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1

Performance of Limestone as a Multi-Media Filter for Manganese Removal from Groundwater

Ahmedi Figene, Thaqi Premton, Tosuni Kaltrina

Journal of Ecological Engineering

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2023

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Vol. 24, nr 6

385--391

EN

According to Council Directive 98/83/EC on the quality of water intended for human consumption, concentration of the manganese in the drinking water should not exceed 0.05 mg/l. However, this level of manganese concentration is higher ingroundwaterof a community (Vitia town) in Kosovo. Groundwater is used for drinking supply of some villages and is only chlorified continuing to the reservoir from where is gravitationallydisseminated to the villages. The manganese level of the water is at the range 0.3 to 0.6 mg/l. Limestone has been provenby many researchers to be a very effective filter material in manganese removal for groundwater.A miniature filtration unit was modeled to investigate the removal efficiency of manganese.The unit consists of local limestone, where a single materialis folded in three layers of different grainsizes. In fact, the aim of this paper was to assess whether limestone as a single material acting as a "multi-media filter" can reduce the manganese concentration in groundwater. On the basis of the analysis of the single snapshot sample,the removal of manganese achieved more than 95% in filtered water. Particularly, this study demonstrates that filtering the water through three layers of different grain sizes of limestone ("multi-media limestone filter") can be a good alternative for manganese removal in groundwater.

2

Możliwość zastosowania mączek wapiennych jako dodatku w betonie

Bajorek Grzegorz, Barć Maciej, Kosturkiewicz Łukasz

Inżynieria i Budownictwo

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2023

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R. 79, nr 1-2

9--13

PL

W artykule przedstawiono badania efektów zastosowania w betonie 8 różnych mączek wapiennych, poprzez zastąpienie nimi aktywnego dodatku pucolanowego. Wyniki badań potwierdziły ich przydatność, a ostateczna ocena może nastąpić na podstawie badań wstępnych. Użycie mączek wapiennych bezpośrednio do betonu wpisuje się w działania zmierzające do obniżenia emisyjności tego bardzo ważnego materiału konstrukcyjnego.

EN

The article presents research on the effects of using 8 different limestone powders in concrete by replacing the active pozzolanic additive with them. The results of the research confirmed their suitability, and the final assessment may be based on initial test. The use of lime powder directly into concrete is part of the activities aimed at reducing the emissivity of this very important construction material.

3

The occurrence of Capitanian fusulinoidean fauna and giant bivalve Alatoconchidae from Khao Khwang Formation, Central Thailand

Charoentitirat Thasinee, Sirot Sutharat, Maneerat Warunee

Geotourism / Geoturystyka

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2023

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nr 1-2 (72-73)

14

EN

Khao Khwang Formation is widely distributed in central Thailand. It is represented by Late Pennsylvanian to Middle Permian thick-bedded limestone with chert nodules. Rock samples belonging to this formation have been collected. They are light to dark grey, thick-bedded to massive limestone with black nodular cherts. The abundant and extraordinarily gigantic bivalve Alatoconchidae together with fusulinoidean fauna (Verbeekina verbeeki, Colania douvillei and Pseudodoliolina pseudolepida), fragments of coral, ammonoid, brachiopod, sponge, gastropod, etc. were observed. Based on the characteristic fusulinoidean fauna, it indicates Capitanian in age. Microscopically, limestone samples were classified as bioclastic rudstone and packstone. The detailed lithologic and carbonate microfacies observations, Alatoconchidae beds, deposited parallel to the bedding plane and related with oncoids and microbial, are autochthonous in shallow marine. Condensed accumulation of other fossil fragments found in the study areas might be transported by gravity flow.

