Oxytree Pruned Biomass Torrefaction: Mathematical Models of the Influence of Temperature and Residence Time on Fuel Properties Improvement

Biowaste generated in the process of Oxytree cultivation and logging represents a potential source of energy. Torrefaction (a.k.a. low-temperature pyrolysis) is one of the methods proposed for the valorization of woody biomass. Still, energy is required for the torrefaction process during which the raw biomass becomes torrefied biomass with fuel properties similar to those of lignite coal. In this work, models describing the influence of torrefaction temperature and residence time on the resulting fuel properties (mass and energy yields, energy densification ratio, organic matter and ash content, combustible parts, lower and higher heating values, CHONS content, H:C and O:C ratios) were proposed according to the Akaike criterion. The degree of the models’ parameters matching the raw data expressed as the determination coefficient (R2) ranged from 0.52 to 0.92. Each model parameter was statistically significant (p < 0.05). Estimations of the value and quantity of the produced torrefied biomass from 1 Mg of biomass residues were made based on two models and a set of simple assumptions. The value of torrefied biomass (€123.4·Mg−1) was estimated based on the price of commercially available coal fuel and its lower heating value (LHV) for biomass moisture content of 50%, torrefaction for 20 min at 200 °C. This research could be useful to inform techno-economic analyses and decision-making process pertaining to the valorization of pruned biomass residues.

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Oxytree Pruned Biomass Torrefaction - Mathematical Models of the Influence of Temperature and Residence Time on Fuel Properties Improvement

10.20944/preprints201906.0126.v1 ◽

2019 ◽

Author(s):

Kacper Świechowski ◽

Marek Liszewski ◽

Przemysław Bąbelewski ◽

Jacek A. Koziel ◽

Andrzej Białowiec

Keyword(s):

Residence Time ◽

Fuel Properties ◽

Heating Value ◽

Biomass Residues ◽

Coal Fuel ◽

Lower Heating Value ◽

Akaike Criterion ◽

Economic Analyses ◽

Low Temperature Pyrolysis ◽

Lower Heating

Biowaste generated in the process of Oxytree cultivation and logging represents a potential source of energy. Torrefaction (a.k.a. low-temperature pyrolysis) is one of the methods proposed for the valorization of woody biomass. Still, energy is required for the torrefaction process during which the raw biomass becomes biochar with fuel properties similar to lignite coal. In this work, models describing the influence of torrefaction temperature and residence time on the resulting fuel properties (mass and energy yields, energy densification ratio, organic matter and ash content, combustible parts, lower and higher heating values, CHONS content, H:C and O:C ratios) were proposed according to the Akaike criterion. The degree of the models’ parameters matching the raw data expressed as the determination coefficient (R2) ranged from 0.52 to 0.92. Each model parameter was statistically significant (p<0.05). Estimations of the value and quantity of the produced biochar from 1 Mg of biomass residues were made based on two models and a set of simple assumptions. The value of torrefied biochar (€123.4·Mg-1) was estimated based on the price of commercially available coal fuel and its lower heating value (LHV) for biomass moisture content of 50%, torrefaction for 20 min at 200 °C. This research could be useful to inform techno-economic analyses and decision-making process pertaining to the valorization of pruned biomass residues.

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Waste to Carbon: Biocoal from Elephant Dung as New Cooking Fuel

Energies ◽

10.3390/en12224344 ◽

2019 ◽

Vol 12 (22) ◽

pp. 4344 ◽

Cited By ~ 11

Author(s):

Stępień ◽

Świechowski ◽

Hnat ◽

Kugler ◽

Stegenta-Dąbrowska ◽

...

Keyword(s):

Rural Areas ◽

Fuel Properties ◽

Technological Parameters ◽

Scanning Calorimetry ◽

High Heating Value ◽

Scale Experiment ◽

Economic Analyses ◽

Low Temperature Pyrolysis ◽

The Impact ◽

Elephant Dung

The paper presents, for the first time, the results of fuel characteristics of biochars from torrefaction (a.k.a., roasting or low-temperature pyrolysis) of elephant dung (manure). Elephant dung could be processed and valorized by torrefaction to produce fuel with improved qualities for cooking. The work aimed to examine the possibility of using torrefaction to (1) valorize elephant waste and to (2) determine the impact of technological parameters (temperature and duration of the torrefaction process) on the waste conversion rate and fuel properties of resulting biochar (biocoal). In addition, the influence of temperature on the kinetics of the torrefaction and its energy consumption was examined. The lab-scale experiment was based on the production of biocoals at six temperatures (200–300 °C; 20 °C interval) and three process durations of the torrefaction (20, 40, 60 min). The generated biocoals were characterized in terms of moisture content, organic matter, ash, and higher heating values. In addition, thermogravimetric and differential scanning calorimetry analyses were also used for process kinetics assessment. The results show that torrefaction is a feasible method for elephant dung valorization and it could be used as fuel. The process temperature ranging from 200 to 260 °C did not affect the key fuel properties (high heating value, HHV, HHVdaf, regardless of the process duration), i.e., important practical information for proposed low-tech applications. However, the higher heating values of the biocoal decreased above 260 °C. Further research is needed regarding the torrefaction of elephant dung focused on scaling up, techno-economic analyses, and the possibility of improving access to reliable energy sources in rural areas.

