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Suitability and characterization of pumice, bauxite, and ferrochrome slag as alternative raw materials in vitrified ceramic industry

Benkli Yunus Emre, Koca Kazım

Physicochemical Problems of Mineral Processing

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2024

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Vol. 60, iss. 2

art. no. 187967

EN

Since the natural raw materials used in the manufacture of clay-based ceramic products vary greatly in the sintering stage, the resulting products are quite heterogeneous. In addition, different types of waste could be used to make ceramic tiles and bricks. Therefore, this study aimed to investigate the effects of pumice, bauxite, and ferrochrome slag on the vitrified ceramic body. In this context, firstly, binary slip mixtures were prepared by composing 40% clay with 60% pumice, bauxite, and ferrochrome slag one by one, which was reduced to 150 μm in particle size. Then, the mixtures were shaped by slip casting method and sintered at 1000°C, 1100°C, 1200°C, and 1250°C. The qualitative XRD analysis was performed in order to see the phase variation, and physical properties were determined with shrinkage and water adsorption measurements. Since pumice transformed into a glassy phase after sintering at 1100°C, an amorphous phase was observed in all samples produced with pumice. In addition, the mullite development occurred in clay-pumice body composition with the temperature increment. However, tridymite and cristobalite phases were analysed in clay bauxite and ferrochrome body compositions. The shrinkage and water adsorption values, which were high in the samples sintered at 1000°C, began to reduce from 1100°C to 1250°C significantly. In particular, water adsorption reached 0% in the clay-pumice system which was suitable for a fully vitrified-high density standard (ISO13006-10545/98). Besides, the brighter colour was reached in the clay-pumice system while brown and black colour was seen in clay-bauxite and clay-ferrochrome bodies, respectively.

2

Flotation separation influenced by the rheological properties of diaspore-pyrite mixed pulp

Zhao Yongqing, Li Xianhai

Physicochemical Problems of Mineral Processing

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2023

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Vol. 59, iss. 6

art. no. 174305

EN

The effects of pyrite and diaspore with different particle sizes on the rheological properties of pulp with butyl xanthate added as a collector were studied, and the mechanism for rheological pyrite separation from diaspore by flotation was probed. The apparent viscosity of the diaspore pulp with different particle sizes was higher than that of pyrite, especially for -30 μm diaspore. Microfine diaspore was an important component affecting the apparent viscosity and yield stress of the diaspore-pyrite mixed pulp, and the pulp became a non-Newtonian fluid when the mass fraction of fine-grained diaspore in the mixed pulp was high. In this study, sodium hexametaphosphate (SHMP) was used to control the rheology of the mixed pulp and improve the pyrite flotation, and the S (sulfur) recovery rate first increased and then decreased with increasing SHMP concentration. The apparent viscosity of the pulp decreased by 3.01% and the S recovery rate increased by 34.83% when the amount of added SHMP was 0.05 mg/kg. The apparent viscosity with 0.50 mg/kg SHMP was 21.76% lower than that seen with the addition of 0.05 mg/kg SHMP, but the S recovery rate was also reduced by 14.94%. Further research showed that the increased SHMP concentration led to increases in the electronegativities of the particle surface and the repulsive force between particles, which prevented agglomeration of the particles, reduced the apparent viscosity and yield stress of the mixed pulp, promoted collisions between the pyrite particles and the bubbles, and reduced the resistance of the air bubbles to flotation.

3

The development and utilization of bauxite resources in the Guizhou Province and relevant challenges to the ecology and the environment

Chen Xiaofu, Li Xuexian, Wu Pan, Zha Xuefang, Liu Yabin, Wei Tao, Ran Wenrui

Gospodarka Surowcami Mineralnymi

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2022

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T. 38, z. 2

5--30

EN

The environmental problems caused by the development and utilization of mineral resources have become important factors affecting ecological security. Guizhou is a Chinese province with relatively developed paleoweathered sedimentary bauxite deposits, abundant resource reserves, and a long history of mining. And, the demand for bauxite in Guizhou is expected to continue to grow. However, long-term or unreasonable resource development has produced a series of prominent environmental problems, such as the occupation and destruction of land resources and heavy metal pollution in soil and water bodies. Based on the existing research results in China and abroad, this paper analyzes the current situation, distribution characteristics, and development and utilization of bauxite resources in Guizhou to explain the corresponding environmental impacts. The results show that because of the many types and high concentrations of associated elements in bauxite and the high alkalinity, heavy metal components, and radioactive elements in red mud, the development and utilization of bauxite resources are associated with higher environmental risk. And more impact of bauxite mining on regional biodiversity, soil, air, surface water, and groundwater need to be evaluated. This paper also proposes coping strategies or countermeasures of environmental governance and control to achieve the green, sustainable and high-quality development of bauxite-related industries for meeting future environmental requirements.

