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The fusion of the circular economy and industrial symbiosis has several advantages from an economic and developmental standpoint. Cooking energy security issues in Africa can partly be solved by the utilization of waste resources in energy technology decisions such as briquette. However, one of the limitations associated with waste-based briquettes has been identified as a reduction in efficiency when stored for a long period of time under varied storage conditions. The aim of this study was to ascertain the effects of storage time and exposure on the calorific value and mechanical characteristics of a waste-based composite briquette made from oil palm shell and decanter cake after 180 days of storage. The calorific value decreased by 12.99% and 31.40%, respectively, for sealed packaged storage and open-air storage. On the 180th day of the experiment, the packaged storage and the open-air storage registered 1000.48 kg/m3 and 870 kg/m3, 72.34% and 100%, 712% and 895%, and 118% and 143% for relaxed densities, shatter indices, resistance to impact, and hygroscopic properties respectively. Manufacturers within West Africa can adopt the findings in this study as a guide for their processes. [ABSTRACT FROM AUTHOR]

Background: Uganda's energy relies heavily on biomass sources. This dependence on biomass for household and commercial purposes, driven largely by population increase, poses pressure on natural resources, such as forests. This study investigates the usage of some of the country's largely produced agricultural wastes for the production of biofuels. Methods: Pineapple peels (PP), banana peels (BP) and water hyacinth (WH_Eichhornia crassipes (Mart.) Solms) were used for generation of both carbonized and uncarbonized briquettes. Physical properties and calorific values for the developed briquettes were determined through thermogravimetric analysis and using a bomb calorimeter. Results: Pineapple peel carbonized briquettes had the highest calorific value (25.08 MJ/kg), followed by a composite of banana peels and pineapple peels (22.77 MJ/kg). The moisture content for briquettes ranged from 3.9% to 18.65%. Uncarbonized briquettes had higher volatile matter (ranging between 62.83% and 75.1%) compared to carbonized briquettes (ranging between 22.01% and 24.74%). Uncarbonized briquettes had a shorter boiling time (ranging between 27 and 36 min for 2.5 L of water) compared to carbonized briquettes (ranging between 26 and 41 min). Bulk density was highest in uncarbonized BP briquettes (1.089 g/cm3) and compressive strength was highest with carbonized BP + PP (53.22 N/mm2). When using water hyacinth alone, the produced carbonized briquettes show low calorific values (16.22 MJ/kg). However, the calorific values increased when they were mixed with banana (20.79 MJ/kg) or pineapple peels (20.55 MJ/kg). Conclusions: The findings revealed that agricultural wastes could be used to augment the energy sources pool to protect the environment and create social stability in the community. [ABSTRACT FROM AUTHOR]

In energy scarcity, particularly in Agri-based developing economies, bio-coal briquetting is the most suitable means of meeting sustainable energy needs utilizing agricultural waste. In this study, briquettes were made from an indigenously designed briquetting machine for investigating coal–biomass proportion blend using coal from Dara Adam Khel, Khyber Pakhtunkhwa in Pakistan, and pomegranate/olive waste to analyze their resulting calorific value, strength, and geochemical properties. A central composite design (CCD) and response surface methodology (RSM) were employed to design the experiments and analyze the data. Regression models were developed for each biomass type, demonstrating their adequacy and reliability for further analysis and prediction. Energy Dispersive X-ray Spectroscopy (EDX) analysis provided insights into the elemental composition of the coal briquettes. Mechanical analysis was performed to assess the strength of the briquettes, with varying compositions showing different levels of strength. Optimization using a composite desirability function yielded an optimal calorific value of 6728 kJ/kg. In summary, this study underscores the viability of bio-coal briquetting as a transformative solution to alleviate energy scarcity. Repurposing agricultural waste curtails resource depletion while mitigating waste disposal challenges. The optimized calorific value aligns with eco-friendly energy initiatives, advancing a greener path toward energy security. [ABSTRACT FROM AUTHOR]

