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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:
From waste to treat waste : exploitation of marble dust as a harmful pollutant to a green adsorbent for dyes and heavy metals from industrial wastewater
Autorzy:
Attia, H.A.
Farghaly, Mohamed G.
Saleh, A.M.
Abdel Khalek, M.A.
Powiązania:
https://bibliotekanauki.pl/articles/2175448.pdf
Data publikacji:
2022
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
marble dust
pollutant
adsorbent
dye
heavy metals
textile wastewater
Opis:
The marble dust as a harmful industrial waste of marble fabrication was evaluated as aneconomical and efficient green adsorbent for Acid Red-1 dye and lead ions. The XRD, XRF, particle size, surface area and zeta-potential measurements were used to characterize the marble dust. The removal efficiency was optimized by studying several parameters such as pH, temperature, contact time, adsorbent dose and initial concentration. The optimum removal was achieved at pH 6, 20°C after 60 min in the presence of 2.5g/L marble dust. The rates of adsorption were found to follow the pseudo-second-order model. The results showed better fitting to Freundlich isotherm. The thermodynamic studies revealed that the adsorption process is spontaneous, exothermic and favorable at low temperature. The free energy (∆G°), enthalpy (∆H°), and entropy (∆S°) changes were calculated to predict the nature of adsorption.The removal efficiency was improved by calcination of the marble at 700°C. Application for textilewastewater showed high removal efficiency up to 99.9%of inorganic and organic pollutants. The product of treatment was used in the concrete and bricks manufactured, so there is nogeneration of second-order pollutants.
Źródło:
Physicochemical Problems of Mineral Processing; 2022, 58, 6; art. no. 154007
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The study of the characteristics of sand concrete based on marble waste sand
Autorzy:
Bebhalilou, Mohamed Ichem
Belachia, Mouloud
Houari, Hacene
Abdelouahed, Assia
Powiązania:
https://bibliotekanauki.pl/articles/396631.pdf
Data publikacji:
2020
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
sand concrete
waste
marble
substitution
durability
performance
beton piaskowy
odpady
marmur
substytut
trwałość
Opis:
The present study aims to valorize the waste and in particular the waste from the Fil-fila quarry. The main reason for choosing the waste from this quarry was the need to reduce the impact on the environment (by reducing stockpiling) and the raw material cost (economic reason). This study therefore consists in recovering this type of waste (discarded powder subject to weather changes) as sand in partial replacement of dune sand in the formulation of sand concrete with percentages of 5, 10, 15 and 20 %, by studying the behavior of these concretes in the fresh state (workability, density and occluded air) and the properties in the hardened state (compressive and tensile strength by bending, absorption by immersion, shrinkage and weight loss, chemical effect of HCl and H2SO4 solutions), and subsequently comparing the results obtained with reference samples (0%) based on ordinary sand. Based on the obtained results, it can be concluded that the substitution of ordinary (dune) sand with marble waste sand provides acceptable results from the point of view of workability, strength and durability. These observations are likely to widen the field of applications of these sand concretes based on marble waste.