PL

Problemy środowiskowe spowodowane zagospodarowaniem i wykorzystaniem surowców mineralnych stały się ważnymi czynnikami wpływającymi na bezpieczeństwo ekologiczne. Guizhou to chińska prowincja ze względnie rozwiniętymi osadowymi złożami boksytu, bogatymi rezerwami surowców i długą historią wydobycia. Oczekuje się, że popyt na boksyt w Guizhou będzie nadal rósł. Jednak długoterminowy lub nieracjonalny rozwój wykorzystania zasobów spowodował szereg znaczących problemów środowiskowych, takich jak: zajmowanie i niszczenie zasobów ziemi oraz zanieczyszczenie metalami ciężkimi gleby i zbiorników wodnych. W oparciu o istniejące wyniki badań w Chinach i za granicą, w artykule dokonano analizy obecnej sytuacji, charakterystyki dystrybucji oraz rozwoju i wykorzystania zasobów boksytu w Guizhou, w celu wyjaśnienia odpowiedniego wpływu na środowisko. Wyniki pokazują, że ze względu na wiele rodzajów i wysoką koncentrację towarzyszących pierwiastków w boksycie oraz wysoką alkaliczność, składniki metali ciężkich i pierwiastki radioaktywne w czerwonym szlamie, rozwój i wykorzystanie zasobów boksytu wiążą się z wyższym ryzykiem dla środowiska. Ponadto należy ocenić większy wpływ wydobycia boksytu na regionalną bioróżnorodność, glebę, powietrze, wody powierzchniowe i gruntowe. Niniejsza praca proponuje również strategie radzenia sobie lub środki zaradcze zarządzania i kontroli środowiska w celu osiągnięcia ekologicznego, zrównoważonego i wysokiej jakości rozwoju przemysłu związanego z boksytem dla spełnienia przyszłych wymagań środowiskowych.

4

Effect and mechanism of surface pretreatment on desulfurization and desilication from low-grade high-sulfur bauxite using flotation

Zhou Jieqiang, Mei Guangjun, Yu Mingming, Li Haonan

Physicochemical Problems of Mineral Processing

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2019

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Vol. 55, iss. 4

940--950

EN

Surface pretreatment using a hot alkaline solution was carried out to improve the effect of desulfurization and desilication on low-grade bauxite with high sulfur content. The results demonstrated that, after surface pretreatment, a maximum grade and recovery of 66.17% and 87.27%, respectively, were achieved, and the sulfur content and ratio of A/S were 0.19% and 7.09, respectively. The surface pretreatment mechanism was further analysed by XRD and SEM analyses. The improved results of desulfurization and desilication were attributed to the selective corrosion of aluminosilicate minerals in coarse particles, reducing the active silicon sites on the surface of coarse particles as well as enhancing the cation exchange between the collector and aluminosilicate minerals.

5

Investigation and optimization of use of anionic collectors in direct flotation of bauxite ores

Liu C., Feng A., Guo Z.

Physicochemical Problems of Mineral Processing

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2016

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Vol. 52, iss. 2

932--942

EN

Bauxite is the main raw material for the alumina industry. Direct flotation is the most widely used method for bauxite beneficiation. In this study, a large number of direct flotation tests were carried out using several anionic reagents. The testing concluded that vegetable oil acid (VOA), naphthenic acid (NA) and lauryl polyoxyethylene phosphate (AEP12) were the three outstanding collectors for bauxite direct flotation. ZMC collector was mixed and prepared using VOA, NA and AEP12, in which the mass ratio of VOA, NA and AEP12 was 1:1:0.5. When processing the bauxite ores of the mass ratio of Al2O3 to SiO2 (A/S) = 4.99, the A/S of the final concentrate was 7.08 and the recovery of Al2O3 was 90.22%. When processing ores of A/S = 4.5, the A/S of the final concentrate was 7.04 and the recovery of Al2O3 was 92.16%. Thus, it can be seen that properties and behaviors of the ZMC reagent were remarkable and met the demands of the “Lime-Bayer Process”.

