High performance concrete from recycled water: AquaCem

Concrete is the most used construction material in the world. Concrete itself is a mixture of cement, water and aggregates comprising sand and gravel or crushed stone, and, if applicable, admixtures, additions or fibers. Cement and water are functioning as binder. Either fresh concrete arrives ready-mixed from a factory or batching plant at the construction site or it will be mixed on site. Ready-mix concrete is often preferred instead of concrete mixing on-site because of the precision of the mixture.

Replacing fresh water by recycled water to fabricate high quality concrete

Concrete has large recycling potential in its solid state. However, in many European countries the problem of re-using huge amounts of water needed to clean the mixing trucks at ready-mixed plants is still unsolved. The CORNET project AquaCem focusses on the reuse of this ‘grey water’ for the production of new high quality concrete. Grey water contains fine particles and its use is therefore not permitted in the fabrication of air-entrained and high performance concretes. The goal of AquaCem is to use grey water for the production of air-entrained and high performance concretes that have the same high quality as those produced while using fresh water.

Innovative solutions that will strengthen the sustainability approach of the whole industry while reducing costs

AquaCem aims at studying the reuse conditions of the ‘grey water’ resulting from cleaning the mixing trucks on ready-mixed plants in the three involved countries (Belgium, Austria and Germany). For this purpose, various starting points will be evaluated: different artificial and real ‘grey waters’, different densities of ‘grey waters’ and, partially, hydration stopping agents. The research results will enable the establishment of a code of good practice for total concrete recycling.

Business potential for all concrete manufacturers, raw material producers, material end-users and the construction industry

The market for ready-mixed concrete is huge and growing fast internationally. The re-use of ‘grey water’ for the production of new high quality concrete interests

the whole sector of concrete manufacturing and indirectly the raw material producing industries as well as the material end-users like pre-fabrication and contractor market sectors. It also touches almost the whole construction industry dealing with concrete. The CORNET approach is bottom-up and, therefore, the respective industries in all three involved countries will directly benefit. Belgium produces 11 million m³ of concrete per year that corresponds to one m³ per inhabitant. From the 270 ready-mixed concrete plants in Belgium, almost 60 % are SMEs. In Germany more than 99 % of all companies are categorized as SMEs. The ready-mixed concrete industry in Germany produces 40-50 million m³ per year involving 1,941 plants and a total of 9,500 employees. Austria has also a generally SME-driven industry (95 %). The annual turnover for ready-mixed concrete is about 9.6 million m³, produced in 216 ready-mixed concrete plants.

Participants from Belgium-Wallonia

CRIC-OCCN – National Belgium Research Centre for the Cement Industry – Coordinating Association and Researcher
Contact: Dr. Christian PIERRE (c.pierre@cric.be )
Head of Research Department / CRIC – OCCN
Tel: +32 (0)2 626 89 23
www.cric.be

Participants from Germany

VDZ – VDZ gGmbH Research . Technology – Association
FIZ – Research Institute of the cement industry – Researcher
Contact: Dr. Christoph Müller (christoph.mueller@vdz-online.de)
Head of Concrete Technology / VDZ gGmbH
Tel.: +49 (0)211 45 78-372
www.vdz-online.de

Participants from Austria

VÖZ – Association of the Austrian Cement Industry- Association
SMG – Smart Minerals GmbH – Researcher
Dr. Stefan KRISPEL (krispel@smartminerals.at)
Managing Direktor Smart Minerals GmbH
www.smartminerals.at