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Characteristic Properties of Alternative Biomass Fuels

Energies ◽

10.3390/en13061448 ◽

2020 ◽

Vol 13 (6) ◽

pp. 1448 ◽

Cited By ~ 5

Author(s):

Martin Lisý ◽

Hana Lisá ◽

David Jecha ◽

Marek Baláš ◽

Peter Križan

Keyword(s):

Renewable Energy ◽

Water Content ◽

Elemental Analysis ◽

Renewable Energy Sources ◽

Fuel Properties ◽

Energy Sources ◽

Heating Value ◽

Lower Heating Value ◽

Lower Heating

Biomass is one of the most promising renewable energy sources because it enables energy accumulation and controlled production. With this, however, the demand for biofuels grows and thus there is an effort to expand their portfolio. Nevertheless, to use a broader range of biofuels, it is necessary to know their fuel properties, such as coarse and elemental analysis, or lower heating value. This paper presents the results of testing the fuel properties of several new, potentially usable biofuels, such as quinoa, camelina, crambe, and safflower, which are compared with some traditional biofuels (wood, straw, sorrel, hay). Moreover, the results of the determination of water content, ash, and volatile combustible content of these fuels are included, along with the results of the elemental analysis and the determination of higher and lower heating values. Based on these properties, it is possible to implement designs of combustion plants of different outputs for these fuels.

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Proof-of-the-Concept of Spent Mushrooms Compost Torrefaction - Preliminary Studies of Process Kinetics and the Influence of Temperature and Duration on Calorific Value of the Biochar

10.20944/preprints201907.0212.v1 ◽

2019 ◽

Author(s):

Ewa Syguła ◽

Jacek Koziel ◽

Andrzej Bialowiec

Keyword(s):

Calorific Value ◽

Energy Yield ◽

Total Production ◽

Heating Value ◽

Process Duration ◽

Mushroom Production ◽

Coal Fuel ◽

Duration Time ◽

Low Temperature Pyrolysis ◽

The Eu

Poland is the 3rdproducer of mushrooms in the world. Mushroom production in Poland accounts for nearly 25% of the total production in the EU, and it is still growing. One type of waste generated during mushroom production is mushroom spent compost (MSC), with a 5:1 (MSC: mushrooms) production rate. We investigated valorizing the MSC to produce fuel via torrefaction (‘roasting’, a.k.a. low-temperature pyrolysis). Specifically, we developed models for the MSC torrefaction kinetics using thermogravimetric analyses (TGA) and the effects of torrefaction temperature (200~300 °C) and process duration time (20~60 min) on the resulting biochar (fuel) properties. The estimated activation energy value of MSC torrefaction was 22.3 kJ.mol-1. The highest higher heating value(HHV) = 17.9 MJ.kg-1d.m. was found for 280 °C (60 min torrefaction time). The temperature of torrefaction significantly (p<0.05) increased the HHVfor constant process duration. The torrefaction duration time significantly (p<0.05) increased the HHVfor 220 °C and decreased HHVfor 300 °C. The highest mass yield 98.5% was found for 220 °C (60 min), while the highest energy yield was found for 280 °C (60 min). In addition, estimations of the value (€132.3·Mg-1d.m. or 27.7 €·Mg-1w.m) and quantity of resulting biochar (from torrefied MSC with 65.3% moisture content) were made based on the 280°C (60 min) torrefaction variant, assuming the price of commercially available coal fuel. We have shown a concept for an alternative utilization of abundant biowaste (MSC). The initial economic evaluation showed that MSC torrefaction might be profitable. This research provides a basis for alternative use of an abundant biowaste and can help charting improved, sustainable mushroom production.

