Batch Composition Research Articles

METALLURGICAL WASTE VALORIZATION FOR FABRICATING GLASS-CERAMICS MATERIALS

The valorization of a metallurgical waste (i.e., an iron-rich slag) as raw material for the fabrication of high hardness glass-ceramics using differential thermal analysis, X-ray diffraction, X-ray fluorescence and scanning electron microscopy was investigated. The melting of the slag was aided by the addition of waste glass cullet (WGC) and the vitrification field of this system was investigated. The non-isothermal crystallization kinetics of the parent glass with the highest slag content was studied by DTA and crystallization of the parent glasses led to of pyroxenic crystalline phases, suggesting the application of the obtained glass-ceramics as building materials. Environmental benefits such as the reduction in the consumption of virgin raw materials and the elimination or reduction of CO2 and SO2 emissions due to absence of carbonates and sulphates in the batch composition make it an interesting alternative for the application of this technology.

Pb-Rich Slags, Minerals, and Pollution Resulted from a Medieval Ag-Pb Smelting and Mining Operation in the Silesian-Cracovian Region (Southern Poland)

Since the 12th century in the Silesian-Cracovian area, lead, litharge, and silver have been produced by the pyrometallurgical processing of Pb-Ag-Zn ore. Slags and soils contaminated with heavy metals (Zn, Pb, Cd, Fe, Mn, As) were the subject of this research. Samples were collected during archaeological works in the area of early medieval metallurgical settlement. The main goals of the analyses (Scanning Electron Miscroscopy-Energy Dispersive Spectroscopy (SEM-EDS), Electron Probe Microanalyzer (EPMA), X-ray diffraction (XRD), Atomic Absorption Spectroscopy (AAS)) were the determination of the mineralogical composition of furnace batches and smelting temperatures and conditions. In soils, the anthropogenic phases enriched in Pb, Zn, Fe, Mn, P, and primary minerals like goethite, ferrihydrite, sphalerite, galena, smithsonite, minrecordite, cerussite, gypsum, anglesite, jarosite, and hemimorphite were identified. The soil from former metallurgical settlements contained up to 1106 mg·kg−1 Pb, 782 mg·kg−1 Zn, 4.7 mg·kg−1 Cd in the fine fraction. Much higher heavy metal concentrations were observed in the waste products of ore rinsing, up to 49,282 mg·kg−1 Pb, 64,408 mg·kg−1 Zn, and 287 mg·kg−1 Cd. The medieval smelting industry and Pb-Ag-Zn ore processing are marked by highly anomalous geochemical pollution (Pb, Zn, Cd, Fe, Mn, Ba) in the topsoil. The methods of mineralogical investigation, such as SEM-EDS or EMPA, can be used to identify mineralogical phases formed during metallurgical processes or ore processing. Based on these methods, the characteristic primary assemblage and synthetic phases were identified in the area polluted by medieval metallurgy and mining of Pb-Ag-Zn ores, including MVT (Mississippi Valley Type) deposits. The minerals distinguished in slags and the structural features of metal-bearing aggregates allow us to conclude that batches have included mostly oxidised minerals (PbCO3, ZnCO3, CaZn(CO3)2, FeOOH), sulfides (PbS and ZnS) and quartz (SiO2). The laboratory experiment of high-temperature heating of the examined slags showed that smelting temperatures used in the second half of 13th century were very high and could have reached up to 1550 °C. The results indicate, that geochemical and mineralogical methods can be used to obtain important information from archaeological sites, even after archaeological work has long ceased.

