• Wyss Academy

Replacement of raw materials in the circular economy

BERN HUB | Project AWA-1

Our goal:

By means of detailed material examinations, we aim to estimate the recycling potential of mineral waste and, in cooperation with the industry, increase the recycling rate of secondary raw materials in the construction industry (e.g. in clinker production) as well as to find new possible applications. This will save primary raw materials and close material cycles.

While metals are already being recovered from waste slag, the foundations for the recovery and recycling of mineral residues are yet to be created. / Photo: Mirjam Wolffers

In a nutshell:

A large part of the waste volume in Switzerland - and in the canton of Bern - is mineral waste from excavation, demolition and dismantling work which are today landfilled in large quantities, as often no direct recycling is possible. Furthermore, residues from waste and wood incineration plants are an additional source of mineral waste. While metals are recovered from the incineration residues; the entire mineral portion of these residues is deposited in landfills and consequently lost to the mineral raw material cycle.

Besides placing a heavy burden on Switzerland's limited landfill volume, valuable raw materials are also lost to the cycle. Additionally, the procurement of new building materials, so-called primary raw materials, is very energy and CO2-intensive. Their recycling therefore reduces the amount of waste as well as the environmental impact. The resulting secondary raw materials can be reused in the local construction industry. Many demolition materials classified as "low-grade" nevertheless have a potential for recycling. Thus, in order to preserve primary raw material resources and close material cycles, the silo mentality must be broken down and synergies should be exploited.

This project makes a valuable contribution to the closing of raw material cycles by establishing the necessary basis for the recycling of secondary raw materials. It identifies and characterizes all mineral primary and secondary raw materials available today in the canton of Bern in order to estimate the potential for their recovery, recycling and up-cycling in the construction industry. For a secondary raw material (e.g. demolition material) to replace a primary resource (e.g. gravel), it must meet specific requirements. The necessary requirements for further processing into a secondary raw material are identified together with the recycling industry (e.g. cement plants).

Landfill space in Switzerland is scarce. The project aims to create the necessary foundations to increase the recycling rate, especially in the construction industry. / Photo: Urs Eggenberger

Building on the first phase of investigating the recycling potential, specific implementation trials (laboratory and pilot projects) will take place in a second phase. The project is intended to contribute to the knowledge base for the production of a clinker consisting entirely of secondary raw materials as well as to identify further new application possibilities. The knowledge gained should be applicable nationwide as well as internationally.

To establish the necessary foundations for a clinker consisting entirely of secondary raw materials, pilot projects and tests in the cement plant are envisaged. / Photo: Urs Eggenberger


In collaboration with:

Amt für Wasser und Abfall des Kantons Bern AWA (Office for Water and Waste of the Canton of Bern)

With support from IT company Fink & Partner: LIMS-Software