Temat: froth - Katalog OPAC zbiorów

Skocz do pozycji: 1.

Tytuł:: Effect of pH and time on hydrodynamic properties of dodecylamine
Autorzy:: Zhou, X.
Tan, Y. H.
Finch, J. A.
Powiązania:: https://bibliotekanauki.pl/articles/109853.pdf
Data publikacji:: 2018
Wydawca:: Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:: pH
dodecylamine
gas holdup
froth height
Frother function
Opis:: Gas holdup and froth height in the presence of dodecylamine (DDA, pKa = 10.63) are reported at three pH values. The results revealed a strong time effect for DDA: stability was reached at pH 3; not at natural pH, for example, gas holdup declining to the water only value; and at pH 11, while stability was reached quickly gas holdup was now less than in water alone indicating coalescence. In the first two cases, the time effect is attributed to loss of amine from the system as molecular amine, observed at natural pH as precipitates on the column wall. An argument for precipitation at pH < pKa is presented. At pH 11, coalescence is attributed to the oily nature of the molecular amine present as colloidal aggregates. Noting a difference in literature steady state gas holdup data at natural pH, it is speculated that varying steady states can be reached that corresponds to different levels of amine loss.
Źródło:: Physicochemical Problems of Mineral Processing; 2018, 54, 4; 1237-1244
1643-1049
2084-4735
Pojawia się w:: Physicochemical Problems of Mineral Processing
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 2.

Tytuł:: The effect of sodium carboxymethyl cellulose on the entrainment of zoisite in flotation
Autorzy:: Zhang, Zhengjun
Ou, Leming
Jin, Saizhen
Zhou, Hao
Powiązania:: https://bibliotekanauki.pl/articles/1448039.pdf
Data publikacji:: 2021
Wydawca:: Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:: entrainment
zoisite
froth stability
flotation
CMC flocculation
Opis:: During flotation, fine gangue minerals can enter the concentrate through mechanical entrainment, which seriously affects the quality of concentrate. In this work, the effect of sodium carboxymethyl cellulose (CMC) on the flotation performance of zoisite, a silicate mineral, was studied. The role of CMC in reducing zoisite entrainment was investigated by dynamic foaming tests, surface tension measurements, rheology measurements, sedimentation tests, and optical microscopy experiments. The flotation results showed that zoisite mainly entered the concentrate by entrainment; the addition of low dosages of CMC decreased zoisite entrainment and efficiently separated cassiterite from zoisite; moreover, the concentrate grade and recovery of SnO2 increased by 1.27 % and 5.63 %, respectively, by using CMC in closed-circuit flotation tests. Dynamic foaming studies on the two-phase and three-phase foam/froth revealed that the presence of CMC decreased the froth ability and froth stability, and greatly altered the three-phase froth structure. Basically, the bubbles in the foam were larger after adding CMC. For the two-phase foam, the change of foam property had little to do with surface activity and bulk viscosity. For the three-phase froth, the froth property was strongly affected by the interaction of CMC and zoisite. The results of the sedimentation test and microscopy experiment demonstrated that CMC can cause zoisite to flocculate and enlarge the particle size, which was the main reason for the decrease of froth stability and entrainment. This study indicates that the side effects of depressants should not be overlooked when discussing the role of depressants in flotation.
Źródło:: Physicochemical Problems of Mineral Processing; 2021, 57, 2; 34-47
1643-1049
2084-4735
Pojawia się w:: Physicochemical Problems of Mineral Processing
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 3.

