scholarly journals Optimisation of Operational Parameters of a Spiral Classifier Using Design of Experiment (DOE)

2020 ◽  
Vol 20 (1) ◽  
pp. 45-50
Author(s):  
K. Ackah ◽  
C. Owusu ◽  
F. Amoah
Keyword(s):  
Design Of Experiment ◽  
Great Influence ◽  
Confirmatory Test ◽  
Operational Parameters ◽  
Operational Conditions ◽  
Operating Process ◽  
Manganese Concentrate ◽  
Concentrate Grade ◽  
Spiral Classifier ◽  
System Operating

Abstract Classifying Mn Ore to improve upon the grade and the properties has become a crucial activity for the Mn industry since it increases the market value of the ore. Ghana Manganese Company (GMC) has renovated their oxide washing plant by integrating it with a spiral classifier to make a batch system operating process. Particle size of <3.35mm (Mn grade of 43-47%) obtained from the primary section of the plant served as feed to the classifier and with the plant condition (i.e. at 60 min washing time, 30 rev/min speed of spirals and feed tonnage of 6 t), Mn grade of 49% was achieved. This paper focused on the optimisation of some selected operational parameters of the classifier to obtain a Mn grade >50% using Design of Experiment (DOE). Series of test works were designed using the DOE for the classifier using the constraints of washing time (30-90 min), speed of spirals (20-40 rev/min) and feed tonnage (6-9 t). The outcome of the test work after simulation showed that all the selected parameters had a great influence on Mn grade. The spiral speed and feed tonnage correlated negatively to the Mn grade with washing time correlating positively. Operating the spiral classifier at a feed rate, spiral speed and washing time of 6 t, 25 rev/min, and 30 min, respectively, yielded Mn grade of 53%. A Confirmatory test using the established conditions gave a Mn grade of 53%, which is a 4% increment in the previous Mn grade which was 47%. The outcome of the studies is the new established operational conditions which is adhered to by the plant, producing a manganese concentrate grade ranging between 52-54%.   Keywords: Design of Experiment (DOE), Spiral Classifier, Grade, Manganese

scholarly journals Hydrogen Production by Fluidized Bed Reactors: A Quantitative Perspective Using the Supervised Machine Learning Approach

J ◽  
2021 ◽  
Vol 4 (3) ◽  
pp. 266-287
Author(s):  
Zheng Lian ◽  
Yixiao Wang ◽  
Xiyue Zhang ◽  
Abubakar Yusuf ◽  
Lord Famiyeh ◽  
...  
Keyword(s):  
Machine Learning ◽  
Hydrogen Production ◽  
Fluidized Bed ◽  
Biomass Gasification ◽  
Supervised Machine Learning ◽  
Fluidized Bed Reactors ◽  
Hydrogen Yield ◽  
Carbon Conversion ◽  
Operational Parameters ◽  
Operational Conditions

The current hydrogen generation technologies, especially biomass gasification using fluidized bed reactors (FBRs), were rigorously reviewed. There are involute operational parameters in a fluidized bed gasifier that determine the anticipated outcomes for hydrogen production purposes. However, limited reviews are present that link these parametric conditions with the corresponding performances based on experimental data collection. Using the constructed artificial neural networks (ANNs) as the supervised machine learning algorithm for data training, the operational parameters from 52 literature reports were utilized to perform both the qualitative and quantitative assessments of the performance, such as the hydrogen yield (HY), hydrogen content (HC) and carbon conversion efficiency (CCE). Seven types of operational parameters, including the steam-to-biomass ratio (SBR), equivalent ratio (ER), temperature, particle size of the feedstock, residence time, lower heating value (LHV) and carbon content (CC), were closely investigated. Six binary parameters have been identified to be statistically significant to the performance parameters (hydrogen yield (HY)), hydrogen content (HC) and carbon conversion efficiency (CCE)) by analysis of variance (ANOVA). The optimal operational conditions derived from the machine leaning were recommended according to the needs of the outcomes. This review may provide helpful insights for researchers to comprehensively consider the operational conditions in order to achieve high hydrogen production using fluidized bed reactors during biomass gasification.

