Search Results (76)

Carbonation–calcination looping using CaO-based natural sorbents such as limestone is a promising technology for the capture of CO₂ from fossil fuel-based power plants. In this study, the CO₂ capture capacities of Buipe, Oterpkolu, and Nauli limestones from quarries in Ghana were measured in a laboratory-scale micro-fluidized bed reactor through multiple carbonation–calcination cycles. The changes in CO₂ capture capacity and conversion with the number of cycles mostly correlated with the changes in the physico-chemical properties: Capture capacity dropped from >60% to <15% after 15 cycles and the surface area dropped to below 5 m² g⁻¹ from as much as 20 m² g⁻¹ (for the Oterkpolu). The pore volume of the Nauli limestone was essentially invariant with the number of cycles while it increased for the Buipe limestone, and initially increased and then dropped for the Oterpkolu limestone. This decrease was likely due to sintering and a reduction in the number of micropores. The unusual increase in pore volume after multiple cycles was due to the formation of mesopores with smaller pore diameters. Full article

Quarrying is a key driver in economic growth but also poses significant environmental impacts, particularly on groundwater resources. With approximately 4000 active quarries and diverse hydrological and hydrogeological conditions across Italy, the need for effective regulations that ensure both sustainable extraction and groundwater protection is paramount. This study analyzed the European directives, national legislation, and regional quarrying plans governing extractive activities, with a particular focus on groundwater protection. By analyzing the Italian quarries and their main hydrogeological characteristics, the most prevalent hydrogeological scenarios associated with quarrying activities across the country have been identified. The findings reveal significant gaps in the current regulatory framework, characterized by fragmentation and inconsistency across regions. Critical concerns across the quarry lifecycle (planning, excavation, and reclamation) are not comprehensively addressed, and mandatory monitoring and safeguard requirements are lacking. A more structured regulatory approach could incorporate key parameters identified in this study, particularly quarry size and groundwater level depth relative to the excavation plan. Additionally, hydrogeological vulnerability must be considered to guide risk assessment, particularly for alluvial and limestone hydrogeological complexes, which host a substantial number of Italian quarries and require stricter safeguards due to their high susceptibility to contamination and hydrodynamic alterations. Full article

This study presents a chemical and mineralogical analysis of stone samples from Jošanica quarry collected from three different locations—Field A, Field B, and Field C. Mineralogical analyses were conducted using XRD analysis. The analyses showed that calcite was the dominant mineral in most of the samples, while dolomite was significantly present in some of the samples. Chemical analysis revealed that calcium was dominant in samples 2 (Field B), 3a, and 3b (Field C), with only negligible amounts of magnesium. In contrast, samples 1a, 1b, and 1c (Field A) contained a significant amount of magnesium. Based on the MgCO₃ content, the amount of dolomite in the stone samples was calculated. The content of CaCO₃ in its bound form in dolomite was lower than that in the stone samples, indicating that CaCO₃ was present in another form. According to the dolomite content, samples 1a, 1b, and 1c (Field A) are classified as limestone–dolomite, while samples 2 (Field B), 3a, and 3b (Field C) are classified as limestone due to their high calcium carbonate content. The results of a mineralogical analysis confirmed the results of the chemical analysis. Full article

The disposal and recycling of industrial by-products such as marble and limestone powders pose pressing environmental challenges due to the substantial amounts of waste generated annually by marble processing plants and limestone quarries. The integration of these by-products into concrete production is justified by their widespread availability and the potential to alleviate the environmental burden. This study used a statistical mixture design approach to systematically assess the effects of limestone and marble powders, with varying fineness levels, as partial cement replacements (up to 17%) on the rheological and mechanical properties of self-compacting concrete (SCC). The experimental findings revealed that the density of the SCC mixtures ranged from 2475 to 2487 kg/m³. Mixtures incorporating limestone powder exhibited superior flowability, achieving a slump flow of up to 69 cm, an 8% improvement compared to those containing marble powder. However, marble powder with a specific surface area of 330 m²/kg demonstrated significant improvements in compressive and tensile strengths, with increases of 18%. Statistical analysis using analysis of variance (ANOVA) validated the reliability of the predictive models developed, which demonstrated coefficients of determination (R²) that exceeded 0.94 and p-values below 0.05. These models enable precise predictions of critical performance metrics, including density, slump flow, box flow, compressive strength, and tensile strength, thus reducing the need for extensive experimental procedures. Full article

