Analysis of Life Cycle Environmental Impact of Artificial Aggregates

This chapter delves into the analysis of life cycle environmental impacts of artificial aggregates (AAs) derived from industrial waste, focusing on municipal solid waste incineration fly ash (MSWI-FA), ground-granulated blast furnace slag (GGBFS), and marble sludge (MS). The study employs a multi-criteria decision-making (MCDM) model, combining Life Cycle Assessment (LCA) techniques and the Analytic Hierarchy Process (AHP), to evaluate the sustainability of these aggregates. The research explores two production methods: single-step (SSCBP) and double-step cold bonding pelletization (DSCBP), with the latter aiming to enhance the aggregates' technical and leaching qualities. The study's findings highlight that D-AAs 2, composed of 70% MSWI-FA, 30% GGBFS, and 0% MS, emerges as the most sustainable option, boasting the lowest CO2 emissions (0.21 kg CO2 eq.) and freshwater consumption. Conversely, D-AAs 3 demonstrates superior mechanical properties with a crushing strength of 10.94 MPa. The integrated approach of LCA, LCC, and AHP provides a holistic evaluation of the environmental and economic impacts, offering valuable insights into the potential of artificial aggregates as a sustainable alternative to natural aggregates in the construction industry.