scholarly journals Oxidation-Enhanced Evaporation in High-Carbon Ferromanganese

2021 ◽  
Author(s):  
Hn Aleksander Hartvedt Olsen Myklebust ◽  
Stefan Andersson ◽  
Gabriella Tranell
Keyword(s):  
Oxygen Content ◽  
Flow Rate ◽  
Gas Flow ◽  
Formation Rate ◽  
Bulk Composition ◽  
High Rate ◽  
Ferroalloy Production ◽  
Operational Parameters ◽  
High Carbon ◽  
High Carbon Ferromanganese

AbstractThermal fume formation is a problem in manganese ferroalloy production and the metal production industry at large. A better understanding of the mechanisms of fume formation and the operational parameters affecting the fume formation rate may help in reducing and managing fuming. This paper aims to investigate the effects of oxygen content and gas flow rate on the fuming rate and fume particulate properties for liquid high-carbon ferromanganese. The fuming rates were attained experimentally by measuring the fume flux with respect to oxygen content and gas velocity above the metal melt. The generated fumes were also characterized in terms of particle size and element distribution between fume and melt. The fuming rates were found to steadily increase with increasing oxygen content and flow rate of the gas up to a point where the curve flattens, following theoretical predictions. However, the highest flux values measured were above the theoretical limitations of the evaporation flux in vacuo given the alloy bulk composition. It is hypothesized that the high rate of fuming is caused by an increased manganese activity at the alloy surface due to local decarburization of the alloy in contact with the oxidizing gas. Graphical Abstract

Characterizations and Process Parameters of Titanium Dioxide Thin Film by RF Sputtering

2013 ◽  
Vol 22 ◽  
pp. 9-21 ◽  
Author(s):  
Chii Rong Yang ◽  
Tun Ping Teng ◽  
Yun Yu Yeh
Keyword(s):  
Thin Films ◽  
Oxygen Content ◽  
Flow Rate ◽  
Gas Flow ◽  
Deposition Time ◽  
Photocatalytic Performance ◽  
Oxidation Process ◽  
Rf Sputtering ◽  
Rf Magnetron Sputtering ◽  
Oxygen Ratio

In this study, we successfully combined RF magnetron sputtering of a pure Ti metal target and one-stage oxidation process with a wider oxygen ratio (10%-90%) and total sputtering flow rate (16-24 sccm) to produce TiO2thin films on a glass substrate. The crystallization, morphology, roughness, and thickness of the thin films were examined using XRD, HR-FESEM, AFM, and a profilometer. Subsequently, the photocatalytic performance was examined using a spectrometer and video tensiometer. The experimental results show that the TiO2thin films with a majority of anatase and higher roughness exhibit superior photocatalytic performance; the total sputtering gas flow rate of 18 sccm and oxygen content at 10% is the optimal option. Finally, an empirical formula to correlate the film thickness with deposition time was conducted for the sputtering flow rate of 18 sccm and the oxygen content of 10%.

scholarly journals Influence of Submerged Entry Nozzle Port Blockage on the Meniscus Fluctuation Considering Various Operational Parameters

Metals ◽  
2020 ◽  
Vol 10 (2) ◽  
pp. 269 ◽  
Author(s):  
Manish Kumar ◽  
Praveen Mishra ◽  
Apurba Kumar Roy
Keyword(s):  
Flow Rate ◽  
Gas Flow ◽  
Wave Amplitude ◽  
Water Flow Rate ◽  
Submerged Entry Nozzle ◽  
Casting Process ◽  
Water Model ◽  
Maximum Height ◽  
Operational Parameters ◽  
The Right

The continuous casting process (CCP) is the most vital part of steelmaking. The flow pattern near the submerged entry nozzle (SEN) and mould greatly influence the quality of the slab produced. The present investigation was carried out to gain knowledge regarding the meniscus fluctuation under different nozzle port blockage conditions by water model experiments. The experiments were carried out to study the effect of no blockage, 25% blockage, 50% blockage, and 75% blockage of the nozzle port on mould-level fluctuations. The result shows that when the liquid flow rate increases, the wave amplitude increases. In these experiments, the average and maximum meniscus fluctuations were measured while changing different variables such as the water flow rate, gas flow rate, and one-side percentage blockage of the SEN port while the other side was fully open. The observation shows that when the port size decreases, the fluid steel mixed from the obstructing side to the open side results in asymmetry. The average and maximum wave amplitude increases with decreasing submergence depth. It was observed that the maximum height of the standing waves in the mould continued rising on the non-blocked side of the SEN. Blockage increases from 25% to 75%, and with 75% blockage of the right side of the SEN port, the mould-level fluctuation at the left side of the mould was extreme, while that of the right side was relatively quiet.

Effect of Gas Flow Rate on the High-Rate, Localized Jet-Deposition of Silicon in SiH4/H2 PE-CVD

2014 ◽  
Vol 47 (6) ◽  
pp. 478-482 ◽  
Author(s):  
Satoshi Nishida ◽  
Hiroshi Muta ◽  
Shizuma Kuribayashi
Keyword(s):  
Flow Rate ◽  
Gas Flow ◽  
High Rate ◽  
Gas Flow Rate

Influence of the total gas flow rate on high rate growth microcrystalline silicon films and solar cells

2009 ◽  
Vol 18 (8) ◽  
pp. 3563-3567 ◽  
Author(s):  
Han Xiao-Yan ◽  
Hou Guo-Fu ◽  
Zhang Xiao-Dan ◽  
Wei Chang-Chun ◽  
Li Gui-Jun ◽  
...  
Keyword(s):  
Solar Cells ◽  
Flow Rate ◽  
Gas Flow ◽  
Silicon Films ◽  
High Rate ◽  
Gas Flow Rate ◽  
Microcrystalline Silicon

