scholarly journals Research into the chemical composition of refinery slag from silicon production for its efficient recycling

2021 ◽  
Vol 25 (2) ◽  
pp. 252-263
Author(s):  
N. V. Nemchinova ◽  
V. V. Hoang ◽  
I. I. Aponchuk
Keyword(s):  
Chemical Composition ◽  
Crystalline Silicon ◽  
Raw Material ◽  
Smelting Process ◽  
Elemental Silicon ◽  
Silicon Production ◽  
X Ray ◽  
Industrial Material ◽  
Furnace Slag ◽  
Oxidation Refining

The aim was to investigate the chemical composition of refinery slag obtained during silicon production in order to identify approaches to its further recycling. Research samples were collected from the slag remained after oxidation refining at the JSC Silicon (AO Kremny), RUSAL (Shelekhov, Irkutsk Oblast). The methods of X-ray phase, X-ray fluorescence, metallographic and scanning electron microscopy were employed to investigate the chemical composition of the samples. It was found that the refinery slag under study includes such basic components as elemental silicon, its carbide and oxide, as well as elemental carbon. It was shown that silicon carbide is the product of incomplete reduction, resulting from melting silica-containing ores in a smelting furnace. According to the conducted X-ray fluorescent analysis, the samples also contain (wt %): Ca - 7.40; Al - 3.80; Fe - 0.30; Ba - 0.19; K - 0.14; Na - 0.09; Sr - 0.09; Mg - 0.08; Ti - 0.05; S - 0.02. Calcium and aluminium are present in the slag mostly in the form of oxides. Complex oxides of an anor-thite type were also found: CaO Al2O3 2SiO2. The refinery slag under study also features insignificant amounts of other metal oxides, which are released from the furnace slag forming during the smelting process. The slag produced by oxidation refining during crystalline silicon production is a technogenic raw material containing valuable components. Due to the significant content of silicon in the refinery slag (from 42% to 65%), the existing methods applied to recycle such an industrial material were analysed in terms of additional silicon extraction or production of commercial silicon-containing products, which are in demand in various industries.

Mathematical Modeling оf the Silicon Production Process from Pelletized Charge

2020 ◽  
Vol 989 ◽  
pp. 394-399
Author(s):  
Nina V. Nemchinova ◽  
Andrey A. Tyutrin ◽  
Sergei N. Fedorov
Keyword(s):  
Chemical Composition ◽  
Crystalline Silicon ◽  
Raw Materials ◽  
Smelting Process ◽  
Aluminum Production ◽  
Molten Silicon ◽  
Product Modeling ◽  
Silicon Phase ◽  
Silicon Production ◽  
Metallurgical Silicon

The paper considers the problem of recycling the dust waste resulting from metallurgical silicon production; such dust contains considerable amounts of valuable silica. The problem is solved by redirecting this byproduct to the silicon smelting process. We herein propose using the dust left in silicon and aluminum production as a component of pelletized charge, used for silicon smelting in ore-thermal furnaces (OTF). Mathematical (physico-chemical) modeling was applied to study the behavior of pelletized-charge components, in order to predict the chemical composition of smelting-produced silicon. We generated a model that simulated the four temperature zones of a furnace, as well as the crystalline-silicon phase (25°С). The model contained 17 elements entering the furnace, due to being contained in raw materials, electrodes, and the air. Modeling produced molten silicon, 91.73 wt% of which was the target product. Modeling showed that, when using the proposed combined charge, silicon extraction factor would amount to 69.25%, which agrees well with practical data. Results of modeling the chemical composition of crystalline silicon agreed well with the chemical analysis of actually produced silicon.

scholarly journals Geochemistry and Mineralogy of Ice-Dammed Lake Sediments of the Lębork Deposit

2021 ◽  
Author(s):  
Radosław Rogoziński ◽  
Alina Maciejewska
Keyword(s):  
Chemical Composition ◽  
Lake Sediments ◽  
Inductively Coupled Plasma ◽  
Mineralogical Composition ◽  
Raw Material ◽  
Element Analysis ◽  
X Ray ◽  
Dominant Component ◽  
Clay Deposits ◽  
Dammed Lake

