Wyniki wyszukiwania - Biblioteka Nauki

1

Sorption of light hydrocarbons on clays from the Oligocene Kiscell Clay Formation, Hungary

100%

Tóth J.

Mineralogia

|

2009

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tom Vol. 40, iss. 1/4

43--52

EN

Clays from Solymár (Hungary) were treated with volatile components of light hydrocarbon in order to investigate their ability to sorb these organic compounds. The clays were characterized using XRD, optical microscopy (thin sections) and CEC measurements. The contaminated samples were analyzed using ATD-GC-MS, Rock Eval and XRD. Volatilization of the fluid phase hydrocarbon was monitoring for 663 days. The quantity of volatilized hydrocarbon compounds reached 50.0–65.0% at the end of the experiment. All of the analyses indicate hydrocarbon pollution of the clay layers after the volatilization process. The gross compositions of the fluid and the sorbed phases are different; the total amount of cycloalkanes among the sorbed hydrocarbons is very low. The dominant sorbed components are toluene, xylenes, nC9, nC10, nC11 and nC7. Cyclohexane, methylcyclohexane, benzene, nC12 and nC13 also occur in lower concentrations. The geochemical and XRD results indicate that adsorption onto the external surfaces of the clay minerals was the main sorption process.

2

The using possibility of clay-rich overburden rocks from selected Polish deposits

100%

Bożęcki P. , Rzepa G.

Geology, Geophysics and Environment

|

2012

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tom Vol. 38, no. 4

457

EN

The objective of this work was an assessment of the possibility of utilization of selected clay-rich overburden rocks from selected rock raw material found in Polish deposits. For this purpose samples from 12 deposits in five different provinces of southern Poland (Małopolskie, Śląskie, Podkarpackie, Dolnośląskie and Świętokrzyskie) have been collected. Exploited mineral deposits from which samples have been taken belong to wide range of materials. They are for example dolomite (Rędziny), magnesite (Braszowice), limestone (Czatkowice and Morawica), rhyodacites (Zalas), clay materials for construction of ceramics (Harasiuki, Wala Rzedzińska, Kraniec, Wręczyca) and mineral aggregates like sand (Bielany at Sole and Wola Batorska). Main field of feasibility of using samples were components of waterproofing layers. Part of the samples was also tested for the possibility of their use in land reclamation. Mineral and chemical composition of the samples was analysed, using XRD and ICP-OAS methods, respectively. Grain size distribution was performed by using sieve analysis and by a laser particle size analyser. Exchangeable cations and cation exchange capacity were also estimated based on the concentration of displaced ions (such as Ba +, Fe +, Sr +, Al +, Mg +, Ca +, Na+, K+, Li+) by ammonium cation (from the 1 M ammonium acetate solution) and indicated cations. Results of this study show that none of the tested samples met all the requirements for components of hydro-isolation layer, and therefore they cannot be used for this purpose. In most cases this is an effect of unfavourable mineral composition (to high percentage of non-clay minerals) and/or chemical composition. Usually the amount of examined exchangeable cations was also incorrect. The applicability results for land reclamation showed a very large variation. Part of the samples has acquired the highest A class. However, some samples were also found to be characterized by the worst D class of reclamation utility.

3

Nowoczesne techniki opracowania danych pomiarowych z badań geotechnicznych Cz. II. Zastosowanie aproksymacji wielomianowej i aproksymacji metodą ruchomejśredniej do badania trójosiowego iłów

100%

Słowiński D. , Damicz J. , Szymański L. , Tran C.

Inżynieria Morska i Geotechnika

|

2011

|

tom nr 6

510-516

PL

Metodyka określania parametrów geotechnicznych z badań trójosiowego ściskania. Procedury odszumiania danych pomiarowych (filtrowanie, skracanie, wygładzanie). Przykład i wyniki praktycznego zastosowania metody ruchomej średniej metody wielomianowej. Analiza rynków i wskazówki praktycznej przydatności obu metod.

EN

Methodology of the determination of geotechnical parameters obtained from triaxial tests. Denoising procedures (filtration, reduction, smoothening) of measuring data. Example and the results of the application of moving average and polynomial methods. Market analysis of practical guidelines for application of both methods.

4

Immobilization of Catalase via Adsorption onto Natural and Modified Montmorillanit Analsim-Clay

100%

Alkan S. , Gür T. , Gür A. , Uruc H. , Demir H.