Źródło:
Civil and Environmental Engineering Reports; 2020, 30, 1; 130-144
2080-5187
2450-8594
Pojawia się w:
Civil and Environmental Engineering Reports
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
IDENTYFIKACJA MARMURU UŻYTEGO W SARKOFAGU WŁADYSŁAWA JAGIEŁŁY W KATEDRZE WAWELSKIEJ
ORIGIN OF THE MARBLE OF THE TOMB OF KING JAGIELLO IN THE WAWEL CATHEDRAL IN KRAKOW
Autorzy:
Bromowicz, Jan
Magiera, Janusz
Powiązania:
https://bibliotekanauki.pl/articles/537890.pdf
Data publikacji:
2006
Wydawca:
Narodowy Instytut Dziedzictwa
Tematy:
TOMB OF KING JAGIELLO (MARBLE ANALYSIS)
WAWEL CATHEDRAL
Opis:
In an attempt to identify the marble of the tomb of King Jagiello, three kinds of marbles were used as a refernce material, i.e.: Italian Ammonitico Rosso, Austrian Roter Knollenkalk and Hungarian red. Structure, texture and mineral composition were examined and SEM-EDAX analysis was done. Very limited size of the sample available disabled the use of the optical microscope. Generally, the tomb is made of red limestone with a nodular structure and sound, non porous texture. The nodules are 1 to 5 cm in diameter. This kind of a decorative limestone being succeptible to carving and polishing is traditionally called a 'marble'. Four varieties were identified in the tomb: Variety 1. Colour is red-brownish, nodules are slightly lighter than a matrix. Indistinct parallel bedding, stylolites and ammonites can also be seen. Variety 2. Generally, red-brownish in colouring, with stronger contrast between nodules (yellow-pinkish) and matrix (brown-reddish). Variety 3. Dark red-brownish. Nodules do not contrast strongly from the matrix. Variety 4. Colour is intermediate between varieties 1 and 2. Structure, texture and colour point to the Ammonitico Rosso marble as a stone applied in the tomb. Size, shape and colour of the nodules as well as colouring of the matrix make it similar to a variety that occurs in the vicinity of Verona and is called Rosso di Verona. Hungarian marbles obviously differ from that used in the tomb. Their colouring is generally darker and more brownish. Nodules are less pronounced and less contrasted from the matrix. SEM and SEM-EDAX analyses did not appear particularly diagnostic. The sample from the tomb was generally more fine grained than the reference samples thus disabling comparison of further structural and textural features. However, similarities were detected between the tomb marble and the Rosso di Verona marble, e.g. in the texture and number of genarations of the micrite, presence of clay minerals and iron oxides. Noticeable is a presence of Al, Si and K in the tomb marble, being apparently connected with clay minerals and with products of chemical weathering. All this point to the Rosso di Verona as the most probable stone applied in the tomb. Chemical composition of the marbles form the Verona area is following: Si - 5.90% CaO - 51.31% MgO - 0.14% CO2 - 40.48% Fe2O3 - 0.66 % FeO - traces Al2O3 - 0.84% Mn - traces Average porosity is less than 0.5%, and water sorption is less than 0.1% (W. D. Grimm, R. Snethlage, 1984).
Źródło:
Ochrona Zabytków; 2006, 3; 87-96
0029-8247
Pojawia się w:
Ochrona Zabytków
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Petrographic study of selected sculptural works of Jan Michałowicz from Urzędów
Autorzy:
Ciosmak, Małgorzata
Rzęsa, Patrycja
Powiązania:
https://bibliotekanauki.pl/articles/390071.pdf
Data publikacji:
2018
Wydawca:
Politechnika Lubelska. Wydawnictwo Politechniki Lubelskiej
Tematy:
renaissance
Michałowicz
stone
sculpture
architecture
tombstone
petrography
analysis
rock
marble
alabaster
limestone
Opis:
Nowadays, in order to determine whether given rock properties make it useful for specifi c purposes, the material is examined using relevant test equipment. At the times of Jan Michałowicz, any knowledge in this respect was transmitted by the master to his apprentices, based on the master’s experience. The artist used domestic rock raw materials to sculpt monuments commemorating important persons who were his contemporaries. For the petrographic analysis, the authors selected the most distinguishable works of the artist, which he signed or which are most likely to have been sculpted by him. The authors analysed the materials used by the artist to carve specifi c elements of his works, as well as rock raw materials in terms of their historical and contemporary properties. Consequently, the petrographic study allowed to describe the rocks in greater detail, as well as their properties useful for sculpture purposes, and their durability. Artistic qualities helped determine the sources of stones used by Jan Michałowicz during his projects. These include the quarries near Pińczów (limestone), Kunów (sandstone), Bolechowice (marble), Żurawno (alabaster) and initially quarries in Hungary. The discussed works of Jan Michałowicz provide firm grounds for acknowledging the artist as the leading co-founder to Polish Renaissance art.
