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Wyszukujesz frazę "flotation kinetics" wg kryterium: Temat


Tytuł:
Wyznaczanie charakterystyk statycznych flotowników przepływowych wielokomorowych
Determination of static characteristics of multichamber flow flotation machines
Autorzy:
Kaula, R.
Kalinowski, K.
Powiązania:
https://bibliotekanauki.pl/articles/112981.pdf
Data publikacji:
2017
Wydawca:
STE GROUP
Tematy:
modele kinetyki flotacji
współczynnik prędkości flotacji
funkcja gęstości rozkładu flotowalności ziaren węgla
charakterystyki statyczne flotowników przepływowych
models of the kinetics flotation
coefficient of the flotation velocity
density function of the distribution of the coal particles flotability
static characteristics of the flow flotation machines
Opis:
Wyznaczanie charakterystyk statycznych procesu wzbogacania w przemysłowych maszynach flotacyjnym jest zagadnieniem trudnym ze względu na wpływ wielu parametrów na przebieg procesu. Przyjmuje się, że parametrem który zawiera informacje o czynnikach wpływających na proces jest współczynnik prędkości flotacji k ziaren, charakteryzujący sie określonym rozkładem flotowalności ziaren f(k). Funkcję tego typu uzyskuje się na podstawie przebiegu kinetyki wydzielania się masy składników nadawy w procesie flotacji cyklicznej. Wyznaczenie funkcji f(k) realizowane jest pośrednio poprzez model matematyczny przebiegu kinetyki flotacji m(t). Wyznaczone parametry modelu kinetyki są równocześnie parametrami modelu funkcji gęstości rozkładu flotowalności ziaren węgla. Na podstawie wcześniejszych prac autorzy wykazali, że model rozkładu trójkątnego funkcji f(k) dobrze charakteryzuje niejednorodność nadawy. Korzystając z rozkładu flotowalności ziaren można wyznaczyć rozkład zawartości popiołu w zależności od zmian współczynnika prędkości flotacji. Na podstawie tych zależności można wyznaczyć charakterystyki statyczne flotownika przepływowego. W artykule wyznaczono charakterystyki statyczne jednokomorowego i wielokomorowego flotownika przepływowego. Otrzymane na podstawie badań symulacyjnych charakterystyki statyczne wychodu koncentratu i zawartości popiołu w koncentracie w zależności od zmian natężenia dopływu powietrza, są zbieżne do charakterystyk wyznaczonych, przez autorów, na podstawie badań flotowników przemysłowych. Znajomość charakterystyk gęstości rozkładu frakcji wraz z rozkładem zawartości popiołu umożliwi lepszą ocenę zjawisk zachodzących w procesie wzbogacania. Wyznaczone na podstawie tych modeli charakterystyki statyczne przepływowych flotowników jedno i wielokomorowych mogą być wykorzystywane w projektowaniu systemów sterowania procesu flotacji kopalin.
Determining the static characteristics of the enrichment process in industrial flotation machines is a difficult problem because of the influence of many parameters on the process. It is assumed that a parameter which contains information about the factors affecting the process is the velocity coefficient k of the flotation particles. This parameter is characterized by distribution of the particles flotability f(k). The function of this type is obtained based on the course of the kinetics of the mass feed components in the batch flotation process. Determining a function f (k) is carried out indirectly by a mathematical model based on the course of flotation kinetics m(t). The determined parameters of the kinetics model are also the parameters of the model of the distribution density function of the coal particles flotability. Based on previous works has been shown that the feed heterogeneity can be well characterized by the model of the triangular distribution function f (k). Using the distribution of the particles flotability it can determine the distribution of the ash content depending on changes of the coefficient of the flotation velocity. On the basis of these dependencies can be determined the static characteristics of the flow flotation machine. The static characteristics of single and multi-chamber of the flow flotation machine in the paper have been presented. Obtained on the basis of simulation the static characteristics of the concentrate recovery and ash content in the concentrate depending on changes in the intensity of the air are similar to the characteristics determined by the authors based on the research of the industrial flotation machines. Knowledge of the characteristics of the density of the fractions distribution together with the distribution of ash content will allow a better assessment of the phenomena occurring in the enrichment process. The static characteristics of the single and multi-chamber flotation flow machines determined on the basis of these models can be used in the design of systems of the process control of the minerals flotation.
