Recycling waste tyre polymer for production of fibre reinforced cemented tailings backfill in green mining

Zhenbang Guo; Jingping Qiu; Alex Kirichek; Hao Zhou; Chen Liu; Lei Yang

doi:10.1016/j.scitotenv.2023.168320

Recycling waste tyre polymer for production of fibre reinforced cemented tailings backfill in green mining

Sci Total Environ. 2024 Jan 15:908:168320. doi: 10.1016/j.scitotenv.2023.168320. Epub 2023 Nov 8.

Authors

Zhenbang Guo¹, Jingping Qiu², Alex Kirichek³, Hao Zhou⁴, Chen Liu⁵, Lei Yang⁶

Affiliations

¹ School of Resource and Civil Engineering, Northeastern University, Shenyang, China; Science and Technology Innovation Center of Smart Water and Resource Environment, Northeastern University, Shenyang 110819, China; Section of Rivers, Ports, Waterways and Dredging Engineering, Department of Hydraulic Engineering, Faculty of Civil Engineering & Geosciences, Delft University of Technology, Stevinweg 1, 2628 CN Delft, the Netherlands.
² School of Resource and Civil Engineering, Northeastern University, Shenyang, China; Science and Technology Innovation Center of Smart Water and Resource Environment, Northeastern University, Shenyang 110819, China.
³ Section of Rivers, Ports, Waterways and Dredging Engineering, Department of Hydraulic Engineering, Faculty of Civil Engineering & Geosciences, Delft University of Technology, Stevinweg 1, 2628 CN Delft, the Netherlands.
⁴ Xingshan Iron Mine, Mining Corporation, Shougang Group Co., Ltd., Qian'an, Hebei 064404, China.
⁵ Department of Materials and Environment (Microlab), Faculty of Civil Engineering and Geoscience, Delft University of Technology, Delft, the Netherlands.
⁶ Hopkins Extreme Materials Institute, Johns Hopkins University, Baltimore, MD 21218, USA. Electronic address: lei.yang@sydney.edu.au.

PMID: 37949142
DOI: 10.1016/j.scitotenv.2023.168320

Abstract

The increasing amount of solid waste, e.g., waste tyres from car industry and tailings from mine operations, causes substantial environmental and societal issues. The recycled tyre polymer fibre (RTPF) reinforced cemented tailings backfill (CTB) is a kind of composite that can treat waste tyres and tailings simultaneously and realize green mining, but its engineering properties have not been well understood. In this study, the rheology (i.e., static and dynamic yield stress, and structural build-up), strength (i.e., uniaxial and triaxial compressive, splitting tensile and flexural strengths), microstructure, and life cycle of RTPF reinforced CTB are comprehensively evaluated. For comparison, the engineering performance of the commonly used polypropylene fibre (PPF) reinforced CTB in mines is tested. The experimental results demonstrate that incorporating 0.6 wt% RTPF into CTB can achieve comparable fluidity and strength to the CTB reinforced with 0.3 wt% PPF at reduced cost and improved sustainability. A strength enhancement approach for RTPF reinforced CTB is also developed by adjusting the viscosity of suspending CTB before the addition of RTPF. With this approach, the splitting tensile strength increases by 68 %. The results obtained from this study pave the way for promoting the recycling of abandoned waste tyres and the safe design of backfill structures in mines.

Keywords: Cemented tailings backfill; Microstructure; Recycled Tyre polymer fibre; Rheology; Solid waste utilization; Strength.