Źródło:
Budownictwo i Architektura; 2018, 17, 3; 201-218
1899-0665
Pojawia się w:
Budownictwo i Architektura
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
USING EDUCATIONAL MARBLE GAMES IN GERMAN LANGUAGE TEACHING
Autorzy:
COŞKUN, HASAN
Powiązania:
https://bibliotekanauki.pl/articles/628440.pdf
Data publikacji:
2015
Wydawca:
Fundacja Pro Scientia Publica
Tematy:
kitchen appliances, teaching German as a foreign language, educational marble game, exercise types, implementation
Opis:
The aim of this article is to show how German students can be motivated by learning games. Apart from the development and didacticisation of the learning game “Marbles”, the attitude of  Turkish families and language teaching educational establishments and the support of the DaF lessons by German mediating institutions in Turkey will be considered. The attitude of Turkish families to learning foreign languages is mostly positive. Turkish educational authorities and those responsible for education take various measures to expand foreign language teaching availability in the schools. German institutions which provide teachers (Goethe-Institut, ZfA, DAAD) promote the improvement of German teaching in Turkey. Nevertheless, the quality of German teaching is not satisfactory mostly because the available teachers are not adequately qualified, teacher training is remote from practice, the quality of text books and teaching materials, the traditions of learning, the excessively large classes, inadequate learning environment (language cabinets and equipment), the nature and method of central examinations (multiple choice) and their significance in the Turkish educational system. In the long-term, this leads to frustration in both teachers and students. The Turkish educational authorities initially took measures to expand the availability of language teaching in the course of harmonisation of the Turkish educational system to that of the EU e.g. the introduction of a second foreign language. German mediating institutions ensure reasonable further training for teachers locally and in Germany and support the creation of teaching materials etc. The Ministry of Education in Turkey, has started to take measures for students to learn other languages such as German, French, Russian, Spanish, Japanese, Italian, Arabic, ethnic languages in Turkey, et cetera in the educational institutions in addition to English. For example, in the Anatolian high schools two foreign languages are taught.  The Board for Higher Education in Turkey, has introduced second foreign language lessons in  foreign language teacher programs, envisioned to be taken for three semesters, in order for the language teachers to gain experience in the field of two languages.  Private education institutes are emphasizing that they are teaching more than one foreign language in order to draw more students. Families make an economic sacrifice for their children in order for them to learn foreign languages. It is observed that in some districts of certain major cities, teaching of foreign languages has started to be given as early as at kindergarten level. In Turkey, German is preferred as the second foreign language in general. Nowadays, German is the second preferred language from primary to high school in Turkey. The quality of German language lessons should be increased for more students to select German as the second foreign language in the coming years. Despite all these efforts, teaching foreign language is not up to the desired level in Turkey (Bayraktaroğlu, 2014, pp. 9-14; Demircan, 2014, pp. 17-22). For that reason, it is important that motivating teaching methods and teaching materials be developed for German teaching.
Źródło:
Journal of Education Culture and Society; 2015, 6, 1; 167-184
2081-1640
Pojawia się w:
Journal of Education Culture and Society
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The Evaluation Potential as Micronized Calcite of White Marble Waste
Ocena potencjału pozyskania zmikronizowanego kalcytu z odpadów z białego marmuru
Autorzy:
Deniz, Vedat
Polat, Ercan
Powiązania:
https://bibliotekanauki.pl/articles/318935.pdf
Data publikacji:
2020
Wydawca:
Polskie Towarzystwo Przeróbki Kopalin
Tematy:
calcite
marble wastes
micronized calcite
physical properties of micronized calcite
chemical properties of micronized calcite
physicochemical properties of micronized calcite
mineralogical properties of micronized calcite
kalcyt
odpady marmuru
kalcyt mikronizowany
właściwości fizyczne mikronizowanego kalcytu
właściwości chemiczne mikronizowanego kalcytu
właściwości fizykochemiczne mikronizowanego kalcytu
właściwości mineralogiczne mikronizowanego kalcytu
Opis:
Natural calcium carbonates have a great importance in the world’s economy due to their numerous applications areas such as calcium carbonate in the paper and paint industries. The final calcite products have rigorous quality specifications which are currently difficult to meet for local producers in Turkey. Therefore, large quantities of high white marble wastes have been transported long distances inside the country to supply the different industrial plants for using calcite. Marble wastes, located in Afyon and Kutahya regions, Turkey’s mid-west, are used generally for concrete and highway purposes. Evaluations of marble wastes are very important for the economic development of any country or region. This study aims at developing new perspective for evaluation of marble wastes as domestic calcite resources and serves as a guide for investment and decision making for the Turkey calcite industry. This paper presents applied research work to determining the product quality for evaluation as micronized calcite of marble wastes and gives an overview of the market situation for the regional producers. The aim of the work is to characterize four different marble wastes and to determine the potential for production of the required quality for the Turkey calcite market;- to control the quality of the products by application tests, including the measurement some tests.