Effect of the process conditions on the anaerobic fermentation of glucose for the production of chemicals

In the context of biorefinery for the production of chemicals, this study optimised the processes to enhance the anaerobic production of ethanol and short-chain organic acids from glucose. The optimised variables included (with a total of 49 runs) residence time (2–100 h), temperature (25–35 °C), type of inoculum (soil or anaerobic digester), presence or absence of pre-acclimation of the inoculum, glucose concentration (5–50 g/L), continuous or batch mode and composition of the mineral media (mineral solution with or without trace elements, with deionised or tap water). In continuous experiments, the residence time was the most important parameter that affected glucose conversion (over 80% glucose conversion for residence time longer than 30 h) and product yields (ethanol was the main product in the range of residence times 20–50 h, with yields in the range 0.30–0.40 g/g glucose removed). Temperature, type of inoculum, and pre-acclimation had little effect on glucose conversion and products yield. The addition of trace elements had an important beneficial effect on the removal of glucose when it was fed at the highest concentration (50 g/L) in both continuous and batch experiments. In batch runs, acetate was generally the main fermentation product rather than ethanol and ethanol conversion into acetate was favoured by nitrogen sparging, probably due to the reduced hydrogen partial pressure.

Particle Size Estimation of Powder with Refractory Additives for Plasma Surfacing

Abstract—A dynamic model of the sprayed particles with uniform distribution of the speed and temperature of the plasma flux is developed. Analytical estimates are obtained for the particle velocity in the flux—that is, the Biot number, which characterizes the heat transfer between the particles and the plasma flux—and also for the temperature distribution of the particles over time and over the radius. The fractional composition of the batch in the powder wire dispersed by argon plasma is calculated.

Nanocrystalline zeolites in supercritical water. Part B: Challenges of synthesis in organotemplate-free condition

In the second part, fast synthesis of nanocrystalline zeolites in supercritical water (SCW) condition is studied in the absence of hazardous organic templates with a main product of analcime. The reason is attributed to the reduction in ion dissociation in SCW. In order to reach higher ion dissociation and therefore increase the chance to obtain other type of zeolites, first the alkalinity atmosphere of precursor batch composition changed from sodium hydroxide to potassium hydroxide in SCW followed by adding a long-chain alcohol (namely 2-decanol) in order to add the concentration of OH− in synthesis system. The addition of 2-decanol shows a noteworthy modification in the size and size distribution of nanocrystals as well as product yield. This method is green and promising for the rapid synthesis of zeolitic nanoparticles in uniform size with a high degree of purity and crystallinity as well.

A phase equilibrium investigation of selected source controls on the composition of melt batches generated by sequential melting of an average metapelite

Abstract The ability of Rcrust software to conduct path-dependent phase equilibrium modelling with automated changing bulk compositions allows for a phase equilibrium approach to investigate an array of source controls for their effect on the bulk compositions of melts produced by sequential melting events. The following source controls of the rock system are considered: (1) initial magnesium and iron content; (2) initial sodium and calcium content; (3) pressure–temperature path followed by the system; and (4) threshold by which melt extractions in the system are triggered. These source controls are investigated in a water-restricted system and a water-in-excess system. The permutation of these cases resulted in 128 different modelled pressure–temperature bulk composition paths investigating the melting of an average pelite composition. The resultant melt compositions are compared to that of a natural granite dataset and provide a good fit for the incompatible elements Na 2 O and K 2 O with the allowance that granites most likely form as magmas consisting of melt and ferromagnesian-rich crystals. The fluid state of the system is shown to have the strongest control on melt compositions, with the pressure–temperature path having subordinate control on the volume and composition of melts produced.

Evidence for a Correlation of Melt Fragility Index With Topological Phases of Multicomponent Glasses

Scores of glass compositions in the equimolar GexAsxSe100-2x ternary system are synthesized across the 0 Ge, in Ge content ‘x’, across a 2-gram sized batch composition of less than 0.01% was realized. We undertook Modulated-DSC, Raman scattering and molar volume experiments as a function of composition. Trends in Tg(x) increase monotonically with x over the examined range, but the non-reversing enthalpy of relaxation at Tg, ΔHnr(x), displays a sharp square-well like reversibility window over the 9.5(2)% 20 outside that range, thus establishing a fragility window. The close correlation between the variations of m(x) and ΔHnr(x) underscores that super-strong melts formed in the fragility window form Intermediate Phase (IP) glasses in the reversibility window, while fragile melts formed at non-IP compositions give rise to either flexible or stressed-rigid glasses. Molar volumes of glasses reveal a global reduction for IP glass compositions, thereby underscoring the compacted nature of the isostatically rigid networks formed in that phase. Evidence for specific dynamic features of the different phases is provided by molecular dynamics simulations, which indicate that the diffusivity is minuscule for x >17% and increases substantially in the flexible phase. These results show that liquid dynamics and fragility encode glass topological phases in this ternary chalcogenide. The optimization of the glass-forming tendency for IP compositions, the stress-free nature of these networks, and the qualitative suppression of aging, are features that all point to their ideal nature. These ideas of IP glasses as ideal glasses are at variance with the notion that ideal glasses possess a low configurational entropy and form at Tg values that approach the Kauzmann temperature. IP networks display, adaptability, high glass-forming tendency, stress-free nature and high configurational entropy of networks.

