Froth Flotation Beneficiation a Sure Way to Value Addition to Arufu (Nigeria) Zinc Ore Towards Smelting Grade Concentrate Production

Froth flotation of Arufu ore was carried out at varying particle sizes after characterization. Fifty (50) kilogram crude sample of the ore was sourced from Arufu zinc mine in Arufu town of Nassarawa state, Nigeria. The whole sample was crushed out of which five (5) kilogram was sampled out using random sampling method. One kilogram each of the resulting sample was then ground and sieved to three particle sizes viz; 63 µm, 90 µm and 125 µm. Chemical analysis of the representative sample of the sourced ore was carried out using Energy Dispersive X-Ray Fluorescence Spectrometer (ED –XRF). 250 grams of the 63 µm sample was charged into Froth flotation cell mixed with water at a ratio of 1:4 to form slurry. The Slurry formed was condition to a pH of 9, while other froth flotation reagents were added one after the other. This resulted in froth and depressed samples, which were dewatered after 24 hours and samples picked for compositional analysis. The procedure was repeated for 90 µm and 125 µm. The characterization of head sample revealed that the ore contains predominantly 36.80%ZnO (26.29% Zn), 31.1 % SiO2 alongside other trace mineral as gangue in the ore. However, Froth flotation studies of the ore at varying particle size revealed that, appreciable amount of mineral of interest (ZnO) was lost to the tailing at sieve sizes 63 µm and 90 µm. This was attributed to over-grinding above the ore’s liberation size phenomenon which has been proven to have adverse effect on the mineral’s quality and overall separation efficiency. It was concluded that the froth flotation is best carried out at a particle size of 125 µm, pH of 9, using potassium ethyl xanthate (PEX) as frother to yield concentrate grade of 50.21 % ZnO (35.93 % Zn) at a recovery of 46.3%. This was re – cleaned to yield high grade of 82.36%ZnO (66.42%Zn). The re – cleaned concentrate produced falls within the standard requirement of 65 % Zn needed as a charge into the blast furnace for Zinc metal production.

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A Review of Flotation Separation of Mg Carbonates (Dolomite and Magnesite)

Minerals ◽

10.3390/min8080354 ◽

2018 ◽

Vol 8 (8) ◽

pp. 354 ◽

Cited By ~ 13

Author(s):

Darius Wonyen ◽

Varney Kromah ◽

Borbor Gibson ◽

Solomon Nah ◽

Saeed Chelgani

Keyword(s):

Particle Size ◽

Adverse Effects ◽

Zeta Potential ◽

Separation Efficiency ◽

Froth Flotation ◽

Surface Characteristics ◽

Economic Viability ◽

Ore Bodies

It is well documented that flotation has high economic viability for the beneficiation of valuable minerals when their main ore bodies contain magnesium (Mg) carbonates such as dolomite and magnesite. Flotation separation of Mg carbonates from their associated valuable minerals (AVMs) presents several challenges, and Mg carbonates have high levels of adverse effects on separation efficiency. These complexities can be attributed to various reasons: Mg carbonates are naturally hydrophilic, soluble, and exhibit similar surface characteristics as their AVMs. This study presents a compilation of various parameters, including zeta potential, pH, particle size, reagents (collectors, depressant, and modifiers), and bio-flotation, which were examined in several investigations into separating Mg carbonates from their AVMs by froth flotation.

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Flotation study on low-grade antimony ore of qilla abdullah, Balochistan, Pakistan

Bangladesh Journal of Scientific and Industrial Research ◽

10.3329/bjsir.v49i2.22003 ◽

2015 ◽

Vol 49 (2) ◽

pp. 95-102

Author(s):

MA Bhatti ◽

KR Kazmi ◽

A Mehmood ◽

R Mehmood ◽

A Ahad ◽

...

Keyword(s):

Particle Size ◽

Froth Flotation ◽

Agitation Speed ◽

Pulp Density ◽

Low Grade ◽

Single Factor ◽

Flotation Technique ◽

Concentrate Grade ◽

Optimum Grade

A low-gradeantimony deposit originating from district Qilla Abdullah, Balochistan Province of Pakistan, containing stibnite as an economical mineral was beneficiated by froth flotation technique. Flotation parameters such as particle size of the feed, pulp density, pH of the pulp, agitation speed, type and dose of reagents (i.e. collector, frother, activator, regulator and modifier) and the conditioning time were studied on the basis of single-factor variation experiment in order to get the optimum grade and recovery. Regrinding of the rougher concentrate followed by cleaning andrecleaning of rougher concentrateensured a final concentrate grade of 65.12% Sb@ 85.79% recovery. This concentrate is suitable for the extraction of metal and production of chemicals. DOI: http://dx.doi.org/10.3329/bjsir.v49i2.22003 Bangladesh J. Sci. Ind. Res. 49(2), 95-102, 2014