Naturalne węglany wapnia mają ogromne znaczenie w światowej gospodarce ze względu na ich liczne zastosowania, takie jak węglan wapnia w przemyśle papierniczym i malarskim. Produkty handlowe kalcytu muszą spełniać rygorystyczne wymagania jakościowe, które obecnie są trudne do osiągnięcia przez lokalnych producentów w Turcji. Dlatego duże ilości odpadów z przeróbki białego marmuru zostały przetransportowane do zakładów przemysłowych które wykorzystują kalcyt. Odpady marmurowe, znajdujące się w regionach Afyon i Kutahya, w środkowo-zachodniej Turcji, są ogólnie wykorzystywane do betonu i budowy autostrad. Możliwość wykorzystania odpadów marmurowych jest bardzo ważna dla rozwoju gospodarczego każdego kraju lub regionu. W artykule przedstawiono nową metodę oceny odpadów marmurowych jako krajowych zasobów kalcytu. Metoda służy jako przewodnik dla inwestorów i do podejmowania decyzji w branży kalcytu w Turcji. W artykule przedstawiono prace badawcze prowadzone w celu określenia jakości produktu - zmikronizowanego kalcytu z odpadów marmurowych oraz przegląd sytuacji rynkowej producentów regionalnych. Celem artykułu jest scharakteryzowanie czterech różnych odpadów marmurowych i określenie potencjału produkcji kalcytu o wymaganej jakości w Turcji. Zaproponowano kontrolę jakości produktów poprzez testy aplikacyjne, w tym pomiary niektórych parametrów.
Źródło:
Inżynieria Mineralna; 2020, 2, 1; 21-28
1640-4920
Pojawia się w:
Inżynieria Mineralna
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effect of Recycled Tire Rubber and Marble Waste on Fresh and Hardened Properties of Concrete
Autorzy:
Djebien, Rachid
Bouabaz, Amel
Abbas, Yassine
Powiązania:
https://bibliotekanauki.pl/articles/27314703.pdf
Data publikacji:
2022
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
recycling tire rubber
marble waste
green concrete
properties
odpady gumowe
odpady marmurowe
recykling
beton
Opis:
This paper investigates the effect of simultaneous adding of recycled tire rubber (RTR) and marble waste (MW) as fine aggregates on the properties of concrete. To achieve this objective, the particles size distribution of crushed sand (CS) was corrected by the use of marble waste sand (MWS), and RTR was used by volumetric substitution (1%, 2%, 3% and 4%) of aggregates in concrete. The fresh properties were investigated using the slump, density and air content tests. Hardened properties were investigated through the compressive strength, flexural strengths, pulse velocity, elastic modulus and water absorption. The obtained results showed that the increase in the substitution rate of RTR reduced the fresh and hardened properties of concrete containing marble waste sand. However, with low substitution rates the properties of concrete remain satisfactory and the utilization of RTR and MWS leads to making a green concrete while protecting the environment.
Źródło:
Civil and Environmental Engineering Reports; 2022, 32, 1; 218--239
2080-5187
2450-8594
Pojawia się w:
Civil and Environmental Engineering Reports
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Shrinkage and Absorption of Sand Concrete Containing Marble Waste Powder
Autorzy:
Djebien, Rachid
Abbas, Yassine
Bouabaz, Amel
Ziada, Yasser Nacereddine
Powiązania:
https://bibliotekanauki.pl/articles/27314704.pdf
Data publikacji:
2022
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
sand concrete
marble powder
waste
shrinkage
absorption
kruszywo betonowe
proszek marmurowy
odpady
wchłanianie
Opis:
In the context of growing scarcity of natural resources, the high demand of aggregates and the difficulties to open new quarries, several studies were carried out to study the possibility of reuse of waste and industrial by-products to replace traditional materials which would run out, replace materials when transport distances increase to reduce construction costs and protect the environment. This experimental study aims to investigate the effect of marble waste used as powder on the shrinkage and absorption of sand concrete in order to reuse it in the production of sand concrete. To achieve this goal, several sand concrete mixtures containing different substitutions rates of marble powder (4, 8 and 12%), and different Water / Cement ratio (0.71, 0.74, 0.77) were produced. Then, the evolution of the shrinkage and absorption values of sand concrete mixtures was studied. The obtained results showed that marble waste powder plays a positive role in reducing of shrinkage and absorption values of sand concrete and lead to the production of eco-friendly sand concrete.
