Low grade iron ores are often contaminated with relatively high percentage of different
impurity gangue minerals. The iron ores contaminated with manganese oxide and silica are hardly reducible
and consume more energy in the integrated steel plant. Therefore it is important to estimate and predict the
influence of manganese oxide, silica and temperature on the reduction yield of iron oxide using mathematical
model approach. In the current study, a 23
(three-parameters, two-levels)factorial design is applied on the
gaseous reduction experimental data of mixed oxides (Fe2O3-MnO2-SiO2) to build a linear regression model.
The calculations have been performed using Matlab program. The developed mathematical model indicated that
SiO2 and temperature have positive effect on the reduction yield of iron oxide. On the other hand, MnO2
exhibited the highest negative impact on the reduction yield of iron oxide followed by the interaction coefficient
of MnO2, SiO2 and temperature. The results of the developed mathematical model are fitted to the experimental
reduction data of mixed oxides.
Steel industry can be characterized by a significant amount of by-products
including fine dust (up to 1.5% of heat size). Dust of gas cleaners, containing above
0.5% Zn and 50% Fe, cannot be directly returned to basic melting facilities due to high
contents of zinc that destroys its lining. High consumption of reducing agent, furnace
lining corrosion, final product of high impurities content made difficult use of
hydrometallurgical processing. Use of hydrometallurgy technologies is held back by
zinc in dust, primarily, as ferrites that cannot be opened using alkali, while acids make
iron transfer into solution. As a result, major part of smelters stockpiles the dust.
Secondary deposits of zinc-containing steelmaking dust can be involved into processing
thus expand the feedstock of zinc industry, increase efficiency of steel making and
reduce negative impact on environment.
The paper contains chemical and mineralogical analysis of steel dust sample from
PAO Severstal and study results on hydrometallurgical extraction of zinc from dust
using salt solution. It has been established that ammonium chloride leaching of zinc
Ferrosilicon productiion and submerged arc furnace (1)Nasser Harby
Ferroalloys, by definition, are alloys of two or more metals, of which one is Iron. The U.S. Bureau of Mines defines ferroalloy as an alloy of iron with at least one other element except for carbon.
The main indicator of the quality of a ferroalloy is its chemical composition and, above all, the content of the leading element. It is important to have Consistency in alloying element amounts in ferroalloys from heat to heat, allowing the manufacture of standard products
The smelting of ferroalloys is commonly performed in electric arc furnaces.
Although ferromanganese can be produced in a blast furnace in a manner similar to iron, the reduction of chromium and silicon from their oxides requires higher Process temperatures and lower oxygen potentials than can be achieved in a blast furnace
Raw materials are perhaps the most important factor for obtaining good furnace operation the first step towards improvements is to reduce the variations
The aim of this course is to present the basic principles for the production of ferrosilicon alloys processes, and a simple preview for submerged arc furnaces.
It is attended for Engineers working in this field, and students or metallurgists maybe find answers for their questions, because at the end of this course you will figure out that you have a preview for this manufacture and the main problems and solutions for the ferrosilicon production process. And having an overview for submerged arc furnaces design and operations.
.
IJERA (International journal of Engineering Research and Applications) is International online, ... peer reviewed journal. For more detail or submit your article, please visit www.ijera.com
ANALYTICAL TOOL FOR ANALYSING SLAGGING CHARACTERISTIC OF HIGH ASH COALS IN UT...IAEME Publication
In today’s competitive market, the performance of electric utility industry is a
serious concern to the nation. Majority of power plants are Coal-Fired Power plants
in India. Due to the wide variation in the quality of coal being fired, it affects the
performance of the power plant like furnace wall slagging, convective pass slagging
(both Low and High Temperature), soot blower effectiveness, erosion and
grindability. At this juncture, a reliable prediction is needed to assess the slagging
problem which in turn affects the performance parameters of power plant like heat
transfer rate, exit gas temperature, surface corrosion and frequency of soot blowing.
Though conventional indices and ash fusion temperature measurement techniques
do not aid in predicting slagging condition with field performance hence, it is reported
to be highly subjective in nature and poor accuracy.
In this work an alternative approach is made based on shrinkage measurement up
to 1400 °C of coal ash prepared at 800 °C. Sensitive shrinkage measurements indicate
temperatures of rapid change which correspond to the formation of liquid phases.
A preliminary evaluation of shrinkage data for coal ash collected at different
power stations firing wide variety of coal indicates that, the shrinkage profiles of the
ashes are differing widely and rate of shrinkage measurement can provide an
alternative approach to characterize/assess the slagging potential. Shrinkage
measurement of coal ash has been carried out for the coal ashes collected at different
power stations using different quality of coal
Steel industry can be characterized by a significant amount of by-products
including fine dust (up to 1.5% of heat size). Dust of gas cleaners, containing above
0.5% Zn and 50% Fe, cannot be directly returned to basic melting facilities due to high
contents of zinc that destroys its lining. High consumption of reducing agent, furnace
lining corrosion, final product of high impurities content made difficult use of
hydrometallurgical processing. Use of hydrometallurgy technologies is held back by
zinc in dust, primarily, as ferrites that cannot be opened using alkali, while acids make
iron transfer into solution. As a result, major part of smelters stockpiles the dust.
Secondary deposits of zinc-containing steelmaking dust can be involved into processing
thus expand the feedstock of zinc industry, increase efficiency of steel making and
reduce negative impact on environment.
The paper contains chemical and mineralogical analysis of steel dust sample from
PAO Severstal and study results on hydrometallurgical extraction of zinc from dust
using salt solution. It has been established that ammonium chloride leaching of zinc
Ferrosilicon productiion and submerged arc furnace (1)Nasser Harby
Ferroalloys, by definition, are alloys of two or more metals, of which one is Iron. The U.S. Bureau of Mines defines ferroalloy as an alloy of iron with at least one other element except for carbon.
The main indicator of the quality of a ferroalloy is its chemical composition and, above all, the content of the leading element. It is important to have Consistency in alloying element amounts in ferroalloys from heat to heat, allowing the manufacture of standard products
The smelting of ferroalloys is commonly performed in electric arc furnaces.
Although ferromanganese can be produced in a blast furnace in a manner similar to iron, the reduction of chromium and silicon from their oxides requires higher Process temperatures and lower oxygen potentials than can be achieved in a blast furnace
Raw materials are perhaps the most important factor for obtaining good furnace operation the first step towards improvements is to reduce the variations
The aim of this course is to present the basic principles for the production of ferrosilicon alloys processes, and a simple preview for submerged arc furnaces.
It is attended for Engineers working in this field, and students or metallurgists maybe find answers for their questions, because at the end of this course you will figure out that you have a preview for this manufacture and the main problems and solutions for the ferrosilicon production process. And having an overview for submerged arc furnaces design and operations.
.
IJERA (International journal of Engineering Research and Applications) is International online, ... peer reviewed journal. For more detail or submit your article, please visit www.ijera.com
ANALYTICAL TOOL FOR ANALYSING SLAGGING CHARACTERISTIC OF HIGH ASH COALS IN UT...IAEME Publication
In today’s competitive market, the performance of electric utility industry is a
serious concern to the nation. Majority of power plants are Coal-Fired Power plants
in India. Due to the wide variation in the quality of coal being fired, it affects the
performance of the power plant like furnace wall slagging, convective pass slagging
(both Low and High Temperature), soot blower effectiveness, erosion and
grindability. At this juncture, a reliable prediction is needed to assess the slagging
problem which in turn affects the performance parameters of power plant like heat
transfer rate, exit gas temperature, surface corrosion and frequency of soot blowing.
Though conventional indices and ash fusion temperature measurement techniques
do not aid in predicting slagging condition with field performance hence, it is reported
to be highly subjective in nature and poor accuracy.
In this work an alternative approach is made based on shrinkage measurement up
to 1400 °C of coal ash prepared at 800 °C. Sensitive shrinkage measurements indicate
temperatures of rapid change which correspond to the formation of liquid phases.
A preliminary evaluation of shrinkage data for coal ash collected at different
power stations firing wide variety of coal indicates that, the shrinkage profiles of the
ashes are differing widely and rate of shrinkage measurement can provide an
alternative approach to characterize/assess the slagging potential. Shrinkage
measurement of coal ash has been carried out for the coal ashes collected at different
power stations using different quality of coal
Welding Studies on WB36 for Feed Water Pipingijceronline
To increase efficiency, reduce emissions, cost and to reduce weight of boiler per MW, the power manufacturing sectors are going towards the once through technology (super critical boiler) instead of sub- critical. Once through supercritical (OTSC) technology has become a focal point for effective utilization of coal-based thermal power generation sector in India. Another main advantage of moving towards OTSC technology is reducing the weight of the boiler per MW, which can be done by going for material capable of handling higher pressure and temperature than the conventional material. So, in order to keep pace with these technologies, research on newer materials for every boilers line, which can operate at both higher pressure and temperature, has been initiated. So, in this article, we have taken one such feed water system and headers, where WB 36 steel (15 MiCuMoNiNb5) can be used instead conventional standard carbon steel like A106 grade B or C, which are usually used. For super critical, ultra super critical power plants this conventional materials like A106 grade B or C, leads to very thick piping system. V&M has developed WB 36 steel (15 MiCuMoNiNb5) for high pressure piping of boiler feed water system. This heat-resistant, copperalloyed ferritic steel 15MiCuMoNiNb5 has been widely used in European nuclear and conventional power plants for decades for feed water system. This widespread application is due to the toughness and strength, caused by the precipitation of copper, that are exhibited even at elevated temperatures which other fine-grained structural steels have at room temperature. The aim of this project “Welding Studies on WB36 Steel for Feed Water Piping” was taken to understand the metallurgy and the behavior of the new materials under different manufacturing operations.
