Mineral resource base of Kazakhstan for the production of window glass

Abstract

The chemical compositions of natural and man-made raw materials of Kazakhstan: quartz sand, quartzite, aluminum, calcium and alkali-containing components used in the production of window glass are investigated. According to the chemical composition, all quartz sand deposits meet the requirements of GOST, except for the content of iron oxide. To use quartz sands in the production of flat glass, it is necessary to enrich them. Chemical compositions of feldspar, quartz-feldspar, pegmatite, kaolin have been studied. Deposits of high-quality feldspar raw materials have been found in the Khantau, Maikul deposits (Zhambyl region), in Kostanay (Bisembaevskoye and Marinskoye pegmatite deposits) and Akmola regions (Zerendinskoye field). Alekseyevsky kaolin is of interest, with a high content of aluminum oxide (38.2 %) and a low content of iron oxide. There are quite large reserves of limestones and dolomites in the Republic of Kazakhstan, including the Karatau, Talgar and Shieli deposits. Reserves of chalk with a calcium carbonate content of 94-98 % and insignificant iron oxide are available in the Mangistau region. Kazakhstan has deposits of natural sodium sulfate in the form of solid deposits and brine of numerous lakes. The phase composition of local quartz sands and feldspar has been studied by X-ray phase analysis. Compositions have been developed and experimental glass cooking has been carried out. The content of silicon oxide as the main component in the initial quartz sand is 99.1 %, and the coloring glass of iron oxide is 0.08 %. Therefore, the enrichment method was used to reduce the content of iron oxide in the sand.Studies have shown that magnetic separation can reduce the Fe2O3 content from 0.08 to 0.06 %, by washing from 0.08 to 0.05 %, by flotation to 0.03 %. The size of quartz sand is within the limits that do not complicate the glass cooking process:the content of large grains larger than 0.8 mm is 0.3 %, small grains smaller than 0.1 mm -3 %. The mass fraction of the heavy fraction with a density of more than 2900 kg/m3 is -0.2%. According to complex indicators, the sand corresponds to the VS-030-1po GOST 22551-90 brand. The characteristic intervals of changes in the viscosity of cooking, production, molding, annealing and the corresponding temperatures are determined. The values of the physico-chemical and technological properties of the glasses were obtained by the calculation method. A schedule of annealing of flat glass has been developed.