Informacja

Drogi użytkowniku, aplikacja do prawidłowego działania wymaga obsługi JavaScript. Proszę włącz obsługę JavaScript w Twojej przeglądarce.

Wyszukujesz frazę "SO2" wg kryterium: Wszystkie pola


Tytuł:
Zmniejszenie emisji cząstek stałych i SO2 przez transport morski
ABATEMENT OF SO2 AND PM EMISSIONS BY MARITIME TRANSPORT
Autorzy:
KRUPA, Andrzej
JAWOREK, Anatol
MARCHEWICZ, Andrzej
SOBCZYK, Arkadiusz T.
CZECH, Tadeusz
ANTES, Teresa
ŚLIWIŃSKI, Łukasz
KURZ, Mirosław
SZUDYGA, Michał
OTTAWA, Andrzej
Powiązania:
https://bibliotekanauki.pl/chapters/1965631.pdf
Data publikacji:
2016
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Opis:
W pracy dyskutowane są różne możliwości techniczne stosowane w celu spełnienia wymagań odnośnie dopuszczalnych poziomów emisji cząstek stałych i SO2 przez transport morski W szczególności omówiono metodę skruberowania elektrostatycznego jako techniki, która z dużą skutecznością pozwala na jednoczesne usunięcie ze spalin tlenków siarki (>98%) oraz cząstek submikronowych i nanocząstek (>90% ilościowo). W skruberze elektrostatycznym wykorzystuje się wzajemne oddziaływania elektrostatyczne pomiędzy przeciwnie naładowanymi cząstkami stałymi i naładowanymi kroplami wody. Skruber tego typu może być zasilany wodą morską, co znacznie obniża koszty jego eksploatacji.
Various possibilities of technical means used in order to meet the requirements for acceptable levels of emissions of PM and SO2 from shipping are discussed. The interest is in particular focused the method of electrostatic scrubbing as a technique, which allows with high efficiency the simultaneous removal sulfur oxides (> 98%) and nanoparticles and sub-micron particles (> 90% by volume) from the flue gas. This type of scrubber uses electrostatic interactions between oppositely charged solid particles and charged water droplets. The scrubber unit of this type can be supplied with sea water, which significantly reduces the cost of its operation.
Źródło:
Powietrze atmosferyczne. Jakość – zagrożenia – ochrona; 172-181
9788374939423
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Use of natural soda ash production process waste for SO2 removal
Autorzy:
Tunali, Y. I.
Ertunç, S.
Powiązania:
https://bibliotekanauki.pl/articles/207588.pdf
Data publikacji:
2017
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
removal SO2
desulfurization fule gas
lignite
Chem Cad 60
usuwanie SO2
odsiarczanie spalin
węgiel brunatny
Opis:
Results of ChemCad©6.0 simulation have been presented on usability of natural soda ash production process waste in order to remove SO2 from flue gas. Properties and concentrations of the solutions used in this study belong to the waste stream of Eti Soda Inc., and the flue gas compositions were acquired from an existing thermal power plant. SO2 and H2O feed rates and flue gas entrance temperature to the absorption tower were optimized through the response surface methodology (RSM) in order to attain highest SO2 removal yields. It has been found that SO2 removal remained at 33.83% when the waste composition was lower than 2 wt. % while 100% SO2 removal was reached as the waste composition was increased to 8 wt. %. This result clearly demonstrates that treatment of natural soda ash production process waste can be done safely and economically while serving as an SO2 removal agent at the same time.
Źródło:
Environment Protection Engineering; 2017, 43, 2; 69-80
0324-8828
Pojawia się w:
Environment Protection Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Reactivity of marble wastes for potential utilization in wet flue gas desulphurization
Autorzy:
Altun, N. E.
Powiązania:
https://bibliotekanauki.pl/articles/110132.pdf
Data publikacji:
2016
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
marble
reactivity
thermal power production
SO2
desulphurization
Opis:
Wastes of most marble types are distinguished with their superior CaCO3 content and potential to utilize them as an alternative to limestone. Control of SO2 using marble wastes in wet flue gas desulphurization (WFGD) units of coal fired thermal power plants is an important opportunity. In this study, nine types of marble wastes were evaluated in terms of their ability to dissolution (reactivity) in an acidic environment. The reactivity was expressed as fractional conversion with time with respect to the chemical composition and particle distribution of wastes as well as temperature and pH of solution. Dissolution reaction rate constants were also computed. Reactivity of the wastes varied significantly with chemical compositions of the marble types. The same marble type displayed different dissolution profiles as a function of test conditions (fineness, temperature, pH). Higher contents of CaCO3 and Fe2O3 positively influenced dissolution ability and rates, whereas increased MgCO3 content had adverse effects. The changes in particle size, temperature and pH influenced the reactivity. The reactivity increased with decreasing particle size. Also, higher temperature and increased acidity favored dissolution ability of the marble wastes. Our results showed that under optimized conditions marble wastes, having a higher content of CaCO3 and low content of MgCO3, are potential SO2 sorbent alternative.
