The use of basalt aggregates in the production of concrete for the prefabrication industry: Environmental impact assessment, interpretation and improvement

This study aims at environmentally assessing the most significant input and output flows related to the production of concrete using basalt aggregates. For this purpose, Life Cycle Assessment (LCA) was applied according to the ISO 14040:2006 and 14044:2006. All data used were collected on site based on observations during site visits, review of documents and interviews with technical personnel and management. They were processed by using SimaPro 7.3.3, accessing the Ecoinvent v.2.2 database and using the Impact 2002+ method. The LCIA results show that the most impacting phase is the production of the basalt aggregates, with "Human Health" being the most affected damage category because of the emissions to air, of 2.7 kg of particulates (grain size <2.5 μm). In addition to this, the concrete production causes, mainly, the emission, in air, of 465 kg of Carbon Dioxide and the consumption of 37.37 kg of crude oil, per cubic metre of concrete, affecting, the damage categories "Climate Change" and "Resources" also. Regarding "Ecosystem Quality", the occurred damage is due to the emission to air, of 29.6 g of Aluminium and of 251 mg of Zinc into the soil per cubic metre of concrete. Based on the obtained results, the increase of the amount of water used for particulates removal during the basalt extraction phase was assessed. Furthermore, the alternative use of limestone aggregates was assessed from both technical and environmental perspectives. The analysis developed highlighted a total damage decrease of 67%.