Urban populations are expected to more than double by 2050, however only about 50% of the required new infrastructure currently exists. Unless we change the way we build and live in cities, this will cause an unsustainable impact on our environment from the associated carbon emissions and the overall demand on resources.

At the same time, construction and demolition (C&D) waste is a significant and growing problem, accounting for 25% of the waste generated globally each year. But these huge piles of waste can also represent an opportunity to reduce the construction industry’s reliance on virgin raw materials. This is particularly true of concrete – the second most consumed material in the world after water and the target of a new research project funded by the Danish EPA (MUDP).

Kicking off in January 2023, the project aims to close the loop for concrete by recycling 100% of demolished concrete into new concrete. This will require technologies that gently but efficiently separate the coarse aggregate fraction from the fine sand and cement fractions, as well as solutions to process the fines into high-quality sand and cement fractions. The project will also explore technologies to refine the cement fraction, which poses the most challenge in terms of recycling. Such an ambition requires diverse perspectives and collaboration across the value chain.

Project partners


Norrecco is one of Denmark’s leading construction waste treatment companies with a primary focus on processing the materials it receives into resources that can be re-used in new construction.


MIS Recycling has partnered with Norrecco for many years, providing concrete crushing equipment and operators. 


PELCON runs a specialist laboratory for aggregate and concrete testing and has worked with recycled concrete since the mid-1980s. 


FLSmidth is one the leading suppliers of cement plant equipment and solutions worldwide. It is committed to finding solutions that reduce the carbon intensity of cement production in order to meet net-zero goals. 


Unicon is Denmark’s leading ready-mix concrete companies and brings its understanding of concrete production, market, and customers to the project.


Aalborg Portland is a leading cement manufacturer, producing both grey and white cement with an annual combined capacity of about 3 million t. 


MUDP is funding the project and will provide administrative support. It also brings awareness of how the results of the project might be translated into legislation.


“We cannot continue to consume raw materials at the current rate. Construction waste must therefore be treated as a resource for future construction. Turning old concrete into new is an important step in this transition to a fully circular construction industry, and we are pleased to be a part of a project that is spearheading efforts to close the concrete loop,” said Jette Bjerre Hansen, Norrecco. 


“This project fits perfectly into our Green’26 strategy to provide services and core equipment to produce green cement. It is an exciting opportunity to gather stakeholders from the complete concrete value chain to investigate the feasibility of 100% concrete recycling. It also allows us to learn how we can spread and share the benefits and burdens. We are particularly looking forward to seeing how our equipment could support full circularity for concrete,” said Bodil Recke, Head of Green Innovation at FLSmidth.

Stories from FLSmidth