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Copyright of Nonferrous Metals (Mineral Processing Section) is the property of Beijing Research Institute of Mining & Metallurgy Technology Group 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.)

This study aimed on the production and characterization of biochar derived from pebble-sized coconut shells, exploring its potential as an alternative fuel source. The pebble-sized material study is crucial for large-scale applications and real-world conditions. While smaller material sizes may offer efficiency in certain aspects, testing with pebble-sized offers a comprehensive understanding of how the pyrolysis process and biochar quality will perform in practical situations. Coconut shells, a widely available agricultural waste, were processed into pebble-sized feedstock and subjected to pyrolysis under controlled conditions. Practical and inexpensive thermal processes were performed at five various temperatures, starting at 250°C to 450°C to achieve the quality of expected produced biochar. A consistent temperature increase of 10°C per minute and a holding period of 120 minutes was applied at each run. The resulting biochar was characterized using GC-MS techniques analysis to assess its physical and chemical properties. The findings demonstrate that biochar produced from pebble-sized coconut shells exhibits promising characteristics, including high carbon content, low moisture, and a stable structure, making it a viable candidate for use as a sustainable and eco-friendly solid fuel. The biochar produced has an average moisture content of 3.98%, ash content of 2.89%, volatile content of 18.56%, fixed carbon content of 78.53%, and a heating value of approximately 28.56 MJ/kg. It is concluded that biochar from pebble-sized coconut shell material can be an essential ingredient in briquettes, serving as an alternative solid fuel. This research contributes to the growing interest in converting agricultural residues into valuable energy resources, offering a potential solution for reducing dependence on conventional fossil fuels and ultimately contributing to mitigating pollution due to biomass waste.

This study aimed on the production and characterization of biochar derived from pebble-sized coconut shells, exploring its potential as an alternative fuel source. The pebble-sized material study is crucial for large-scale applications and real-world conditions. While smaller material sizes may offer efficiency in certain aspects, testing with pebble-sized offers a comprehensive understanding of how the pyrolysis process and biochar quality will perform in practical situations. Coconut shells, a widely available agricultural waste, were processed into pebblesized feedstock and subjected to pyrolysis under controlled conditions. Practical and inexpensive thermal processes were performed at five various temperatures, starting at 250 °C to 450 °C to achieve the quality of expected produced biochar. A consistent temperature increase of 10 °C per minute and a holding period of 120 minutes was applied at each run. The resulting biochar was characterized using GC-MS techniques analysis to assess its physical and chemical properties. The findings demonstrate that biochar produced from pebble-sized coconut shells exhibits promising characteristics, including high carbon content, low moisture, and a stable structure, making it a viable candidate for use as a sustainable and eco-friendly solid fuel. The biochar produced has an average moisture content of 3.98%, ash content of 2.89%, volatile content of 18.56%, fixed carbon content of 78.53%, and a heating value of approximately 28.56 MJ/kg. It is concluded that biochar from pebble-sized coconut shell material can be an essential ingredient in briquettes, serving as an alternative solid fuel. This research contributes to the growing interest in converting agricultural residues into valuable energy resources, offering a potential solution for reducing dependence on conventional fossil fuels and ultimately contributing to mitigating pollution due to biomass waste. [ABSTRACT FROM AUTHOR]

Coal is the most valuable gasification resource due to its abundance and low cost for commercial applications. But utilization of low-rank Indian coals for gasification is challenging due to difficulty in washing. For utilizing low-grade high ash raw coal, blending is one of the effective methods to control the gasification performances. So, the present study explores the gasification of such a low-rank raw coal blend and compares the results with washed coal blend. The blending effects on raw gas yield (kg/kg of coal) and heating value (Kcal/Nm3) were investigated for coal blends-WH (washed coal with high-rank coal) and RH (raw coal with high-rank coal). In WH, raw gas yield is 1.210 to 1.225 (kg/kg of coal), whereas, in RH is 1.189 to 1.213 (kg/kg of coal), though the fixed carbon content of WH (40.75–41.74%) is lower than RH (44.73–45.25%). In washed coal, raw gas yield is minimum (0.75 kg/kg of coal). The heating value is lower in WH (2730–2871 Kcal/Nm3) than in RH (2884–2978 Kcal/Nm3). Statistical correlation is developed between gaseous components of raw gas and heating value; H2/CO ratio is the most significant parameter. RH gasification is economically viable than WH. [ABSTRACT FROM AUTHOR]