6

ANFIS based prediction of the aluminum extraction from boehmite bauxite in the Bayer process

Mihajlović I., Đurić I., Živković Ž.

Polish Journal of Chemical Technology

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2014

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Vol. 16, nr 1

103-109

EN

This paper presents the results of nonlinear statistical modeling of the bauxite leaching process, as part of Bayer technology for alumina production. Based on the data, collected during the year 2011 from the industrial production in the alumina factory Birač, Zvornik (Bosnia and Herzegovina), nonlinear statistical modeling of the industrial process was performed. The model was developed as an attempt to define the dependence of the Al2O3 degree of recovery as a function of input parameters of the leaching process: content of Al2O3, SiO2 and Fe2O3 in the bauxite, as well as content of Na2Ocaustic and Al2O3 in the starting sodium aluminate solution. As the statistical modeling tool, Adaptive Network Based Fuzzy Inference System (ANFIS) was used. The model, defined by the ANFIS methodology, expressed a high fitting level and accordingly can be used for the efficient prediction of the Al2O3 degree of recovery, as a function of the process inputs under the industrial conditions.

7

Metodyka określania parametrów odsłonięcia stropu w komorach wybierkowych przy eksploatacji złóż boksytu w warunkach głębokiego zalegania w północnej części Uralu

Sidorov D. V.

Mechanizacja i Automatyzacja Górnictwa

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2014

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R. 52, nr 2

51--57

PL

W artykule przedstawiono inżynieryjną metodykę określania szerokości odsłonięcia stropu w komorach wybierkowych. Metodyka uwzględnia zmiany procesów geomechanicznych w górotworze, wynikających ze skutków prac górniczych prowadzonych na poziomach głębokiego zalegania z pozostawieniem w zrobach filarów międzykomorowych (rudnych) i filarów granicznych oraz z uwzględnieniem wpływu konwergencji skał stropowych w systemie komorowo-filarowym.

EN

Refer engineering technique for determining the span of the roof treatment chambers. Method takes into account the change of geomechanical processes in the rocks of the roof due to the transition of mining operations in the deep horizons for technological schemes room-and-pillar system with leaving in the goaf of barrier pillars, as well as the influence of the joint convergence of roof rocks and compliant interchamber pillars.

8

Hydrometallurgical processing of egyptian bauxite

Amer A. M.

Physicochemical Problems of Mineral Processing

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2013

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Vol. 49, iss. 2

431--442

EN

A bauxite ore from Um Bogma, Southwestern Sinai, Egypt was mineralogically characterized. It contains 70% gibbsite, 13.2% quartz and 11.0% kaolinite. Beneficiation of the ore reduced the quartz content to 2.4%. Hydrometallurgical processing of the beneficiated gibbsitic bauxite was performed by hot leaching with sodium carbonate and lime in an attritor. Aluminium was converted to soluble sodium aluminate low in SiO2 (<0.1%) and the recovery was over 95% for a short leaching duration of 30 minutes at 90 °C. The residue was essentially composed of calcium silicate.

9

Characterization and applications of red mud from bauxite processing

Cablik V.

Gospodarka Surowcami Mineralnymi

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2007

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T. 23, z. 4

27-38

EN

This work describes the characterization of red mud – a waste generated by the Bayer process in the aluminium industry – which causes environmental problems. Residue of the alumina leaching from bauxite was analyzed for mineral compositions of the mineral ore and its residue for chemical composition, density, and grain-size composition. The residue was calcinated and finally tested as a pigment for use in the building material industry. The test blocks were tested on the compressive strength.