Determining the continuous thermo-optic coefficients of chalcogenide glass thin films in the MIR region using FTIR transmission spectra.

A new method (FTIR continuous dn / dT method, n is refractive index and T temperature) for measuring the continuous thermo-optic coefficients of thin transparent films in the mid-infrared (MIR) spectral region is introduced. The technique is based on Fourier transform infrared (FTIR) transmission spectra measured at different temperatures. It is shown that this method can successfully determine the thermo-optic coefficient of chalcogenide glass thin films (of batch compositions Ge20Sb10Se70 at. % (atomic %) and Ge16As24Se15.5Te44.5 at. %) over the wavelength range from 2 to 25 µm. The measurement precision error is less than ± 11.5 ppm / °C over the wavelength range from 6 to 20 µm. The precision is much better than that provided by the prism minimum deviation method or an improved Swanepoel method.

Effect of mixing on the properties of nanocarbon containing Al2O3‐C continuous casting refractories

AbstractThe functional refractories used in steel casting operations are usually made up of alumina‐carbon compositions having graphite as the major source of carbon. In recent times, to reduce the carbon content and to enhance the performance by designing microstructure at nano‐sized level, several nano carbon sources and organic binders are introduced to traditional carbon‐based refractories. The homogenous distribution of nano carbon sources within the refractory composition is important to get the advantages of its use. In the present work, nanocarbon black is used along with graphite in the alumina‐carbon system. Three different mixing procedures are followed and how mixing effects the physical and mechanical properties is evaluated. The mixing order with proper nanocarbon distribution throughout the batch composition provided significant improvement in the properties. The microstructural analysis and in situ phase developments in the samples at different temperatures are also studied.

Production and Characterization of Alumina and Steatite Based Ceramic Insulators

In this study, production of alumina and steatite containing ceramic insulators as thermostat material was realized by investigating the composition, pressing pressure and sintering temperature. 90 bar of pressing pressure was employed to give a ring shape to thermostat insulators by mixing with 3% kerosene. Alumina based samples were sintered at 1400°C, while 1300°C sintering temperature was determined to be efficient for steatite based samples. Optimum pressing pressure and sintering temperature for batches were 90 bar and 1350°C, respectively. Sintered bodies subjected to Megger test at 1200 V and 50 Hz exhibited good electrical insulation. It was concluded that higher alumina containing batch composition was the ultimate candidate as thermostat insulator, especially in terms of density and compressive strength.

Development of Self-Glazing Ceramic Facing Material Based on Low-Plasticity Clay

A batch composition for facing ceramic based on low-plasticity clay with an additive containing boric acid and lithium carbonate as fluxes as well as titanium dioxide as a strengthening additive was developed. The influence of the additives on the formation of the structure, composition, and basic operational properties of the obtained ceramic was investigated. It is shown that it is possible to produce a ceramic material possessing the property of self-glazing of the surface of articles and meeting the requirements of articles for the facing of the socles of buildings and structures.