Polish Journal of Chemistry

|

2009

|

tom Vol. 83, nr 12

2089-2095

EN

Immobilization of the enzyme catalase on natural and modified montmorillanit analsimclays was investigated using a batch system. Such an immobilization does not result in enzyme in activation and constitutes a valuable method for immobilizing catalase at high ionic strength. In the immobilization process, the effect of pH, ionic strength and reaction temperature were chosen as parameters. Further more the optimization of immobilization conditions were studied using data obtained from experimental results. For the free catalase and three different immobilized catalase enzymes, the optimum pH values 8, 7, 7 and 8; reaction temperature 30°C; ionic strength 0.25 M were found. It was determined that enzyme activity for enzyme supported by natural clay was 73.3 percent, when it was retained during the storage at 4°C for a period of 60 days. It was observed that storage and operational stabilities of the enzyme in creased with immobilization. The results obtained show that montmorillanit analsim-clay is valuable and favour able support the simple adsorption of enzymes.

5

Problemy posadowienia na iłach plioceńskich śluzy stopnia wodnego w Malczycach

100%

Parylak K.

Inżynieria Morska i Geotechnika

|

2012

|

tom nr 1

25-28

PL

Opis i analiza właściwości iłów plioceńskich. Charakterystyka konstrukcji i posadowienia śluzy w Malczycach na podłożu ilastym. Przyczyny i skutki pęcznienia iłów. Badania i analiza wyników badań właściwości iłów i ciśnienia pęcznienia iłów.

EN

Description and analysis of Pliocene clays. Description of the foundation of Małczyce lock in clayey subsoil. Reasons and effects of clays swelling. Investigations and analysis of the results of swelling pressure tests and properties of clays.

6

Morphological Evaluation of Variously Intercalated Pre-baked Clay

100%

Ullah H. , Imtiaz A.

Polish Journal of Chemical Technology

|

2014

|

tom 16

|

nr 2

5-11

EN

The use of porous materials is enjoying tremendous popularity and attention of the advance scientific communities due to their excellent adsorptive and catalytic activities. Clays are one of the most important candidates in the porous community which shows the above mentioned activities after modifing with a different intercalating agent. The paper is focused on the infiuence of some inorganic intercalating agents (NaOH) on the morphology of the variously intercalated clay samples. The alkali metal was used as the inorganic intercalating agent. The effect of intercalation temperature, intercalation agent concentration and intercalation time on the pre-baked clay morphology were also part of the study. Scanning electron microscopy (SEM) study was performed to evaluate the morphological changes of the resultant intercalates. Different morphological properties were improved significantly in the case of the inorganically modified clay samples. Thus, such intercalations are suggested to be effective if the clays under study are to be used for different industrial process at elevated conditions.

7

The influence of water on various clay rocks

100%

Goc A. , Wojtasiak P. , Piotrowski J. , Stec M.

AGH Drilling, Oil, Gas

|

2018

|

tom Vol. 35, no. 1

83--105

EN

One of the challenges of any laboratory dealing with drilling fluids is to develop a mud that is also environmentally friendly and, on the other hand, inhibits the clay layers to a maximum. The article presents the influence of water on various samples of clay rocks characterized by different geological age. The research was carried out using the Linear Swelling Meter. The geological age, the environment in which the clay rock was formed, the depth of burial – all these factors affect the swelling properties of individual clay rocks. Knowledge of the swelling properties of clay rocks allows the proper selection of drilling fluid system.

8

The Turonian/Coniacian (T/C) boundary in the Upper Cretaceous of the Elbe Valley/Saxony (Germany)

100%

Troger K. , Wejda M.