Enhanced photocatalytic activity of CeO2 using β-cyclodextrin on visible light assisted decoloration of methylene blue

2013 ◽  
Vol 69 (1) ◽  
pp. 113-119 ◽  
Author(s):  
Sakthivel Pitchaimuthu ◽  
Ponnusamy Velusamy
Keyword(s):  
Methylene Blue ◽  
Photocatalytic Activity ◽  
Visible Light ◽  
Inclusion Complexation ◽  
Processing Parameters ◽  
Operational Parameters ◽  
Illumination Time ◽  
Operational Conditions ◽  
Electron Microscopy Analysis ◽  
Initial Ph

An attempt has been made to enhance the photocatalytic activity of CeO2 for visible light assisted decoloration of methylene blue (MB) dye in aqueous solutions by β-cyclodextrin (β-CD). The inclusion complexation patterns between host and guest (i.e., β-CD and MB) have been confirmed with UV–visible spectral data. The interaction between CeO2 and β-CD has also been characterized by field emission scanning electron microscopy analysis. The photocatalytic activity of the catalyst under visible light was investigated by measuring the photodegradation of MB in aqueous solution. The effects of key operational parameters such as initial dye concentration, initial pH, CeO2 concentration as well as illumination time on the decolorization extents were investigated. Among the processing parameters, the pH of the reaction solution played an important role in tuning the photocatalytic activity of CeO2. The maximum photodecoloration rate was achieved at basic pH (pH 11). Under the optimum operational conditions, approximately 99.6% dye removal was achieved within 120 min. The observed results indicate that the decolorization of the MB followed a pseudo-first order kinetics.

Surveillance Models of Large-Scale ESP With High Viscosity Fluids and Gas

2012 ◽  
Author(s):  
Lissett Barrios ◽  
Stuart Scott ◽  
Charles Deuel
Keyword(s):  
Large Scale ◽  
Two Phase Flow ◽  
Electrical Current ◽  
High Viscosity ◽  
Viscous Fluids ◽  
Phase Flow ◽  
Centrifugal Pumps ◽  
Operational Parameters ◽  
Two Phase ◽  
Operational Conditions

The paper reports on developmental research on the effects of viscosity and two phases, liquid–gas fluids on ESPs which are multi stage centrifugal pumps for deep bore holes. Multiphase viscous performance in a full-scale Electrical Submersible Pump (ESP) system at Shell’s Gasmer facility has been studied experimentally and theoretically. The main objectives is to predict the operational conditions that cause degradations for high viscosity fluids when operating in high Gas Liquid Radio (GLR) wells to support operation in Shell major Projects. The system studied was a 1025 series tandem WJE 1000. The test was performed using this configuration with ten or more pump stages moving fluids with viscosity from 2 to 200 cP at various speed, intake pressure and Gas Void Fractions (GVF). For safety considerations the injected gas was restricted to nitrogen or air. The ESP system is a central artificial lift method commonly used for medium to high flow rate wells. Multiphase flow and viscous fluids causes problems in pump applications. Viscous fluids and free gas inside an ESP can cause head degradation and gas locking. Substantial attempts have been made to model centrifugal pump performance under gas-liquid viscous applications, however due to the complexity this is still a uncertain problem. The determination of the two-phase flow performance in these harmful conditions in the ESP is fundamental aspects in the surveillance operation. The testing at Shell’s Gasmer facility revealed that the ESP system performed as theoretical over the range of single flowrates and light viscosity oils up to Gas Volume Fractions (GVF) around 25%. The developed correlations predict GVF at the pump intake based on the operational parameters. ESP performance degrades at viscosity higher than 100cp as compared to light oil applications, gas lock condition is observed at gas fraction higher than 45%. Pump flowrate can be obtained from electrical current and boost for all range of GVF and speed. The main technical contributions are the analysis of pump head degradation under two important variables, high viscosity and two-phase flow inside the ESP.