Ionic conductivity behavior by activated hopping conductivity (AHC) of barium aluminoborosilicate glass–ceramic system designed for SOFC sealing

Non-conducting BaO-B2O3-Al2O3-SiO2 parent glasses designed for solid oxide fuel cell (SOFC) sealing applications were prepared using the melt-quenching technique. The glass formation region was determined according to phase equilibrium relations and was found to be in the composition range 70BaO-(x)Al2O3-(10−x)B2O3-20SiO2 where 3.0 < x < 6.0 wt%. The conductivity values obtained conductivity ranged from 10−5 to 10−10 S/cm at temperatures between 600 and 850 °C. The batch compositions presented a threshold of dc conductivity near 70BaO wt% with a quasi linear behavior with the decrease of the BaO content. Different values of conduction activation energy were observed at temperatures above the glass transition temperature (Tg) (up to 700 °C), which were attributed to the thermal bond-breaking of non-bridging oxygen (NBO) defects. The experimental results of the electrochemical characterization by impedance spectroscopy of glass–ceramic interfaces with yttria-stabilized zirconia (YSZ) acting as solid ionic conductor electrolyte are presented and discussed.

Decision-Making Support in Blast-Furnace Operation

A model system for decision-making support (a model of the blast-furnace process developed at Yeltsin Ural Federal University and PAO MMK) is considered. The basic model modules permit calculation of the material and thermal balances, simulation of the thermal, slag, and gas-dynamic conditions in the blast furnace, and selection of the batch composition. The model system, embodied as software, is integrated into the PAO MMK information system. The model for calculating the material and thermal balances permits determination of the Fe, S, Mn, and Ti balances. Introduction of the Slag Conditions software permits identification of the most important slag property to ensure normal slag conditions; determination of the ratio of the iron-ore materials so that the slag has the best viscosity and viscosity gradient; and the production of hot metal of the required quality. The introduction of Blast-Furnace Gas Dynamics software permits calculation and visual mapping of the gas-dynamic characteristics of the batch bed and assessment of the change in pressure difference and equilibration of the batch within individual zones of the furnace in the design period, with variation in the batch parameters and properties. The results obtained in practical use of this system are outlined. Recommendations are made regarding the solution of industrial problems.

Structural Modification of Ceramic Brick with Multi-Walled Carbon Nanotubes

The paper considers a method for improving physical and mechanical properties of ceramic bricks made from low-melting low-grade clay and quartz sand. The priority task is to develop a kind of batch based on widespread low-grade clay containing less than 13.5% of Al2O3. This provides high physical, technical and operational characteristics of brick. To improve the properties of ceramic building materials, multi-walled carbon nanotubes (MWCNTs) can be used as an effective structural modifier in an amount of 0.001-0.009% of the clay mass. Adding an aqueous dispersion of MWCNTs to the composition of ceramic batch increases the density and uniformity of the structure of ceramic matrix and influences its strength characteristics. The increase in the strength indices of ceramic has been found to occur in both cases of using freshly prepared batch and batch seasoned for a long time, up to 6 months. Nanotubes already influence the strength of the samples at the stage of air brick forming, while the compressive strength increases by 50%. After firing, the compressive strength of fired modified samples increases by 109%. Thus, using an aqueous dispersion of MWCNTs improves the structure and physical and mechanical properties of ceramic brick.

Optimal Fractional Composition of Batch for Synthesis of Foam-Glass Materials Based on Diatomite from the Chernoyarskoe Deposit

The types and function of foam glass are examined as a function of the employed foaming agents. Mixes with different granulometric composition of the batch were developed and subjected to heat-treatment. The influence of the fractional composition of the foam-glass batch on the density and volume of the foam glass and foam-glass materials was studied.

Environmental and economic damage from the dust waste formation in the silicon production

In this paper, we presented the results of the silicon production dust waste studies. We also estimated the expected efficiency and, as a result of its calculation, the reduction in fees for the disposal of man-made raw materials of hazard class 4 at Kremny CJSC, when used in the composition of the gas cleaning dust batch, could reach 743,772.17 rubles/year. The paper substantiates the necessity to use the method of batch material pelletizing based on man-made raw materials.

