Pyrolysis Characteristics and Kinetics of Cassava Residues

2014 ◽  
Vol 953-954 ◽  
pp. 325-329
Author(s):  
Jin Wei Jia ◽  
Di Yang ◽  
He Long Hui ◽  
Xing Min Fu ◽  
Lu Liu ◽  
...  
Keyword(s):  
Activation Energy ◽  
Kinetic Parameters ◽  
Fixed Bed ◽  
The Other ◽  
Fixed Bed Reactor ◽  
Biomass Feedstock ◽  
Pyrolysis Characteristics ◽  
Three Samples ◽  
Bio Oil ◽  
Kinetics Of

The aims of this work were to investigate the influence of feedstock properties of different part of cassava residues (cassava rhizome (CR), cassava stalk (CS) and cassava leaf (CL)) and operating temperatures on the pyrolysis characteristics and the kinetic parameters. Pyrolysis experiments of three selected biomass feedstock were conducted using a fixed-bed reactor. It was shown that the bio-oil yield of cassava stalk reached the maxima at 600°C, and the char yield reduced with the temperature, whereas the gas yield increased with temperature. The cassava rhizome presented higher thermochemical reactivity than the other samples. The activation energy of cassava stalks was 37.57 kJ / mol and that of cassava rhizome (39.42 kJ / mol) increased slightly. The activation energy of cassava leaf (22.85 kJ / mol) was lowest of the three samples.

scholarly journals Influence of Substrate Concentration on Kinetic Parameters of Ethanol Dehydration in MFI and CHA Zeolites and Relation of These Kinetic Parameters to Acid–Base Properties

Catalysts ◽  
2022 ◽  
Vol 12 (1) ◽  
pp. 51
Author(s):  
Pavel Čičmanec ◽  
Jiří Kotera ◽  
Jan Vaculík ◽  
Roman Bulánek
Keyword(s):  
Activation Energy ◽  
Kinetic Parameters ◽  
Catalyst Deactivation ◽  
Fixed Bed ◽  
Fixed Bed Reactor ◽  
Ethanol Dehydration ◽  
Acid Base ◽  
Diffusion Limitations ◽  
Zeolite Lattice ◽  
Base Properties

The catalytic activity of zeolites is often related to their acid–base properties. In this work, the relationship between the value of apparent activation energy of ethanol dehydration, measured in a fixed bed reactor and by means of a temperature-programmed surface reaction (TPSR) depending on the amount of ethanol in the zeolite lattice and the value of activation energy of H/D exchange as a measure of acid–base properties of MFI and CHA zeolites, was studied. Tests in a fixed bed reactor were unable to provide reliable reaction kinetics data due to internal diffusion limitations and rapid catalyst deactivation. Only the TPSR method was able to provide activation energy values comparable to the activation energy values obtained from the H/D exchange rate measurements. In addition, for CHA zeolite, it has been shown that the values of ethanol dehydration activation energies depend on the amount of ethanol in the CHA framework, and this effect can be attributed to the substrate clustering effects supporting the deprotonation of zeolite Brønsted centers.

scholarly journals Pyrolysis characteristics and kinetics of β-cyclodextrin and its two derivatives

2015 ◽  
Vol 17 (4) ◽  
pp. 1-4 ◽  
Author(s):  
Guangyong Zhu ◽  
Zuobing Xiao ◽  
Rujun Zhou ◽  
Yunwei Niu
Keyword(s):  
Activation Energy ◽  
Thermal Stability ◽  
Systematic Research ◽  
Heating Process ◽  
Thermal Stabilities ◽  
Exponential Factor ◽  
Pyrolysis Characteristics ◽  
Three Samples ◽  
Three Stages ◽  
Kinetics Of

Abstract β-cyclodextrin (β-CD) and its derivatives have been widely used to prepare inclusion complexes. However, systematic research on their thermal stabilities, pyrolysis characteristics and kinetics has rarely been reported. In this paper, thermogravimetric analysis was employed to investigate β-cyclodextrin and its two derivatives, 2-Hydroxypropyl-β-cyclodextrin (HP-β-CD) and monochlorotriazinyl-β-cyclodextrin (MCT-β-CD). The pyrolysis characteristics and kinetic parameters were obtained. The results show that three stages can be distinguished during the heating process of the above three samples. The temperature of initial decomposition of HP-β-CD (309.5°C is higher than that of β-CD (297.8°C), while the temperature of initial decomposition of MCT-β-CD (231.4°C) is lower than that of β-CD. For the three cyclodextrins, the thermal stability in descending order is HP-β-CD, β-CD and MCT-HP-β-CD. The activation energy values are 350.6, 303.3 and 113.9 KJ/mol, and the pre-exponential factor values are 1.11×1031, 1.37×1026 and 1.39×1010 for β-CD, HP-β-CD and MCT-β-CD respectively.