In Indonesia, palm shells and plastic waste are quite abundant, and they have the potential to cause environmental pollution. Additionally, the availability of fossil fuels is dwindling, so other energy sources are needed. This study aimed to find a solution to these problems. In this study, briquettes based on dried palm shells (cangkang kelapa sawit or CKS) with the addition of polypropylene (PP) and polyethylene (PE) plastics were prepared and characterized. The briquettes were made using cassava starch adhesive, and the densification was carried out at a pressure of 1283.40 N/m² for 30 min. The briquettes were made with varying amounts of plastic added to the mixture: 1, 2, 3, and 4 % (w/w % of CKS). The produced briquettes were analyzed for their calorific values and mechanical compression properties. Calorific value is an important parameter related to the energy content of briquettes as fuel. A compression test is important since the briquettes must resist external compression load due to stacking during storage and transportation. The calorific values of the briquettes obtained from the experiments were found to be in the range of 27.14-27.7 MJ/kg, wherein the calorific value for briquettes containing PP is higher than that of the ones containing PE. From the compression testing, it was found that the higher the plastic content, the higher the compression modulus of elasticity and ultimate strength of the briquettes. As with the calorific values, the modulus of elasticity, and ultimate strength value of briquettes containing PP are higher than that of the ones containing PE with the same palm-to-plastic ratio. [ABSTRACT FROM AUTHOR]

Briquetting is needed to complete the upgrading process of low-rank coal, which commonly produces yield in a powder form. The process increases solid fuel's energy density, handling, and transportability. The binderless briquetting is frequently selected over the conventional briquetting process since it utilizes the coal substance to bind the particle such that the coal property as fuel is unaltered. Unfortunately, the mechanism of how the coal particles are bonded remains unclear. This research investigated the binderless briquetting process at room temperature (cold binderless briquetting), employing moisture content (MC) as a binding agent. Experimental results show that, during the compaction process, the moisture acts as lubricants and provides deformability in the coal particle, which eases the particle interlocking at a higher density. However, the change of moisture in the briquette after the compaction process could induce swelling and shrinkage in the particle, causing a discrepancy in the particle interlocking system and reducing the briquette strength. From the investigation, the cold binderless briquetting of LRC is recommended to be conducted at 2500 bar compaction and using coal particles with the initial MC of 10–20%. The prediction of briquette strength at different moisture content is also proposed in this paper. [ABSTRACT FROM AUTHOR]

A sequential two-step thermochemical process was studied for spent green tea waste (SGTW), involving an initial pyrolysis step followed by thermal or catalytic cracking. This process was carried out in two bench-scale reactors (fixed bed reactor and tubular reactor) serially coupled. At a fixed pyrolysis temperature of SGTW (550 °C), the application of high cracking temperatures (700 and 800 °C) positively affected both the yield and composition of the gas product. Consequently, it has the potential to be used for the production of diverse biofuels and chemicals, or to be partially recycled to optimize the process efficiency. Moreover, the use of inexpensive catalysts, particularly dolomite, was considered advantageous, since the syngas yield (56.5 wt%) and its potential were greatly enhanced, reaching a H2/CO ratio of 1.5. The homogenous biochar obtained, with a calorific value of 26.84 MJ/kg, could be harnessed as good-quality fuel for briquette applications and as a biofuel source for generating stationary power. Furthermore, catalytic cracking pyrolysis was examined for different types of coffee waste, revealing that this process is a simple and clean solution to valorize oxygen-rich lignocellulosic biomass and generate valuable gaseous by-products. [ABSTRACT FROM AUTHOR]

This research provides the results of large-scale laboratory and industrial tests on silicon electrothermy with silicon carbide and briquettes with quartz sand and petroleum coke added to the charge. It is shown that only replacement of petroleum coke for these ingredients in a standard charge is efficient. Substituting coal for them also deteriorates the process efficiency, which is explained by increased electrical conductivity of the charge. Recommendations to improve the electrothermy technology, including SolG Si preparation are formulated. [ABSTRACT FROM AUTHOR]

