Oil Shale Ash Research Articles

Sequential Extraction Procedure for Elemental Speciation in Jordanian Oil Shale Ash

Sequential Extraction Procedure for Elemental Speciation in Jordanian Oil Shale Ash

The adsorption performance of high crystallinity Na-p zeolites prepared from oil shale ash for the waste water treatment

ABSTRACTS The Na-p type zeolite has been prepared by the alkali fusion hydrothermal synthesis method using the pure oil shale ash (OSA) and mixture of OSA and coal fly ash (CFA) as raw materials, which was used for adsorption of methylene blue (MB). The XRD spectra of zeolite synthesized from pure oil shale residue under different conditions indicated that the optimal experimental conditions were determined as follows: acid leaching concentration of 10%, sodium hydroxide dosage of 7 g, crystallization temperature of 130°C, and crystallization time of 12 h. Under the same conditions, zeolite was synthesized using the mixture of OSA and CFA, and its properties were characterized using XRD, SEM, and BET techniques. The results showed that the specific surface area and crystallinity of the zeolite prepared from the mixture were 59.6 m2/g and 86.32%, respectively, which were higher than that of pure OSA (20.6 m2/g and 64.07%). When 0.05 g of zeolite was added to the 35 mg/L MB solution and adsorbed for 180 min, the removal rates of MB by pure OSA, single-source zeolite and zeolite prepared from the mixture were 27.6%, 83.4%, and 99.2%, respectively. The adjusted R square verified that the pseudo-second-order kinetics and Langmuir isotherm model were the best fitting models. The maximum adsorption capacity (Qmax) of zeolite prepared from the mixture for MB was 55.5 mg/g. The above results proved that the novel material prepared in this study could be a potential effective wastewater treatment material.

Ash Treatment Promotes the Revegetation of Abandoned Extracted Peatlands

Treating peat with nutrient-rich ash significantly increases the content of different nutrients in the substrate. Such ash treatment promotes the revegetation of abandoned extracted peatlands. The aim of this study is to analyze the effect of wood ash (WA15 = 15 t ha−1 and WA10 = 10 t ha−1), oil shale ash (OSA8 = 8 t ha−1), and a mixture of wood ash and oil shale ash (WA10 + OSA8) on the revegetation (vascular plants and bryophytes) of the Puhatu abandoned extracted peatland in NE Estonia. The following results were obtained: (1) The MRPP tests indicate that there are compositional differences between the treatments. (2) Altogether, 23 vascular plant and 3 bryophyte species were recorded in the treatment areas. (3) Nine years after these ash treatments, the highest mean vascular plant species richness was recorded for WA15 (3.8 ± 0.3) and the lowest for OSA8 (2.0 ± 0.3). (4) A greater number of vascular plant species was observed in the WA15 area. (5) Mixed ash and wood ash had a significant effect on the amount of biomass in vascular plants. Treating with either wood ash or a mixture of ash ensured the rapid formation of vascular plants and bryophyte layers, contributing to the restoration of the abandoned peatland ecosystem.

Improved concrete via upgraded oil shale ash

Improved concrete via upgraded oil shale ash

Investigating the Influence of Oil Shale Ash and Basalt Composite Fibres on the Interfacial Transition Zone in Concrete

Investigating the Influence of Oil Shale Ash and Basalt Composite Fibres on the Interfacial Transition Zone in Concrete

Proportioning of Oil Shale Ash for Sustainable 3D Printable Mortars

To achieve optimal strength and printability, mortars used in 3D printing typically contain high proportions of cement and other fine-grained powders. Consequently, the majority of mixtures used in 3D printing have high carbon footprint. Hence, there arises a critical need to study alternative supplementary cementitious materials aimed at reducing the environmental impact of mortars used in 3D printing. The use of oil shale ash as a partial substitute for cement not only addresses this issue but also presents an opportunity to repurpose waste from power plants in the Baltic states, where oil shale is intensively utilized.In this study, the influence on mechanical properties and durability of cement-based mortars was evaluated by substituting cement with oil shale ash in varying quantities. Specifically, 0% to 40% of cement mass was replaced with oil shale ash. Life cycle assessment (LCA) was performed for each mixture. By analyzing the material properties alongside the environmental impact for each mixture, the optimal percentage of substitute was determined.For the determination of the mechanical properties of each mixture, compressive and flexural strength tests were conducted on 3D printed samples in various directions, as well as on cast samples. To assess the durability of each mixture, freeze-thaw tests were performed on both 3D printed and cast samples.From the obtained results, we developed an algorithm that chooses the optimal mixture proportioning. Depending on material performance requirements set in the beginning, this algorithm gives the exact proportions of oil-shale ash and cement for the mixture, by taking into account both desired material properties and carbon dioxide emissions. As a result, an environmentally friendly cement-based mixture is obtained without losing the desired properties. By using this algorithm, it is possible to create a mortar with properties comparable to concrete with strength class C30/37 while reducing carbon emissions by 15% to 30%.

