Ash Composition Research Articles

Synthesis, Characterization, and Thermal Properties of Mg-3Ca/Fly Ash Composites

Synthesis, Characterization, and Thermal Properties of Mg-3Ca/Fly Ash Composites

Зольность тарного картона. Проблемы и пути их решения

This article covers the study of the nature of ash content of containerboard from waste paper, as well as fractional composition of ash. With increasing use of waste paper with white top layer and deterioration of conditions of collecting and storing waste paper at the storing fields, there is an increase in mineral impurities in the incoming waste paper. This fact leads to increased load on cleaning equipment and accelerated wear of working parts of sorters and mills. Ash content includes all mineral impurities without any division into fractions or sources of occurrence. Reducing the total ash content of products becomes quite difficult, because suppliers of cleaning equipment guarantee the efficiency of removing only those mineral contaminants, the size of which is greater than the a certain value (70…100 microns). Standard methods for determining ash content of paper and cardboard do not imply the possibility of determining the fractional composition. To solve this problem, the authors applied a method for determining the fractional composition of granular materials in a certified laboratory. The method of sample preparation for analysis was developed by the authors independently. Based on the results of the research, it was possible to identify the volume of the ash fraction that can be separated by means of cleaning equipment. This volume is mainly quartz sand of various degrees of grinding, and the other part of ash content is the filler, calcium carbonate, which cannot be effectively removed from the technical process due to the small particle size. To determine the content of calcium carbonate, qualitative and quantitative research methods were used - treatment with hydrochloric acid followed by washing and weighing of the resulting sludge. This test methodology and the results of the research work can serve as a basis for the need to install additional or upgrade the existing cleaning equipment. Unfortunately, at present there are no studies concerning abrasive ability of the main filler – calcium carbonate, and its influence on service life of the corrugator. Also, at the moment there are no data concerning critical size of ash particles, which lead to accelerated wear of the rolls. At the same time, determination of critical particle size is important from the point of view of setting up and upgrading of cleaning equipment of the stock preparation department of a typical paper mill processing waste paper raw materials. For citation: Zhirnov D.N., Dernova E.V., Gorazdova V.V., Dulkin D.A. Ash Content of Containerboard. Problems and Solutions. Lesnoy Zhurnal = Russian Forestry Journal, 2023, no. 5, pp. 184–194. (In Russ.). https://doi.org/10.37482/0536-1036-2023-5-184-194

Hydrothermal dewatering of low-grade coal: Product evaluation and primary component analysis of ash deposition

The hydrothermal dewatering (HTD) process was carried out using 16 coal samples obtained from several regions in Indonesia. This research aims to identify the dominant parameters that influence ash deposition during coal combustion in a boiler or gasifier due to the HTD process. This research was conducted due to the lack of clear and comprehensive information regarding this issue. Therefore, to understand the effect of HTD on ash deposition, an analysis of the chemical composition of ash and the ash melting temperature (AFT) was carried out. To verify the data obtained from the experimental analysis, statistical methods such as paired sample t-test and primary component analysis were applied to obtain the dominant parameters influencing ash deposition due to HTD. Eight parameters, namely SiO2, Fe2O3, slagging viscosity index (SR), Babcock index (Rs), initial deformation temperature, softening temperature, hemispherical temperature, and fluid temperature under oxidative conditions, have the greatest influence on ash deposition due to the HTD process. Based on the average values of SR and Rs, raw coal and processed coal samples have the same ash deposition trend. On the other hand, based on AFT under oxidation conditions, processed coal has a higher AFT, indicating that the tendency for ash deposition is lower than raw coal. Therefore, the HTD process can be used to improve the quality of low-grade coal. As an implication, low-grade coal, which has not been widely utilized in Indonesia, due to several constraints regarding its characteristics, through the HTD process can be optimized where coal utilization is a bridge towards the use of green energy which is being intensively pursued.

