Management and Valorisation of Wastes and Co-products from the TiO2 Pigment Industry

Abstract

This work analyses and evaluates potential applications for several inorganic wastes and intermediate materials, called co-products, generated in the TiO2 pigment production industry through the sulphate method. For this purpose, a physical–chemical characterisation of the input materials (ilmenite and slag), wastes (sludge and red gypsum), and co-products (two ferrous sulphates, mono and hepta-hydrated) was carried out. In addition, because the TiO2 pigment production activity is a Naturally Occurring Radioactive Material industry, a radiological characterisation was also undertaken. The main objective was to gain basic information for the application (actual or potential) of these co-products and wastes in fields such as agriculture, construction, and civil engineering. For each specific application of these wastes and co-products, additional studies were carried out to evaluate their appropriateness with respect to technical properties and their health and environmental impact. The results obtained in this work have revealed several lines of research with potential commercial applications.