BauCycle – construction waste recycling

© Fraunhofer IOSB
Der BauCycle-Prozess im Überblick
Optical computing for sorting the fine fraction of construction waste
© Fraunhofer
Optical computing for sorting the fine fraction of construction waste

Short description of the project

Sustainable construction is assuming an increasingly important position in the construction sector. For this reason, a research consortium of four Fraunhofer Institutes has joined forces to address the challenge of resource conservation, reuse of building materials and high-quality recycling of building materials. In the process, the BauCycle project was launched and has been funded since the beginning of 2016 until the end of the project in 2019 as part of the Fraunhofer Gesellschaft's internal programs.

Project goals

The aim BauCycle is to sort and process demolition materials into recycled building materials that can then be returned to the original construction cycle. This is intended to reduce the use of primary raw materials, enable more sustainable construction and counteract the shortage of landfill space.

Project results

The main focus of the Fraunhofer IOSB project was the development of a process for the optical sorting of crushed construction waste in order to selectively separate its main components concrete, brick, sand-lime brick and gypsum. Based on hyperspectral sensor technology and the widely tested IOSB sorting technology, a purity of approximately 99.5 percent was achieved.

In parallel, the project worked on building product samples and formulations. For example, autoclaved aerated concrete blocks were produced in which 30 percent by mass of the primary raw material sand could be replaced by the obtained fine-grained construction waste material, as were cement-free construction materials based on construction waste.

Press releases about the project

May 2020

Optical sorting of building rubble -
and scarce building sand

It is by far the largest waste fraction. More than 200 million tonnes of construction and demolition waste are generated in Germany every year.
Lesen Sie den kompletten Bericht auf der Webseite

29th April 2020 | BauCycle research project draws a positive balance

August 2019

© Fraunhofer IOSB

Recycling of fine-grained construction waste

Many raw materials are becoming increasingly scarce. And this applies not only to oil or rare metals, but also to industrially usable sand. Contrary to the saying that something is as common as sand at the sea, it is finite and in some countries even scarce, because beach or desert sand is not suitable for construction; it is too small and too round.

Read more in the Press release of 8th August 2019.

June 2019

Optical computing for sorting the fine fraction of construction waste
© Fraunhofer
Optical computing for sorting the fine fraction of construction waste

“BauCycle” wins DGNB Sustainability Challenge 2019

The BauCycle project was able to prevail against top-class competitors in the “Research” category of the DGNB Sustainability Challenge and was chosen as the winner of the “Research” category at a specialist event in Stuttgart on June 25, 2019.

Further information can be found on the DGNB website.

Project partners

  • Fraunhofer Institute for Building Physics IBP
  • Fraunhofer Institute of Optronics, System Technologies and Image Exploitation IOSB
  • Fraunhofer Institute for Environmental, Safety, and Energy Technology UMSICHT
  • Fraunhofer Institute for Material Flow and Logistics

Department Visual Inspection Systems of Fraunhofer IOSB

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Project details

BauCycle – construction waste recycling

Project duration: 2016-2019

Award: Winner in the “Research” category of the DGNB Sustainability Challenge 2019

The project was funded by the Fraunhofer-Gesellschaft within the internal funding program MAVO


Field of application: Bulk material sorting

You can find out more about industrial sorting and foreign object detection in bulk materials handling on the pages of our Inspection and Optronic Systems business unit: