Abstract accepted on the International Conference on Sustainability in the Cement and Concrete Industry, 16.-19. September 2007, Norway
The use of sludge incinerator ash in the production of concrete
Pernille Nyegaard, Danish Technological Institute, Gregersensvej, DK-2630 Taastrup, Denmark
Jørn Bødker, Danish Technological Institute, Gregersensvej, DK-2630 Taastrup, Denmark
Claus Pade, Danish Technological Institute, Gregersensvej, DK-2630 Taastrup, Denmark
Bo Neergaard Jacobsen, Avedoere Wastewater Services, Denmark
Dan Kjersgaard, Avedoere Wastewater Services, Denmark
Kim Rindel, Lynettefællesskabet I/S, Denmark
Freddie Larsen, Unicon, Denmark
Incineration of sludge from biological wastewater treatment plants leaves a fine granular waste material. Some 10,000 tons of sewage sludge incinerator ash are produced annually in the Copenhagen area by two incineration plants. The BIOASH represents an environmental problem as it is typically land-filled. For the potential use of bioash in concrete a number of bioash barriers exist relating to the lack of documentation of the influence of the ash on concrete properties. Partial funding by the EU LIFE-Environment programme of the project “BioCrete” made it possible over a 2½ years period starting June 2005 to evaluate the use of bioash in full scale concrete production. The project has comprised documentation of variations in the chemical and physical properties of the ash over an extended production period, and will continue with laboratory castings to document the influence of ash property variations on the properties of fresh and hardened concrete designed for different exposure classes including evaluation of the leaching of heavy metals from bioash concrete. Results of the analyses chemical and physical properties of the bioash is presented as well as results from condition surveys performed on a couple of structures cast with concrete containing bioash.