Management of hardening mixtures properties when stowing mining sites of ore deposits

Abstract

Underground mining is characterized by the weakening of the bearing rock mass strata competence and the accumulation of mineral waste. The full use of subsurface resources is ensured by the use of technologies with filling voids by hardening mixtures, which requires high-quality raw materials to obtain the required strength. The deficit of the binding component can be filled with the use of granulated slags of blast-furnace process, mill tailings, ash-slags and other wastes. Most often, voids are laid by mixtures with a combination of cement and a binding component. Mixtures with ash-slag additives to cement in an equivalent amount are not inferior to the strength of the mixture only with cement, especially when grinding ash-slag.
 The properties of stowing rock masses when using composite binding components and inert fillers are controlled by mechanical, chemical, physical and energy effects at the stages of preparation and transportation of hardening mixtures. To obtain the active fraction of cement substitutes, disintegrators are used that apply the inertia forces of materials at a high speed of rotation with an increase in high activity indicators and lower energy costs.
 The components of hardening mixtures can be the majority of waste from mining and related industries, which is determined experimentally in specific conditions.

Selection of mining technology at Anhydrite Mine

“…Отработка сульфидных медно-никелевых руд на рудниках Талнаха ведут с полной закладкой выработанного пространства, и, несмотря на то, что рассматривают также варианты применения систем разработки с обрушением, в ближайшей перспективе закладка твердеющими смесями будет являться основным способом управления горным давлением [1,2]. Ангидрит является не только вяжущим элементом, но и пластификатором, обеспечивающим текучесть, благодаря чему закладочную смесь можно транспортировать на более дальние расстояния, при этом снижая риск забутовки [3][4][5].…”

Backfill of a Mined-Out Gold Ore Deposit with the Cemented Rubber-Cord and Waste Rock Paste: Environmental Changes in Aqueous Media

“…Reclamation of old underground mines is required to reduce or eliminate the potential risk of mine subsidence and sinkhole formation, so there is a need to fill the void in a way that minimizes the impact of underground mining [4,9]. From this point of view, backfill is the most optimal way to utilize such waste, which also solves the problem of working out pillars, maintaining workings, and preventing subsidence of the earth's surface [5].…”

“…From this point of view, backfill is the most optimal way to utilize such waste, which also solves the problem of working out pillars, maintaining workings, and preventing subsidence of the earth's surface [5]. The material for filling can be various types of waste, from waste rock and tailings to ash, slag, and others obtained during the processing and use of extracted raw materials [9][10][11][12][13][14]. However, there are several problems in the reclamation of abandoned mines; for example, the material used to fill the voids of underground mines will interact with groundwater in the medium in long term, potentially causing the components to be leached from the backfill material into the groundwater system.…”