Model development for biomass gasification in an entrained flow gasifier using intrinsic reaction rate submodel. (15th January 2016)

• Record Type: Journal Article
• Authors: Gao, Xiaoyan; Zhang, Yaning; Li, Bingxi; Yu, Xiangyu
• Is Part Of: Energy conversion and management. Volume 108(2016)
• Page Start: 120
• Page End: 131
• Publication Date: 2016-01-15
• Subjects: Model development -- Intrinsic reaction rate model -- Biomass gasification -- Entrained flow gasifier; Direct energy conversion -- Periodicals; Energy storage -- Periodicals; Energy transfer -- Periodicals; Énergie -- Conversion directe -- Périodiques; Direct energy conversion; Periodicals; 621.3105
• DOI: 10.1016/j.enconman.2015.10.070
• Languages: English
• ISSNs: 0196-8904

Abstract

Highlights: A comprehensive model is developed for biomass entrained flow gasification. Intrinsic reaction rate submodel for biomass char reactions is realized. Effects of diffusion rate and kinetic rate are considered. The relative errors between the simulated and experimental results are reasonable. Abstract: Intrinsic reaction rate submodel is established in this study to consider the effects of diffusion rate and kinetic rate for simulating the char reactions due to their slow reaction rates and important controlling steps. The biomass gasification model for an entrained flow gasifier is developed with the Euler–Lagrange method using ANSYS FLUENT software. Gas phase is treated as continuous phase in standard k – ε model to close governing equations whereas biomass particles are treated as discrete phase in discrete phase model (DPM) to track the movement of particles. For homogeneous phase reactions, finite rate/eddy dissipation model is applied to calculate the reaction rates. For heterogeneous phase reactions, intrinsic reaction rate model is realized by coding the user-defined functions (UDFs) to calculate char reaction rates. The results obtained from this study show that the relative errors of volumetric concentrations are mainly within the range of 1–18% and the relative errors of lower heating value, gas production, cold gas efficiency and carbon conversion efficiency are within the ranges of 1–13%, 1–8%, 1–12% and 1–11%, respectively. The CFD model developed in this study can be used to simulate biomass gasification processes for entrained flow gasifiers.