Experimental Research on Catalytic Combustion Characteristics of Inferior Coal and Sludge Mixture

2017 ◽  
Vol 140 (3) ◽  
Author(s):  
Yunfei Yan ◽  
Shuai Feng ◽  
Li Zhang ◽  
Lixian Li ◽  
Lei Zhang ◽  
...  
Keyword(s):  
Activation Energy ◽  
Thermogravimetric Analysis ◽  
Metal Oxides ◽  
Apparent Activation Energy ◽  
Combustion Characteristics ◽  
Combustion Dynamics ◽  
Weight Losses ◽  
Coal Sludge ◽  
Lower Temperature ◽  
Catalytic Effects

Catalytic effects of metal oxides on combustion characteristics of inferior coal, sludge, and their mixture were investigated by thermogravimetric analysis. Combustion and thermal dynamic characteristics including ignition temperatures, apparent activation energy, and frequency factors of inferior coal, sludge, and their mixture were observed. The catalytic effects and mechanism of combustion were discussed. Results showed that thermal gravity analysis (TG) and derivative thermogravimetric analysis (DTG) curves of coal and sludge shifted to lower temperature side, the weight losses increased, and the ignition performance was improved with the addition of metal oxides CaO, Al2O3, and K2O. The combustion dynamics analysis showed that the apparent activation energy of cocombustion of coal blending sludge decreased by 11–20% and the frequency factors increased by 20–30%. The minimum apparent activation energy and the maximum frequency factors were obtained in the presence of K2O, indicating that the catalytic effect of K2O was most significant.

Deep oxidation of 1,2-dichlorobenzene over Ti-doped iron oxide

2014 ◽  
Vol 16 (25) ◽  
pp. 12731-12740 ◽  
Author(s):  
Xiaodong Ma ◽  
Xueyue Suo ◽  
Huiqin Cao ◽  
Jie Guo ◽  
Lu Lv ◽  
...  
Keyword(s):  
Activation Energy ◽  
Iron Oxide ◽  
Apparent Activation Energy ◽  
Iron Oxides ◽  
Deep Oxidation ◽  
Lower Temperature

1,2-Dichlorobenzene was completely oxidized to CO2, H2O and HCl over Ti-doped iron oxides at lower temperature with lower apparent activation energy.

Pyrolysis Kinetics and Characteristics of Wood-Based Materials from Municipal Solid Waste

2014 ◽  
Vol 960-961 ◽  
pp. 442-446
Author(s):  
Lin Chen ◽  
Shu Zhong Wang ◽  
Zhi Qiang Wu ◽  
Hai Yu Meng ◽  
Jun Zhao
Keyword(s):  
Activation Energy ◽  
Thermogravimetric Analysis ◽  
Municipal Solid Waste ◽  
Apparent Activation Energy ◽  
Solid Waste ◽  
Heating Rate ◽  
Pyrolysis Kinetics ◽  
Kinetics Analysis ◽  
Exponential Factor ◽  
Pyrolysis Characteristics

Wood-based materials from Municipal Solid Waste have the potential of covering a significant part of the future demand on gasification capacities. However, their pyrolysis kinetics and gasification behavior has not yet been fully investigated. This paper describes the pyrolysis characteristics of typing paper and Chinese parasol from municipal solid waste applying the non-isothermal thermogravimetric analysis, the apparent activation energy and the pre-exponential factor were obtained by kinetics analysis at the heating rate of 10/20/40 oC•min-1.

Study on Co-Combustion Characteristics of Coals under Pure Oxygen Atmosphere

2011 ◽  
Vol 361-363 ◽  
pp. 882-886
Author(s):  
Ming Yan Gu ◽  
Xu Hui Liu ◽  
Biao Ma ◽  
Jia Xin Li
Keyword(s):  
Activation Energy ◽  
Bituminous Coal ◽  
Volatile Matter ◽  
Combustion Characteristics ◽  
Pure Oxygen ◽  
Burning Process ◽  
Coal Burning ◽  
Air Atmosphere ◽  
Anthracite Coal ◽  
Lower Temperature