4

Reddish multiphase infillings in the megalodontid bivalves and solution voids in Julian Alps – NW Slovenia

Slapnik Lucija, Rožič Boštjan, Gale Luka, Rožič Petra Žvab, Waśkowska Anna

Geotourism / Geoturystyka

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2023

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nr 1-2 (72-73)

64--64

EN

At a nature-preserve protected site in the Julian Alps (NW Slovenia), in the Pod Peski valley, red fillings of megalodontid bivalves occur within the Upper Triassic Dachstein limestone. Based on optical and cathodoluminescent microscopy and X-ray fluorescence (XRF) analysis, four generations of shell fillings were recognized, some of which contain both cement and sediment subgenerations. Logging and sampling of the limestone sequence a few meters below and above the “main” layer containing the megalodontids mentioned above revealed that the limestone is characterized by solution voids similar to the megalodontids. Namely, these voids are also filled with reddish multigeneration sediment with alternating calcite cement. Adjacent neptunian dykes were studied to clarify their influence on the last generation fillings. Two of them, located directly on the “main” layer with red-filled megalodontids, contain planktonic foraminifera, indicating Middle Jurassic or younger age. The next two neptunian dykes are located directly above the “main” layer, and one contains clasts with calpionellids characteristic of the Late Jurassic/Early Cretaceous. The last dyke explored is located a few tens of meters from the “main” layer and is several hundred meters long. In a few sample from this dyke Early Cretaceous planktonic foraminifera were identified. Microscopic analysis revealed that the reddish sedimentary fillings are part of a complex palaeokarst system that produced the first three generations of fillings, and in the last (fourth) generation we noted similarities between the megalodontid fillings and neptunian dykes on the “main” bedding plane. In addition, a Santonian–Maastrichtian sedimentary fill with globotruncanid foraminifers were discovered in the upper part of the succession in one of the solution voids.

5

Determination of physical and mechanical properties of limestones used as marble in Tut-Adiyaman Region in Turkey

Rizaoğlu Tamer, Çoşkun Canberk, Camuzcuoğlu Murat

Mining Machines

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2022

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vol. 40, iss. 3

141--148

EN

This study aimed to reveal the petrography and physical-mechanical properties of limestones, which have an important reserve and are used as marble, in Tut district of Adıyaman province, which is one of the important cities of southeast Anatolia. As a result of petrographic analysis of the rock known commercially as Emprador, it was determined that it is bioclastic limestone with abundant nummulite fossils. Density, dry and saturated unit weight, water absorption, surface roughness, abrasion resistance and uniaxial compressive strength tests were applied to determine the physical and mechanical properties of the limestones. According to the test results obtained, the density of the limestones, dry unit weight, saturated unit weight, water absorption by weight, water absorption by volume, average surface roughness, ten points roughness average, maximum roughness value, Bohme abrasion resistance and uniaxial compressive strength values were determined as 2.486 gr/cm3, 2.478 gr/cm3, 2.52 gr/cm3, 1.482%, 3.644%, 3.31 μm, 16.24 μm, 20.03 μm, 8.958 cm3/50cm2 and 1004.03 kgf/cm2 respectively. The results show that the limestones in and around Tut (Adıyaman) county can be used in large areas for decorative purposes, with their physical and mechanical properties, as well as their colour tone and the texture formed as a result of the calcite veins being shaped like a natural pattern.

6

Zielony potencjał cementu wapiennego w aspekcie redukcji śladu węglowego wbudowanego w konstrukcjach mostowych

Górak Piotr, Mofina Paweł, Guzikowski Łukasz

Materiały Budowlane

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2022

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nr 10

110--113

PL

W artykule przedstawiono wyniki badań, jakie uzyskano w przypadku betonu mostowego wykonanego na cemencie portlandzkim wapiennym CEM II/A-LL. Zastosowanie tego cementu pozwala na znaczną redukcję śladu węglowego wbudowanego w konstrukcjach mostowych, średnio o 12% w porównaniu z rozwiązaniami na bazie cementów CEM I. Kamień wapienny, jako główny składnik nieklinkierowy cementu, wprowadza do kompozytów cementowych wiele dodatkowych właściwości, które również zostały przedstawione w artykule. W przyszłości, w przypadku ograniczonej dostępności dobrej jakości innych, popularnych składników cementu (S, V) oraz wapienia i opartych na nim cementów może stać się naturalnym wyborem do redukcji śladu węglowego w betonie.