Mogući matematički odnos između uticaja odnosa (Si/Al) i (Ca/Si) na pritisnu čvrstoću uzorka jalovine dobijene iz rude gvožđa nastalu prilikom geopolimerne reakcije

In geopolymer reactions, with lime rich compound addition, the strength parameter is dependent on the molar ratios of (Si/Al) and (Ca/Si), such that (Si/Al) ratio contributes to short period and (Ca/Si) ratio contributes to long period strength development. In the present study a mathematical model has been proposed to identify the role of each on compressive strength development through exponential mathematical relationship, such that, N1 is an exponent of (Si/Al) ratio and N2 is an exponent of (Ca/Si) ratio indicating short period and long period strength development parameter respectively, while C is the compressive strength developed on keeping the samples for different extended time periods. The values of N1 and N2 can be found out by solving linear equations relating (Si/Al) ratio, (Ca/Si) ratio, and compressive strength values of different experimental batch compositions. Calculated and selected additions of sodium silicate, sodium hydroxide, lime and GGBS in iron ore mine tailing samples indicated that the values of N1 and N2 merged with each other after 7 days reaction period, but after 28 days reaction line due to N1 is found above that of N2. It is concluded that for long period strength development (Si/Al) ratio is more important in comparison to (Ca/Si) ratio.

Acrocomia crispa fruits lipid extract prevents LPS-induced acute lung injury in mice

The aim of this study was to evaluate the effects of single oral doses of D-005 (a lipid extract obtained from the fruit oil of Acrocomia crispa) on LPS-induced acute lung injury (ALI) in mice. D-005 batch composition was: lauric (35.8%), oleic (28.4%), myristic (14.2%), palmitic (8.9%), stearic (3.3%), capric (1.9%), caprylic (1.2%), and palmitoleic (0.05%) acids, for a total content of fatty acids of 93.7%. D-005 (200 mg/kg) significantly reduced lung edema (LE) (≈ 28% inhibition) and Lung Weight/Body Weight ratio (LW/BW) (75.8% inhibition). D-005 (25, 50, 100 and 200 mg/kg) produced a significant reduction of Histological score (59.9, 56.1, 53.5 and 73.3% inhibition, respectively). Dexamethasone, as the reference drug, was effective in this experimental model. In conclusion, pretreatment with single oral doses of D-005 significantly prevented the LPS-induced ALI in mice.

Managing oil properties in order to optimise power consumption in trunk pipelines

ORGANISATIONAL ARRANGEMENTS TO maximise energy efficiency are traditionally afforded a great deal of attention in pipeline oil transportation. Nonetheless, as has been shown by benchmark studies conducted by the International Association of Oil Transporters, there are still significant areas of improvement for lowering energy use. One promising area involves managing the flow properties of the fluids being pumped. There are some widely known technological solutions for pumping oil with diluting agents or by heating, or using anti-turbulent or depressor additives. However, significantly less consideration is given to possibilities for optimising the compositional blend of crude oils. These blends can be formed from a range of products from different suppliers, either at main pumping stations, or during line boosting at “tie-ins” in trunk pipelines.Forming commercial batches from a blend of crude oils shows promise as a logistical and technical measure. It would require its own methodological basis in order to produce solutions using effective algorithms to manage the technological process of pumping.This article presents methodological approaches to achieving the aim of optimising the composition of crude oil batches, according to the criterion of the minimum unit energy costs for pumping. It also evaluates how sensitive power consumption is to changes in viscosity, given various oil flow parameters in the pipelines, and provides a rationale for the conditions necessary to achieve a positive operational effect. In this research, an algorithm was developed for finding optimum concentration values for batches being prepared for transport, based on analysis of a viscosity isotherm for a binary mixture of oils.This study uses the example of calculating various options for forming binary mixtures from crude stock at delivery and acceptance points of the first process section of the Usa - Ukhta trunk pipeline, in order to demonstrate the option to reduce energy consumption by 4.5%, provided planned targets are met unconditionally.

Highly porous granulated corundum aggregate prepared out of alumina-polystyrene-foam mixture. Part 9. Physical and technical properties of the porous corundum pellets and of the pellets-based filling materials

The investigating results are given for the strength capabilities of both the separate fractions and the fraction-based mixtures. It was established that to decrease the flling materials' heat conductivity the diameter of the pellets should be reduced or the density of the poly-disperse composition should be increased. The introducing of the corundum flling with grain size of not more than 60 micrometers into the batch's composition raises the pellets' thermal stability.Ill.5. Tab. 3.