In this study, the combustion behaviors of three kinds of coal and their mixtures under the pure oxygen and air atmosphere were studied by using a thermo-gravimetric analyzer. The combustion characteristics such as ignition and burnout behavior were investigated in the temperature from 20°C to 800°C. The influence of mixing Shenhua coal with Huaibei bituminous and Sanming anthracite coal on combustion characteristics was conduced. The results obtained show that pure oxygen content accelerated the coal burning process greatly; the coal volatile matter started to release at a lower temperature and the coal burning process was finished earlier compared with the burning process under the air atmosphere. The addition of Shenhua coal improved the combustion characteristics of both Huaibei bituminous coal and Sanming anthracite in a different way. For the Huaibei bituminous coal, both the ignition and burnout temperature decreased linearly with the increasing ratio of Shenhua coal; while for the Sanming anthracite, the addition of Shenhua coal greatly lowered the mixture ignition temperature, and the burnout temperature was nearly the same. The activation energy of the mixture coal with Shenhua and Huaibei coal reduced with the ratio of Shenhua coal. For the Shenhua and Sanming coal mixture, the activation energy changed differently at the two burning stages.

scholarly journals Decomposition Characteristics and Kinetics of Microalgae in N2 and CO2 Atmospheres by a Thermogravimetry

2017 ◽  
Vol 2017 ◽  
pp. 1-7 ◽  
Author(s):  
Xu Qing ◽  
Ma Xiaoqian ◽  
Yu Zhaosheng ◽  
Cai Zilin ◽  
Ling Changming
Keyword(s):  
Activation Energy ◽  
Thermogravimetric Analysis ◽  
Thermal Degradation ◽  
Apparent Activation Energy ◽  
Kinetic Parameters ◽  
Reaction Order ◽  
Heating Rates ◽  
Residual Mass ◽  
Second Stage ◽  
Kinetics Of

The thermal degradation characteristics of microalgae were investigated in highly purified N2 and CO2 atmospheres by a thermogravimetric analysis (TGA) under different heating rates (10, 20, and 40°C/min). The results indicated that the total residual mass in CO2 atmosphere (16.86%) was less than in N2 atmosphere (23.12%); in addition, the kinetics of microalgae in N2 and CO2 atmospheres could be described by the pseudo bicomponent separated state model (PBSM) and pseudo-multi-component overall model (PMOM), respectively. The kinetic parameters calculated by Coats-Redfern method showed that, in CO2 atmosphere, the apparent activation energy (E) of microalgae was between 9.863 and 309.381 kJ mol−1 and the reaction order (n) was varied from 1.1 to 7. The kinetic parameters (E,n) of the second stage in CO2 atmosphere were quite similar to those in N2 atmosphere.

scholarly journals Effect of KMnO4 on catalytic combustion performance of semi-coke

2020 ◽  
Vol 9 (1) ◽  
pp. 559-566
Author(s):  
Luyao Kou ◽  
Junjing Tang ◽  
Tu Hu ◽  
Baocheng Zhou ◽  
Li Yang
Keyword(s):  
Activation Energy ◽  
Thermogravimetric Analysis ◽  
Apparent Activation Energy ◽  
Ignition Temperature ◽  
Catalytic Combustion ◽  
Integration Method ◽  
Kinetic Behavior ◽  
Conversion Rates ◽  
Coke Combustion ◽  
Addition Amount

AbstractThe effect of KMnO4 on the combustion characteristics and kinetic behavior of semi-coke was studied by thermogravimetric analysis. When 6 wt% KMnO4 was added, the ignition temperature of semi-coke was the lowest. The apparent activation energy of semi-coke with different addition amount of KMnO4 was calculated by Coats–Redfern integration method, the apparent activation energy of semi-coke during combustion reaction first decreased and then increased with increase in KMnO4. When 6 wt% KMnO4 is added, the apparent activation energy is minimal. The apparent activation energy of semi-coke with 2 wt% KMnO4 added at different conversion rates was calculated using Flynn–Wall–Ozawa integration method. The results show that the apparent activation energy of semi-coke combustion decreases with the increase of conversion.

scholarly journals The Hydrothermal Stability and the Properties of Non- and Strongly-Interacting Rh Species over Rh/γ, θ-Al2O3 Catalysts

Catalysts ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 99
Author(s):  
Guanghao Cheng ◽  
Gurong Shen ◽  
Jun Wang ◽  
Yunhao Wang ◽  
Weibo Zhang ◽  
...  
Keyword(s):  
Activation Energy ◽  
Apparent Activation Energy ◽  
Aging Time ◽  
Reaction Path ◽  
Aging Treatment ◽  
Hydrothermal Stability ◽  
Hydrothermal Aging ◽  
Strongly Interacting

The present work reports the effects of γ-, θ-phase of alumina on the hydrothermal stability and the properties of non- and strongly-interacting Rh species of the Rh/Al2O3 catalysts. Comparing to γ-Al2O3, θ-Al2O3 can not only reduce the amount of occluded Rh but also better stabilize Rh during hydrothermal aging treatment. When the aging time was prolonged to 70 h, all the non-interacting Rh was transformed into strongly-interacting Rh and occluded Rh. The XPS results indicated that non- and strongly-interacting Rh might exist in the form of Rh/Rh3+ and Rh4+, respectively. CO-NO reaction was chosen as a probe reaction to research more information about non- and strongly-interacting Rh. The two Rh species had similar apparent activation energy (Eapp) of 170 kJ/mol, which indicated that non- and strongly-interacting Rh follow the same reaction path. The non-interacting Rh was removed from aged samples by the acid-treated method, and obtained results showed that only 2.5% and 4.0% non-interacting Rh was maintained in aged Rh/γ-Al2O3 and Rh/θ-Al2O3.

