Analysis and Selection of the Best Model of Biomass Briquette Based on Calorific Value

The article addresses the urgent questions regarding the use of biomass as a fuel for combustion equipment of the heat output up to 25 kW. The article is based on the determined elemental analyses of six samples of fuel taken both from the wood mass and herbaceous biomass. These samples underwent the stoichiometric analysis of fuels. After the stoichiometric analysis the heat-emission characteristics were determined on two combustion equipments. The results of carried out elemental and stoichiometric analyses indicate higher values of nitrogen, sulphur and chlorine concentration in herbaceous biomass from agriculture compared to the analyzed wood mass. The selection of combustion equipment is particularly influenced by increased contents of sulphur and chlorine (corrosive behaviour). The net calorific value of the analyzed samples taken from the wood mass is higher than of samples taken from the herbaceous biomass. The net calorific value of fuels from herbaceous biomass is reduced due to a higher content of ashes in the fuel. The results of thermal-emission analyses show higher values of nitrogen oxides, sulphur and chlorine concentrations in the herbaceous biomass compared to the analyzed wood mass. The emission concentrations of carbon monoxide for wood fuels and herbaceous biomass also depend on the type of combustion equipment and setting of combustion air volume. The increased emissions of hydrogen chloride generated by various combustion equipments are primarily caused by the volume of combustion air and the amount of chlorine in the fuel itself. The higher the volume of combustion air brought into the combustion chamber is, the higher the emissions of hydrogen chloride are. Based on the analyses we can also draw a conclusion that the spaces of combustion equipment during combustion should be most burdened with the herbaceous biomass.

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Research on Calculation Method of Alternative Fuel Quantity for Natural Gas Bus

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.687-691.415 ◽

2014 ◽

Vol 687-691 ◽

pp. 415-418

Author(s):

Xiao Li ◽

Li Liu ◽

Zhong Xiang Li

Keyword(s):

Energy Efficiency ◽

Natural Gas ◽

Calculation Method ◽

Calorific Value ◽

Alternative Fuel ◽

Correction Coefficient ◽

Actual Situation ◽

Two Factors ◽

Natural Gas Vehicle ◽

Selection Of

There is no more in-depth research in the amount of alternative between natural gas and tradition fuel. The paper consider two factors about gas calorific value and vehicle level and put forward the fuel calorific value correction coefficient and vehicle energy efficiency correction coefficient. On this basis, the coefficient table and calculation method was established. The paper proved that because of the influence of the factors, equivalent ratio in the range of 1.13~1.67. The method can indicate the gas replacement more scientific and real, because of consider of the actual situation of application of the enterprise.The research can guide the selection of natural gas vehicle reasonable and scientific.

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Modeling Biomass Gasification: A New Approach to Utilize Renewable Sources of Energy

Volume 8: Energy Systems: Analysis, Thermodynamics and Sustainability; Sustainable Products and Processes ◽

10.1115/imece2008-68707 ◽

2008 ◽

Cited By ~ 4

Author(s):

M. Vaezi ◽

M. Passandideh-Fard ◽

M. Moghiman ◽

M. Charmchi

Keyword(s):

Selection Procedure ◽

Calorific Value ◽

Gas Temperature ◽

New Approach ◽

Wide Range ◽

Specific Biomass ◽

Thermochemical Equilibrium ◽

Biomass Materials ◽

Gasification Efficiency ◽

Selection Of

Thermochemical equilibrium modeling is the basis of the numerical method implemented in this study to predict the performance of a biomass gasifier. To validate the model, a close agreement is shown between numerical and experimental results. The model is then used in order to optimize the selection procedure of a specific biomass for a certain application. For this purpose, the minimum and maximum amount of carbon, hydrogen, and oxygen for 55 different biomass materials are extracted to calculate the range of variation of oxygen content and carbon/hydrogen ratio. The influences of such variations on syngas characteristics are then studied. Syngas characteristics are comprised of syngas calorific value, outlet gas temperature, gasification efficiency, and the volume of syngas obtained. The results are plotted in a generalized format that may be used for a wide range of biomass materials. These plots can be used for the selection of a biomass material based on desired conditions. Therefore, the developed model in this study provides a tool for design optimization of a biomass downdraft gasifier.