Acta Geologica Polonica

|

1998

|

tom Vol. 48, no. 4

387-394

EN

Three lithofacies characterize the Turonian/Coniacian sequences in the Upper Cretaceous of the Elbe Valley. The marly lithofacies, between Weinbohla - Dresden - Heidenau, consists of marls and calcareous clays (Strehlen Formation). A transitional lithofacies, with alternations of marls, clays and blocky sandstones, follows to the southeast (area between Rosenthal - Pirna - Lohmen). A sandy lithofacies, with blocky sandstones, is developed even farther to the southeast (Elbsandsteingebirge). The T/C boundary is situated in the lower part of the Strehlen Formation in the marly lithofacies, known from several boreholes. Coniacian index ammonites are absent across the T/C boundary in the three investigated boreholes apart from a deformed and incomplete specimen of Placenticeras cf. orbignyanum (GEINITZ). Therefore, bivalves must be used to place the T/C boundary. The Didymotis event II (Dresden-Marienhof Borehole), with Cremnoceramus waltersdorfensis (ANDERT), lies at the top of the Upper Turonian M. scupini Zone. The rarity or absence of the bivalve Didymotis in the Dresden-Blasewitz and Graupa boreholes is caused by facies changes. The FAD of Cremnoceramus rotundatus (TROGER non FIEGE), especially the C. rotundatus Event (Graupa Borehole, Hinterjessen Marl), can be used to place the T/C boundary. A small interval below the FAD of C. rotundatus and above the Didymotis II event, which may belong to the basal Coniacian, yields Cremnoceramus waltersdorfensis (ANDERT), Cremnoceramus waltersdorfensis hannovrensis (HEINZ), Mytiloides carpathicus (SIMONESCU) and Placenticeras cf. orbignyanum (GEINITZ). In the sandy lithofacies fossils are rare. It is not possible to place the boundary in either the Herrenleite Sandstone or in sandstone d. In the marly lithofacies of the Upper Cretaceous of Saxony bracketing of the T/C boundary is possible by means of planktonic foraminifera. It is possible to identify the evolution of planoconvex double-keeled globotruncanids of the Dicarinella hagni - Dicarinella primitiva - Dicarinella concavata group from the Upper Turonian. In the Dresden-Blasewitz and Dresden-Marienhof boreholes this group is represented in the T/C boundary interval by Marginotruncana paraconcavata PORTHAULT and Dicarinella cf concavata (BROTZEN). They are of rare occurrence because they are facies controlled. It is not possible to recognize the boundary between the scheegansi and concavata zones because of the restricted occurrence and rarity of the index forms in the investigated sections. In the Dresden-Blasewitz and Dresden-Marienhof boreholes the benthonic species Stensioeina granulata (OLBERTZ) was identified.

9

Paleoecological analasis of the miospore assemblages from the borehole 39, Moscow region, Russia

100%

Mamontov D. A.