Simulation of Furfural and Levulinic Acid Production from Lignocellulosic Biomass

Furfural and levulinic acid are chemicals that can be produced from lignocellulosic biomass. In this research, mass balance simulation of furfural and levulinic acid production at scale of 100 tons of biomass/year was examined. This research using various models of kinetic reaction and biomass to solvent ratio from lignocellulosic biomass raw materials consisting of cellulose, hemicellulose, lignin, ash, and water composition of 35%, 30%, 25%, 3%, and 7%. The kinetic models used in this research were separate kinetic models and simultaneous model (model-3). The separate kinetic models were divided into two models which separate kinetic model 1 (model-1) and separate kinetic model 2 (model-2). SuperPro Designer 9.0 software was used to calculate mass balance simulation. From the research, it was found that variations in kinetic reaction model affected furfural and levulinic acid production. Higher biomass to solvent ratio produced higher furfural and levulinic acid production. The highest furfural produced from simulation process was kinetic reaction model-2 with a biomass to solvent ratio of 1:30 and 0.67 liter furfural/hour. While the highest levulinic acid produced from the simulation process was kinetic reaction model-1 with a biomass to solvent ratio of 1:30 and 2.37 liter levulinic acid/hour.

Prediction of ash fusion temperatures of municipal solid waste incinerator ash based on support vector regression

The ash fusion temperatures (AFTs) of the municipal solid waste incinerator (MSWI) ash and slags is the main indicator to judge its slagging characteristics. Support vector regression (SVR) algorithm is more appropriate for creating an AFT prediction model than the classic regression method because it can adjust to a wider range of ash sample types in a wider range of areas by avoiding underfitting and overfitting. In this paper, SVR prediction models for the deformation temperature (IDT), softening temperature (ST), hemisphere temperature (HT), and flow temperature (FT) of ash are constructed using the ash chemical composition and AFTs dataset of coal ash and biomass ash and other ash. The AFTs of fly ash, bottom slag, and other ash in the municipal solid waste incinerator are predicted. With average relative errors of 1.98 % and 3.56 % and maximum relative errors of 5.21 % and 5.2 %, respectively, the results demonstrate that ST and FT have greater prediction accuracy. IDT and HT both provide poor predictions, with maximum relative errors of 14.08 % and 9.36 %, respectively, and average relative errors of 10.06 % and 5.95 %, respectively. Additionally, the impact of removing various numbers of outlier samples from training data on prediction accuracy, and the impact of test sample measures, such as ash composition analysis and AFTs determination, on prediction accuracy are analyzed and examined.

Nutritional quality of eastern school whiting (Sillago flindersi) under contemporary and future environmental conditions

AbstractClimate‐driven environmental change is increasingly impacting global fisheries and marine resource use. Fisheries provide a broad range of economic, social and cultural benefits while delivering essential contributions to nutrient security and human health. Despite this, little is known about how climate change will impact the availability and quality of seafood‐derived nutrients. Here, we quantified spatial and temporal changes in the nutritional quality of the commercially harvested eastern school whiting, Sillago flindersi, sampled throughout the south‐east Australian ocean warming hotspot. Several nutrients measured in S. flindersi, including protein, ash, polyunsaturated fatty acids (PUFA) and the omega‐3 PUFA–docosahexaenoic acid (DHA, 22:6ɷ3), were related to one or more environmental factors (sea bottom temperature, depth and chlorophyll). We also detected seasonal variability in DHA and ash composition throughout the species' commercially harvested distribution. Historical and future spatial modelling predicted a decrease in DHA of up to 6% with increasing ocean temperature under future Representative Concentration Pathway (RCP) 4.5 and 8.5 emission scenarios. Overall, our results identified S. flindersi as a rich source of protein and essential PUFAs for human consumers and supported emerging evidence that reductions in seafood‐derived essential nutrients may occur under future ocean warming, specifically reductions in omega‐3 fatty acids. The development of nutritional quality forecasting tools for seafood holds the potential to inform fishers and managers of locations and times of the year to target species with optimal nutritional quality.