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Combustion Study of Polyoxymethylene Dimethyl Ethers and Diesel Blend Fuels on an Optical Engine

Energies ◽

10.3390/en14154608 ◽

2021 ◽

Vol 14 (15) ◽

pp. 4608

Author(s):

Jingjing He ◽

Hao Chen ◽

Xin Su ◽

Bin Xie ◽

Quanwei Li

Keyword(s):

Soot Formation ◽

Comprehensive Evaluation ◽

Chemical Properties ◽

Heating Value ◽

Optical Engine ◽

Leading Role ◽

Combustion Duration ◽

Polyoxymethylene Dimethyl Ethers ◽

Lower Heating Value ◽

Lower Heating

Polyoxymethylene dimethyl ethers (PODE) are a newly appeared promising oxygenated alternative that can greatly reduce soot emissions of diesel engines. The combustion characteristics of the PODE and diesel blends (the blending ratios of PODE are 0%, 20%, 50% and 100% by volume, respectively) are investigated based on an optical engine under the injection timings of 6, 9, 12 and 15-degree crank angles before top dead center and injection pressures of 100 MPa, 120 MPa and 140 MPa in this study. The results show that both the ignition delay and combustion duration of the fuels decrease with the increasing of PODE ratio in the blends. However, in the case of the fuel supply of the optical engine being fixed, the heat release rate, cylinder pressure and temperature of the blend fuels decrease with the PODE addition due to the low lower heating value of PODE. The addition of PODE in diesel can significantly reduce the integrated natural flame luminosity and the soot formation under all injection conditions. When the proportion of the PODE addition is 50% and 100%, the chemical properties of the blends play a leading role in soot formation, while the change of the injection conditions have an inconspicuous effect on it. When the proportion of the PODE addition is 20%, the blend shows excellent characteristics in a comprehensive evaluation of combustion and soot reduction.

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Correlations to Predict Elemental Compositions and Heating Value of Torrefied Biomass

Energies ◽

10.3390/en11092443 ◽

2018 ◽

Vol 11 (9) ◽

pp. 2443 ◽

Cited By ~ 12

Author(s):

Mahmudul Hasan ◽

Yousef Haseli ◽

Ernur Karadogan

Keyword(s):

Carbon Content ◽

Hydrogen Content ◽

Woody Biomass ◽

Coefficient Of Determination ◽

Mass Yield ◽

Solid Mass ◽

Empirical Correlations ◽

Heating Value ◽

Torrefied Biomass ◽

Data Points

Measurements reported in the literature on ultimate analysis of various types of torrefied woody biomass, comprising 152 data points, have been compiled and empirical correlations are developed to predict the carbon content, hydrogen content, and heating value of a torrefied wood as a function of solid mass yield. The range of torrefaction temperature, residence time and solid yield of the collected data is 200–300 °C, 5–60 min and 58–97%, respectively. Two correlations are proposed for carbon content with a coefficient of determination ( R 2 ) of 81.52% and 89.86%, two for hydrogen content with R 2 of 79.01% and 88.45%, and one for higher heating value with R 2 of 92.80%. The root mean square error (RMSE) values of the proposed correlations are 0.037, 0.028, 0.059, 0.043 and 0.023, respectively. The predictability of the proposed relations is examined with an additional set of experimental data and compared with the existing correlations in the literature. The new correlations can be used as a useful tool when designing torrefaction plants, furnaces, or gasifiers operating on torrefied wood.

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Biodiesel Effects on Influencing Parameters of Brake Fuel Conversion Efficiency in a Medium Duty Diesel Engine

Journal of Engineering for Gas Turbines and Power ◽

10.1115/1.4001086 ◽

2010 ◽

Vol 132 (12) ◽

Cited By ~ 6

Author(s):

Joshua A. Bittle ◽

Jesse K. Younger ◽

Timothy J. Jacobs

Keyword(s):

Conversion Efficiency ◽

Energy Content ◽

Combustion Efficiency ◽

Operating Conditions ◽

Biodiesel Fuel ◽

Mass Energy ◽

Fuel Conversion ◽

Heating Value ◽

Lower Heating Value ◽

Lower Heating

Biodiesel remains an alternative fuel of interest for use in diesel engines. A common characteristic of biodiesel, relative to petroleum diesel, is a lowered heating value (or per mass energy content of the fuel). For same torque engine comparisons, the lower heating value translates into a higher brake specific fuel consumption (amount of fuel consumed per unit of power produced). The efficiency at which fuel energy converts into work energy, however, may remain unchanged. In this experimental study, evaluating nine unique engine operating conditions, the brake fuel conversion efficiency (an assessor of fuel energy to work energy efficiency) remains unchanged between 100% petroleum diesel fuel and 100% biodiesel fuel (palm olein) at all conditions, except for high load conditions. Several parameters may affect the brake fuel conversion efficiency, including heat loss, mixture properties, pumping work, friction, combustion efficiency, and combustion timing. This article describes a study that evaluates how the aforementioned parameters may change with the use of biodiesel and petroleum diesel, and how these parameters may result in differences in the brake fuel conversion efficiency.