Tytuł:: Effect of electrolyte addition on flotation response of coal
Autorzy:: Zhang, H.
Powiązania:: https://bibliotekanauki.pl/articles/109420.pdf
Data publikacji:: 2015
Wydawca:: Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:: coal flotation
salt solutions
zeta potential
induction time
froth stability
Opis:: In this study, the flotation of naturally hydrophobic coal particles in salt solutions with different cations (Na+, Ca2+, and Al3+) was investigated to clarify the flotation enhancement mechanism. The surface chemistry aspects were examined using the zeta potential measurements and bubble-particle attachment time experiments. The results of the flotation experiments showed that the presence of electrolytes in the flotation system clearly enhanced the flotation performance in a manner dependent on the type and concentration of the electrolytes. In the experiments, the AlCl3 and NaCl solutions showed the highest and the lowest flotation performance improvements, respectively. The zeta potential measurements showed that AlCl3 had a stronger influence on the surface charge of coal particles than CaCl2 or NaCl did. The induction time measurements indicated that the attachment decreased with increasing salt concentration and ionic valency state. In addition, abundant fine bubbles were generated in higher concentration salt solutions, particularly for the AlCl3 solutions, which prevented from the bubble coalescence and increased froth stability. It is concluded that the addition of salt solutions to a flotation system enhances the coal flotation performance, particularly for high-valence electrolyte solutions, which is attributed to the abundance of finer bubbles in the froth phase, depending on the type and concentration of the electrolyte.
Źródło:: Physicochemical Problems of Mineral Processing; 2015, 51, 1; 257-267
1643-1049
2084-4735
Pojawia się w:: Physicochemical Problems of Mineral Processing
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 4.

Tytuł:: Mechanism of the combined effects of air rate and froth depth on entrainment factor in copper flotation
Autorzy:: Wang, Lei
Xing, Yaowen
Wang, Jun
Powiązania:: https://bibliotekanauki.pl/articles/1449999.pdf
Data publikacji:: 2020
Wydawca:: Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:: froth flotation
copper
entrainment
air rate
froth depth
Opis:: The effect of air rate and froth depth on the entrainment factor in flotation has been extensively studied, but further investigation on the underlying mechanism for their effect is still required. In this study, flotation tests were performed at different air rates and froth depths in a 3 $dm^3$ continuously operated cell using an artificial copper ore. The results showed that entrainment factor was affected by both air rate and froth depth, and the combined effect of these variables on entrainment factor depended strongly on the particle size. The entrainment factor increased with either increasing air rate at a relatively shallow froth or decreasing froth depth at a relatively high air rate. At a very low air rate and deep froth, higher entrainment factor was observed for mid-size and coarse particles. When the entrainment factor was correlated to the effective liquid velocity at the pulp/froth interface, the results indicated that multiple mechanisms were responsible for the effect on entrainment factor. At a relatively high air rate and shallow froth depth, entrainment factor had a linear relationship with the interface effective liquid velocity, suggesting that drag force dominated the change in the entrainment factor when air rate and froth depth were varied. At a very low air rate and deep froth, the entrainment factor for fine particles was found to correlate strongly with the interface effective liquid velocity, while the entrapment of solid particles may be the main reason for the high entrainment factor for mid-size and coarse particles under this condition.
Źródło:: Physicochemical Problems of Mineral Processing; 2020, 56, 1; 43-53
1643-1049
2084-4735
Pojawia się w:: Physicochemical Problems of Mineral Processing
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 5.