Źródło:
Systemy Wspomagania w Inżynierii Produkcji; 2017, 6, 2; 150-159
2391-9361
Pojawia się w:
Systemy Wspomagania w Inżynierii Produkcji
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Verification of flotation kinetics model for triangular distribution of density function of flotability of coal particles
Weryfikacja modelu kinetyki flotacji dla trójkątnego rozkładu funkcji gęstości flotowalności ziaren węgla
Autorzy:
Kalinowski, K.
Kaula, R.
Powiązania:
https://bibliotekanauki.pl/articles/218720.pdf
Data publikacji:
2013
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
modele kinetyki flotacji
współczynnik prędkości flotacji
funkcja gęstości rozkładu frakcji
flotowniki przemysłowe
models of the flotation kinetics
coefficient of flotation velocity
distribution density function of the fraction
industrial flotation machine
Opis:
Parameters of flotation kinetics model with a gamma and a triangular distribution have been determined based on the batch coal flotation experiments. Analyses were carried out at different values of the intensity of aeration air. The results of example analyses are presented in tables and graphs form. It follows from the carried out study on the mathematical models of flotability coefficient distribution of particles of examined coal samples that the triangular distribution model is statistical equivalent to the gamma flotability distribution. The assumption of the triangular distribution enables determination of the density function of distribution of fraction in the industrial flotation machines. Knowledge of this function will allow better evaluation of the phenomena occurring in the process of enrichment. It may be one of the basic information used in the supervisory control system.
Na podstawie badań eksperymentalnych flotacji cyklicznej węgla wyznaczono parametry modelu kinetyki flotacji z rozkładem gamma i trójkątnym. Analizy przeprowadzono przy różnych wartościach natężenia powietrza do aeracji. Wyniki przykładowych analiz przedstawiono tabelarycznie i w postaci wykresów. Z przeprowadzonych badań nad modelami matematycznymi rozkładu współczynnika flotowalności ziaren badanych próbek węgla wynika, że model o rozkładzie trójkątnym statystyczne jest równoważny rozkładowi flotowalności gamma. Przyjęcie rozkładu trójkątnego umożliwi wyznaczenie funkcji gęstości rozkładu frakcji we flotownikach przemysłowych. Znajomość tej funkcji pozwoli na lepszą ocenę zjawisk zachodzących w procesie wzbogacania. Może stanowić jedną z podstawowych informacji wykorzystywanych w nadrzędnym systemie sterowania.
Źródło:
Archives of Mining Sciences; 2013, 58, 4; 1279-1287
0860-7001
Pojawia się w:
Archives of Mining Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The Effect of Sodium Hexametaphosphate on Natural Flotation Kinetics of Talc Ore
Wpływ heksametafosforanu sodu na kinetykę flotacji naturalnej rudy talkowej
Autorzy:
Brezani, I.
Sisol, M.
Marcin, M.