Coal gangue (CG), a byproduct of coal mining, integrated with polyethylene (PE) offers potential in diverse applications. However, ensuring compatibility between CG and PE remains a challenge due to CG's complex nature. This study explores the influence of fixed carbon, represented by high‐carbon‐content anthracite, on the interface of CG/PE composites. Comprehensive investigations were conducted on physical, mechanical, thermal, microstructural, and chemical aspects. Results revealed that increasing carbon content positively impacted density and hardness while enhancing bending strength and modulus, albeit at a cost of reduced tensile strength. When the C content reached 80%, the hardness and density increased from 50.5 HD and 0.93 g cm−3 to 62.4 HD and 1.18 g cm−3, which were 23.6% and 26.9% higher, respectively. Meanwhile, the bending strength and bending modulus reached 17.2 and 1582.4 MPa, which were 53.6% and 239.1% higher than those of the composites prepared from pure PE (11.2 and 466.7 MPa), respectively. However, the tensile strength decreased by 48.7% from 11.7 to 6.0 MPa. Moderate carbon content positively affected thermal stability, yet higher concentrations posed stability challenges. Microstructural analyses unveiled varied interfacial morphologies, shedding light on carbon's role in enhancing material rigidity and hardness. Surface chemical studies suggested physical entanglement between carbon and PE. Additionally, varying carbon content influenced crystallization, elevating crystallinity and impacting mechanical properties. The findings underscore carbon's potential in reinforcing composite materials. This research provides insights into optimizing CG/PE composites and addressing CG treatment challenges. Highlights: Unveiled relationships between fixed carbon and properties in composites.The structure was studied qualitatively and quantitatively by XRD.The anthracite‐C substitution in composite preparation was unraveled. [ABSTRACT FROM AUTHOR]

This study addresses the effects of densification at varied pelletization temperatures on the novel Malaysian Khaya senegalensis wood-derived pellets biomass fuel characteristics. The lack of comprehensive understanding regarding the biomass fuel characteristics of this species prompted the research. By addressing this knowledge gap, this study explores the impact of temperature variations on key fuel properties, contributing to the optimization of sustainable biomass fuel production in manufacturing and materials processing. Khaya senegalensis wood, grown and harvested in Malaysia, was pelletized at different temperatures to analyze the calorific value, volatile matter content, ash content, fixed carbon, bulk density, and moisture contents of the pellets. The experimental data revealed a significant relationship between temperature and these fuel properties. Pelletizing at 75 °C produced the highest calorific value of 19.47 MJ/kg and the maximum fixed carbon content of 10.04%. A low ash level of 4.26% was achieved via pelletizing at 75 °C. According to the results, 75 °C produced the best thermophysical properties. These findings provide valuable understanding of how pelletization temperature influences fuel pellet thermophysical properties, a critical aspect in optimizing fuel pellet production, storage, advancing renewable energy resource utilization, and, finally, promoting a cleaner and more sustainable energy future. [ABSTRACT FROM AUTHOR]

The increasing demand for sustainable energy solutions has driven interest in the utilization of agricultural residues, such as coconut shells, for bio-briquette production. This study investigates the impact of binder types (cassava and corn) and concentrations (5 wt%, 10 wt%, 15 wt%) on the properties of bio-briquettes made from dried coconut shells with two particle sizes (40 mesh and 60 mesh). The experimental evaluation focuses on several performance indicators, including density, shatter index, percentage moisture content (PMC), percentage volatile matter (PVM), percentage ash content (PAC), percentage fixed carbon (PFC), higher heating value (HHV), ignition time, burning time, and boiling time. The results indicate that briquettes with 10 % fine charcoal cassava binder achieved the highest density of 0.764 g/cm³ due to improved compaction. Briquettes with 15 % coarse charcoal corn binder demonstrated the highest shatter resistance at 96.99 %, reflecting their superior structural integrity. The highest PMC and PVM values were observed in briquettes with 15 % coarse charcoal cassava binder, at 8.13 % and 31.25 %, respectively. Conversely, the highest PAC was 16.34 % for 5 % coarse charcoal cassava binder. Briquettes with 10 % fine charcoal corn binder exhibited the highest PFC of 70.79 % and HHV of 31.51 MJ/kg. Boiling times ranged from 15 min 53 s to 36 min 35 s, with the shortest boiling time for briquettes with 10 % fine charcoal corn binder. The findings highlight the superior mechanical properties and energy performance of bio-briquettes with specific binder concentrations and particle sizes. This study demonstrates the potential of coconut shell bio-briquettes as a viable and sustainable energy source, offering economic and environmental benefits through the effective utilization of agricultural waste and reduction of carbon emissions.