Źródło:
Physicochemical Problems of Mineral Processing; 2016, 52, 1; 497-509
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Wpływ biomasy na stratę niedopału oraz emisję NOx i SO2
Autorzy:
Król, K.
Powiązania:
https://bibliotekanauki.pl/articles/1818114.pdf
Data publikacji:
2014
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
węgiel
biomasa
emisja NOx
emisja SO2
strata niedopału
współspalanie
Opis:
Przedmiotem pracy był proces współspalania zrębków drewna sosnowego z węglem kamiennym o średnicy ziaren pon. 200 μm. Celem naukowym pracy było poznanie mechanizmu oddziaływań biopaliw stałych na zachowanie się węgla w czasie współspalania. Badania pozwoliły poznać podstawowe mechanizmy rządzące współspalaniem biomasy z węglem oraz wyznaczyć parametry mające najbardziej znaczący wpływ na, emisję zanieczyszczeń i stratę niedopału. Cele szczegółowe pracy obejmowały zebranie informacji (dla węgla kamiennego i zrębków drewna sosnowego) o wpływie właściwości mieszaniny obu paliw na stopień wypalenia pyłu i emisję zanieczyszczeń gazowych (NOx i SO2). W pracy zgromadzono nowe dane charakteryzujące przydatność technologiczną biopaliw stałych. Znajomość powyższych właściwości ma kluczowe znaczenie dla projektowania urządzeń kotłowych, przygotowania paliwa, jak również ma znaczenie dla oceny warunków eksploatacji kotłów spalających węgiel i biomasę.
Źródło:
Zeszyty Energetyczne; 2014, 1; 101--112
2658-0799
Pojawia się w:
Zeszyty Energetyczne
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Study on seawater scrubbing for SO2 removal from ships power plant exhaust gas
Autorzy:
Ma, Yiping
Xu, Leping
Su, Penghao
Feng, Daolun
Yang, Kailiang
Powiązania:
https://bibliotekanauki.pl/articles/207540.pdf
Data publikacji:
2020
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
sulfur dioxide
absorption
seawater
dwutlenek siarki
adsorpcja
woda morska
Opis:
The mechanism of SO2 absorption in seawater is investigated, and the experiment was carried out accordingly. Emphasis is on applications of seawater scrubbing of ship’s power plant exhaust gas containing SO2. The formulated model is used to predict the influence of various parameters on both pH of tailwater and seawater desulfurization capability, e.g., the partial pressure of SO2, the partial pressure of CO2, tailwater temperature, pH and alkalinity of seawater. Experiment results indicated that the seawater desulfurization capacity increases with both increasing partial pressure of SO2, pH and alkalinity and decreasing partial pressure of CO2 and temperature. The study shows the desulfurization capacity of seawater with 3.5% salinity is approximately twice that of freshwater. Different scenarios in which the required absorbent supply rate for a given SO2 removal efficiency are studied. It is observed a 97% removal efficiency, corresponding to meeting the SOx limits in the SOx emission control areas (SECA) while operating on a heavy fuel oil containing sulfur 3.5 wt. %, requires a minimum water supply rate of 0.0407–0.0683 m3/kWh, depending mainly on the water composition in terms of alkalinity and salinity. Such data are important in assessing the operation cost of the water scrubbing system.
