Evaluation of Functional, Microstructural, Environmental Impact, and Economic Performance of Concrete Utilizing Ferrochrome Ash and Slag

This paper reports on the functional, economic, and environmental performance of sustainable concrete prepared from the waste materials like ferrochrome ash (FCA) and air-cooled ferrochrome slag (ACFS). FCA and ACFS are metallurgical waste materials from the ferrochrome industry, which contain residual chromium and face disposal problems. The leaching of chromium from FCA is reported to be 26 times more than the regulatory limit, as such banned for landfilling. The sustainable management of these metal residues in concrete making through the combined use of FCA (up to 40%) and ACFS (100%) for part replacement of the cement and total replacement of virgin coarse aggregate was examined. The technical performance of such concrete when examined in terms of compressive strength, modulus of rupture, and sulfate resistance has better performances up to 11% than conventional concrete. Environmental performances when examined through global warming potential (GWP), ozone depletion potential (ODP), abiotic depletion potential (ADP), photochemical ozone creation potential (POCP), eutrophication potential (EP), and acidification potential (AP) have advantages up to 47% when compared to normal concrete. The leaching of hexavalent chromium from such concrete is far below the regulatory limit. The economic performance of such concrete is found 22% cheaper than normal concrete. The microstructure of ferrowaste concrete is found denser than control concrete. Graphical Abstract