CC BY
7
_ХИМИЧЕСКИЕ НАУКИ / CHEMISTRY_
DOI: https://doi.org/10.23670/IRJ.2021.108.6.035
О НЕКОТОРЫХ АСПЕКТАХ ВЗАИМОДЕЙСТВИЯ КОМПОНЕНТОВ СТЕКОЛЬНОЙ ШИХТЫ ПРИ ТЕРМООБРАБОТКЕ ПО СОДЕРЖАНИЮ СТЕКЛОФАЗЫ
Научная статья
Сидикова Т.Д.* ORCID: 0000-0001-8745-6710, Ташкентский государственный транспортный университет, Ташкент, Узбекистан
* Корреспондирующий автор (taxira-dalievna[at]mail.ru)
Аннотация
Приведены обобщенные данные по синтезу стеклокристаллических материалов на основе флотоотходов. Разработаны оптимальные структуры стеклокристаллических материалов и получения технологических параметров на основе композиции Каолин-кварцовый песок-флотоотход Флюоритовой обогатительной фабрики (ФОФ). Определены физико-химические свойства стеклокристаллических материалов.
Целью данной работы является исследование получения стеклокристаллического материала при низких температурах синтеза (не превышающих 900оС).
Была изучена шихта для получения стеклокристаллита следующего химического состава (%*): 69,00 SiO2, 7,80 AhO3, 1,56 Fe2O3, 3,65 CaO, 0,10 MgO, 0,15 BaO,12,70 Na2O, 1,70 K2O, 4,50 CaF2, 4,00 криолита. При этом из заводского состава был полностью исключен кварцевый песок и значительно сокращено количество инициатора кристаллизации стекла - криолита. Для сравнения также была изучена производственная шихта.
Ключевые слова: связующее стекло, процесс стеклообразования, стеклокристаллический материал, физико-химические свойства.
SOME ASPECTS OF THE INTERACTION OF GLASS BINDER COMPONENTS DURING HEAT TREATMENT ACCORDING TO THE GLASS PHASE CONTENT
Research article
Sidikova T.D.*
ORCID: 0000-0001-8745-6710, Tashkent State Transport University, Tashkent, Uzbekistan
* Corresponding author (taxira-dalievna[at]mail.ru)
Abstract
This article presents generalized data on the synthesis of glass-crystalline materials based on flotation wastes. Optimal structures of glass-crystalline materials and technological parameters based on the composition Kaolin-quartz sand-flotowaste of the fluorite concentrator are developed. There have been determined the physico-chemical properties of glass-crystalline materials.
This work aims to study the production of glass-crystalline material at low synthesis temperatures (not exceeding 900oC).
The binder was studied for obtaining glass crystallite of the following chemical composition (%* - Hereinafter mass content):69,00 SiO2, 7,80 M2O3, 1,56 Fe2O3, 3,65 CaO, 0,10 MgO, 0,15 BaO,12,70 Na2O, 1,70 K2O, 4,50 CaF2, 4,00 cryolite. At the same time, quartz sand was completely excluded from the factory composition and the amount of the glass crystallization initiator, cryolite, was significantly reduced. The production binder was also studied for comparison.
Keywords: glass binder, glass formation process, glass-crystalline material, physico-chemical properties.
Glass blends are a polydisperse mixture of materials of different nature. The most refractory and inertial component of this mixture is quartz sand. The interaction process between the binder's components is a multi-stage process, occurring in the solid and molten state. Solid-phase silicate formation reactions occurring at the interface accelerate with an increase in the contact surface of the component's grains, with maximum homogeneity of the mixture mass. The appearance of melt due to the melting of alkali metal silicates and formed eutectics intensifies these reactions.
The main stages of the glass formation process are silicate formation and dissolution of residual silica. The rate of these processes can be significantly increased by replacing the quartz sand with flotation waste. Flotation wastes are finely dispersed silica material formed during the concentration of fluorite ores by flotation. Flotation wastes are close to the quartz sand used to produce glass and glass-crystalline materials in terms of their main characteristics. In processing ore material, they are affected by flotation agents, which are surface-active substances. As a result, the surface of the flotation waste becomes activated. This contributes to better mixing of the binder in mixers, provides a high quality of the prepared binder and increases the cooking characteristics of glass. When replacing quartz sand with flotation wastes, a decrease in the grain size of one of the main components - quartz sand (from 0.1-0.2 to 0.01-0.02 mm) is obvious and activates the inertial component in a more active one.
This work aims to study the production of glass-crystalline material at low synthesis temperatures (not exceeding 900oC).
The binder was studied for obtaining glass crystallite of the following chemical composition (%*): 69,00 SiO2, 7,80 AhO3, 1,56 Fe2O3, 3,65 CaO, 0,10 MgO, 0,15 BaO,12,70 Na2O, 1,70 K2O, 4,50 CaF2, 4,00 cryolite. At the same time, quartz sand was completely excluded from the factory composition and the amount of the glass crystallization initiator, cryolite, was significantly reduced. The production binder was also studied for comparison.