Źródło:
Civil and Environmental Engineering Reports; 2022, 32, 1; 240--254
2080-5187
2450-8594
Pojawia się w:
Civil and Environmental Engineering Reports
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Experimental Investigation on the Effect of Marble powder on the performance of Selt-Compacting Concrete (SCC)
Autorzy:
Djebri, N.
Rahmouni, Z. E.
Belagraa, L.
Powiązania:
https://bibliotekanauki.pl/articles/89192.pdf
Data publikacji:
2017
Wydawca:
Politechnika Wrocławska. Wydział Geoinżynierii, Górnictwa i Geologii. Instytut Górnictwa
Tematy:
self-compacting concrete
SCC
marble powder
MP
mechanical properties
rheological characteristics
environment
Opis:
The self-compacting concretes (SCC’s) are characterized by their high fluidity so that they could be placed without any vibration. The effect of fillers addition on the behavior of SCC in fresh and hardened state is of great importance. This incorporation of marble powder aims to preserve the environment and to widen its use in the future in SCC formulation. The present research experimental program examines the effect of the partial substitution of cement with marble powder on the characteristics of self-compacting concrete in fresh and hardened state. Thus, the marble powder (MP) was introduced into the composition of self-compacting concretes at dosages of 10%, 20% and 30%. Three water cement ratios (W/C) of 0.4, 0.5 and 0.6 were maintained for the studied mixtures. The reference one with 100% of cement served as a control concrete mix. Finally, it can be concluded that such valuation of the marble waste could be beneficial for self-compacted concrete formulation.
Źródło:
Mining Science; 2017, 24; 183-194
2300-9586
2353-5423
Pojawia się w:
Mining Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Evaluation of flocculation behavior of marble powder suspensions
Autorzy:
Duzyol, S.
Powiązania:
https://bibliotekanauki.pl/articles/951841.pdf
Data publikacji:
2015
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
flocculation
marble powder
water soluble polymer
starch
turbidity
Opis:
In this study, flocculation of marble powder suspensions was investigated depending on a polymer type and dosage. Polyacrylamide was used as a synthetic polymer, while starch was used as a natural polymer. The effect of polyacrylamide type was also examined using anionic, cationic and non-ionic polyacrylamides. Flocculation of suspensions was ascertained by turbidity measurements. It was found that anionic and especially non-ionic polymers flocculated the marble powder suspension more strongly than starch and cationic polymer. On the other hand, it was observed that the sequential addition of starch and polymer did not improve flocculation of suspension. On contrary, sequential addition of flocculants caused re-dispersion of the flocculated suspension. When a non-ionic polymer was used as the flocculant, the reached minimum turbidity of suspension was measured to be 38 NTU (nephelometric turbidity unit).
Źródło:
Physicochemical Problems of Mineral Processing; 2015, 51, 1; 5-14
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Precipitated calcium carbonate production, synthesis and properties
Autorzy:
Erdogan, N.
Eken, H. A.
Powiązania:
https://bibliotekanauki.pl/articles/110023.pdf
Data publikacji:
2017
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
precipitated calcium carbonate
waste marble powder
whiteness
Opis:
Calcium carbonate (CaCO3) is the most widely used filler material in paper, paint, plastic, food, ceramic, cosmetic, medicine and other industries. In the present paper, precipitated calcium carbonate (PCC) has been produced from waste marble powder (WMP) by the Calcination-Dissolution-Precipitation (CDP) method. Calcination, dissolution and precipitation experiments were carried out under various conditions including : calcination temperature (800, 850, 900, 950 and 1000 °C), dissolution time (2.5, 5.0, 7.5 and 10.0 min) and precipitation time (2.5, 5.0, 7.5, 10.0, 12.5 and 15.0 min). Then, XRF, XRD, SEM, particle size, whiteness, brightness and yellowness analyses were performed for the characterization of the produced PCC materials. The analyses showed that the precipitate was mainly micrometer-sized (d50 = 1.682 μm) rhombohedral calcium carbonate crystals with 54.5% CaO. The whiteness, brightness and yellowness tests of the precipitates, conducted by Datacolor Elrepho 450x spectrometer, were determined to be 91.28, 98.2 and 1.99%, respectively. It was finally concluded that the produced PCC material reasonably meets Turkish Standards (TS 11653/1995) and can be used in paper industry.
