Urban mining means “mining in the city” or “urban prospecting”. The principle: extract raw materials from existing sources such as buildings instead of extracting them from nature. To extract secondary raw materials from them, to conserve natural resources and to reduce expensive imports. To secure the livelihoods of existing and future generations.
Everyoneis talking about a shortage of raw materials. We have a lot of raw materials. You just have to look closely. And grab it when the time is right. For example, huge mountains of materials have been found in houses, floors, consumer goods or infrastructures for decades. Their potential as a future source of secondary raw materials is enormous. Buildings in particular contain a lot that can be reused and reused: windows, heating, the concrete from the walls, the tiles from the roofs, the gravel under the foundations, the wood from a wide variety of fixtures. Look out the window! The material warehouses of tomorrow are right under your nose.
According to the Federal Environment Agency, urban mining is “the integral management of the anthropogenic repository with the aim of extracting secondary raw materials from durable goods and deposits”. In other words, urban mining considers everything from electrical appliances to cars to buildings and supposed waste from landfills as a treasure trove for secondary raw materials. By the way, it doesn’t matter whether it is still actively used and only released in the foreseeable future, or already at the end of the horizon of use. A special discipline of urban mining is so-called landfill mining. It refers to the extraction of recyclable materials from old landfills.
Detecting, exploring, indexing, extracting, processing. These are the individual steps for effective urban mining. Although the work actually starts or should start much earlier, namely with production (“cradle-to-cradle” principle). In the construction sector, for example, material passports (digital data sets) reveal which raw materials were used where and in what quantities. For new buildings, these passports are highly recommended, as they are crucial tools for more circularity in the construction industry and important documents for all current or future stakeholders. With older buildings, things are a bit more difficult. However, data such as the year of construction and location as well as the origin and quality of the materials used provide information or at least estimates.
Urban mining includes five key questions:*
- Where are the raw material warehouses?
- How many and which materials are contained that can be used as secondary raw materials?
- When will the warehouses for raw material extraction become available?
- Who is involved in the development?
- How can material cycles be effectively closed?
The advantages of urban mining at a glance:
- Cost savings due to fewer imports of raw materials
- CO2 reduction through fewer transport trips to landfills
- Conservation of natural resources, which are becoming increasingly scarce
- Less waste in landfills
- Less illegal waste disposal abroad
- Nature’s possibilities for regeneration
- Better understanding of material and building values
A good example of effective urban mining is Germany’s best-known large-scale construction site in the north of Munich on the site of the former Bavarian barracks. Here, new material is produced from supposedly worthless construction waste, which can be reused on site. For roads, green spaces, buildings.