EN

In this article presented test results which obtain for bridge concrete made on Portland limestone cement CEM II/A-LL. Deployment of this cement allows for significant embodied carbon footprint reduction in bridge structures averaging 12% in comparison for CEM I solutions. Limestone as a major non-clinker cement’s constituent is characterized by a number of additional properties in cement composites, which were also presented in this article. In the near future, with the limited availability of good quality other popular ingredients of cement (S, V), limestone and cement based on it may become a natural choice for reduction of carbon footprint in concrete.

7

Wapień w składzie kompozytów cementowych

Batog Maciej, Giergiczny Zbigniew

Materiały Budowlane

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2022

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nr 12

119--124

PL

W artykule przedstawiono wpływ wapienia (LL) na cechy fizyczne i chemiczne stwardniałego zaczynu cementowego. Przeanalizowano właściwości cementu portlandzkiego wapiennego CEM II/A, B-LL oraz cementu portlandzkiego wieloskładnikowego CEM II/A, B-M (S, LL) i CEM II/A, B (V-LL). Podkreślono znaczenie wielkości wskaźnika w/c w przypadku poziomu wytrzymałości i trwałości kompozytów cementowych, w których głównym składnikiem jest wapień (LL). Z tego względu domieszki chemiczne mają istotną rolę w kształtowaniu właściwości betonu wykonanego z cementu zawierającego wapień.

EN

The article presents the influence of limestone (LL) on the physical and chemical properties of hardened cement paste. The properties of the Portland limestone cement CEM II/A, B-LL and the Portland composite cements CEM II/A, B-M (S, LL) and CEM II/A, B (V-LL) were analysed. The importance of the w/c-ratio for the level of strength and durability of cement composites made of cement containing limestone (LL) as the main component was emphasized. For this reason, chemical admixtures play an important role in shaping the properties of concrete with cement containing limestone.

8

Renowacja i konserwacja tradycyjnych budynków z lokalnego kamienia wapiennego

Gorączko Marcin, Gorączko Aleksandra

Materiały Budowlane

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2022

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nr 11

74--76

PL

W Kotlinie Kolskiej i w jej otoczeniu do lat 60. XX wieku rozwijało się budownictwo z lokalnego kamienia wapiennego nietypowe dla nizinnej części Polski. Efektem było zaistnienie specyfiki architektonicznej i konstrukcyjnej w tutejszym budownictwie, przede wszystkim wiejskim. Ostatnia dekada przyniosła wyraźne zmniejszenie liczby budynków wykazujących oryginalne regionalne cechy. Jako najistotniejszą przyczynę wskazano prowadzenie prac remontowych i modernizacyjnych z zastosowaniem współczesnych materiałów budowlanych i technologii.

EN

Until the 1960s, the construction of local limestone, unusual for the lowland part of Poland, developed in the Koło Valley and its surroundings. The result was the occurrence of architectural and construction specificity in the local construction, especially in the countryside. The last decade has brought a noticeable reduction in the number of buildings exhibiting original features. The most important reason was renovation and modernization works with the use of modern building materials and technologies without any attempts to maintain their regional character.

9

Predictive modelling of a rapid stratified bed filter for turbidity removal from surface water