Powiązania:
https://bibliotekanauki.pl/articles/318773.pdf
Data publikacji:
2018
Wydawca:
Polskie Towarzystwo Przeróbki Kopalin
Tematy:
flotacja pianowa
flotowalność naturalna
depresor
kinetyka flotacji
ruda talku
froth flotation
natural floatability
flotation depressor
flotation kinetics
talc ore
Opis:
Ground high-grade ore with the d80 of 150 μm was subjected to a series of batch laboratory flotation tests, aimed at determining the natural flotation kinetics of talc mineral, using Methyl isobutyl carbinol (MIBC) frother as the only reagent. Classical first-order flotation model was used and the flotation kinetics are interpreted using the ultimate recovery (R∞) and flotation rate constant (k). Results are then compared with the kinetics of flotation in the presence of different dosages of the frother, Sodium hexametaphosphate (SHMP) and a mixture of SHMP and Soluble starch (SS) in various ratios. The design of experiment (DoE), evaluated using the Analysis of variance (ANOVA) test for multiple factors was used to calculate the statistical significance of the individual factors on the outcomes of the flotation tests – yield of the froth product, talc concentrate grade, talc recovery and flotation kinetics of both talc and gangue minerals. The effect of SHMP on the flotation kinetics of talc and gangue minerals in terms of affecting the R∞ and k parameters is here discussed in greater detail. Although both SHMP and SHMP/SS mixture was found to improve the overall grade of the talc concentrate, this was achieved at the expense of significantly lower recoveries of the valuable mineral.
Zmielona wysokowartościowa ruda o ziarnie podziałowym d80 = 150 μm została poddana serii laboratoryjnych prób flotacji, mających na celu określenie kinetyki flotacji naturalnej minerałów talku, w obec-ności jedynego środka zbierającego metylo-izobutylokarbinol (MIBC). Zastosowano klasyczny model flotacji pierwszego rzędu gdzie kinetykę flotacji interpretuje się za pomocą współczynnika uzysku R∞ i stałej szybkości flotacji (k). Wyniki porównano z kinetyką flotacji w obecności różnych dawek spieniacza, heksametafosforanu sodu (SHMP) i mieszaniny SHMP i rozpuszczalnej skrobi (SS) w różnych proporcjach. Plan eksperymentu (DoE), oceniono za pomocą analizy wariancji (ANOVA) dla wielu czynników użyto do obliczenia istotności statystycznej parametrów flotacji - wydajność produktu pianowego, zawartość talku, uzysk talku i kinetyka flotacji zarówno minerałów talku, jak i skały płonnej. Wpływ SHMP na kinetykę flotacji minerałów talku i skały płonnej na parametr R∞ i k są omówione bardziej szczegółowo. Chociaż stwierdzono, że dla obu mieszanek SHMP i SHMP / SS poprawie uległ stopień koncentracji talku odbyło się to jednak kosztem znacząco niższych wartości uzysku cennego minerału.
Źródło:
Inżynieria Mineralna; 2018, R. 19, nr 1, 1; 125-130
1640-4920
Pojawia się w:
Inżynieria Mineralna
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Surface roughness in bubble attachment and flotation of highly hydrophobic solids in presence of frother – experiment and simulations
Autorzy:
Kosior, D.
Kowalczuk, P. B.
Zawala, J.
Powiązania:
https://bibliotekanauki.pl/articles/109319.pdf
Data publikacji:
2018
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
surface roughness
attachment
flotation
kinetics
frother
Opis:
In this paper, the kinetic of the three-phase contact (TPC) formation and the flotation recovery of highly hydrophobic solids with different surface roughness were studied in pure water and aqueous solutions of n-octanol. The surface roughness varied between 1 to 100 μm. It was found that there was a strong influence of surface roughness on both kinetics of TPC formation and flotation. The time of three phase contact formation and flotation rate were much faster for rough surfaces in both water and aqueous solutions of frother. Irrespective of the surface roughness, at above a certain frother dose, the attachment time increased and the flotation rate decreased. It was related to the presence of air at the hydrophobic solid surfaces. The mechanism of this prolongation of the time of TPC formation at the solid surfaces with different roughness due to the frother overdosage was discussed, and the experimental data were confirmed by numerical simulations.
Źródło:
Physicochemical Problems of Mineral Processing; 2018, 54, 1; 63-72
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Physicochemical study of dye removal using electro-coagulation-flotation process
Autorzy:
El-Hosiny, F. I.
Abdel-Khalek, M. A.
Selim, K. A.
Osama, I.