scholarly journals Evaluation of the SteamVR Motion Tracking System with a Custom-Made Tracker

2021 ◽  
Vol 11 (14) ◽  
pp. 6390
Author(s):  
Marcin Maciejewski
Keyword(s):  
Motion Tracking ◽  
Tracking System ◽  
Training System ◽  
Random Errors ◽  
Operational Conditions ◽  
Custom Made ◽  
Systematic And Random Errors ◽  
Position And Orientation ◽  
Motion Tracking System ◽  
System Operating

The paper presents the research of the SteamVR tracker developed for a man-portable air-defence training system. The tests were carried out in laboratory conditions, with the tracker placed on the launcher model along with elements ensuring the faithful reproduction of operational conditions. During the measurements, the static tracker was moved and rotated in a working area. The range of translations and rotations corresponded to the typical requirements of a shooting simulator application. The results containing the registered position and orientation values were plotted on 3D charts which showed the tracker’s operation. Further analyses determined the values of the systematic and random errors for measurements of the SteamVR system operating with a custom-made tracker. The obtained results with random errors of 0.15 mm and 0.008° for position and orientation, respectively, proved the high precision of the measurements.

scholarly journals Niche Differentiation among Three Closely RelatedCompetibacteraceaeClades at a Full-Scale Activated Sludge Wastewater Treatment Plant and Putative Linkages to Process Performance

2018 ◽  
Vol 85 (5) ◽  
Author(s):  
Veronica R. Brand ◽  
Laurel D. Crosby ◽  
Craig S. Criddle
Keyword(s):  
Wastewater Treatment ◽  
Activated Sludge ◽  
Wastewater Treatment Plant ◽  
Treatment Plant ◽  
Niche Differentiation ◽  
Full Scale ◽  
Pure Oxygen ◽  
Operational Parameters ◽  
Metabolic Potential ◽  
Operational Conditions

ABSTRACTMultiple clades within a microbial taxon often coexist within natural and engineered environments. Because closely related clades have similar metabolic potential, it is unclear how diversity is sustained and what factors drive niche differentiation. In this study, we retrieved three near-complete Competibacter lineage genomes from activated sludge metagenomes at a full-scale pure oxygen activated sludge wastewater treatment plant. The three genomes represent unique taxa within theCompetibacteraceae. A comparison of the genomes revealed differences in capacity for exopolysaccharide (EPS) biosynthesis, glucose fermentation to lactate, and motility. Using quantitative PCR (qPCR), we monitored these clades over a 2-year period. The clade possessing genes for motility and lacking genes for EPS biosynthesis (CPB_P15) was dominant during periods of suspended solids in the effluent. Further analysis of operational parameters indicate that the dominance of the CPB_P15 clade is associated with low-return activated sludge recycle rates and low wasting rates, conditions that maintain relatively high levels of biomass within the system.IMPORTANCEMembers of the Competibacter lineage are relevant in biotechnology as glycogen-accumulating organisms (GAOs). Here, we document the presence of threeCompetibacteraceaeclades in a full-scale activated sludge wastewater treatment plant and their linkage to specific operational conditions. We find evidence for niche differentiation among the three clades with temporal variability in clade dominance that correlates with operational changes at the treatment plant. Specifically, we observe episodic dominance of a likely motile clade during periods of elevated effluent turbidity, as well as episodic dominance of closely related nonmotile clades that likely enhance floc formation during periods of low effluent turbidity.