Tejada-Tovar Candelaria N., Villabona-Ortíz Ángel, López-Barbosa David

Journal of Water and Land Development

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2022

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no. 53

192--202

EN

The objective of the present work was to evaluate the hydrodynamic behaviour of a stratified bed filtration column consisting of 4 cm of sand and 2 cm of limestone to remove turbidity and measuring the head loss through the filter in several runs. In this study, two types of sand were used as filtering bed material, one fine and one medium. Crushed limestone was also available. These materials were characterized to determine the average particle diameter, porosity, and permeability coefficient. These were respectively 1.7∙10-4 m, 336.96 and 0.68 m∙day-1 for fine sand, 3.3∙10-1 m, 654.24 and 2.59 m∙day-1 for the medium sand and 1.26∙10-3 m, 388.8 and 8.64 m∙day-1 for crushed limestone. Using these materials, hydrodynamic analyses were carried out using clean water under rapid filtration conditions. In these analyses, different filtration rates were determined to be used in each experiment. Once the filtration rates were determined, the filtration analysis was performed with synthetic turbid water prepared at 8 NTU using tap water and bentonite. From the results obtained, a predictive model was developed based on total head losses for the evaluated filter, maintaining the rapid filtration condition. As a result, a turbidity removal efficiency of 97.7% was obtained with a total head loss of 17.8 cm at a filtration rate of 153 m·day-1 . The developed model predicted head loss as a function of operating time, filtration rate, and filter depth to maximise turbidity removal. The model showed excellent prediction accuracy with R2 of 0.9999, which indicates that the model predictions are not biased. It was concluded that, due to the porosity of these materials, a stratified bed of sedimentary rocks has a great potential to be used in surface water filtration processes, which implies that it could be used at the rural community level as a form of water treatment, since the material is a readily available, maintenance is simple and low cost, and installation and operation are effortless.

10

Wpływ mączki ze skorupek jaj kurzych i z wapienia, na właściwości reologiczne zaczynów cementowych

Grzeszczyk Stefania, Kaleta-Jurowska Alina, Jurowski Krystian

Cement Wapno Beton

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2022

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R. 27, nr 6

403--411

PL

Przedstawiono badania wpływu mączki, uzyskanej ze skorupek jaj kurzych oraz z wapienia, na właściwości reologiczne zaczynów cementowych. Mączki dodano do cementu portlandzkiego CEM I 42,5 R, w ilości 30%. Stwierdzono większe granice płynięcia i lepkości plastyczne dla zaczynów z cementów z dodatkiem mączki ze skorupek jaj kurzych, od zaczynów cementowych, z dodatkiem mączki z wapienia. Przyczyną jest wpływ budowy błonki jajka kurzego. Chłonąca wodę i pęczniejąca w zaczynie cementowym błonka, powoduje wzrost lepkości oraz zwiększenie tiksotropii w wyniku łączenia się cząstek, w porównaniu z klasycznym zaczynem oraz zaczynem z dodatkiem mączki z wapienia.

EN

The paper presents the effect of the powders obtained from eggshells and limestone on the rheological properties of cement pastes. Both powders were added to Portland cement CEM I 42.5 R, 30% by mass. The higher yield stress and plastic viscosity of the cement pastes prepared with the addition of eggshell powder, compared to the cement pastes made with limestone powder, were explained by the influence of the eggshell membrane and its chemical structure. The membrane, which absorbs water and expands in the cement paste, is causing an increase in rheological parameters. The membrane, which absorbs water and swells in the cement paste, causes an increase in viscosity and thixotropy compared to the neat cement slurry and slurry with limestone meal added as a result of particle bonding.

11

The use of limestone in historic road surfaces – a case study

Hydzik-Wiśniewska Joanna, Hycnar Elżbieta

Archives of Mining Sciences

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2022

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Vol. 67, no. 3

477--490

EN

The article presents the problem of selecting the correct type of limestone for producing paving stones used to renovate the surface of Mariacki Square in Krakow. Due to using up local limestone deposits, imported limestones began to be used. The first one was a Turkish limestone with the trade name Lotus Beige. Despite substantial physical and mechanical parameters (compressive strength 134 MPa, water absorption 0.26%), after several years of use, the paving stone cracked and, as a result, fell apart into smaller fragments. Hauteville limestone from France has been selected for the following reconstruction of the surface. This limestone in the air-dry state was characterised by even higher parameters, i.e. compressive strength of 157 MPa, flexural strength at 16.9 MPa, Bohme Abrasion test at 15275 mm3, and water absorption at 0.23%. The tests also showed absolute frost resistance and high resistance to thermal shock. Unfortunately, after several years of using the surface of Mariacki Square, cracks and flaking of the rock material have been observed in terms of some paving stones. These cracks appeared within the so-called stylolite seams, which are a natural feature of limestone. Despite a very strict selection of materials, unfortunately, problems with the surface’s durability could not be avoided.

