Kinetic studies of pyrolysis and combustion of Thar coal by thermogravimetry and chemometric data analysis
基于热量与化学计量数据分析法的Thar煤热解与燃烧动力学研究
Journal of Thermal Analysis and Calorimetry,July 2012, Volume 109, Issue 1, pp 97-103
Abstract: The concept of weighted mean activation energy has been used to assess the reactivity of Thar coal in terms of pyrolytic and combustion behavior using non-isothermal thermogravimetry. The samples were characterized as low sulfur and high volatile lignite to subbituminous coal. Modified Coats–Redfern method was applied to analyze the kinetic data of both processes. Thermal degradation of the samples studied was explained by three independent first-order kinetic steps. The good correlation coefficients for the independent first-order reaction models show the complexity of the overall process. The activation energy for pyrolysis reaction ranges from 19.20–63.55 to 23.68–54.49 kJ mol−1 for combustion profile. The samples of different rank were classified applying chemometric approach on the reactivity parameters. Principal component analysis was found as a statistical tool to organize the coal samples in accordance to ASTM classification. This study broadens the scope of thermal analysis in the field of coal utilization by assessing coal reactivity.
Pyrolysis kinetics and chemical composition of Hazro coal according to the particle size
基于粒径大小的Hazro煤热解动力学与化学成分研究
Journal of Thermal Analysis and Calorimetry, July 2005, Volume 81, Issue 2, pp 395-398
Summary: The relationship between particle size and chemical composition of Hazro coal (origin: SE Anatolia, Turkey) has been examined by elemental analysis and by thermogravimetric pyrolysis. The chemical composition of the coal was determined by grinding sample particles physically and separating according to their size in mm by sieving. Particle size distribution of the coal and chemical composition of these fractions were given. The coal has been non-isothermally pyrolyzed in a thermogravimetric analyzer to determine the kinetic factors. Thermal gravimetric (TG/DTG) experiments were performed from ambient temperature to 800°C under a nitrogen atmosphere at heating rate 10 K min-1 with five different particle size ranges. Kinetic parameters of the samples were determined using a Coats and Redfern kinetic model, assuming a first-order reaction. Depending on the particle size of the coal samples, the mean activation energy values varied between 49.1 and 84.6 kJ mol-1. The results discussed indicate that activation energies increase as the particle size decreases.
Temperature-controlled combustion and kinetics of different rank coal samples
不同煤样的温控燃烧与动力学
Journal of Thermal Analysis and Calorimetry, January 2005, Volume 79, Issue 1, pp 175-180
Abstract: Differential scanning calorimetry (DSC) and thermogravimetry (TG/DTG) has been used to obtain information on the temperature-controlled combustion characteristics of seventeen coals of different origin from Thrace basin of Turkey. Experiments were performed in air atmosphere up to 600°C at a heating rate of 10°C min-1. The DSC/TG curves clearly demonstrate distinct transitional stages in the entire coal samples studied. Reaction intervals, peak and burn-out temperatures of the coal samples are also determined. Two different kinetic methods known as, Arrhenius and Coats-Redfern, were used to analyze the kinetic data and the results are discussed.
Mechanisms and Kinetics of Pollutant Formation during Reaction of Pulverized Coal
粉煤反应过程中污染物形成机理与动力学
Pulverized-Coal Combustion and Gasification, pp 183-215
Abstract: Pollutants arising from the reaction of pulverized coal can be divided into two classifications. The first classification includes pollutants common to all industrial combustion systems: CO, UHC (unburned hydrocarbons), soot, and NO x due to the fixation of atmospheric N2. The second classification includes pollutants formed from the impurities in coal. Sulfurous and nitrogenous pollutant gases and flyash dominate this classification. Other pollutant impurities are chlorine, fluorine, and traces of toxic metals.
Combustion and pyrolysis characteristics of tunçblek lignite
Tunçblek褐煤燃烧与热解特性
Journal of Thermal Analysis and Calorimetry, March 2006, Volume 83, Issue 3, pp 721-726
Abstract: In this study, thermal characteristics and kinetic parameters of cleaned Tunçbilek lignite were determined by using a Setaram Labsys DTA/TG/DSC thermal analysis system both for combustion and pyrolysis reactions. Experiments were performed at a heating rate of 10°C min–1 under reactive (air) and inert (nitrogen) gases up to 1000°C. Non-isothermal heating conditions were applied and reaction intervals were determined for combustion and pyrolysis reactions from obtained curves. The combustion properties were evaluation by considering the burning profile of the lignite sample. Burning temperatures and rate of combustion were determined from TG/DTG curves. Calorific value of the lignite sample was measured by DSC curve and compared with the adiabatic bomb calorimeter result.
In addition to investigation of the combustion properties, pyrolysis characteristics of the lignite sample were investigated based on TG/DTG/DSC curves. Activation energy (E) and pre-exponential factor (A) were calculated from the TG data by using a Coats–Redfern kinetic model both for combustion and pyrolysis reactions of cleaned Tunçbilek lignite.
Thermal Analysis Applications In Fossil Fuel Science. Literature survey
热分析在化石燃料学科中的应用：文献综述
Journal of Thermal Analysis and Calorimetry, June 2002, Volume 68, Issue 3, pp 1061-1077
Abstract: In this study, instances where thermal analysis techniques (differential scanning calorimetry, thermogravimetry, differential thermal analysis, etc.) have been applied for fossil fuel characterisation and kinetics are reviewed. The scientific results presented clearly showed that thermal analysis is a well-established technique used in fossil fuel research area. The literature survey showed that thermal methods were important not only theoretically but also from a practical point of view.
Recent developments in the application of thermal analysis techniques in fossil fuels
热分析技术在化石燃料研究中的应用进展
Journal of Thermal Analysis and Calorimetry, March 2008, Volume 91, Issue 3, pp 763-773
Abstract: In this review, application of thermal analysis techniques (differential scanning calorimetry, thermogravimetry, differential thermal analysis, etc.) for fossil fuel characterization and kinetics are reviewed between 2001 and 2006. The results presented clearly showed that thermal analysis applications are well-established techniques used in fossil fuel research area.
