Particle Size Of Raw Materials Research Articles

Characterization, performance evaluation and optimization of wheat straw – bagasse blended fuel pellets

This study was carried out to assess the fuel pellets produced from wheat straw and sugarcane bagasse. The wheat straw and bagasse were blended into four ratios including; 10:90, 30:70, 70:30 and 90:10 (wheat straw: bagasse) and developed into fuel pellets. The fuel pellets were characterized to determine the moisture content, volatile matter, fixed carbon, ash content, calorific value, bulk density and mechanical durability. The ignition time, burning rate and specific fuel consumption of the wheat straw – bagasse blended fuel pellets were studied at varying blend ratios (10:90, 30:70, 70:30 and 90:10), moisture contents (9.1%, 10.6%, 12.6% and 14.7%) and raw material particle sizes (2 mm, 4 mm, 6 mm and 10 mm). Results indicated that the wheat straw: bagasse blend ratios containing more proportion of bagasse (30:70 and 10:90) recorded a shorter ignition time, higher burning rate and lower specific fuel consumption. Larger raw material particle sizes exhibited shorter ignition time, higher burning rate and specific fuel consumption. Moreso, the fuel pellets with low moisture contents also recorded shorter ignition time, higher burning rate and lower specific fuel consumption. It was concluded that fuel pellets with high quantity of bagasse, large particle sizes and low moisture content demonstrated favorable combustion characteristics. Response surface methodology was used in the optimization so as to determine the optimum combination of blending ratio, moisture content and raw material particle size that would result in the lowest ignition time, highest burning rate and lowest specific fuel consumption. Results indicated that an optimum combination of a wheat straw: bagasse blend ratio of 10:90, moisture content of 14.70% and a particle size of 10.00 mm resulted in the lowest ignition time, highest burning rate and lowest specific fuel consumption.

A comprehensive study of melt foaming in E‐glass batch‐to‐melt conversion process: Effects of sulfate content and chemistry of raw materials

AbstractControl of sulfate‐induced melt fining without excessive foaming is one of the critical steps in maintaining the stability of E‐glass fiber manufacturing processes. Besides, the efficiency of combustion or energy utilization is directly affected by the extent of the melt‐foaming. A fundamental understanding of key factors affecting melt foaming under the simulated oxy‐fuel combustion environment will enable commercial E‐glass fiber production to optimize both batch chemistry and operation conditions to achieve adequate furnace control. In this study, six types of E‐glass batches with the same target glass composition were prepared by using four different CaO sources; calcined limes with different SO3 contents, limestone, limestone with sodium sulfate, and a mixture of limestone and calcined lime. All batch samples were examined by HTMOS‐EGA system (high temperature melting observation system with evolved gas analysis). HTMOS enables monitoring batch‐to‐melt conversation steps by using a high‐resolution camera and EGA detects the evolved reaction gaseous, such as CO, CO2, and SO2 via an Fourier transform infrared (FTIR) gas analyzer. Gases of water vapor, N2, and O2 were introduced accordingly into the fused quartz crucible to simulate similar oxy‐fuel atmosphere of the furnace operation. This study aimed to investigate the effects of different SO3 contents in batches and different raw material chemistries on the foam formation in E‐glass melts under the oxy‐fuel atmosphere. Different raw materials were characterized by mineralogical analysis, chemical analysis, particle size distribution, chemical oxygen demanding (COD) level, and Brunauer–Emmett–Teller (BET) analysis. Although some of the batches contained the same SO3 content, different foam formations resulted from the effect of the batch chemistry. Our detailed HTMOS‐EGA investigations show that not only SO3 content in the batch affects foam formation in E‐glass melts, but also raw material chemistry and particle size have strong effects on the melt foaming in E‐glass batch melting, especially for those of ingredients having hydroxide phases and/or finer particles with higher specific areas.