In contrast to several types of marbles used in antiquity, where different data collections do exist, similar approaches for provenance analysis are not available for limestones. In general, limestones are characterised visually and by the examination of sedimentological parameters. The usual microscopic investigation of limestones and the characterisation of limestone artefacts are often impossible because of the large samples necessary for these investigations. It is demonstrated in this paper that for the provenance analysis of limestone, the same established methods used for assigning marbles to their origin can also be successfully used in the case of limestone. We investigated a series of Roman quarries (three different quarry regions) in the north of the Haemus Mountain Range in the region of Marcianopolis and Nicopolis ad Istrum with the aim of establishing a first database (isotope analyses and trace element analyses) to correlate limestone artefacts. All in all, 42 quarry samples from the locations Marciana, Samovodene and Koevtsi were investigated. Fifteen artefacts made of limestone were analysed. Two samples from Marcianopolis were assigned to the Marciana quarry, and seven artefacts from Nicopolis ad Istrum originate from the quarries of Samovodene. For six more samples from Nicopolis ad Istrum, no match to one of the sampled and investigated quarries was found; thus, the existence of one or more quarries in the area is presumed. An extension of the database and the investigation of further limestone quarries in the area certainly will compensate for this deficiency. Full article

This paper presents the results of the analyses conducted on 46 stone samples collected from Roman buildings in Oderzo, a small town located in the heart of the eastern Venetian plain (29 samples), and from architectural artifacts preserved at the local archeological museum “Eno Bellis” (17 samples). The aim of this study is to identify the types and provenance of the stones used for architectural purposes in Roman times in the city of Oderzo (ancient Opitergium). All the materials were petrographically characterized using a multi-analytical approach, including polarized light optical microscopy (PLM). Moreover, volcanic rock samples were analyzed via X-ray fluorescence (XRF) and quantitative phase analysis via X-Ray powder diffraction (QPA-XRPD) to obtain more detailed mineralogical and geochemical characterizations. These methods proved valuable for better determining the provenance of the materials. The results allowed us to determine the quarrying areas that Opitergium mostly relied upon in antiquity for sourcing building materials, as well as the stone trade networks in which the city was integrated. Preliminary findings indicate a higher frequency of stones sourced from outcrops along the Prealpine Arc of north-eastern Italy and Istria, including Aurisina limestone (Trieste Karst), and micritic limestones possibly quarried in the Istrian peninsula for architectural artifacts. Conversely, lithotypes from north-western Prealps appear to have been used less frequently. The volcanic rock samples were entirely sourced from various quarry sites in the Euganean Volcanic District in the Veneto region. Full article

Limestone Calcined Clay Cement (LC³) has become a highlighted research topic over the past decade. Through various research, LC³ demonstrated the capability to supplement portions of cement, highlighting the possibility to decrease CO₂ emissions due to the low calcination temperatures and low levels of CO₂ released from the material during calcination. At this stage, there is no research into the feasibility of LC³ in any parts of Australia, limited research in finding clay, and incomplete research understanding how low calcination temperatures affect the compressive strength. The results show the feasibility of LC³, where we demonstrated the feasibility of a low calcination temperature of 650 °C and found that various overburden waste clays (clay in quarries and mines that are not needed) across the East Coast of Australia produced comparable compressive strength results to conventional Portland cement-based mixes. The results also indicate that optimising the particle size distribution of the calcined clay enhanced both the workability and compressive strength of the mortars. Full article

The presented paper analyzes the impact of limestone dust accumulation on photovoltaic (PV) panel performance, focusing on the specific surrounding conditions near quarries. The results from the performed field measurements show that high concentrations of limestone dust accumulate significantly faster in these areas, and a hard layer is formed in the presence of moisture. This layer of dust is resistant to removal, even in moderate precipitation and winds with speeds between 6 and 9 m/s, making it a significant problem for the long-term performance of the systems. The analysis revealed that the lack of systematic cleaning of the panels leads to a drop in efficiency of over 20%, with this loss pointedly limiting the return on investment. This study highlights the need for innovative maintenance approaches, such as regular cleaning, use of special coatings and adapting designs to specific environmental conditions. This is essential for the development of strategies to manage, maintain and improve PV systems in areas with high levels of dust pollution. Full article

