Search Results

You are looking at 1 - 10 of 1,166 items for :

  • All content x
Clear All

Abstract  

FTIR spectrometry combined with TG provides information regarding mass changes in a sample and permits qualitative identification of the gases evolved during thermal degradation. Various fuels were studied: coal, peat, wood chips, bark, reed canary grass and municipal solid waste. The gases evolved in a TG analyser were transferred to the FTIR via a heated teflon line. The spectra and thermoanalytical curves indicated that the major gases evolved were carbon dioxide and water, while there were many minor gases, e.g. carbon monoxide, methane, ethane, methanol, ethanol, formic acid, acetic acid and formaldehyde. Separate evolved gas spectra also revealed the release of ammonia from biomasses and peat. Sulphur dioxide and nitric oxide were found in some cases. The evolution of the minor gases and water parallelled the first step in the TG curve. Solid fuels dried at 100C mainly lost water and a little ammonia.

Restricted access

Abstract  

Although thermogravimetric analysis (TG) has become an indispensable tool for the analysis and characterization of materials, its scope is limited as no information is obtained about the qualitative aspects of the evolved gases during the thermal decomposition. For processes involving mass loss, a powerful technique to provide this missing information is Fourier transform infrared spectroscopy (FT-IR) in combination with TG. It supplies a comprehensive understanding of thermal events in a reliable and meaningful way as data are obtained from a single sample under the same conditions. The coupling TG/FT-IR is used in fuel analysis for the identification of residual volatiles, to determine their sequence of release and to resolve thermogravimetric curves. In this work, the usefulness of TG/FT-IR for characterizing middle distillate fuel residues is illustrated with some typical examples of recent application. A Bio-Rad FTS 25 FT-IR spectrometer coupled with a TA Instruments TGA 2950 thermogravimetric analyzer was used for data aquisition. The results obtained demonstrate the utility of this combined technique in determining the decomposition pathway of tarry materials at various stages of pyrolysis, thereby allowing new insights into the complex thermal behaviour of hydrocarbon residual systems.

Restricted access

Waste and fuels from waste

Part I. Analysis of thermal decomposition

Journal of Thermal Analysis and Calorimetry
Authors: Danuta Król and Sławomir Poskrobko

unconventional fuels in generator processes. Much of the waste is a mixture of composite, not suitable for processing recycled material. However, if they have an energetic potential (due to containing chemical energy), then thermal processes stand in the

Restricted access

.B. Coffin 2004 Use of stable carbon isotopes and multivariate statistics to source-apportion fuel hydrocarbons Environmental Research, Engineering and Management 4

Restricted access
Journal of Radioanalytical and Nuclear Chemistry
Authors: G. Timofeev, V. Gabeskiria, G. Simakin, V. Mishenev, A. Bevz, and A. Rykov

Abstract  

As a rule the analysis of nuclear oxide fuel includes the determination of uranium, plutonium, their isotopic composition, cation impurities, carbon, nitrogen, chlorine, fluorine, oxygen coefficient. In this paper we discuss different methods for the a analysis of unirradiated uranium and plutonium oxide fuelds used in the laboratories of the Analytical Chemistry Department: coulometry, emission analysis, chromatography, X-ray analysis. Much consideration is being given to the analysis of uranium and plutonium oxide samples and uranium-plutonium mixed fuels irradiated in the BOR-60 using mass-spectrometric (isotope dilution method) and radiometric techniques. The results of uranium and plutonium determination by these methods are compared. The main analytical characteristics of the methods are given.

Restricted access

References [1] Mekhilef S. , Saidur R. , Safari A. ( 2012 ), Comparative study of different fuel cell technologies . Renewable and

Restricted access

Refuse derived fuels pyrolysis

Influence of process temperature on yield and products composition

Journal of Thermal Analysis and Calorimetry
Authors: S. Casu, S. Galvagno, A. Calabrese, G. Casciaro, M. Martino, A. Russo, and Sabrina Portofino

Summary Refuse derived fuels (RDF) characterization and pyrolysis behaviour, carried out by means of thermogravimetric analysis, infrared and mass spectroscopy, are presented. Thermal degradation of RDF takes place through three main mass loss stages; the analyses of evolved gas allow us to discriminate the contributions of the different fractions (paper, LDPE, wood, rubber, etc.) to the global decomposition. Furthermore thermogravimetry (TG) was used for the determination of kinetic parameters, using the differential method. In order to set up the conditions of production of a good quality pyrolysis gas, the operating conditions of RDF in a pyrolysis reactor have been simulated. Data show that the volatile fraction grows with the temperature, together with the relative conversion, and that light volatile fraction (hydrogen, ethyne, etc.) gets richer, at the expense of superior homologous hydrocarbons.

Restricted access

Abstract  

Fire safety on fuel containers can be improved at its initial stage if flame spreading can be controlled. Therefore, the understanding of the fundamental processes that control flame spreading will help us to determine a few control parameters that could be useful to improve security in fuel deposits. A series of experiments have been conducted in different fuel containers that helped to understand the basic mechanisms involved. A new phenomenon of convection ahead of the flame is observed in liquid fuels that do not appear in solid fuels. Finally, two control factors have been found useful to control fire spread: the initial fuel surface temperature and the convection zone observed in front of the flame. The first experimental results observed controlling these two factors led flame to spreading velocities of order 1 cm s–1 and, in some cases, flame extinguishes.

Restricted access

134 138 Pischinger R. Thermodynamik der Verbrennungskraftmmaschine , Springer, 1989. Zöldy M. Alternative fuels for internal combustion engines

Restricted access

Abstract  

Three bio-fuels with or without additives and their fly ash samples were characterized using simultaneous Thermogravimetry-Differential Thermal Analysis-Fourier Transform Infrared Spectrometry-Mass Spectrometry (TG-DTA-FTIR-MS), X-ray Diffraction (XRD), X-ray Fluorescence (XRF), and Scanning Electron Microscopy-Energy Dispersive Spectrometry (SEM-EDS). The results show that the additives increase the reactivity of the bio-fuel during combustion. The additives also significantly decrease the amount of unburned carbon in the fly ash. The additives affect the compounds formed in the fly ash sample, and consequently the thermal behaviour of the fly ash. The fly ash samples are thermally stable in air up to 100C. The fly ash samples contain fine particles with irregular shape, small round particles, and large hollow spherical particles with entrapped gases.

Restricted access