Źródło:
Physicochemical Problems of Mineral Processing; 2017, 53, 1; 57-68
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A combined hydrocyclone - electrocoagulation treatment for different types of industrial wastewater
Autorzy:
Farghaly, Mohamed G.
Attia, H.
Saleh, H. A.
Ramadan, A. M.
Abdel Khalek, M.A.
Powiązania:
https://bibliotekanauki.pl/articles/1448028.pdf
Data publikacji:
2021
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
hydrocyclone
electrocoagulation
paper industry
iron industry
marble industry
granite industry
Opis:
Every year, a large amount of mineral processing wastewater is discharged from various industries into the environment which is considered a challenging task not only because of its large volume, but more importantly, its hazardous components, while its reuse as feedwater without proper treatments causes great harm to the final product of these industries. Cost-effective methods are required to treat a wide range of industrial wastewater in a diverse range of conditions. In this study, a combined hydrocyclone-electrocoagulation system is tried to treat the wastewater for industries with high water consumption and high pollutants such as paper industry, iron and metal forming industry, and marble industry. The effects of the hydrocyclone operational parameters, such as feed inlet pressure and diameter, vortex finder diameter, apex diameter, and feed solids content, were investigated. In the case, wastewater of paper industry, the following optimum conditions $(P = 4.5$ bar, $D_o = 15.8 mm, D_u = 6 mm, D_i = 4 mm and c_s = 2.3%)$ were achieved. An overflow of about 90.58% water recovery and 21.45% solid at 75.92% separation efficiency was obtained. The results showed that the hydrocycloneelectrocoagulation treatment has efficiently treated the three different types of industrial wastewater. The chemical oxygen demand (COD), biochemical oxygen demand (BOD), total solid (TS), total suspended solids (TSS), colour and turbidity, were reduced sharply and met the effluent discharge or reuse standards. Also, compared with the hydrocyclone-treated wastewater, the hydrocyloneelectrocoagulation-treated wastewater was found to be more enhanced.
Źródło:
Physicochemical Problems of Mineral Processing; 2021, 57, 2; 143-155
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Eksploatacja podziemna kamieni blocznych - podstawowe aspekty geologiczne i górnicze
Underground extraction of dimension stone — basic geological and mining aspects
Autorzy:
Galos, K.
Guzik, K.
Powiązania:
https://bibliotekanauki.pl/articles/395119.pdf
Data publikacji:
2013
Wydawca:
Polska Akademia Nauk. Instytut Gospodarki Surowcami Mineralnymi i Energią PAN
Tematy:
eksploatacja podziemna
kamienie bloczne
marmury
wapienie
systemy eksploatacji
underground extraction
dimension stone
limestone
marble
mining systems
Opis:
Podziemna eksploatacja kamieni blocznych jest rozpowszechniona w wielu krajach europejskich, a także w Ameryce Północnej. Jej popularność będzie jednak niewątpliwie rosnąć, przede wszystkim w związku z uwarunkowaniami środowiskowymi i kwestią dostępności terenu. Metoda ta zapewnia często długoletnią działalność górniczą, umożliwiając eksploatację tylko wybranych partii masywu skalnego, bez konieczności usuwania nadmiernego nadkładu, przy zredukowanym do minimum wpływie na powierzchnię terenu oraz niższych kosztach rekultywacji w porównaniu do eksploatacji odkrywkowej. Eksploatacja podziemna w chwili obecnej dotyczy niemal wyłącznie skał osadowych (głównie wapienie) oraz niektórych metamorficznych (np. marmury). Najbardziej znane przykłady podziemnej eksploatacji kamieni budowlanych występują we Włoszech, a także w Wielkiej Brytanii, Portugalii i kilku innych krajach Europy południowej. Najczęstszą przyczyną uruchamiania eksploatacji podziemnej skał blocznych jest występowanie zapotrzebowania na materiały kamienne, których wydobycie metodą odkrywkową jest utrudnione bądź niemożliwe. Istotnym aspektem eksploatacji podziemnej musi być gwarantowana długoterminowa stabilność geomechaniczna pustek poeksploatacyjnych. Warunki geostrukturalne (tektonika, litologia) determinują zarówno plan wyrobisk podziemnych, jak też metody pozyskiwania bloków w przodkach eksploatacyjnych. Najczęstszym stosowanym systemem eksploatacji podziemnej jest system komorowo-filarowy. Istotna jest także możliwość prowadzenia eksploatacji wybranych części złóż, charakteryzujących się najkorzystniejszymi parametrami jakościowymi. Za podjęciem podziemnej eksploatacji przemawia również stwierdzany wielokrotnie wzrost możliwości pozyskania bloków w głębiej położonych partiach złóż. Powoduje to, że uzysk bloków w kopalniach podziemnych jest rzadko mniejszy niż 60%. W Polsce podziemna eksploatacja krajowych skał blocznych nie była dotychczas prowadzona. Najbardziej interesujące perspektywy rozwoju eksploatacji metodą podziemną mogą dotyczyć m.in. marmurów, serpentynitów i sjenitów na Dolnym Śląsku oraz wapieni (marmurów technicznych) w rejonie Krakowa i Kielc.