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Separation characteristics in dissolved air flotation - pilot and full-scale demonstration

Water Science & Technology ◽

10.2166/wst.2003.0169 ◽

2003 ◽

Vol 48 (3) ◽

pp. 89-96

Author(s):

M. Ljunggren ◽

L. Jönsson

Keyword(s):

Particle Size ◽

Contact Zone ◽

Separation Efficiency ◽

Particle Separation ◽

Full Scale ◽

Particle Sizes ◽

Dissolved Air Flotation ◽

Air Flotation ◽

Practical Implications ◽

Dissolved Air

This study presents practical implications for particle separation in Dissolved Air Flotation (DAF). The objectives were to localise where particles are separated from the water phase and to determine what particles, in terms of size, are removed by the DAF-process. Both pilot- and full-scale plants were investigated. Particle sizes were analysed with a light-blocking particle counter and an optical borescope was used for visualisation of particle-bubble aggregates. It was found that particles are preferably separated upstream in the process, i.e. close to the contact zone. Furthermore, separation efficiency for particles increased with increasing particle size.

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Particle Size Effect of Oyster Shell on Mortar: Experimental Investigation and Modeling

Materials ◽

10.3390/ma14226813 ◽

2021 ◽

Vol 14 (22) ◽

pp. 6813

Author(s):

Yingdi Liao ◽

Hongyi Shi ◽

Shimin Zhang ◽

Bo Da ◽

Da Chen

Keyword(s):

Mechanical Properties ◽

Particle Size ◽

Compressive Strength ◽

Elastic Modulus ◽

Flexural Strength ◽

Particle Sizes ◽

River Sand ◽

Standard Requirement ◽

Slump Flow ◽

Curing Age

In order to solve the problem of lack of natural river sand, crushed waste oyster shells (WOS) were used to replace river sand. By replacing 20% river sand, WOS mortar with different particle sizes of WOS were made for the experiment. Through experimental observation, the initial slump and slump flow loss rate were studied. The effects of different particle sizes and curing times on the compressive strength, flexural strength, static elastic modulus, and dry shrinkage of WOS mortar were analyzed. The relationship formulas between the compressive strength, flexural strength, particle size, and curing age were proposed. The results showed that the setting time and slump flow decreased with a decrease in the particle size of WOS. It was also found that the mortar with fine crushed WOS had high compressive strength, flexural strength, and static elastic modulus at both early and long-term curing age. A formula was proposed to describe the development of the compressive strength with the particle size of WOS and curing time, and the relations among these mechanical properties were discussed. Furthermore, drying shrinkage increased when WOS was used and could not satisfy the standard requirement of 0.075%. In contrast, the addition of fine WOS and double-dose sulfonated naphthalene-formaldehyde superplasticizer (SNF SP) reduced the shrinkage rate of the mortar by 8.35% and provided better workability and mechanical properties for mortar.

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Compositions and Particle Sizes of (RE)Ba2Cu3O7-X Superconductor Powders Synthesized by the Solution Combustion Technique

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.488-489.286 ◽

2012 ◽

Vol 488-489 ◽

pp. 286-290 ◽

Cited By ~ 2

Author(s):

Oratai Jongprateep ◽

Pimsiri Tangbuppa ◽

Nattawan Manasnilobon

Keyword(s):

Particle Size ◽

Average Particle Size ◽

Compositional Analysis ◽

Industrial Applications ◽

Average Particle ◽

Particle Sizes ◽

X Ray Diffraction ◽

Solution Combustion ◽

Superconducting Compounds ◽

Combustion Technique

Superconducting compounds (RE) Ba2Cu3O7-x (RE = rare earth such as Y, Er, Sm and Nd) can be exploited in various industrial applications such as cables, electric motors and energy storage systems. The project aimed at synthesizing fine-particle YBa2Cu3O7-x, ErBa2Cu3O7-x, SmBa2Cu3O7-x and NdBa2Cu3O7-x, powders with compositions suitable for the applications. Solution combustion technique was employed in the synthesis, using urea as fuel. Compositional analysis obtained from x-ray diffraction indicated that the as-synthesized powders contained the desired (RE)Ba2Cu3O7-x (RE123) superconducting phase and impurities, including (RE)2BaCuO5 (RE211), BaCO3 and Ba(NO3)2. However, majority of the impurities were eliminated when the powders were calcined at 900°C. Only (RE)Ba2Cu3O7-x (RE123) and (RE)2BaCuO5 (RE211) phases remained after calcination. Results from scanning electron microscope showed that the as-synthesized powders obtained from the solution combustion technique had relatively small particles with average particle size of 0.67 micrometers, while the calcined powders exhibited coarsening effects with average particle size of 4.4 micrometers.