Study on Recovery of Lithium from Lithium-Containing Aluminum Electrolyte

The current process of recovering lithium from wasted aluminum electrolyte mostly entails extracting lithium from lithium-containing aluminum electrolyte by acid leaching and dissipation. Aiming at the disadvantages of the existing treatment method, such as the long process flow, environmental pollution, poor working environment, etc., we propose a new technology to extract lithium from the wasted aluminum electrolyte and systematically investigate the effects of raw material particle size, holding time, temperature and other factors on the recovery of lithium. The results show that the better process conditions for the recovery of lithium are as follows: the raw material particle size is 75~150 μm, the additive is CaCl2, the mass ratio of calcium chloride to lithium-containing aluminum electrolyte is 3:5, the reaction temperature is 1473 K, and the holding time is 3 h. After the product of the reaction is crushed and leaching is carried out by using deionized water (pH = 6.8), the temperature of the leaching is 368 K, the leaching time is 3 h, and the solid–liquid ratio is 1/3, and the leaching rate of Li can be up to 75.1%. In addition, the purity of the recovered AlF3 is more than 92.7%. This process realizes the comprehensive and efficient use of lithium-containing aluminum electrolyte and provides a new idea for the development of lithium extraction technology from lithium-containing aluminum electrolyte.

In Situ Ca‐ and Mg‐ Codoped Biochar Derived from Tobacco Stem for Phosphate Adsorption and Desorption

AbstractPhosphorus is an important element for plant growth. The efficient use and recovery of phosphorus is crucial due to limited phosphate resource reserves. This study explored the potential application of an in situ Ca and Mg co‐doped biochar derived from tobacco stem to reclaim and reuse phosphate from aqueous solutions. We performed various batch adsorption experiments and industrial analysis based on different parameters. The findings indicate that biochar prepared using the raw material particle size range of 0.85–2 mm and pyrolyzed at 800 °C presented good pore structure and specific surface area. Ca and Mg elements in biochar exhibited great influence on its phosphate adsorption property. The maximum phosphate adsorption capacity of the tobacco stem‐based biochar was 54.66 mg/g, and the experimental data agreed with the Langmuir equation, suggesting monolayer adsorption. The adsorption process conformed to the pseudo‐second‐order kinetic equation, indicating that chemisorption was the dominant adsorption process and that the adsorption was controlled by intra‐particle diffusion. Furthermore, phosphate adsorbed on tobacco stem‐based in situ Ca and Mg co‐doped biochar was released under acidic, alkaline, and neutral conditions. Therefore, in situ Ca and Mg co‐doped biochar prepared from tobacco stems is a potential environmentally friendly and low‐cost adsorbent for phosphorus recovery.

The Effect of Leaching Duration and Solid/Liquid Ratio on Lithium Extraction from Mica Schist Used Hydrochloric Acid Process

Lithium demand has increased rapidly in the last few years because lithium is a metal that is important in technology, like electronic equipment and electric vehicles. One of the primary lithium resources is lithium ore, which contains minerals such as spodumene and lepidolite. Mica schist is one of the lithium ore sources that is indicated to contain lithium. The mica schist used in this research was from Kebumen, Central Java, Indonesia. This raw material indicates a lithium mineral called lepidolite. The aims of this research were to find out the potential of local Indonesian minerals as raw materials for lithium extraction processes in lithium-ion battery (LiB) applications, with the effect of leaching time and solid/liquid ratio. The leaching agent used in this research was 2 M chloride acid (HCl). Variables of this research were-100 mesh for particle size of raw material, 1:5, 1:10, 1:15, and 1:20 (g/ml) for solid/liquid ratio, 30, 60, 90, and 120 minutes for leaching time, and 70 °C for leaching temperature. Inductively Coupled Plasma (ICP-OES) analysis was done on this research to determine the mica-schist composition. The optimum lithium percentage that was obtained in this research was 40.65% on a solid/liquid ratio of 1:5 (g/ml) and a leaching time of 120 minutes.

Kinetics of extracting valuable components from Ti-bearing blast furnace slag by acidolysis with sulphuric acid.

