Solar Assisted Gasification

  • Syed Shabbar Raza

Student thesis: Master's Thesis

Abstract

Gasification is a high temperature thermo-chemical pathway and is used to convert a solid fuel/feedstock into combustible syngas (CO and H2), fuel and chemicals. The gasified species derive their formation energy by burning of 20-30% the feedstock. The combustion resulted in emission of soot, particulate matter, NOx and SOx. Therefore, an attempt is made in this thesis to replace the energy required for gasification by concentrated solar power. This study is conducted by simulating the solar gasification process using thermodynamic modeling and optical/numerical simulation. Initially, the properties of a baseline feedstock, i.e. bituminous coal, are determined by analytically measuring the feedstock's proximate, ultimate composition and calorific value. These properties of coal are then used to establish the thermodynamic models for gasification through Equilibrium Constant Approach and Gibbs Energy Minimization Method. The result of cold gasification efficiency for air gasification, air-steam gasification and solar-steam gasification are calculated to be 70%, 71% and 90%, respectively. The heat energy required in the thermodynamic model for solar gasification is then used to design an optical arrangement. That consists of a parabolic and hyperbolic reflector using Cassegrain configuration to concentrate 5 kW of solar flux for the gasifier. Finally, a high fidelity computational fluid dynamics (CFD) simulation is established based on the results of thermodynamic and optical models. The CFD simulation couples the effect of heat transfer through solar radiation and reaction kinetics in the participating media. The result shows cold gasification efficiency of 90% with the product mole fraction of CO and H2, i.e. 0.1 and 0.16, respectively.
Date of Award2011
Original languageAmerican English
SupervisorIsam Janajreh (Supervisor)

Keywords

  • Solar Atmosphere
  • Solar Activity

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