title: Supercritical water gasification of Eucalyptus grandis and related pyrolysis char: Effect of feedstock composition.
abstract: Eucalyptus grandis (E. grandis) wood and char products derived from pyrolysis of E. grandis wood, were gasified in supercritical water at 450°C - with and without the use of a homogeneous (K2CO3) and heterogeneous (Ni/Al2O3-SiO2) catalyst. Gas yields and gasification efficiencies were measured experimentally and compared to calculated thermodynamic equilibrium values, specifically considering the effects of the O/C ratio and volatile matter content of the feed material. Thermodynamically, feed material with lower O/C ratios (0.22) typically resulted in higher CH4 yields (30mol/kgfeed,dry) and gasification efficiencies (188%). However, experimentally, feed material with lower O/C ratios and lower volatile matter resulted in the lowest CH4 yields and gasification efficiencies. Furthermore, a linear relationship between the carbon efficiency (CE) and both the volatile matter content and O/C ratio of the feed material was found to hold true in both catalytic and non-catalytic experiments.
authors.affiliation: Department of Process Engineering, Stellenbosch University, Private Bag X1, Matieland 7602, South Africa.
authors.forename: Jeanne
authors.initials: J
authors.lastname: Louw
authors.affiliation: Department of Process Engineering, Stellenbosch University, Private Bag X1, Matieland 7602, South Africa.
authors.forename: Cara E
authors.initials: CE
authors.lastname: Schwarz
authors.affiliation: Department of Process Engineering, Stellenbosch University, Private Bag X1, Matieland 7602, South Africa. Electronic address: ajburger@sun.ac.za.
authors.forename: Andries J
authors.initials: AJ
authors.lastname: Burger
mesh_terms: D005052:Eucalyptus / Q000737:chemistry*; D006358:Hot Temperature; D008697:Methane / Q000032:analysis / Q000737:chemistry / Q000378:metabolism; D014867:Water; D014934:Wood / Q000737:chemistry*
chemical_list: D014867:Water; D008697:Methane
keywords: Eucalyptus grandis; Pyrolysis char; Supercritical water gasification (SCWG); Thermodynamic equilibrium yields; Van Krevelen diagram