Copyright of Misr Journal of Agricultural Engineering is the property of Egyptian National Agricultural Library (ENAL) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Oil palm waste in the South West Aceh, Indonesia region, has the potential for renewable energies to replace fossil energy. On the basis of previous studies, the mixture of EFB, fiber and shells into bio-try briquettes had an average calorific value of 5000 calories per gram. In this study, the authors explored the potential of bio-try briquettes. Especially for the South West Aceh (Barsela) Region, a Bio-try briquette can generate electricity of 586.152 GWH, meet electricity consumption in Barsela of 584.57 GWH, and electricity surplus of 1.582 GWH. On the basis of the economic feasibility analysis, it was demonstrated that the Internal Rate of Return (IRR) is 22.58%, which surpasses the set interest rate of 12%, the net profit (NBC ratio is 34.39 > 1), and the principal return point (BEP) is below 1 year (< 0.034 years). As for the environmental aspect, the solid waste used can be reduced by 10.94% or 100800 tons per year. The environmental impact caused by the presence of bio-try briquette on the global warning potential (kg CO2 eq) or greenhouse gases on the third mixture of waste is 77,000 kg per day or 77 tons per day. [ABSTRACT FROM AUTHOR]

The resource utilization of agricultural and forestry wastes is of great significance for low-carbon environmental protection and the transformation of China's energy structure. The way of the fuel utilization of agricultural and forestry wastes was introduced in this paper, and the molding process of biomass solid briquette was summarized. The research status of the factors affecting the briquetting quality and the binders used in the carbonization briquetting and other fields were also discussed. The development trend of the performance of biomass solid briquettes was prospected, and the existing problems of biomass solid briquettes were pointed out and suggestions for improvement were also put forward. [ABSTRACT FROM AUTHOR]

Coal and gas outburst mainly occurs in tectonically deformed coal (TDC). TDC has low strength and is difficult to core; thus, it is often replaced by briquette coal (BC) for research. However, whether the fracture and permeability in BC are consistent with TDC remains to be verified. This study used X-ray computer tomography to characterize the fracture of TDC and BC and further explored the difference of permeability between them through the triaxial permeability experiment and lattice Boltzmann method (LBM) simulation. The results showed that TDC has strong heterogeneity and developed mostly complex fracture systems with large apertures. The fractures are primarily flat with disorderly directions, slightly poor connectivity, but strong connection strength. However, BC is formed by the accumulation of particles and exhibits micro-fractures with good homogeneity, which are mostly tube and slit with good connectivity but weak connective strength. During the stress loading process, the permeability of TDC showed a three-stage (i.e., sharp → rapid → steady) declining trend, while the BC had a two-stage (i.e., sharp → rapid) decline. The fracture compressibility of TDC decreased first and then increased with the increase in stress, exhibiting mostly plastic deformation, while the fracture compressibility of BC is far less than that of TDC, exhibiting mostly elastic deformation. Moreover, the average permeability damage and irreversible permeability damage rates of TDC were 0.0133 mD (1 mD = 1 millidarcy = 9.869233−16 m2) and 52.56%, respectively, which were higher than those of BC. Therefore, a new digital rock physics method based on X-ray CT and LBM technology is proposed to study the fracture and permeability. [ABSTRACT FROM AUTHOR]

To study the influence of different excess air coefficient (α) on the layer combustion characteristics of biomass briquettes, the typical corn straw pellet fuel in the main grain production areas in Northeast China was used as the research object, and a fixed-bed test rig for biomass pellets was built to simulate of the combustion process of biomass pellets along the height of the furnace and moving direction of the grate, 25 sets of combustion tests under 5 working conditions of 30, 40, 50, 60 and 70 Nm3·h-1 were carried out, respectively. The test data was collected by the patrol instrument, and the collection step length was 1 min. The collected data was processed and analyzed by methods such as matrix and polynomial fitting. The test results indicated that when the primary air flow (Qao) was not less than 50 Nm3·h-1, the ignition delay time (td), flame downward propagation rate (Rf) and fuel content in ash (ηa) decreased with the increase of Qao. As Qao was less than 50 Nm3·h-1, td, Rf, and ηa increased with the increasing of Qao. In the combustion zones of 200~150 and 100~50 mm, Rf showed a trend of decreasing and then increasing. In the combustion zone of 150~ 100 mm, when Qao was not more than 40 Nm3·h-1, Rf increased with the increasing of Qao, and then as Qao was more than 40 Nm3·h-1, Rf tended to be stable. It was found that when Qao was 50 Nm3·h-1 (α was 1.163), td was 3.34 min, and the combustion temperature was higher and the time was shorter (about 45 min) than other Qao, and ηa was 0.71%, the layer combustion characteristics were more ideal than other conditions. [ABSTRACT FROM AUTHOR]

