Life cycle assessment of the production of Portland cement: a Southern Europe case study

The cement industry is one of the most important industries worldwide and the world cement production is projected to grow by 0.8-1.2% per year, reaching between 3700 and 4400 megatonnes in 2050. This industry is facing important challenges in the context of restrained use of raw materials and need of optimization of energy consumption. The aim of this paper is to assess environmental impacts of using wastes as a partial replacement of fossil fuels in a representative cement plant in Southern Europe. Refuse derived fuel and scrap tires were employed as alternative fuels. The environmental profile of the cement manufacturing was presented through a cradle-to-gate life cycle assessment approach based on primary data collected in the plant. The functional unit was 1 tonne of ordinary Portland cement and the impact assessment was based on indicators that comply with the ISO 14040. The impact categories studied were abiotic depletion, acidification, eutrophication, photochemical oxidant formation and global warming. The processes that most contributed to these impact categories were the atmospheric emissions in the kiln, the consumption of fossil fuels, and the consumption of electricity in the mills.