Medical Waste Incineration Ash Waste: Impact On Environmental Health And Its Potential To Be Used For Paving Blocks

ABSTRACT : It is known that medical waste has increased in recent years due to the Covid-19 pandemic, which was followed by an increase in ash from burning medical waste processing using incinerators. The objective of this study is to determine the impact of using medical waste incineration ashes on health and the environment, as well as the potential for using solidification techniques to make the ash into paving blocks. The ash used was obtained from a medical waste processing facility in Surakarta, Indonesia's Central Java. The test object was created using seven different combinations of ash, sand, and cement with a water-cement ration of 0.5 and cured for 28 days. The optimum compressive strength condition was determined as the basis for the composition of medical waste incineration ash as a mixture of paving block raw materials, which was then tested for the content of heavy metal compounds using the SNI 8808: 2019 method. According to research, the ash from medical waste incineration contains heavy metal compounds such as Pb, Ni, Cu, and Cd and has the potential to be used as a mortar mixture. Six of the seven mortar compositions with the addition of incineration medical waste ash met the compressive strength requirements of SNI 03-0691-1996 for category D paving blocks to be used in parks and other places.

Monitoring of carbon dioxide and equilibrium moisture content for early detection of physicochemical and morphological changes in soybeans stored in vertical silos

In the context of grain storage, impurities and soybeans defects in soybeans can significantly impact the equilibrium moisture content. This, cause moisture migration and heating of the stored product, leading to increased respiratory activity. Furthermore, temperature measurements within stored grain mass do not provide sufficient information for effective grain quality monitoring, primarily due to the grains excellent thermal insulating properties. To address this issue, we propose a different approach: monitoring the equilibrium moisture content and CO2 concentration as indicators of soybean respiration within the intergranular spaces of the stored grain mass. This study propose monitoring the CO2 concentration in the intergranular air along with environmental variables for early detection of physicochemical and morphological changes in soybeans stored in vertical silos using near infrared spectroscopy, X-ray diffraction and scanning electron microscopy. Thermogravimetry and spectrometry analyses revealed that the interrelationships among variables had a direct impact on soybean quality attributes. Specifically, the presence of soybeans with 5.2 % impurities led to an increased in respiration rates, resulting in a CO2 concentration of up to 5000 ppm and the consumption of up to 3.6 % of dry matter. Consequently, there were changes in the percentage of ash, proteins, fibers, and oils compositions. These findings highlight the potential for indirect assessments, enabling the prediction of physicochemical quality and contamination of soybeans stored in vertical silos through continuous monitoring of CO2 concentration and equilibrium moisture content.

Does the Mineral Composition of Volcanic Ashes Have a Beneficial or Detrimental Impact on the Soils and Cultivated Crops of Ecuador?

Agriculture is an important economic sector for Ecuador, sustained by food crops like maize, potatoes, and vegetables cultivated in the highlands while cash crops such as coffee, bananas, cacao, and palm oil are grown on the coastal plains. But, Ecuador is also a country under the influence of several natural hazards due to its geographical location, atmospheric dynamics, and geological characteristics. One of the main risks to food security is the presence of a large number of active volcanoes scattered all over the country with the most representative enemy, the falling volcanic ash. The bibliography in general highlights the potential toxicity of volcanic ash from a human health perspective, but it also negatively influences plant development at the seed's germination, as well as low crop pollination, damaged fruits, reduced leaf respiration depending on the type of crop, the developmental stage, the ash layer, and the climate. The mineral composition of the volcanic ash can also be beneficial for the soil by increasing fertility but at the same time with contrasting effects on plants due to the influence on soil characteristics such as pH, soil aeration, and biodiversity, which can detrimentally affect some crops.

Engineering and microstructural properties of carbon-fiber-reinforced fly-ash-based geopolymer composites