Powiązania:
https://bibliotekanauki.pl/articles/109865.pdf
Data publikacji:
2018
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
electro-flotation
electrocoagulation
dyes
wastewater
kinetics
thermodynamics
Opis:
The performance of electro-flotation with aluminum electrodes for the removal of different dyes from synthetic aqueous solutions and real wastewater was studied. Parameters affecting the electro-coagulation-flotation process, such as pH, initial dye concentration, treatment time and temperature were investigated. The maximum dye removal from synthetic solutions was achieved at pH 7. The order of the dye removals is nonionic>cationic>anionic. The removal process follows pseudo first-order kinetics and the adsorption follows both physical and chemical adsorptions which is exothermic. Negative values of entropy change, ΔS°, and Gibbs free energy change, ΔG°, indicate that this adsorption process is spontaneous and less favorable at high temperatures. Treatment of a real wastewater from textile dyeing factory showed that the removal efficiency was ranging between 92-99% for all constituents. The energy consumption is 0.0167 kWh/dm3.
Źródło:
Physicochemical Problems of Mineral Processing; 2018, 54, 2; 321-333
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
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
Artykuł
Tytuł:
Lignite cleaning in NaCl solutions by the reverse flotation technique
Autorzy:
Zhang, H.
Liu, Q.
Powiązania:
https://bibliotekanauki.pl/articles/110516.pdf
Data publikacji:
2015
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
lignite
reverse flotation
NaCl
kinetics
coal preparation
Opis:
A cleaning possibility of low (BD) and high ash content (IM) lignites in NaCl solutions using a reverse flotation technique was studied. Preliminary test results indicated that BD lignite cannot be cleaned effectively in the traditional manner because gangue was floated first rather than a combustible material. Further studies indicated that the lignite cleaning in NaCl solutions using the reverse flotation technique is possible. However, a large quantity of dodecyl amine hydrochloride (DAH) was required. A lower ash content in a concentrate can be obtained by addition of NaCl. A concentrate yield can be im-proved by addition of starch. Under the test conditions, for BD lignite with the ash content in the feed 15.19%, the ash content in the concentrate 11.44% and the concentrate yield 67.38% were obtained. Similarly, for IM lignite with the ash content in the feed 57.40%, the ash content in the concentrate 32.90% and the concentrate yield 25.08% were obtained. The flotation rate constant k and maximum ash recovery ε∞ significantly increased with the NaCl concentration.
Źródło:
Physicochemical Problems of Mineral Processing; 2015, 51, 2; 695-706
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Kinetic separation curves based on process rate considerations
Autorzy:
Drzymala, J.
Ratajczak, T.
Kowalczuk, P. B.
Powiązania:
https://bibliotekanauki.pl/articles/110027.pdf
Data publikacji:
2017
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
separation
flotation
kinetics
separation curves
process rate
Opis:
There are many graphical representations of separation results involving time as a crucial parameter determining the kinetics of a process. The graphical representations of results of separation are usually in the form of 2D plots relating two parameters which one of them is time. Time can also be utilized as a complex parameter such as a process rate. The plots involving time are called kinetic curves. Theoretically, the number of kinetic curves is infinite. The basic process kinetic curves, relating either yield (or recovery) and time can be modified to obtain numerous local and global efficiency curves. The global efficiency kinetic curves provide characteristic constants which do not change with the time and yield of a process. In this paper the local and global efficiency plots were created using experimental data which followed the so-called first order kinetics. It was shown that the integral 1st order kinetic equation provided the kinetic constant k which was numerically identical with the 1st order specific rate v, while their units were different (k, 1/min; v, %/(%·min). The global efficiency parameters plotted versus the maximum yield provided another type of plot, which can be called the limits kinetic curve. The limits kinetic curves are very useful for characterizing, quantification and classification of separation systems. The limits kinetic curves can be normalized providing one universal curve with a characteristic point, for instance, v50 indicating the specific rate (or kinetic) constant at the maximum recovery equal to 50%. The mathematical equation of the normalized limits kinetic curve was given in the paper.