This research systematically evaluates a biomass combustion furnace, focusing on the influence of varying combustion chamber casing materials. The study employs controlled laboratory experiments to investigate the impact of different casing materials on combustion performance, thermal efficiency, and practical applications such as water boiling capacity. The research uses distinct materials, including clay, steel, and aluminum, for combustion chamber casings while maintaining consistent dimensions. The central experimental apparatus, an aluminum stove, was meticulously crafted, adhering to precise measurements. Coconut shell briquettes served as the primary fuel source for this investigation. The results reveal intriguing dynamics in combustion behavior. Notably, the choice of combustion chamber casing material significantly affects fire temperature, sleeve wall temperature, thermal efficiency, and the ability to boil water. Clay emerges as a standout performer, achieving high thermal efficiency (56.8 %), substantial water boiling capacity (25 liters), and efficient fuel consumption (1.28 kg of burnt briquettes). However, steel casing materials excel in generating the highest fire temperatures (up to 557 °C), underscoring their exceptional heat-conducting properties. Aluminum has fast temperature responses but may not retain heat like clay. The findings help optimize biomass combustion furnaces and associated applications. Material selection is crucial to attaining combustion goals like efficiency, temperature generation, or practical heat. These discoveries could lead to more efficient and ecologically friendly biomass combustion systems for sustainable energy and resource use [ABSTRACT FROM AUTHOR]

This paper presents a theoretical evaluation of the prices of mixed briquettes produced from coconut shells (CCS), banana peels (BNP), rattan waste (RWT), and sugarcane bagasse (SGC) and, on the other hand, an analysis of the economic viability of their use as a replacement for conventional household fuels (liquefied petroleum gas, fuelwood, and wood charcoal) in households in Cameroon. The investigation was carried out using the life cycle cost method on a typical household over a ten-year period with annual cooking energy requirements of 950 kWhth. The SGC–CCS and SGC–RWT mixed briquettes with ratios higher than 7.75% and 11.1%, respectively, have prices lower than EUR 0.063/kWhth. The Present Value of the Net Benefit is positive for the use of SGC–CCS and SGC–RWT mixed briquettes. The results show that by making the right mixes of residues, it is possible to obtain biomass briquettes that are less expensive than conventional fuels. [ABSTRACT FROM AUTHOR]

This study presents for the first time the efficiency of using vortex layer apparatuses (VLAs) for de-oiling of scale and dezincification of sludge to enable their use as components of briquettes without any health risks or compromising the integrity of the blast-furnace lining. The effect of several intense physical and mechanical processes in the VLA, induced by a rotating magnetic field, leads to the grinding of particles of the processed material, thereby modifying its structure and properties. The treatment of the oiled scale in VLA enables oil removal (down to 0.01%) while obtaining the oil as a by-product. A VLA can be used to reduce the duration of the zinc leaching process to 30 min, and selectively recover iron and zinc oxides to a final content of up to 0.09% and 0.043% by weight, respectively, in the non-recoverable sediment. Therefore, the material composition of the samples of oiled scale and the scale processed in a rotating magnetic field was studied, and the possibility of using VLA to activate binders for briquetting is presented. Furthermore, schemes for the industrial implementation of technologies for de-oiling and dezincification of materials in VLA are proposed in this study. [ABSTRACT FROM AUTHOR]

Results are provided for experimental-industrial tests of high-carbon ferrochrome smelting with partial replacement of the basic chromium ore with chromium ore briquettes produced by OJSC Donskoi Ore Mining and Processing Plant in an amount of 20–40% of the chromium ore raw material supplied to TNC Kazchrome JSC Aksu Ferroalloys Plant (Kazakhstan). These tests show that use of chromium ore briquettes has a number of technological advantages. When using briquettes instead of ore, there is a reduction in electricity consumption from 7201 to 6184 kWh/ton, and chromium extraction increases from 80.3 to 85.3%. Use of briquettes solves the problem of involving substandard chromium ore raw materials in production and improving technical and economic performance of the furnace. [ABSTRACT FROM AUTHOR]

