Mitigating environmental impact by development of ambient-cured EAF slag and fly ash blended geopolymer via mix design optimization

• Published in: Environmental science and pollution research international Vol. 31; no. 27; pp. 38908 - 38925
• Main Authors: Mishra, Anant, Lahoti, Mukund, Yang, En-Hua
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.06.2024; Springer Nature B.V
• Subjects: Aquatic Pollution; arc furnaces; Atmospheric Protection/Air Quality Control/Air Pollution; Caustic soda; Cement; Cleaner Production and Sustainable Processes for Environmental Remediation; Coal Ash - chemistry; compression strength; Compressive strength; Content analysis; Design of experiments; Design optimization; Design parameters; durability; Earth and Environmental Science; Ecotoxicology; Electric arc furnaces; Emissions; Environment; Environmental Chemistry; Environmental Health; Environmental impact; Environmental science; Experimental design; Fly ash; Fourier transforms; Gels; Geopolymers; Industrial plant emissions; Iron compounds; Mechanical properties; Mechanical tests; Polymers; Scanning electron microscopy; Signal to noise ratio; Slag; slags; Steel production; Waste Water Technology; Water Management; Water Pollution Control; Fly ash; Ambient-cured; Taguchi-grey relational analysis; Geopolymer; Electric arc furnace slag; Optimization
• ISSN: 1614-7499; 0944-1344; 1614-7499
• DOI: 10.1007/s11356-023-26884-8

This article discusses the utilization of industrial by-products, namely, electric arc furnace slag (EAFS) and fly ash to produce cementless geopolymer binder. Taguchi-grey optimization is used for experimental design and for investigating the effects of mix design parameters. Fly ash, in the levels of 0–75% (by mass), partly replaced EAFS in the binary-blended composite system. Experiments were performed on the microstructural development, mechanical properties, and durability of ambient-cured EAFS-fly ash geopolymer paste (EFGP). The optimal mix with 75–25% composition of EAFS and fly ash produced ~ 39 MPa compressive strength accrediting to the co-existence of C-A-S–H and N-A-S–H gels. The initial and final setting times were 127 min and 581 min, respectively, owing to adequate alkali and amorphous contents in the matrix, and the flowability was 108% due to sufficient activator content and the spherical shape of fly ash particles. SEM, XRD, and FTIR results corroborated the mechanical test results. Graphical Abstract