Palm kernel shell is solid waste produced from the processing of crude palm oil (CPO). In this context, phosphoric acid (H3PO4) serves as an essential activator for producing an adsorbent with maximum micropore under operating conditions at a temperature of

Briquetting technology became one appropriate method that can be used to convert biomass waste into a renewable energy source. Sources of biomass raw materials that have promising potential are pine sawdust and coconut shell waste. Sawdust has potential for about 0.78 million m3/year and coconut shell waste around 360 thousand tons/year. The research aim was to analyse the effect of the carbonization temperature to volatile matter and fixed carbon of briquette. The research was done by variating carbonization temperature at 400 oC, 500 oC, and 600 oC. The result showed that at carbonization temperature of 400 oC, the volatile matter and fixed carbon was 42.28% and 55.74%. The volatile matter and fixed carbon are 43.19% and 54.96%, found at carbonization temperature 500 oC. The highest fixed carbon 55.98% and the lowest volatile matter 42.19% was found from carbonization temperature at 600 oC. The carbonization temperature in briquetting process affects the volatile matter and fixed carbon of briquette.

This work aimed to observe the influence of calorific value and proximate properties in the fabrication of rice husk (RS) and coffee shell (CH) briquettes composite. Rice and coffee husks contain cellulose, hemicellulose, and lignin. These contents are necessary for the adhesive to bind the briquette (amylose and amylopectin). The raw materials were carbonized at 400 oC for 60 minutes. Variations of sieving size (60, 80, and 100 mesh) and the composition ratio of raw material CH: RS were reviewed to study their effect. Tests of density, moisture content, volatile matter content, ash content, fixed carbon content, shatter index, combustion rate, and calorific value were carried out to determine the optimum composition. The results were obtained with the best quality at a particle size of 60 mesh with the highest calorific value of 17.422 MJ/Kg. It showed that the briquettes have good quality and are comparable with the standard briquette.

Charcoal is the most preferred energy source in Mozambique and contributes to income generation for most households and small-medium scale commercial entities. However, charcoal production contributes to the illegal exploitation and rapid decrease of natural forest cover. Attempts from the government to address this challenge by implementing energy plantation projects using Eucalyptus spp. have failed due to local communities' preference for charcoal produced from native wood species. Therefore, this study aims at evaluating the combustibility of charcoal produced from Eucalyptus grandis and Miombo native species, in order to support new energy plantation projects, as well as adequate interventions toward the improvement of residential cooking and heating appliances in Mozambique. All charcoals were produced on a laboratory scale at a final temperature of 450 °C. Charcoal samples were collected, and their proximate chemical composition, heat value, combustion parameters, and indexes obtained by thermogravimetric analysis were evaluated. The charcoal from Eucalyptus grandis presented lower ash content (0.49%) and fuel ratio (2.81), higher content of volatile materials (26.14%), and heat value (31.15 MJ kg−1) as compared to charcoal from Miombo species. However, Miombo species presented a higher combustion performance, especially Uapaca kirkiana, which presented higher combustibility (1.37 × 104% min−1/°C2) and ignition (13.13 × 103% min−3) indexes. Eucalyptus grandis is a fast-growing species, and its charcoal presented suitable chemical properties and combustibility for domestic use; therefore, its use as an alternative to Miombo species is recommended. [ABSTRACT FROM AUTHOR]

The depletion of fossil energy reserves and the emission of fossil energy which is not environmentally friendly causes the need to use renewable energy as an alternative. Biopellet is a biomass-based renewable energy in Indonesia. Bio-pellets are produced from a large biomass base. Thus, bio-pellets have the potential and promise to continue to be used as fuel by humans. The literature review covers the characteristics of rice husk bio-pellets and the application of bio-pellets as fuel with the addition of Fatty Acid Methyl Ester (FAME) as an additive to rice husk bio-pellets. Bio-pellets can be made by mixing biomass with an adhesive with a concentration of 15% (w/w), then stirring until homogeneous and put into a pellet mill to be printed. The pellets were dried in the oven for 30 minutes. Characteristically, bio-pellets meet SNI 8021-2014 for the parameters of ash content, fixed carbon content, calorific value, moisture content, and volatile matter content. Applying bio-pellets as a furnace also shows good performance of heat, efficiency, and emission parameters. In conclusion, biopellet is a biomass-based renewable energy fuel with current and promising potential. [ABSTRACT FROM AUTHOR]

This work aimed to observe the influence of calorific value and proximate properties in the fabrication of rice husk (RH) and coffee shell (CS) briquettes composite. Rice and coffee husks contain cellulose, hemicellulose, and lignin. These contents are necessary for the adhesive to bind the briquette (amylose and amylopectin). The raw materials were carbonized at 400 °C for 60 minutes. Variations of sieving size (60, 80, and 100 mesh) and the composition ratio of raw material CS:RH were reviewed to study their effect. Tests of density, moisture content, volatile matter content, ash content, fixed carbon content, shatter index, combustion rate, and calorific value were carried out to determine the optimum composition. The results were obtained with the best quality at a particle size of 60 mesh with the highest calorific value of 17.422 MJ/kg. It showed that the briquettes have good quality and are comparable with the standard briquette. [ABSTRACT FROM AUTHOR]