Study on the effect of oil shale ash on potassium retention characteristics during pyrolysis of corn stalk

In a multi-station fast pyrolysis reactor, the influence of oil shale ash on the potassium retention characteristics of corn stalk under different pyrolysis conditions was investigated in the study. The influence of oil shale ash on the potassium migration process during the pyrolysis of corn stalk was elucidated by analyzing changes in the composition and concentration of potassium and other minerals in the pyrolysis semi-coke of corn stalk. This analysis was conducted using inductively coupled plasma emission spectroscopy (ICP-AES), X-ray diffraction (XRD), and complemented by thermodynamic simulation. The findings demonstrate that oil shale ash could fix potassium in corn stalk, and the potassium retention rate peaked when the oil shale ash additive amount reached to 10 %. This is because the silica-aluminum compounds in the oil shale ash reacts with potassium salts in a semi-molten state to produce KAl2Si3AlO10(OH)2, KAlSi3O8, and KAlSi2O6.When the amount of oil shale ash added is increased to 15 %, KAlSi3O8 and KAlSi2O6 in the semi-coke would continue to react with Al2O3 and SiO2, converting to KAl2Si3AlO10(OH)2. Thermodynamic simulation results indicate that the alkali metal potassium in corn stalk semi-coke mainly existed in potassium metasilicate, potassium feldspar, and leucogranite. In order to enhance potassium fixation in corn stalk, the addition of oil shale ash would promote the transformation of potassium-solidifying minerals from potassium metasilicate to potassium feldspar and leucite in the semi-coke.

Study on physical and mechanical properties of oil shale ash–based green mining filling materials

Study on physical and mechanical properties of oil shale ash–based green mining filling materials

Reviewing the enhancement of expansive soil through different waste material blending

This review paper examines the efficacy of blending various materials for the enhancement of expansive soil behavior. Expansive soils, characterized by volumetric changes in response to moisture fluctuations, present significant challenges in engineering projects. The review explores the utilization of waste additives such as quarry dust, sawdust ash, glass powder, stone powder, marble dust, Lime and Polypropylene Fiber, plastic waste strips and waste brick powder Oil Shale Ash, cement kiln dust as well as innovative solutions including organic compounds and nano-materials. The effectiveness of each material blend in mitigating issues such as swelling, shrinkage, and cracking is analyzed. The study underscores the importance of material selection and optimal blending techniques in achieving desired improvements in soil properties. Additionally, the paper highlights the need for continued research and innovation to develop sustainable solutions for managing expansive soils in construction and geotechnical engineering endeavors.

Utilizing calcined and raw fly oil shale ash in the carbonation process of OPC cement-paste and mortar

This study investigates how carbon dioxide (CO2) curing interacts with raw and calcined fly oil shale ash (FOSA) in ordinary Portland cement paste and mortar (OPC), providing information on previously overlooked synergistic effects of CO2 curing and FOSA calcination. Specimens exposed to CO2 curing followed by water curing were compared to those continuously cured in water. The results reveal that samples containing calcined FOSA as a binder increased compressive strength by up to 200% during the curing stages compared to water-cured samples. Microstructural investigations show that calcium carbonate crystals and other hydration products form, which enhance material properties. The substitution of cement with FOSA results in a reduction in porosity regardless of the curing technique used; however, this issue is efficiently managed by CO2 curing. Higher pH values can be measured from raw FOSA samples, and higher calcination temperatures can result in slightly higher pH values, making the phenolphthalein indicator approach less accurate in detecting carbonation. The application of raw and calcined FOSA as a cement substitute gives long-term benefits while also contributing to environmental awareness in the construction sector.

Dinamika pHKCl u Umbric Albeluvisol Abruptic melioransima različite hemijske prirode

In the paper, changes of pH value during 20 days of soil interaction with the solution have been traced. Differences in the reaction rate using ameliorants of different chemical nature for liming have been established. It was revealed that the ameliorative effect of using materials of silicate nature in the experiment was lower than that of carbonate nature. According to the effect all ameliorants used in the experiment can be arranged in the following descending order: dolomite flour (DF), crushed stone sieve (CSS) > conversion chalk (CC), dolomitized limestone flour (DLF) > blast furnace slag (BFS) > oil shale ash (OSA). For all lime fertilizers empirical models of pHKCL value change over the whole experimental interval were developed. Clustering of separate variants of the experiment, produced by different ameliorants on their influence on the index rNKCL on the whole interval of study was carried out.

