Fresh concrete - environmetal aspects
The supply of ready-mixed concrete invariably produces some waste materials and water. With increasing environmental pressure to reduce waste and pollution and to recycle as much as possible, the concrete supply industry has adopted a number of methods to achieve this. The aim is to achieve zero waste for disposal from concrete plants.
A small, yet useful, source of recycled material results from the return of surplus fresh concrete to a concrete plant. Aggregates can be removed and recycled, along with the wash water from the truck, into another batch of concrete. Alternatively admixtures may be used that delay hydration and allow the concrete to be re-used, even on the following day.
These approaches minimise waste and the cost (financially and environmentally) of sending it to a landfill site.
For further information see:
Concrete and the Environment, published in CONCRETE in September 2001, pp 39–46
Recycled aggregates for use in concrete, published in CONCRETE in March 2005, p 43
Towards zero waste, published in CONCRETE in may 2005, pp 50–52.
Copies are available as a free download from the Members Area of the Concrete Society web site.