Alkali-activated fly ash and slag-based geopolymer composites offer sustainable cement alternatives to conventional cement materials. Incorporating fibers mitigates issues such as brittleness, insufficient toughness, and cracking in geopolymers. However, limited systematic research exists on the influence of carbon fiber characteristics on geopolymer performance. In this study, the effects of carbon fibers having varying lengths (6 mm and 12 mm) and volume fractions (0%, 0.2%, 0.4%, 0.6%, 0.8%, and 1.0%) on multiple properties of geopolymers, including workability, water absorption, porosity, mechanical strength, drying shrinkage, uniaxial tensile properties, fracture toughness, and microstructure, are investigated. Results indicate that the incorporation of carbon fibers diminishes the flowability of the geopolymer mix and accelerates its setting time. Parameters such as water absorption, porosity, and compressive and flexural strengths initially decrease and then increase with increasing fiber content. Carbon fibers positively affect drying shrinkage, particularly during the early stages. The fiber bridging effect enhances uniaxial tensile properties, reducing brittleness. Carbon fiber addition improves the fracture toughness of the composite, achieving an optimal volume fraction at 0.6%. At this volume fraction, carbon fibers of 6 mm length exhibit better crack initiation toughness and resistance to instability cracking than fibers of 12 mm length. Moreover, the presence of carbon fibers promotes the formation of hydration products, minimises the occurrence of microcracks, and interacts synergistically with the slurry matrix to enhance overall crack resistance and material toughness. This study provides a valuable reference for the development and application of fiber-reinforced geopolymer materials.

Thermo-kinetic Study of Genetically Different Carbon-Source Materials.

A nonisothermal thermogravimetric analysis (TGA) technique was applied to determine the devolatilization kinetic parameters of completely different genesis samples of four groups: coal, biomass, lignite, and petcoke. The physical and chemical characteristics were determined using the proximate and ultimate analysis and the ash composition profile using the X-ray fluorescence method. Heating rates of 10, 15, and 20 °C/min were used in the temperature range of 25-1000 °C during the slow pyrolysis under an inert gas atmosphere. A widely used and proposed first-order Coats-Redfern kinetic model was applied, which showed the highest values of activation energies (Ea) for the petcoke sample from 57.17 to 67.58 kJ/mol at three different heating rates, while the lignite sample represented the lowest Ea values between 12.84 and 16.03 kJ/mol. The thermo-kinetic behavior was explained based on the catalytic effect of the ash composition profile, morphology, and structure of the substances determined using different analytical techniques. For the TGA process, the application of scanning electron microscopy, Fourier-transform infrared spectroscopy, etc., for the physiochemical analysis of the four genetically different carbon-source materials represented the novelty of the present work.

Study on preparation of ultra-clean coal from bituminous coal using the ionic liquid extraction

ABSTRACT In order to realize clean and efficient utilization of low rank coal, ultra-clean coal preparation is an important method. A clean and efficient method of producing ultra-clean coal is urgently needed, given the high environmental impact and corrosiveness of the chemicals used in the traditional chemical preparation of ultra-clean coal. In this study, ultra-clean coal was prepared by leaching using acidic imidazole ionic liquids, and the effects of temperature, time and concentration on the reaction process were investigated. The ash composition of the sample and the ash removal mechanism under the ionic liquid were revealed, and the evolution law of the microstructure and functional group characteristics was clarified. The research showed that the concentration and temperature had a large influence on the ash content of the product during the leaching process, and the reaction time had a small influence. The minimum ash content of the ultra-clean coal could reach 0.89% (dry basis). In the ionic liquid system, iron, calcium and magnesium in the coal were effectively removed, the iron oxide content was significantly reduced and calcium salts except calcium sulfate were effectively removed, while periclase was almost completely removed. However, the removal of silicon and aluminum was poor. Most of the alumina and silica remained in the ultra-clean coal. Extracted coal had more cracks and rougher surface than raw coal, the BET surface area decreased from 2.8579 to 2.4032. Under the influence of ionic liquid, the Aar/Aal ratio, which evaluates the aromaticity of coal, increased from 0.3702 to 0.8569, indicating that the aromaticity of coal was significantly improved. The CH2/CH3 ratio describing the length and branching degree of aliphatic chains in coal decreased from 4.0849 to 3.1516 which showed that ionic liquids can effectively reduce the length of aliphatic side chains, weakening the coal’s oxidizing activity. The pyrolysis curve of coal shifted to the high temperature zone and the peak temperature increased, indicating the effect of ionic liquids on the chemical stability of coal.