Tytuł:: Nowe kierunki badań oraz rozwoju odczynników do flotacji węgla oraz minerałów niepolarnych
New directions in the research and development of reagents for flotation of coal and non-polar minerals
Autorzy:: Vidlar, J.
Pasiowiec, P.
Powiązania:: https://bibliotekanauki.pl/articles/318725.pdf
Data publikacji:: 2009
Wydawca:: Polskie Towarzystwo Przeróbki Kopalin
Tematy:: flotacja mułów węglowych
flotacja pianowa
odczynniki flotacyjne
odczynniki flotacyjne pochodzenia biologicznego
flotation of coal sludge
froth flotation
flotation reagent
flotation reagent of biological origin
Opis:: Podczas wydobycia oraz przeróbki mechanicznej węgla kamiennego oraz szeregu materiałów naturalnie hydrofobowych (grafit, siarka samorodna, talk, molibden, mika) powstaje i jest podawana przeróbce mechanicznej duża ilość drobnych ziaren surowca użytecznego (tzw. mułów), które występują w postaci zagęszczonych zawiesin wodnych lub zawiesin rozcieńczonych, traktowanych jako zanieczyszczone wody ściekowe. Najbardziej skuteczną metodą pozyskiwania użytecznych składników mineralnych z takich zawiesin wodnych (tzw. mułów flotacyjnych) jest flotacja pianowa. W ostatnich latach flotacja wykorzystywana jest coraz częściej jako metoda oczyszczania ścieków przemysłowych, zanieczyszczonych substancjami nieorganicznymi i organicznymi oraz jako metoda zagęszczania trudno sedymentujących mułów. W laboratoriach badawczych Wydziału Górnictwa i Geologii Vysokiej Skoly Banskiej w Ostrawie (HGF VŠB-TUO) przeprowadzono badania rozwojowe, których celem było uzyskanie pełnowartościowych odczynników flotacyjnych zastępując składniki ropopochodne składnikami pochodzenia biologicznego. Nowym perspektywicznym kierunkiem w zakresie opracowywania receptury odczynników flotacyjnych do flotacji mułów węglowych (uwzględniając skokowy rozwój branży produkcji biopaliw silnikowych-MEŘO) okazały się być badania oraz wdrożenia odczynników flotacyjnych na bazie komponentów odpadowych i produktów pośrednich tych biotechnologii. Skład nowo wytwarzanych odczynników flotacyjnych opiera się na doborze dostępnych składników pochodzenia biologicznego, mianowicie składników hydrofobowych i składników spieniających. Próby przemysłowe potwierdziły żądaną skuteczność technologiczną a zwłaszcza efektywność ekonomiczną zastąpienia stosowanych do tej pory odczynników flotacyjnych petrochemicznych nowo wytworzonymi odczynnikami bio.
During mining and mechanical processing of hard coal and some naturally hydrophobic materials (graphite, nugget sulphur, talcum, molybdenum, mica), a great quantity of small molecules of sludge of the extracted usable raw material is created and mechanically processed afterwards. The sludge appear as concentrated water slurry or diluted suspensions defined as polluted drain waters. The most efficient method to separate usable mineral components from water slurry (so-called "flotation sludge") is froth flotation. Recently the flotation is still more often used as a method of treatment of industrial waste, polluted with organic and non - organic substances, and as a concentration method for sludge of difficult sedimentation. In the research laboratories HGF VSB-TUO development researches has been done in order to find components of biological origin that are of full value and can replace currently used petrochemical components of flotation reagents. The research and implementations of flotation reagents based on waste components and indirect products of these technologies proved to be a new perspective direction in the area of defining flotation reagents for the flotation of coal sludge (taking into consideration an accelerated development of the branch of engine bio fuels production - MERO). The composition of new flotation reagents is based on the preferences of available components of biological origin, i.e. hydrophobic and frothing ones. The exploitation tests proved the required technological efficiency and, in particular, the economic benefit obtained by substituting the petrochemical flotation reagents used until now with new created reagents.
Źródło:: Inżynieria Mineralna; 2009, R. 10, nr 2, 2; 1-7
1640-4920
Pojawia się w:: Inżynieria Mineralna
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 6.

Tytuł:: Role of calcium and magnesium cations in the interactions between kaolinite and chalcopyrite in seawater
Autorzy:: Uribe, L.
Gutierrez, L.
Laskowski, J. S.
Castro, S.
Powiązania:: https://bibliotekanauki.pl/articles/109955.pdf
Data publikacji:: 2017
Wydawca:: Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:: froth flotation
chalcopyrite
chalcopyrite flotation
clay minerals
kaolinite
seawater
slime coating
Opis:: A number of flotation plants around the world have increased the use of seawater due to limited sources of fresh water. The aim of this research work is to study the role that Mg2+ and Ca2+ ions play in the interactions between kaolinite and chalcopyrite in seawater. In order to achieve this objective, the effect of kaolinite on flotation of chalcopyrite is studied over the pH range from 8 to 11, when flotation is carried out in seawater and in a 0.01M NaCl solution. The influence of calcium, magnesium, sodium, and potassium ions on the extent of depression by kaolinite is evaluated. The micro-flotation results indicate that chalcopyrite is depressed by kaolinite in both 0.01 NaCl solution and seawater. In the 0.01 NaCl solution, the depressing effect of kaolinite decreases as the pH increases from 8 to 11. However, the results obtained using seawater show that the depressing effect of kaolinite is similar to what is observed in a 0.01 NaCl solution only at pH values below 9, but above this pH kaolinite significantly affects the recovery of chalcopyrite. The results from experiments with using solutions containing individual cations show that the depressing action of kaolinite in the presence of Mg2+ and Ca2+ is more obvious at pH values of 9 and 10, respectively, which correlates with the pH values at which the first hydroxy-complexes of these divalent cations start forming. This seems to indicate that depressing effect of kaolinite on chalcopyrite in seawater may be related to formation of hydrolyzed species of calcium and magnesium. These species can induce heterocoagulation between kaolinite and chalcopyrite. The trends observed in the micro-flotation experiments are in good agreement with the results of the induction time measurements and slime coating tests.
Źródło:: Physicochemical Problems of Mineral Processing; 2017, 53, 2; 737-749
1643-1049
2084-4735
Pojawia się w:: Physicochemical Problems of Mineral Processing
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 7.