12

Improving the efficiency of fluidized bed comminution of limestone samples

Wysocki D.

Journal of Achievements in Materials and Manufacturing Engineering

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2021

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Vol. 107, nr 1

5--14

EN

Purpose: The aim of the research was to describe the properties and methods of using limestone for desulfurization of flue gases and to analyse the process of fluidized bed comminution and the influence of selected parameters and stand modification on quality of product of fluidized bed comminution. Design/methodology/approach: Tests of the grinding process on the fluidized bed were carried out using a modified fluid bed mill for operational variable parameters and their results were compared with the results received before modification. The modification of the test stand consisted of increasing the height of the grinding chamber, which ensured an increase in the volume of the fluidized layer where the grinding process takes place. Findings: Main parameters that determined the effects of comminution in the analyzed case were: overpressure of working air and the rotor speed of the classifier. The introduction of the modifications of the test stand ensured an increase in the volume of the fluidized layer in which the grinding process takes place. As well as a greater gravitational classification, which caused larger grains to be stopped in the grinding chamber and shift of characteristics of grain compositions towards finer grains. Research limitations/implications: It is assumed that the diameter of sorbent grains used in the fluidized bed can not exceed 6 mm. The granularity of the offered sorbents ranges from 0.1 mm to 1.2 mm. The quality of the desulfurization process depends on the overall granulation of used sorbent grains. Practical implications: Appropriately selected sorbent grains used in wet and dry flue gas desulphurisation plants ensure improved efficiency of the desulphurisation process and lower operating costs of the installation. Originality/value: Thanks to the comminution method used, a sorbent is obtained without impurities and with an increased specific surface, which can be used in fluidized bed boilers.

13

Properties of mortars with Calcium Sulfoaluminate cements with the addition of Portland cement and limestone

Gołaszewski Jacek, Gołaszewska Małgorzata

Archives of Civil Engineering

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2021

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Vol. 67, nr 2

425--435

EN

Calcium Sulfoaluminate cements (CSA) may be an alternative to Portland cements due to their very high early strength and more environmentally friendly production technology, however they are characterized by a short setting time and high cost. A possible solution to these problems is to mix CSA cement with other binders or additives. In order to test this possibility, CSA cement was mixed with Portland cement and limestone in the amount of 10, 20 and 30 wt. %. A hydration heat test was carried out in the first 72 hours after the components were mixed, measured were compressive and flexural strength after 1, 2, 7 and 28 days, and rheological properties, including early shrinkage. A negative interaction between CSA and CEM I 42.5R was observed, leading to deterioration of mechanical properties of the mortars. The study did not indicate a similar negative interaction between CSA cement and limestone.