The heat treatment of nutshells, followed by the densification of its biochar particles, can be used as a process to improve its quality for use as a solid fuel. In this study, Taguchi method, gray relational analysis (GRA), and analysis of variance (ANOVA) were used to elucidate the effect of compressive force, particle size, and binder content on physical properties of biochar briquettes produced from nutshells, they were also used to determine the optimum conditions of compressing the fuel briquettes. The percentage contribution of each controllable factor was also determined. The solid fuel briquettes were produced by compacting the mixture of the ground biochar and the binder (molasses) at ambient temperature, using a piston and mold process. The results showed that the obtained biochar has a good fuel quality; the amount of binder is the most influent parameter; and that the energy briquettes obtained under the optimal conditions (compressive force of 112 MPa; binder amount of 40%; particle size <200 µm) present a high density, high calorific value, and a good compressive strength. [ABSTRACT FROM AUTHOR]

Strict environmental regulations have made on many industrial sectors to try and reduce CO2 gas production, including the nickel and ferronickel manufacturing industries. One of the promising technologies in reducing CO2 emissions is carbothermic reduction using a lower operating temperature than smelting process. This study aims to study the effects of adding and laying reductant (coal) on composite briquette. By using the same C/O molar ratio, this research tries to study the effects of inner and outer coal on the carbothermic reduction of laterite nickel ore. The carbothermal reduction process was carried out at 700 °C for 2 h and then followed by heating at 1400 °C for 6 h. Then, the ferronickel was separated from the impurities by magnetic separation. Several tests and calculations were carried out to assess process performance, such as energy dispersive X-ray, scanning electron microscope, X-ray diffractometer, calculation of nickel recovery, calculation of selectivity factor, and calculation of separation efficiency. The result showed that inner and outer coal in the carbothermic reduction process of laterite nickel ore can affect the selectivity performance of nickel. The best nickel recovery (93%) was obtained when using 70% inner coal and 30% outer coal. On the other hand, the best nickel content (13.99%) was achieved when using 90% inner coal and 10% outer coal. The ferronickel product obtained from this process can be applied as a raw material in stainless steel making or further processed into nickel sulfate powder. [ABSTRACT FROM AUTHOR]

Around 25 million tons of coal mine waste rock (CMWR) are stored in many places in Morocco due to coal mining activities. As a result, air and water quality of the neighborhood is polluted and large lands are occupied. This study aimed to investigate the use of an integrated and circular approach based on coal recovery and waste rock recycling. More than 30 drill core samples were taken from the big coal dump reaching a depth of 60 m and analyzed to evaluate the chemical composition variability. Froth flotation was used to recover coal particles using diesel as a collector and Methyl Isobutyl Carbinol as a frother, 100 g/t each. The tailings of coal flotation process (CFT) were used to manufacture fired bricks at a pilot scale. The results of this study highlighted the possibility to valorize the whole waste material toward an objective of zero waste in the future. On a basis of 100t feed, (i) 10-15t can be recovered as high-quality anthracite coal with a calorific value over 7500 kcal/kg using flotation processing at a recovery yield over 80%, (ii) 45-60t can be reused as shales for bricks production with a compressive strength over 16MPa, (iii) 20-30t can be reused as aggregates for concrete production with a compressive strength over 20MPa. The remaining material can be reused as sand. The recovered anthracite can be reused to manufacture coal briquettes or used at it is in the thermal power plant next to the dump site. [ABSTRACT FROM AUTHOR]

