The effect of the scrap/DRI ratio on the specification of the EAF dust and its influence on mechanical properties of the concrete treated by its dust

摘要

Electric Arc Furnace Dust (EAFD) is a by-product of steel production. One of the most suitable ways to immobilize this toxic waste is adding it to the concrete mixture. According to the increasing trend of the world cost of the scarp and decreasing scrap sources, some manufacturing plants prefer to use the Direct Reduced Iron (DRI) instead of the scrap. This study investigated the characteristic of EAFD samples with different scrap/DRI ratio by XRF, XRD, SEM and BET analysis. It has been observed that zinc oxide (ZnO) content varies from 1.5 to 9.7 wt% while scrap/DRI ratio increases from 0 to 0.724. The produced EAFD was added to Portland cement concrete mixture in different amounts (0, 5, 10 wt%). It was found that the initial setting time of the concrete specimens was retarded by adding the EAFD with different scrap/DRI ratio. Moreover, addition of 10 wt% EAFD from 0 to 0.724 scrap/DRI ratio increased the compressive strength of the concrete specimens up to 55.1 MPa. (C) 2016 Elsevier Ltd. All rights reserved.