Źródło:
Physicochemical Problems of Mineral Processing; 2017, 53, 2; 983-995
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Kinetic modelling of flotation column and Jameson cell in coal
Autorzy:
Karaca, Sevgi
Ucar, Ali
Sahbaz, Oktay
Powiązania:
https://bibliotekanauki.pl/articles/2146872.pdf
Data publikacji:
2022
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
coarse particle
flotation column
Jameson cell
kinetics
particle size
Opis:
Physical enrichment technologies can be used worldwide in various coal washing plants to enrich up to 500 μm particle size. Conversely, coals smaller than this are discarded as waste, causing storage and environmental issues. In this regard, studies on coal below 500 μm in Turkey have recently acquired attraction. The Jameson flotation cell and flotation column, which have many uses worldwide but are not used throughout the plant in Turkey, were used to investigate the separation possibilities of coals below 500 μm. In the study, the flotation column and Jameson cell performances for three different particle sizes (-500+300, -300+212 and -212+106 μm) were compared. For the first time, both machines operated in a negative bias condition. In addition, the flotation kinetics of the machines were modelled with some critical operating parameters. Models illustrating the main and multiple effects of the parameters were developed using the data derived from the experimental results, and the models were statistically significant at the 95% confidence level. In the experiments performed with both flotation machines, the flotation rate increases with the decrease in particle size in general. According to the results, the velocity increase in the Jameson cell was 0.0050-0.0075 min-1 compared to the flotation column in the experiments performed in the size range of -500+300 μm, and the flotation rate constant increased approximately twice. In the size range of -212+106 μm, the difference became larger, and the flotation rate of the Jameson cell increased up to six times with a difference of 0.0450-0.0500 min-1.
Źródło:
Physicochemical Problems of Mineral Processing; 2022, 58, 5; art. no. 152848
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Flotation kinetics and thermodynamic behavior of chalcopyrite and pyrite in high alkaline systems
Autorzy:
Yan, H.
Yuan, Q.
Zhou, L.
Qiu, T.
Ai, G.
Powiązania:
https://bibliotekanauki.pl/articles/110078.pdf
Data publikacji:
2018
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
flotation kinetics
pyrite
chalcopyrite
flotation separation
high alkaline
microcalorimetry
Opis:
The monomineral flotation test and microcalorimetry were used to study the flotation kinetics and thermodynamic behavior of chalcopyrite and pyrite in high alkaline systems of lime and NaOH. The results showed that in these systems there were less hydrophilic substances on the chalcopyrite surface, so that the apparent activation energy of sodium butyl xanthate (SBX) adsorption on chalcopyrite surface was low. This promoted the adsorption of SBX and increased the flotation rate and recovery of chalcopyrite. In contrast, the hydrophilic Fe(OH)3 and SO42- formed by oxidation on the pyrite surface increased the adsorption activation energy of SBX. Thus, the flotation rate and recovery of pyrite were lower. Moreover, in the lime high alkaline system, the hydrophilic calcium film generated on the pyrite surface further hindered the adsorption of SBX, thereby further inhibiting pyrite in this environment. In other words, the lime high alkaline environment increased the apparent activation energy difference of SBX adsorption between chalcopyrite and pyrite compared to the NaOH system, facilitating the flotation separation of chalcopyrite and pyrite. The results can help with the theoretical research of flotation separation of other minerals, and provide guidance for developing low alkaline and lime-free pyrite depressants.
Źródło:
Physicochemical Problems of Mineral Processing; 2018, 54, 3; 901-910
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Evaluation of sodium petroleum sulfonates with different molecular weights for flotation of kyanite ore
Autorzy:
Chen, B. Z.
Gao, H.
Li, Y.
Jin, J.
Ren, Z.
Wang, W.