Conversion of shea butter shell charcoal to briquettes solid fuel is a means to reduce environmental pollution. This study investigated the potential of converting shea butter shell char to briquettes with cassava starch solution. The shell was pretreated and carbonized at temperature of 450 °C for 45 min in a furnace. Five briquette samples were produced with constant weight mass of char and different masses of cassava starch binder was varied as 10 %, 30 %, 50 %, 70 % and 90 %. The briquettes produced were analyzed for moisture content, bulk density, shatter index, water resistance, calorific value and compressive strength. The effect of the different binder contents on quality of the briquette samples was also investigated. The result revealed moisture content varied from 9.12 % to 14.83 % and density varied from 0.61 g cm-3 to 0.85 g cm-3. The water resistance of the briquettes increased from 40.7 % to 75.5 % and shatter index increased from 71.7 % to 92.1 %., while compressive strength values ranged from 18.63 MPa to 24.46 MPa. The calorific values of the briquettes in their increasing amount of binder were found to be between 16.94 and 22.33 MJ/kg. The briquette with the highest amount of binder had compressive strength of 24.46 MPa and calorific value of 22.33 MJ/kg. The results showed the conversion of sheabutter shell to briquette can serve as an effective technique to bringing value and use to biomass wastes. [ABSTRACT FROM AUTHOR]

The particle size distribution of woodworking residues influences the quality of the biofuels made of these materials. Hence, it is essential to investigate the fractional composition of raw materials for pellet production. Tested materials originated from ten parquet manufacturing facilities located in western Poland. The research material consisted of uncontaminated oak (Quercus spp.) wood particles. The tested material had a moisture content ranging from 8.8% to 11.4% and a density of 210.7 ± 1.79 kg/m3. A sieve analysis method segregated the tested material into four distinct size fractions (<1.0 mm, 1.0-2.5 mm, 2.5-5.0 mm, and >5 mm). The average mass shares in these fractions were 53.72 ±0.51%, 35.14 ±0.27%, 9.59 ±0.36%, and 1.55% ±0.11%, respectively. The particle size distributions of wood particles generated in all the facilities demonstrate remarkable similarity. No substantial differences were observed in terms of tilt angle and calorific value. Factors such as variations in raw material species, geographical origins, density, humidity, and technological processes appear to have minimal influence on the sieve-size distributions of the generated sawdust. All these solid wood processing residues can undergo processing into high-quality solid biofuel production. [ABSTRACT FROM AUTHOR]

Briquetting is considered one of the pre-treatment methods available to produce raw materials of uniform size and moisture content that are easy to process, transport, and store. The quality of briquettes in terms of density and strength depends on the physical and chemical properties of the raw material and the briquetting conditions. However, determining briquette quality is difficult, very costly, and requires long laboratory studies. In this paper, an easy, inexpensive, and fast methodology based on machine learning for the determination of quality parameters of briquette samples is presented. Compressive resistance, one of the most important briquette quality parameters, was estimated by machine learning methods, considering particle size, material moisture, applied pressure value, briquette density, shatter index, and tumbler index. Extra Trees, Random Forest, and Light Gradient Boosting regression models were used. The best estimate is seen in the Extra Trees regression model. The R2 and MAPE values are 0.76 and 0.0799, respectively. [ABSTRACT FROM AUTHOR]

The present work studies the convective drying of a granular porous medium in a bed of olive pomace. The experimental tests were conducted in a closed convection drying loop of hot air. The experimental tests measured the mass loss over time. Tests were carried out for five temperature values: 60 ± 0.1 °C, 70 ± 0.1 °C, 80 ± 0.1 °C, 90 ± 0.1 °C and 100 ± 0.1 °C, respectively. Moreover, three values of velocities of the drying air, 1 ± 0.01 ms−1, 1.5 ± 0.01 ms−1 and 2 ± 0.01 ms−1, were considered. The effects of initial humidity, bed thickness and pomace composition on the drying process were studied. The results show that the moisture content decreases when the temperature and the velocity of the drying air increase. In addition, the composition of olive pomace (pulp, pits and raw pomace) significantly affects the drying time. A characteristic drying curve and its equation were determined. Seven thin layer drying models were tested, and the Midilli et al.'s model produced the best agreement. The effective moisture diffusivity coefficient (Deff), the activation energy (Ea) and the pre-exponential coefficient of the Arrhenius law were evaluated. The results could be of great help for the pretreatment of crude olive pomace when moving to industrial scale and before passing to the step of biofuel (pellets, briquettes or logs, Syngas) production. [ABSTRACT FROM AUTHOR]

