A path to carbon neutrality in construction: An overview of recent progress in recycled cement usage

The cement industries as binder materials, produces 1.6 billion metric tons’ carbon dioxide (CO2) in 2022 and cause depletion in ozone layer. The cement is being used in modern construction and cause the environmental impact. Therefore, there is a quest for a sustainable alternative binder to reduce the CO2 emission from the conventional cement production and their effective disposal methods in construction and demolished (C&D) waste is paramount. This article delves into the production of recycled cement by leveraging various methods such as mechanical activation, chemical activation, and heat treatment of C&D waste, ultimately contributing to the carbon neutrality. A comparison with traditional cement production sheds light on energy consumption, CO2 emissions, and resource utilization. The recycled cement displays increased water demand, accelerated early setting, extended final setting time, and reduced compressive strength. However, when used solely as a cementitious matrix, recycled cement can readily achieve up to 30 MPa in 28 days. Utilising recycled cement in concrete applications demonstrates its efficacy in the construction industry. The insights provided herein offer a holistic understanding of the production processes, properties, and applications of recycled cement, reinforcing its potential as a viable and environmentally friendly alternative in the realm of construction materials.