Ti-bearing blast furnace slag is a kind of solid waste produced by Pangang Group Company through the blast furnace smelting method. A variety of valuable components can be extracted from the Ti-bearing blast furnace slag after acidolysis with concentrated sulphuric acid. In order to study the kinetics of acidolysis, this paper investigated the effects of the acidolysis temperature, acid-slag ratio and raw material particle size on the overall extraction rate of Ti4+, Mg2+ and Al3+ components at different reaction times, and simulated the acidolysis process by using the unreacted shrinking core model. The results showed that the acidolysis process was controlled by internal diffusion with an apparent activation energy of 19.05kJmol-1 and the semi-empirical kinetic equation of the acidolysis process was obtained.

Effect of Non-Plastic Raw Materials Particle Size on Technological Properties of the Single-Fired Wall Tile Bodies

This study has investigated the effect of particle size of non-plastic components of quartz and pegmatite on some technological properties of wall tile bodies. For this, quartz-pegmatite mixtures were further milled up to 90 min. before adding into the body composition unlike the standard body composition, where quartz and pegmatite were used as-received. The physical and mechanical properties of the bodies were investigated and compared with the standard values. Thermal expansion coefficient and moisture expansion values were determined by a dilatometer. Phase analyses were carried out by X-ray diffraction and microstructural characteristics were studied using a scanning electron microscope. Changes in various technological properties with reducing particle size of the non-plastic components were reported, particularly the increased green and fired strength. It was discussed that using finer particle size non-plastic raw materials of quartz and pegmatite would enable not only increased industrial productivity but also increased producibility of thinner large format wall tiles.

Influence of Raw Material Size on the Microstructure of Graphene Oxide and Its Early Strengthening Properties of Cemen

With the purpose of exploring the influence of raw material size on the structure-performance of graphene oxide (GO) for cement reinforcement, this paper used natural flaked graphite with different particle sizes as raw material to prepare GO nanosheets by a method of enhanced Hummers, and then used scanning electron microscope (SEM) , X-ray diffraction (XRD) , Raman spectrum, infrared spectrum (IR) and other means to characterise the microstructure of GO products in detail, and then investigated the effects of raw material size and graphene oxide GO dosage on its early strengthening effect in cement. The experimental results showed that with the decrease of raw material particle size, the spacing between the layers of GO products is basically the same, while the oxidization degree is increased, and the oxygen-containing groups on the surface are increased. When the GO matt was used to prepare cement mortar with same GO extent, the mechanical strengths at an age of 3 days were found to initially increase and then decrease with the reduction of raw material particle size, and the GO products had the best effect on the improvement of early mechanical strength of cement when the raw material particle size was 13μm. On the other hand, GO matt being obtained from the raw material particles in a size of 13μm was employed to prepare cement mortar with different GO content, of which the 3d strength was found to increase apparently with the increasing GO content, and thus resulted in the increment of 8. 85% to the 3d compressive strength and 6. 34% to the 3d flexural strength for the mortar specimen obtained with a GO content of about 0. 05%, but the further increasing of the GO content is not proposed, which might gave rise of a relative low mechanical strength.

Moroccan Citrus clementina Peels: Optimization of Pectin Extraction and Determination of Chemical and Functional Properties.

Citrus peels are considered a rich source of valuable biomolecules. Pectin is a polymer of polysaccharide acid and is composed of galacturonic acid monosaccharides. In this study, response surface methodology was used to optimize pectin extraction from Citrus × clementina Hort. ex Tan. (Rutaceae) peels using citric acid as an extraction solvent. The effect of the parameters conditioning the extraction process and pectin yield (pH level, temperature, extraction time, solid/liquid ratio, and raw material particle size) was investigated using a Box-Behnken design. The quality of the extracted pectin was assessed both chemically (moisture, ash, protein, and carbohydrate content) and functionally (gelling power and emulsifying activity). According to the screening experiment, the pH level, temperature, and particle size were the main factors influencing the pectin yield. The adjusted mathematical model enabled us to plot response surfaces in order to determine the optimal extraction conditions. The highest production yield of pectin (26.6%) was obtained at the optimal conditions of pH = 1.5, temperature = 100 °C, and particle size = 0.1 mm for an extraction time of 30 min. Compared to the predicted value of 26.6%, the experimental extraction yield of C. clementina was about 21.4% of pectin. Concerning the functional properties, the extracted pectin had a high gelling power of 164 ° SAG and an emulsifying activity of 38.5%.