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Fibrin Formation: The Role of the Fibrinogen-Fibrin Monomer Complex

Thrombosis and Haemostasis ◽

10.1055/s-0038-1648007 ◽

1976 ◽

Vol 36 (01) ◽

pp. 037-048 ◽

Cited By ~ 49

Author(s):

Eric P. Brass ◽

Walter B. Forman ◽

Robert V. Edwards ◽

Olgierd Lindan

Keyword(s):

Particle Size ◽

Induction Period ◽

Fibrin Clot ◽

Clot Formation ◽

Appreciable Amount ◽

Buffer System ◽

Homeostatic Mechanism ◽

Fibrin Formation ◽

Fibrin Monomer

SummaryThe process of fibrin formation using highly purified fibrinogen and thrombin was studied using laser fluctuation spectroscopy, a method that rapidly determines particle size in a solution. Two periods in fibrin clot formation were noted: an induction period during which no fibrin polymerization occurred and a period of rapid increase in particle size. Direct measurement of fibrin monomer polymerization and fibrinopeptide release showed no evidence of an induction period. These observations were best explained by a kinetic model for fibrin clot formation incorporating a reversible fibrinogen-fibrin monomer complex. In this model, the complex serves as a buffer system during the earliest phase of fibrin formation. This prevents the accumulation of free polymerizable fibrin monomer until an appreciable amount of fibrinogen has reacted with thrombin, at which point the fibrin monomer level rises rapidly and polymerization proceeds. Clinically, the complex may be a homeostatic mechanism preventing pathological clotting during periods of elevated fibrinogen.

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Surface energy of cellulosic materials: The effect of particle morphology, particle size, and hydroxyl number

TAPPI Journal ◽

10.32964/tj14.9.565 ◽

2015 ◽

Vol 14 (9) ◽

pp. 565-576 ◽

Cited By ~ 1

Author(s):

YUCHENG PENG ◽

DOUGLAS J. GARDNER

Keyword(s):

Particle Size ◽

Surface Energy ◽

Particle Morphology ◽

Nanofibrillated Cellulose ◽

Particle Sizes ◽

Hydroxyl Number ◽

Small Individual ◽

Dispersion Component ◽

Commercial Applications ◽

Lower Temperature

Understanding the surface properties of cellulose materials is important for proper commercial applications. The effect of particle size, particle morphology, and hydroxyl number on the surface energy of three microcrystalline cellulose (MCC) preparations and one nanofibrillated cellulose (NFC) preparation were investigated using inverse gas chromatography at column temperatures ranging from 30ºC to 60ºC. The mean particle sizes for the three MCC samples and the NFC sample were 120.1, 62.3, 13.9, and 9.3 μm. The corresponding dispersion components of surface energy at 30°C were 55.7 ± 0.1, 59.7 ± 1.3, 71.7 ± 1.0, and 57.4 ± 0.3 mJ/m2. MCC samples are agglomerates of small individual cellulose particles. The different particle sizes and morphologies of the three MCC samples resulted in various hydroxyl numbers, which in turn affected their dispersion component of surface energy. Cellulose samples exhibiting a higher hydroxyl number have a higher dispersion component of surface energy. The dispersion component of surface energy of all the cellulose samples decreased linearly with increasing temperature. MCC samples with larger agglomerates had a lower temperature coefficient of dispersion component of surface energy.

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Effect of particle size on phytochemical composition and antioxidant properties of Sargassum cristaefolium ethanol extract

Scientific Reports ◽

10.1038/s41598-021-95769-y ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

E. S. Prasedya ◽

A. Frediansyah ◽

N. W. R. Martyasari ◽

B. K. Ilhami ◽

A. S. Abidin ◽

...

Keyword(s):

Antioxidant Activity ◽

Particle Size ◽

Antioxidant Activities ◽

Antioxidant Properties ◽

Ethanol Extract ◽

Total Phenolic ◽

Particle Sizes ◽

Epicatechin Gallate ◽

Particle Size Reduction ◽

Phytochemical Composition

AbstractSample particle size is an important parameter in the solid–liquid extraction system of natural products for obtaining their bioactive compounds. This study evaluates the effect of sample particle size on the phytochemical composition and antioxidant activity of brown macroalgae Sargassum cristaefolium. The crude ethanol extract was extracted from dried powders of S.cristeafolium with various particle sizes (> 4000 µm, > 250 µm, > 125 µm, > 45 µm, and < 45 µm). The ethanolic extracts of S.cristaefolium were analysed for Total Phenolic Content (TPC), Total Flavonoid Content (TFC), phenolic compound concentration and antioxidant activities. The extract yield and phytochemical composition were more abundant in smaller particle sizes. Furthermore, the TPC (14.19 ± 2.08 mg GAE/g extract to 43.27 ± 2.56 mg GAE/g extract) and TFC (9.6 ± 1.8 mg QE/g extract to 70.27 ± 3.59 mg QE/g extract) values also significantly increased as particle sizes decreased. In addition, phenolic compounds epicatechin (EC), epicatechin gallate (ECG), epigallocatechin (EGC), and Epigallocatechin gallate (EGCG) concentration were frequently increased in samples of smaller particle sizes based on two-way ANOVA and Tukey’s multiple comparison analysis. These results correlate with the significantly stronger antioxidant activity in samples with smaller particle sizes. The smallest particle size (< 45 µm) demonstrated the strongest antioxidant activity based on DPPH, ABTS, hydroxyl assay and FRAP. In addition, ramp function graph evaluates the desired particle size for maximum phytochemical composition and antioxidant activity is 44 µm. In conclusion, current results show the importance of particle size reduction of macroalgae samples to increase the effectivity of its biological activity.

