Using slag as sorbent to remove phosphorus from wastewater

International audienceConsidering the EU legislation on phosphorus rejected in the surrounding environment including forwastewater treatment plant having a capacity less than 2000 People Equivalent (see Water FrameworkDirective [2000/60/EEC]), it appears that using additional filter systems filled with reactive materials rep-resents a valuable solution to remove phosphorus in small wastewater treatment plants such as sand fil-ters, constructed wetlands or waste stabilization ponds. To answer this new need, SLASORB waslaunched back in July 2009. The first part of the project was devoted to the selection of relevant slag inEurope to enable the design and the use of slag into demonstration scale filter for treating phosphorusfrom wastewater. The second part of the project was devoted to the design and construction of 2 demon-stration scale filters and to see the technical feasibility of using slag for phosphorus removal in existingwastewater treatment plants representative both of the French and German market. The third part of theproject was mainly focused on the economical feasibility of using slag filters for wastewater treatment. Onthe one hand the potential of recycling slag saturated with P as fertilizer was studied, on the other thecommercial offer and both the market price and demands were studied. The main objective of each WPKwill be presented in this summary.Despite a short project extension (the project ended up in Dec 2012 instead of July 2012) we can say thatthe main objectives of SLASORB were reached: Slag have been shown to be a valuable reactive materialfor P removal in Europe, technical and economical feasibilities have both been established, demonstrationscale systems were able to remove a significant amount of P without any environmental issues associated