A Sectional Approach for the Entrained-Flow Gasification of Slurry Fuels

Abstract

Energy densification is the overall objective of the on-going bioliq project. Bioslurry, obtained via fast pyrolysis of low-grade biogenic resources, is converted into high quality syngas in a high pressure entrained flow gasifier. The modeling of this three-phase system involving high pressure and high temperature sub-processes is very challenging. The detailed representation of the chemical sub-processes goes along with an increase of the computational cost. In this work, a novel approach is developed to achieve fast and accurate Computational Fluid Dynamics (CFD) simulations of the gasification of a slurry fuel in a laboratory entrained flow gasifier under atmospheric pressure. The method investigated relies on a sectional approach to describe the char gasification. An Euler-Euler approach is used for the modeling of the slurry/gas phase system. Ethylene glycol is used to represent the liquid part of the slurry. Experimental

Parametrization of a Sectional Approach for the Entrained-Flow Gasification of Biomass Char

“…The bases for the current approaches were first presented in Fradet et al 2018 . This subsection aims at outlining the general modeling concept and the improvements achieved.…”

“…Finally, the heat exchange was modeled by the Ranz–Marshall correlation, and the latent heat from the ethylene glycol evaporation was also considered. Only a brief overview of the modeling of the liquid conversion is given here; for more details, the readers are referred to Fradet et al 2020 …”

“…Another approach consists in following the solid particles' distribution and describing their conversion with transport equations. In this context, a sectional approach 34 was successfully applied for one slurry test case. The variables of interest for the solid particles are calculated on the CFD mesh rather than with the help of individual numerical points.…”

Optimization of Slag Mobility of Biomass Fuels in a Pilot‐scale Entrained‐Flow Gasifier

“…The bioSyncrude® is used as feedstock for the pressurized entrained‐flow gasifier in the next step of the process chain to gain a tar‐free and low‐methane syngas 4–7. At high temperatures of > 1200 °C and pressures of 40–80 bar, the ash of the slurry melts and forms a slag layer, which flows down the inner reactor wall.…”

Chemical fractionation of inorganic constituents in entrained flow gasification of slurry from straw pyrolysis

“…In the gasifier temperatures over 1200 • C and pressures of 40-80 bars are dominant. The resulting tar-free and low methane syngas is used as the basic reactant for synthetic biofuels and chemicals [4][5][6]. The high temperatures cause the ash constituents of the slurry to melt.…”