The activation energy U(T,B) in high temperature superconductor

2020 ◽  
Vol 92 (2) ◽  
pp. 20601
Author(s):  
Abdelaziz Labrag ◽  
Mustapha Bghour ◽  
Ahmed Abou El Hassan ◽  
Habiba El Hamidi ◽  
Ahmed Taoufik ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Activation Energy ◽  
Phase Diagram ◽  
High Temperature ◽  
Apparent Activation Energy ◽  
High Temperature Superconductor ◽  
Flux Flow ◽  
Resistivity Measurements ◽  
Vortex Phase ◽  
The Magnetic Field

It is reported in this paper on the thermally assisted flux flow in epitaxial YBa2Cu3O7-δ deposited by Laser ablation method on the SrTiO3 substrate. The resistivity measurements ρ (T, B) of the sample under various values of the magnetic field up to 14T in directions B∥ab-plane and B∥c-axis with a dc weak transport current density were investigated in order to determine the activation energy and then understand the vortex dynamic phenomena and therefore deduce the vortex phase diagram of this material. The apparent activation energy U0 (B) calculated using an Arrhenius relation. The measured results of the resistivity were then adjusted to the modified thermally assisted flux flow model in order to account for the temperature-field dependence of the activation energy U (T, B). The obtained values from the thermally assisted activation energy, exhibit a behavior similar to the one showed with the Arrhenius model, albeit larger than the apparent activation energy with ∼1.5 order on magnitude for both cases of the magnetic field directions. The vortex glass model was also used to obtain the vortex-glass transition temperature from the linear fitting of [d ln ρ/dT ] −1 plots. In the course of this work thanks to the resistivity measurements the upper critical magnetic field Hc2 (T), the irreversibility line Hirr (T) and the crossover field HCrossOver (T) were located. These three parameters allowed us to establish a phase diagram of the studied material where limits of each vortex phase are sketched in order to optimize its applicability as a practical high temperature superconductor used for diverse purposes.

scholarly journals Effect of CaO on catalytic combustion of semi-coke

2021 ◽  
Vol 10 (1) ◽  
pp. 011-020
Author(s):  
Luyao Kou ◽  
Junjing Tang ◽  
Tu Hu ◽  
Baocheng Zhou ◽  
Li Yang
Keyword(s):  
Activation Energy ◽  
Apparent Activation Energy ◽  
Combustion Rate ◽  
Activation Energies ◽  
Combustion Reaction ◽  
Tg Analysis ◽  
Conversion Rates ◽  
Apparent Activation Energies ◽  
Ozawa Integral Method ◽  
Addition Amount

Abstract Generally, adding a certain amount of an additive to pulverized coal can promote its combustion performance. In this paper, the effect of CaO on the combustion characteristics and kinetic behavior of semi-coke was studied by thermogravimetric (TG) analysis. The results show that adding proper amount of CaO can reduce the ignition temperature of semi-coke and increase the combustion rate of semi-coke; with the increase in CaO content, the combustion rate of semi-coke increases first and then decreases, and the results of TG analysis showed that optimal addition amount of CaO is 2 wt%. The apparent activation energy of CaO with different addition amounts of CaO was calculated by Coats–Redfern integration method. The apparent activation energy of semi-coke in the combustion reaction increases first and then decreases with the increase in CaO addition. The apparent activation energies of different samples at different conversion rates were calculated by Flynn–Wall–Ozawa integral method. It was found that the apparent activation energies of semi-coke during combustion reaction decreased with the increase in conversion.

Effect of orienting coatings on the apparent activation energy of boundary film destruction

2007 ◽  
Vol 28 (1) ◽  
pp. 12-18 ◽  
Author(s):  
I. A. Buyanovskii ◽  
Yu. N. Drozdov ◽  
Z. V. Ignatieva ◽  
T. M. Savinova ◽  
V. A. Levchenko ◽  
...  
Keyword(s):  
Activation Energy ◽  
Apparent Activation Energy ◽  
Boundary Film
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