Producing biomass briquettes from industrial solid wastes is a more environmentally friendly way to provide alternative energy and is essential for Ethiopia to satisfy its growing energy needs while also ensuring efficient waste management in the expansion of industrial parks. The main objective of this study is to produce biomass briquettes from a mixture of textile sludge and cotton residue using avocado peels as a binder. Textile solid waste, avocado peels, and sludge were dried, carbonized, and turned into powder to make briquettes. Briquettes made from the mixture of industrial sludge and cotton residue were combined in various ratios: 100:0, 90:10, 80:20, 70:30, 60:40, and 50:50 with the same amount of the binder. Briquettes were then made using a hand press mold followed by sun-drying for two weeks. The moisture content, calorific value, briquette density, and burning rate of biomass briquettes ranged from 5.03 to 8.04%, 11.19 to 17.2 MJ/kg, 0.21 to 0.41 g/cm3, and 2.92 to 8.75 g/min, respectively. The results revealed that the briquette produced from a 50:50 ratio of industrial sludge to cotton residue was the most efficient. The inclusion of avocado peels as a binder enhanced the briquette's binding and heating properties. Thus, the findings suggested that mixing various industrial solid wastes with fruit wastes could be an effective means of making sustainable biomass briquettes for domestic purposes. Additionally, it can also promote proper waste management and provide young people with employment prospects. [ABSTRACT FROM AUTHOR]

The development and utilization of wood briquettes is one of the efforts to reduce dependence on fossil fuels, including to fulfill overseas market need. This study aimed to evaluate the properties of wood briquettes made of the branches of three mangrove species and to analyze the effect of different wood species of mangrove branches, and the types of starch adhesive, on the quality of wood briquettes. The wood briquettes made in this study were 3 cm × 4 cm in a cylindrical shape using three wood species of mangrove branches, namely mata buaya (Bruguiera sexangula), buta-buta (Excoecaria agallocha), and bakau minyak (Rhizophora apiculata), while the adhesives used were tapioca starch, maize starch, and potato starch. The results showed that the moisture, ash content, and calorific value of the wood briquettes mostly met the ISO 17225-3:2-2020 class A2 standard and the specification and quality standards of wood briquettes for Grade A2 issued by the Korea Forest Research Institute, except the density. Wood briquettes made of mata buaya by using the three types of starch adhesives generally had better properties than all other types of wood briquettes. The interaction of mangrove wood species and the types of starch adhesive had a significant effect on the properties of wood briquettes, except for volatile matter and calorific value for which they had no significant effect. The use of wood briquettes from mangrove wood branches contributes to sustainable forest management and maintains the ecological function of mangrove forests while providing environmentally friendly alternative energy for households as a source of fuel/energy. Furthermore, future research is needed, such as investigating the optimal pressing pressure needed to achieve higher density of the wood briquettes. [ABSTRACT FROM AUTHOR]

The reduction kinetics of cold‐bonded briquette prepared from return fines of sinter is studied. The results reveal that cold‐bonded briquettes with coke (CBBC) have a higher reduction velocity index (RVI) value than cold‐bonded briquettes without coke (CBB). Interfacial chemical reaction controls the early stages of the CBB reduction process at 900 and 950 °C, followed by both interfacial chemical reaction and internal diffusion. At 1000, 1050, and 1100 °C, the early and final stages of the CBB reduction process are controlled by interfacial chemical reaction and internal diffusion, respectively, while both interfacial chemical reaction and internal diffusion control middle stage. The apparent activation energies of the different stages are 46.20, 56.74, 38.24, and 40.74 kJ mol−1, respectively. The gasification of carbon reaction controls the reduction process of CBBC, and the apparent activation energy is 32.42 kJ mol−1. According to the Friedman method, the apparent activation energy of CBB and CBBC is reasonable. Coke promotes the phase transformation in CBBC. Scanning electron microscopy results show that the CBBC sample is more fully reduced than the CBB sample and that it has smoother corners and edges of the iron‐bearing phase or the metallic iron phase than the CBB sample. [ABSTRACT FROM AUTHOR]

Copyright of Coal Science & Technology (0253-2336) is the property of Coal Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)