Geology, Geophysics and Environment

|

2015

|

tom Vol. 41, no. 1

106--107

EN

Palynological material was obtained from Upper Visean deposits in the borehole No 39 that is located on the left bank of the Oka River, on 105 km to the south-east of the Moscow in the Serpukhov district. The lithological sequence of the borehole generally consist of the limestones, stigmarian limestones, interbedded with clays and siltstones. Total twenty five palynological samples from the sandy siltstones and charcoal clays (deep interval 29.4–33.25 m) have been collected. All samples contained abundant well-preserved miospores. Two palynoassemblages have been defined. The palynoassemblage S1 is described from the sandy siltstone and stigmarian limestones of the depth interval 29.4– 29.59 m. The palynoassemblage S2 is established from the coaly dark clays that occurred at the depth interval 29.64–33.25 m. All palynoassemblages are dominated by Lycospora pusilla. Based on both the presence Cingulizonaes bialatus, Triquitrites comptus, (index-species of the CBd palynozone) and the occurrence of the Late Visean species Tripartites vetustus, Triquitrites marginatus, Schulzospora campyloptera, Calyptosporites arenaceousthe age of the palynoassemblages is defined as transitional Aleksinian-Mikhaylovian. The results well corresponded with data of miospore zonal scheme for Carboniferous of Russian Platform (Makhlina 1993). Paleoecological interpretation of the obtained palynoassemblages has been carrying out. General model of the paleoecological analysis is explained by the connection between the Carboniferous miospore taxa and their parent plants. Natural affinity of the miospores is determined by the comparison of dispersed material with the in situspore findings that are elucidated in paleobotanical articles (more detail see Balme 1995, Orlova et al. 2014). In concordance with the comparison of the dispersed spores and insitudata, the miospore genera of the palynoassemblages have been subdivided into six paleobotanical patterns: arborescent lycopsids (Lycospora-producing plants), subarborescent lycopsids were produced the “densospores” (Densosporites,Vallatisporites, Cingulizonates), spores of ferns (Leiotriletes, Punctatisporites, Granulatisporites, Cyclogranisporites, Knoxisporites, Raistrikia, Tripartites, Triquitrites, Acanthotriletes, Convolutispora), miospores (prepollen) of seed ferns (Schulzospora, Remysporites, Geminospora, Rotaspora), spores of the sphenopsids (pars Calamospora) and pattern of unknown natural affinity (Diatomozonotriletes, Camarozonotriletes, Iugisporis, Simozonotriletes,Waltzi spora, Calyptosporites). Abovementioned paleobotanical patterns are generalized into three paleoecological units: forest mire (arborescent and sub-arborescent lycopsids), non-forest mire (ferns, seed ferns and sphenopsids) and problematic one (unknown natural affinity). Accordingly, palynoassemblage S1 is dominated by arborescent lycopsids (66%). Sub-arborescent lycopsids (11%) and ferns (13%) were quite common in the plant communities. The seed ferns elements (2%) and sphenopsids (3%) were rare in the local palaeoflora. On the one side the forest-mire related miospores were increased upward the sequence (from 70% up to 88%), on the other side the percentage of the non-forest mire elements (from 26% up to 8%) were constant decreased in the same direction. The high percentage of forest mire unit is largely due to short predominance of the sub-arborescent lycopsids (21%). Palynoassemblage S2 is differed from the preceding one by the increased role of the arborescent lycopsids (75%) in the plant communities. The percentage of the sub-arborescent lycopsids (2%) is distinctive low. Content of the ferns (11%) is slightly decreased versus the previous palynoassemblage. Ratio of the sphenopsids (5%) and seed ferns (3%) is easily enlarged. Forest mire vegetation type was constantly dominated (75%) in the plant cover of the studied locality while the nonforest one (19%) was less common than the same from the palynoassemblage S1. The percentage of the ferns (from 3% up to 21%) and sphenopsids (from 3% up to 7%) is gradually increased during the deposition time of the palynoassemblage S2. As result of the paleoecological interpretation of the palynoassemblage the change of the vegetation types during Late Visean time has been recorded. Generally content of the forest mire related miospores is decreased upward the section while the percentage of the non forest mire elements is constantly increased. Most probably that short prevalence of the sub-arborescent lycopsids at the uppermost part of the palynoassemblage S1 can be related with initial transgression phase. From the one side this proposal is well corresponded with data of the Habib & Groth (1967) referred that Lycospora-producing arborescent lycopsids were more sensitive for higher salinity during the sea onlap and it could replaced by the stress-tolerant Densospores-producing subarbo-rescent lycopsids. From the other side the upper-most part of the palynoassemblage S1 determined from the stigmarian limestone that indicated the brackish condition. Besides the high percentage and diversity of the fern derived miospores coincides with the high portion of clastic material in deposits. It is explained by that the fern preferred open and opportunistic condition of sand bars. Apparently, the plant cover change is very similar to the same vegetation type’s ratio was marked by the previous researches in the Upper Visean localities from the Kaluga and Tula regions (Mamontov et al. 2012).

10

Study of Zeolite Phase Made from Rice Husk Ash and Sidrap Clay

100%

Armayani M. , Mansur M. , Asra R. , Irwan M. , Ramadhanty D. , Subaer S. , Abdullah M. M. A. B. , Aziz I. H. A. , Jeż B. , Nabiałek M.

Archives of Metallurgy and Materials

|

2023

|

tom Vol. 68, iss. 1

269--274

EN

Zeolite has been successfully synthesized from clay and rice husk ash in the form of powder by using the hydrothermal method with variations in chemical compositions of alkaline solution and the amount of rice husk ash. The clay raw material was obtained from the Sidrap area of South Sulawesi and rice husk ash is obtained from the burning pile of rice husks. Sidrap clay and rice husk ash were activated using an alkaline solution of NaOH and varied rice husk ash and the addition of AlCl3. The addition of AlCl3, an alkaline solution of NaOH and H2O was used in the amount of 25.5 grams and variations of rice husk ash were 2.5 grams and 6.5 grams. Meanwhile, without the addition of AlCl3, an alkaline solution of NaOH and H2O was used for 20.5 grams and variations of rice husk ash from 2.5 grams and 6.5 grams. Then the mixture was then put into an autoclave with a temperature of 100°C for 3 hours. The basic material used in the manufacture of zeolite is carried out by X-ray Fluorescence (XRF) characterization to determine the constituent elements of basic material, which showed the content of SiO2 was 45.80 wt% in the clay and 93.40% in the rice husk ash. The crystalline structure of the zeolite formed was characterized by X-Ray Diffraction (XRD). It was found the resulting zeolite were identified as Zeolite-Y, Hydrosodalite, and ZSM-5. The microstructure properties of the resulting zeolite were determined by using Scanning Electron Microscopy (SEM).