Preparation of high-performance M-type strontium hexaferrites by ceramic method by optimizing the particle size of raw materials

High-performance strontium hexaferrites (SrM) was prepared by optimizing the particle size of strontium carbonate (SrCO3) and iron oxide (Fe2O3). The microstructure, morphology, particle size and magnetic properties of as-prepared strontium hexaferrite have been examined. The results showed that fine SrCO3 and Fe2O3 powders enhanced reactivity and lowered the starting temperature of the reaction. Magnetic result showed that as-prepared strontium hexaferrite with large saturation magnetization and high coercive force was fabricated by using fine SrCO3 and Fe2O3 powder. The optimum value of saturation magnetization (MS) and coercive force (HC) are 78.97emu/g and 5019Oe respectively. This study facilitated an energy-saving strategy for large-scale production of high-performance strontium hexaferrites in the future.

Use of Post-Consumer Plastics in the Production of Wood-Plastic Composites for Building Components: A Systematic Review

This systematic review study adopted the PRISMA methodology to investigate recent research on wood-plastic composites (WPC) utilizing post-consumer plastics in the construction industry. Initially, 3111 articles were selected from academic databases using keywords such as “wood and plastic composites”, “WPC”, “polymer”, “recycled”, “waste”, “construction”, and “sustainability.” After stringent exclusion criteria, 15 relevant studies on plastic waste composites were identified. These studies often employ post-consumer plastics like polypropylene and high-density polyethylene, along with plant-based fillers, aiming to enhance mechanical properties and reduce reliance on virgin materials. Analysis of these studies revealed that the optimal plastic composition in the composites ranged from 40% to 45% wood and from 50% to 60% plastic, with the extrusion process being the most employed for shaping. Specific factors, such as the use of compatibilizers and the particle size of raw materials, were identified as significant influencers on composite strength. These materials exhibited high thermal stability, rendering them suitable for construction applications exposed to high temperatures. The diversity of plastic waste explored in the studies underscores the potential to tailor thermal properties to specific application demands. These composites facilitate closed-loop plastic recycling, enabling their reintegration into the production chain and offering opportunities for lightweight, durable, and high-performance products in the construction industry. However, beyond the factors examined in the studies, a meticulous assessment of the fire resistance, weather resistance, ultraviolet resistance, moisture absorption, dimensional stability, degradation, long-term durability, impact strength, recyclability, and cost-effectiveness of the material is crucial. Thoughtful consideration of these factors is essential to achieving a comprehensive understanding of the potential and limitations of recycled plastic composites in promoting energy efficiency and sustainability in the construction industry.

Comparison of conventional crushing and high-voltage pulsed power technology as techniques for disaggregating different types of spent magnesia-carbon refractory bricks during recycling

Three different types of spent magnesia-carbon (MgO–C) bricks were chosen to evaluate the liberation of magnesia particles through high-voltage pulsed power technology (HVPPT) and conventional comminution (jaw and cone crushing). The primary objective was to determine how the different types of MgO–C bricks comminute and whether magnesia particles could be restored to their original raw material particle size distribution (PSD).Analytical results revealed that the bricks contained varying amounts of graphite and resin binder, indicating differences in their compositions and therefore comminution properties. The HVPP technique demonstrated its ability to liberate magnesia particles within the +1700 μm fraction, whereas conventional crushing predominantly formed composite particles (containing MgO and carbon) within this size range, with over 63% particles falling in this category. This finding suggests that MgO particles were not adequately liberated during the conventional crushing process, indicating the need for an additional comminution step to achieve the desired liberation.