A Novel Electrode for the Degradation of Methylene Blue in Electrochemical System: Preparation and Characterization

2010 ◽  
Vol 113-116 ◽  
pp. 1407-1410 ◽  
Author(s):  
Qi Zhou Dai ◽  
Fei Liao ◽  
Shao Qing Cai ◽  
Jia De Wang ◽  
Jian Meng Chen
Keyword(s):  
Hydrogen Peroxide ◽  
Flow Rate ◽  
Gas Flow ◽  
Dye Removal ◽  
Dye Wastewater ◽  
Mass Ratio ◽  
Operational Parameters ◽  
Cathodic Potential ◽  
Active Electrode ◽  
Wastewater Pollution

Organic wastewater pollution control was one of the focus researches for environmental workers. In this study, high active electrode was made and hydrogen peroxide production via cathodic reduction of oxygen was studied, the H2O2 generated in the optimization of research and the effect of dye wastewater degradation under the typical conditions were explored. The effects of mass ratio between graphite and PTFE, Na2SO4 concentration, cathodic potential, pH and gas flow rate on hydrogen peroxide output were investigated. The optimized operational parameters were as follows: graphite and PTFE 5:1, pH=6, Na2SO4 concentration 0.5 mol/L, oxygen flow rate 450mL/min, and cathodic potential -1.2 V (vs SCE). Hydrogen peroxide concentration could reach 66.17 mg/L after 2h at optimized condition. Meanwhile, dye removal could reach about 70% at the same time. Therefore, the use of active electrode as cathode has shown promising prospect in dye wastewater treatment.

Dynamic Model Simulation and Verification of a Two-Stage High-Rate Anaerobic Treatment Process with Recycle

1993 ◽  
Vol 28 (11-12) ◽  
pp. 197-207 ◽  
Author(s):  
J. Keller ◽  
M. Romli ◽  
P. L. Lee ◽  
P. F. Greenfield
Keyword(s):  
Sodium Hydroxide ◽  
Flow Rate ◽  
Gas Flow ◽  
Model Simulation ◽  
Anaerobic Treatment ◽  
High Rate ◽  
Continuous Reactor ◽  
Feed Concentration ◽  
Two Phase ◽  
Significant Discrepancy

The effect of overload on a two-phase high rate anaerobic wastewater treatment system with recycle was determined experimentally and simulated dynamically using a structured model. The experimental system consisted of a well mixed continuous reactor, controlled at pH 6 by sodium hydroxide addition, as the acidification stage and a fluidized bed reactor for the methanogenic stage, with an additional recycle connection from the second to the first reactor. Step changes in the feed concentration as well as in the feed flow rate were investigated and compared to simulation predictions. Operation without recycle was modelled accurately, with the simulation data of most process variables matching the experimental results quantitatively. The application of the same model to recycle operation showed significant discrepancy between the experimental and simulated data for the sodium hydroxide consumption rate and the gas flow rate in the acidification reactor. Although the actual values were different, the qualitative responses of the experimental and simulated step changes were similar. Other simulated variables showed good agreement with the experimental measurements. The model provides a useful tool for design and control studies in systems without recycle and, with some modification, for operation with recycle.

SCIENTIFIC AND ENGINEERING PRINCIPLES OF EFFICIENT FUEL USE AND ENVIRONMENTALLY FRIENDLY GAS COMBUSTION IN STOVE PLATES. PART 1. MODERN STATE-OF-THE-ART AND DIRECTIONS FOR IMPROVEMENT THE GAS BURNING IN DOMESTIC GAS COOKERS

2017 ◽  
pp. 3-18 ◽  
Author(s):  
B.S. Soroka ◽  
V.V. Horupa
Keyword(s):  
Natural Gas ◽  
Flow Rate ◽  
Gas Flow ◽  
Renewable Energy Sources ◽  
Combustion Process ◽  
Orifice Diameter ◽  
Firing Process ◽  
Gas Flow Rate ◽  
Gas Combustion ◽  
Gas Stoves

Natural gas NG consumption in industry and energy of Ukraine, in recent years falls down as a result of the crisis in the country’s economy, to a certain extent due to the introduction of renewable energy sources along with alternative technologies, while in the utility sector the consumption of fuel gas flow rate enhancing because of an increase the number of consumers. The natural gas is mostly using by domestic purpose for heating of premises and for cooking. These items of the gas utilization in Ukraine are already exceeding the NG consumption in industry. Cooking is proceeding directly in the living quarters, those usually do not meet the requirements of the Ukrainian norms DBN for the ventilation procedures. NG use in household gas stoves is of great importance from the standpoint of controlling the emissions of harmful components of combustion products along with maintenance the satisfactory energy efficiency characteristics of NG using. The main environment pollutants when burning the natural gas in gas stoves are including the nitrogen oxides NOx (to a greater extent — highly toxic NO2 component), carbon oxide CO, formaldehyde CH2O as well as hydrocarbons (unburned UHC and polyaromatic PAH). An overview of environmental documents to control CO and NOx emissions in comparison with the proper norms by USA, EU, Russian Federation, Australia and China, has been completed. The modern designs of the burners for gas stoves are considered along with defining the main characteristics: heat power, the natural gas flow rate, diameter of gas orifice, diameter and spacing the firing openings and other parameters. The modern physical and chemical principles of gas combustion by means of atmospheric ejection burners of gas cookers have been analyzed from the standpoints of combustion process stabilization and of ensuring the stability of flares. Among the factors of the firing process destabilization within the framework of analysis above mentioned, the following forms of unstable combustion/flame unstabilities have been considered: flashback, blow out or flame lifting, and the appearance of flame yellow tips. Bibl. 37, Fig. 11, Tab. 7.

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