Optimizing abrasive wear loss of Aluminum/Fly Ash and Aluminum/Rice Husk Ash metal matrix composites using AHP-EDAS and AHP-COPRAS techniques for enhanced performance

Lightweight aluminum metal matrix composites (MMCs), Aluminum/Fly Ash and Aluminum/Rice Husk Ash were developed using the stir casting route for automotive applications. As a result of the above consideration, automotive parts such as brake rotor and connecting rod, etc. have been the subject of research in a variety of areas. Finding the right material for the design under consideration requires an effective approach to material selection. Multi-criteria decision-making (MCDM) processes are helpful when dealing with ambiguity in material selection. To rank aluminum-Fly Ash (FA) and Aluminum-Rice Husk Ash (RHA) composites, integrated MCDM methodologies such as Analytical Hierarchy Process (AHP)–Evaluation Based on Distance from Average Solution (EDAS) and AHP–Complex Proportional Assessment (COPRAS) are utilized. The weights for each criterion are determined using the AHP approach, and the EDAS and COPRAS techniques are then used to rank the items. Three different particle sizes (0–53, 54–74, and 75–105 µm) of the reinforcement have been chosen for the selection criteria. Density, hardness, ultimate tensile strength, and compressive strength, and specific wear rate, and coefficient of friction of the manufactured composites evaluated. A thorough examination of the MCDM methods found that Al-FA composites with particle sizes of 54–74 µm were the most effective.

Studying the properties of ash and slag waste for use in the manufacture of construction products

Purpose. The research purpose is to study the physical-chemical properties of ash and slag waste generated during the coal combustion at the Ekibastuz field in Kazakhstan, to determine the possibility of using waste as a secondary resource to reduce the negative human impact on the environment. Methods. The research uses the methods of X-ray phase and differential thermal analysis, as well as chemical analysis. The X-ray phase analysis makes it possible to determine the phase composition and structure of ash and slag wastes, while differential thermal analysis is used to study their behavior with temperature changes. A chemical analysis is performed to determine the composition of ash and slag. Findings. The chemical and granulometric composition of ash and slag waste from the Ekibastuz field coal combustion has been determined. Analysis of the ash chemical composition showed that its main components are silicon and aluminum oxides, as well as a significant amount of iron oxide. The results obtained confirm the possibility of using ash and slag waste as a secondary raw material to reduce the negative impact on the environment. Originality. It has been revealed that the thermal conductivity, ultimate strength and water-absorption of ceramic brick samples depend on the amount of ash added and the firing temperature. The possibility of obtaining building materials with minimum cement content has also been substantiated, which is a new and promising approach, given the high cost of cement as the main building material. Practical implications. The practical value of the research is in solving environmental problems associated with the use of ash and slag waste. Using these wastes as a secondary raw material, it is possible to reduce the anthropogenic burden on the environment, as well as the volume of ash dumps. In addition, vacant land previously occupied by ash and slag mixtures can be used for economic purposes.

Технология утилизации и использования золошлаковых отходов для обеспечения экологической безопасности региона

