Entrained flow gasification: Experiments and mathematical modelling based on RANS

Interdisciplinary research has been conducted in the frame of the Helmholtz Virtual Institute for Gasification Technology (HVIGasTech). The main objective is to develop a validated numerical simulation tool for describing the entrained flow gasification of biomass (cf. bioliq process). This paper presents work-in-progress and reports the recent experimental and numerical results for the entrained flow gasification of model fuels (ethylene glycol, 90 % ethylene glycol + 10 % wood-char) under atmospheric conditions. Three experimental campaigns have been carried out at the Research Entrained flow GAsifier (REGA). Radial profiles of gas phase composition ($\text{CH}_4$, $\text{CO}$, $\text{CO}_\text{2}$, $\text{H}_2$) and temperature have been measured at burner distances of 300 mm and 680 mm. In parallel to the experimental campaigns, RANS based simulations have been performed using ANSYS Fluent. Turbulence-chemistry interaction has generally been described by the Eddy Dissipation Concept (EDC). EDC has been used in combination with two global reaction mechanisms for the entrained flow gasification of ethylene glycol: the HVI1 mechanism and the extended Jones-Lindstedt mechanism. ... mehrDevolatilisation and the heterogeneous reactions of wood-char with $\text{CO}_\text{2}$ and $\text{H}_\text{2}\text{O}$ are computed using kinetics derived from measurements. The numerical results for the entrained flow gasification of ethylene glycol show good agreement with the measured data. In particular, the model based on EDC and the HVI1 mechanism predicts the gas composition well. Gas temperatures are slightly overpredicted. The numerical results for the gasification of slurry deviate from the experimental results concerning the gas phase composition. Further research needs to be carried out to close this gap.