Tytuł:: Froth flotation of Aljustrel sulphide complex ore
Autorzy:: Sousa, R.
Futuro, A.
Pires, C. S.
Leite, M. M.
Powiązania:: https://bibliotekanauki.pl/articles/109732.pdf
Data publikacji:: 2017
Wydawca:: Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:: froth flotation
mineral liberation
flotation reagents
complex sulphide ore
Opis:: Froth flotation of copper-zinc-lead ores is a complex process based on similar metallurgy processing and strong interactions between chalcopyrite and sphalerite. These types of ores represent 15% of the world production and 7.5% of copper deposits all over the world. In the present study, an attempt is made to assess the feasibility of froth flotation of a complex sulphide ore, where the effect of liberation grade as well as depressant, collector and frother dosage was studied. Copper flotation is dependent on the mineral liberation grade, which is significantly related with the size distribution. It was shown that longer grinding time increased the Cu grade but decreased the copper recovery due to the presence of very fine particles. Lime and sodium metabisulphite, used as depressants, allowed to achieve a good flotation performance. It was shown that for this type of ore lower dosage of the collector should be applied. Finally, a higher frother dosage led to a greater selectivity and reduced entrainment of very fine particles, but also caused low kinetic ratio and low recovery of valuable minerals. A well-defined flotation objective was imperative for a good liberation grade and reagents dosage selection, mainly for complex sulphide ores. A useful contribute was given to a better technical understanding of flotation of a complex sulphide ore from the Moinho deposit.
Źródło:: Physicochemical Problems of Mineral Processing; 2017, 53, 2; 758-769
1643-1049
2084-4735
Pojawia się w:: Physicochemical Problems of Mineral Processing
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 8.

Tytuł:: Wstępne badania hydrauliki współprądowego, półkowego absorbera z pianą dynamiczną
Initial experimental research on the hydraulics of froth co-current column
Autorzy:: Sarré, P.
Gierczycki, A.
Powiązania:: https://bibliotekanauki.pl/articles/2073102.pdf
Data publikacji:: 2015
Wydawca:: Stowarzyszenie Inżynierów i Techników Mechaników Polskich
Tematy:: kolumna półkowa
piana dynamiczna
powierzchnia międzyfazowa
opory przepływu
wymiana masy
shelf column
dynamic froth
interfacial area
pressure drop
mass transfer
Opis:: Przeprowadzono wstępne badania doświadczalne hydrauliki współprądowej kolumny pianowej. Określono rzeczywisty czas przebywania cieczy i gazu w obrębie piany dynamicznej. Obliczono w sposób przybliżony wielkość powierzchni międzyfazowej. Wyznaczono spadki ciśnienia gazu na półce suchej, mokrej oraz w warstwie piany. Przedstawiona kolumna ze względu na swoje walory w postaci relatywnie dużej powierzchni międzyfazowej oraz stabilnej pracy przy wysokim obciążeniu cieczą powinna znaleźć zastosowanie w przemysłowych procesach wymiany masy.
Experimental studies on hydraulics of froth co-current column were performed. Gas and liquid real residence time in the froth was determined. Gas and liquid interfacial area was approximately calculated. Gas pressure drop across the dry and wet shelf as well as in the froth layer were measured. The presented column due to its advantageous features, i.e. relatively large gas – liquid interfacial area and stable work under high wetting density should be applied in industrial mass transfer operations.
Źródło:: Inżynieria i Aparatura Chemiczna; 2015, 3; 117--118
0368-0827
Pojawia się w:: Inżynieria i Aparatura Chemiczna
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 9.

