Page 4 - Circular Economy - Andrew J. Minson

point of view

• Concrete uses secondary aggregates from other industries Going further, it is useful to also communicate:
– (Closing resource loops for other industries).
• Society’s demand for building materials outstrips what is
• Cement/Concrete uses by products from other industries to available from demolition, so virgin materials are needed.
replace cement clinker – (Closing resource loops for other For these virgin materials responsible sourcing should be
industries). specified.
• Clinker manufacture uses waste as fuel and raw material (co- • The demolition industry should be encouraged to maximise
processing) – (Closing resource loops for other industries). recovery of hard demolition waste.
• Concrete can enable optimised design solutions because it • The system boundary for recycled concrete aggregates
is versatile (in constituents, production, how/where it is cast, should be the whole aggregates industry and not the
design, finish and texture) – (Narrowing resource loop). subset of concrete, to avoid perverse outcome of virgin
• Concrete can be used for design for disassembly (DfD) – aggregates begin transported from A to B and recycled
(Closed resource loop). concrete aggregates from B to A.

6. conclusIon
Country example: UK and Recycled/Secondary Aggregates
Circular economy is a term widely used and encompasses many
The UK Mineral Products Association (MPA) reports that different aspects of sustainable production, sustainable use
of total aggregates the share of recycled and secondary and responsible end of life re-deployment of resources. There
aggregates has increased from 10% in 1990 (MPA 2019) to is a strong story to communicate on the circular approaches
28% in 2016 (MPA 2018). It has stabilised at this higher figure embedded in the production side of the cement and concrete
for almost a decade – a figure that is approximately 3 times industry, especially with use of by-products from other industries.
the European average. Partly as a result of a landfill tax, there And there is a strong story for subsequent life stages through to
is little evidence of hard demolition waste going to landfill. end of life when concrete can be crushed and reused. Further
Recycled and secondary aggregate sources can only satisfy research to improve technical understanding and practical
less than a third of total demand. What this communicates implementation of using demolition waste and by-products
is that society is demanding more materials than can be from other sectors and industries into the cement and concrete
supplied by recycling alone and that the industry is already industries will enable our industry to continue, and increasingly,
acting responsibly in doing what it can. to play its part in delivering society’s need for infrastructure and
buildings in an environmentally responsible way.
In terms of recycled aggregates and concrete, The
Concrete Centre, reports annual UK industry sustainability rEfErEncEs
performance. Many metrics have a target, but the use of
recycled aggregates in concrete is one metric for which [1] Concrete Sustainability Council, “Technical Manual - Version
there is no target. This is in recognition that optimum use of 2.0 (Recycled Aggregates)”, 2019.
recycled and secondary aggregates might not be back into
concrete. It recognises that the system of relevance is all [2] Ellen Macarthur Foundation, “Circular Economy in India:
construction aggregates and not concrete alone. Rethinking Growth for Long-Term Prosperity”, 2016.

[3] European Commission, “Building Sustainability
Performance - Level(s)” web page accessed Nov 2019

https://ec.europa.eu/environment/eussd/buildings.htm

[4] Global Cement and Concrete Association, “GNR – GCCA
in Numbers” web page accessed Nov 2019 https://

gccassociation.org/sustainability-innovation/gnr-gcca-in-

numbers/

[5] Global Cement and Concrete Association, “GCCA
the use of recycled/secondary aggregates as a proportion Sustainability Guidelines for Co-Processing Fuels And Raw
of total aggregates used in concrete in the uK (the Materials in Cement Manufacturing”, Oct 2019.
concrete centre 2019).
[6] MPA, “Summary Sustainability Data 2017”, 2018.

22 The IndIan ConCreTe Journal | JanuarY 2020