11

Stress–dilatancy behaviour of remoulded Fujinomori clay

100%

Szypcio Z. , Dołżyk-Szypcio K.

Studia Geotechnica et Mechanica

|

2023

|

tom Vol. 45, nr s1

247--252

EN

The effect of the degree of consolidation and the stress path on the behaviour of remoulded Fujinomori clay for drained triaxial compression and extension was analysed using the Frictional State Concept. It is shown that the stress–dilatancy behaviour can be approximated by a linear general dilatancy equation given by the critical frictional state angle and two soil parameters. The newly formulated dilatant failure state is represented on the stress ratio plastic dilatancy plane by points lying on the friction state line defined by the friction state angle and the Friction State Concept parameters α=0 and β=1. It has been shown that the stress ratio–plastic dilatancy relationship, which is very rarely used in the interpretation of test results, is important for a complete description of the behaviour of soils during shearing.

12

Characterization of the Chemical Properties of Deposited Red Clay Soil Using GIS Based Inverse Distance Weighted Method in Kirkuk City, Iraq

100%

Salahalden V. F. , Shareef M. A. , Al Nuaimy Q. A. M.

Ecological Engineering & Environmental Technology

|

2023

|

tom Vol. 24, iss. 7

46--60

EN

This study focuses on the physical and chemical properties of soils and their geographical distribution, with a specific focus on red clay. The inverse distance weighting (IDW) technique, integrated with Geographic Information Systems (GIS), was employed to predict the chemical characteristics of the soil. Sampling was conducted at twenty-one locations in three areas: Bor Mountain, Jambor, and Kirkuk Hills, all located within Kirkuk City. Seven soil properties were examined: acidity, organic matter content, total dissolved salts (TDS), gypsum, chlorides, and sulfates. The chemical analysis revealed that the soil pH ranged within an acidic range. One sample exhibited a high TDS level. Chloride levels varied within a specific range. The concentration of organic matter in the soil exhibited variability. Sulfur trioxide and gypsum concentrations were found to be below average in the study region. The IDW technique effectively mapped the distribution of the different soil parameters within Kirkuk City, demonstrating a range from good to excellent accuracy. Additionally, a cross-validation method was employed to assess the correlation between the fundamental and investigated chemical properties. The results showed good to excellent degrees of correlation in the different structures studied.

13

The effect of 200 MPa pressure on specific surface area of clay

100%

Koszela-Marek E.

Studia Geotechnica et Mechanica

|

2014

|

tom Vol. 36, nr 4

3--6

EN

The paper presents the results of laboratory studies of the 200 MPa pressure effect on specific surface area of clay. The original high-pressure investigation stand was used for the pressure tests. Determination of the specific surface area was performed by the methylene blue adsorption method. The results of the specific surface area test were compared for non-pressurized clays and for clays pressured in a high-pressure chamber. It was found that the specific surface area of pressurized soil clearly increased. This shows that some microstructural changes take place in the soil skeleton of clays.

14

Morphological Evaluation of Variously Intercalated Pre-baked Clay

100%

Ullah H. , Imtiaz A.

Polish Journal of Chemical Technology

|

2014

|

tom Vol. 16, nr 2

5--11

EN

The use of porous materials is enjoying tremendous popularity and attention of the advance scientific communities due to their excellent adsorptive and catalytic activities. Clays are one of the most important candidates in the porous community which shows the above mentioned activities after modifing with a different intercalating agent. The paper is focused on the infiuence of some inorganic intercalating agents (NaOH) on the morphology of the variously intercalated clay samples. The alkali metal was used as the inorganic intercalating agent. The effect of intercalation temperature, intercalation agent concentration and intercalation time on the pre-baked clay morphology were also part of the study. Scanning electron microscopy (SEM) study was performed to evaluate the morphological changes of the resultant intercalates. Different morphological properties were improved significantly in the case of the inorganically modified clay samples. Thus, such intercalations are suggested to be effective if the clays under study are to be used for different industrial process at elevated conditions.

