Transformation of waste-contaminated glass dust in sustainable fired clay bricks

Abstract

The management of glass waste has been a major crisis due to its bulk production and fewer recycling approaches adopted in the present industry. This has challenged the researchers and authorities to explore further development of innovative recycling strategies that would enable the utilization of glass wastes at large scales following circular economic principles. The current research aims to develop a strategy for translating waste-contaminated glass dust (WGD) into manufacturing fired clay bricks, a completely new use of glass dust that is fundamentally different from glass wastes commonly explored in literature. A comprehensive set of physico-chemical tests such as compressive strength, water absorption, initial water absorption, thermal conductivity tests, X-ray fluorescence (XRF) analysis, SEM analysis, X-ray diffraction (XRD) analysis, 3D-CT scanning and salt resistance tests were conducted to evaluate the physical, mechanical, environmental, durability and morphological characteristics of the bricks. Additionally, in-depth heavy metal leaching investigations were undertaken on WGD bricks to assess the environmental impact. The results demonstrated that novel brick produced from 15 % WGD (by weight) is highly energy efficient, demonstrating less firing temperature (by 5–10 % reduction compared to industrial brick firing temperature) requirement and improved thermal performance (>10 %) compared to standard clay bricks while satisfying the other compliance requirements based on national standards. This study provides a viable solution to the problem of waste accumulation, environmental issues, financial burden and raw material shortages by blending WGD into bricks.

Keywords

• Waste management
• Fired clay bricks
• Sustainability
• Waste glass dust
• Recycling