Well Control Simulation With Nonaqueous Drilling Fluids

2020 ◽  
Vol 143 (3) ◽  
Author(s):  
Felipe Chagas ◽  
Paulo R. Ribeiro ◽  
Otto L. A. Santos
Keyword(s):  
Drilling Fluid ◽  
Petroleum Industry ◽  
Critical Issue ◽  
Drilling Fluids ◽  
Operational Parameters ◽  
Data Set ◽  
Well Control ◽  
Operational Conditions ◽  
Control Research ◽  
Drilling Operations

Abstract The demand for energy has increased recently worldwide, requiring new oilfield discoveries to supply this need. Following this demand increase, challenges grow in all areas of the petroleum industry especially those related to drilling operations. Due to hard operational conditions found when drilling complex scenarios such as high-pressure/high-temperature (HPHT) zones, deep and ultradeep water, and other challenges, the use nonaqueous drilling fluids became a must. The reason for that is because this kind of drilling fluid is capable to tolerate these extreme drilling conditions found in those scenarios. However, it can experience changes in its properties as a result of pressure and temperature variations, requiring special attention during some drilling operations, such as the well control. The well control is a critical issue since it involves safety, social, economic, and environmental aspects. Well control simulators are a valuable tool to support well control operations and preserve the well integrity, verifying operational parameters and to assist drilling engineers in the decision-making process during well control operations and kick situations. They are also important computational tools for rig personnel training. This study presents well control research and development contributions, as well as the results of a computational well control simulator that applies the Driller's method and allows the understanding the thermodynamic behavior of synthetic drilling fluids, such as n-paraffin and ester base fluids. The simulator employed mathematical correlations for the drilling fluids pressure–volume–temperature (PVT) properties obtained from the experimental data. The simulator results were compared to a test well data set as well to the published results from other kick simulators.

Modelling of Power Transmission Systems for Design Optimization and Diagnostics of Gear in Operational Conditions

2013 ◽  
Vol 210 ◽  
pp. 108-114
Author(s):  
Grzegorz Peruń ◽  
Bogusław Łazarz
Keyword(s):  
Dynamic Model ◽  
Power Transmission ◽  
Test Stand ◽  
Laser Vibrometer ◽  
Operational Parameters ◽  
Operational Conditions ◽  
Power Transmission Systems ◽  
Laboratory Examinations ◽  
Transversal Vibrations ◽  
Dynamic Phenomena

This article presents the author's dynamic model of power circulating gear test stand. It was assumed, that properly defined and next identified model can be used to analyze dynamic phenomena in meshing and bearings of gears and allows optimizing their construction, especially to minimize their vibroactivity. The article includes description of the construction of a test-stand, as well as short characteristic of the dynamic model. Afterwards it was presented verification, whether the model was correctly fine tuned. For verification purpose, were conducted laboratory measurements of velocity of transversal vibrations at the test-stand using laser vibrometer. Results of laboratory examinations were compared with the results achieved during computer simulation. Developed and presented dynamic model take into account a number of design, technological and operational parameters of gear. It was also presented algorithm of researches aimed at minimizing the vibroactivity of gear.

SI and HCCI Combustion Mode Transition Control of a Multi-Cylinder HCCI Capable SI Engine via Iterative Learning

2011 ◽  
Author(s):  
Xiaojian Yang ◽  
Guoming G. Zhu
Keyword(s):  
Control Strategy ◽  
Iterative Learning ◽  
Mode Transition ◽  
Combustion Mode ◽  
Operational Parameters ◽  
Ic Engine ◽  
Operational Conditions ◽  
Transition Control ◽  
Hcci Combustion ◽  
Mode Transition Control

The combustion mode transition between spark ignition (SI) and homogeneously charged compression ignition (HCCI) combustions of an internal combustion (IC) engine is challenging due to the distinct engine operational parameters over these two combustion modes and the cycle-to-cycle residue gas dynamics of the HCCI combustion. The control problem becomes even more complicated when multi-cylinder operation is involved. This paper studies the combustion mode transition problem of a multi-cylinder IC engine with dual-stage valve lifts and electrical variable valve timing systems. A control oriented engine model was used to develop a multistep mode transition control strategy via iterative learning for combustion mode transition between SI to HCCI with minimal engine torque fluctuations. The hardware-in-the-loop (HIL) simulations demonstrated the effectiveness of the developed control strategy for the combustion mode transition under both constant load and transient engine operational conditions.

