Physical, mechanical and energy characterization of wood pellets obtained from three common tropical species

Background The need for energy sources with low greenhouse gas emissions and sustainable production encourages the search for alternative biomass sources. However, the use of biomass fuels faces the problem of storage, transport and lower energy densities. Low-density values can negatively affect energy density, leading to an increase in transportation and storage costs. Use of pellets as alternative biomass source is a way to reduce the volume of biomass by densification, which improves their energy quality. They are produced by diverse biomass resources and mainly from wood materials. In all cases, it is important to evaluate the fuel characteristics, to determine their suitability on the heating system and handling properties. Methods The present study determines and compares data from proximate analysis, calorific values, physical and mechanical properties of wood pellets produced from the common tropical species Acacia wrightii, Ebenopsis ebano and Havardia pallens. Data were obtained from pellets produced from each species chips collected from an experimental plantation and analyzed through ANOVA and Kruskal–Wallis test at 0.05 significance level. Results The results of diameter, length and length/diameter ratio didn’t show statistical differences (p > 0.05) among species. Acacia wrightii showed the highest density (1.2 g/cm3). Values on weight retained and compression test showed statistical differences (p = 0.05) among species. Havardia pallens was more resistant to compression strength than A. wrightii and Ebenopsis ebano. Statistical differences (p < 0.01) were also observed for the volatile matter and calorific value. E. ebano has the lowest volatile matter (72%), highest calorific value (19.6 MJ/kg) as well as the fixed carbon (21%). Discussion The pellets of the species studied have a high energy density, which makes them suitable for both commercial and industrial heating applications.A pellet with low compression resistance tends to disintegrate easily, due to moisture adsorption. The percentages obtained for the resistance index were higher than 97.5%, showing that the pellets studied are high-quality biofuels. Proximate analysis values also indicate good combustion parameters. Pellets of Acacia wrightii and Ebenopsis ebano are the more favorable raw material sources for energy purposes because of their high density, calorific value, low ash content and they also met majority of the international quality parameters.

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Compaction as a sustainable alternative to dried sludge from poultry slaughterhouse wastewater for energy generation

Ciência Rural ◽

10.1590/0103-8478cr20200320 ◽

2021 ◽

Vol 51 (12) ◽

Author(s):

Julio Peretti da Silva ◽

Martha Andreia Brand ◽

Philipe Ricardo Casemiro Soares ◽

Matheus de Liz Salamon ◽

Taíse Mariano Rodrigues ◽

...

Keyword(s):

Energy Density ◽

Bulk Density ◽

Calorific Value ◽

Volatile Matter ◽

Proximate Analysis ◽

Charcoal Production ◽

The One ◽

Dried Sludge ◽

Pinus Spp ◽

Compressive Resistance

ABSTRACT: The generation of wastes in poultry abattoirs has increased considerably in recent years due to the growing demand for chicken meat. This fact, combined with the current need for developing new forms of renewable energy from biomass, and the lack of disposal facilities, motivated this study. We determined the technical feasibility of the barbecue charcoal production using briquettes produced with different blends containing sludge from a poultry abattoir and Pinus spp. shavings. To that end, we have mixed both residues by gradually adding 10 to 90 % of sludge in the blends, which resulted in 9 treatments containing sludge, and 1 containing only shavings. After that, we produced four briquettes of each treatment and charred them by using a heating ramp. After charring, we submitted the charcoal to the analyzes of Moisture Content (MC), Bulk Density (BD), Compressive Resistance (CR), Gross Calorific Value (GCV), and Proximate Analysis (PA). We calculated the Gravimetric Yield (GY) and the Energy Density (ED) by using the results from the other analyzes. Results showed that the CR, the GCV, the Volatile Matter (VM), and the Fixed Carbon Content (FC) of the charcoals decreased by increasing the proportion of sludge in the blends. However, the charcoals’ bulk density (BD) increased, which also increased its energy density (ED) and ash content (AC). The best blend to produce charcoal for household use was the one containing 90 % of sludge and 10 % of Pinus spp. shavings.

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Potential of Briquette Produced with Torrefied Agroforestry Biomass to Generate Energy

Forests ◽

10.3390/f11121272 ◽

2020 ◽

Vol 11 (12) ◽

pp. 1272

Author(s):

Gabriel Reis Portilho ◽

Vinicius Resende de Castro ◽

Angélica de Cássia Oliveira Carneiro ◽

José Cola Zanuncio ◽

Antonio José Vinha Zanuncio ◽

...

Keyword(s):

Energy Density ◽

Sugarcane Bagasse ◽

Compaction Pressure ◽

Calorific Value ◽

High Energy ◽

Raw Material ◽

High Energy Density ◽

Fixed Carbon ◽

Volatile Material ◽

Material Content

Agroforestry industries, such as sugar-alcohol, food, and logging, produce large quantities of waste, used to generate energy from direct burning. The application of other processes, such as torrefaction and briquetting, can increase the profits from the use of agro-industrial waste for energy generation. Briquetting is an alternative for using these wastes, allowing the compaction of the biomass, generating a biofuel with high energy density, and which is more homogeneous and easier to store and transport. The objective of this study was to evaluate the physical and chemical properties of four biomass types (wastes from sawed eucalypt and pine wood, coffee pruning wastes, and sugarcane bagasse) torrefied at 300 °C and compacted (briquetting) at pressures of 6.21, 8.27, and 10.34 MPa. The torrefaction increased the fixed carbon content, ash, and calorific value, and reduced the volatile material content and hygroscopic equilibrium moisture of the biomasses. The volatile material content was lower and the fixed carbon higher in the coffee pruning waste, the ash content higher in the sugarcane bagasse, and the calorific value higher in the pine and eucalypt wood. The briquetting and the torrefaction processes increased the biomass bulk density, and the useful calorific value, respectively, and consequently the energy density of the briquettes produced with torrefied raw material under high pressure. The mechanical properties of the briquettes produced with all materials increased with the compaction pressure. Torrefaction and briquetting increased the energy potential of the biomasses evaluated to produce energy from clean technology.

