Key theory and technology of cemented paste backfill for green mining of metal mines

Abstract

To reduce or eliminate environmental damage during mining processes, green mining practices have emerged as a focal point in China’s metal mining research. Cemented paste backfill technology plays a pivotal role in promoting green mining within the metal industry. The technology allows safely backfilling of surface tailings into underground mining airspaces, effectively addressing the challenges associated with tailings storage and underground goaves. In this paper, we introduce the paste rheology theory system, which forms the theoretical backbone of cemented paste backfill. We delve into key technologies such as paste thickening, mixing, transportation, and the use of economical, low-carbon materials. Additionally, we analyze macro and micromechanical properties, in-situ performance monitoring, barricade construction, intelligent control, and numerical simulations of the process. We establish several demonstration projects, both domestic and international, that utilize cemented paste backfill technology to foster greener mining practices. Cemented paste backfill technology is widely used all over the world. It has evolved from its initial stages to being recognized as an advanced application by various ministries and commissions. Ultimately, we propose future research directions for cemented paste backfill technology in the context of eco-friendly metal mining. These perspectives encompass theory, technology, equipment, and mode, which can strongly contribute to the sustainability of the mining industry in China.

Keywords

Cemented paste backfill / Green mining / Paste rheology / Mine tailings / Low-carbon cementitious materials / Intelligent backfill

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