Źródło:
Environment Protection Engineering; 2020, 46, 1; 31-47
0324-8828
Pojawia się w:
Environment Protection Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Experimental investigation of seawater scrubbing of SO2 in turbulent contact absorbers and spray absorbers
Autorzy:
Ma, Yiping
Xu, Leping
Zhou, Junfeng
Yang, Kailiang
Li, Guoxiang
Powiązania:
https://bibliotekanauki.pl/articles/208062.pdf
Data publikacji:
2019
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
seawater
marine engine
maritime shipping
woda morska
silnik okrętowy
żegluga morska
Opis:
The SOx emissions of the marine engine are regulated by international maritime conventions. In this paper, the effect of various parameters, including SO2 partial pressure, liquid to gas ratio (L/G), alkalinity and pH, was investigated by seawater scrubbing experiment in a turbulent contact absorber (TCA) and a spray absorber (SA) on a laboratory scale. The experimental data showed that the desulfurization efficiency of TCA was mainly dependent on the value of L/G and irrelevant to the changing way of L/G; the appropriate L/G of TCA was 2.3 dm3/m3 and pH of effluent water was 2.4–2.8 at the L/G of 1.1–2.8 dm3/m3. Comparatively, the desulfurization efficiency of increasing liquid flow rate was better than that of decreasing gas flow rate in the SA experiment. At the gas velocity of 1.58 m/s and L/G of 2.3 dm3/m3, the desulfurization efficiencies and drop pressures of TCA and SA were 75.9% and 42.4%, 690 and 260 Pa, respectively. The results indicate that TCA chosen as an absorber is likely to be a competitive desulfurization technique for controlling marine diesel emission.
Źródło:
Environment Protection Engineering; 2019, 45, 3; 39-53
0324-8828
Pojawia się w:
Environment Protection Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Napromieniowanie spalin wiązką elektronów z akceleratora dla jednoczesnej redukcji emisji SO2, NOX i WWA z kotłów opalanych węglem
ELECTRON BEAM TECHNOLOGY FOR SIMULTANEOUS SO2, NOx AND PAHs EMISSIONS CONTROL FROM COAL-FIRED BOILER
Autorzy:
LICKI, Janusz
CHMIELEWSKI, Andrzej G.
ZIMEK, Zbigniew
Powiązania:
https://bibliotekanauki.pl/chapters/1965510.pdf
Data publikacji:
2016
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Opis:
W pracy przedstawiono aktualny stan technologii napromieniowania spalin wiązką elektronów z akceleratora dla oczyszczania spalin emitowanych z kotła opalanego pyłem węglowym. Badania podstawowe tej technologii przeprowadzono na instalacji pilotowej zlokalizowanej w Elektrociepłowni Kawęczyn, w której oczyszczano spaliny emitowane z kotła WP-120. Technologia ta zapewnia jednoczesne usunięcie wielu zanieczyszczeń gazowych. Usunięcie NOx jest procesem radiacyjnym. Jego efektywność usunięcia silnie zależy od dawki zaabsorbowanej w spalinach, temperatury napromieniowywanych spalin i stężenia wlotowego NOx. Usunięcie SO2 jest złożeniem dwóch procesów: radiacyjnego i termicznego procesu bezpośredniej reakcji SO2 z amoniakiem dozowanym do spalin. Efektywność usunięcia SO2 silnie zależy od stechiometrii amoniaku, temperatury i wilgotności spalin oraz dawki. Zaobserwowano synergetyczny wpływ wysokich stężeń SO2 na usunięcie NOx. Usunięcie WWA jest procesem radiacyjnym a ich efektywność usunięcia silnie zależy od dawki napromieniowania, wilgotności spalin i stechiometrii amoniaku. Głównymi zaletami technologii napromieniowania spalin są jednoczesna redukcja stężeń wielu zanieczyszczeń (SO2, NOx i WWA), a proces jest suchy, bezodpadowy i łatwo sterowalny (tylko trzy parametry muszą być sterowane).
The paper presents the current issues of the electron beam technology for purification of flue gas from coal-fired boiler. It is a dry scrubbing process ensuring the simultaneous removal of SO2, NOx and PAHs with high removal efficiency in one step with generation of usable byproduct.
Źródło:
Powietrze atmosferyczne. Jakość – zagrożenia – ochrona; 212-222
9788374939423
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Simultaneous removal of NOx, SO2, CO and Hg from flue gas by ozonation. Pilot plant studies
Autorzy:
Głomba, M.
Kordylewski, W.
