CEMENTLESS BACKFILL MIXTURES BASED ON WATER-SOLUBLE MANMADE WASTE

Abstract

The relevance of the research is caused by the increasing the impact of mining processing and metallurgical enterprises on the environment. The priority area is the creation and application of sparing geotechnologies that reduce the level of impact of mining and processing production on the ecosystem. The intensification of waste generation from mining, processing and metallurgical industries occurs every year. This leads to an increase in formation of manmade mass. This fact determines the need for their disposal. A good way of disposal is the use of manmade waste of water-soluble ores as an inert filler for preparing a backfill mixture, and to replace the cement binder with magnesium and soda production waste or metallurgical plant slags containing MgO. The main aim of the research is to create a cementless backfill mixture with improved strength and specified rheological properties based on activated manmade waste of water-soluble ores when using magnesium-containing slags of a metallurgical plant as a binder. This will allow implementing the principle of non-waste production. Object: backfill mixture based on activated current halite waste of the galurgic enrichment method of PJSC «Uralkali» (inert aggregate) and magnesium-containing slags of the Chusovsky metallurgical plant (binder), using lignosulfonate to improve the binding capacity and as a regulator of rheological properties. Methodology: the current State standards and approved research methods were applied; tests were performed on calibrated and serviceable equipment; activation was carried out in a laboratory disintegrator DESI-11, samples for compression were tested on a test press PI-2000-A; the rheological properties of the backfill mixture were studied by the slump compression «StroyTSNIL» and by the flowability on a Suttard viscometer; reliability is confirmed by the repeatability of results with a sufficient number of experiments. Results. The permissibility of replacing the cement binder with magnesium-containing waste (slags of the Chusovsky metallurgical plant) is proved. The possibility of using manmade waste of water-soluble ores to replace a specially extracted inert component in the preparation of a backfill mixture was proved. The results of the research on replacing a specially mined inert filler with technogenic waste are presented. The positive effect of mechanical activation treatment of the backfill mixture components on its rheological properties and strength characteristics of the fill mass was investigated. The use of lingosulfonate was confirmed as an additive that improves the binding and rheological properties of the backfill mixture.

Keywords

• non-waste production
• water-soluble ores
• geotechnology
• backfill of mined-out void
• backfill mixture
• mining waste
• manmade waste
• enrichment tails