Madkour 1986-journal of-chemical_technology_and_biotechnologyAl Baha University
Thermodynamic Studies on Sulphate Roasting for Zinc Electrowinning from Carbonate Ore
The bulk of the work consists of a theoretical study of the possibility of submitting Umm-Gheig carbonate ore to sulphate roasting. The use of the admixture with pyrites is to enable a carbonate ore to be treated in a similar way to a sulphide ore, and by doing so, to produce a roasted product capable of being treated by orthodox zinc electrowinning methods using sulphate solutions. Thermodynamic studies have been made to find the optimum conditions for sulphate roasting, in either normal air or enriched 36% oxygen air. The results obtained from the experimental work at different roasting temperatures in a tube furnace indicated that a maximum dissolu- tion of 91.2% Zn with a 17.9% Fe could be obtained at a roasting temperature of 650°C for 4 h, followed by leaching in 4% H2S04 (by vol.) at 60°C. The results of the electron microscopic investigation confirmed by metal value data given in the ASTM cards coincide well with results given by chemical analysis
Simulation of non metallic inclusions formation during liquid steel reoxidizingAlexander Alexeenko
Processes of inclusions formation during steel reoxidizing were investigated by computer simulation and SEM analysis of oxide inclusions in steel samples. The thermodynamic-based model of interaction between oxide inclusions and liquid metal in the line of equilibrium state and program for computation of inclusions transformation are developed. For Al- and Si-killed steels trajectories of change of inclusions chemical composition from initial FexO phase formed during reoxidation to final inclusions oxide phases were computed. Those finals phases are: heterogeneous inclusions (grains of hard spinals solution |MnO.Al2O3,FeO.Al2O3| + interlayers from phase based on MnO–SiO2–Al2O3 system, and Al2O3 cover) in LCAK-steel with Si content 0.01 wt. pct; hard inclusions based on Al2O3–MnO–SiO2 system in LCAK-steel with Si content 0.2 wt. pct, manganese silicates in medium carbon Si-killed steel. Computer simulation of inclusion transformation in LCAK-steel showed that Si significantly increases a time of transformation from initial liquid phase FexO to hard phases. It explains the well-known fact that LCAK-steels with Si > 0.1 wt. pct has better castability than low silicon ones.
Effect of Sintering Temperature on Mechanical Properties of Aluminum Compositesijtsrd
Using Al, Al2O3 and SiC, different types of composites have been prepared in this experiment. Green compacts of Al composites were made at a compressing load of 1 ton and 2 ton respectively. These compacts were sintered at two different sintering temperatures of 400 °C and 450 °C in an oxygen free environment using muffle furnace for one hour followed by annealing process which took 12 hours. Sintered compacts were then sintered to micro structural examination and mechanical properties evaluation. Higher hardness has been attained for the composites containing 2.5 SiC. Attempts have been made to describe the influence of sintering temperature on the microstructure and properties of Al Al2O3 SiC composites. Samples are prepared of 100 Al, 97.5 Al 2.5 Al2O3, 92.5 Al 7.5 Al2O3, 95 Al 2.5 Al2O3 – 2.5 SiC, 92.5 Al 5 Al2O3 – 2.5 SiC, 95 Al – 5 Al2O3. The main objective of this experiment is to determine the factors that can increase hardness of Al composites. Mohd Quasim Khan ""Effect of Sintering Temperature on Mechanical Properties of Aluminum Composites"" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-3 | Issue-4 , June 2019, URL: https://www.ijtsrd.com/papers/ijtsrd25073.pdf
Paper URL: https://www.ijtsrd.com/engineering/mechanical-engineering/25073/effect-of-sintering-temperature-on-mechanical-properties-of-aluminum-composites/mohd-quasim-khan
Kinetics of formation of fe2 b layers on aisi s1 steeluaeh
Boriding is our favourite method to harden steels. That is also why we have developed a special boriding treatment that works even better than regular boriding, called BoroCoat®.
Boriding is a thermochemical heat treatment that diffuses boron into the surface of a workpiece. The boride layer that is formed on top is extremely wear resistant and protects the workpiece from chemical attacks as well as abrasive wear and cold welding.
Boron can be applied as a powder, as a paste and as granules, making possible the treatment of almost any type of workpiece, no matter their design. Boriding is extremely effective when it comes to corrosion resistance and can be applied to workpieces in mechanical engineering, for valves and for power tools.
It is known that one of the major negative impacts of the corrosion of steel
structures is the reduction in geometry. The calculations of the load-bearing capacity
of the steel elements depend on the geometric characteristics. The theory confirms that
if the geometric characteristics decrease, the load-bearing capacity of the steel
elements will also decrease. We conducted an experiment using the S355JR
construction steel to determine how the geometry changes. We used electro-chemical
accelerated corrosion on which our steel test samples were subjected. We interrupted
the electrochemical corrosion process at some point in order to make the necessary
measurements regarding the change in geometric characteristics of the test samples.
Once we received the experimental data, we processed them using the stochastic
method. We also performed theoretical calculations using classical theory and
determined the theoretical load-ability (force, bending moment) of our test samples.
We have come to the conclusion that the change in geometric characteristics is nonlinear
and results in a slight decrease in the corrosion of the steel elements, but
significantly reduces the theoretical ultimate load-capacity due to corrosion and the
corresponding decrease in geometric characteristics
IJERA (International journal of Engineering Research and Applications) is International online, ... peer reviewed journal. For more detail or submit your article, please visit www.ijera.com
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Feasibility Study of Synthesis of Nanostructured Aluminum Nitride Through Sol...IJERA Editor
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc
Welding Studies on WB36 for Feed Water Pipingijceronline
To increase efficiency, reduce emissions, cost and to reduce weight of boiler per MW, the power manufacturing sectors are going towards the once through technology (super critical boiler) instead of sub- critical. Once through supercritical (OTSC) technology has become a focal point for effective utilization of coal-based thermal power generation sector in India. Another main advantage of moving towards OTSC technology is reducing the weight of the boiler per MW, which can be done by going for material capable of handling higher pressure and temperature than the conventional material. So, in order to keep pace with these technologies, research on newer materials for every boilers line, which can operate at both higher pressure and temperature, has been initiated. So, in this article, we have taken one such feed water system and headers, where WB 36 steel (15 MiCuMoNiNb5) can be used instead conventional standard carbon steel like A106 grade B or C, which are usually used. For super critical, ultra super critical power plants this conventional materials like A106 grade B or C, leads to very thick piping system. V&M has developed WB 36 steel (15 MiCuMoNiNb5) for high pressure piping of boiler feed water system. This heat-resistant, copperalloyed ferritic steel 15MiCuMoNiNb5 has been widely used in European nuclear and conventional power plants for decades for feed water system. This widespread application is due to the toughness and strength, caused by the precipitation of copper, that are exhibited even at elevated temperatures which other fine-grained structural steels have at room temperature. The aim of this project “Welding Studies on WB36 Steel for Feed Water Piping” was taken to understand the metallurgy and the behavior of the new materials under different manufacturing operations.
Madkour 1986-journal of-chemical_technology_and_biotechnologyAl Baha University
Thermodynamic Studies on Sulphate Roasting for Zinc Electrowinning from Carbonate Ore
The bulk of the work consists of a theoretical study of the possibility of submitting Umm-Gheig carbonate ore to sulphate roasting. The use of the admixture with pyrites is to enable a carbonate ore to be treated in a similar way to a sulphide ore, and by doing so, to produce a roasted product capable of being treated by orthodox zinc electrowinning methods using sulphate solutions. Thermodynamic studies have been made to find the optimum conditions for sulphate roasting, in either normal air or enriched 36% oxygen air. The results obtained from the experimental work at different roasting temperatures in a tube furnace indicated that a maximum dissolu- tion of 91.2% Zn with a 17.9% Fe could be obtained at a roasting temperature of 650°C for 4 h, followed by leaching in 4% H2S04 (by vol.) at 60°C. The results of the electron microscopic investigation confirmed by metal value data given in the ASTM cards coincide well with results given by chemical analysis
Simulation of non metallic inclusions formation during liquid steel reoxidizingAlexander Alexeenko
Processes of inclusions formation during steel reoxidizing were investigated by computer simulation and SEM analysis of oxide inclusions in steel samples. The thermodynamic-based model of interaction between oxide inclusions and liquid metal in the line of equilibrium state and program for computation of inclusions transformation are developed. For Al- and Si-killed steels trajectories of change of inclusions chemical composition from initial FexO phase formed during reoxidation to final inclusions oxide phases were computed. Those finals phases are: heterogeneous inclusions (grains of hard spinals solution |MnO.Al2O3,FeO.Al2O3| + interlayers from phase based on MnO–SiO2–Al2O3 system, and Al2O3 cover) in LCAK-steel with Si content 0.01 wt. pct; hard inclusions based on Al2O3–MnO–SiO2 system in LCAK-steel with Si content 0.2 wt. pct, manganese silicates in medium carbon Si-killed steel. Computer simulation of inclusion transformation in LCAK-steel showed that Si significantly increases a time of transformation from initial liquid phase FexO to hard phases. It explains the well-known fact that LCAK-steels with Si > 0.1 wt. pct has better castability than low silicon ones.
Effect of Sintering Temperature on Mechanical Properties of Aluminum Compositesijtsrd
Using Al, Al2O3 and SiC, different types of composites have been prepared in this experiment. Green compacts of Al composites were made at a compressing load of 1 ton and 2 ton respectively. These compacts were sintered at two different sintering temperatures of 400 °C and 450 °C in an oxygen free environment using muffle furnace for one hour followed by annealing process which took 12 hours. Sintered compacts were then sintered to micro structural examination and mechanical properties evaluation. Higher hardness has been attained for the composites containing 2.5 SiC. Attempts have been made to describe the influence of sintering temperature on the microstructure and properties of Al Al2O3 SiC composites. Samples are prepared of 100 Al, 97.5 Al 2.5 Al2O3, 92.5 Al 7.5 Al2O3, 95 Al 2.5 Al2O3 – 2.5 SiC, 92.5 Al 5 Al2O3 – 2.5 SiC, 95 Al – 5 Al2O3. The main objective of this experiment is to determine the factors that can increase hardness of Al composites. Mohd Quasim Khan ""Effect of Sintering Temperature on Mechanical Properties of Aluminum Composites"" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-3 | Issue-4 , June 2019, URL: https://www.ijtsrd.com/papers/ijtsrd25073.pdf
Paper URL: https://www.ijtsrd.com/engineering/mechanical-engineering/25073/effect-of-sintering-temperature-on-mechanical-properties-of-aluminum-composites/mohd-quasim-khan
Kinetics of formation of fe2 b layers on aisi s1 steeluaeh
Boriding is our favourite method to harden steels. That is also why we have developed a special boriding treatment that works even better than regular boriding, called BoroCoat®.
Boriding is a thermochemical heat treatment that diffuses boron into the surface of a workpiece. The boride layer that is formed on top is extremely wear resistant and protects the workpiece from chemical attacks as well as abrasive wear and cold welding.
Boron can be applied as a powder, as a paste and as granules, making possible the treatment of almost any type of workpiece, no matter their design. Boriding is extremely effective when it comes to corrosion resistance and can be applied to workpieces in mechanical engineering, for valves and for power tools.
It is known that one of the major negative impacts of the corrosion of steel
structures is the reduction in geometry. The calculations of the load-bearing capacity
of the steel elements depend on the geometric characteristics. The theory confirms that
if the geometric characteristics decrease, the load-bearing capacity of the steel
elements will also decrease. We conducted an experiment using the S355JR
construction steel to determine how the geometry changes. We used electro-chemical
accelerated corrosion on which our steel test samples were subjected. We interrupted
the electrochemical corrosion process at some point in order to make the necessary
measurements regarding the change in geometric characteristics of the test samples.
