benefit the importing countries.

There is an urgent need to create technologies and mechanisms for recycling resources that are rooted in Japanese industries, rather than copying European technologies. In order to build a resource-recycling society of the future, it is necessary to paint a broader picture of what the future of Japanese industry and society will look like, and what technologies will be needed to do so.

*¹ Rare earth: Scandium, yttrium and 17 elements belonging to the lanthanide series. Many of these are indispensable to industrial products, such as neodymium being used to make permanent magnets. In particular, dysprosium and terbium are known as heavy rare earth elements and are very rare.

*² Rare metals: The general term for metals with less circulation such as nickel, cobalt, platinum, and rare earth, which once selected 47 elements (with 17 rare earth elements as 1 mineral, a total of 31 mineral species), and now expanded to 55 elements. Rare earth is the academic term used worldwide, but rare metals are a classification specific to Japan. As a policy term, the names and types vary from country to country.