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TRENDS AND CHALLENGES OF BRAZILIAN PELLETS INDUSTRY ORIGINATED FROM AGROFORESTRY

CERNE ◽

10.1590/01047760201622032115 ◽

2016 ◽

Vol 22 (3) ◽

pp. 233-240 ◽

Cited By ~ 13

Author(s):

Dorival Pinheiro Garcia ◽

José Cláudio Caraschi ◽

Gustavo Ventorim ◽

Fabio Henrique Antunes Vieira

Keyword(s):

Energy Density ◽

Production Capacity ◽

High Energy ◽

Combustion Efficiency ◽

High Energy Density ◽

General Knowledge ◽

Wood Pellets ◽

Energy Characteristics ◽

Wood Sawdust ◽

The Subject

ABSTRACT Wood pellets are biofuels produced from agroforestry waste such as sugarcane bagasse, wood sawdust and shavings. They are compressed biofuels that have low moisture, allowing high combustion efficiency, especially because they are natural products of easily handling with high energy density. To explore pellets opportunities in Brazil (production and marketing), it is necessary to provide information about the chemical and energy characteristics, technologies, prices and prospects of this market. Thus, this article aims to organize and make this information available, enabling general knowledge on the subject and subsidize more investment in the biofuels sector; mostly by adding value to agroforestry waste, available in large volumes in this country. The results showed a young industry, with sixteen plants and production of 49.39 ktonnes of pellets in 2014, but using only 25.5% of its annual production capacity.

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Theoretical Design and Screening Potential High Energy Density Materials: Combination of 1,2,4-oxadiazole and 1,3,4-oxadiazole Rings

Физика горения и взрыва ◽

10.15372/fgv20190504 ◽

2019 ◽

Keyword(s):

Energy Density ◽

High Energy ◽

High Energy Density ◽

Theoretical Design ◽

High Energy Density Materials

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Evaluation of High Energy Density Plasma in Counter-facing Plasma Focus Device driven by Laser Triggered Pulse Power System

IEEJ Transactions on Fundamentals and Materials ◽

10.1541/ieejfms.137.564 ◽

2017 ◽

Vol 137 (10) ◽

pp. 564-569

Author(s):

Tatsuya Sodekoda ◽

Hajime Kuwabara ◽

Shotaro Kittaka ◽

Kazuhiko Horioka

Keyword(s):

Energy Density ◽

Power System ◽

Plasma Focus ◽

High Energy ◽

Pulse Power ◽

Plasma Focus Device ◽

High Energy Density ◽

Density Plasma

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A HIGH ENERGY DENSITY ZINC/OXYGEN BATTERY SYSTEM

10.2514/6.1966-2324 ◽

1966 ◽

Author(s):

S. CHODOSH ◽

E. KATSOULIS ◽

M. ROSANSKY

Keyword(s):

Energy Density ◽

High Energy ◽

High Energy Density ◽

Battery System

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Efficient Co-Harvesting of Solar Energy and Low-Grade Heat by Molecular Photoswitches for High Energy Density, Long-Term Stable Solar Thermal Battery

10.26434/chemrxiv.9730694.v1 ◽

2019 ◽

Author(s):

Zhao-Yang Zhang ◽

Tao LI

Keyword(s):

Energy Density ◽

Solar Energy ◽

High Performance ◽

High Energy ◽

Solar Thermal ◽

High Energy Density ◽

Low Grade ◽

Thermal Battery ◽

Low Grade Heat

Solar energy and ambient heat are two inexhaustible energy sources for addressing the global challenge of energy and sustainability. Solar thermal battery based on molecular switches that can store solar energy and release it as heat has recently attracted great interest, but its development is severely limited by both low energy density and short storage stability. On the other hand, the efficient recovery and upgrading of low-grade heat, especially that of the ambient heat, has been a great challenge. Here we report that solar energy and ambient heat can be simultaneously harvested and stored, which is enabled by room-temperature photochemical crystal-to-liquid transitions of small-molecule photoswitches. The two forms of energy are released together to produce high-temperature heat during the reverse photochemical phase change. This strategy, combined with molecular design, provides high energy density of 320-370 J/g and long-term storage stability (half-life of about 3 months). On this basis, we fabricate high-performance, flexible film devices of solar thermal battery, which can be readily recharged at room temperature with good cycling ability, show fast rate of heat release, and produce high-temperature heat that is >20<sup> o</sup>C higher than the ambient temperature. Our work opens up a new avenue to harvest ambient heat, and demonstrate a feasible strategy to develop high-performance solar thermal battery.

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