Once we received the experimental data, we processed them using the stochastic
method. We also performed theoretical calculations using classical theory and
determined the theoretical load-ability (force, bending moment) of our test samples.
We have come to the conclusion that the change in geometric characteristics is nonlinear
and results in a slight decrease in the corrosion of the steel elements, but
significantly reduces the theoretical ultimate load-capacity due to corrosion and the
corresponding decrease in geometric characteristics
IJERA (International journal of Engineering Research and Applications) is International online, ... peer reviewed journal. For more detail or submit your article, please visit www.ijera.com
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Feasibility Study of Synthesis of Nanostructured Aluminum Nitride Through Sol...IJERA Editor
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc
Study the effect of Mn2+ ions on the ac electrical properties of some iron do...IJRES Journal
Oxide glasses doped with transition metal ions are of high interest because of their variant applications in both science and technology fields. However, the normal melt quench method have used to prepared some iron doped phosphate glasses according the following molecular formula: (65-x) mol% P2O5 - 20 mol% Na2O - 15 mol% Fe2O3 - x mol% MnO, Where x= 0, 5,10, 20, 25. The room temperature Mössbauer Effect ME Spectra used to characterized the glassy state homogeneity of these glasses. ME spectra show, for all glasses, no magnetic field participate which mean good glassy state formation. The ac electrical transport properties were also measured, as function of temperature up to 500k. It was found that the ac conductivity increased with the gradual increase of Mn2+ cations, while the electrical activation energy decreased.
Inhibition Effect of Hydantoin Compounds on the Corrosion of Iron in Nitric a...Al Baha University
The inhibition of corrosion of iron in 2M nitric acid and 2M sulfuric acid solutions by substituted phenylhydantoin, thiohydantoin, and dithiohydantoin compounds was measured using thermometric, weight loss, and polarization methods. The three methods gave consistent results. The polarization curves indicated that the hydantoin compounds act as mixed-type inhibitors. The adsorption of the inhibitors were found to obey the Temkin adsorption isotherm. The higher inhibition ef®ciency of the additives in nitric with respect to sulfuric acid solution may be attributed to the reduced formation of soluble quaternary nitrogen salts in nitric acid medium, favouring adsorption of the parent additive on the metal surface. The obtained results indicate that the corrosion rate of iron in both acids increases with increasing temperature, both in absence and presence of the tested inhibitors. Kinetic-thermodynamic model functions and Temkin isotherm data are compared and discussed. The synergistic effect of halide anions on the inhibition ef®ciency of the hydantoin compounds was also investigated.
IrO2 as an anodic electrocatalyst for the oxygen evolution reaction (OER) in solid polymer electrolyte (SPE)
electrolysers was synthesised by adapting the Adams fusion method. Optimisation of the IrO2 electrocatalyst was achieved
by varying the synthesis duration (0.5 – 4 hours) and temperature (250 - 500°C). The physical properties of the
electrocatalysts were characterised by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and
x-ray diffraction (XRD). Electrochemical characterisation of the electrocatalysts toward the OER was evaluated by
chronoamperometry (CA). CA analysis revealed the best electrocatalytic activity towards the OER for IrO2 synthesised
for 2 hours at 350oC which displayed a better electrocatalytic activity than the commercial IrO2 electrocatalyst used in this
study. XRD and TEM analyses revealed an increase in crystallinity and average particle size with increasing synthesis
duration and temperature which accounted for the decreasing electrocatalytic activity. At 250°C the formation of an active
IrO2 electrocatalyst was not favoured.
The Expander Gas and Ammonia Ratio Influence on the Calcium Cyanamide YieldYogeshIJTSRD
For the first time, thermodynamic calculations based on relatively new physicochemical constants clarified the onset temperature of thermal ammonia decomposition, as well as the side chemical reactions probability between ammonia and carbon dioxide. The influence of the main technological parameters on the calcium cyanamide synthesis is investigated. The exhaust gases composition from the reactor for the calcium cyanamide synthesis was studied depending on the temperature. Kinetic studies of the calcium cyanamide synthesis determined the chemical reaction orders with respect to ammonia and carbon dioxide, and it was proved that the limiting stage of calcium cyanamide synthesis is the initial gas components diffusion through the product layer. O. Kh. Panzhiev | A. Kh. Panzhiev | N. Umarov | O. Azimov "The Expander Gas and Ammonia Ratio Influence on the Calcium Cyanamide Yield" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Special Issue | International Research Development and Scientific Excellence in Academic Life , March 2021, URL: https://www.ijtsrd.com/papers/ijtsrd38440.pdf Paper Url: https://www.ijtsrd.com/engineering/other/38440/the-expander-gas-and-ammonia-ratio-influence-on-the-calcium-cyanamide-yield/o-kh-panzhiev
Simple and Effective Method of the Synthesis of Nanosized Fe2O 3particlesIOSR Journals
Abstract: Nanosized Iron oxide is prepared by using precipitation method from iron nitrate and liquid ammonia. Thermal analysis shows that synthesized iron oxide shows some weight loss and oxide undergoing decomposition, dehydration or any physical change from TGA curve we observe that Iron oxide shows stable weight loss above 4000C. In DTA curve also, there is exothermic and endothermic peak. Which shows phase transition, solid state reaction or any chemical reaction occurred during heating treatment. Morphology is observed by scanning electron microscopy (SEM) shows particles are nanosized. Further morphology observation by Transmission Electron Microscopy (TEM) revels that Iron Oxide has the corundum (Al2O3) structure. Magnetic measurements shows that iron oxide has five unpaired electron and strongly paramagnetic character.
Studies on Corrosion Characteristics of Carbon Steel Exposed to Na2CO3, Na2SO...theijes
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
The papers for publication in The International Journal of Engineering& Science are selected through rigorous peer reviews to ensure originality, timeliness, relevance, and readability.
Efforts made in many countries to stop the COVID-19 pandemic include vaccinations. However,
public skepticism about vaccines is a pressing issue for health authorities. With the COVID-19 vaccine
available,
SARS-CoV-2, as the causative agent of COVID-19, has spread throughout the world after becoming
a pandemic in March 2020. In the midst of the ongoing COVID-19 pandemic, we are also faced with another
serious health problem
This paper discusses the construction and implementation of a system for the measurement of
electrical power parameters; amperage and voltage of the hybrid system photovoltaic solar-wind, to evaluate
the system parameters and performance. The basis of the development of the measuring apparatus is the use of
an Arduino Mega 2560 to provide the interface between the electrical circuits of the sensors and the dynamics
of the voltage-amperage as well as collect data in an analog format as well as development of functional
dependence relationships. The collected data is converted into digital format and stored it in an Excel format
through the "PLX-DAQ Spreadsheet" that connects the Arduino and the PC for display and analysis of the
system parameters. The proposed technique for power measurements of AC and DC proved to be reliable and
can predict the power amperage and voltage within relative error of 1.63 % for AC and 4.16% for DC,
respectively.
The optimum speed required for mass-size reduction of shells to produce most sizes that are small
comparable with kernel sizes; coupled with retention of kernel wholeness in cracked palm nut mixture under
repeated impact was investigated. This is to enhance whole kernel separation by dry method, reduce maintenance
and production cost of palm kernel oil (PK0); and lower the risk of oil rancidity associated with split kernel
production and wet method of separation. A static nut cracker and centrifugal nut cracker were used in this study as
Test Rigs while sieves were used to grade cracked shells and whole kernels. The data generated were evaluated. A
model was developed for energy via speed required to retain kernels wholeness following repeated impact in the
crackers. Technical analysis revealed that the maximum allowable speed to retain kernel wholeness is 27.93 m/s;
the minimum allowable average speed to fragment cracked shells is 24.95 m/s. Further analysis showed that the
optimum speed and energy required for cracked nut mixture under repeated impact to have kernel wholeness
retention and production of small sizes of cracked shells relative to kernel sizes are 25.71 m/s and 0.4 J,
respectively.
This review was written to provide a comprehensive summary of the suggested etiologies of Chronic Kidney
Disease of Unknown Etiology (CKDu) in Sri Lanka. In this review, Chronic Kidney Disease (CKD) is explained
in detail and its known etiologies are discussed. CKDu is defined and its epidemiology is discussed, with the
compilation of statistic from over 15 research papers through the years 2000 to present.
This work contributes to the monitoring of water pollution of some selected Dams in Katsina
State, North western Nigeria by assessing the degree of heavy metal pollution in the Dams sediment samples.
The study was conducted in the year 2017 within some selected Dams in the State (Ajiwa, Zobe,
Sabke/Dannakola) that are beehives of fishing and Agricultural activities in Katsina State. Analysis for the
concentration of these heavy metals; Cr, Cd, Fe, Ni, Mn, Pb and Zn was conducted by the use of AAS (by
Atomic Absorption Spectrophotometry) method. Several indices were used to assess the metal contamination
levels in the sediment samples, namely; Geo-accumulation Index (Igeo), Enrichment Factor (EF),
Contamination Factor (CF), Degree of Contamination (Cd), Pollution Load Index (PLI) and Potential
Ecological Risk Index (PERI). The result of this study has shown that generally among the heavy metals
evaluated, the highest concentration was observed for Fe (range: 2.6718-4.2830 ppm), followed by Zn (range:
0.4265-0.7376 ppm), Cr (range: 0.1106-0.1836 ppm), Cd (range: 0.1333-0.1273 ppm) and Mn (range: 0.1136-
0.1271 ppm). While Pb has the lowest concentration (range: 0.0472-0.0598 ppm). For all the site sampled the
heavy metal Ni was below detection level (BDL). From the results of heavy metals I-geo values, according to
Muller’s classification, all the sediment samples from the selected dams were unpolluted (class 0). The result for
the enrichment factor has shown that for all the selected dam sediment samples the heavy metals show
deficiency to minimal enrichment. Also based on the contamination factors for all sediment samples the heavy
metal Cd has a CF values range of 0.5430-0.6665 (~1), indicating that the sediment samples are moderately
contaminated with Cd. In contrast, the rest of the heavy metals exhibit low contamination in general. The value
of PLI ranges from 0.2408 to 0.4935, indicating unpolluted to moderate pollution. The Eri values for all
samples are all < 40, presenting low ecological risk. The results suggest that the sediment samples from the
selected dams in Katsina state has low contamination by the heavy metals evaluated.
Using QR Decomposition to calculate the sum of squares of a model has a limitation that the number of rows,
which is also the number of observations or responses, has to be greater than the total number of parameters used in the
model. The main goal in the experimental design model, as a part of the Linear Model, is to analyze the estimable function
of the parameters used in the model. In order not to deal with generalized invers, partitioned design matrix may be used
instead. This partitioned design matrix method may be used to calculate the sum of squares of the models whenever the total
number of parameters is greater than the number of observations. It can also be used to find the degrees of freedom of each
source of variation components. This method is discussed in a Balanced Nested-Factorial Experimental Design.