Tytuł:: Specific ion effect of chloride salts on collectorless flotation of coal
Autorzy:: Ozdemir, O.
Powiązania:: https://bibliotekanauki.pl/articles/110238.pdf
Data publikacji:: 2013
Wydawca:: Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:: flotation
coal
salt
froth stability
ion-specific effect
Opis:: Separation of naturally hydrophobic particles, such as coal, by flotation is known to be enhanced with the addition of salt solutions into the system. In this study, the flotation of bituminous coal in the presence of NaCl, KCl, CaCl2 and MgCl2 without use of any flotation chemicals was investigated in detailed. In addition, zeta potential and foam stability tests were performed. The results from this study showed that the flotation behaviour of coal was influenced by these dissolved salts, and determined by the specific effect of these ions, while MgCl2 and KCl solutions showed the highest and the lowest flotation performance improvements, respectively. The ash content of the products also increased with the salt concentration. This can be attributed to the entrainment of the ash minerals in the salt solutions, particularly at higher salt concentrations. Meanwhile, the froth stability tests at 1 M salt concentration also indicated that there is a correlation between the flotation recovery and stability profile of the froth. These results also clearly indicated that Na+, K+, Ca2+, Mg2+ ions have a strong ion specific effect on the flotation recovery of the coal particles, and there is an optimum salt concentration to produce a clean coal in these salt solutions.
Źródło:: Physicochemical Problems of Mineral Processing; 2013, 49, 2; 511-524
1643-1049
2084-4735
Pojawia się w:: Physicochemical Problems of Mineral Processing
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 10.

Tytuł:: Effect of air flow rate and froth depth on the flotation performance : an industrial case study in a 10 m3 cell
Autorzy:: Ostadrahimi, Mahdi
Farrokhpay, Saeed
Pirmoradi, Saeed
Noparast, Mohamad
Powiązania:: https://bibliotekanauki.pl/articles/2146876.pdf
Data publikacji:: 2022
Wydawca:: Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:: entrainment
bubble coalescence
air flow rate
froth depth
Opis:: The main purpose of the froth zone in flotation is to transport all the valuable particles from the pulp zone into the concentrate. However, in practice, a complete recovery of these particles is rarely achieved since some of them are detachment from the bubbles and return to the pulp zone. While this is an important topic in the mineral flotation industry, the previously published papers are mainly limited to small laboratory scales. Therefore, this study aimed to examine the effect of two main flotation variables (air flowrate and froth depth) on the flotation of iron ore in a 10 m3 industrial scale cell. It was found that, when the air flowrate increased from 45 to 146 m3/h, the velocity of the bubble coalescence also increased. In addition, when the froth depth increased from 5 to 30 cm, the product grade showed on average 2 unit increase (for instance, from 12% to 14%) due to the detachment of particles and liquid drainage. It was also found that the flotation concentrates recovery decreased with the increasing froth depth and air flowrate.
Źródło:: Physicochemical Problems of Mineral Processing; 2022, 58, 5; art. no. 154852
1643-1049
2084-4735
Pojawia się w:: Physicochemical Problems of Mineral Processing
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 11.

