ICOPE-15-1024 Estimation of Energy Density and Energy Yield of Torrefied Biomass with Colorimetric Values

The increased food intake of rats exposed to cold is the result of increased intake due to cold (cold-specific compartment; A) and decreased intake due to simultaneously decreased body weight (weight-specific compartment; B). The two compartments are evaluated at 5, 13, and 17 degrees C. B is evaluated as the food intake of theoretical, isogravimetric control (identical to cold-exposed rats with respect to body weight and rate of change of body weight and identical to nonexposed rats in all other respects) that takes into account both the change in energy expenditure due to decreased body weight and the energy yield from tissue catabolism represented by change of body weight. A is the observed food intake minus B. A theoretical heat-flow model, in which expected changes in heat flow during cold exposure drive food intake to maintain or restore preexposure body weight status, corroborated the partition derived from experimental data. However, both the experimental results and the heat-flow model imply that the energy density of body weight change is negatively correlated with rate of body weight change. The energy density of weight change is high with high rates of weight loss and low with high rats of weight gain.

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Improvement of energy density and energy yield of oil palm biomass by torrefaction in combustion gas

IOP Conference Series Materials Science and Engineering ◽

10.1088/1757-899x/458/1/012061 ◽

2018 ◽

Vol 458 ◽

pp. 012061 ◽

Cited By ~ 1

Author(s):

Y Uemura ◽

V Sellappah ◽

T H Trinh ◽

M Komiyama ◽

S Hassan ◽

...

Keyword(s):

Energy Density ◽

Oil Palm ◽

Energy Yield ◽

Combustion Gas ◽

Oil Palm Biomass

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Effects of Reactor Design on the Torrefaction of Biomass

Journal of Energy Resources Technology ◽

10.1115/1.4007484 ◽

2012 ◽

Vol 134 (4) ◽

Cited By ~ 35

Author(s):

Alok Dhungana ◽

Prabir Basu ◽

Animesh Dutta

Keyword(s):

Energy Density ◽

Fluidized Beds ◽

Process Conditions ◽

Convective Heating ◽

Energy Yield ◽

Mass Yield ◽

Rotating Drum ◽

Volumetric Heating ◽

Direct Heating ◽

Common Basis

Torrefied biomass is a green alternative to coal, and thus the interest in the torrefaction process is rising fast. Different manufacturers are offering different patented designs of torrefier with data on varying operating and process conditions each claiming their superiority over others. The choice of torrefaction technology has become exceptionally difficult because of a near absence of a comparative assessment of different types of reactors on a common base. This work attempts to fill this important knowledge gap in torrefaction technology by reviewing available types of reactors, and comparing their torrefaction performance common basis and examining the commercial implication of reactor choice. After reviewing available patent and technologies offered, torrefiers are classified broadly under two generic groups: indirectly heated and directly heated. Four generic types of reactors, convective heating, fluidized bed, rotating drum and microwave reactor were studied in this research. Convective and fluidized beds have direct heating, rotating reactors has indirect heating while microwave involves a volumetric heating (a subgroup of direct heating) mechanism. A standard sample of biomass (25 mm diameter × 64 mm long poplar wood) was torrefied in each of these types of reactors under identical conditions. The mass yield, energy density and energy yield of the wood after torrefaction were measured and compared. Rotating drum achieved lowest mass yield but highest energy density. The difference between two direct heating, convective heating and fluidized beds was small. Microwave provided only localized torrefaction in this series of tests. Indirectly heated reactors might be suitable for a plant near the biomass source while directly heated plant would give better value at the user end.