Powiązania:
https://bibliotekanauki.pl/articles/109492.pdf
Data publikacji:
2017
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
evaluation
sodium petroleum sulfonate
kyanite
flotation kinetics
entrainment
Opis:
The flotation performance of sodium petroleum sulfonates with different molecular weights was evaluated for flotation of a kyanite ore, by investigating valuable mineral recovery-grade, flotation kinetics and gangue entrainment. The results indicated that the higher molecular weight of agent, the higher final cumulative kyanite recovery was, with the maximum value of 72% being obtained with KY-3 with the molecular weight of 438. The final cumulative kyanite grade initially increased, and then decreased with the molecular weight increasing. In other words, the maximum final cumulative kyanite grade (i.e. 89.05%) was obtained with KY-2 with the molecular weight of 392. The kyanite flotation kinetics followed the first order kinetics well, while the modified flotation rate constant showed a decreasing trend after the initial increase as the molecular weight increased. In addition, the overall entrainment degree decreased with decreasing molecular weight of sodium petroleum sulfonates. The use of KY-2 in kyanite flotation was an attractive option in comparison with KY-1 and KY-3.
Źródło:
Physicochemical Problems of Mineral Processing; 2017, 53, 2; 956-968
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Ekologiczne aspekty związane z efektami wysokociśnieniowego rozdrabniania w prasach walcowych
Environmental Aspects Connected with Effects of High-pressure Comminution in Roller Presses
Autorzy:
Saramak, D.
Tumidajski, T.
Gawenda, T.
Naziemiec, Z.
Powiązania:
https://bibliotekanauki.pl/articles/1819049.pdf
Data publikacji:
2013
Wydawca:
Politechnika Koszalińska. Wydawnictwo Uczelniane
Tematy:
ekologiczne aspekty
prasy walcowe
models
flotation
kinetics
Opis:
The aim of the paper is an analysis of work effects of HPGR-based technological circuits in industrial mineral processing operations. High-pressure grinding rolls technology is currently one of the most effective methods of raw materials comminution both from the scope of the crushing products quality as well as the environmental effects associated with a lower environmental nuisance. In the first part of investigations the effective control of the particle size distribution of crushing products through the proper selection of operating pressure in the press. In the next stage the HPGR products were ground in a ball mill. The results showed that the grinding efficiency at higher values of operating pressure is greater, it was also observed a rapid increase in yield of the fine particle fractions, which can be directed to initial flotation operations. In the next stage, a methodological assumptions for optimization of a multi-stage comminution circuit were presented. In order to optimize the work effects of circuit the feed preparation manner for each stage of crushing should be taken into consideration. Another aspects which should not be missed are the crushing and grinding devices operating conditions (the relationship between the feed properties and the construction and operating parameters of the device) and characteristics of obtained products.
Źródło:
Rocznik Ochrona Środowiska; 2013, Tom 15, cz. 2; 1580-1593
1506-218X
Pojawia się w:
Rocznik Ochrona Środowiska
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Efficient chromium removal from aqueous solutions by precipitate flotation using rhamnolipid biosurfactants
Autorzy:
Shojaei, V.
Khoshdast, H.
Powiązania:
https://bibliotekanauki.pl/articles/110347.pdf
Data publikacji:
2018
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
kinetics
wastewater
chromium
rhamnolipid biosurfactant
precipitate flotation
Opis:
In the present research study, the efficient removal of hexavalent chromium from aqueous solutions by precipitate flotation method was investigated. The experiments were carried out with the use of ferrous sulfate as a precipitating agent for chromium and rhamnolipid bio surfactant (RL) as a precipitate collector. The effects of rhamnolipid and co-precipitate concentrations, aeration rate, solution pH, and salt addition on the chromium removal were studied using a full factorial design. The chromium removal and water recovery to foam products were analyzed as process responses. Statistical analyses showed that the effects of all factors on the chromium removal followed a non-linear trend with a peak at the middle level. After the process optimization, the maximum chromium removal of 96.75±0.3% was obtained at pH value of 8, RL/Cr ratio of 0.01, Fe/Cr ratio of 3, and aeration rate of 50 cm3/min. Addition of salt with different cationic and anionic groups negatively influenced the removal efficiency. Kinetic studies suggested that the process of chromium removal by the precipitate flotation followed the first-order process with a rate constant of about 0.018 sec-1. Given the good removal capacity and kinetics, rhamnolipid biosurfactants can be a promising environmental-friendly bio collector for the removal of chromium ions from aqueous solutions.