Limestone has always been widely used in various sectors, thus having significant economic and environmental impacts. The quarrying process is, on the one hand, essential, but on the other, harmful to the environment and people’s health, therefore, the challenge is finding a balance. This review explores the multifaceted nature of limestone, a sedimentary rock predominantly composed of calcium carbonate. The formation of limestone, along with its various types and global occurrence, is discussed to provide a basic understanding. The diverse applications of limestone range from historical uses in ancient monuments to contemporary roles in cement production, plasticized polyvinyl chloride (PVC), and soda–lime glass. The discussion extends to post-mining solutions, showcasing successful rehabilitation and innovative repurposing of former quarries into useful infrastructures, wildlife habitats, and cultural spaces. This article draws attention to the importance of sustainable practices and technological developments to balance resource use with environmental conservation. Ultimately, it emphasizes the need for responsible limestone quarrying and proactive rehabilitation strategies to ensure that no permanent ecological problems will occur. Full article

Agricultural industrial waste has demonstrated potential as a soil acidity corrector and fertilizer, in addition to reducing environmental impacts caused by inadequate waste disposal. Ornamental rock waste is a sustainable alternative as it contains essential elements for plant growth. (1) Background: this study aims to evaluate using marble waste in SENA and the Gallo Crudo Quarry in Colombia as an acidity mitigator in soils cultivated with maize (Zea mays) in a greenhouse. (2) Method: four treatments were applied: T0: without marble dust—MD; three doses of MD (T1: 1.1 Mg of MD ha⁻¹; T2: 2.2 Mg of MD ha⁻¹; and T3: 3.3 Mg of MD ha⁻¹). After 70 days, soil fertility analyses were carried out. (3) Results: The results show that the chemical properties of the soil improved with all treatments, mainly with T2, influencing the calcium (Ca), carbon (C), sulfur (S), and magnesium (Mg) contents. MD’s pH and Al + H values were higher than conventional treatments. The T2 treatment reduced soil acidity from 0.2 cmol + kg⁻¹ to 0.0 cmol + kg⁻¹ and increased pH to 7.91 compared to the control (5.4). The maize plants in the T2 treatment developed better, indicating that the dose of 2.2 Mg of MD ha⁻¹ can replace commercial limestone. (4) Conclusions: This agroecological technique is an innovative alternative in Colombia, replicable in areas with ornamental rock reserves, benefiting the agricultural economy and contributing to target the Sustainable Development Goals, which promote sustainability, responsible management of natural resources, and a reduction in environmental impacts. Full article

Very large quantities of stone waste sludge are disposed in exhausted quarries and have a very low reuse rate to date. The paper considers the possibility of using these types of industrial waste in partial substitution of natural aggregates for the production of lime-based plasters. Traditional materials based on lime, the only material with a carbon neutrality life cycle, have considerable potential for use as components of green materials for plastering and finishing building surfaces in both new construction and historic heritage conservation. The paper presents the preliminary results of a research activity aimed at developing pre-packaged products based on Traditional Lime Putty (TLP) by partially replacing natural aggregates with Stone Waste Sludge (SWS), with a low rate of recovery from the Apricena limestone production district in Apulia. The mineralogical and chemical analysis carried out using XRD (X-Ray Diffraction), TG-DTA (Thermo Gravimetry-Differential Thermal Analysis), and hydrochloric acid attack test showed that the SWS consisted of 98.4 % CaCO₃ by mass. The particle sizes measured by laser diffraction technique are below 22.5 μm for the 92% mass of the sample. The high fineness of the stone waste was confirmed by the Blaine-specific surface method, which equals to 9273.79 cm²/gr. The behavior of three fresh mixtures for prepacked coarse plaster, fine plaster, and finishing plaster with 12.90%, 17.94%, and 18.90 by mass of SWS, respectively, was evaluated by spreading test and applicability tests on a perforated ceramic slab. The finishing plaster has the highest consistency value of 235 mm, while the fine plaster and the coarse plaster have values of 205 mm and 155 mm, respectively. The coarse plaster is suitable for use as base plaster (arriccio) or second layer rendering (tonachino) up to a thickness of approximately 1 cm. Both the fine plaster and finishing plasters can be used for the surfaces finishing with the application of layers of a few millimeters thick. Full article