Powiązania:
https://bibliotekanauki.pl/articles/950039.pdf
Data publikacji:
2014
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
carbon dioxide
flue gases
ozone
ozonization
pilot plants
sulfur dioxide
gas absorption
NOx removal
So2 removal
CO removal
dwutlenek węgla
tlenki azotu
spaliny
ozon
ozonowanie
instalacje pilotażowe
dwutlenek siarki
absorpcja gazu
usuwanie NOx
usuwanie SO2
usuwanie CO
Opis:
The results of pilot plant investigations of simultaneous removal of NOx, SO2 and Hg from flue gas with ozone as the oxidizing agent and the spray tower absorber with NaOH solution as the absorbent have been presented. Flue gas was delivered into the pilot plant at the flow rate of 200 m3/h from the coal fired OP-430 boiler. The effectiveness of NOx removal was over 95% when the molar ratio O3/NO reached 2.0. Sulfur dioxide was practically completely washed out from flue gas in the absorber at the liquid-to-gas ratio 7.5 dm3/m3. The effectiveness of Hg removal in the studied system was approximately 80%. It was pointed out that CO concentration in flue gas could considerably increase the ozone consumption. The effect of carbon dioxide in flue gas on the chemistry of absorption due to hydroxides conversion into carbonates and bicarbonates was noticed.
Źródło:
Environment Protection Engineering; 2014, 40, 3; 113-125
0324-8828
Pojawia się w:
Environment Protection Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effects of $Ca{2+}$ and $SO_4^{2-}$ ions on fluorite flotation
Autorzy:
Xun, Luobing
Hu, Jiacheng
Shi, Qing
Zhang, Guofan
Powiązania:
https://bibliotekanauki.pl/articles/1448205.pdf
Data publikacji:
2021
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
fluorite
flotation
calcium cation
sulphate anion
Opis:
The effects of $Ca^{2+}$ and $SO_4^{2-}$ on the flotation behaviour of fluorite with sodium oleate as a collector and the underlying mechanism by which these effects were investigated via micro-flotation experiments, solution chemistry calculations, and X-ray photoelectron spectroscopy. The results indicated that the addition of $SO_4^{2-}$ and $Ca^{2+}$ inhibited fluorite flotation and the inhibition effect was increased by the addition of pH. This was mainly due to the increase of the sulphate-containing components in the solution and the adsorption of $SO_4^{2-}$ on the surface of fluorite. With the increase of pH, the alkalinity of the solution increases, OH- and more $SO_4^{2-}$ are further adsorbed on the fluorite surface, thereby reducing the recovery of fluorite flotation.
Źródło:
Physicochemical Problems of Mineral Processing; 2021, 57, 2; 95-104
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Enhancing SO2 removal efficiency by lime modified with sewage sludge in a novel integrated desulfurization process
Autorzy:
Qin, L.
Han, J.
Chen, W.
Liu, Z.
He, M.
Xing, F.
Powiązania:
https://bibliotekanauki.pl/articles/950037.pdf
Data publikacji:
2017
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
sewage sludge
steel industry
sintering process
osad ściekowy
przemysł hutniczy
proces spiekania
Opis:
In China, the sintering process annually emitted around 1.5 million t SO2, representing 70% of SO2 produced from the iron and steel industry. Lime based sorbent was modified with municipal sewage sludge (MSS) and the influence of the modification on the desulfurization efficiency was investigated in a laboratory-scale novel integrated desulfurization (NID) reactor. The properties of modified sorbent were characterized by the Brunauer–Emmett–Teller (BET) analyzer and X-ray fluorescence (XRD) analyzer. BET surface area was increased from 17.48 to 46.68 m2g–1. when the MSS/lime ratio increased from 0 to 0.08. Ca4Al8Si8O32, Ca1.5SiO3.5, Na2Si2O5 and CaSiO3 found in the modified lime benefited for the increase of the BET surface area and pore volume. The effects of sewage sludge/CaO weight ratio, calcination temperature and hydration time on the desulfurization efficiency were also studied. SO2 removal efficiency was increased from 88.7% to 97.3% after using the lime modified with sewage sludge.
Źródło:
Environment Protection Engineering; 2017, 43, 4; 17-27
0324-8828
Pojawia się w:
Environment Protection Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Research on products of simultaneous removal of SO2 and NOx from flue gas by ozonation and alkaline absorption
Autorzy:
Głomba, M.
Hałat, A.
Kordylewski, W.
Łuszkiewicz, D.