AbstractVarved clay deposits from ice-dammed lakes are a particularly important and broadly applied raw material used for the production of high-quality ceramics (red bricks, roof tiles, etc.), but the mineralogy and geochemistry of these sediments are not fully understood. The aim of the present study was to determine the chemical and mineralogical composition of ice-dammed lake sediments of the Lębork deposit. Major-element analysis of the compositions of selected samples from the ice-dammed lake clays was performed by X-ray fluorescence (XRF) and trace elements were determined by inductively coupled plasma-mass spectrometry. The mineralogical composition of clay samples was determined by X-ray diffraction (XRD). Analyses of the chemical composition of the ice-dammed lake clays of the Lębork deposit showed that the dominant component was SiO2 with a mean content of 56.13 wt.%; the second most abundant component was Al2O3, with a mean content for the entire deposit of 11.61 wt.%. Analysis by ICP-MS indicated the presence of rare earth elements (REE), e.g. cerium, neodymium, lanthanum, and praseodymium; their mean contents are: 56.9, 27.0, 26.3, and 7.3 ppm, respectively. Mineralogical analysis of the varved clays identified quartz, muscovite, calcite, and clay minerals – illite, kaolinite, and montmorillonite. The material filling the Lębork basin is characterized by small lateral and vertical variability in chemical composition. The results of the present study may be of considerable importance in determining the parent igneous, metamorphic, and sedimentary rocks, the weathering products of which supplied material to the ice-dammed lake, as well as in determining the mechanisms and character of the sedimentation process itself.

The Research of Iron Containing Wastes Modification Process of Leninabad Rare Metals Plant

2021 ◽  
Vol 410 ◽  
pp. 778-783
Author(s):  
Pavel V. Matyukhin ◽  
Daler I. Mirzoev
Keyword(s):  
Chemical Composition ◽  
Building Materials ◽  
Raw Material ◽  
Filling Material ◽  
Rare Metals ◽  
X Ray ◽  
Modification Process ◽  
Before And After ◽  
The Republic ◽  
Enrichment Process

The paper presents the results of ferriferous wastes modification process research carried on the basis of JCS “Leninobad rare metals Plant” located in the Republic of Tajikistan. The wastes for the study were taken from the western tailing. The article presents the justification of the chosen wastes as a filling material in the development of new radiation protective composite building materials. The data on the initial ferriferous chemical composition of the tailing wastes and the chemical composition of the material that passed the enrichment process is presented. The study contains microphotos of ferriferous haematite raw material particles surface before and after completing the modifying process. The paper presents and describes the study of X-ray phase analysis diffractograms of enriched iron-containing wastes before and after the modification process. The current research proves that the enrichment ferriferous wastes particles modification process is possible and as a result it can be used as a filling for the development of new kinds of radioprotective composite materials.

scholarly journals The Effects of Temperature on the Hydrothermal Synthesis of Hydroxyapatite-Zeolite Using Blast Furnace Slag

Materials ◽  
2019 ◽  
Vol 12 (13) ◽  
pp. 2131 ◽  
Author(s):  
G.U. Ryu ◽  
G.M. Kim ◽  
Hammad R. Khalid ◽  
H.K. Lee
Keyword(s):  
Blast Furnace ◽  
Hydrothermal Synthesis ◽  
Blast Furnace Slag ◽  
Raw Material ◽  
X Ray Diffraction ◽  
X Ray ◽  
Different Temperatures ◽  
Type Zeolite ◽  
Effects Of Temperature ◽  
Furnace Slag

Blast furnace slag, an industrial by-product, is emerging as a potential raw material to synthesize hydroxyapatite and zeolite. In this study, the effects of temperature on the hydrothermal synthesis of hydroxyapatite-zeolite from blast furnace slag were investigated. Specimens were synthesized at different temperatures (room temperature, 50, 90, 120, or 150 °C). The synthesized specimens were analyzed qualitatively and quantitatively via X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), BET/BJH, and scanning electron microscopy/energy dispersive using X-ray analysis (SEM/EDX). It was found that the hydroxyapatite phase was synthesized at all the reaction temperatures, while faujasite type zeolite appeared in the specimens synthesized at 90 and 120 °C. Moreover, faujasite was replaced by hydroxysodalite in the specimens synthesized at 150 °C. Additionally, the crystals of the hydroxyapatite tended to become larger and total crystallinity increased as the reaction temperature increased.

Microanalytical studies (X-ray photoelectron spectrometry) of surface hydration reactions of cement compounds

1983 ◽  
Vol 310 (1511) ◽  
pp. 85-92 ◽  
Keyword(s):  
Blast Furnace ◽  
Chemical Composition ◽  
Kinetic Energy ◽  
Blast Furnace Slag ◽  
X Rays ◽  
Hydration Time ◽  
X Ray ◽  
Tentative Interpretation ◽  
Furnace Slag ◽  
Cement Compounds