Introduction:It has been proven twice that the Hambantota District has the highest life expectancy in male
population. This study focused to find and identify reasons for Hambantota District people to have high life
expectancy at birth.
Methodology: Research was carried out in both qualitative and quantitative phases in five MOH (Medical
Health Officer) divisions in HambantotaDistrict. Study focused on 3 age categories, 55-65 Years, 66-75 Years,
and above 76 Years. Main objectives and key information areas are Life Style and Social Behaviors, Food
Consumption and Diet, Familial Trait and Physical and Mental Health.
Findings: Majority of the male population have educated up to grade 5and most are engaged in the agriculture
while others engaged in fishery and self-employment etc. Almost everyone reachestheir workplaces by foot or by
bicycle. Many of them work less than six hours. They spend their free time with their family members and watch
TV. Most of them do not consume alcohol and smoke. Almost everyone take part in social activities. Majority eat
red rice for all three meals. Almost everyone eats fish every day. They have a high salt intake. Their parents and
ancestors have also have had a high life expectancy. Only a minority suffer from chronic illnesses. They all have
a good physical and mental health condition. They spend happy and relaxed lifestyle.
Conclusion: Healthy diet, low alcohols consumption and smoking, high iodine intake, physical activeness and
their social wellbeing effect for high life expectancy within the male population of selected five MOH divisions
in Hambantota District. They have a free and happy life. Genetics of these people also may contribute for high
life expectancy. Abundance of neem trees in this area also may effect on their high life expectancy.
A clay deposit in Chavakali of western Kenya was evaluated for its potential as refractory raw
material. The collected clay sample was crushed, sieved and the chemical composition determined in
percentage weight (wt %) of (SiO2, Al2O3, Fe2O3, etc) using Atomic Absorption Spectrophotometer (AAS). The
samples were moulded into rectangular shaped bricks of 40mm height, 40mm width and 80mm length, allowed
to dry and later fired up to a temperature of 10000C. Refractory properties like Compressive strength,
Hardness, Linear shrinkage on firing, Apparent porosity and Density were determined using standard
techniques. The result of chemical analysis indicated that the clay was composed of Silica (SiO2), 67.3%;
Alumina (Al2O3), 16.67%; Iron Oxide (Fe2O3), 3.87%; Calcium Oxide (CaO), 0.37%; Potassium Oxide (K2O),
2.30%; Sodium Oxide (Na2O), 1.39%; and other traces. The physical and mechanical tests show that the clay
has Cold Crushing Strength of 10.36MPa, Hardness of 40.080 GPa, Linear shrinkage of 6.17%, Apparent
Porosity of 32.71% and Bulk Density of 2.77g/cm3
. Chavakali clay can make better local refractory
Nihon University challenged world record of the human-powered aircraft flight based on the
regulation of Fédération Aérionautique Internationale in Kasumigaura Lake, Japan, 2014. The wing fell off in
midair immediately after take-off, the pilot landed to the lake for safety. So, the challenge failed. It guessed the
operational errors were correlated with the wing falling in midair, which had not happened in our experience.
The flight recording camera and the salvaged airplane were investigated. The fault tree analysis was conducted
for cause investigation. The wing falling was the result as the chain destruction starting from the coupling parts
being damaged in take-off. The defective take-off was caused by composite factors on only operational errors.
The risk that the ultralight airplane might disintegrate in midair by only operational error became apparent.
Due to the large-scale exploitation of mineral resources and the unreasonable human activities, the
geological disasters in Jiaozuo City have become increasingly prominent and the degree of harm increased. This
leds to a tremendous threat to human life and property safety. Jiaozuo City, the main types of geological
disasters, landslides, ground subsidence, debris flow and ground fissures. It has great significance to the
development of the city and the protection of people's life and property to explore the hidden dangers of
geological disasters and actively take preventive and control measures. The establishment of geological
hazard group measurement system of prevention and control to achieve the timely detection of geological
disasters, rapid early warning and effective avoidance.
Dangerous gas explosion accidents result in considerable amount of casualties and property damage.
Hence, an investigation on the generation of poisonous gases in gas explosions exerts important implications
for accident prevention and control and in the decision-making processes of fire rescue. Therefore, a gas
explosion piping test system is established in this paper. Experimental research on gas explosion is conducted by
selecting methane/air premixed gases with concentrations of 7%, 9%, 11%, 13%, and 15% in the gas explosive
range. This research aims to reveal the regularity of CO generation after gas explosion in pipelines.
Experimental results showed that when the gas concentration is small (< 9%), 1500–3000 ppm CO will be
produced. When the gas concentration is large (> 9%), the CO amount will reach 3000–40000 ppm. The
variation trend in CO concentration and the quantity of explosive gas are also obtained.
To evaluate the influence of the entry speed to flow field above the water surface on an object
high-speed entering into water, the flow field was measured experimentally by using an optical visualization
method. The entry speed was ranging from 0.2 to 1.5 km/s. In case that the entry speed was higher than the
sound speed of gas above the water surface, the vertical velocity of the tip of a water splash was linear to the
vertical location of the tip. The ratio between the initial vertical velocity of a water splash and the entry speed
was independent from the entry speed and was constant.A shock wave was driven above the water surface by the
entry even thoughthe entry speed was lower than the sound speed of gas above the water surface.A scaling law
for the propagation of a shock wave driven by explosion of an explosive was applicable to the propagation of
the shock wave driven by the water entry by using the kinetic energy of the entry object instead of the explosive
energy.
Pingdingshan Coal Mine district is one of the six mining areas of Henan Province, which is a
large coal base in China. After 60 years of exploitation, it has brought great benefits, at the same time,
serious geological disasters have been occurred. It has seriously damaged the normal production of the
masses, life, restricting the development of Pingdingshan coal mine economy. In this paper, the
geological disasters such as ground collapse, ground fissures and ground subsidence in Pingdingshan coal
mine are analyzed, and the degree of geological disasters in the mining area is analyzed in combination
with the severely affected mining area. Finally, reasonable and feasible countermeasures have been put
forward.
Kelud volcano is located in East Java Province, Indonesia. According to Geochemical study of
Kelud Volcano, it could be divided into 3 periods which are Kelud I (older than 100 ky BP), Kelud II (40 – 100
ky BP), and Kelud III (younger than 40 ky BP). A specific petrogenesis of Kelud are dominatad by magma
mixing and fractional crystalization. New petrological data from Kelud volcano was taken through products of
the eruption in 1990 (Vulkanian type), 2007 (Lava plug forming) and 2014 (Plinian type). Petrographic study
on these rocks showed that reverse and oscilatory zoning on plagioclases, Shieve-like and corroded textures on
plagioclases and pyroxenes are common. However, normal zoning textures were also found on plagioclases and
pyroxenes. Whole rock study on these rocks showed all rocks were classified into Basalt to Andesite in
composition with calc-alkaline group. The study indicated that their magma origin derrived from slab with
fractional crystallization during in the magma reservoir, and magma mixing processes are dominant expecially
in magma pockets. Concequently, the magma origin and petrogenesis of Kelud magma after the 1966 eruption
are still the same as those of old magma of Kelud.
Black cotton soils are among a group of soils termed as problematic soils. These soils have
undesirable characteristics in relation to construction works and therefore need some form of improvement
when encountered in construction projects. Techniques for improvement of black cotton soils include
replacement, moisture control or adding a stabilizer. Cement and/or lime has been commonly used in soil
stabilization for ages. However, due to the associated cost, required quality control and the need to utilize waste
materials in construction, new stabilizing materials are emerging. This paper presents a study on application of
quarry dust for improving properties of black cotton soil in Mbeya region, Tanzania. The targeted improvement
was to achieve minimum acceptable characteristics for road subgrade as per Tanzania standards. It was
determined that 40% by weight of quarry dust added to the black cotton soil was able to improve the
characteristics by increasing CBR value from 3.8 to 15.7 and reducing PI from 32% to 15%. It will be worthy
studying the cost implication of the suggested improvement in relation to other techniques before application of
the study findings.
High intensity rain and morphometri in Padang city cause at Arau. Morphometri
geomorphologi that is related to wide of, river network, stream pattern and gradien of river. The form wide
of DAS will be by stream pattern and level.This will influence to the number of rain. Make an index to
closeness of stream depict closeness of river stream at one particular DAS. Speed of river stream influenced
by storey, level steepness of river. Steepness storey, level is comparison of difference height of river
downstream and upstream. Ever greater of steepness of river stream, excelsior speed of river stream that
way on the contrary. High to lower speed of river stream influence occurence of floods, more than anything
else if when influenced by debit big. By using rainfall from year 2005 to year 2015, and use Thiessen method
got a rainfall. Use the DEM IFSAR, analysed sofware ARGIS, and with from earth map, the result got DAS
in at condition of floods gristle and sedimentation. There are band evakuasi for resident which data in
floods area.
The chemical (extractives and lignin) content and histological property (microscopic structure)
of tissues of Ricinodendron heudelotii (Baill, Pierre ex Pax), an angiosperm, were investigated for its potential
as a fibrous raw material for pulp and paper production. Bolts of about 70 cm were cut from the felled trees at
three different merchantable height levels of 10%, 50%, and 90% to obtain: corewood, middlewood and
outerwood samples. The fiber characteristics of the selected trees viz: the fiber length, fibre diameter and lumen
diameter were measured while the cell wall thickness was derived from the measured fibre dimensions. The
average fiber length, cell wall thickness, and lumen width, were 1.40 mm, 4.6 µm, and 32.3 µm, respectively.
The extractive and lignin contents were determined. Klason lignin content was about 30%. Extractive content of
R. heudelotii ranged from 0.41 to 0.5%. Based on these findings R. heudelotii is suitable for pulp and paper
production.
The prolific Niger Delta Basin is a mature petroleum province. Therefore, further prospectivity in
the basin lies within deeper plays which are high pressure and high temperature (HPHT) targets. One of the
main characteristics of the Niger Delta is its unique diachronous tripartite stratigraphy. Its gross onshore and
shallow offshore lithostratigraphy consists of the deep-seated Akata Formation and is virtually exclusively
shale, the petroliferous paralic Agbada Formation in which sand/shale proportion systematically increases
upward, and at the top the Benin Formation composed almost exclusively of sand. This stratigraphic pattern is
not exactly replicated in the deep offshore part of the delta.