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Modeling Woody Biomass Torrefaction Process

Volume 6A: Energy ◽

10.1115/imece2018-87974 ◽

2018 ◽

Author(s):

Mahmudul Hasan ◽

Yousef Haseli

Keyword(s):

Specific Heat ◽

Formation Enthalpy ◽

Energy Yield ◽

Sensible Heat ◽

Total Enthalpy ◽

Elemental Compositions ◽

Combustion Properties ◽

Torrefied Biomass ◽

Mass Fractions ◽

Yield Formation

Torrefaction is a thermal pretreatment process which usually takes place at temperatures between 200–300°C. Torrefied biomass has been proven in numerous studies to have superior combustion properties compared to raw biomass. The objective of this study is to develop a model to estimate solid energy yield, elemental compositions and enthalpy of solid and volatile yield. Formation enthalpy of raw and torrefied biomass is calculated using the correlations developed for elemental compositions and HHV of torrefied biomass. Solid yield is determined by anhydrous weight loss model for torrefied wood. Specific heat correlations for raw biomass and char are used to calculate the sensible heat required for torrefaction process. Sensible heat and formation enthalpy give the total enthalpy for raw and torrefied biomass. During torrefaction, a mixture of volatile compositions is released. Experimental mass fractions of the volatiles components are taken from published literature, which allowed us to determine the enthalpy of formation and specific heat of the volatiles. Finally, the model results associated with the torrefaction process are compared with experimental data.

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Traditional Farming

Energy and Civilization ◽

10.7551/mitpress/9780262035774.003.0003 ◽

2017 ◽

Author(s):

Vaclav Smil

Keyword(s):

Energy Density ◽

Traditional Agriculture ◽

Energy Yield ◽

Nutritional Content ◽

Farming Practices ◽

Land Productivity ◽

Traditional Farming ◽

Digestible Energy ◽

Agronomic Practices ◽

Vegetarian Diets

This chapter discusses the use of energy in traditional farming. The evolution of agriculture appears to be a continuing effort to increase land productivity (to increase digestible energy yield) in order to accommodate larger populations. Owing to the overwhelmingly vegetarian diets of all traditional peasant societies, it is important to focus on the output of digestible energy produced in staple crops in general and grains in particular. The chapter first provides an overview of the link between food energy and the evolution of peasant societies before considering the commonalities and peculiarities of tools and machines used in agronomic practices. It then examines the dominance of grains in traditional agriculture, with particular emphasis on their energy density and nutritional content. It also analyzes routes to gradual intensification of agriculture, along with the persistence and innovation in traditional farming practices. Finally, it assesses the limits and achievements of traditional agriculture.

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Bioenergy yield of Eucalyptus urophylla clones and its relationship with the mean annual increment of wood volume

Canadian Journal of Forest Research ◽

10.1139/cjfr-2020-0407 ◽

2021 ◽

Author(s):

Bruna Isabele Pinheiro da Silva ◽

Alyne Chaveiro Santos ◽

Macksuel Fernandes da Silva ◽

Mariana Dianese Alves de Moraes ◽

Carlos Roberto Sette Jr

Keyword(s):

Energy Density ◽

Basic Density ◽

Dry Mass ◽

Energy Yield ◽

Eucalyptus Urophylla ◽

Annual Increment ◽

Wood Volume ◽

Wood Basic Density ◽

The Difference ◽

Mean Annual Increment

This study aimed to evaluate the energy yield and wood characteristics of Eucalyptus urophylla clones with different mean annual increment of wood volume (MAI). The clones presented MAIs of 39.2, 54.1 and 70.0 m3 ha-1 yr-1 in the field experiment at six years after planting when the trees were cut down to evaluate the wood basic density and higher heating values. The energy density, dry mass and energy yield were estimated. The MAI of E. urophylla clones influenced the wood basic density, dry mass, and energy yield, but did not influence the higher heating value and energy density. Clone 3 had the highest MAI, and also had higher energy yield and dry mass, but lower wood basic density. The difference between the most and the least productive clones was 242,648 MJ ha-1 yr-1. The results reinforce the importance of evaluating the wood quantity production (MAI) to select Eucalyptus clones for energy purposes.