Introduction. By burning coal, thermal power plants receive thermal energy and generate electrical energy. The negative side of this process is the formation of ash and slag waste. The relevance and significance of this problem is due to the fact that technogenic waste from the CHP is not processed, and current ash waste accumulates and occupies huge areas, which removes them from land use. This problem is especially relevant for Almaty, where ash and slag waste from the burning of coal from the Ekibastuz deposit in Kazakhstan is concentrated. Currently, in Kazakhstan, ash and slag waste from thermal power plants is accumulated in the amount of more than 500 million rubles, the reserves of which continue every year. The storage of ash and slag waste leads not only to the seizure of significant land areas, but also causes very significant pollution of almost all environmental components in the area of their location. Therefore, at mining enterprises that have their own thermal power plants, it is very urgent to solve the issues of reducing the burden on the environment by developing technologies for the disposal of ash and slag using them in the production of road surfaces. The purpose of the research. The study of the physico-chemical properties of ash and slag waste to reduce the anthropogenic load on the environment. Research materials. For the research, samples of Ekibastuz coal ash taken from the ash dumps of the CHPP-3 in Almaty were used. Research methods. The work was carried out using a DRON-3M diffractometer to determine the phase composition of ash and slag waste. The chemical composition of fly ash was determined by the X-ray fluorescence spectrometer EDX-8000. The granulometric composition was analyzed using an Analizette 22 MicroTec Fritsch GmbH (Germany). Microphotography of fly ash was taken using a Superprobe-733 scanning electron microscope with software. To determine the physical and mechanical properties of the bases using bitumen-ash-slag binder, the crushed stonegravel-sand mixture is initially mixed with ash-slag. From the finished bitumen – mineral mixture, samples are prepared by pressing – cylinders with a size of 5x5 cm. The ultimate strength was determined for two types of samples. The first are dry, tested immediately after receiving samples by pressing, the second are samples that are tested after water saturation. Research results and discussion. Based on the study of the physic-mechanical properties of the binder with the use of ash and slag, a technology for obtaining BZSHV has been developed. Various compositions are proposed – types of bitumen, depending on the type of base of asphalt concrete mixtures. Studies have shown that the introduction of ash and ash-slag mixtures from the burning of stone and brown coals as a mineral powder for the preparation of asphalt concrete mixtures makes it possible to obtain a material with regulatory physic-chemical characteristics. Conclusion. The results of the study of the main physic-chemical characteristics of the ash of Ekibastuz coal, selected from the ash dumps of the CHP-3 of Almaty city, are presented. It is shown that the use of ash in the manufacture of asphalt pavement will reduce the area of occupied land and the load on the environment, as well as improve the operational characteristics of the pavement. Suggestions for practical application. The results of the research can be useful in solving the environmental problem of utilization of ash and slag waste of the CHP.

Качество рыбных котлет «пемпек» из змееголова красного (Channa micropeltes) с тыквенным пюре

Pempek is an authentic traditional dish of Indonesian cuisine. As a popular food, it needs to be both tasty and nutritious. Mashed pumpkin can add some health-beneficial properties to the traditional pempek and reduce its carbohydrate content. This research featured pempek made of farmed toman fish (Channa micropeltes), which is an affordable raw material. The research objective was to evaluate the consumer acceptance of the experimental pempek based on its sensory assessment and a folding test. This research also revealed the proximate composition, β-carotene, and amino acids in the pempek samples. 
 The research procedure included the following stages: making pumpkin puree; making pempek by substituting tapioca flour with pumpkin puree (control: 0%, Formulation 1: 10%, Formulation 2: 20%); sensory assessment and folding test; proximate analysis; β-carotene analysis; and amino acid analysis. 
 A greater proportion of pumpkin puree improved the appearance, color, aroma, flavor, and texture values of the experimental sample. Based on the folding test, the elasticity of pempek decreased as the pumpkin share increased. Pumpkin puree improved the quality of pempek in terms of its protein, moisture, ash, carbohydrate, β-carotene, and amino acid composition. Formulation 2 with 20% of tapioca flour substituted with pumpkin puree showed the best results for protein (7.91%) and amino acids (10.27%), as well as the lowest carbohydrate content (26.76%). 
 Mashed pumpkin proved to be an excellent substitute of tapioca flour in the traditional Indonesian pempek fishcake as it improved both its sensory profile and nutritional value.

Effects of Fly Ash Composition to Mitigate Conversion of Calcium Aluminate Cement Composites

Calcium aluminate cement (CAC) is one of the alternative cements that is widely used for special applications. However, during the hydration process degradation of CAC microstructure, the so-called hydrate conversion process, hexagonal calcium aluminate hydrate (CAH10) transforms into a cubic (C3AH6) phase, resulting in increased porosity and reduced strengths. It is known that alternative means for stabilizing the CAC conversion are conducted by introducing fly ash (FA) in CAC, where its microstructure is attributed to aluminosilicates. However, no study has yet been conducted on different FA compositions influencing CAC performance. This study aims to evaluate the effects of different compositions of FA on CACs’ fresh and hardened characteristics. Results revealed that the microstructure was denser when CAC was mixed with FA. Regarding reactivity, CAC with calcium-rich FA systems is 13% faster than the silica-rich one. The higher the density and the lower the porosity of calcium-rich FA mixtures were found compared with silica-rich FA in both micro- and macro-structures. As seen in the microscopic structure, this is due to the calcium-rich phase formation.