PL

W artykule przedstawiono charakterystykę czerwonego mułu – odpadów powstających w procesie produkcji aluminium metodą Bayera. Przeprowadzono analizę pozostałości po przeróbce boksytów w celu określenia ich składu mineralogicznego, określono również skład chemiczny, skład ziarnowy oraz gęstość produktu. Produkt został poddany kalcynacji, a następnie została zbadana jego przydatność jako czerwonego pigmentu dla barwienia wyrobów przemysłu budowlanego. Badaniu poddano kostki betonowe wytworzone z dodatkiem pigmentu, określając ich wytrzymałość po 7, 14, i 28 dniach w temperaturze pokojowej. Uzyskany pigment charakteryzuje się następującym składem chemicznym: Fe2O3 – 48,50%, SiO2 – 11,53% oraz Al2O3 – 14,14%. Średnia gęstość czerwonych mułów wynosiła 3,05 g/cm3. Straty prażenia 4,93% dla temperatury 900°C i 5% dla temperatury 950°C. Czerwone muły uzyskują kolor w wyniku procesu kalcynacji. Pigment charakteryzuje się drobnym uziarnieniem – zawartość klasy powyżej 0,147 mm – 4%. Pigment był dodawany do standardowego betonu (o składzie: kruszywo, cement i woda) w ilości od 1 do 32%.

10

Oznaczanie AI2O3 i Fe2O3 w boksytach

Stec K., Burdyl M.

Materiały Ceramiczne

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2006

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R. 58, nr 2

68-70

PL

Oznaczanie zawartości tlenku glinu i żelaza w boksytach nie można zaliczyć do rutynowych analiz chemicznych próbek wysokoglinowych. Proponowane metody miareczkowe w normach PN-85/H-04154 i PN-EN 995-2 nie gwarantują uzyskania powtarzalnych wyników oznaczania AI2O3 i Fe2O3. Autorzy przypuszczają, że jest to związane z formą występowania tlenku tytanu w boksytach. Dlatego autorzy pracy podjęli próbę opracowania metodyki pomiaru AI2O3 i Fe2O3 w boksytach gwarantującej powtarzalne wyniki.

EN

Determining chemical composition of bauxite specially AI2O3 and Fe2O3 is not a routine procedure. The titration method proposed in PN-85/H-04154 and PN-EN 995-2 does not guarantee repeatable results of AI2O3 and Fe2O3 determination. It is connected with high concentration of titanium in bauxite. That is why the authors started to develop the new methodology of the AI2O3 and Fe2O3 determination in bauxite which guaranteeing high reproducible and repeatable results.

11

Ocena jakości importowanych surowców wysokoglinowych - andaluzytu i boksytu w świetle badań petrograficznych

Kapuściński T., Probierz M.

Ceramika. Materiały Ogniotrwałe

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2000

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R. 52, nr 4

137-143

PL

Przedstawiono analizę petrograficzną importowanych dla potrzeb Przemysłu Materiałów Ogniotrwałych andaluzytu oraz kalcynowanego boksytu. Analizowany koncentrat andaluzytowy wykazuje zawartość AI2O3 (59,31%) przy ilości Fe2O3 (1,84%) i Ti02 (0,10%). Korzystne dla przebiegu procesu wypalenia i uzyskania zwartej struktury jest stwierdzone równomierne rozmieszczenie minerałów łyszczykowych odpowiedzialnych za powstanie fazy ciekłej. Niekorzystną cechą surowca jest występowanie w koncentracie przerostów andaluzytu z nieprzeobrażoną w niego substancję ilastą. Ziarna koncentratu andaluzytowego cechuje ponadto podatność na rozpad mechaniczny oraz skłonność do hydratacji i hydrolizy zawartych w nim minerałów łyszczykowych. Boksyt kalcynowany cechuje bardzo wysoka zawartość Al2O3 (92,26%). Wśród faz domieszkowych oznaczono minerały tytanowe (rutyl, spinel tytanowo-glinowy) oraz hematyt i mullit. Podobnie jak w przypadku andaluzytu ujawnia on mikroskopowo zróżnicowany stopień przeobrażenia termicznego w korund.

EN

A petrographic analysis of andalusite and calcinated bauxite, imported for refractory materials industry, is presented. Andalusite concentrate shows 59,31% of AI2O3 , 1,84% of Fe2O3 and 0,10% of TiO2. Micaceous minerals, responsible for fluid phase formation, show a uniform distribution which is beneficial for firing process and compact texture. A negative feature of the material is that there are andalusite bands and clay found in the concentrate. Moreover, andalusite concentrate grains are suscepetible to mechanical breakdown while the micaceous minerals have an inclination to undergo hydration and hydrolysis. A very high content of AI2O3 (92,26%) is found in calcinated bauxite. Titanium minerals (rutile, titanium-aluminum spinel), hematite and nullite have been determined among additional phases. Just like andalusite, the bauxite shows microscopically a differentiated degree of thermal transformation to corundum.