Existence of Synergistic Effects During Co-pyrolysis of Petroleum Coke and Wood Pellet

Abstract This study attempts to comprehend the thermal degradation behaviour of different blends of petroleum coke (denoted as PC) and wood pellets (denoted as WP) (1:0, 3:1, 1:1. 1:3 and 0:1) using thermogravimetric (denoted as TG) analysis under N2 atmosphere with constant particle size range of 500–850 µm and at constant heating rate of 5 °C/min. TG experiments indicated that it is difficult to predict the pyrolysis characteristics of their blends accurately based on individual components and blending ratios. The non-additive behaviour of TG curves of the blends indicates presence of synergistic effects which could further promote the volatile yields during the co-pyrolysis process. The mixed model including homogeneous reaction model (denoted as HRM) and shrinking core model (denoted as SCM) models were used to predict the variation in kinetic parameters (activation energy and pre-exponential factor) with different blend ratios. The most obvious synergistic effects were observed when the blending ratio was 25 % on account of maximum mass loss rate from the differential thermogravimetry (denoted as DTG), maximum deviation based on root mean square (denoted as RMS) value as well as divergence in the differential thermogravimetric analysis (denoted as DTA) curve.

Download Full-text

Co-Combustion Characteristics of Typical Biomass and Coal Blends by Thermogravimetric Analysis

Frontiers in Energy Research ◽

10.3389/fenrg.2021.753622 ◽

2021 ◽

Vol 9 ◽

Author(s):

Ye Yuan ◽

Yong He ◽

Jiaxin Tan ◽

Yongmeng Wang ◽

Sunel Kumar ◽

...

Keyword(s):

Thermogravimetric Analysis ◽

Loss Rate ◽

Mass Loss Rate ◽

Reaction Model ◽

Combustion Characteristics ◽

Corn Straw ◽

Weight Loss Rate ◽

Exponential Factor ◽

Maximum Mass Loss ◽

Maximum Weight Loss

In this study, the co-combustion characteristics of coal and biomass blends (20, 40, 60, 80, and 100 wt%) were investigated by thermogravimetric analysis. All the samples were operated under an oxidative atmosphere, with a heating rate of 20 C/min. The reaction stages, ignition and burnout temperature, maximum weight loss rate, and different combustion indices were determined. When the percentage of biomass in the blends was increased, the maximum mass loss rate was enhanced in the second region, and the ignition and burnout temperature was lowered, indicating the higher reactivity and better combustion performance of the samples. The comprehensive performance index presented an N shape with the increasing biomass blending ratio. Based on various combustion indices, 20% was an optimum percentage for the co-utilization of coal-biomass blends. A significant promoting interaction was observed between corn straw and rice straw blends, while inhibiting effects occurred between rice husk and coal. The kinetic parameters of the blends were evaluated by the Coats and Redfern method using the nth-order reaction model. The value of activation energy and the pre-exponential factor increased with the decreasing biomass percentage in the blends.

Download Full-text

Isothermal Kinetic Analysis of the Thermal Decomposition of Wood Chips from an Apple Tree

Processes ◽

10.3390/pr9020195 ◽

2021 ◽

Vol 9 (2) ◽

pp. 195

Author(s):

Ivan Vitázek ◽

Martin Šotnar ◽

Stella Hrehová ◽

Kristína Darnadyová ◽

Jan Mareček

Keyword(s):

Thermal Decomposition ◽

Apple Tree ◽

Combustion Process ◽

Reaction Model ◽

Wood Chips ◽

Small Scale ◽

Exponential Factor ◽

Air Atmosphere ◽

First Order Chemical Reaction ◽

Isothermal Kinetic

The thermal decomposition of wood chips from an apple tree is studied in a static air atmosphere under isothermal conditions. Based on the thermogravimetric analysis, the values of the apparent activation energy and pre-exponential factor are 34 ± 3 kJ mol−1 and 391 ± 2 min−1, respectively. These results have also shown that this process can be described by the rate of the first-order chemical reaction. This reaction model is valid only for a temperature range of 250–290 °C, mainly due to the lignin decomposition. The obtained results are used for kinetic prediction, which is compared with the measurement. The results show that the reaction is slower at higher values of degree of conversion, which is caused by the influence of the experimental condition. Nevertheless, the obtained kinetic parameters could be used for the optimization of the combustion process of wood chips in small-scale biomass boilers.