PL

Potrzeba zmniejszenia śladu węglowego stała się jednym z głównych problemów przemysłu cementowego ze względu na wysoką produkcję dwutlenku węgla w procesie spalania klinkieru portlandzkiego, która wynosi od 0,6 do 0,8 tony CO2 na 1 tonę klinkieru portlandzkiego. Sytuacja ta stwarza zapotrzebowanie na mniej popularne klinkiery, takie jak cement CSA (cement wapniowo siarczanoglinianowy). Cement CSA charakteryzuje się krótkim czasem wiązania, wysoką wytrzymałością początkową i niskim skurczem, a podczas jego produkcji emitowane jest mniej CO2 w porównaniu z klinkierem OPC. Jednakże wysoki koszt cementu CSA zachęca do mieszania CSA z innymi, tańszymi spoiwami lub nieklinkierowymi składnikami głównymi cementu. Celem prezentowanych badań było zatem zbadanie właściwości zapraw z użyciem cementu CSA zmieszanego ze zwykłym cementem portlandzkim CEM I 42,5R (OPC) lub wapieniem w ilości 10, 20 i 30% masy cementowej. Badano następujące właściwości: ciepło hydratacji w pierwszych 72 h od połączenia cementu z wodą, wczesny skurcz zaprawy w pierwszych 24 h, właściwości reologiczne, czyli granicę plastyczności i lepkość plastyczną świeżej zaprawy, a także wytrzymałość na ściskanie i zginanie po 1, 2, 3, 7 i 28 dniach. Zaprawy przygotowano na bazie normowej zaprawy wg EN 196-1, zawierającej 450g cementu, 1350g piasku normowego i o stosunku w/c wynoszącym 0,5. Ze względów technicznych stosunek w/c został zmieniony dla pomiarów reologicznych na 0,6.

14

The effect of porosity on the reactivity of calcium sorbents

Wichliński Michał, Kobyłecki Rafał

Mineralogia

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2020

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Vol. 51, iss. 1

37--45

EN

The current work presents the results of seven sorbent samples investigated with respect to SO2 capture. The sorbents’ reactivity and capacity indexes were determined, and the tests were carried out in accordance with the ‘classical’ procedure for limestone sorbents. The reactivity indexes (RIs) of the tested samples were in the range of 2.57 and 3.55 (mol Ca)/(mol S), while the absolute sorption coefficients as determined by the capacity index (CI) varied between 87.9 and 120.6 (g S)/(kg of sorbent). Porosimetric analysis was also carried out and the specific surface area of the samples was found to be between 0.2 and 1.7 m2 /g. The number of micro-, meso- and macro-pores in individual samples was determined from the corresponding pore size distribution histograms, and the values of sorbent RIs and CIs were correlated with the samples’ total porosity and specific surface.

15

Cementy portlandzkie wieloskładnikowe żużlowo-wapienne (S-LL)

Synowiec Katarzyna, Batog Maciej

Materiały Budowlane

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2020

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nr 10

32--35

PL

Właściwości fizykochemiczne cementów żużlowo-wapiennych są na zbliżonym poziomie do właściwości cementu portlandzkiego żużlowego. Zaobserwowano przy tym korzystny wpływ udziału wapienia w składzie cementu na wytrzymałość na ściskanie zapraw cementowych, szczególnie przy obniżonym współczynniku w/c. W ocenie właściwości betonu szczególną uwagę zwraca efekt doszczelnienia struktury matrycy cementowej, przejawiający się zwiększeniem odporności na wnikanie mediów ciekłych i gazowych w głąb betonu (ograniczenie głębokości penetracji wody pod ciśnieniem oraz przenikalności jonów chlorkowych). Możliwe jest uzyskanie betonów klasy C30/37. Natomiast zapewnienie mrozoodporności betonu z cementów portlandzkich wieloskładnikowych (S-LL) nie jest łatwe do osiągnięcia, pomimo prawidłowego napowietrzenia mieszanki betonowej.

EN

The physicochemical properties of the composite slag-limestone cements are similar to those of the Portland slag cement. Additionally a favorable effect of limestone on the compressive strength of cement mortars was observed, especially at a reduced w/c ratio. While assessing the properties of concrete, particular attention is paid to the effect of sealing the structure of the cement matrix, which is manifested in the increased resistance to media penetration into the concrete (limiting the depth of water penetration under pressure and the permeability of chloride ions). It is possible to obtain concretes of C 30/37 class, while ensuring the frost resistance of concrete frost resistance of concrete with Portland composite cement (S-LL) seems to be quite challenging to achieve despite the proper aeration of concrete.