Tytuł:: On the selection of the coarsest size class in flotation rate characterizations
Autorzy:: Orellana, Francisca
Rivera, Marcelo
Benítez, Matías
Belmonte, Karyn
Vinnett, Luis
Powiązania:: https://bibliotekanauki.pl/articles/24603662.pdf
Data publikacji:: 2023
Wydawca:: Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:: flotation kinetics
froth flotation
coarse particles
flotation rate distribution
Opis:: This paper studies size-by-size batch flotation kinetics for the separation of Cu at particle sizes +75 μm, investigating the responses in the -150/+75 μm, -212/+150 μm, -300/+212 μm, -355/+300 μm and +355 μm size fractions. The kinetic results were analyzed to identify classes limited by the maximum achievable recovery or low flotation rates. Combinations of these classes were investigated, emulating the selection of the coarsest size in a kinetic study. The impact of compositing size classes was discussed, emphasizing implications in the identification of difficult-to-float components. The -212/+75 μm classes reached steady recoveries at long flotation times, whereas the -355/+212 μm classes presented sustained increasing recoveries at extended flotation times. Flotation rate distributions in the -212/+75 μm classes exhibited mound-shaped distributions, indicating low fractions of rate constants close to zero (R∞-limited case). Conversely, the -355/+212 μm classes presented reverse J-shaped distributions, with a high fraction of valuable minerals with flotation rates close to zero (rate-limited case). Combining several size classes in the definition of the coarsest size fraction in kinetic characterizations proved to hide the flotation patterns of the less massive constituents (+212 μm classes). The +75 μm and +150 μm cumulative retained classes trended towards steady recoveries, consistently leading to mounded flotation rate distributions. This study highlighted the need for reliable methodologies to select size fractions in kinetic characterizations, as their arbitrary definitions may lead to a misinterpretation of the mineral losses when compositing classes with different flotation responses.
Źródło:: Physicochemical Problems of Mineral Processing; 2023, 59, 5; art. no. 176950
1643-1049
2084-4735
Pojawia się w:: Physicochemical Problems of Mineral Processing
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 12.

Tytuł:: Column flotation performance prediction: PCA, ANN and image analysis-based approaches
Autorzy:: Nakhaei, Fardis
Irannajad, Mehdi
Mohammadnejad, Sima
Powiązania:: https://bibliotekanauki.pl/articles/109518.pdf
Data publikacji:: 2019
Wydawca:: Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:: image analysis
column flotation
froth features
performance
prediction
PCA
ANN
Opis:: The flotation froth surface appearance includes remarkable information, which can be employed as a helpful index for the qualitative evaluation of the process efficiency. Image analysis is a practical technology for the sake of achieving process related information that can be employed in expert controllers in order to amend flotation performance. In this paper, the intelligent modelling of relationship between froth characteristics and the metallurgical performance in a pilot column flotation of iron ore was established. Column flotation tests were carried out at a wide range of operating conditions and the froth features along with the metallurgical performances were specified for each run. The artificial intelligence models suggested for the performance parameters prediction include (1) multi-layer back propagation neural network (BPNN), (2) hybrid BPNN with principal component analysis (PCA). The hybrid network was on the basis of the PCA employment in order to decrease the number of variables to be given as input for BPNN. The relationships between the froth features and metallurgical performance factors were successfully modelled via the use of the two methods. The simulation results revealed that the prediction precision of BPNN model on the basis of all the data was relatively higher than the estimation precision of BPNN based on PCA algorithm. The Hybrid BPNN model that was trained by the pre-processed database of measurements achieved from the PCA can be considered a robust method when training time is of paramount importance in objectives of proces control.
Źródło:: Physicochemical Problems of Mineral Processing; 2019, 55, 5; 1298-1310
1643-1049
2084-4735
Pojawia się w:: Physicochemical Problems of Mineral Processing
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 13.

Tytuł:: Prediction of on-line froth depth measurement errors in industrial flotation columns: a promising tool for automatic control
Autorzy:: Nakhaei, F.
Irannajad, M.
Powiązania:: https://bibliotekanauki.pl/articles/110715.pdf
Data publikacji:: 2013
Wydawca:: Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:: prediction
accuracy
froth height
Kalman filter
error
Opis:: The pulp-froth interface position is important from a metallurgical point of view because it determines the relative importance of the cleaning and the collection zones. The pulp-froth interface position is measured based on variations of specific gravity, temperature or conductivity between the two zones to locate the pulp froth interface position. In this study, the pressure measurements are used to calculate the values of the froth layer height. These two meters are installed in the upper part of the column at 1.4 m and 2.4 m respectively, from the top of the column. Methods using pressure gauges are commonly used in industrial operations Even though their accuracy is limited (due to assumptions of uniformity of the pulp and froth density), and they always have some error. In the Sarcheshmeh copper industrial plant (Iran), a float was installed near the column with 2.5 m height that was calibrated to 5 cm intervals in order to determine the more exact forth height and compare it with the recorded froth height in control room. In this paper, an algorithm based on Kalman Filter is presented to predict on-line froth height errors using two pressure gauges. This research is based on the industrial real data collection for evaluating the performance of the presented algorithm. The quality of the obtained results was very satisfied. The RMS errors of prediction froth height errors was less than 0.025 m.
Źródło:: Physicochemical Problems of Mineral Processing; 2013, 49, 2; 757-768
1643-1049
2084-4735
Pojawia się w:: Physicochemical Problems of Mineral Processing
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 14.

