SAVING BEACH WITH SECONDARY AGGREGATES

“We are spending our sand budget faster than we can produce it responsibly.” This statement was made by Joyce Msuya, the UN Environment Deputy Executive Director and Assistant Secretary-General of the United Nations, in the context of the publication of the report > ‘Sand and sustainability: Finding new solutions for environmental governance of global sand resources’.

The corresponding > press release dated 17 May 2019 states that the current global demand for sand and gravel amounts to 40 to 50 billion tonnes per year and is forecast to increase by 5.5 % annually. It continues that the new report “presents how shifting consumption patterns, growing populations, increasing urbanization and infrastructure development have increased demand for sand three-fold over the last two decades. Further to this, damming and extraction have reduced sediment delivery from rivers to many coastal areas, leading to reduced deposits in river deltas and accelerated beach erosion.”

One of the key messages of the report recommends using recycled and alternative materials in the construction sector to reduce mining volumes.

“Society can make more efficient use of sourced aggregates through using substitutes to natural sand where feasible, so that extraction is reduced to responsible levels.”

Source: UNEP 2019. Sand and sustainability: Finding new solutions for environmental governance of global sand resources. GRID-Geneva, United Nations Environment Programme, Geneva, Switzerland: Key messages, page xiv

Secondary aggregates from sources such as building rubble or waste incineration are among sought after substitutes to natural sand and gravel, offering significant potential for the protection of mining volumes. Both material streams are available in significant amounts worldwide, and provide – after expert processing and treatment – the required technical properties use in construction.

More reading:
> Rising demand for sand calls for resource governance
> The search for sustainable sand extraction is beginning
> Sand, rarer than one thinks
> How to steal a river

Construction and demolition waste (CDM) is one of the most voluminous waste streams generated in the EU. The material is the basis for the production of recycled aggregates. Another important source of secondary construction material stems from the 492 Waste-to-Energy plants operated in Europe in form of incinerator bottom ash (IBA).

Europe produces 19 million tonnes of incinerator bottom ash, 85 % of which are of mineral nature. This makes 16.2 million tonnes of IBA available for use as secondary aggregate. A further 335 million tonnes of mineral waste (excluding soil) from construction and demolition works is currently recycled at a rate of 74 % in Europe, making another 249 million tonnes of recycled aggregates available to the market. Main application areas for both materials are road construction, earthworks and concrete production. By replacing natural minerals with these sustainable alternatives, the annual mining volume is reduced by 265 million tonnes each year.

Sources:
> cewep bottom ash fact sheet
> cewep Waste-to-Energy plants Europe
> eurostat waste generation by category
> eurostat waste treatment by category

With regard to sustainability, REMEX focuses on three topics: climate protection, landscape conservation and the optimisation of landfill quotas by maximising recycling and recovery results. The environmental contribution that we achieve through our activities can be quantified, particularly with regard to the production of substitute construction materials, metal recovery and land remediation. To read more, please visit our specially themed webpage > sustainability.remex.de