Gas chromatographic-mass spectrometric study of the oil fractions produced by microwave-assisted pyrolysis of different sewage sludges.

The pyrolysis of sewage sludge was studied in a microwave oven using graphite as microwave absorber. The pyrolysis temperature ranged from 800 to 1000 degrees C depending on the type of sewage sludge. A conventional electrical furnace was also employed in order to compare the results obtained with both methods. The pyrolysis oils were trapped in a series of condensers and their characteristics such as elemental analysis and calorific value were determined and compared with those of the initial sludge. The oil composition was analyzed by GC-MS. The oils from the microwave oven had n-alkanes and 1-alkenes, aromatic compounds, ranging from benzene derivatives to polycyclic aromatic hydrocarbons (PAHs), nitrogenated compounds, long chain aliphatic carboxylic acids, ketones and esters and also monoterpenes and steroids. The oil from the electric oven was composed basically of PAHs such as naphthalene, acenapthylene, phenanthrene, fluoranthene, benzo[a]anthracene, benzofluoranthenes, benzopyrenes, indenepyrene, benzo[ghi]perylene, and anthanthrene. In contrast, these compounds were not produced in the case of microwave-assisted pyrolysis.

[1]  J. J. Pis,et al.  Modification of the surface chemistry of active carbons by means of microwave-induced treatments , 1999 .

[2]  Paul T. Williams,et al.  Composition of oils derived from the batch pyrolysis of tyres , 1998 .

[3]  I C T Silveira,et al.  Low temperature conversion of sludge and shavings from leather industry. , 2002, Water science and technology : a journal of the International Association on Water Pollution Research.

[4]  Lilly Shen,et al.  An experimental study of oil recovery from sewage sludge by low-temperature pyrolysis in a fluidised-bed , 2003 .

[5]  Paul T. Williams,et al.  Influence of temperature on the products from the flash pyrolysis of biomass , 1996 .

[6]  Paul T. Williams,et al.  Polycyclic aromatic hydrocarbons in waste derived pyrolytic oils , 1994 .

[7]  W. McWhinnie,et al.  Rapid microwave pyrolysis of coal: Methodology and examination of the residual and volatile phases , 1995 .

[8]  Anthony V. Bridgwater,et al.  Research in thermochemical biomass conversion. , 1988 .

[9]  K. E. Harfi.  Pyrolysis of the Moroccan (Tarfaya) oil shales under microwave irradiation , 2000 .

[10]  S. Jeyaseelan,et al.  Development of adsorbent/catalyst from municipal wastewater sludge , 1996 .

[11]  A. Bridgwater,et al.  An overview of fast pyrolysis of biomass , 1999 .

[12]  Thomas Nussbaumer,et al.  Mechanisms and kinetics of homogeneous secondary reactions of tar from continuous pyrolysis of wood chips , 2002 .

[13]  Juan A. Conesa,et al.  Evolution of gases in the primary pyrolysis of different sewage sludges , 1998 .

[14]  J. J. Pis,et al.  Microwave-induced pyrolysis of sewage sludge. , 2002, Water research.

[15]  William Y. Svrcek,et al.  Ultrapyrolysis of n-hexadecane in a novel micro-reactor , 1990 .

[16]  J. Werther,et al.  Sewage sludge combustion , 1999 .

[17]  M. Lallemant,et al.  Pyrolysis of Timahdit, Morocco, oil shales under microwave field , 1994 .

[18]  M. Diez,et al.  Hydrogen donor and acceptor abilities of pitches from coal and petroleum evaluated by gas chromatography 1 Paper presented at the 1998 Spanish International Meeting, Lugo, Spain, 6–8 July 1998. 1 , 1999 .

[19]  J. A. Menéndez,et al.  On the pyrolysis of sewage sludge: the influence of pyrolysis conditions on solid, liquid and gas fractions , 2002 .

[20]  G. Lu,et al.  Surface area development of sewage sludge during pyrolysis , 1995 .

[21]  B. Krieger-Brockett.  Microwave pyrolysis of biomass , 1994 .

[22]  J. J. Pis,et al.  Thermal Treatment of Active Carbons: a Comparison Between Microwave and Electrical Hating , 1999 .