In this blog post, we will examine the concept and value of the urban mining industry—which recovers metals and rare resources from electronic waste—as well as the current state of the industry in South Korea and the challenges that lie ahead.
The urban mining industry (hereinafter referred to as “urban mining”) refers to the industry that recovers and recycles resources from various types of electronic waste using specialized processes. The concept of urban mining first emerged long ago when a research team led by Professor Michio Nanjo at Tohoku University in Japan coined the term “urban mining” to describe the “recycling” of metals used in electronic products.
A key point in understanding the concept of urban mining is that, contrary to popular belief, the “resource recycling” carried out in this industry is not macro-level recycling but rather micro-level recycling.
In other words, urban mining refers to a resource recycling industry based on a micro-level concept—the “re-extraction” of various resources contained within devices in their pure forms—rather than macro-level recycling, which involves reusing components such as keyboards or LCD screens as-is. The types of resources recovered are also extremely diverse, ranging from relatively common metals like gold and silver to rare metals such as lithium. In particular, it differs from conventional recycling in that the recovered resources are re-extracted in a pure form with a purity of 99% or higher.
So, what process allows for the re-extraction of resources in their pure form from electronic waste? The general process of urban mining can be summarized as a method that separates and recovers resources through multiple stages of physical and chemical treatment. Since the treatment process varies depending on the target resource and involves diverse and complex physicochemical reactions, it is difficult to explain the process in detail. Therefore, we will briefly examine only the common processing steps here.
One might ask, “How much metal can actually be extracted from household appliances?” However, the actual amount is quite substantial.
When compared to the reserves in natural mines, the amount of resources accumulated in urban mines is by no means negligible. In Japan, for example, it has been found that a considerable amount of metal resources is accumulated in urban mines, and considering South Korea’s massive consumption of electronic products, it can be assumed that a significant amount of urban mining resources also exists in South Korea.
Furthermore, the concentration of resources in urban mining is far higher than in typical natural mines. Take gold as an example. Refining one metric ton of gold ore yields approximately 5 grams of gold. In contrast, it has been reported that roughly 400 grams can be recovered from discarded cell phones, 52 grams from computers, and about 20 grams from other household appliances.
Urban mining, which had not received much attention for some time because extraction from natural mines was more economical than recycling, is once again gaining attention as an essential future industry. This is due to growing concerns about the stability of resource supplies, driven by the steadily declining reserves of natural mines and the use of resources as diplomatic weapons. In Japan, Germany, and Belgium—countries where the urban mining industry has reached the world’s highest standards—it has firmly established itself as a key sector of the national economy.
However, there is still much room for improvement in South Korea’s urban mining sector. Related technologies lag significantly behind those of developed countries, and the technological gap is particularly wide when it comes to rare metal extraction—the core of urban mining. Furthermore, the extremely low volume of electronic waste being fed into the urban mining process is also a problem. Although countless discarded electronic products suitable for urban mining are generated every year, recovery rates remain low due to an inefficient recovery system—where the responsible party for recovery is unclear—and a lack of public awareness. Even when such products are recovered, they are often diverted to other uses or disposed of through methods such as landfilling or incineration.
Given this situation, South Korea is, in fact, a country that needs to take a more proactive approach to resource recycling through the development of urban mining technology than any other nation. This is because, while it has the electrical and electronics industries—which require large quantities of rare resources such as rare earth elements—as its core industries, its self-sufficiency rate for these resources is very low, making it extremely vulnerable in terms of resource security.
At a time when the stable supply of resources is becoming increasingly uncertain, cooperation between the government and industry, as well as efforts by the academic community, to develop relevant technologies are considered more urgent than ever.