A low-carbon steel wire of AISI 1022 is used to easily fabricate into self-drilling tapping screws,
which are widely used for construction works. The majority of carbonitriding activity is performed to improve
the wear resistance without affecting the soft, tough interior of the screws in self-drilling operation. In this
study, Taguchi technique is used to obtain optimum carbonitriding conditions to improve the mechanical
properties of AISI 1022 self-drilling tapping screws. The carbonitriding qualities of self-drilling tapping screws
are affected by various factors, such as quenching temperature, carbonitriding time, atmosphere composition
(carbon potential and ammonia level), tempering temperature and tempering time. The quality characteristics of
carbonitrided tapping screws, such as case hardness and core hardness, are investigated, and so are their
process capabilities. It is experimentally revealed that the factors of carbonitriding time and tempering
temperature are significant for case hardness. The optimum mean case hardness is 649.2HV. For the case
hardness, the optimum process-capability ratio increases by about 200% compared to the original result. The
new carbonitriding parameter settings evidently improve the performance measures over their values at the
original settings. The strength of the carbonitrided AISI 1022 self-drilling tapping screws is effectively improved.
More from International journal of scientific and technical research in engineering (IJSTRE) (20)
Explore the innovative world of trenchless pipe repair with our comprehensive guide, "The Benefits and Techniques of Trenchless Pipe Repair." This document delves into the modern methods of repairing underground pipes without the need for extensive excavation, highlighting the numerous advantages and the latest techniques used in the industry.
Learn about the cost savings, reduced environmental impact, and minimal disruption associated with trenchless technology. Discover detailed explanations of popular techniques such as pipe bursting, cured-in-place pipe (CIPP) lining, and directional drilling. Understand how these methods can be applied to various types of infrastructure, from residential plumbing to large-scale municipal systems.
Ideal for homeowners, contractors, engineers, and anyone interested in modern plumbing solutions, this guide provides valuable insights into why trenchless pipe repair is becoming the preferred choice for pipe rehabilitation. Stay informed about the latest advancements and best practices in the field.
Automobile Management System Project Report.pdfKamal Acharya
The proposed project is developed to manage the automobile in the automobile dealer company. The main module in this project is login, automobile management, customer management, sales, complaints and reports. The first module is the login. The automobile showroom owner should login to the project for usage. The username and password are verified and if it is correct, next form opens. If the username and password are not correct, it shows the error message.
When a customer search for a automobile, if the automobile is available, they will be taken to a page that shows the details of the automobile including automobile name, automobile ID, quantity, price etc. “Automobile Management System” is useful for maintaining automobiles, customers effectively and hence helps for establishing good relation between customer and automobile organization. It contains various customized modules for effectively maintaining automobiles and stock information accurately and safely.
When the automobile is sold to the customer, stock will be reduced automatically. When a new purchase is made, stock will be increased automatically. While selecting automobiles for sale, the proposed software will automatically check for total number of available stock of that particular item, if the total stock of that particular item is less than 5, software will notify the user to purchase the particular item.
Also when the user tries to sale items which are not in stock, the system will prompt the user that the stock is not enough. Customers of this system can search for a automobile; can purchase a automobile easily by selecting fast. On the other hand the stock of automobiles can be maintained perfectly by the automobile shop manager overcoming the drawbacks of existing system.
CFD Simulation of By-pass Flow in a HRSG module by R&R Consult.pptxR&R Consult
CFD analysis is incredibly effective at solving mysteries and improving the performance of complex systems!
Here's a great example: At a large natural gas-fired power plant, where they use waste heat to generate steam and energy, they were puzzled that their boiler wasn't producing as much steam as expected.
R&R and Tetra Engineering Group Inc. were asked to solve the issue with reduced steam production.
An inspection had shown that a significant amount of hot flue gas was bypassing the boiler tubes, where the heat was supposed to be transferred.
R&R Consult conducted a CFD analysis, which revealed that 6.3% of the flue gas was bypassing the boiler tubes without transferring heat. The analysis also showed that the flue gas was instead being directed along the sides of the boiler and between the modules that were supposed to capture the heat. This was the cause of the reduced performance.
Based on our results, Tetra Engineering installed covering plates to reduce the bypass flow. This improved the boiler's performance and increased electricity production.
It is always satisfying when we can help solve complex challenges like this. Do your systems also need a check-up or optimization? Give us a call!
Work done in cooperation with James Malloy and David Moelling from Tetra Engineering.
More examples of our work https://www.r-r-consult.dk/en/cases-en/
Forklift Classes Overview by Intella PartsIntella Parts
Discover the different forklift classes and their specific applications. Learn how to choose the right forklift for your needs to ensure safety, efficiency, and compliance in your operations.
For more technical information, visit our website https://intellaparts.com
Welcome to WIPAC Monthly the magazine brought to you by the LinkedIn Group Water Industry Process Automation & Control.
In this month's edition, along with this month's industry news to celebrate the 13 years since the group was created we have articles including
A case study of the used of Advanced Process Control at the Wastewater Treatment works at Lleida in Spain
A look back on an article on smart wastewater networks in order to see how the industry has measured up in the interim around the adoption of Digital Transformation in the Water Industry.
Immunizing Image Classifiers Against Localized Adversary Attacksgerogepatton
This paper addresses the vulnerability of deep learning models, particularly convolutional neural networks
(CNN)s, to adversarial attacks and presents a proactive training technique designed to counter them. We
introduce a novel volumization algorithm, which transforms 2D images into 3D volumetric representations.
When combined with 3D convolution and deep curriculum learning optimization (CLO), itsignificantly improves
the immunity of models against localized universal attacks by up to 40%. We evaluate our proposed approach
using contemporary CNN architectures and the modified Canadian Institute for Advanced Research (CIFAR-10
and CIFAR-100) and ImageNet Large Scale Visual Recognition Challenge (ILSVRC12) datasets, showcasing
accuracy improvements over previous techniques. The results indicate that the combination of the volumetric
input and curriculum learning holds significant promise for mitigating adversarial attacks without necessitating
adversary training.
Water scarcity is the lack of fresh water resources to meet the standard water demand. There are two type of water scarcity. One is physical. The other is economic water scarcity.
Democratizing Fuzzing at Scale by Abhishek Aryaabh.arya
Presented at NUS: Fuzzing and Software Security Summer School 2024
This keynote talks about the democratization of fuzzing at scale, highlighting the collaboration between open source communities, academia, and industry to advance the field of fuzzing. It delves into the history of fuzzing, the development of scalable fuzzing platforms, and the empowerment of community-driven research. The talk will further discuss recent advancements leveraging AI/ML and offer insights into the future evolution of the fuzzing landscape.
Final project report on grocery store management system..pdfKamal Acharya
In today’s fast-changing business environment, it’s extremely important to be able to respond to client needs in the most effective and timely manner. If your customers wish to see your business online and have instant access to your products or services.
Online Grocery Store is an e-commerce website, which retails various grocery products. This project allows viewing various products available enables registered users to purchase desired products instantly using Paytm, UPI payment processor (Instant Pay) and also can place order by using Cash on Delivery (Pay Later) option. This project provides an easy access to Administrators and Managers to view orders placed using Pay Later and Instant Pay options.
In order to develop an e-commerce website, a number of Technologies must be studied and understood. These include multi-tiered architecture, server and client-side scripting techniques, implementation technologies, programming language (such as PHP, HTML, CSS, JavaScript) and MySQL relational databases. This is a project with the objective to develop a basic website where a consumer is provided with a shopping cart website and also to know about the technologies used to develop such a website.
This document will discuss each of the underlying technologies to create and implement an e- commerce website.
Hybrid optimization of pumped hydro system and solar- Engr. Abdul-Azeez.pdffxintegritypublishin
Advancements in technology unveil a myriad of electrical and electronic breakthroughs geared towards efficiently harnessing limited resources to meet human energy demands. The optimization of hybrid solar PV panels and pumped hydro energy supply systems plays a pivotal role in utilizing natural resources effectively. This initiative not only benefits humanity but also fosters environmental sustainability. The study investigated the design optimization of these hybrid systems, focusing on understanding solar radiation patterns, identifying geographical influences on solar radiation, formulating a mathematical model for system optimization, and determining the optimal configuration of PV panels and pumped hydro storage. Through a comparative analysis approach and eight weeks of data collection, the study addressed key research questions related to solar radiation patterns and optimal system design. The findings highlighted regions with heightened solar radiation levels, showcasing substantial potential for power generation and emphasizing the system's efficiency. Optimizing system design significantly boosted power generation, promoted renewable energy utilization, and enhanced energy storage capacity. The study underscored the benefits of optimizing hybrid solar PV panels and pumped hydro energy supply systems for sustainable energy usage. Optimizing the design of solar PV panels and pumped hydro energy supply systems as examined across diverse climatic conditions in a developing country, not only enhances power generation but also improves the integration of renewable energy sources and boosts energy storage capacities, particularly beneficial for less economically prosperous regions. Additionally, the study provides valuable insights for advancing energy research in economically viable areas. Recommendations included conducting site-specific assessments, utilizing advanced modeling tools, implementing regular maintenance protocols, and enhancing communication among system components.
TECHNICAL TRAINING MANUAL GENERAL FAMILIARIZATION COURSEDuvanRamosGarzon1
AIRCRAFT GENERAL
The Single Aisle is the most advanced family aircraft in service today, with fly-by-wire flight controls.
The A318, A319, A320 and A321 are twin-engine subsonic medium range aircraft.
The family offers a choice of engines
Vaccine management system project report documentation..pdfKamal Acharya
The Division of Vaccine and Immunization is facing increasing difficulty monitoring vaccines and other commodities distribution once they have been distributed from the national stores. With the introduction of new vaccines, more challenges have been anticipated with this additions posing serious threat to the already over strained vaccine supply chain system in Kenya.
Saudi Arabia stands as a titan in the global energy landscape, renowned for its abundant oil and gas resources. It's the largest exporter of petroleum and holds some of the world's most significant reserves. Let's delve into the top 10 oil and gas projects shaping Saudi Arabia's energy future in 2024.
Top 10 Oil and Gas Projects in Saudi Arabia 2024.pdf
Mathematical Analysis of Gaseous Reduction of Fe2O3-MnO2- SiO2Mixed Oxides
1. International journal of scientific and technical research in engineering (IJSTRE)
www.ijstre.com Volume 1 Issue 2 ǁ May 2016.