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Fuel Properties of Torrefied Biomass from Sapindus Pericarp Extraction Residue under a Wide Range of Pyrolysis Conditions

Energies ◽

10.3390/en14217122 ◽

2021 ◽

Vol 14 (21) ◽

pp. 7122

Author(s):

Wen-Tien Tsai ◽

Tasi-Jung Jiang ◽

Yu-Quan Lin ◽

Xiang Zhang ◽

Kung-Sheng Yeh ◽

...

Keyword(s):

Calorific Value ◽

Fuel Properties ◽

Energy Yield ◽

Residence Times ◽

Significant Weight Loss ◽

X Ray ◽

Wide Range ◽

Torrefied Biomass ◽

Increasing Trend ◽

Van Krevelen Diagram

In this work, a novel biomass, the extraction residue of Sapindus pericarp (SP), was torrefied by using an electronic oven under a wide range of temperature (i.e., 200–320 °C) and residence times (i.e., 0–60 min). From the results of the thermogravimetric analysis (TGA) of SP, a significant weight loss was observed in the temperature range of 200–400 °C, which can be divided into the decompositions of hemicellulose (major)/lignin (minor) (200–320 °C) and cellulose (major)/lignin (minor) (320–400 °C). Based on the fuel properties of the feedstock SP and SP-torrefied products, the optimal torrefaction conditions can be found at around 280 °C for holding 30 min, showing that the calorific value, enhancement factor and energy yield of the torrefied biomass were enhanced to be 28.60 MJ/kg, 1.36 and 82.04 wt%, respectively. Consistently, the values of the calorific value, carbon content and molar carbon/hydrogen (C/H) ratio indicated an increasing trend at higher torrefaction temperatures and/or longer residence times. The findings showed that some SP-torrefied solids can be grouped into the characteristics of a lignite-like biomass by a van Krevelen diagram for all the SP-torrefied products. However, the SP-torrefied fuels would be particularly susceptible to the problems of slagging and fouling because of the relatively high contents of potassium (K) and calcium (Ca) based on the analytical results of the energy dispersive X-ray spectroscopy (EDS).

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Upgrading Refuse-Derived Fuel Properties From Reclaimed Landfill Using Torrefaction

Journal of Energy Resources Technology ◽

10.1115/1.4047979 ◽

2020 ◽

Vol 143 (2) ◽

Author(s):

S. Kerdsuwan ◽

K. Laohalidanond ◽

K. Gupta Ashwani

Keyword(s):

Energy Density ◽

Density Ratio ◽

Fuel Properties ◽

Energy Yield ◽

Hydrophobic Property ◽

Heating Value ◽

Refuse Derived Fuel ◽

Attractive Option ◽

Fuel Upgrading ◽

Direct Use

Abstract Landfill resource reclamation or landfill mining offers an attractive option to harvest the primary materials remaining behind in landfills or open dump sites. After reclamation, the major fractions left after removing soil-like material are paper and plastic fractions, which can be used transformed to refuse-derived fuel (RDF) as a fuel. However, the variation of constituents in RDF causes to low-quality fuel derived from the reclaimed landfill. The torrefaction process is proposed here to upgrade the fuel properties in terms of heating value, energy density ratio, and hydrophobicity. A torrefaction oven was used to torrefy RDF from reclaimed landfill at a controlled temperature of 250, 300, and 300 °C and a residence time of approximately 30 min in an inert environment using Nitrogen gas. The experiment results showed an optimum torrefaction temperature of 250 °C, which resulted in the improved heating value of RDF by up to 14.12%, an increased energy yield of 107.78%, and an energy density ratio of 1.14. These results demonstrated greater energy yield from the torrefied RDF compared with raw RDF. The hydrophobic property of torrefied RDF was also improved with the torrefaction process due to low water adsorption capability of torrefied RDF that was evaluated to be only one-half of that of raw RDF. The fuel upgrading of RDF from reclaimed landfill achieved via the torrefaction process improved the fuel properties that offers its direct use or, in conjunction with other coal fuels, for power generation.