Underground extraction of dimension stone is widespread in many European countries and in North America. Its popularity will undoubtedly grow, mainly due to environmental considerations and the accessibility of deposits for extraction. This method commonly results in long-term mining operations, allowing for the extraction of only selected parts of the rock mass without the necessity of overburden removal, reduced impact on the surface environment, and lower costs of reclamation as compared to open pit mining. Currently, underground mining is almost entirely associated with sedimentary rocks (mainly limestone) and some metamorphic rocks (e.g. marble). The best-known examples of underground exploitation of building stones are found in Italy, the UK, Portugal, and several other countries in southern Europe. The most common reason for initiating underground dimension stone mining is demand for certain stone materials which cannot be obtained from opencast mining. An important aspect of such operations is guaranteed long-term geomechanical stability of post-mining voids. Geostructural conditions (tectonics, lithology) determine both the plan of underground workings, as well as the method of blocks at the mining faces. The room-and-pillar system is the most common operating system of extraction. It is important to have the opportunity for selective mining of the parts of a deposit showing the best quality parameters, which allows for higher yield of the blocks (rarely less than 60%). In Poland, the underground extraction of dimension stone has not yet been conducted. The most interesting prospects for the development of an underground operation method may include — among other materials — marble, serpentinite, and syenite in Lower Silesia and limestone (technical marble) in the area of Cracow and Kielce.
Źródło:
Zeszyty Naukowe Instytutu Gospodarki Surowcami Mineralnymi i Energią PAN; 2013, 84; 25-36
2080-0819
Pojawia się w:
Zeszyty Naukowe Instytutu Gospodarki Surowcami Mineralnymi i Energią PAN
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Some Remarks on the Significance of Gold Based on Byzantine Ekphraseis of Works of Art
Autorzy:
Garnczarska, Magdalena
Powiązania:
https://bibliotekanauki.pl/articles/1032079.pdf
Data publikacji:
2020-12-23
Wydawca:
Uniwersytet Łódzki. Wydawnictwo Uniwersytetu Łódzkiego
Tematy:
Byzantine aesthetics
ekphrasis
gilding
mosaic
marble
Opis:
The abundance of gilding is considered to be a particularly characteristic feature of Byzantine art. This attribute can be confirmed by even a cursory analysis of works of art. In short, Byzantine artists used gold on a large scale, showing great technical skill. It is therefore quite surprising that this issue has not yet received a separate, comprehensive study. Admittedly, researchers recognize the presence of gold but unfortunately, they almost do not go beyond general observations. On the one hand, they emphasize the primary role of the symbolic meanings of gold, and, on the other, they indicate the high material value of this precious metal. These comments are usually very general and their authors rarely refer to specific primary sources. Their observations, however, speak more about present-day ideas about Byzantine culture than about it itself. The indicated problem is an important and extensive task to be done, hence this paper is only an outline of the most important questions, each of which requires a separate and in-depth study. Therefore, this synthetic article introduces the most basic points associated with the understanding of gold in Byzantium. For this purpose, selected examples of Byzantine texts in which their authors referred to gold in a strictly artistic context are analysed. Thus, the main thesis is as follows: in Byzantine painting, gold, one of the most important devices of artistic expression, was used on a large scale primarily for aesthetic reasons.
Źródło:
Studia Ceranea; 2020, 10; 83-121
2084-140X
2449-8378
Pojawia się w:
Studia Ceranea
Dostawca treści:
Biblioteka Nauki
Artykuł
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