15

Stopień YSR miarą prekonsolidacji iłów formacji poznańskiej

100%

Izbicki R. , Stróżyk J.

Zeszyty Naukowe Politechniki Białostockiej. Budownictwo

|

2006

|

tom Z. 28, t. 1

117-126

PL

W pracy przedstawiono wyniki badania prekonsolidacji części stropowej mioplioceńskich iłów formacji poznańskiej z rejonu Wrocławia. Wielkość prekonsolidacji określano poprzez wartość stopnia naprężenia uplastyczniającego YSR oraz naprężenia uplastyczniającego 'y. Naprężenie 'y należy uznać za główny parametr stanu gruntów spoistych. Stwierdzono, że naprężenie 'y przyjmuje wartości od 420 do 1100 kPa i rośnie wraz z głębokością zalegania gruntu, natomiast wyznaczona wartość stopnia YSR wykazuje duże zróżnicowanie od 3,7 do 6,5 i nie wykazuje związku z głębokością zalegania gruntu.

EN

In paper the results of examinations the preconsolidation of the Poznań formation clays from the region of Wrocław were presented. The preconsolidation was being determined through the value of Yield Stress Ratio YSR and yield stress 'y. Yield stress is one of the main parameter of the state of cohesive soils. The yield stress value for Poznań clays was from 420 for 1100 kPa and was growing along with depth, however the determined value of the YSR was showing big diversity from 3.7 for 6.5.

16

Laboratory studies on benzene sorption processes in clay formations

100%

Wołowiec K. , Malina G.

Geology, Geophysics and Environment

|

2015

|

tom Vol. 41, no. 1

43--51

EN

The presented studies focused on benzene sorption mechanisms in the semi-permeable geological formations (aquitards). Clay formations were taken under consideration as not well investigated so far. Natural clay samples artificially contaminated with benzene were used in batch and column experiments to determine benzene partitioning and retardation in the studied clay material, and to reflect natural groundwater flow conditions. Column tests were carried out under controlled water flow conditions and using undisturbed clay samples. Benzene concentrations in tested samples (water and soil) were determined by gas chromatography (GC-FID). The linear sorption isotherm was used to fit the experimental data, as well as calculate the distribution coefficient (K d = 0,042) and the retardation factor (R = 1.21) of benzene in the studied clay material. These parameters are important for mathematical modelling of the fate and transport of benzene through the semi-permeable formations (clays) to assess the associated risk and to prevent groundwater resources from contamination.

17

Numerical Modeling of the Pipeline Uplift Mechanism in Clay

88%

Abdelfateh K. , Mohamed B. , Fattah M. Y.

Archives of Hydro-Engineering and Environmental Mechanics

|

2021

|

tom Vol. 68, nr 2

119--135

EN

Buried pipelines are a vital infrastructure and are mainly used to transport energy carriers and other essential products. The pipes are generally buried in the upper layer of soil deposits and, therefore, are highly affected by different geo-environmental conditions. The various pathological cases recorded in the world are caused by the degradation of structures in contact with swelling soils, the fact that necessitates a full understanding and investigation of such a phenomenon. This paper presents a method for the pipeline behavior modeling based on the finite element analysis by using PLAXIS 3D software, aimed at the determination of the pipe bending moment, displacement over its length, and the evaluation of vertical stresses in soil under the pipe. A parametric study has been carried out to investigate the effect of the pipe burial depth and the soil cohesion. The finite-element results have been compared with experimental data from the literature. It was found that, unlike laboratory models, the numerical analysis can account for the internal pressure in the pipe and the depth of the pipe burial. The finite-element analysis showed that the presence of fluid pressure inside the pipe results in a decrease in the maximum swelling of the soil by about 95%. The displacement of the pipe is considerably affected by the burial depth. The vertical stress at one end of the pipe can be greater than that at the other end in the case of a pipe under internal pressure, while in the case of an empty pipe, the values are very close at both ends. The numerical analysis shows that an increase in the pipe internal pressure leads to a decrease in its vertical displacement.

18

An attempt to improve mechanical properties of brick produced from El-Maghara coal washing plant waste

88%

Ramadan A. M. , Saleh A. M. , Taha T. A. , Moharam M. R.