Download Full-text

Bypassing Energy Barriers in Fiber-Polymer Torrefaction

Frontiers in Energy Research ◽

10.3389/fenrg.2021.643371 ◽

2021 ◽

Vol 9 ◽

Author(s):

Zhuo Xu ◽

Shreyas S. Kolapkar ◽

Stas Zinchik ◽

Ezra Bar-Ziv ◽

Lucky Ewurum ◽

...

Keyword(s):

Mass Loss ◽

Synergistic Effects ◽

Mass Loss Rate ◽

Reactive Extrusion ◽

Extrusion Process ◽

Energy Barriers ◽

Natural Energy ◽

Plastic Wastes ◽

The Individual ◽

Blend Ratios

The amount of waste generation has been increasing with a significant amount being landfilled. These non-recyclable wastes contain large number of fiber and plastic wastes which can be treated with thermal processes to turn them into energy sources since they have high calorific values, are abundant and usually tipping fees are paid to handle them. This paper studied the torrefaction of non-recyclable paper (fiber) wastes, mixed plastic wastes (MPW) and their blends at different ratios in the temperature range of 250–400°C through thermogravimetric analysis (TGA). The solid residues after the experiments were analyzed by nuclear magnetic resonance (NMR) spectroscopy. Significant synergy between fiber and MPW were observed at the range 250–300°C, showing both increase in the reaction rate as well as the overall mass loss. At 250°C, the maximum mass loss rate was more than two times higher and the mass loss at the end of the experiments were also much higher compared to the expected results. In addition, synergy was weakened with an increase of temperature, disappearing at 400°C. The existence of such interactions between fiber and plastic wastes indicates that the natural energy barriers during the individual torrefaction in paper waste or plastic waste could be bypassed, and the torrefaction of fiber and plastic blend can be achieved at lower temperatures and/or shorter residence times. The MPW and fiber wastes were also compounded by extrusion (to produce pellets) at 220°C with different blend ratios. The fiber-MPW pellets from extrusion were characterized by IR spectroscopy, rheology, thermal analysis and flexural properties and showed significant chemical changes from the non-extruded blends at the same ratios. From IR characterization, it was found that there was significant increase in hydroxyl (OH) group on account of the carbonyl (C = O) and etheric (C-O-C) groups. The interaction between paper and MPW can be attributed to the plastic polymers acting as a hydrogen donor during the reactive extrusion process. Synergistic effects were also found from mechanical and rheological properties.

Download Full-text

Synergistic effects, gas evolution and ash interaction during isothermal steam co-gasification of biomass with high-sulfur petroleum coke

Energy ◽

10.1016/j.energy.2021.122840 ◽

2022 ◽

Vol 240 ◽

pp. 122840

Author(s):

Xin Yu ◽

Dunxi Yu ◽

Fangqi Liu ◽

Jingkun Han ◽

Jianqun Wu ◽

...

Keyword(s):

Petroleum Coke ◽

Synergistic Effects ◽

Gas Evolution

Download Full-text

Corrosion-wear behavior of 316L stainless steel under different applied potentials

Industrial Lubrication and Tribology ◽

10.1108/ilt-06-2016-0132 ◽

2017 ◽

Vol 69 (2) ◽

pp. 234-240 ◽

Cited By ~ 2

Author(s):

Gaofeng Han ◽

Pengfei Jiang ◽

Jianzhang Wang ◽

Fengyuan Yan

Keyword(s):

Stainless Steel ◽

Mass Loss ◽

316L Stainless Steel ◽

Wear Behavior ◽

Synergistic Effects ◽

Mass Loss Rate ◽

Artificial Seawater ◽

Corrosion Wear ◽

Mechanical Wear ◽

Content Type

Purpose This report aims to study the influence of applied potentials on the corrosion-wear behavior of 316L stainless steel (SS) in artificial seawater. Design/methodology/approach In this study, wear-corrosion behavior of 316L SS had been studied under different applied potentials in artificial seawater by using a reformed pin-on-disc test rig. The applied potentials were selected ranging from –1.2 to 0.3 V (vs Ag/AgCl). The friction coefficient, mass loss rate and current density were determined. Findings It was indicated that mass loss was determined by the combined effect of mechanical wear and chemical corrosion. The wear-corrosion process was synergistic effects dominate while mechanical wear contributed the major material mass loss. Practical implications The results helped us to choose the appropriate metals for application under the specified environment. Originality/value The main originality of this research is to reveal the corrosion-wear behavior of 316L SS under different potentials, which would help us to understand different states of 316L SS under different corrosion environments.