Phase recognition in SEM-EDX chemical maps using positive matrix factorization

Images from scanning electron microscopy (SEM) coupled with energy-dispersive X-ray spectroscopy (EDX) are informative and useful to understand the chemical composition and mixing state of solid materials. Positive matrix factorization (PMF) is a multivariate factor analysis technique that has been used in many applications, and the method is here applied to identify factors that can describe common features between elemental SEM-EDX maps. The procedures of converting both graphics and digital images to PMF input files are introduced, and the PMF analysis is exemplified with an open-access PMF program. A case study of oxygen carrier materials from oxygen carrier aided combustion is presented, and the results show that PMF successfully groups elements into factors, and the maps of these factors are visualized. The produced images provide further information on ash interactions and composition of distinct chemical layers. The method can handle all types of chemical maps and the method is not limited solely to SEM-EDX although these images have been used as an example. The main characteristics of the method are:•Adapting graphics and digital images ready for PMF analysis.•Conversion between 1-D and 2-D datasets allows visualization of common chemical maps of elements grouped in factors.•Handles all types of chemical mappings and large data sets.

Influence of fly ash on thermo-mechanical and mechanical behavior of injection molded polypropylene matrix composites

Polypropylene composites find widespread application in industries, including packaging, plastic parts, automotive, textiles, and specialized devices like living hinges known for their remarkable flexibility. This study focuses on the manufacturing of polypropylene composite specimens by incorporating varying weight percentages of fly ash particles with polypropylene using a twin-screw extruder and injection molding machine. The composites were comprehensively tested, evaluating tensile, compressive, and flexural strength, solid-state and polymer melt properties, modulus, damping, and thermal response. The findings reveal that the compressive strength of polypropylene increases up to 2 wt% of added fly ash particles and subsequently exhibits a slight decline. Tensile strength demonstrates an increase up to 1 wt% of fly ash, followed by a decrease with a 2 wt% addition, and then a subsequent increase. Flexural strength shows improvement up to 3 wt% fly ash addition before declining. The storage modulus curve is categorized into three regions: the glassy region (up to 0 °C), the glass transition region (0–50 °C), and the glass transition region of polypropylene (>50 °C), each corresponding to different molecular motions. Weight loss curves exhibit similar trends, indicating uniform pyrolysis behavior attributed to consistent chemical bonds. Plastic degradation commences around 440 °C and concludes near 550 °C. Additionally, elemental mapping of fly ash composition identified various elements such as O, Si, K, Mg, Ca, Cl, Na, P, Al, Fe, S, Cu, Ti, and Ni. These findings offer valuable insights into the mechanical and thermal properties of polypropylene composites reinforced with fly ash, rendering them suitable for a wide range of industrial applications necessitating strength and durability across temperature variations.

Characterisation of Ground Coal Bottom Ash With Different Grinding Times

The physical and chemical composition of Ground Coal Bottom Ash (GCBA) exposed to varying grinding periods is discussed in this article. CBA was pulverised for 20 hours, 30 hours, and 40 hours in a ball mill machine. Particle Size Analyzer (PSA) and X-ray Fluorescence (XRF) instrument were used to characterise GCBA. According to the results of the tests, GCBA with a grinding duration of 40 hours generates the largest percentage of the finest particle (50-1000 nm) at 4%, the specific surface area is 13528.18 cm2/cm3, and the specific gravity (SG) is 2.54. According to the XRF results, there are no significant variations in the chemical compositions of the CBA with varying grinding periods. At 20, 30, and 40 hours grinding time, the primary oxide element for SiO2 is 51.5%, 53.8%, and 52.3%, while Al2O3 is 14.3%, 15.1%, and 14.6%, and Fe2O3 is 5.08%, 5.27%, and 5.07% respectively. The sum of three primary oxide constituents surpasses the 70% ASTM C618 limit for pozzolanic material Class F fly ash.