Pyrolysis Characteristics and Kinetics of the Oil Shale in Daqing Exploratory Area

2014 ◽  
Vol 521 ◽  
pp. 666-670
Author(s):  
Yun Xia Bian ◽  
De Min He ◽  
Guo Zhu Kuang ◽  
Qiu Min Zhang
Keyword(s):  
Activation Energy ◽  
Constant Temperature ◽  
Oil Shale ◽  
Fixed Bed ◽  
Shale Oil ◽  
Pyrolysis Characteristics ◽  
Oil Shale Pyrolysis ◽  
Reaction Activation Energy ◽  
Kinetics Of ◽  
Temperature Time

Proximate analysis, ultimate analysis and CO2of carbonate were determinated for the aboveground oil shale in Daqing exploratory area. The experiments of pyrolysis of Daqing oil shale were carried out in a fixed-bed reactor in order to study the influence of the pyrolysis temperature and the constant temperature time on oil shale pyrolysis characteristics. The results show that the effect of the pyrolysis is optimal under the conditions of 500°C and the constant temperature time for 20 min, with the yield of shale oil for 28.78% (the yield based on kerogen, similarly hereinafter). The mechanism of the oil shale pyrolysis was discussed. The pyrolysis reaction kinetics of oil shale was studied combining the experimental results of fixed-bed pyrolysis. The reaction activation energy is 28.92 kJ/mol during generating the shale oil process, while the reaction activation energy is 11.21 kJ/mol during generating char process. The yield curve of shale oil changing with the temperature was fitted to compare with the measured value with the constant temperature time for 20 min according to the pyrolysis kinetic parameters.

Role of filter media in an anaerobic fixed-bed reactor

1995 ◽  
Vol 31 (9) ◽  
pp. 137-144 ◽  
Author(s):  
T. Miyahara ◽  
M. Takano ◽  
T. Noike
Keyword(s):  
Anaerobic Bacteria ◽  
Fixed Bed ◽  
Methanogenic Bacteria ◽  
The Other ◽  
Fixed Bed Reactor ◽  
Filter Media ◽  
Fixed Bed Reactors ◽  
Attached Bacteria ◽  
The Relationship

The relationship between the filter media and the behaviour of anaerobic bacteria was studied using anaerobic fixed-bed reactors. At an HRT of 48 hours, the number of suspended acidogenic bacteria was higher than those attached to the filter media. On the other hand, the number of attached methanogenic bacteria was more than ten times as higher than that of suspended ones. The numbers of suspended and deposited acidogenic and methanogenic bacteria in the reactor operated at an HRT of 3 hours were almost the same as those in the reactor operated at an HRT of 48 hours. Accumulation of attached bacteria was promoted by decreasing the HRT of the reactor. The number of acidogenic bacteria in the reactor packed sparsely with the filter media was higher than that in the closely packed reactor. The number of methanogenic bacteria in the sparsely packed reactor was lower than that in the closely packed reactor.

scholarly journals Bio-Oil Characterizations of Spirulina Platensis Residue (SPR) Pyrolysis Products for Renewable Energy Development

2020 ◽  
Vol 849 ◽  
pp. 47-52
Author(s):  
Siti Jamilatun ◽  
Aster Rahayu ◽  
Yano Surya Pradana ◽  
Budhijanto ◽  
Rochmadi ◽  
...  
Keyword(s):  
Renewable Energy ◽  
Spirulina Platensis ◽  
Pyrolysis Temperature ◽  
Renewable Energy Sources ◽  
Fixed Bed ◽  
Fixed Bed Reactor ◽  
Oil Yield ◽  
Optimum Temperature ◽  
Pyrolysis Products ◽  
Bio Oil

Nowadays, energy consumption has increased as a population increases with socio-economic developments and improved living standards. Therefore, it is necessary to find a replacement for fossil energy with renewable energy sources, and the potential to develop is biofuels. Bio-oil, water phase, gas, and char products will be produced by utilizing Spirulina platensis (SPR) microalgae extraction residue as pyrolysis raw material. The purpose of this study is to characterize pyrolysis products and bio-oil analysis with GC-MS. Quality fuel is good if O/C is low, H/C is high, HHV is high, and oxygenate compounds are low, but aliphatic and aromatic are high. Pyrolysis was carried out at a temperature of 300-600°C with a feed of 50 grams in atmospheric conditions with a heating rate of 5-35°C/min, the equipment used was a fixed-bed reactor. The higher the pyrolysis temperature, the higher the bio-oil yield will be to an optimum temperature, then lower. The optimum temperature of pyrolysis is 550°C with a bio-oil yield of 23.99 wt%. The higher the pyrolysis temperature, the higher the H/C, the lower O/C. The optimum condition was reached at a temperature of 500°C with the values of H/C, and O/C is 1.17 and 0.47. With an increase in temperature of 300-600°C, HHV increased from 11.64 MJ/kg to 20.63 MJ/kg, the oxygenate compound decreased from 85.26 to 37.55 wt%. Aliphatics and aromatics increased, respectively, from 5.76 to 36.72 wt% and 1.67 to 6.67 wt%.