Feasibility of high-magnesium nickel slag-fly ash as precursor of magnesium phosphate cement and its hydration mechanism

The aim of this study was to investigate the process conditions, hydration reaction products and mechanism of high-magnesium nickel slag (HMNS)-fly ash (FA) as a precursor of magnesium phosphate cement (MPC). The relationships between properties, hydration products, hydration processes, and micromorphology were investigated by engineering properties, XRD, TG-DSC, FT-IR, Raman, and SEM/EDS. The results showed that the optimal process (HMNS/FA = 1.0/0, NH4H2PO4 dosing of 25 wt%, water-cement ratio of 0.26, the maintenance condition is air maintenance, and 200 mesh particle size of raw materials) prepared the cementitious material with 28 d compressive strength of 58.00 MPa and linear expansion rate of only 2.5 %. The hydration process was a multi-stage process, including the dissolution of NH4H2PO4 and pre-treated HMNS (WHMNS), the precipitation of intermediate hydration products and the formation of struvite, and the formation of gelling phases such as -Si-O-P-, -Al-O-P-, and -Si-O-Al-O-P-. Eventually, a high-strength gel-crystal phase structure consisting of gelling phases such as struvite wrapped around unreacted raw materials and struvite crystals was formed. FA was harmful for cementitious material, and impurities and high levels of Ca in FA reacted with phosphate to form hydration products with a loose porous structure (e.g., brushite). The optimal process sample complies with the 52.5R grade of ordinary Portland cement (GB175-2007); its embodied energy was reduced by more than 73.4 % compared to magnesium phosphate cement (MPC), and the corresponding CO2 emission was reduced by more than 74.2 %. Therefore, it has the potential to partially replace MPC from the environmental and feasibility point of view.

Fine Fireclay (FC) technological properties and mineralogy by tuning body composition and raw materials particle size distribution

The Fire-Clay (FC) technology is being revised to cope with challenges involving difficulties in the supplying chains and need to optimize the reuse of waste from production. In this view, the effects induced onto the fundamental FC-ceramic reactions by the introduction of waste from Fire-Clay and Vitreous-China productions are investigated, as a function of the secondary raw materials’ particle size (s) in partial replacement of traditional chamotte. Complex interwoven reactions take place upon changing s, pointing to a general improvement of greification with a reduction of s and increase of the glass content. The role of small nepheline syenite contents (<5 wt%) is also analyzed, leading to relevant effects on greification and thermal expansion. All this opens a chance of introducing waste up to 20–25 wt%, thus providing a relevant contribution to a sustainable production and mitigation of natural resources exploitation.

Evaluation indexes of poplar sawdust and alfalfa grass forming pellets

An experimental study was conducted to obtain the degree and pattern of influence of the interaction of various test factors on the evaluation indexes of biomass-forming pellets and the optimal combination of test parameters. Poplar sawdust and alfalfa grass were crushed and compressed into pellets, which were used as test samples. The particle size and moisture contents of the biomass raw materials were selected as test factors, and the quality and performance evaluation indexes, such as relaxation density, Shore hardness, water resistance, crush resistance, longitudinal dimensional stability, forming rate, and productivity, were measured for each pellet group. The results showed that for the same biomass raw material, when the particle size range is zero to 1.5 mm and the moisture content is at 15%, the relaxation density, Shore hardness, and forming rate of the formed pellets are the greatest, and the crush resistance, water resistance, and longitudinal dimensional stability are the strongest. When the particle size range is about 4 to 5.5 mm and the moisture content is at 5%, the relaxation density, Shore hardness, and forming rate of the pellets are the smallest, and the crush resistance, water resistance, and longitudinal dimensional stability are the weakest. The best moisture content of the pellets is about 15%.

