Influence of metallurgical slag additives on proppants synthesis processes based on drilling muds

Abstract

The slags formed during the smelting of ferrous alloys consist of more than 75% oxides of calcium, iron and silicon that predetermines broad prospects for their use as an alternative to natural raw materials. Considering the significant amount of alkaline earth oxides (calcium and magnesium) in the metallurgical slag, it seems promising to use it as a fluxing additive in highalumina aluminosilicate materials, one of which is proppants – granular aluminosilicate materials designed to enhance oil production by hydraulic fracturing. The aim of this work is to study the effect of metallurgical slag additives on the processes of proppant synthesis based on drill slurry. The composition of the initial drill slurry from the Morozovskoye deposit and the fluxing additive of metallurgical slag of JCS “TagMet” was studied. Based on the composition of the metallurgical slag, an assumption was made about its fluxing activity in the synthesis of silicate materials, which is due to a large amount of alkaline earth metal oxides, a low intensity of the crystalline phase and the presence of preliminary heat treatment. Five compositions of raw mixtures for the production of proppants were developed with the addition of two types of fluxing additives: metallurgical slag and sodium hydroxide. Qualitative (texture and color) and quantitative (density and sintering coefficient) parameters of the degree of sintering and melting of mixtures were determined. It was shown that both additives have a fluxing effect on drill slurry. It was found that the introduction of metallurgical slag leads to a change in texture to a more sintered one, as well as an increase in density and sintering coefficient. The introduction of sodium hydroxide has a more active effect on drill slurry, which leads to glass formation of the surface and further melting of the material. Physicochemical processes under the fluxing effect of the selected additives were considered, which is explained by the formation of more low-melting silicates, which reduce the final melting temperature of the mixture. The work was performed at YuRGPU (NPI) with the financial support of the Russian Science Foundation under the Agreement No. 20-79-10142 “Development of an effective technology for synthesis of aluminosilicate proppants using waste of drilling oil and gas wells of the Southern Federal District” (head – A. A. Tretyak).