Download Full-text

Kinetic Analysis of the Thermal Degradation of Recycled Acrylonitrile-Butadiene-Styrene by non-Isothermal Thermogravimetry

Polymers ◽

10.3390/polym11020281 ◽

2019 ◽

Vol 11 (2) ◽

pp. 281 ◽

Cited By ~ 2

Author(s):

Rafael Balart ◽

David Garcia-Sanoguera ◽

Luis Quiles-Carrillo ◽

Nestor Montanes ◽

Sergio Torres-Giner

Keyword(s):

Thermal Degradation ◽

Kinetic Analysis ◽

Acrylonitrile Butadiene Styrene ◽

Isoconversional Methods ◽

Reaction Model ◽

Integral Model ◽

Heating Rates ◽

Exponential Factor ◽

Model Free ◽

Butadiene Styrene

This work presents an in-depth kinetic study of the thermal degradation of recycled acrylonitrile-butadiene-styrene (ABS) polymer. Non-isothermal thermogravimetric analysis (TGA) data in nitrogen atmosphere at different heating rates comprised between 2 and 30 K min−1 were used to obtain the apparent activation energy (Ea) of the thermal degradation process of ABS by isoconversional (differential and integral) model-free methods. Among others, the differential Friedman method was used. Regarding integral methods, several methods with different approximations of the temperature integral were used, which gave different accuracies in Ea. In particular, the Flynn-Wall-Ozawa (FWO), the Kissinger-Akahira-Sunose (KAS), and the Starink methods were used. The results obtained by these methods were compared to the Kissinger method based on peak temperature (Tm) measurements at the maximum degradation rate. Combined Kinetic Analysis (CKA) was also carried out by using a modified expression derived from the general Sestak-Berggren equation with excellent results compared with the previous methods. Isoconversional methods revealed negligible variation of Ea with the conversion. Furthermore, the reaction model was assessed by calculating the characteristic and functions and comparing them with some master plots, resulting in a nth order reaction model with n = 1.4950, which allowed calculating the pre-exponential factor (A) of the Arrhenius constant. The results showed that Ea of the thermal degradation of ABS was 163.3 kJ mol−1, while ln A was 27.5410 (A in min−1). The predicted values obtained by integration of the general kinetic expression with the calculated kinetic triplet were in full agreement with the experimental data, thus giving evidence of the accuracy of the obtained kinetic parameters.

Download Full-text

Kinetics, thermodynamics and synergistic effects analyses of petroleum coke and biomass wastes during H2O co-gasification

International Journal of Hydrogen Energy ◽

10.1016/j.ijhydene.2020.06.239 ◽

2020 ◽

Vol 45 (46) ◽

pp. 24502-24517 ◽

Cited By ~ 1

Author(s):

Elbager M.A. Edreis ◽

Xian Li ◽

Abbas H.A. Atya ◽

Swellam W. Sharshir ◽

Ammar H. Elsheikh ◽

...

Keyword(s):

Petroleum Coke ◽

Synergistic Effects

Download Full-text

Co-Pyrolysis Kinetics of Expandable Polystyrene Foam Plastics and Biomass

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.518-523.3295 ◽

2012 ◽

Vol 518-523 ◽

pp. 3295-3301 ◽

Cited By ~ 1

Author(s):

Bao Xia Li ◽

Pen Jin ◽

Shou Kun Cao

Keyword(s):

Synergistic Effects ◽

Reaction Model ◽

Peanut Shell ◽

Polystyrene Foam ◽

Pyrolysis Kinetics ◽

First Order ◽

Expandable Polystyrene ◽

The One ◽

Kinetics Of ◽

Foam Plastics

Based on the thermogravimetric analysis, co-pyrolysis of expandable polystyrene foam plastics (EPS) and three kinds of biomass (bagasse, peanut shell, corncob) were investigated. The result shows that synergistic effects of the co-pyrolysis of EPS/bagasse and EPS/corncob are obvious, but there is no remarkable synergistic effect for the EPS and peanut shell blends. The kinetic analysis indicates that the pyrolysis processes can be described as first order reactions model, a pretty good fitting of experimental data was obtained for all samples. In the EPS and the biomass pyrolysis, respectively， the former can be described as the one first-order reaction model, and the latter can be described as the three consecutive models, while the co-pyrolysis of EPS and biomass needs to be described as the four consecutive models.

