Life Cycle Assessment of Sugarcane Bagasse Ash as Partial Cement Replacement in Concrete
Saznizam Sazmee Sinoh, Zainah Ibrahim, Faridah Othman, Lee Meng Kuang, Ahmad Zaki
Abstract
Concerns on the environmental impacts from use of concrete in the construction industry are becoming more widespread. Past and current research trends indicate that cement represents the bulk of emissions from concrete. Thus, its replacement significantly reduces negative impacts in concrete. Incorporation of industrial and agricultural waste products have shown to positively influence properties of concrete. Particularly, sugarcane bagasse ash (SCBA) has shown promising use as a cement replacement, but its environmental performance has not been thoroughly explored in the literature. This study investigates the environmental impacts of concrete with 10% cement replacement by SCBA using a life cycle assessment approach. The results were compared to normal concrete with compressive strength of 45 MPa. A school building was selected as a case study for LCA calculations. The total volume of concrete was obtained through a digital building model constructed using building information modelling (BIM) approach. The Ecoinvent database was used to construct the life cycle inventory while ReCiPe 2016 was used as the impact assessment method. Impacts were presented in the form of 17 midpoint categories. Results show that use of SCBA concrete reduced environmental impacts by an average of 5.5% in all but 3 impact categories. A small increase was observed for water use (1.6%) while significant increases in impacts were observed for ozone depletion (7.4%) and land use (58.4%). Furthermore, approximately 3% cost reductions were achieved when using SCBA concrete over normal concrete.