Tracing rare earth elements in oil shale ash

Tracing rare earth elements in oil shale ash

Assessing shielding material Performance: Benchmarking of Monte Carlo codes for oil shale and Basalt-Boron fiber concretes

Cement-based concretes are commonly used for managing radioactive waste due to their low cost and radiation shielding properties. However, the potential of using oil shale ash as an additive in waste packaging material has been overlooked. This study focuses on benchmarking and developing a Monte Carlo based modeling methodology using multiple transport codes (MCNP, SERPENT, SCALE, OpenMC, and EGSnrc) to assess the effects of these additives on the gamma and neutron shielding properties of concrete. The cross-code comparison showed that all transport codes are in excellent agreement with each other. Investigations into oil shale ash demonstrated similar properties to fly ash. The addition of oil shale ash had a negligible effect on low-level waste (LLW) gamma shielding properties and a minor negative effect on neutron shielding properties. The addition of basalt-boron fibers indicated a minor negative effect on LLW gamma shielding properties but a significant positive effect on neutron shielding properties. The presence of basalt-boron fibers considerably decreased the photon flux resulting from the activation of concrete. In conclusion, this study offers valuable insights into utilizing radiation transport codes to analyze the interactions between radiation particles and innovative concrete additives.

Engineering properties and mechanical behaviour of problematic soil stabilized by bituminous oil shale ash

This paper investigates the viability of stabilizing expansive brown clays in the Northern region of Jordan using a local bituminous oil shale ash from El-Lajjun, Jordan. A comprehensive experimental programme was designed to i. examine the impact of oil shale ash dose by weight on the strength gain. ii. Evaluate oil shale ash stabilized clays' consolidation and volume change behaviour during loading and unloading. Results revealed that adding 20 % bituminous OSA remarkably improved expansive brown clays' engineering properties and mechanical behaviour. An increase of 140 % in the unconfined compressive strength and a reduction of 19.3 % in the permeability coefficient was obtained at 20 % OSA. Also, the Unconfined Compressive Strength tests revealed that the strength of OSA-treated expansive clays is significantly affected by the curing time. Increases of 35.1 % and 65.7 % in the unconfined compressive strength were achieved after 7 days and 21 days of curing, respectively. Furthermore, the addition of OSA showed an effect on compressibility behaviour, reducing settlement. Regarding the consolidation parameters, the inclusion of 20 % OSA reduced the compression index (Cc) and swelling index (Cs) by 42.67 % and 72.6 %, respectively.

Effect of using Oil Shale Ash on geotechnical properties of cement-stabilized expansive soil for pavement applications

Expansive soil is considered an engineering problem that may cause cracks and distresses in structures and roads. Due to its swelling potential and low unconfined strength, expansive soil causes failures in structures and leads to financial losses. Oil Shale Ash “OSA” is the byproduct of the combustion of the oil shale rock to produce electricity. Instead of dumping OSA materials into landfills, which has several negative environmental implications and cost burdens, utilizing these materials as building materials might alleviate the environmental concerns caused by their disposal. This research investigates the possibility of experimentally using the by-products Oil Shale Ash (OSA) and Portland Cement (PC) to enhance the geotechnical properties of problematic expansive soil. OSA and cement have been added to the soil, where OSA is used in four percentages by dry weight of soil (10%, 20%, 25%, 30%), and cement is used in three percentages (2%, 4%, 6%). A laboratory test program was implemented, including Atterberg limits, compaction test, unconfined compressive strength test (UCS), swell test, linear shrinkage test, and California Bearing Ratio (CBR) test. The results showed that OSA and cement have reduced the expansive natural soil's swelling potential, plasticity index, and linear shrinkage. Also, the UCS and CBR values of treated soil have improved significantly. Pavement analyses demonstrated that OSA-cement-stabilized soil could be a suitable stabilization agent for the subgrade and base layers in constructing pavements.

Evolution of Durability and Mechanical Behaviour of Mud Mortar Stabilized with Oil Shale Ash, Lime, and Cement

The investigation into earthen construction technologies and materials is now acknowledged as a crucial area requiring further research. Earthen mortars are prevalent in both modern and traditional construction due to the abundance of earth material, their favorable thermal properties, and their low embodied energy. The objective of this study is to support the use of natural materials collected from north Jordan to enhance the mechanical properties and durability of mud mortar. The local soil was stabilized using Oil Shale Ash (OSA), Ordinary Portland Cement (OPC), and lime for producing mud mortar. Particle size analysis, plastic limit, liquid limit, XRD, and XRF were applied to assess the geotechnical characterization and mineral composition of the earthen stabilizers and local soil. In order to examine the mechanical properties (specifically compressive strength) and durability characteristics (such as water absorption and shrinkage) of mud mortar, a total of 8 mixtures were prepared. One of these mixtures served as a control, while the others were created by substituting soil with varying proportions of OSA, cement, and lime. The results show that the mud mortar contained 10% OSA and 10% cement, which exhibited the highest compressive strength. Moreover, an increase in the proportion of OSA in the soil led to a decrease in absorption and linear shrinkage, indicating that OSA is an effective stabilizing agent for mud mortar. Doi: 10.28991/CEJ-2023-09-09-06 Full Text: PDF