Ferrosilicon production is based on the carbothermal reduction of silica and iron oxide in submerged electric arc furnaces. The reducing process of iron oxide and silicon oxide is carried out by the carbon contained in carbon materials such as coal, charcoal, semi-coke, and all types of coke. Based on its inherent and functional characteristics, the kind of carbon material can be effective in the ferrosilicon production process and furnace energy consumption. Therefore, in this work, which was performed by Iran Ferrosilice company, in a long period of 5 years, the effects of seven combinations of different carbon materials on the electrical and metallurgical performance of the process were investigated. The results showed that the minimum value of energy coefficient per ton (8.46 MWh/ton) was obtained using combination 5 (consisting of 55% coal, 30% semi-coke, 5% charcoal, and wood chips). The use of wood chips reduced the energy consumption by 3.03 MWh/ton. The composition consisting of 50% coal, 35% semi-coke, 15% charcoal, and wood chips had the highest Si% of 73.64% and the lowest Al% of 1.54%. Finally, by evaluating all the results, especially the reduction of energy consumption and recovery of Si, compound 5 was introduced as the optimal compound in the ferrosilicon production process.

One viable option for meeting global energy demand is the creation of biofuels from plant species that demonstrate high biomass productivity and good energy characteristics. In this study, growth was evaluated using plant height (PH), the production of green (GB) and dry biomass (DB), and the energy quality of leaves, pods, and stems, considering apical and basal sections of maralfalfa plants at 28, 60, 90, and 140 days after applying a uniformity cut (AUC). The variables were analyzed with correlation tests and variance analyses (ANOVA) using a factorial array design; in addition, Tukey tests were performed. A steady increase in PH (72 to 239 cm) was found. The highest yield of stems was at 90 AUC (41,362 kg/ha) for GB and 140 days AUC (6331 kg/ha) for DB, and a high correlation was observed between PH and stem biomass production for both the GB (r = 0.91) and DB (r = 0.93). There was a strong correlation between higher heating value and DB from the apical stratum (r = 0.99) and the basal stratum (r = 0.97). Maralfalfa shows high biomass productivity and high energy production in short growth periods. [ABSTRACT FROM AUTHOR]

This study was designed to determine charcoal consumers' preference of tree species and the calorific value of the charcoal produced in semi-arid region such as Goro District in South-East Ethiopia. A total of 134 households were selected proportionally using systematic sampling techniques. Samples were selected from five tree species such as Acacia nilotica, Acacia etbaica, Pappea capensis, Acacia seyal, and Acokanthera schimperi that processed into charcoal. The calorific value and fixed carbon of the charcoal specimens were computed through experimental determination of their moisture, volatile matter, and ash content, and analyzed using inferential statistics. The results shows that consumers are purchase charcoal made from Acacia nilotica, Acacia etbaica, Acacia seyal, Pappea capensis, and Acokanthera chimperi in a decreasing order of their preference. Laboratory analysis indicated the following result: moisture (4.220±0.84 - 9.8% ± 0.2), ash (3.2 ± 0.08 - 6.0 ± 0.05%), volatile matter (28.9 ± 0.66 - 32.56% ± 0.83), and fixed carbon content (51.6 ± 0.67-63.7 ± 0.21%). The calorific value of Acacia nilotica, Acacia etbaica, Pappea capensis, Acacia seyal, and Acokanthera schimperi were found to be 31.5 ± 0.26, 30.6 ± 0.96, 29.9 ± 0.58, 29.6 ± 0.28, and 28.6 ± 0.05 KJ/g, respectively, and there is statistically significant difference (Pvalue< 0.05). It is further concluded that except some variation community preference on tree species for charcoal production match with experimental results. In areas where fuel woods are available with proper management and afforestation, it is recommended to use high calorific value charcoal with modern stoves. [ABSTRACT FROM AUTHOR]

Briquetting is one way of making efficient use of existing resources. It involves collecting combustible waste materials due to lack of density, and compressing them into solid fuels of convenient shape that can be burnt like wood or charcoal". "Biomass briquette is one of the proven ways of generating energy from waste". "The excessive use of fossil fuels, wood fuels and natural gas has led to serious environmental issues and deforestation". "This work focused on estimating the heating values of sawdust briquettes to ascertain its suitability for domestic use and small-scale industrial cottage application". The calorific value of the briquettes was determined using a bomb calorimeter. "The following heating values of sawdust briquettes were obtained: average percentage moisture content 5.04%, average percentage volatile matter 10.80%, average percentage ash content 3.85%, average percentage fixed carbon 80.95% and average percentage calorific value 26918.02KCal/Kg. These results indicate that the briquettes made from sawdust have high heating values enough for domestic use and small-scale industrial cottage applications [ABSTRACT FROM AUTHOR]