X-ray photoelectron spectrometry (X.p.s.) measures the kinetic energy of electrons photoejected from a solid surface by soft X-rays. The kinetic energy of the photoelectrons can be related to the binding energy that these electrons had originally in the solid. X.p.s. is a rather new technique for studying cements. It has been used recently in the surface analysis of C 3 S, C 2 S, C 3 A and blast-furnace slag grains during their hydration. Changes in chemical composition have been found as soon as the surface comes into contact with water, shown by a change in the shape, position an intensity of characteristic peaks like Ca 2p , Si 2p , O l8 and a reduction of characteristic ratios Ca/Si or Al/Si. A tentative interpretation of X.p.s. kinetic curves as a function of hydration time is presented.

scholarly journals Mathematical Modelling to Control the Chemical Composition of Blast Furnace Slag Using Artificial Neural Networks and Empirical Correlation

2021 ◽  
Vol 1203 (3) ◽  
pp. 032096
Author(s):  
Wandercleiton Cardoso ◽  
Danielle Barros ◽  
Raphael Baptista ◽  
Renzo di Felice
Keyword(s):  
Blast Furnace ◽  
Chemical Composition ◽  
Blast Furnace Slag ◽  
Raw Materials ◽  
Raw Material ◽  
Operational Parameters ◽  
Materials Research ◽  
Artificial Neural ◽  
Furnace Slag ◽  
Alkali Activated

Abstract Portland cement additions have been used for many years with the main objective of reducing the amount of clinker. Among the additions, blast furnace slag, resulting from the production of pig iron, that is, reusing this by-product, reduces the emission of carbon dioxide as well as decreases the exploitation of natural limestone and clay reserves, which are raw materials for Portland clinker. In order to reduce these emissions and increase the availability of raw materials, research has been directed to study clinker-free binders, as is the case with activated alkali cements and supersulfated cements. In this way, alkali-activated cements can only involve the reuse of industry by-products and do not require the calcination of the raw material, thus reducing the emission of polluting gases into the atmosphere. Supersulfated cement are composed of up to 90% blast furnace slag, in addition to 10 to 20% calcium sulfate. One of the most important characteristics of blast furnace slag is the ratio of the content of CaO and SiO2, also known as the simplified basicity index (B2). This paper proposes the mathematical modeling of an artificial neural network to predict the final chemical composition of the blast furnace slag to be produced based on the operational parameters of the blast furnace aiming its use in the production of special cements such as alkali-activated cements and supersulfated cements. The high values of (R) associated with low values (RMSE) show the good statistical performance of ANN demonstrating that the mathematical model is efficient to carry out the forecast of the production of blast furnace slag.

Analysis of the Composition and Properties of the Silicon Production Wet Cleaning Sludge to Identify Sustainable Techniques for its Processing

2021 ◽  
Vol 316 ◽  
pp. 649-654
Author(s):  
Andrey A. Tyutrin ◽  
Andrey S. Vologin
Keyword(s):  
Grain Size ◽  
Test Sample ◽  
Raw Material ◽  
Metallurgical Grade Silicon ◽  
Cleaning Product ◽  
Silicon Production ◽  
X Ray ◽  
Grade Silicon ◽  
Processing Techniques ◽  
Silicon Based

The paper is devoted to the urgent issue of processing the dust waste of metallurgical-grade silicon production, i.e. wet cleaning sludge, which contains a significant amount of valuable silica. The paper analyzes the formation of finely dispersed techno-genic materials that are generated in significant quantities (up to 120 t/d) at the Kremniy JSC. The composition and properties of the silicon production wet cleaning product have been studied. In analytical studies of the wet cleaning sludge samples, the modern certified analysis techniques have been used: laser diffraction, X-ray diffraction, and X-ray fluorescence. According to the analysis, the L:S ratio of liquid sludge is 2.1:1; after dehydration, the sludge cake has a grain size of 150 μm, with the prevailing (90 %) grain size of 59.65 μm in the test sample. The chemical composition of the sludge is 95.86 % SiO2; therefore, the wet cleaning sludge is a valuable raw material to produce metallurgical-grade silicon. Based on the analysis of the composition and properties of the silicon production wet cleaning sludge sample, we have developed a program for its processing. Sustainable sludge processing techniques are aimed at obtaining a briquetted charge, which can be used as an additive to the main raw material.

scholarly journals Study of the chemical composition of Amir Wali coins by x-ray fluorescent analysis

2021 ◽  
Vol 4 (5) ◽  
pp. 1238-1249
Author(s):  
Alexey N. Alyoshin
Keyword(s):  
Trace Elements ◽  
Chemical Composition ◽  
Raw Material ◽  
Basic Composition ◽  
X Ray ◽  
Fluorescent Analysis ◽  
Quantitative Content ◽  
The City