Research on the Effect and Dynamics of Calcium Oxide on Pyrolysis Behavior of Medium and Low-Rank Coal

With a self-developed laboratory pyrolysis device, the effects of the materials particle size on the yield of Jinjie coal and lime co-pyrolysis products and gas components were investigated. The results shows that the raw material particle size has a significant effect on the coal pyrolysis process. With the decrease of raw material particle size, the tar yield in the pyrolysis product decreases, while the pyrolysis gas yield increases, and the H2 content in the pyrolysis gas increases. As the same time, the temperature distribution and volatiles precipitation rate of materials with different particle sizes were measured, and the macro-reaction kinetic parameters of the co-pyrolysis of coal and lime have been obtained.

Designing the technology and composition of plant extracts using reduced atmospheric pressure

The study aims to establish the regimes and parameters of extraction of bioactive substances from raw plant materials by means of extraction with reduced atmospheric pressure for the purpose of manufacturing non-alcoholic functional syrups. The work is performed by leading specialists of the Kemerovo State University using conventional methods. Preparation of the extracts involves aqueous alcoholic treatment of the crushed mass of raw plant materials selected according to the functional parameters. Extraction is performed in a Soxhlet extractor with an advanced liquid ring vacuum pump. The extraction process is monitored by changes in the content of terpenoids in the extract obtained and the mass fraction of dry matter. As a result, the study establishes the parameters and regimes for carrying out and intensifying the extraction of terpenoids and dry matter from fennel, anise, caraway, and dill: pressure – 0.2 MPa, extraction temperature – 50°С, duration of the process – 45 min, solvent – 40 % aqueous alcoholic solution, raw material particle size – 2-3 mm. These process conditions guarantee the highest degree of extraction of terpenoids and dry matter from raw materials, as well as reduce the time and economic costs.

Effect of Raw Material Particle Size on the Synthesis of La2Zr2O7 by the Molten Salt Method.

In this study, a process based on the molten salt method was proposed to prepare La2Zr2O7 for improving the kinetic conditions of synthesis. Considering that the particle size of raw materials is an important factor that may have an effect on the kinetic process of synthesis, ZrO2 and La2O3 with different particle sizes are used as raw materials, and the synthesis experiment is carried out at 900-1300 °C through the combination of raw materials with different particle sizes. The results show that the particle size of ZrO2 plays an important role in the synthesis of La2Zr2O7. The "dissolution precipitation" mechanism of the synthesis process in the NaCl-KCl molten salt was confirmed by SEM image observation. Furthermore, the influence of the dissolution rate of each raw material on the synthesis reaction was studied by introducing the Noyes-Whitney equation and testing the specific surface area and solubility of each raw material, and it was confirmed that the particle size of ZrO2 was the limiting condition of the synthesis reaction, and use of ZrO2(Z50) with a nominal particle size of 50 nm could significantly improve the kinetic condition of the reaction, thus reducing the synthesis temperature, which can help realize the energy-saving and -efficient synthesis of pyrochlore La2Zr2O7.

Effect of Raw Material Particle Size on the Direct Reduction Process of High-Phosphorus Oolitic Hematite

Effect of Raw Material Particle Size on the Direct Reduction Process of High-Phosphorus Oolitic Hematite

Effect of particle size of calcite on the stacking order of kaolinite during mechanical grinding

AbstractThe effect of calcium carbonate (CaCO3) particles on the stacking order of kaolinite, a layered clay mineral, during the mechanical grinding process was demonstrated by grinding of expanded kaolinite without impurities (Ex‐Kaol), a methoxy‐modified kaolinite, in the presence and absence of calcite with different particle sizes. The X‐ray diffraction patterns of the ground raw materials revealed that the relative intensity of the reflection corresponding to stacking direction of kaolinite decreased in the absence of calcite particles. The presence of calcite particles suppressed the disruption of the stacking order of kaolinite due to the breaking of calcite particles. In addition, this suppression was weakened using calcite particles of smaller size. Meanwhile, the raw ground material containing smaller calcite particles converted into the targeted product faster than the raw ground material containing larger calcite particles. These results indicated that the particle sizes of raw materials are important for solid‐state reactions including kaolinite.