16

Kopalnia Budy – nowoczesna eksploatacja dolomitu i wapienia z blisko 100-letnią historią wydobycia

Zięba Marcin

Kruszywa : produkcja - transport - zastosowanie

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2020

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Nr 3

24--31

PL

Województwo świętokrzyskie znane jest ze swoich złóż kruszyw. Jednym z wyróżniających się zakładów górniczych jest ten działający od wielu lat w Budach. Tym razem po kopalni oprowadzi nas jej kierownik Marek Zając, który opowie nie tylko o prehistorycznej przeszłości tych terenów, ale także o tym, jakie są plany firmy na przyszłość.

17

The dolomite problem : evidence from 3D modeling, XRD and geochemical data of Zechstein reefs (Upper Permian, Germany)

Blendinger Wolfgang

Geological Quarterly

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2020

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Vol. 64, No. 3

692--710

EN

Three-dimensional modeling of the limestone and dolomite distribution in an Upper Permian (Zechstein) stromatolite-bryozoan reef, ~500 m in diameter and 35 m thick (77 borehole cores, 172 data points), shows that dolomite occurs as laterally and vertically discontinuous intervals. The prevailing mineral phases are near-stoichiometric dolomite and Mg-free calcite (370 XRD and 274 XRF analyses). Both δ13C and δ18O (526 analyses) show a spread of ~10‰ and co-vary with the mineralogy; the heaviest dolomite and calcite δ13C differ by ~1.5‰. Diagenetic modifications caused by flowing meteoric fluids could account for the observed “inverted J” trend of stable and the radiogenic signature of 87Sr/86Sr (23 analyses), but neither vertical nor horizontal gradients occur in the reef modeled. Because the dolomite geometries are incompatible with those predicted by fluid flow models, and the limestone-dolomite difference in δ13C overlaps estimates of isotope fractionation associated with Mg content, the dolomite studied was a depositional Very High Mg Calcite recrystallized to dolomite in a semi-closed diagenetic system rather than a Low Mg Calcite transformed by a dolomitization process. The isotope pattern suggests biogenic fractionation and/or loss of heavy stable C and O and light Sr isotopes during diagenesis.

18

Susceptibility of selected aggregates from sedimentary rocks to alkali-aggregate reaction

Glinicki Michał A., Jóźwiak-Niedźwiedzka Daria, Antolik Aneta, Dziedzic Kinga, Gibas Karolina

Roads and Bridges - Drogi i Mosty

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2019

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Vol. 18, no. 1

5--24

PL

W pracy przedstawiono wyniki badań reaktywności krajowych kruszyw z wybranych, litych skał osadowych przy wykorzystaniu nowych metod badawczych wdrożonych w dokumentach technicznych Generalnej Dyrekcji Dróg Krajowych i Autostrad (GDDKiA), zgodnych z metodami RILEM i ASTM. Zakres badań obejmował kruszywa grube łamane o potencjalnej przydatności do wykonania wytrzymałego i trwałego betonu, wyprodukowane ze skał wapienia, dolomitu, piaskowca i szarogłazu. W składzie mineralnym kruszyw z wapieni i dolomitu nie stwierdzono obecności reaktywnych form kwarcu; w ziarnach kruszywa z szarogłazów i piaskowca występował kwarc mikro- i kryptokrystaliczny. Na podstawie wydłużenia próbek określono następujące kategorie reaktywności wybranych krajowych kruszyw ze skał osadowych: R0, R1 i R2. Zaobserwowano występowanie żelu krzemianu sodowo-potasowo-wapniowego o składzie charakterystycznym dla produktów reakcji alkalia-kruszywo, zgodnym z danymi literaturowymi. Uzyskano spójną ocenę reaktywności kruszyw.