A comprehensive study was conducted on the characteristics of oxygen-controlled carbonization process of sewage sludge (SS) using thermogravimetric analysis and lab-scale carbonization experiment. Reaction temperature of SS carbonization was varied between 250 and 650 °C in carrier gas with different O2 contents. The thermal process of SS in low oxygen could be divided into three stages: dehydration (below 160 °C), devolatilization (160–380 °C), stubborn volatile decomposition and fixed carbon combustion (380–600 °C). Based on Kissinger–Akahira–Sunose (KAS) and Flynn–Wall–Ozawa (FWO) methods, the reaction activation energy (E) of SS carbonization process in 10% O2 was the lowest, with values of 98.50 kJ mol−1 (KAS) and 103.49 kJ mol−1 (FWO). The properties of the obtained char, tar, and gas products were analyzed by FTIR and GC–MS. With the increase of carbonization temperature, char yield decreased and gas yield increased. The highest yield of tar was 27.76% (N2) and 27.04% (10% O2) at 450 °C. Low-oxygen atmosphere at the same temperature did not change the yield of char but increased the fixed carbon content and its aromaticity. Oxygen would participate in secondary cracking in tar and promote gas generation above 350 °C. It was found that the presence of oxygen not only increased the concentration of H2, CO, and CH4 in gas product, but also improved the quality of tar in terms of high aromatic content and low nitrogen-containing compounds. [ABSTRACT FROM AUTHOR]

This study has been carried out on the upgradation of low-grade coals of Akkakhel, Akhorwal and Shekhan areas in western Khyber Pakhtunkhwa, Pakistan. The coals of these areas, because of high ash and sulfur contents and low Gross Calorific Values (GCV) are being mined on small scale for domestic purposes only. In this work, attempts have been made to reduce sulfur and ash contents from high ash and sulfur coal which will ultimately increase the fixed carbon and GCV of the studied coal from aforementioned coal mines by froth flotation technique. During this technique, the use of kerosene as a collector and pine oil as a frother at various particle sizes (i.e., -80, -100 and -140 mesh) has decreased ash and sulfur contents in the studied coal samples. The optimum process parameters were established at -140 mesh particle size with 20 % solids in floation pulp at pH 9. Under these conditions ash was reduced from 40.6 to 13.8% (66 % reduction) and sulfur from 3.97 to 1.51% (62 % reduction) while the GCV was enhanced from 7070 to 7963 kcal/kg in the coal samples of Akkakhel area. In the coal samples of Akhorwal area, ash was reduced from 35 to 18.16% (48.11% reduction) and sulfur from 6.31 to 3.51% (44.37% reduction) while the GCV was enhanced from 5500 to 6108 kcal/ kg. Similarly, in the coal samples of Shekhan area, ash was reduced from 41.6 to 20.1% (51.68% reduction) and sulfur from 3.1 to 1.5% (51.61% reduction) while the GCV was enhanced from 3995 to 4941 kcal/ kg. The final upgraded product was found suitable for use in power plants, boilers, and cement industries etc. [ABSTRACT FROM AUTHOR]

Biomass waste contributes 14% of the total global energy. And 15–20% of the coal-fine waste from coal mines are deposited in the rivers, ponds, etc., unused, which leads to resource wastage and environmental pollution. The present study aims utilizing biomass and coal-fine waste for producing biomass-coal briquettes without using a binding material. Three different average sizes 50, 134.3, and 199.7 μm of biomass mixture (bagasse, groundnut shell, and woodchips) and coal-fines were used to make different ratios of biomass and coal mixture briquettes. Then, it is subjected to proximate, scanning electron microscope/elemental (SEM/EDX) and thermo-gravimetric analysis (TGA) to understand its property. Proximate analysis results revealed that the biomass waste has the low ash, sensible fixed carbon, and high volatile matter content. A briquette of biomass: coal = 7:1 ratio 50-μm particle size case was chosen for SEM/EDX and TGA analysis since it holds reasonable fixed carbon value comparatively. SEM analysis revealed irregular surfaces, cracks, cavities and longitudinal cracks, veins distribution all around, ups and shallows on the surface and it is the most favorable condition for fuel combustion since oxidant reaches the core of the fuel with less resistant. TGA reconfirms the spontaneous burning characteristics of the entire volatiles and fixed carbon. EDX analysis shows that the carbon and potassium are the two major elements present in the tested briquettes. [ABSTRACT FROM AUTHOR]