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Prioritization and selection of high fuelwood producing plant species at Boset District, Central Ethiopia: an ethnobotanical approach

Journal of Ethnobiology and Ethnomedicine ◽

10.1186/s13002-021-00474-9 ◽

2021 ◽

Vol 17 (1) ◽

Author(s):

Tinsae Bahru ◽

Berhane Kidane ◽

Amsalu Tolessa

Keyword(s):

Plant Species ◽

Sustainable Use ◽

Calorific Value ◽

Calotropis Procera ◽

Sampled Data ◽

Structured Interviews ◽

Acacia Senegal ◽

Cryptostegia Grandiflora ◽

Selection Of Species ◽

Selection Of

Abstract Background In Ethiopia, about 92.3% of all the fuelwood (firewood and/or charcoal) is consumed for cooking, heating and lighting purposes by domestic households and the demand is growing from 10 to 14%. However, there are little/no practical experiences or documented indigenous knowledge on how traditional people identify and select high fuelwood producing plant species with short rotation periods at Boset District. Therefore, the present study was aimed at: (1) selecting and documenting high fuelwood producing plant species at Boset District; (2) identifying major predictor variables that influence the prioritization and selection of species; and (3) develop a Generalized Linear Model (GLM) to predict the selection of species. Methods A total of 96 informants comprising 59 men and 37 women between the ages of 18 and 81 were sampled. Data were collected using structured interviews, guided field walk, discussions and field observations. Results Collected data indicated that 88.5% of the informants involved in firewood collection, while 90% practiced charcoal making. A total of 1533.60 Birr per household on average was earned annually from this activity. A total of 25 fuelwood producing plant species were identified and documented at Boset District. Of these, Acacia senegal, Acacia tortilis and Acacia robusta were the three best prioritized and selected indigenous high fuelwood producing species. Prosopis juliflora, Parthenium hysterophorus, Azadirachta indica, Calotropis procera, Cryptostegia grandiflora, Lantana camara and Senna occidentalis further grouped under introduced fuelwood species. Prediction of GLM assured sampled Kebeles and source of income generated from fuelwood species positively and significantly (p < 0.001) related to selection of species. Higher efficiency to provide energy and heat; little or no smoke or soot; easier to cut and split the wood and easier availability were some of the main selection criteria. Conclusions This study provides valuable information in selecting and documenting of high fuelwood producing plant species for proper management and sustainable use at Boset District. The three most selected species (A. senegal, A. tortilis and A. robusta) should be further evaluated at laboratory to determine their calorific value and combustion characteristics.

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The Evaluation of Coal, with Particular Reference to Small Coal for Steam Raising

Proceedings of the Institution of Mechanical Engineers ◽

10.1243/pime_proc_1934_127_022_02 ◽

1934 ◽

Vol 127 (1) ◽

pp. 341-354

Author(s):

E. S. Grumell

Keyword(s):

Calorific Value ◽

Steam Generation ◽

Reasonable Degree ◽

Alternative Method ◽

Slow Development ◽

Method Of Evaluation ◽

Selection Of

It is generally recognized that the sale and purchase of coal for steam generation on the basis of its calorific value would be more rational than the present methods. In the paper the advantages of the calorific value basis are briefly discussed, and reasons given for its relatively slow development. The non-uniformity of industrial coals makes it difficult to assess their value except in relatively large quantities. This has an important bearing on the selection of coal by the short boiler-trial method. Apart from the technical difficulties of attaining a reasonable degree of accuracy in a short boiler-trial, there must always be a doubt as to whether the sample tested was really representative. An alternative method of evaluation is described which enables larger and more representative quantities of coal to be examined. This method is based on accurate sampling and analysis, and is claimed to be less liable to error. At the same time it permits a greater number of types of coals to be investigated, thus giving the purchaser a wider choice, and increasing his knowledge of coals. In addition, the author provides a basis of control for subsequent deliveries. It is, in any case, strongly recommended as a check on any other method.

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Optimization and Selection of Solid Fuel Type in Sintering Process

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.303-306.2581 ◽

2013 ◽

Vol 303-306 ◽

pp. 2581-2584 ◽

Cited By ~ 1

Author(s):

Chun Yan Song ◽

Yong Liang Gui ◽

Bin Sheng Hu ◽

Quan Hui Li

Keyword(s):

Low Temperature ◽

Solid Fuel ◽

Calorific Value ◽

Sintering Process ◽

Degradation Index ◽

Temperature Reduction ◽

Coal Powder ◽

Coke Powder ◽

Selection Of ◽

Low Temperature Reduction

In order to use resonably fuel resources and reduce cost of manufacture, the effects of coke and coal powder on chemical coposition and metallurgical properties of sinter were studied with the iron ore blender as the iron-contained materials. Results shown that the reducibility at 900°C was slightly improved and the low temperature reduction degradation index was worsened with the coke powder as the solid fuel relative to coal powder under the equal calorific value condition. However, with the increasing of solid fuel ratio, the mechanical strength and low temperature reduction degradation index was improved.