Download Full-text

Kinetic Studies on the Thermal Synthesis of Fluorapatite: Model Free and Model-Fitting Methods

Advanced Engineering Forum ◽

10.4028/www.scientific.net/aef.28.75 ◽

2018 ◽

Vol 28 ◽

pp. 75-89

Author(s):

Hamid Reza Javadinejad ◽

Sayed Ahmad Hosseini ◽

Mohsen Saboktakin Rizi ◽

Eiman Aghababaei ◽

Hossein Naseri

Keyword(s):

Activation Energy ◽

Model Fitting ◽

Kinetic Studies ◽

Isoconversional Methods ◽

Reaction Model ◽

Heating Rates ◽

Thermal Synthesis ◽

Exponential Factor ◽

Model Free ◽

Master Plots

The kinetic study for the synthesis of Fluorapatite has been done using the thermogravimetric technique under non-isothermal conditions and at four heating rates of 5, 10, 15 and 20 °C. Both model free and model-fitting methods were used to investigate kinetic parameters. Calcium oxide, phosphorus pentoxide and calcium fluoride were used as the precursor materials. The activation energy values were calculated through model-fitting and isoconversional methods and were used to predict the reaction model and pre-exponential factor. In this case several techniques were considered such as master plots and compensation effects. The results indicated that the reaction mechanism was chemically controlled with second and third order reaction models in the whole range of conversion which the activation energy varied from 25 to 43 kJ/mol.

Download Full-text

Kajian Dehidroksilasi Termal Kaolin menjadi Metakaolin menggunakan Analisis Termogravimetri

ALCHEMY Jurnal Penelitian Kimia ◽

10.20961/alchemy.17.1.47337.105-112 ◽

2021 ◽

Vol 17 (1) ◽

pp. 105

Author(s):

Aprilina Purbasari ◽

Tjokorde Walmiki Samadhi

Keyword(s):

Fourier Transform ◽

Thermogravimetric Analysis ◽

Fourier Transform Infrared ◽

Reaction Model ◽

Order Reaction ◽

X Ray Diffraction ◽

Exponential Factor ◽

X Ray ◽

First Order ◽

Air Atmosphere

Kaolin merupakan mineral yang banyak dimanfaatkan di berbagai industri. Kaolin dapat diubah menjadi metakaolin yang lebih reaktif melalui proses dehidroksilasi termal. Pada penelitian ini, proses dehidroksilasi termal kaolin dari Bangka Belitung menjadi metakaolin dikaji menggunakan analisis termogravimetri pada rentang suhu 30 – 900 °C dengan laju pemanasan 10 °C/menit dalam lingkungan atmosfer udara. Kaolin mengalami empat tahap dekomposisi dan dehidroksilasi kaolin menjadi metakaolin terjadi pada suhu sekitar 450 – 600 °C. Berdasarkan metode Coats dan Redfern, dehidroksilasi kaolin mengikuti model reaksi order satu dengan energi aktivasi 271,66 kJ/mol dan faktor pre-eksponensial 6,13×1015 s-1. Hasil analisis menggunakan spektroskopi X-ray diffraction (XRD) dan Fourier Transform Infrared (FTIR) pada kaolin setelah dipanaskan pada suhu 550 °C selama 3 jam menunjukkan bahwa sebagian besar kaolin telah berubah menjadi metakaolin.Study of Thermal Dehydroxylation of Kaolin to Metakaolin using Thermogravimetric Analysis. Kaolin is a mineral that is widely used in various industries. Kaolin can be converted into metakaolin which is more reactive through thermal dehydroxylation processes. In this study, thermal dehydroxylation process of Bangka Belitung kaolin into metakaolin was studied using thermogravimetric analysis in a temperature range of 30 – 900 °C with a heating rate of 10 oC/min in an air atmosphere condition. Kaolin underwent four stages of decomposition and dehydroxylation of kaolin into metakaolin occured at temperatures around 450 – 600 °C. Based on the Coats and Redfern method, kaolin dehydroxylation followed first order reaction model with activation energy of 271.66 kJ/mol and pre-exponential factor of 6.13×1015 s-1. The analysis using X-ray diffraction (XRD) dan Fourier Transform Infrared (FTIR) spectroscopy on kaolin after heating at temperature of 550 °C for 3 hours showed that most of the kaolin had turned into metakaolin.

Download Full-text