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Experimental Analysis of the Mechanical Properties and Resistivity of Tectonic Coal Samples with Different Particle Sizes

Energies ◽

10.3390/en14082303 ◽

2021 ◽

Vol 14 (8) ◽

pp. 2303

Author(s):

Congyu Zhong ◽

Liwen Cao ◽

Jishi Geng ◽

Zhihao Jiang ◽

Shuai Zhang

Keyword(s):

Mechanical Properties ◽

Particle Size ◽

Compressive Strength ◽

Elastic Modulus ◽

Uniaxial Compressive Strength ◽

Coalbed Methane ◽

Coal Sample ◽

Fine Particles ◽

Particle Sizes ◽

Tectonic Coal

Because of its weak cementation and abundant pores and cracks, it is difficult to obtain suitable samples of tectonic coal to test its mechanical properties. Therefore, the research and development of coalbed methane drilling and mining technology are restricted. In this study, tectonic coal samples are remodeled with different particle sizes to test the mechanical parameters and loading resistivity. The research results show that the particle size and gradation of tectonic coal significantly impact its uniaxial compressive strength and elastic modulus and affect changes in resistivity. As the converted particle size increases, the uniaxial compressive strength and elastic modulus decrease first and then tend to remain unchanged. The strength of the single-particle gradation coal sample decreases from 0.867 to 0.433 MPa and the elastic modulus decreases from 59.28 to 41.63 MPa with increasing particle size. The change in resistivity of the coal sample increases with increasing particle size, and the degree of resistivity variation decreases during the coal sample failure stage. In composite-particle gradation, the proportion of fine particles in the tectonic coal sample increases from 33% to 80%. Its strength and elastic modulus increase from 0.996 to 1.31 MPa and 83.96 to 125.4 MPa, respectively, and the resistivity change degree decreases. The proportion of medium particles or coarse particles increases, and the sample strength, elastic modulus, and resistivity changes all decrease.

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Investigation of the kinetics of spontaneous combustion of the major coal seam in Dahuangshan mining area of the Southern Junggar coalfield, Xinjiang, China

Scientific Reports ◽

10.1038/s41598-020-79223-z ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Li Shen ◽

Qiang Zeng

Keyword(s):

Particle Size ◽

High Temperature ◽

Coal Seam ◽

Spontaneous Combustion ◽

Heating Temperature ◽

Characteristic Temperature ◽

Mining Area ◽

Particle Sizes ◽

Coal Oxidation ◽

Increasing Temperature

AbstractIn the present paper, with using diverse methods (including the SEM, the XRD, the TPO, the FTIR, and the TGA) , the authors analysed samples of the major coal seam in Dahuangshan Mining area with different particle sizes and with different heated temperatures (from 50 to 800 °C at regular intervals of 50 °C). The results from SEM and XRD showed that high temperature and high number of pores, fissures, and hierarchical structures in the coal samples could facilitate oxidation reactions and spontaneous combustion. A higher degree of graphitization and much greater number of aromatic microcrystalline structures facilitated spontaneous combustion. The results from TPO showed that the oxygen consumption rate of the coal samples increased exponentially with increasing temperature. The generation rates of different gases indicated that temperatures of 90 °C or 130 °C could accelerate coal oxidation. With increasing temperature, the coal oxidation rate increased, and the release of gaseous products was accelerated. The FTIR results showed that the amount of hydroxide radicals and oxygen-containing functional groups increased with the decline in particle size, indicating that a smaller particle size may facilitate the oxidation reaction and spontaneous combustion of coal. The absorbance and the functional group areas at different particle sizes were consistent with those of the heated coal samples, which decreased as the temperature rose. The results from TGA showed that the characteristic temperature T3 declined with decreasing particle size. After the sample with 0.15–0.18 mm particle size was heated, its carbon content decreased, and its mineral content increased, inhibiting coal oxidation. This result also shows that the activation energy of the heated samples tended to increase at the stage of high-temperature combustion with increasing heating temperature.

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