Table 1 - ^ Material and raw material composition of experimental glasses
Binder Raw materials, kg Added to the bind, kg per 100 kg of glass
Flotowa ste Quartz sand Angren kaolin Calcini soda ash cryolite CaF2 chalk
Experimental 87,0 - 5,0 21,0 4,0 4,35 -
Production - 66,0 12,5 21,0 10,5 - 4,5
As the object of the study selected fine silica material, which is the main by-product of enrichment fluorite concentration plant [1]. The chemical composition of the flotation waste is presented (%): 76.74 SiO2, 0.22 TiO2, 5.46 Al2O3, 1.14 Fe2O3, 0.58 FeO, 4.13 CaO, 0.54 MgO, 0.38 Na2O, 1.97 K2O, 0.10 Stot, 0.09 P2O5 0.15 BaO, 5.00 CaF2, 3.48 bp. As can be seen, the waste contains up to 5% fluorite.
The fluoride compound application practice shows their great influence on glass melting processes, glass formation, and structure of finished products [2], [4]. Due to the positive effect of fluorine ions on silicate melts' physical and chemical properties, compounds are widely used for obtaining glass crystalline materials with different properties [8].
Silicate formation reaction starts at relatively low temperatures (600oC), full binding of sodium carbonate is completed at an average temperature of 800oC, according to the scheme:
n SiO2 + Na2CO3 ^ Na2O • n SiO2 + CO2
Well-known literature data show that the greatest thermodynamic stability has sodium silicates with high silica content [6].
Reactions of formation of sodium silicates with SiO2 excess are thermodynamically possible at very low temperatures (400-500oC), while reactions with an excess of alkaline component occur at elevated temperatures /2/. It should be taken into account that the initial temperature of heterogeneous reactions is influenced by many additional factors, along with the chemical composition of the binder, the degree of grinding of its components is important.
The results of thermogravimetric analysis of such a binder showed that silicate formation proceeds in the temperature range of 400-800oC.
The vitreous phase content in the amorphous-crystalline product was used as a criterion of the interaction activity of components during binder heat treatment. The task of experimental determination of the ratio of crystalline and vitreous phases in the glass-crystalline product has practical importance. Structural indices of a material depend on the ratio of these phases and, in many respects, determine its functional properties.
Several methods are known to estimate the ratio of these phases in various materials. Some of them are based on the difference in solubility or specific volumes of vitreous and crystalline phases /3, 9, 10/. X-ray analysis is also used. The results of X-ray phase analysis in the studied samples show intensive diffraction maxima corresponding to anorthite and wollastonite, which, judging by their intensity, is the prevailing crystalline phase.
A petrographic study confirms that the microstructure is heterogeneous. Among the main mass formed by glass and anorthite crystals with refractive indices ng = 1.589, np = 1.576, wollastonite grains with ng = 1.65, np = 1.63 are often found.
As can be seen from the data obtained, at the minimum processing temperature (800oC) of the binder, the amount of glass phase prevails from the total mass. While according to the diagram of the SiO2 - Na2O system, state formation of the liquid phase does not occur at this temperature. The shift of silicate formation reactions to lower temperatures is connected, firstly, with an increase of specific surface of the main refractory component of binder almost 9 times (from 526 to 4632 cm2/g). Secondly, the presence of impurities Fe2O3, FeO, CaO and MgO in the flotation wastes reduces the melting temperature of the mixture.
When heated, the melting of the binder was determined using a high-temperature microscope MNO-2 and the softening temperature of the glasses - on a differential dilatometer.
It was found that the introduction of fluorite waste instead of quartz sand leads to a decrease in the temperature at the beginning of the binder melting tb.b.m. and the beginning of its softening tb.b.s. and the temperature of the beginning of the glass softening of tb.g.s. This made it possible to implement glass boiling and crystallization at lower temperatures compared with the known composition.
Table 2 - Comparative characteristics of the melting of the charge under heating
Structure tbgs оС tb.b.m оС tb.b.m оС tb.b.s оС
Experimental 500 480 885 1010
Production 580 820 985 1070
Thus, silicate formation reactions in using flotation wastes end at lower temperatures (decrease in temperature by 100oC on average), leading to the earlier appearance of the liquid phase and further dissolution of quartz. In general, this accelerates the process of glass formation.
Thus, the possibility of using waste fluorite concentrators for the production of glass and glass-crystalline materials without changing the technological modes of production has been established. The use of flotation wastes instead of quartz sand at the Tashkent plant "Steklokristall" significantly reduced the transportation distance of raw materials and expanded t he raw material base of the glass industry.
Конфликт интересов Conflict of Interest
Не указан. None declared.
Список литературы / References
1. Sidikova T.D. Crystallization and physicochemical properties of glasses based on industrial wastes / T.D. Sidikova //Glass and ceramics. -1997. №3 - pp. 29-30.