Manuscript id.37142828 www.ijstre.com Page 11
Mathematical Analysis of Gaseous Reduction of Fe2O3-MnO2-
SiO2Mixed Oxides
Saeed Ghali1
, Elsayed Mousa 2,3*
1
Assoc. Prof. at Steel and Ferroalloys Department, CentralMetallurgical Research and Development Institute
(CMRDI)Postal Address: P.O Box 87, Helwan, Egypt
E-Mail: a3708052@yahoo.com
2
Researcher at Process Integration Department,Swerea MEFOS, P.O. Box 812, 97125 Luleå, Sweden
3
Researcher at Pyrometallurgy Department, CentralMetallurgical Research and Development Institute
(CMRDI)Postal Address: P.O Box 87, Helwan, Egypt
* Corresponding authors, E-Mail: mousa71@yahoo.com
ABSTRACT:Low grade iron ores are often contaminated with relatively high percentage of different
impurity gangue minerals. The iron ores contaminated with manganese oxide and silica are hardly reducible
and consume more energy in the integrated steel plant. Therefore it is important to estimate and predict the
influence of manganese oxide, silica and temperature on the reduction yield of iron oxide using mathematical
model approach. In the current study, a 23
(three-parameters, two-levels)factorial design is applied on the
gaseous reduction experimental data of mixed oxides (Fe2O3-MnO2-SiO2) to build a linear regression model.
The calculations have been performed using Matlab program. The developed mathematical model indicated that
SiO2 and temperature have positive effect on the reduction yield of iron oxide. On the other hand, MnO2
exhibited the highest negative impact on the reduction yield of iron oxide followed by the interaction coefficient
of MnO2, SiO2 and temperature. The results of the developed mathematical model are fitted to the experimental
reduction data of mixed oxides.
Keywords:factorial design; modelling; mixed oxides; gaseous reduction; mathematical analysis
I. Introduction
The quality of iron ore is a crucial factor that affecting the product quality, production rate and total cost of
final steel product. The intensive mining of iron ores over many decades has resulted in a depletion of the high
grade resources and increased its prices in the global market. Recently, utilization of low and medium grade iron
ores became necessary in steel industry to overcome the shortage of the high grade ores. In addition, intensive
work is being done to efficiently recycle iron waste materials which are generated in the integrated steel plants.
The Egyptian iron ores are classified as low to medium grade ores which are often contaminated with relatively
high percentage of manganese oxide (0.03-13.7%) and silica (0.07-13.7%) beside many other residues [1].
These impurities have a negative impact on the steel production rate and resulted in high energy consumption,
low product quality and high production cost. Intensive experimental work has been carried out to evaluate the
reduction kinetics and mechanism of SiO2-MnO2 doped Fe2O3 compacts [2-5]. The reduction rate was enhanced
by SiO2 at the beginning while reduction retardation appeared at the final stages. This was attributed to the
formation of low reducible fayalite (Fe2SiO4) phase. In MnO2-SiO2-doped Fe2O3 compacts, the reduction rate
was greatly hindered due to the formation of hard reducible fayalitemanganoan [(Fe,Mn)2SiO4]. The behavior of
manganese oxides during magnetizing reduction of Baharia iron ore by CO/CO2 gas mixtures at 600-1000o
C
was studied [6]. It was found that the reduction of MnO2is stopped at MnO phase. The reduction of mixed iron-
manganese oxides in H2 and CO atmosphere indicated that the presence of manganese oxide has slowed the
reduction rate of iron oxide [7]. The kinetics of hydrogen reduction of iron-manganese mixed oxides and the
carbothermic reduction of MnFe2O4have been investigated [8]. The reduction with H2 in absence of carbon led
to the formation of an intermediate product between MnO and FeO at 507o
C which has been finally reduced to
MnO and metallic Fe. In presence of carbon, methane was formed at 800o
C and decomposed at about 1050o
C to
nascent carbon which accelerated the reduction process. The reduction behaviour of high manganese iron ore
(9.9 wt.% MnO2) by H2 at 800-1000o
C has been investigated [9]. The reduction rate was increased with
temperature and decreased as the time proceeded.
The previous survey summarized various investigations which have been conducted experimentally to
estimate the effect of manganese oxide and silica on the reduction rate of iron oxides. However, the effective
magnitude of these oxides on the reduction rate of iron oxides at different temperature is still required.
Moreover, the influence of the interaction of different parameters on the reduction yield of iron oxide is difficult
to be experimentally evaluated. The statistical analysis is able to precisely estimate the effect of each individual
2. Mathematical Analysis of Gaseous Reduction of Fe2O3-MnO2-SiO2 Mixed Oxides
Manuscript id. 37142828 www.ijstre.com Page 12
parameter and its interaction with the other parameters on the reduction yield of iron oxide. A regression model
has been developed based on factorial design approach. The factorial design has several advantages such as
prediction of process yield and process performance and it can be also modified for further applications in the
iron and steel making processes [10-15]. In the current study, a 23
(three-parameters, two-levels) factorial design
is used to investigate the impact of MnO2, SiO2 and temperature on the reduction yield of iron oxide. The
interaction coefficient between mixed oxides and temperature is statistically analysed.
II. Materials and Methodology
A23
factorial design has been applied on the experimental data of pure Fe2O3and its mixture with MnO2 and
SiO2. The reduction was conducted with CO at various temperatures [3]. Chemically high grades (> 99.5%)
Fe2O3, MnO2 and SiO2 powders (< 50 µm) were used to eliminate the influence of any other impurities that are
usually associated with iron ores. The additions of MnO2 and/or SiO2 to Fe2O3 were 6.0 and 7.5 wt.%
respectively. These values have been used to simulate the average of MnO2 and SiO2 percentage in the Egyptian
iron ores. The powders are mixed in a ball mill for 8.0 hours to attain a complete homogeneous mixture. The
oxides mixtures are moistened with 6 wt.% naphtha and then pressed in a cylindrical mould at 10 kN. The dry
compacts (9.0 mm diameter, 14 mm height) are gradually heated in a muffle furnace (10 K/min) up to 1200o
C
and kept at this temperature for 6.0 hours. After firing, the compacts are gradually cooled down to room
temperature to avoid the thermal shock. Pure Fe2O3 and mixed oxides (Fe2O3-MnO2-SiO2) compacts were
isothermally reduced with pure CO gas (1.0 l/min) at 800-1100o
C. The reduction trial shave been conducted in
tube furnace as can be schematically shown in Figure 1. The system consists of an automatic sensitive balance
(B) equipped with a vertical tube furnace (F). An alumina reaction tube (A) was fitted inside the furnace. The
output of the balance (O) is connected to the recording system (R) for continuous measurement of weight loss
during the reduction as a function of time until the compact weight becomes constant. The flow rate of CO gas
is adjusted using flow meter (D). The actual temperatures of the furnace (T1) and sample (T2) are measured
with controller (K).Purified N2 at constant flow rate of 1.0 l/min is introduced in the reaction tube during the
heating up of the furnace to the predetermined temperature. At the applied temperature, the compact (S) is
placed in a platinum basket (P) and is suspended from the balance arm by a platinum wire (W). The compact is
positioned in the middle hot zone of the tube furnace. After soaking the sample at the ambient temperature for
10 min, CO gas is applied for the reduction of sinter. When the sample weight becomes constant, the reducing
gas is stopped and pure N2purged in the reaction tube then the reduced compact is pulled up to the cooled zone
of the reaction tube and quickly dropped out in a conical flask containing acetone to prevent the re-oxidation.
Figure 1. Schematic diagram of the reduction system
3. Mathematical Analysis of Gaseous Reduction of Fe2O3-MnO2-SiO2 Mixed Oxides
Manuscript id. 37142828 www.ijstre.com Page 13
The experimental reduction behaviour of pure Fe2O3 and mixed oxides are discussed elsewhere [3]. In
the current study, a 23
factorial design is applied on the experimental data of the reduction trails. The reduction
yield of pure Fe2O3 and mixed oxides compacts after 20 min at 800o
C and 900o
C is given in Table 1. The
reduction yield is determined depending on the reducible oxygen in the sample as given in Eq. 1.
𝑅𝑒𝑑𝑢𝑐𝑡𝑖𝑜𝑛 𝑦𝑖𝑒𝑙𝑑 % =
𝑊1 − 𝑊2
𝑊𝑜
∗ 100 (1)
where: W1 is the weight of the sample before reduction, W2 is the weight of sample after reduction and Wo is
theweight of reducible oxygen.
Table 1.Conditions of experiments and reduction yield of iron oxide
Trail
No.
MnO2,
wt. %
SiO2,
wt. %
Fe2O3,
wt. %
Temperature,
o
C
Reduction yield of iron oxide, %
1st
2nd
1 0 0 Rest 800 39.9 40.1
2 6 0 Rest 800 33.5 33.6
3 0 7.5 Rest 800 44.9 45.1
4 6 7.5 Rest 800 34.8 35.2
5 0 0 Rest 900 41.5 41.7
6 6 0 Rest 900 37.7 37.9
7 0 7.5 Rest 900 48.0 48.2
8 6 7.5 Rest 900 33.4 33.6
The experiments have been conducted two times under the same conditions and the reduction yield
has been calculated. A 23
factorial design is applied to evaluate the effect of MnO2, SiO2 and temperature on the
reduction yield. Mathematical analysis of MnO2, SiO2, temperature and their interactions effect on the reduction
of iron oxide is addressed. Regression model is formulated based on the factorial design approach to calculate
the reduction yield in terms of MnO2, SiO2 and applied temperature.
III. Results and Discussion
3.1. Definition of the controlling parameters
The controlling parameters which are considered in the applied 23
factorial design are including the effect of
MnO2 and SiO2 as well as the effect of temperature on reduction process of iron oxide.
By convention, the effect of a factor was donated by a capital Latin letter. Thus “A” refers to the effect of
MnO2, “B” refers to the effect of SiO2, “C” refers to the effect of reduction temperature, “AB” refers to the
interaction effect of MnO2 and SiO2, “AC” refers to interaction effect of MnO2 and temperature, “BC” refers to
the interaction effect of SiO2 and temperature, while “ABC” refers to the interaction effect of MnO2, SiO2 and
temperature. The low and high levels of A, B and C are denoted by “–“and “+” respectively. The eight treatment
combinations in the design are usually represented by lowercase letters. The high level of any factor in the
treatment combination is denoted by the corresponding lowercase letter (a, b, c, ab, ac, bc and abc), while the
low level of any factor will be indicated by the absence of its corresponding letter. Thus, “a” represents the
treatment combination of A at high level when B and C at low levels, “b” represents B at high level when A and
B at low levels, “ab” represents A and B factors at the high levels when C at low level, “abc” represents A, B
and C factors at the high levels, finally (1) is used to denote all factors at low level. The average effect of any
factor can be defined as the change in response which is produced by changing the factor level divided by the
averaged levels of the other factors. The symbols (1), a, b, ab, c, ac, bc, abc represent the total of all 2 replicates
which have been taken at the treatment combination i.e. (n=2).
3.2 Mathematical formulations
Mathematical formulations are used to estimate the effect of different parameters on the reduction yield. The
effect of A at low level of B and C is [a-(1)]/n, the effect of A at high level of B and C is [abc-bc]/n, the effect
of A at low level of B and high level of C is [ac-c]/n and the effect of A at high level of B and low level of C is
[ab-b]/n. The main effect of A is the average values of its effect at low and high levels of B and C as given in
Eq. 2.