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Lower Heating Value of Jet Fuel from Hydrocarbon Class Concentration Data and Thermo-Chemical Reference Data: An Uncertainty Quantification

10.33774/chemrxiv-2021-knj2g ◽

2021 ◽

Author(s):

Randall Boehm ◽

Zhibin Yang ◽

David Bell ◽

John Feldhausen ◽

Joshua Heyne

Keyword(s):

Jet Fuel ◽

Confidence Bands ◽

Heats Of Formation ◽

Concentration Data ◽

Heating Value ◽

Accuracy And Precision ◽

Lower Heating Value ◽

Detailed Assessment ◽

Value Net ◽

Lower Heating

A detailed assessment is presented on the calculation and uncertainty of the lower heating value (net heat of combustion) of conventional and sustainable aviation fuels, from hydrocarbon class concentration measurements, reference molecular heats of formation, and the uncertainties of these reference heats of formation. Calculations using this paper’s method and estimations using ASTM D3338 are reported for 17 fuels of diverse compositions and compared against reported ASTM D4809 measurements. All the calculations made by this method and the reported ASTM D4809 measurements agree (i.e., within 95% confidence intervals). The 95% confidence interval of the lower heating value of fuel candidates that are comprised entirely of normal- and iso-alkanes is less than 0.1 MJ/kg by the method described here, while high cyclo-alkane content leads to 95% confidence bands that approach 0.2 MJ/kg. Taking a possible bias into account, the accuracy and precision of the method described in this work could be as high as 0.23 MJ/kg for some samples.

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The Technological Investigations Of Manufacturing Of Energy Chips

Environment Technology Resources Proceedings of the International Scientific and Practical Conference ◽

10.17770/etr2011vol1.908 ◽

2015 ◽

Vol 1 ◽

pp. 220

Author(s):

Ziedonis Miklašēvičs

Keyword(s):

Moisture Content ◽

Dry Mass ◽

Quality Parameters ◽

Heating Value ◽

Long Term Storage ◽

Lower Heating Value ◽

Term Storage ◽

Lower Heating

The methodology in Latvia forest industry provide to determine the quality of energy chips only in long- term storage places before selling. Due to the lack of hard empirical data about the quality parameters of energy chips in different phases of manufacturing process, this research paper consists of: - the identification and analyses of the factors that influenced the values of energy chips quality features such as: bulk density, moisture content, ash content, higher and lower heating value according to actual moisture content and per dry mass of the chips; - the methodology for determination the quality parameters of energy chips by analysis the wood moisture content and by choice the method of the manufacturing of energy chips.

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EXERGY-BASED INVESTIGATION OF A COAL-FIRED ALLAM CYCLE

E3S Web of Conferences ◽

10.1051/e3sconf/201913701018 ◽

2019 ◽

Vol 137 ◽

pp. 01018 ◽

Cited By ~ 1

Author(s):

Jing Luo ◽

Ogechi Emelogu ◽

Tatiana Morosuk ◽

George Tsatsaronis

Keyword(s):

Fossil Fuels ◽

Coal Gasification ◽

High Efficiency ◽

Cycle Performance ◽

Energetic Efficiency ◽

Component Level ◽

Lower Efficiency ◽

Heating Value ◽

Lower Heating Value ◽

Lower Heating

Allam cycle is a novel cycle that capitalizes on the unique thermodynamic properties of supercritical CO2 and the advantages of oxy-combustion for power generation. It is a high-pressure supercritical carbon dioxide cycle designed to combust fossil fuels such as natural gas or syngas (from coal gasification systems) with complete CO2 separation at a high-efficiency and zero atmospheric emissions. This semi-closed cycle produces sequestration-ready/pipeline quality CO2 by-product, and thus eliminates the need for additional CO2-capture system. The Coal-fueled Allam cycle is targeted to deliver between 51-52% net efficiency (lower heating value) for coal gasification. In this study, the expected energetic efficiency is verified by simulating the system in Ebsilon professional software and the result showed that the net efficiency of the simulated coal-fired plant is 30.7%, which is significantly lower than the targeted value. The lower efficiency maybe as a result of the missing heat integration in the system, the high power demand of the oxidant compressor and CO2 compressors. And an exergy analysis based on published cycle data is employed, to investigate the cycle performance, identify the sources of the cycle’s thermodynamic inefficiencies at the component level; a sensitivity analysis is also performed to study the effects of selected thermodynamic parameters on the overall performance of the coal-fired Allam cycle.

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