In addition to the surrounding climatic environment, the intrinsic characteristics of the stones used in construction are a critical factor to understand a building’s conservation state and define the necessary planning and conservation management activities. The use of environmentally susceptible stones, such as carbonate stones, in heritage buildings can be especially problematic. The present investigation presents an overview of past research and contributes to identifying the types of carbonate stones used over time in Coimbra’s Old Cathedral in Portugal, which was classified as a National Monument and integrated into the Coimbra World Heritage site by UNESCO. Our mineralogical and chemical analyses revealed the use of carbonate stones from different quarries (Coimbra region), including Ançã limestone and dolostone (Porta Especiosa portal), Portunhos limestone and Outil limestone (in the perimeter of windows), and marlstones and Outil limestone (side facades). These stones, which were installed at various times during the construction and alteration of the monument, represent a great challenge for conservation planning due to their intrinsic vulnerability to adverse environmental conditions and pollution. Full article

In this study, the feasibility of using ceramic wastes in the production of blended cement was evaluated by substituting limestone with ceramic waste at the percentages of 5, 10, 15, 20, and 28% before the milling stage. The chemical, physical, and mechanical properties of the cements were determined according to relevant standards, and the results were compared. The chemical analysis showed that the SiO₂ content of the cements increased with higher ceramic waste substitution percentages, while the CaCO₃ content decreased. The grindability of cements decreased with increased ceramic waste ratios, slightly reducing the Blaine specific surface area values. The water consistency for the cements was set at 28%, and all the cements met the standard limitations. The spread diameters for all types of cements were similar and practically usable in terms of workability. The cements containing ceramic waste either maintained or extended the setting time. All cements with ceramic waste exhibited higher flexural and compressive strength compared to the reference cement. The highest flexural strengths were achieved with a 28% ceramic waste substitution ratio across all curing ages. Regarding compressive strengths, all cements exhibited higher compressive strength than 10 MPa at 2 days and 32.5 MPa at 28 days, classifying them as 32.5 R-type blended cements. When the medium- (56–90 days) and long-term (365 days) compressive strengths were compared, the highest strength values were obtained from the cement with a 28% ceramic waste substitution. Although limestone-blended cement is emerging as a promising alternative to traditional Portland cement, these types of cement still contribute to environmental degradation due to the extraction of natural limestone resources through quarrying. This study showed that blended cements can be produced using ceramic waste, providing a more sustainable and environmentally friendly solution for the construction industry. Full article

Geological structures significantly influence mining-induced deformations in open-pit mines, with their variations and interactions adding complexity to the excavation process and introducing uncertainties in deformation outcomes. This study utilized numerical simulations to analyze the impact of weak rock zones in a specific open-pit limestone quarry in Japan on mining-induced deformation. The simulation results were both qualitatively and quantitatively validated against field measurements, enhancing the reliability of the findings. Subsequently, four conceptual models were developed based on the characteristics of the quarry to investigate the mechanisms by which weak rock zones affect rock slope deformations. Our analyses demonstrated that slip deformation occurred exclusively when two weak rock zones were connected. This deformation was associated not only with shear failure in the upper weak rock zone but also with the contraction and bending of the lower weak rock zone. Furthermore, the simulation results were consistent with field data and supported by the conceptual models, confirming that the proposed sliding mechanisms can effectively explain the observed deformation behaviors. The insights gained from these models provide valuable references for managing similar geological challenges in other open-pit mines. Full article

This study presents an analysis of the influence of weather conditions on the performance of a multicrystalline silicon photovoltaic module, which operates under constant resistive load and is situated near a limestone quarry. The quarry is a significant source of dust, and hence the focus of the study is on the weather factors influencing the presence of soiling on the module’s surface. The analysis encompasses a three-week period, during which the global horizontal irradiance and wind speed were recorded at 10-min intervals by an on-site weather station. The current, voltage, and back temperature of the module were also measured. Supplementary weather data were obtained from the Copernicus Atmosphere Monitoring Service and the NASA POWER databases. The primary objective is to assess whether any influence of the observed weather conditions on the presence of soiling can be inferred from the recorded data. The contribution is in part intended to test how different techniques can be used to extract useful information on the weather-related effects from somewhat limited data, assembled from various sources, while dealing with the underlying uncertainties. The analysis indicates a persistent deterioration of the module’s performance because of soiling and its subsequent improvement due to a favourable weather event. Full article