The Stability of the Self-Lubricated Journal Slider Bearing

2014 ◽  
Author(s):  
Valentin Stingelin
Keyword(s):  
Entire Range ◽  
The Self ◽  
Stable Operation ◽  
Slider Bearing ◽  
Operational Parameters ◽  
Dimensionless Numbers ◽  
Operational Conditions ◽  
Reaction Forces ◽  
The Stability

Un-equivocal criteria could be established assuring a perfectly stable operation of the shaft in a restricted, but nevertheless technically interesting range of operational conditions. It enables bearing designers to choose all physical and operational parameters in order to avoid the so called “half speed whirl”. This study hopes to bring enough new elements to attenuate the ill merited reputation of such bearings. Therefore the relevant dimensionless numbers were identified and quantified. What was done for an L/D=1, can be applied to any other bearing configuration, provided the quasi-steady reaction forces, acting on the shaft, are known for the entire range of eccentricities 0<ε<0.9.

scholarly journals DETERMINAÇÃO DAS MELHORES CONDIÇÕES OPERACIONAIS DO PROCESSO DE PRODUÇÃO DA RICOTA

2005 ◽  
Vol 23 (1) ◽  
Author(s):  
LIA DE MENDONÇA PORTO ◽  
RINALDO CARDOSO DOS SANTOS ◽  
TÂNIA LÚCIA SANTOS MIRANDA
Keyword(s):  
Chemical Oxygen Demand ◽  
Sensory Evaluation ◽  
Cheese Whey ◽  
Great Influence ◽  
Skim Milk ◽  
Oxygen Demand ◽  
Value Addition ◽  
Operational Conditions ◽  
Before And After

Neste trabalho foram analisadas as melhores condições operacionais de produção de ricota, visando avaliar a agregação de valor desse processo ao soro do queijo e diminuição de seu potencial poluente. Desenvolveu-se planejamento fatorial 23, considerando as seguintes variáveis: tempo de precipitação, temperatura e pH nos quais seria possível a obtenção das ricotas produzidas com soro puro e com adição de leite e leite em pó desnatado ao soro. Os resultados foram analisados em relação à recuperação de proteína existente na mistura inicial (soro+leite), aos teores de lactose e gordura nos soros e a demanda química de oxigênio (DQO) do soro antes e depois da produção para analisar seu efeito poluidor. Obteve-se melhor condição de produção em pH 5,0 e temperatura de 92ºC. O tempo de precipitação não apresentou grande influência no processo e a DQO mostrou-se dependente do teor de lactose do soro. Efetuou-se avaliação da viabilidade econômica do processo com e sem a adição de leite, bem como avaliação sensorial das ricotas economicamente viáveis. Não houve diferença na aceitação entre as ricotas. O leite deve ser adicionado em pequenas quantidades, ainda que com elevação de custo para melhorar as condições de coleta da massa da ricota no processo. DETERMINATION OF THE BEST OPERATIONAL CONDITIONS FOR THE RICOTTA PRODUCING PROCESS Abstract The best of operational conditions for the ricotta producing process were analyzed in this work, aiming to evaluate the value addition of this process to cheese whey and reducing its pollutant potential. A factorial 23 scheme was developed considering the following variables: time of precipitation, temperature and pH in which ricotta obtention was possible when prepared from pure whey and with the addition of milk or powdered skim-milk. Results were analysed in relation to the recovery of protein existing in the initial blend (whey+milk), to lactose and fat content of the wheys and to the chemical oxygen demand (COD) of the wheys before and after the production in order to analyze the pollutant effect. The best operational conditions were obtained at pH 5.0 and 92ºC. Time of precipitation did not show great influence in the process and COD was shown as being dependent on the lactose content of the whey. Evaluation of the economical viability of the process was also performed with and without milk addition, as well as a sensory evaluation of the economically viable ricottas. There was no difference in acceptation among the ricottas. Although milk must be added to whey in small amounts, even with cost increase, in order to improve the ricotta mass recovery conditions in the process.

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