Powiązania:
https://bibliotekanauki.pl/articles/206900.pdf
Data publikacji:
2016
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
soda kaustyczna
instalacja kogeneracyjna
spaliny
związki azotu
ozonowanie
instalacje pilotażowe
dwutlenek siarki
caustic soda
cogeneration plants
exhaust gases
flue gases
nitrogen compounds
ozonization
pilot plants
sulfur dioxide
Opis:
The results of laboratory scale research have been presented on the effects of ozonation of carrier gas containing NOx and SO2 on by-products trapped in Dreschel washers with solution of sodium hydroxide. The controlling parameter in this process was the ozonation intensity determined by the molar ratio O3/NOx. The measured by-products in a scrubber were SO32- , SO42- , NO2- and NO3- ions. It has been shown that ozonation of flue gas favours oidation of nitrites to nitrates and sulfites to sulfates in alkaline solution. Some of these results were confirmed in a pilot scale studies. Pilot plant was located in Wroclaw CHP (Combined Heat and Power), which provided flue gas for testing at a rate of 200 m3/h from the OP-430 boiler. Exhaust gases were ozonized and captured simultaneously with SO2. Sodium hydroxide was used in a pilot scale as an absorbent.
Źródło:
Environment Protection Engineering; 2016, 42, 2; 125-136
0324-8828
Pojawia się w:
Environment Protection Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Simultaneous removal of SO2 and NOx from sintering flue gas using ammonia-Fe(II)EDTA combined with electrolytic regeneration
Autorzy:
Liang, Y.
Yao, X.
Quin, L.
Chen, W.
Han, J.
Powiązania:
https://bibliotekanauki.pl/articles/208117.pdf
Data publikacji:
2018
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
ammonia
desulfurization
flue gases
nitrogen oxides
nitrogen removal
sintering sulfur dioxide
amoniak
odsiarczanie
gazy odlotowe
tlenki azotu
usuwanie azotu
spiekanie
ditlenek siarki
Opis:
Sulfur dioxide and nitrogen oxide are health hazardous gases, which contribute to the formation of submicron acidic particulates. To reduce SO2 and NOx emission from the sintering flue gas, the combination of ammonia-Fe(II)EDTA solution scrubbing with Fe(III) electrolytic regeneration is proposed. The above method has the following advantages: direct conversion of NOx and SO2 to harmless N2 and SO4 2−, recovery of the by-product (NH4)2SO4), simultaneous removal of NOx and SO2 emission from flue gas in the reactor. The effect of the pH, initial Fe(II)EDTA concentration, and voltage on the desulfurization and denitration efficiencies was investigated using a bench-scale reactor. The maximal desulfurization and denitration efficiencies were 98% and 52%, respectively. The optimum parameters were pH ˃ 5.0, 2.1 V, and 0.05 mol·dm–3 Fe(II)EDTA concentration. SO2 and NOx removal from the sintering flue gas by ammonia-Fe(II)EDTA solution scrubbing combined with electrolytic regeneration was also demonstrated in a pilot-scale reactor.
Źródło:
Environment Protection Engineering; 2018, 44, 2; 19-36
0324-8828
Pojawia się w:
Environment Protection Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Leaching of manganese ores using corncob as reductant in H2SO4 solution
Autorzy:
Ali, S.
Iqbal, Y.
Farooq, U.
Ahmad, S.
Powiązania:
https://bibliotekanauki.pl/articles/110165.pdf
Data publikacji:
2016
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
siliceous manganese ore
characterization
leaching
corncob
H2SO4
Opis:
In this study, corncob was used as reductant for sulfuric acid leaching of manganese ore from Daweezi, Upper Mohmand Agency, Pakistan. X-ray diffraction of representative powdered samples revealed the presence of manganese silicate MnSiO(SiO4), calcite (CaCO3), and -quartz (SiO2). X-ray diffraction and energy dispersive spectroscopy analyses indicated that the examined manganese ore was siliceous in nature. Three process parameters were investigated in the present study including the particle size of the ore, leaching temperature, and amount of corncob. Manganese extraction of 92.48 wt% was achieved for a leaching time of 60 min at 90 oC using 1.9 mol/dm3 H2SO4 concentration and 4 g of corncob. The present results demonstrated that corncob is a low cost, renewable, and non-hazardous reducing agent for manganese leaching under mild acid conditions in comparison to the other available reagents.
Źródło:
Physicochemical Problems of Mineral Processing; 2016, 52, 1; 56-65
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
On the use of $Na_2SO_3$ as a pyrite depressant in saline systems and the presence of kaolinite
Autorzy:
Arancibia-Bravo, María P.
Lucay, Freddy A.