The increasing demand for sustainable energy solutions has driven interest in the utilization of agricultural residues, such as coconut shells, for bio-briquette production. This study investigates the impact of binder types (cassava and corn) and concentrations (5 wt%, 10 wt%, 15 wt%) on the properties of bio-briquettes made from dried coconut shells with two particle sizes (40 mesh and 60 mesh). The experimental evaluation focuses on several performance indicators, including density, shatter index, percentage moisture content (PMC), percentage volatile matter (PVM), percentage ash content (PAC), percentage fixed carbon (PFC), higher heating value (HHV), ignition time, burning time, and boiling time. The results indicate that briquettes with 10 % fine charcoal cassava binder achieved the highest density of 0.764 g/cm³ due to improved compaction. Briquettes with 15 % coarse charcoal corn binder demonstrated the highest shatter resistance at 96.99 %, reflecting their superior structural integrity. The highest PMC and PVM values were observed in briquettes with 15 % coarse charcoal cassava binder, at 8.13 % and 31.25 %, respectively. Conversely, the highest PAC was 16.34 % for 5 % coarse charcoal cassava binder. Briquettes with 10 % fine charcoal corn binder exhibited the highest PFC of 70.79 % and HHV of 31.51 MJ/kg. Boiling times ranged from 15 min 53 s to 36 min 35 s, with the shortest boiling time for briquettes with 10 % fine charcoal corn binder. The findings highlight the superior mechanical properties and energy performance of bio-briquettes with specific binder concentrations and particle sizes. This study demonstrates the potential of coconut shell bio-briquettes as a viable and sustainable energy source, offering economic and environmental benefits through the effective utilization of agricultural waste and reduction of carbon emissions., Competing Interests: The authors declare no conflict of interest, (© 2024 The Authors.)

One viable option for meeting global energy demand is the creation of biofuels from plant species that demonstrate high biomass productivity and good energy characteristics. In this study, growth was evaluated using plant height (PH), the production of green (GB) and dry biomass (DB), and the energy quality of leaves, pods, and stems, considering apical and basal sections of maralfalfa plants at 28, 60, 90, and 140 days after applying a uniformity cut (AUC). The variables were analyzed with correlation tests and variance analyses (ANOVA) using a factorial array design; in addition, Tukey tests were performed. A steady increase in PH (72 to 239 cm) was found. The highest yield of stems was at 90 AUC (41,362 kg/ha) for GB and 140 days AUC (6331 kg/ha) for DB, and a high correlation was observed between PH and stem biomass production for both the GB (r = 0.91) and DB (r = 0.93). There was a strong correlation between higher heating value and DB from the apical stratum (r = 0.99) and the basal stratum (r = 0.97). Maralfalfa shows high biomass productivity and high energy production in short growth periods.

A correlation study of gross calorific value of coal with parameters of proximate analysis (the content of ash, moisture, volatile matter and fixed carbon) was studied on more than 200 samples of coal from different mining areas across India. Gross calorific value is increased with the decrease of the content of ash, moisture respectively, and gross calorific value is also increased with the increase in the content of volatile matter and fixed carbon respectively. The relevant experimental data and graphs are very useful for industries to estimate the quality of coal. [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.)

Response surface methodology was employed to optimize pyrolysis conditions for production of char with maximum yield, fixed carbon content, and with minimum ash content from Uganda's New Rice for Africa (NERICA) 1 rice husk variety. The aim was to obtain rice husk char with more suitable properties as an activated carbon precursor. Mathematical models were developed to explain the relationships between the experimental responses and the pyrolysis parameters of temperature (400–600 °C), heating rate (10–25 °C min−1), and heating period (60–120 min). The optimized rice husk char was further characterized for elemental and proximate compositions, thermal behavior, specific surface area, as well as surface functional groups. Results from the analysis of variance (ANOVA) revealed that the quadratic model best fits each of the responses. Pyrolysis temperature had the greatest influence on each of the responses, followed by heating period, and lastly heating rate. Optimum pyrolysis conditions were found to be temperature (406 °C), heating rate (10 °C min−1), and heating period (60 min), resulting in char yield, fixed carbon, and ash contents of 35.26, 55.39, and 35.01% dry basis, respectively. Compared to raw rice husk, the resulting rice husk char was found more suited as activated carbon precursor, due to its enriched carbon content (60.35%) and specific surface area (123.9 m2 g−1). Thermogravimetric analysis of the rice husk char revealed that thermal activation temperatures higher than 400 °C may be required to considerably devolatilize the char, forming a more porous activated carbon. [ABSTRACT FROM AUTHOR]

