Production and characterization of low-energy Portland composite cement from post-industrial waste

The utilization of post-industrial waste materials is often challenging due to environmental regulations. Additionally, the scarcity of raw materials for producing cement is generating the demand for alternate sources of materials. The current study explores the production of cement and clinker on a large scale using post-industrial waste materials from different sources. Lime sludge generated by the paper mill industry and sponge iron produced during the processing of iron are used as primary source materials for producing clinker. A large-scale vertical kiln is used for clinkering. The unburnt carbon present in the sponge iron is used as an energy source for calcining the raw materials reducing the demand on external fuel. A Portland Composite Cement (PCC) is produced by inter-grinding the clinker with waste generated by the pharmaceutical industry, silico-manganese slag and fly ash. An evaluation of the clinker and the PCC is performed and compared with a commercially available Ordinary Portland Cement (OPC). Hydration studies and characterization of the materials are performed using different analytical techniques. This work provides the fundamental basis for an environmentally sustainable utilization of post-industrial waste in the production of clinker suitable for use in construction. (C) 2019 Elsevier Ltd. All rights reserved.