Sepúlveda, Felipe D.
Cisternas, Luis A.
Powiązania:
https://bibliotekanauki.pl/articles/1446523.pdf
Data publikacji:
2021
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
Na2SO3
IPETC
clays
flotation
saline solution
artificial neural networks
Opis:
The effect of Na2SO3 as a pyrite depressant in NaCl and KCl saline media and the presence of kaolinite were evaluated by zeta potential tests. Chalcopyrite was also included in the study, because pyrite usually accompanies this mineral. Subsequently, the floatability results of both minerals in the NaCl solution were optimized based on the design of experiments (DoE). The Box–Behnken DoE was applied considering the percentage of kaolinite $(X_1)$, collector dose $(X_2)$, and depressant dose $(X_3)$ as factors. The results were modeled using artificial neural networks (ANNs) to construct contour plots and to determine the optimal conditions. In particular, maximization of the mass recovery of chalcopyrite and minimization of that of pyrite were sought. The particle swarm optimization algorithm was used as an optimization technique. The results indicated that the optimal conditions to maximize the floatability of chalcopyrite were kaolinite 6.85%, collector dose $3.58 × 10^{–3} mol$ / $dm^3$, and depressant dose $3.49 × 10^{–5} mol$ / $dm^3$. On the contrary, the optimal conditions to minimize the floatability of pyrite were 5% kaolinite, collector dose $5 × 10^{–4} mol$ / $dm^3$, and depressant dose $6.4 × 10^{–5} mol$ / $dm^3$. Under these conditions, the mass recoveries of chalcopyrite and pyrite were 66.1% and 14.0%, respectively. The results also indicated that the presence of kaolinite negatively affects the flotation of chalcopyrite, while the effect of $Na_2SO_3$ is not significant. In general, the findings suggest that $Na_2SO_3$ is a viable alternative to consider as a pyrite depressant in saline environments.
Źródło:
Physicochemical Problems of Mineral Processing; 2021, 57, 4; 168-179
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The influence of activity coefficient and equilibrium constant models on the speciation of aqueous solutions of H2SO4–MgSO4–Al2(SO4)3 at 235 and 250 °C
Autorzy:
Dickson, Okechukwu Vincent
Deleau, Thomas
Coquelet, Christophe
Espitalier, Fabienne
Lombart, Julien
Tardy, Antoine
Powiązania:
https://bibliotekanauki.pl/articles/24085644.pdf
Data publikacji:
2023
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
activity coefficient
equilibrium constant
hydrometallurgy
speciation
thermodynamics
Opis:
Supersaturation occurs in many industrial applications promoting reactive crystallisation between the reactants to form solutes. These solutes accumulate during precipitation, leading to the formation of scales on the inner walls of the reactor and particularly around the stirrer, causing modifications in the hydrodynamics. This encrustation is responsible for process shutdowns in continuous crystallisation processes. Supersaturation control is essential for industrial processes aimed at controlling or inhibiting the formation of these solids. Knowledge of mineral solubility and chemical speciation is required to account for the composition of the complexes in the system in their various solid or aqueous forms. This speciation is obtained by considering the thermodynamic equilibrium constants of the dissociation/complexation reactions involved in the system, the pressure, and the activity coefficients of the chemical species in their molecular or electrolyte form. From these thermodynamic quantities and the state of the system, we can predict the direction of the reaction. This study highlights the risk of the lack of experimental information on equilibrium constants at high temperatures and moderate pressures. Our goal is to evaluate the accuracy of existing models classically used to predict the equilibrium constant in such very hard conditions encountered in hydrometallurgical processes. Furthermore, we demonstrate the influences of equilibrium constants estimation and activity coefficient models on the speciation of H2SO4–Al2(SO4)3–MgSO4 systems, forming hydronium alunite and kieserite in the laterite liquor of hydrometallurgical processes.
Źródło:
Physicochemical Problems of Mineral Processing; 2023, 59, 5; art. no. 167497
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł

Ta witryna wykorzystuje pliki cookies do przechowywania informacji na Twoim komputerze. Pliki cookies stosujemy w celu świadczenia usług na najwyższym poziomie, w tym w sposób dostosowany do indywidualnych potrzeb. Korzystanie z witryny bez zmiany ustawień dotyczących cookies oznacza, że będą one zamieszczane w Twoim komputerze. W każdym momencie możesz dokonać zmiany ustawień dotyczących cookies