Źródło:
Physicochemical Problems of Mineral Processing; 2018, 54, 3; 1014-1025
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effects of monovalent and divalent ions in coal gasification brine on the froth entrainment and flotation kinetics of anthracite coal
Autorzy:
Zheng, Kaidi
Bu, Xiangning
Zhou, Shaoqi
Zhang, Jing
Shao, Huaizhi
Sha, Jie
Xie, Guangyuan
Powiązania:
https://bibliotekanauki.pl/articles/1845216.pdf
Data publikacji:
2020
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
coal gasification brine
salts ions
coal flotation
entrainment
flotation kinetics
DLVO theory
Opis:
Water plays a critical role in various stages of flotation, which brings a lot of pressure to the flotation processing plants resided in dry areas. In this regard, it will be of significance to explore the feasibility of using wastewater resources in mineral flotation. Coal gasification brine (CGB) that contains a high concentration of salts becomes the subject of interest of this study. In this study, a synthetic CGB solution, which was prepared by adding NaCl, MgCl2, and CaCl2 to ultrapure water based on the composition of salts in a real CGB, was used in the flotation of anthracite coal. The comparison results based on the first-order model showed that flotation in the presence of the synthetic CGB solution gave a higher flotation selectivity (SI =7.086) than that of flotation in ultrapure water (SI=3.545). Water recoveries and average bubble sizes in the froth showed that the addition of the three salt ions (Na+, Mg2+, and Ca2+) was conducive to diminishing the entrainment of gangue materials as a result of the reduction of water reporting to the froth. Additionally, the zeta potentials and induction time measurements indicated that only divalent ions of Ca2+ and Mg2+ significantly compressed the double electrical layer and enhanced the attachment between bubbles and coal particles according to DLVO theory, which was further confirmed by the calculation of interaction energy between coal and bubbles. The findings of the present work may promote the use of CGB as a potential water resource in coal flotation.
Źródło:
Physicochemical Problems of Mineral Processing; 2020, 56, 5; 960-974
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effects of frothers and particle size on the flotation kinetics of the Jameson Cell
Autorzy:
Şahbaz, Oktay
Demir, Muhammet Kubilay
Powiązania:
https://bibliotekanauki.pl/articles/1845223.pdf
Data publikacji:
2020
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
flotation kinetics
Jameson cell
frothers
particle size
Opis:
Determination of the flotation kinetic is crucial for optimization, simulation, and plant design for flotation processes. Even though there are many studies carried out to clarify the kinetic properties of the conventional flotation cells, there is not enough detailed study about the Jameson cell which is used more than 300 plants but no application in Turkey yet. One of the most important parameters affects the kinetic of flotation is a frother. The effects of common frothers on the kinetic of Jameson cell can be crucial due to the possible further application of the cell in European and Turkish flotation industries. The present study was performed out to reveal the kinetic properties of the Jameson cell by using both pure quartz and coal particles. Besides, the effects of three different types of frothers on the kinetic of the Jameson cell were investigated for various particles sizes. According to the results, aliphatic alcohol type frother (MIBC) provided higher recovery for fine particles, while polypropylene glycol type frother (AF65) gave a better ability to float medium and coarse size particles. Additionally, the results show that the Jameson cell was four times faster than the mechanical cell for medium size while the ratio was three times for coarse particles. Lastly AF65 can be used for flotation of coarse particles in the Jameson cell while MIBC can be preferred for fines.
Źródło:
Physicochemical Problems of Mineral Processing; 2020, 56, 5; 829-838
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł

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