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Optimizing genotype-environment-management interactions to ensure silage maize production in the Chinese Maize Belt

Climate Research ◽

10.3354/cr01599 ◽

2020 ◽

Vol 80 (2) ◽

pp. 133-146

Author(s):

L Zhang ◽

Z Zhang ◽

J Cao ◽

Y Luo ◽

Z Li

Keyword(s):

Field Experiments ◽

Weather Conditions ◽

Growth Cycle ◽

High Energy ◽

Risk Level ◽

Energy Yield ◽

Maize Production ◽

Early Date ◽

Environment Management ◽

Silage Maize

Grain maize production exceeds the demand for grain maize in China. Methods for harvesting good-quality silage maize urgently need a theoretical basis and reference data in order to ensure its benefits to farmers. However, research on silage maize is limited, and very few studies have focused on its energetic value and quality. Here, we calibrated the CERES-Maize model for 24 cultivars with 93 field experiments and then performed a long-term (1980-2017) simulation to optimize genotype-environment-management (G-E-M) interactions in the 4 main agroecological zones across China. We found that CERES-Maize could reproduce the growth and development of maize well under various management and weather conditions with a phenology bias of <5 d and biomass relative root mean square error values of <5%. The simulated results showed that sowing long-growth-cycle cultivars approximately 10 d in advance could yield good-quality silage. The optimal sowing dates (from late May to July) and harvest dates (from early October to mid-November) gradually became later from north to south. A high-energy yield was expected when sowing at an early date and/or with late-maturing cultivars. We found that Northeast China and the North China Plain were potential silage maize growing areas, although these areas experienced a medium or even high frost risk. Southwestern maize experienced a low risk level, but the low soil fertility limited the attainable yield. The results of this paper provide information for designing an optimal G×E×M strategy to ensure silage maize production in the Chinese Maize Belt.

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Fine-scale taxonomic and temporal variability in the energy density of invertebrate prey of juvenile Chinook salmon Oncorhynchus tshawytscha

Marine Ecology Progress Series ◽

10.3354/meps13513 ◽

2020 ◽

Vol 655 ◽

pp. 185-198

Author(s):

J Weil ◽

WDP Duguid ◽

F Juanes

Keyword(s):

Energy Density ◽

Chinook Salmon ◽

Temporal Variability ◽

Energy Content ◽

Single Point ◽

Single Species ◽

Fine Scale ◽

Temporal Differences ◽

Juvenile Chinook Salmon ◽

Juvenile Chinook

Variation in the energy content of prey can drive the diet choice, growth and ultimate survival of consumers. In Pacific salmon species, obtaining sufficient energy for rapid growth during early marine residence is hypothesized to reduce the risk of size-selective mortality. In order to determine the energetic benefit of feeding choices for individuals, accurate estimates of energy density (ED) across prey groups are required. Frequently, a single species is assumed to be representative of a larger taxonomic group or related species. Further, single-point estimates are often assumed to be representative of a group across seasons, despite temporal variability. To test the validity of these practices, we sampled zooplankton prey of juvenile Chinook salmon to investigate fine-scale taxonomic and temporal differences in ED. Using a recently developed model to estimate the ED of organisms using percent ash-free dry weight, we compared energy content of several groups that are typically grouped together in growth studies. Decapod megalopae were more energy rich than zoeae and showed family-level variability in ED. Amphipods showed significant species-level variability in ED. Temporal differences were observed, but patterns were not consistent among groups. Bioenergetic model simulations showed that growth rate of juvenile Chinook salmon was almost identical when prey ED values were calculated on a fine scale or on a taxon-averaged coarse scale. However, single-species representative calculations of prey ED yielded highly variable output in growth depending on the representative species used. These results suggest that the latter approach may yield significantly biased results.

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