Home  About us  Contact
 

Water Gasification (water + gasification)

Distribution by Scientific Domains
Chemistry75%

Kinds of Water Gasification

  • supercritical water gasification
    		•

    Selected Abstracts

    Kinetic model for noncatalytic supercritical water gasification of cellulose and lignin

    AICHE JOURNAL, Issue 9 2010
    Fernando L. P. Resende
    Abstract This article reports the first kinetics model for Supercritical Water Gasification (SCWG) that describes the formation and interconversion of individual gaseous species. The model comprises 11 reactions, and it uses a lumping scheme to handle the large number of intermediate compounds. We determined numerical values for the rate constants in the model by fitting it to experimental data previously reported for SCWG of cellulose and lignin. We validated the model by showing that it accurately predicts gas yields at biomass loadings and water densities not used in the parameter estimation. Sensitivity analysis and reaction rate analysis indicate that steam-reforming and water,gas shift are the main sources of H2 in SCWG, and intermediate species are the main sources of CO, CO2, and CH4. © 2010 American Institute of Chemical Engineers AIChE J, 2010 [source]

    Exergetic efficiency and options for improving sewage sludge gasification in supercritical water

    INTERNATIONAL JOURNAL OF ENERGY RESEARCH, Issue 4 2007
    Edgar Gasafi
    Abstract The present article deals with an exergy analysis of a process under development for the gasification of biomass in supercritical water (supercritical water gasification, SCWG). This process is aimed at generating hydrogen out of the biogenic feedstock sewage sludge. The principle of the process is based on making use of the modifications of specific physical and chemical properties of water above the critical point (T=374°C, p=221 bar). These properties allow for a nearly complete conversion of the organic substance contained in the feed material into energy-rich fuel gases, containing hydrogen, carbon dioxide and methane. Based on a steady-state model of the process, exergy flow rates are calculated for all components and a detailed exergy analysis is performed. From the exergetic variables, options to improve the individual plant components as well as the overall plant are derived. The components with the highest proportion of exergy destruction in the complete process are identified and possibilities of improving them and the complete system in order to increase the overall efficiency are demonstrated. The combustion chamber necessary for heat supply is found to be the component with the highest proportion of exergy destruction of the complete plant. Moreover, the components of air preheater, reactor contribute significantly to the exergy destruction of the complete system. Copyright © 2006 John Wiley & Sons, Ltd. [source]

    Kinetic model for noncatalytic supercritical water gasification of cellulose and lignin

    AICHE JOURNAL, Issue 9 2010
    Fernando L. P. Resende
    Abstract This article reports the first kinetics model for Supercritical Water Gasification (SCWG) that describes the formation and interconversion of individual gaseous species. The model comprises 11 reactions, and it uses a lumping scheme to handle the large number of intermediate compounds. We determined numerical values for the rate constants in the model by fitting it to experimental data previously reported for SCWG of cellulose and lignin. We validated the model by showing that it accurately predicts gas yields at biomass loadings and water densities not used in the parameter estimation. Sensitivity analysis and reaction rate analysis indicate that steam-reforming and water,gas shift are the main sources of H2 in SCWG, and intermediate species are the main sources of CO, CO2, and CH4. © 2010 American Institute of Chemical Engineers AIChE J, 2010 [source]

    Erratum: Supercritical water gasification.

    BIOFUELS, BIOPRODUCTS AND BIOREFINING, Issue 2 2010
    Andrea Kruse.
    The original article to which this Erratum refers was published in Biofuels, Bioproducts and Biorefining, 2009, 2:415,437 [source]