Production of Ordinary Portland Cement (OPC) from NALCO red mud

Abstract

A process for production of Ordinary Portland Cement (OPC) from NALCO Red Mud has been successfully developed from a raw mix containing limestone, red mud, shale and fine coal. The raw materials are ground to the required fineness and then blended to prepare the raw mix. The raw mix is fed in to a kiln and fired to a temperature of 1400-1450 degree centigrade to obtain clinker. Clinker was cooled and gypsum was added in to it to obtain OPC. 3-3.5% of NALCO red mud was used for production of OPC.OPC prepared from this clinker conformed to the requirements of three Indian Standard Specifications for 33, 43 & 53 grade of OPC. The process is efficient, cost-economic and effectively addresses the environmental problems associated with the waste red mud generated during the refining of bauxite for alumina manufacture.