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The selection of optimal conditions for the process of obtaining humic acid from brown coal

E3S Web of Conferences ◽

10.1051/e3sconf/201910802020 ◽

2019 ◽

Vol 108 ◽

pp. 02020

Author(s):

Edyta Janeba-Bartoszewicz ◽

Dawid Romek ◽

Jarosław Selech ◽

Jacek Marcinkowski

Keyword(s):

Humic Acid ◽

Brown Coal ◽

Mixing Time ◽

Calorific Value ◽

Hard Coal ◽

Optimal Conditions ◽

Optimum Conditions ◽

Humus Substances ◽

Complexing Properties ◽

Selection Of

The type of plant substance from which brown coal is formed and the conditions in which it forms largely influence its characteristics and properties. On account of a lower degree of coalification and calorific value compared to hard coal and a high content of humic substances, brown coal is becoming a valuable fertiliser component. Humic acids contained in brown coal are also found in the soil’s humus substances, and their beneficial sorptive and complexing properties are a factor speaking in favour of their use both in agriculture and in other branches of the economy. The article presents the manner of preparing a sample of brown coal in order to determine the content of humic acid intended in particular for use in making chemical fertilisers and for other applications, particularly in agriculture. The optimum conditions in which the amount of humic acid in the sample is the highest were determined. The influence of the proportions of water, KOH, and brown coal, temperature, and mixing time on the solubility of the sample of brown coal was analysed. The solutions were mixed in mixers built especially for this purpose. The solubility of brown coal in the prepared solutions was controlled UV-ViS spectrophotometrically.

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Numerical Simulation for the Combustion Chamber of a Reference Calorimeter

Processes ◽

10.3390/pr8050575 ◽

2020 ◽

Vol 8 (5) ◽

pp. 575

Author(s):

José Eli Eduardo González-Durán ◽

Marco Antonio Zamora-Antuñano ◽

Leonel Lira-Cortés ◽

Juvenal Rodríguez-Reséndiz ◽

Juan Manuel Olivares-Ramírez ◽

...

Keyword(s):

Combustion Chamber ◽

Mass Fraction ◽

Combustion Process ◽

Calorific Value ◽

Chemical Kinetic ◽

Chamber Height ◽

Kinetic Mechanisms ◽

Skeletal Model ◽

Step Mechanism ◽

Selection Of

This paper focuses on the numerical modeling of the effect of the height of a combustion chamber on the development of a reference calorimeter whose objective is to measure the calorific value of natural gas. The impacts of temperature, velocity, and mass fraction on the exhaust gases were evaluated by varying the height of the combustion chamber. The eddy dissipation concept (EDC) approach was used to model combustion with two different chemical kinetic mechanisms: one with three steps, called the three-step mechanism defined by default in the software used, and second skeletal model, which consists of 41 steps, through the ChemKin-import file with 16 species. The main result of this study is the selection of a combustion chamber height for the reference calorimeter that produces the best performance in the combustion process, which is 70 mm, as well as the main differences in using a three-step mechanism and a skeletal model to simulate an oxy-fuel combustion reaction.

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Cognitive gadgets and cognitive priors

Behavioral and Brain Sciences ◽

10.1017/s0140525x19000992 ◽

2019 ◽

Vol 42 ◽

Author(s):

Gian Domenico Iannetti ◽

Giorgio Vallortigara

Keyword(s):

Cognitive Neuroscience ◽

Selection Of

Abstract Some of the foundations of Heyes’ radical reasoning seem to be based on a fractional selection of available evidence. Using an ethological perspective, we argue against Heyes’ rapid dismissal of innate cognitive instincts. Heyes’ use of fMRI studies of literacy to claim that culture assembles pieces of mental technology seems an example of incorrect reverse inferences and overlap theories pervasive in cognitive neuroscience.

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Note on Selection of Coordinate Systems for Geodynamics

International Astronomical Union Colloquium ◽

10.1017/s0252921100051174 ◽

1975 ◽

Vol 26 ◽

pp. 395-407

Author(s):

S. Henriksen

Keyword(s):

Sea Level ◽

The Other ◽

Coordinate Systems ◽

Mean Sea Level ◽

The Earth ◽

The One ◽

Static Systems ◽

Selection Of

The first question to be answered, in seeking coordinate systems for geodynamics, is: what is geodynamics? The answer is, of course, that geodynamics is that part of geophysics which is concerned with movements of the Earth, as opposed to geostatics which is the physics of the stationary Earth. But as far as we know, there is no stationary Earth – epur sic monere. So geodynamics is actually coextensive with geophysics, and coordinate systems suitable for the one should be suitable for the other. At the present time, there are not many coordinate systems, if any, that can be identified with a static Earth. Certainly the only coordinate of aeronomic (atmospheric) interest is the height, and this is usually either as geodynamic height or as pressure. In oceanology, the most important coordinate is depth, and this, like heights in the atmosphere, is expressed as metric depth from mean sea level, as geodynamic depth, or as pressure. Only for the earth do we find “static” systems in use, ana even here there is real question as to whether the systems are dynamic or static. So it would seem that our answer to the question, of what kind, of coordinate systems are we seeking, must be that we are looking for the same systems as are used in geophysics, and these systems are dynamic in nature already – that is, their definition involvestime.

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