Physicochemical Problems of Mineral Processing

|

2001

|

tom Vol. 35

153-160

EN

Treatment of wastes became a vital demand to maintain the environment as clean as possible . The treatment of wastes and reuse of their constituents in industry will be helpful for this trend as well as for economy. Flotation technique is one of the important separation techniques that can be applied for treatment of wastes efficiently. The filter cake of El-Maghara coal washing plant was one of these wastes which contains a considerable amount of clay. This filter cake was treated in a previous work by flotation in order to clean it from the contained fine coal. The residual clay was tested as a raw material to produce brick models with acceptable mechanical properties. Improvement of the mechanical properties of such brick models by mixing such clay with sand is exactly the main objective of this work. The effect of different factors such as, weight percent of sand and its particle size on the mechanical properties of the brick models was investigated. It was found that 20 % and 60 % of sand sample characterized by size distribution of - 1500 + 0 žm and - 500 + 0 žm respectively are enough to achieve a considerable extent of improvement in the mechanical properties of the clay brick produced.

PL

Poprawa mechanicznych właściwości cegieł wykonanych z mułu węglowego przez dodanie piasku, stanowiła główny cel badań. Wpływ takich parametrów jak zawartość piasku, skład ziarnowy na właściwości mechaniczne produkowanych cegieł był badany. Zostało ustalone, że obecność 20% piasku o uziarnieniu –1500 žm oraz 60% piasku o uziarnieniu –500 žm pozwala na wyraźną poprawę mechanicznych właściwości produkowanych cegieł.

19

Clay/nanocomposite hydrogels : In review

88%

Kurama H. , Şengel S. B.

Physicochemical Problems of Mineral Processing

|

2023

|

tom Vol. 59, iss. 5

art. no. 165991

EN

The development of advanced materials those are stronger, more rigid, lighter, hotter and self-renewable than existing materials has been the rising point of many research studies conducted in recent years. Within this scope, the interest to production of nanostructured materials is received considerable attention worldwide due to their potential positive contribution to wide variety of technological areas such as electronics, catalysis, adsorbents, ceramics, magnetic data storage, structural components etc. In these efforts polymer nanocomposites as the form of hydrogels, reinforced with well-dispersed layered silicate, typically montmorillonite can be given as a one of the promising composite material. However, long-standing problems for polymer-clay nanocomposites include actual exfoliation of clay particles in discrete layers, uniform distribution of clay layers throughout the polymer, and randomness of clay sequences. For the exfoliation of clay particles, although the chemical modification of clay minerals in aqueous media is the well-known and more general way applied by researchers, the physical pathway method performed by high-energy ball mills is also gaining increasing attention as an alternative pretreatment way. Grinding of crushed materials is one of the key processes in the mineral and cement industry, but the increased concern on the preparation of fine-grained powders (nano powders) or the manufacture of composites with desirable properties, especially performed with use of high-energy ball mills, has led to significantly widen the usage field of grinding. Undoubtedly, the main reason for these efforts is to improve the performance of existing materials. In this paper the fundamental concepts, classification, physical and chemical characteristics and the production methods of clay/polymer nanocomposites was briefly reviewed base on the composite hydrogel. Particular attention was paid to the pre-treatment (exfoliation) of clays with high-energy ball mills, which is increasingly being accepted as an alternative method to eliminate the negative effects of chemical treatment in some composite forms.

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The influence of atmospheric conditions on the migration of diesel fuel spilled in soil

88%

Vuruna M. , Veličković Z. , Perić S. , Bogdanov J. , Ivanković N. , Bučko M.

Archives of Environmental Protection

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2017

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tom Vol. 43, no. 1

73--79

EN

The most common chemical’s spills in typical transportation accidents are those with petroleum products such as diesel fuel, the consequence of which is an extensive pollution of the soil. In order to plan properly fuel recovery from the soil, it is important to gain information about the soil depth which may be affected by pollutant and to predict the pollutant concentration in different soil layers. This study deals with the impact of basic atmospheric conditions, i.e. air temperature and humidity on the diesel fuel migration through the soil. The diesel fuel was spilled into columns (L = 30 cm; D = 4.6 cm) filled with sandy and clay soil samples, and its concentrations at various depths were measured after 11 days under various air temperature (20 and 40°C) and relative humidity (30–100%) conditions. The effects observed were explained by understanding physical processes, such as fuel evaporation, diffusion and adsorption on soil grains. The increase in temperature results in higher fuel evaporation loss and its faster vertical migration. The relative humidity effect is less pronounced but more complex, and it depends much on the soil type.