𝐴 =
1
4𝑛
[ 𝑎 + 𝑎𝑏 + 𝑎𝑐 + 𝑎𝑏𝑐 − 1 + 𝑏𝑐 + 𝑐 + 𝑏 ] (2)
The average effect of B and C can be calculated by the same manner of A as given in Eqs. 3 and 4 respectively.
𝐵 =
1
4𝑛
[ 𝑏 + 𝑎𝑏 + 𝑏𝑐 + 𝑎𝑏𝑐 − 1 + 𝑎 + 𝑎𝑐 + 𝑐 ] (3)
𝐶 =
1
4𝑛
[ 𝑐 + 𝑎𝑐 + 𝑏𝑐 + 𝑎𝑏𝑐 − 1 + 𝑎 + 𝑏 + 𝑎𝑏 ] (4)
4. Mathematical Analysis of Gaseous Reduction of Fe2O3-MnO2-SiO2 Mixed Oxides
Manuscript id. 37142828 www.ijstre.com Page 14
The binary interaction effects of the factors A and B represented in AB is one half of the difference
between the averages effect of factor A at the two levels of factor B. The average effect of factor A at high level
of factor B is [(abc-bc)+(ab-b)]/2n, and the average effect of factor A at low level of factor B is [(ac-c)+(a-
(1))]/2n. Based on this the binary interaction AB effect can be given in Eq. 5.
𝐴𝐵 =
1
4𝑛
𝑎𝑏𝑐 + 𝑎𝑏 + 𝑐 + 1 − 𝑏𝑐 + 𝑏 + 𝑎𝑐 + 𝑎 (5)
In similar way, the average binary interaction effect of AC and BC can be calculated as give in Eqs. 6 and 7
respectively.
𝐴𝐶 =
1
4𝑛
𝑎𝑏𝑐 + 𝑎𝑐 + 𝑏 + 1 − 𝑎𝑏 + 𝑐 + 𝑏𝑐 + 𝑎 (6)
𝐵𝐶 =
1
4𝑛
𝑎𝑏𝑐 + 𝑏𝑐 + 𝑎 + 1 − 𝑎𝑐 + 𝑏 + 𝑎𝑏 + 𝑐 (7)
The ternary interaction effects of factor A, B, and C represented in ABC is defined as the average difference
between binary interaction effects ABat two different levels of C as given in Eqs. 8 and 9.
𝐴𝐵𝐶 =
1
4𝑛
(𝑎𝑏𝑐 − 𝑏𝑐) − 𝑎𝑐 − 𝑐 − 𝑎𝑏 − 𝑏 + (𝑎 − 1 ) (8)
𝐴𝐵𝐶 =
1
4𝑛
𝑎𝑏𝑐 + 𝑐 + 𝑏 + 𝑎 − (𝑏𝑐 + 𝑎𝑐 + 𝑎𝑏 + 1 ) (9)
3.3 Application of factorial design
Plus and minus signs that can be developed from the contrasts are summarized in Table 2. The high level is
referred by plus sign and low level is referred by minus sign. The signs of identity element are plus.
Table 2. Algebraic signs for calculating effects in the 23
Design
Treatment
combination
Factorial Effect
I A B AB C AC BC ABC
(1) + - - + - + + -
a + + - - - - + +
b + - + - - + - +
ab + + + + - - - -
c + - - + + - - +
ac + + - - + + - -
bc + - + - + - + -
abc + + + + + + + +
Sum of squares (SS) for the effect of parameters in 23
factorial design with n replicates is
SS=(contrast)2
/8n. The total sum of squares (SST) has (abcn-1) degree of freedom while the error sum of
squares (SSE) has abc(n-1) degree of freedom. It can be calculated by using Eqs. 10 and 11 respectively. The
avearge effect of the different parameters and their interactions are calculated and given in Table 3.Thesum of
squares, mean square and the absolute magnitude effect is given in Table 4.
𝑆𝑆 𝑇 = 𝑦𝑖𝑗𝑘
2𝑛
𝑛=1
2
𝑘=1
2
𝑗=1
2
𝑖=1 −
𝑦…2
4𝑛
(10)
𝑆𝑆 𝐸 = 𝑆𝑆 𝑇 − 𝑆𝑆𝐴 − 𝑆𝑆 𝐵 − 𝑆𝑆 𝐶−𝑆𝑆𝐴𝐵 − 𝑆𝑆𝐴𝐶 − 𝑆𝑆 𝐵𝐶 − 𝑆𝑆𝐴𝐵𝐶 (11)
Table 3. Values of the average effect of all parameters
Trail
No.
Effective Parameter Variant Average of
reduction
yield, %
No. of
applied
equation
Average effect
of parameters
1 (1) (1) 40 --- ---
2 A (MnO2%) a 33.55 2 -8.7125
3 B (SiO2%) b 45 3 2.1625
4 AB (MnO2% &
SiO2%)
ab 35 4 1.8625
5. Mathematical Analysis of Gaseous Reduction of Fe2O3-MnO2-SiO2 Mixed Oxides
Manuscript id. 37142828 www.ijstre.com Page 15
5 C (Temperature) c 41.6 5 -3.5875
6 AC (MnO2&
Temperature)
ac 37.8 6 -0.4875
7 BC (SiO2% &
Temperature
bc 48.1 7 -1.0625
8 ABC (MnO2% &
SiO2% &
Temperature)
abc 33.5 9 -1.8125
Table 4. Analysis of variances
Source of
Variance
Average
Effect
Sum of
Square (SS)
Degree of
Freedom
Mean Square
MS
Fo (magnitude
effect)
A (MnO2%) -8.7125 303.6306 1 303.6306 11849
B (SiO2%) 2.1625 18.70563 1 18.70563 729.9756
C (Temp.) 1.8625 13.87563 1 13.87563 541.4878
AB -3.5875 51.48063 1 51.48063 2009
AC -0.4875 0.950625 1 0.950625 37.09756
BC -1.0625 4.515625 1 4.515625 176.2195
ABC -1.8125 13.14063 1 13.14063 512.8049
Error ----- 0.205 8 0.025625 ---
Total ----- 406.5044 15 --- ---
From the previous calculations, the magnitude and direction of the factors can be examined to
determine which variable is important and more effective. The main effect of A is negative with large
magnitude. This means that the higher MnO2% in the oxide mixture, the lower reduction yield is. Also, it is
clear that the main effect of B is positive with relatively large magnitude comparedwith the magnitude of C.
This means that SiO2 has a significant positive effect on reduction yield of iron oxide. Temperature has positive
effect with small magnitude on the reduction yield compared to that of SiO2. On the other hand, the effect of the
interaction combination of AB (MnO2 and SiO2) is negative with relatively large magnitude. This means that the
increasing both of SiO2 and MnO2in the mixed oxide mixture affects negatively the reduction yield. The
interaction combination of BC (SiO2 with temperature) and AC (MnO2 with temperature) are negative with
relatively small magnitude. This indicates that SiO2 with temperature and MnO2 with temperature are retarded
the reduction process of iron oxide for a certain extent. Finally, the interaction combination of the three factors
ABC (MnO2, SiO2, and temperature) is negative with relatively high magnitude. This indicates that the high
levels of MnO2, SiO2 and temperature are retarded the reduction rate of iron oxide.
The contrast coefficient has been used to estimate the effect of the individual and interacted parameters
as summerized in Table 5. The contrast coefficient is either (+1) or (-1) referring to the maximum and minimum
level of the parameter respectively.
Table 5. Contrast coefficients of effects
Effects (1) a b ab c ac bc abc
A -1 +1 -1 +1 -1 +1 -1 +1
B -1 -1 +1 +1 -1 -1 +1 +1
AB +1 -1 -1 +1 +1 -1 -1 +1
C -1 -1 -1 -1 +1 +1 +1 +1
AC +1 -1 +1 -1 -1 +1 -1 +1
BC +1 +1 -1 -1 -1 -1 +1 +1
ABC -1 +1 +1 -1 +1 -1 -1 +1
6. Mathematical Analysis of Gaseous Reduction of Fe2O3-MnO2-SiO2 Mixed Oxides
Manuscript id. 37142828 www.ijstre.com Page 16
The results of the experimental trails can be expressed in terms of regression model as given in Eq.
12.
𝑦 = 𝛽0 + 𝛽1 𝑥1 + 𝛽2 𝑥2 + 𝛽3 𝑥3 + 𝛽12 𝑥1 𝑥2 + 𝛽13 𝑥1 𝑥3 + 𝛽23 𝑥2 𝑥3 + 𝛽123 𝑥1 𝑥2 𝑥3 + 𝜖(12)
Where: x1,x2 and x3 are coded variables that represent the MnO2%, SiO2% and temperature respectively and
𝛽𝑠
,
are regression coefficients.𝛽0 is the intercept which is the grand average of all 16 observations
(i.e.𝛽0=39.31875), the regression coefficients𝛽1, 𝛽2 and 𝛽3are one-half the corresponding factors A, B, and C
respectively (β1= -4.35625, 𝛽2= 1.08125 &𝛽3= 0.93125), the regression coefficients 𝛽12, 𝛽13, 𝛽23 and 𝛽123 are
one-half the corresponding factors AB, AC, BC and ABC respectively which are (β12= -1.79375, β13= -
0.24375, β23= -0.53125 &𝛽123 =-.0.90625) and 𝜖 is the residual (the difference between observed and fitted
point of the design). Based on this values, Eq. 12 can be modified as given in Eq. 13.
𝑅𝑒𝑑𝑢𝑐𝑡𝑖𝑜𝑛 𝑦𝑖𝑒𝑙𝑑 = 39.31875 − 4.35625𝑥1 + 1.08125𝑥2 + 0.93125𝑥3 − 1.79375𝑥1 𝑥2 − 0.224375𝑥1 𝑥3 −
0.53125𝑥2 𝑥3 − 0.90625𝑥1 𝑥2 𝑥3 + 𝜖 (13)
To calculate the predicted reduction yield and to estimate the residual (𝜖) at (1), a, b, c, ab, ac, bc and abc; the
sign of coded variables have been taken from Table 2. The resuts are presented in Table 6. The average
residence is ± 0.10625 which can be neglicted.
Table 6. Actual and predicted reduction yield at different conditions
The relation between the natural and coded variables can be defined as follow: the coded variable is equal to
[(natural variable – 1/2(variable at high level + variable at low level)) / 1/2(variable at high level + variable at
low level)]. Based on this concept the reduction yield can be predicted in terms of MnO2 and SiO2 concentration
with temperature as given in Eq. 14.
