Filter Cake Lightweight Aggregate Concrete for Next-Gen Sustainable Construction (FC-LWAC)

The project (FC-LWAC) represents a pioneering approach to sustainable construction materials. This project explores the transformation of Waste-Based Filter Cake materials into lightweight aggregates (LWA) suitable for structural concrete. By diverting industrial waste streams into high-value construction products, FC-LWAC addresses both environmental challenges and the demand for innovative building solutions.

The methodology involves pre-treatment, mineral characterization, pelletisation, and controlled firing of filter cake samples to produce bloated lightweight aggregates with bulk densities around 1 g/cm³ and particle densities below 2 g/cm³. These values align with commercial LWA benchmarks, proving the feasibility of waste-derived aggregates.

The innovation of FC-LWAC lies in its circular economy model, unlike conventional LWAs derived from expanded clay or shale, FC-LWAC leverages industrial by-products, lowering carbon emissions and landfill burdens. This dual benefit, waste valorisation and sustainable construction, positions the project at the forefront of green building technologies.

This project builds on a successful initial trial conducted with the University of East London, where promising results were achieved. Trials confirmed that, concrete cubes using LWAs made from filter cake achieved compressive strengths higher than those of commercial Lytag, with comparable densities. Although pozzolanic activity was limited at lower calcining temperatures, samples fired at 900°C demonstrated strengths approaching or matching plain cement. These findings provide a strong foundation for FC-LWAC, validating its potential and guiding the next phase of industrial adoption.

Lightweight concrete aggregates are important for the UK construction sector, where reducing structural dead loads enables more efficient design of bridges and high-rise buildings. In Wales, where infrastructure renewal and housing development are priorities, LWAC offers...