Bridging Law Application to Fracture of Fiber Concrete Containing Oil Shale Ash

Concrete is a widely used material in various industries, including hazardous waste management. At the same time, its production creates a significant carbon footprint. Therefore, intensive research is being conducted to create more eco-friendly concrete, for example, partially replacing cement with by-products such as oil shale ash (OSA) or improving properties by adding dispersed fibers such as basalt fibers (BFs). The article consists of experimental testing of nine types of concrete and the modeling of crack propagation in bending. The basic trends of crack propagation in samples of concrete with OSA and BFs are simulated using a two-dimensional Finite Element (FE) model considering only material degradation on the opening crack surface and experimental data of three- and four-point bending tests. Crack propagation is modeled using the bridging law approach. A surrogate model for predicting the peak loading as a function of tensile strength and fracture work was created. An examination of the results of the FE model shows that the bilinear and nonlinear bridging law functions best describe the crack growth in the analyzed material. A comparison of experimental and modeled results showed that the length of the composite BF strongly affects the accuracy of the numerical model.

Stabilization of Road Embankments on Peat Soils Using Oil Shale Ash and Pozzolanic Additives

Using kukersite oil shale ash for the stabilization of organic-rich soils has been extensively studied but without much success. The main reason for this is the retarding effect of humic acids present in organic-rich soils on the formation of the C–S–H (calcium–silicate–hydrate) phase, which effectively prevents the solidification of cementitious materials in peat soils. Based on the studies performed at the University of Tartu, we have developed a novel method for the in situ mass stabilization of peat soils using waste materials (calcareous fly ash and silica fume). In this manner, the perfect hardening of peat–ash mixtures (to each 1 m3 of soil, 150–400 kg ash, 25–50 L pozzolanic additives, and 2.5–5 kaNaOH were added) can be achieved. A test road embankment was constructed under extremely hard conditions in a peat quarry that is currently in use.

Технология извлечения полезных компонентов из горючих сланцев месторождения Актау

This paper describes technologies for processing of oil shales and determines parameters of thermal decomposition without oxygen access (pyrolysis) and hydrometallurgical methods for extracting useful components. The following methods are presented: leaching to extract valuable components into a sulfuric acid solution, and selective extraction to ion-exchange resins by sorption of valuable components of vanadium and molybdenum. The presented methods are not implemented on an industrial scale, since there is no oil shale processing in the Republic. Perspective technological schemes of oil shale ash processing are analyzed. The process involves the addition of sodium chloride to the process of thermal decomposition without access to oxygen (pyrolysis). The resulting ash is leached in vats with sulfuric acid 160 g/l, at room temperature, T : W = 1 : 5, duration 60 minutes. The resulting metal-bearing sulfuric acid solution is filtered and sent to sorption and precipitation. Extraction of vanadium and molybdenum into solution is more than 60–70 %. It should be noted that with an increase in the consumption of sulfuric acid over 160 g/l, the concentration of metals in the productive solution does not increase. The ion-exchange resins of the English company PUROLITE were used to extract metals from the productive solutions of leaching of oil shale ash from the Aktau deposit: for the extraction of molybdenum — A-100 Mo grade, and vanadium — A-109 grade.

Neutralization of Acidic Industrial Wastes and Fixation of Trace Element by Oil Shale Ash: Formation of a Green Product.

Oil shale is a rock that contains organic matter in a concentration that allows it to be used as an energy source. As a result of the shale combustion process, large amounts of two types of ash are formed: fly ash (∼10%) and bottom ash (∼90%). At present, in Israel, only fly oil shale ash is used, which constitutes a minority of the oil shale burn products, whereas bottom oil shale ash is accumulated as waste. Bottom ash contains a high percentage of calcium in the form of anhydrite (CaSO4) and calcite (CaCO3). Thus, it can be used to neutralize acidic waste and to fix trace elements. This study examined the process of scrubbing the acid waste by the ash, its characterization pre- and post-upgrade treatment, to test its suitability as a partial substitute for aggregates, natural sand, and cement in concrete mixtures. In the current study, we compared the chemical and physical characterization of oil shale bottom ash before and after upgrading the ash via chemical treatment. In addition, its utilization as a scrubbing reagent for acidic wastes from the phosphate industry was studied.