The charcoals of Amapá, a Brazilian state located in the Amazonia forest, have been produced from wastes of high-quality native and exotic wood species. However, there is no control to avoid mixing raw materials with different potentials for bioenergy. This work aimed to compare the quality of two brands of Amapá charcoals for domestic use, besides to analyze the variability of properties within and among packages. Charcoals of brands A and B were produced from harvesting wastes of Acacia mangium wood and sawing wastes of mixed native wood species, respectively. Five packages of each brand were acquired, from which thirteen samples were randomly selected for physical and chemical analyses. The higher heating value was estimated from the chemical composition. The brands were compared by analysis of variance or Wilcoxon–Mann–Whitney test. The variability within and between packages was investigated through box plots. The Amapá charcoals showed moisture content (≈ 7.3%) somewhat above the stipulated (5%) by the Brazilian standardization for domestic use. The proper quality of the charcoals was attested by high apparent density (≈ 0.568 g/cm3), high fixed carbon (≈ 87.2%), low volatile matter (≈ 11.7%), low ash content (≈ 1.0%) and high higher heating value (≈ 32,925.40 kJ/kg). The charcoal of the brand B showed better quality considering significant higher average apparent density, no outlier of ash content above the maximum ideal value and overall lower variability within and among packages of the properties. The apparent density greatly varied among packages, while a greater variation within packages was observed for the other properties. [ABSTRACT FROM AUTHOR]

In order to understand the geological characteristics and ore-controlling factors of graphite ore more accurately, in this study, the geological characteristics, genetic analysis, ore-controlling factors, and prospecting direction of Yandilatu and Kujinggou graphite deposits in southern Inner Mongolia are studied by means of field survey, instrument analysis, and chemical detection. The results show that the shape of Yandilatu graphite deposit is near the level, the burial depth is 46–62 m, the thickness of ore body is 16.32–116.31 m, the fixed carbon content is 2.48–9.50%, and the average thickness of Kujinggou graphite deposit is 149 m. Four layers of ore bodies with fixed carbon content of 2.43–19.53% are found, which belong to large crystalline graphite. In summary, the prospecting potential of graphite deposits in this area is great. Most of them are concealed ore bodies. The combination of geophysical prospecting and drilling has become a fast and effective means of prospecting in this area. The top limestone and the roof kaolin of graphite ore bodies are important indirect indicators of prospecting for graphite deposits in this area. Therefore, this study is of great significance for the rapid and accurate exploration of graphite ore and the maximum use of graphite ore in China. [ABSTRACT FROM AUTHOR]

Previous research has found that the fixed carbon in blast furnace dust (BFD) could be used as the reductant of co-reduction roasting of the iron oxides in seaside titanomagnetite and BFD to replace coals. This research studied the influence mechanism of the fixed carbon and ash in BFD on co-reduction. Results showed that both fixed carbon and ash in BFD promoted the reduction of iron, while ash had adverse effect on separation of titanium and iron. The main mechanism was as follows: The ash in BFD accelerated melting. In addition, the iron oxide in the ash of BFD could be reduced to metallic iron cores more easily in the initial stage, providing the site of inhomogeneous core and promoting the aggregation and growth of metallic iron. Furthermore, the fixed carbon mainly reacted with iron ore by solid-solid reaction, leading to a rapid reduction rate and a high utilization rate of fixed carbon. [ABSTRACT FROM AUTHOR]

The aim of this study was to determine selected energy parameters, leachability of heavy metals and phytotoxicity of biomass ash for different types of plant biomass (wheat straw, miscanthus straw, bark and sawdust) and poultry manure, as well as biochars produced from them. Based on data from proximate and ultimate analysis of the investigated materials, fuel value index (FVI) was calculated to determine their suitability for energy production. The ashes were analyzed for both chemical composition and leaching behavior. The phytotoxicity test of aqueous ash extracts was performed for Lepidium sativum L. It was found that the calorific value of biochars was higher on average by 36% than the value determined for feedstocks used in the pyrolysis process. The pyrolysis of organic materials resulted in the reduction of the volatile matter content. The gross calorific value was determined in biochars formed from miscanthus straw and sawdust which were 26.6 and 23.4 MJ kg−1, respectively. Leachability of heavy metals of biomass ash was highly diverse and depended on the analyzed element and the material type. The phytotoxicity analysis showed that, in general, each of the ash extracts tested had a positive effect on the growth of Lepidium sativum L. compared to the control. The use of ash, fertilizer, or sorbents can be an interesting alternative for materials with high ash content. In all these cases, biochars seem to be very attractive materials that can be used not only in energy production. Given the high carbon content of biochar obtained in the pyrolysis process, it has a high-energy potential and can be used as a biofuel. [ABSTRACT FROM AUTHOR]

