Mechanical and Leaching Properties of Solidified Clinical Waste Incinerator Fly Ash Mortar

• Published in: Lecture Notes in Civil Engineering
• Main Author: Ghazali E.; Megat Johari M.A.; Fauzi M.A.; Md Nor N.
• Format: Conference paper
• Language: English
• Published: Springer Science and Business Media Deutschland GmbH 2024
• Online Access: https://www.scopus.com/inward/record.uri?eid=2-s2.0-85181984645&doi=10.1007%2f978-981-99-6018-7_39&partnerID=40&md5=ba40434a16657797e9b48647282a482a

With the rise of COVID-19 pandemic cases, the volume of clinical waste delivered to incinerator plants from hospitals, clinics, laboratories, temporary quarantine centres, and research institutes worldwide has increased significantly. These incinerator plants will produce clinical waste incinerator fly ash (CWIFA), which will overburden the landfill if all is placed there, but it has the potential to be utilized as a supplementary cementitious material in cement mortar or concrete. The goal of this cement-based mixed CWIFA (0, 2.5, 5, 10, and 15% as a partial cement replacement) research is to study the strength, the leachability of heavy metals, and the resistance to chloride ion penetration of the mortars with CWIFA inclusion. This will enable this CWIFA to be used in construction, while being disposed of safely in landfills that only need minimal environmental protection. The solid mortar leaching behaviour and mechanical properties were investigated with a ratio W/C of 0.485. Results show that adding 2.5% CWIFA as cement replacement in mortar mixture achieved the highest compressive and flexural strength of 41.04 MPa and 8.00 MPa, respectively. Further increase in CWIFA content in the mortars reduced compressive and flexural strengths. The rapid chloride permeability (RCP) values also increased with the inclusion of CWIFA in the mortar mixtures. A toxicity characteristic leaching procedure (TCLP) test performed on all solidified mortar mixtures portrays that the heavy metals investigated (Cd, Cu, Ni, Pb, and Zn) are strongly immobilized by the cementitious matrix. Therefore, 2.5% CWIFA as cement replacement in mortar is better to be utilized in mortar due to good strength, RCP, and leaching results. © The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd 2024.