𝑅𝑒𝑑𝑢𝑐𝑡𝑖𝑜𝑛 𝑦𝑖𝑒𝑙𝑑 =
35.2144 + 0.0066𝑇 − 0.9483 𝑆𝑖𝑂2% − 7.2798 𝑀𝑛𝑂2% + 1.215 𝑀𝑛𝑂2% 𝑆𝑖𝑂2% +
0.0075𝑇 𝑀𝑛𝑂2% + 0.002𝑇 𝑆𝑖𝑂2% − 0.0016𝑇 𝑀𝑛𝑂2% 𝑆𝑖𝑂2%
(14)
where; T is the temperature in o
C
This equation covering the concentration of MnO2 and SiO2form 0 to 6.0% and from 0 to 7.5% respectively
within temperature range 800-900o
C. This full regression formulation indicates that the reduction yield is not
only dependent on the individual parameter (MnO2, SiO2, or temperature) but also on the mutual interactions
between all of these parameters.
3.4 Validation of regression model
In order to verify the previously described regression model, the reduction yield has been calculated using the
coded and the actual variables of mixed oxides. The results are compared to that of experimetal results as can be
seen in Figure 2. It can be seen that the calculated reduction yield is very close to that of the experimental
Variable
Predicted
reduction
yield, %
Actual
reduction
yield, %
Residence
( )
The
residence
variation
1st
2nd
1st
2nd
(1) 40.002 39.9 40.100 -0.102 0.098 ± 0.1
a 33.548 33.5 33.600 -0.048 0.052 ± 0.05
b 45.002 44.9 45.100 -0.102 0.098 ± 0.1
ab 34.998 34.8 35.200 -0.198 0.202 ± 0.2
c 41.598 41.5 41.700 -0.098 0.102 ± 0.1
ac 37.802 37.7 37.900 -0.102 0.098 ± 0.1
bc 48.098 48 48.200 -0.098 0.102 ± 0.1
abc 33.502 33.4 33.600 -0.102 0.098 ± 0.1
7. Mathematical Analysis of Gaseous Reduction of Fe2O3-MnO2-SiO2 Mixed Oxides
Manuscript id. 37142828 www.ijstre.com Page 17
values. The maximum reduction yield is obtained at the highest concentration of SiO2 (7.5% wt.%) at 900o
C
while the lowest reduction is demonstrated at the highest MnO2 level (6.0 wt.%) at 800o
C.
Figure 2. Actual and predicted reduction yield by using actual and coded variables
The effect of MnO2 and SiO2 on the reduction yield of Fe2O3 at 800o
C and 900o
C is given in Figure
3 and Figure 4 respectively. In both cases, the maximum reduction yiled is exhibited by Fe2O3 mixed with 7.5
wt.% SiO2. On the other hand, the iron oxide mixed with 6 wt.% MnO2 showed the lowest reduction yield at
800o
C. At 900o
C, the lowest reduction yield at 900o
C is demonstrated by the iron oxide mixed with 6 wt.%
MnO2 and 7.5 wt.% SiO2.
Figure 3. Actual and predicted reduction yield at 800o
C
0
10
20
30
40
50
Pure
Fe₂O₃
6 wt-%
MnO₂
7.5 wt-%
SiO₂
6 wt-%
MnO₂ + 7.5
wt-% SiO₂
RD,%
Predicted Actual 1st reading Actual 2nd reading
8. Mathematical Analysis of Gaseous Reduction of Fe2O3-MnO2-SiO2 Mixed Oxides
Manuscript id. 37142828 www.ijstre.com Page 18
Figure 4. Actual and predicted reduction yield at 900o
C
In order to examine the efficiency of the derived model, the mathematical formula which is given in
Eq. 12 has been applied at different percentages of MnO2 (0, 2, 4, and 6 wt-%), SiO2 (0, 2.5, 5, and 7.5 wt-%)
and mixture of SiO2 (7,5 wt-%) with (0, 2, 4, and 6 wt-%) MnO2. The results are compared to that obtained by
the experimental work at 800 and 900o
C as shwon in Figures 5 and 6 respectively. It can be seen that, in many
cases, the calculated values of reduction yield are in a good agreement with that obtained by the experimental
trails. This reveals that the factorial design is very usefull approach for staistaical analysis of the factors that
affecting the reduction yield of iron oxide. The developed regerssion model is able to predict the reduction yield
of iron oxide as a function of chemical composition and temperaure which makes it very effective in saving time
and production cost.
Figure 5. Comparison between the experimental and calculated reduction yield at 800o
C
under the influence of (a) MnO2 (b) SiO2 (c) MnO2 + SiO2
a b
c
9. Mathematical Analysis of Gaseous Reduction of Fe2O3-MnO2-SiO2 Mixed Oxides
Manuscript id. 37142828 www.ijstre.com Page 19
Figure 6. Comparison between the experimental and calculated reduction yield at 900o
C
under the influence of (a) MnO2 (b) SiO2 (c) MnO2 + SiO2
IV. Conlcusions
A 23
(three-parameters, two-levels) factorial experimental design has been implemented to analyse the reduction
data of iron oxide compacts mixed with 6.0 wt.% MnO2, 7.5 wt.% SiO2 and 6.0% MnO2+7.5% MnO2.The
reduction process of pure Fe2O3 and mixed oxides (Fe2O3-MnO2-SiO2) was carried out by CO at 800-900o
C and
the reduction degree was considered at 20 minutes. The main finding can be summarized in the following
points:
(1) A regression model is developed based on an experimental design approach to calculate the reduction
yield: 𝑅𝑒𝑑𝑢𝑐𝑡𝑖𝑜𝑛 𝑦𝑖𝑒𝑙𝑑 = 35.2144 + 0.0066𝑇 − 0.9483 𝑆𝑖𝑂2% − 7.2798 𝑀𝑛𝑂2% +
1.215 𝑀𝑛𝑂2% 𝑆𝑖𝑂2% + 0.0075𝑇 𝑀𝑛𝑂2% + 0.002𝑇 𝑆𝑖𝑂2% − 0.0016𝑇 𝑀𝑛𝑂2% 𝑆𝑖𝑂2%
(2) The SiO2 content in the oxide mixtures showed the highest positive effect on the reduction yield while
MnO2 exhibited the highest negative effect on the reduction of iron oxide.
(3) The interaction combination of the three parameters (MnO2, SiO2, and temperature) was demonstrated
relatively high negative impact on the reduction yield of iron oxide.
(4) The calculated values of reduction yield using the developed regression model were found in a good
agreement with that obtained by experimental trails. This confirms that the factorial design can be
successfully implemented to evaluate the effect of different parameters on the production yield in the
metallurgical processes.
References
[1] H.M. Baioumy, M.Z. Khedr, and A.H. Ahmed, “Mineralogy geochemistry andorigin of Mn in the high-
Mn ironores, Bahariya Oasis, Egypt”, Ore Geology Reviews,vol. 3, No. 12, pp. 63-67, 2013.
[2] A.A. El-Geassy, M.I. Nasr, A.A. Omar, and E.A. Mousa, “Reduction kinetics and catastrophic swelling
of MnO2-doped Fe2O3 compacts with CO at 1073-1373K”, ISIJ International, vol. 47, No. 3, pp. 377-
385, 2007.
[3] A.A. El-Geassy, M.I. Nasr, A.A. Omar, and E.A. Mousa, “Influence of SiO2 and/or MnO2 on the
reductionbehaviour and structure changes of Fe2O3 compacts with CO gas”, ISIJ International, vol. 48,
No. 10, pp. 1359-1367, 2008.
c
a b
10. Mathematical Analysis of Gaseous Reduction of Fe2O3-MnO2-SiO2 Mixed Oxides
Manuscript id. 37142828 www.ijstre.com Page 20
[4] A.A. El-Geassy, M.I. Nasr, A.A. Omar, and E.A. Mousa, “Isothermal reduction behaviour of MnO2
doped Fe2O3compacts with H2 at 1073-1373”, Ironmaking andSteelmaking, vol. 35, No. 7, pp. 531-538,
2008.
[5] A.A. El-Geassy, M.I. Nasr, and E.A. Mousa, “Influence of manganese oxide and silica on the
morphological structure of hematite compacts”, Steel Research International, vol. 81, No. 3, pp. 178-
185, 2010.
[6] A.A. El-Geassy, M.I. Nasr, M.A. Yousef, M.H. Khedr, and M. Bahgat, “Behaviour of manganese oxides
duringmagnetising reduction of Baharia iron ore by CO–CO2gas mixture”, Ironmaking and Steelmaking,
vol. 27, No.2,pp. 117-122, 2000.
[7] I.R. Leith, I.R., and M.G. Howden, “Temperature-programmed reduction of mixed iron-manganese
oxidecatalysts in hydrogen and carbon monoxide, Applied Catalysis, vol. 37, No. 1-2, pp. 75-92, 1988.
[8] T. Hashizume, K. Terayama, T. Shimazaki, H. Itoh, and Y. Okumo, “Reduction of MnFe2O4 without and
withcarbon; simultaneous measurements of humidity sensor and evolved gas analysis”, Journal of
Thermal Analysisand Calorimetry, vol. 69, pp. 1045-1050, 2002.
[9] A.M. Ahmed, A.A. El-Geassy, and M.L. Mishreky, “Crude steel directly from pre-reduced high
manganesecontaining iron ore, Ironmaking and Steelmaking, vol. 42, No. 3, pp. 161-168, April 2015.
[10] Y. Gao, H.G. Kim, H.Y. Sohn, and C.W. Kim, “Gaseous pre-reduction for the magnetic beneficiation
offerruginous low-grade Mn Ore, ISIJ International, vol. 52, No. 5, pp. 759-763, 2012.
[11] T.J. Mesquita, R.P. Nogueira, and I.N. Bastos, “Factorial design applied to corrosion of super duplex
stainless steel, Latin America Applied Research, vol. 41, pp. 311-315, 2011.
[12] R. Robinson, “Studies in low temperature self-reduction of by-products from integrated iron and
steelmaking”, PhD thesis, Luleå University of Technology, Luleå, 2008. ISSN: 1402-1544.
[13] S. Ghali, E.A. Mousa, “Mathematical analysis of the effect of iron and silica on the reduction
performance of manganese ores”, Journal of Metallurgy, vol. 2015,
2015.http://dx.doi.org/10.1155/2015/679306
[14] E.A. Mousa, “Mathematical analysis of the reduction of wüstite at different basicity using factorial
design”,Journal of Metallurgy, vol. 2014, 2014. http://dx.doi.org/10.1155/2014/201659
[15] S. Ghali, E.A. Mousa, “Analysis of the reduction yield of synthetic iron oxide sinter reduced by H2 at
900-1100°C using factorial design approach”, Steel Grips, Online paper: http://www.steel-
grips.com/index.php/en/articles/25-