EN

The paper presents the results of investigations into the reactivity of domestic aggregates produced from selected sedimentary rocks, carried out using the new testing methods, consistent with the RILEM and ASTM methods, implemented by GDDKiA (Polish General Directorate for National Roads and Motorways) documents. The range of the investigations covered coarse crushed aggregates produced from limestone, dolomite, sandstone and greywacke rocks, potentially suitable for making strong and durable concrete. No reactive forms of quartz were found in the mineralogical composition of the limestone aggregates and the dolomite aggregates. Micro- and cryptocrystalline quartz occurred in the particles of the greywacke aggregates and the sandstone aggregates. On the basis of the expansion of mortar and concrete specimens the aggregates produced from the sedimentary rocks were classified into the reactivity categories: R0, R1 and R2. A sodium-potassium-calcium silicate gel, whose composition (consistent with that reported in the literature) was characteristic of the alkali-silica reaction products, was found. The investigations resulted in a consistent assessment of the reactivity of the aggregates.

19

Wapienie z Czatkowic i różnorodność ich zastosowania

Kuć Paweł

Przegląd Geologiczny

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2019

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Vol. 67, nr 1

56--59

EN

The aimof this article is to show the directions of using limestone from the Czatkowice mineral deposit (near Kraków, southern Poland). Because of the high purity of this raw material, it is widely used in many industries. The limestones found application in production of mineral sorbents and limestone powder and sand, crushed aggregates and in the past these rocks were applied as flux for metallurgy. In recent years different color and textural varieties of Czatkowice limestone cut by veined calcite have also been employed as building and architectural material, which is best exemplified by the new church in Krzeszowice.

20

Strumień ciepła transportowany do dysocjowanej termicznie bryły wapienia w otoczeniu ścian i gazu o zmiennej zawartości CO2 - Część II: Obliczenia

Lech Ryszard

Materiały Ceramiczne

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2019

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T. 71, nr 2

107--116

PL

Na podstawie wyników badań dysocjacji termicznej dużych próbek wapienia prowadzonej w zamkniętym układzie ścian wymieniających ciepło i wypełnionym mieszaniną gazową zawierajacą CO2 wykazano, że szybkość dysocjacji termicznej próbek zależy od zawartości CO2 w mieszaninie gazowej podawanej do komory grzewczej. Coraz wolniejsze tempo spadku średniej szybkości dysocjacji termicznej powodowane jest wzrostem stężenia CO2 w mieszaninie gazowej, w której kalcynowana jest próbka. Wiąże się to ze wzrostem wartości ciepła właściwego mieszaniny gazowej otaczającej próbkę, tym samym powodując zwiększenie wartości strumienia ciepła wynoszonego z komory grzewczej wraz z mieszaniną gazową opuszczającą komorę grzewczą. Wykazano, że dodatek CO2 do mieszaniny gazowej otaczającej kalcynowaną próbkę powoduje znaczący spadek wartości strumienia ciepła wnikającego do próbki ze względu na obniżkę wartości konwekcyjnego współczynnika wnikania ciepła oraz wzrost emisyjności mieszaniny gazowej. Wskazania termopary z odsłoniętą spoiną, umieszczoną między ścianami próbki i komory grzewczej, właściwie oddają zmiany temperatury w komorze grzewczej wywołane zmienną zawartością CO2 w mieszaninie gazowej.

EN

Based on the results of thermal dissociation tests for large limestone samples carried out in a closed system of heat exchanging walls and filled with a gas mixture containing CO2, it was shown that the rate of thermal dissociation of samples depends on the CO2 content in the gas mixture fed into the heating chamber. The slower rate of decline in the average rate of thermal dissociation is caused by the increase in CO2 concentration in the gas mixture in which the sample is calcined. This is associated with an increase in the specific heat value of the gas mixture surrounding the sample, thereby increasing the heat flux value from the heating chamber together with the gas mixture leaving the heating chamber. It has been shown that the addition of CO2 to the gas mixture surrounding the calcined sample causes a significant decrease in the value of the heat flux transported to the sample due to a decrease in the convective heat transfer coefficient and an increase in the emissivity of the gas mixture. Indications of the thermocouple with the exposed junction, placed between the walls of the sample and the heating chamber, properly reflect the temperature changes in the heating chamber caused by the variable content of CO2 in the gas mixture.