Tytuł:: Perspectives from literature on the influence of inorganic electrolytes present in plant water on flotation performance
Autorzy:: Manono, M. S.
Corin, K.
Wiese, J.
Powiązania:: https://bibliotekanauki.pl/articles/110721.pdf
Data publikacji:: 2018
Wydawca:: Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:: electrolytes
flotation reagents
froth stability
physicochemical interaction
water quality
Opis:: The interaction of inorganic electrolytes with reagents in the flotation of sulphidic PGM bearing ores is not well explored. It has been shown that specific inorganic electrolytes such as Ca2+ and SO42- can affect the wettability of gangue minerals. These could also hinder the adsorption of collectors onto valuable minerals and concurrently enhance or retard froth stability. This presents a challenge as regards understanding what the overarching or controlling mechanisms of interaction between electrolytes, reagents and minerals are as well as predicting how flotation performance will be affected. This review shows that studies in literature have simplified the question of electrolyte-reagent-mineral interactions and that current approaches have not provided fundamental solutions to the challenge of water quality. It is proposed that the complexity of the flotation system requires an in-depth knowledge of the individual electrolyte-reagent-mineral interactions so as to establish whether there are any dominant or synergistic interactions. Such in-depth knowledge should enable the development of pulp chemistry control measures against water quality variations in flotation.
Źródło:: Physicochemical Problems of Mineral Processing; 2018, 54, 4; 1191-1214
1643-1049
2084-4735
Pojawia się w:: Physicochemical Problems of Mineral Processing
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 15.

Tytuł:: Water quality effects on a sulfidic PGM ore: Implications for froth stability and gangue management
Autorzy:: Manono, M. S.
Corin, K.
Wiese, J.
Powiązania:: https://bibliotekanauki.pl/articles/110603.pdf
Data publikacji:: 2018
Wydawca:: Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:: entrainment
water quality
froth stability
electrolytes
Depressant behavior
Opis:: Polysaccharide depressants play a crucial role in the flotation of sulfidic PGM bearing ores as they prevent naturally floatable gangue (NFG) from reporting to the concentrate. This action is regarded as critically important because less dilution of the concentrate means lower costs for downstream processes. However, abnormal water conditions such as high concentrations of ions in the flotation system can modify the selectivity of these depressants. It is well known that the existence of selected electrolytes in water can alter the behaviour of some polysaccharide depressants by enhancing their adsorption onto gangue minerals and thereby prevent naturally floatable gangue from moving into the froth phase. Concurrently these same electrolytes may enhance frothability owing to their stabilising effect on the bubbles within the system. Plant water at various ionic strengths was investigated against sodium carboxymethyl cellulose (CMC) dosages in order to understand electrolyte-depressant interactive effects during the flotation of a Merensky ore in a batch flotation cell, using entrainment, rate of NFG recovery, and total gangue recovery as proxies. The study showed that the NFG recovery per unit mass of water decreased with increasing ionic strength at all CMC dosages, however the total amount of gangue reporting to the concentrate increased with increasing ionic strength at all CMC dosages. Thus, this paper considers the effects of both ionic strength and CMC dosage within flotation. It further investigates whether any interactive effects exist between froth stability and entrainment when considered simultaneously.
Źródło:: Physicochemical Problems of Mineral Processing; 2018, 54, 4; 1253-1265
1643-1049
2084-4735
Pojawia się w:: Physicochemical Problems of Mineral Processing
Dostawca treści:: Biblioteka Nauki

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