scholarly journals Pyrolysis Characteristics of Undervalued Wood Varieties in the Portuguese Charcoal Sector

Energies ◽  
2021 ◽  
Vol 14 (9) ◽  
pp. 2537
Author(s):  
Felix Charvet ◽  
Felipe Silva ◽  
Luís Ruivo ◽  
Luís Tarelho ◽  
Arlindo Matos ◽  
...  
Keyword(s):  
Large Scale ◽  
Fixed Bed ◽  
Management Control ◽  
Fixed Bed Reactor ◽  
Fuel Load ◽  
Charcoal Production ◽  
Pyrolysis Characteristics ◽  
Major Market ◽  
Burnt Wood ◽  
Fuel Particles

Charcoal production in Portugal is mostly based on the valorization of woody residues from cork oak and holm oak, the latter being considered a reference feedstock in the market. Nevertheless, since wildfire prevention became a priority in Portugal, after the recent dramatic wildfires, urgent actions are being conducted to reduce the fuel load in the forests, which is increasing the amount of biomass that is available for valorization. Additionally, biomass residues from agriculture, forest management, control of invasive species, partially burnt wood from post-fire recovery actions, and waste wood from storm devastated forests need also to be considered within the national biomass valorization policies. This has motivated the present work on whether the carbonization process can be used to valorize alternative woody biomasses not currently used on a large scale. For this purpose, slow pyrolysis experiments were carried out with ten types of wood, using a fixed bed reactor allowing the controlled heating of large fuel particles at 0.1 to 5 °C/min and final temperatures within 300–450 °C. Apart from an evaluation of the mass balance of the process, emphasis was given to the properties of the resulting charcoals considering its major market in Portugal—barbecue charcoal for both recreational and professional purposes.

Thermogravimetric Analysis of Glucose-Based and Fructose-Based Carbohydrates

2013 ◽  
Vol 805-806 ◽  
pp. 265-268 ◽  
Author(s):  
Fang Ming Cui ◽  
Xiao Yuan Zhang ◽  
Li Min Shang
Keyword(s):  
Activation Energy ◽  
Thermogravimetric Analysis ◽  
Kinetic Parameters ◽  
Degree Of Polymerization ◽  
Experiment Data ◽  
Pyrolysis Characteristics ◽  
The Difference ◽  
Kinetic Calculations

Thermogravimetric analysis (TGA) was employed to study the pyrolysis characteristics of four glucose-based and three fructose-based carbohydrates. Kinetic parameters were calculated based on the experiment data. The results indicated that the starting and maximal pyrolysis temperatures of the glucose-based carbohydrates were increased steadily as the rising of their degree of polymerization (DP). The fructose-based carbohydrates exhibited similar pyrolysis behaviors as the glucose-based carbohydrates, but the difference was smaller. Kinetic calculations revealed that the activation energy values of the glucose-based carbohydrates were higher than those of the fructose-based carbohydrates, indicating the glucose-based carbohydrates were more difficult to decompose than the fructose-based carbohydrates.

Comparison of the Yield and Properties of Bio-Oil Produced by Slow and Fast Pyrolysis of Rice Husks and Coconut Shells

2014 ◽  
Vol 625 ◽  
pp. 626-629 ◽  
Author(s):  
Mandy Su Zan Gui ◽  
Seyed Amirmostafa Jourabchi ◽  
Hoon Kiat Ng ◽  
Suyin Gan
Keyword(s):  
Maximum Yield ◽  
Fast Pyrolysis ◽  
Fixed Bed ◽  
Fixed Bed Reactor ◽  
Rice Husks ◽  
Standard Procedures ◽  
Bio Oil ◽  
American Society ◽  
Coconut Shells ◽  
Lower Water Content

Slow pyrolysis (SP) and fast pyrolysis (FP) of rice husks, coconut shells and their mixtures were studied in a fixed bed reactor. The objectives of this study were to compare the yields and properties of bio-oils produced using SP and FP methods within a pyrolysis temperature range of 400 °C to 600 °C. Three different biomass compositions, 100% rice husks (RH), 100% coconut shells (CS) and a mixture of 50% rice husks with 50% of coconut shells (RH50/CS50) were experimented. In SP, the maximum yield of bio-oil for RH, CS and RH50/CS50 were 45.45%, 37.01%, 38.29% at temperatures of 550 °C, 500 °C and 600 °C respectively. As for FP, the maximum bio-oil yield obtained for RH, CS and RH50/CS50 were 50.52%, 40.14% and 42.25% at temperatures of 500 °C, 600 °C and 550 °C respectively. At these optimum pyrolysis temperatures, the percentage differences in bio oil yields for SP and FP were 10.57%, 8.11% and 9.83% for RH, CS and RH50/CS50 respectively. Based on American Society for Testing and Materials (ASTM) standard procedures, the properties of bio-oil were characterised and it was found that the bio oil produced by FP at optimum temperatures were less acidic, higher density, lower water content and viscosity as compared to the bio-oil produced by SP method for all biomass compositions.

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