Development of environmentally sustainable cement compositions based on processed ceramic waste

One of the major challenges in the modern construction materials industry is the development of environmentally sustainable, energy-efficient, and economically viable materials. This study investigates the production of composite cement compositions by partially replacing Portland cement clinker with recycled ceramic brick waste (CBW). The primary objective is to reduce carbon dioxide (CO₂) emissions during cement manufacturing by utilising secondary raw materials with pozzolanic and filler properties. The experimental program encompasses a comprehensive analysis of the chemical, mineralogical, and structural characteristics of CBW, as well as its impact on the hydration process and the mechanical properties of cement composites. The clinker was partially replaced with CBW at 15% and 20% by mass in the binder component. Mechanical strength tests (flexural and compressive) were conducted at 2, 7, and 28 days of curing. Additionally, phase composition was analysed by X-ray diffraction (XRD), and microstructural development was evaluated using scanning electron microscopy (SEM). The results show that replacing clinker with CBW improves the microstructural compactness of the hardened matrix and ensures comparable mechanical performance after 28 days. A Life Cycle Assessment (LCA) confirmed that this approach can reduce CO₂ emissions by approximately 15–25% compared to conventional cement. The scientific novelty lies in the combined pozzolanic and micro-filler role of CBW, enabling its use as a supplementary cementitious material in low-carbon binder systems. The findings support the development of sustainable technologies for the cement industry and promote the circular economy through the utilisation of industrial waste.