2. Krasheninnikova N.S. The use of non-traditional raw materials in consideration of their oxidation-reduction characteristics / N.S. Krasheninnikova // Glass and ceramics. - 2003. - № 8, pp. 20-22.
3. Cao J. Sinterability, microstructure and compressive strength of porous glass-ceramics from metallurgical silicon slag and waste glass / J. Cao, J. Lu, L. Jiang, et al. // Ceramics International. 2016. 42(8). Pp. 10079-10084. DOI: 10.1016/j.ceramint.2016.03.113.
4. Chen B. Study of foam glass with high content of fly ash using calcium carbonate as foaming agent / B. Chen, K. Wang, X. Chen et al. //Mater Lett, 79 (2012), pp. 263-265.
5. Sidikova T.D. The research of crystallization properties and structure of glasses for construction based on industrial wastes / T.D. Sidikova // International research journal 1 2 (92) Part 1. February pp. 153-156.
6. Rawlings R.D. Glass-ceramics: their production from wastes-a review / R.D. Rawlings, J.P. Wu, A.R. Boccaccini // J Mater Sci, 41 (2006), pp. 733-761
7. Zhang W. A low cost route for fabrication of wollastonite glass-ceramics directly using soda-lime waste glass by reactive crystallization-sintering / W. Zhang, H. Liu // Ceram Int, 39 (2013), pp. 1943-1949
8. Арипова М.Х. Стеклокристаллические плитки для полов на основе местного сырья и отходов промышленности / М.Х. Арипова, З.А. Бабаханова, Х.П. Жуманиёзов // Universum: технические науки 2020 № 6 (75) часть 2 С.76-21
9. YuXuan Zhang. Raman spectroscopic study of irregular network in the process of glass conversionto CaO-MgO-AbO3-SiO2 glass-ceramics / YuXuan Zhang, HangRen Li, SaiYu Liu et al. // Journal of Non-Crystalline Solids (IF 2.929) PubDate : 2021-03 23, DOI: 10.1016 /j.jnoncryso l.2021.
10. Chinnam R.K. Review. Functional glasses and glass-ceramics derived from iron rich waste and combination of industrial residues / R.K. Chinnam, A.A. Francis, J. Will et al. // J. Non-Cryst. Solids, 365 (2013), pp. 63-74
Список литературы на английском языке / References in English
1. Sidikova T.D. Crystallization and physicochemical properties of glasses based on industrial wastes / T.D. Sidikova //Glass and ceramics. -1997. №3 - pp. 29-30.
2. Krasheninnikova N.S. The use of non-traditional raw materials in consideration of their oxidation-reduction characteristics / N.S. Krasheninnikova // Glass and ceramics. - 2003. - № 8, pp. 20-22.
3. Cao J. Sinterability, microstructure and compressive strength of porous glass-ceramics from metallurgical silicon slag and waste glass / J. Cao, J. Lu, L. Jiang, et al. // Ceramics International. 2016. 42(8). Pp. 10079-10084. DOI: 10.1016/j.ceramint.2016.03.113.
4. Chen B. Study of foam glass with high content of fly ash using calcium carbonate as foaming agent / B. Chen, K. Wang, X. Chen et al. //Mater Lett, 79 (2012), pp. 263-265.
5. Sidikova T.D. The research of crystallization properties and structure of glasses for construction based on industrial wastes / T.D. Sidikova // International research journal 1 2 (92) Part 1. February pp. 153-156.
6. Rawlings R.D. Glass-ceramics: their production from wastes-a review / R.D. Rawlings, J.P. Wu, A.R. Boccaccini // J Mater Sci, 41 (2006), pp. 733-761
7. Zhang W. A low cost route for fabrication of wollastonite glass-ceramics directly using soda-lime waste glass by reactive crystallization-sintering / W. Zhang, H. Liu // Ceram Int, 39 (2013), pp. 1943-1949
8. Aripova M. H. Steklokristallicheskie plitki dlja polov na osnove mestnogo syr'ja i othodov promyshlennosti [Glass-crystal tiles for floors based on local raw materials and industrial waste] / M. H. Aripova, Z. A. Babakhanova, H. P. Zhumaniezov // Universum: technical sciences 2020 No. 6 (75) part 2 p. 76-21. [in Russian]
9. YuXuan Zhang. Raman spectroscopic study of irregular network in the process of glass conversionto CaO-MgO-AbO3-SiO2 glass-ceramics / YuXuan Zhang, HangRen Li, SaiYu Liu et al. // Journal of Non-Crystalline Solids (IF 2.929) PubDate : 2021-03 23, DOI: 10.1016 /j.jnoncryso l.2021.
10. Chinnam R.K. Review. Functional glasses and glass-ceramics derived from iron rich waste and combination of industrial residues / R.K. Chinnam, A.A. Francis, J. Will et al. // J. Non-Cryst. Solids, 365 (2013), pp. 63-74