The objective of this study was to characterize the properties of charcoal produced in industrial rectangular furnaces, using principal components analysis. For this, three industrial stocks of charcoal were sampled from Furnace I and II, with volumetric capacity of 500 and 180m3 of wood, respectively. The average particle size, fines content, bulk density and proximate composition were determined. Descriptive analysis and principal component analysis were carried out to evaluate the relationships between charcoal properties. In general, for both furnaces, it was found that the average particle size showed a negative relationship with fines content as the bulk density had a positive relationship with the content of fines. However, the relationship between the fixed carbon and ash content for Furnace I was direct, and for Furnace II was inverse. The charcoal properties of the rectangular furnaces, in general, present a medium asymmetry. The charcoal has a high variability in its properties, however, it is possible, by operating adjustments to improve the quality of coal to the consumer. [ABSTRACT FROM AUTHOR]

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In order to develop economically and environmentally sustainable productive activities, the effect of three agroforestry systems (SAF) of the cocoa crop was evaluated. The variable responses were the capture and storage of carbon, in the shrub, tree and soil biomass. The SAF of cocoa were from different physiographic units with ages, under 8 years, between 8 to 16 years and over 16 years. The statistical design was used completely at random, the allometric method; the organic carbon estimate was determined by the Walkley and Black method. The highest total carbon storage was reached by the SAF over 16 years with 344.24 t C / ha, the SAF between 8 and 16 years with 178.61 t C / ha, and the SAF under 8 years with 154.91 t C / ha. higher organic carbon was found in the soil in the SAF with cacao less than 8 years old, with 66.16 t C / ha between the soil layer of 0 to 10 cm. The economic analysis VAN, TIR and RB / C indicated that the best result was the SAF under 8 years with S /. 2627.66; 23.85%; and 1.40 respectively. The SAF over 16 years, obtained the S/. 1331.38, 21.64%, 1.21%, providing more environmental services. [ABSTRACT FROM AUTHOR]

This work illustrates the proximate analysis on three types of coal samples obtained from Khushab mines in Pakistan. Analysis of the coal matrix was carried out to determine volatile matter, ash contents, moisture, fixed carbon contents, calorific values, and sulfur contents as per standards of American Society for Testing and Materials (ASTM). The results of proximate analysis show 30.46% fixed carbon content, 28.08% ash content, 6.96% total moisture content, and 34.5% volatile matter within sample A, whereas 40.56% volatile matter, 8.03% moisture content, 8.32% ash and 30.46% fixed carbon content was found in sample B. Sample C contained 15.44% volatile matter, 9.16% moisture content, 40.64% ash content, and 37.5% fixed carbon content, respectively. Sample B has higher calorific value and sulphur contents in comparison to A and C. These coal samples are of good quality from an industrial prospective, but they need to be desulphurized prior to industrial use for the sake of the environment. [ABSTRACT FROM AUTHOR]

This study was carried out to determine the physical and combustion properties of briquettes produced from the leaves of Tectona grandis and mixture of Tectona grandis and Daniella oliveri sawdust. The different samples were made in single and binary combination in a ratio of 100: 0 and 50:50 respectively, using cassava starch as binder. The briquettes were produced mechanically using a hydraulic machine at pressure of KN/m2.The data collected was analyzed using a 2×3 factorial CRD. The compressed densities were determined at 0 minutes and relaxed densities at 30mins, 24hrs, and 7days; Tectona grandis had a higher relaxed density of 0.57g/cm³ in 7days of drying. The briquettes produced from binary combination of Tectona grandis with Daniella oliveri had a higher shatter resistance of 99.50% and weight loss 0.49%. The effect of combustion properties on briquette type was significant except for percentage of moisture content and fixed carbon. Briquettes produced at binary combination of Tectona grandis with Daniella oliveri had a lower moisture content, ash content, fixed carbon content and volatile matter of 7.17%, 18.66%, 9.2% and 72.2% respectively. The heating value of Tectona grandis with Daniella oliveri briquettes at 11297MJ/kg was higher than Tectona grandis briquettes with 10721MJ/kg. The effect of particle sizes on combustion properties was significant except on percentage moisture content and fixed carbon, briquettes produced at particle size of 1.70mm recorded the lowest percentage ash content of 9.5%, but highest heating value of 11055MJ/kg. Briquettes produced from leaves of Tectona grandis and sawdust of Daniella oliveri are good alternative briquette biomass materials for domestic cooking by low income earners. [ABSTRACT FROM AUTHOR]