The chemical composition of seven coins of Amir Wali of six dirhams par value (two types) minted in Astarabad in 769 and 75 Hijri (1368 and 1374 AD) was studied by x-ray fluorescent analysis using a portable TRACER 5i spectrometer. There were established the basic composition of the coin alloy and the quantitative content of the trace elements. The performed comparison with the coin alloys compositions of the preceding dynasties demonstrated continuity of minting technologies and similarity of ore sources used in the production of dirhams during the reign of Amir Wali in Astarabad. Based on the literary data of galenic ores composition mined in the Zenjan province, it is suggested that the raw material for coin mintage was extracted from a deposit located near the city of Damgan.

scholarly journals Study on the Preparation and Hydration Properties of a New Cementitious Material for Tailings Discharge

Processes ◽  
2019 ◽  
Vol 7 (1) ◽  
pp. 47 ◽  
Author(s):  
Yunbing Hou ◽  
Pengchu Ding ◽  
Dong Han ◽  
Xing Zhang ◽  
Shuxiong Cao
Keyword(s):  
Pore Size ◽  
Raw Material ◽  
Curing Time ◽  
Hydration Products ◽  
X Ray Diffraction ◽  
Hydration Properties ◽  
Crystalline Phases ◽  
X Ray ◽  
Mercury Intrusion ◽  
Furnace Slag

Blast furnace slag (BFS) is often used as a cement-based raw material for underground filling and surface cemented paste discharge of tailings during mining processes. This paper studied a new cement-based material (NCM) with BFS to replace ordinary Portland cement (OPC). A uniaxial compressive strength (UCS) experiment was used to test the mechanical strength of samples; X-ray diffraction and thermal gravity experiments were used to test the crystalline phases and amount of hydration products by samples; a scanning electron microscope experiment was used to observe the influence of the hydration products morphology by samples; mercury intrusion porosimetry experiment was used to analyze the pore size distribution of samples. The samples with NCM had an optimum UCS; the crystalline phases of the hydration products were similar in OPC and NCM. However, the amount of product formed in OPC was less than that in NCM at the same curing time; more ettringite and calcium silicate hydrate were produced in samples with NCM, which filled the pores and enhanced the UCS of the samples. The final mercury intrusion volume of the samples with NCM were lower than the samples with OPC at the same curing time, which showed that samples with NCM had lower porosities. For the samples with NCM and OPC cured from 7 days to 28 days, the mercury intrusion volume was reduced by 18% and 13%, and the most common pore size of the samples reduced by 53% and 29%, respectively. This showed after 21 days curing time, the pores of all the samples getting smaller; however, the samples with NCM were more compact. The main ingredients of the NCM were clinker, lime, gypsum and BFS, and its ratio was 14:6:10:70. The content of additives to NCM was 0.4%, and the ratio of sodium sulfate: alum: sodium fluorosilicate was 2:1:1.

scholarly journals Utilization of Several Industrial Wastes as Raw Material for Calcium Sulfoaluminate Cement

Materials ◽  
2019 ◽  
Vol 12 (20) ◽  
pp. 3319 ◽  
Author(s):  
Phongthorn Julphunthong ◽  
Panuwat Joyklad
Keyword(s):  
Phase Composition ◽  
Chemical Composition ◽  
Raw Materials ◽  
Industrial Wastes ◽  
Raw Material ◽  
X Ray ◽  
Calcium Sulfoaluminate ◽  
Calcination Temperatures ◽  
Setting Times ◽  
Marble Dust

The aim of this research was to study the production of calcium sulfoaluminate (CSA) cement from several industrial waste materials including with marble dust waste, flue gas desulfurization gypsum, ceramics dust waste, and napier grass ash. The chemical composition, microstructure, and phase composition of raw materials were examined using energy dispersive X-ray fluorescence (EDXRF), scanning electron microscopy (SEM), and X-ray diffraction (XRD), respectively. All raw wastes were analyzed using their chemical composition to assign proportion for raw mixture. The raw mixture is calcined at controlled calcination temperatures ranging from 1200 °C to 1300 °C for 30 min. Subsequently, with analysis, their phase composition is calculated by the Rietveld refinement technique. The results suggested that phase composition of clinker calcined at 1250 °C shows the closest composition when compared to target phases, and was selected to prepare CSA cement. The FTIR analysis was performed to study the hydration processes of CSA cement. The Ordinary Portland cement (OPC) based with adding CSA cement between 20 wt.% and 40 wt.% were investigated for the effect of CSA cement fraction on water requirement, setting times and compressive strength. The results showed that rapid setting and high early strength can be achieved by the addition of 20–40 wt.% CSA cement to OPC.

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