Master's thesis analytically analyses influence of equivalence ratio and oxygen content in oxygen-enriched air in biomass gasification on the composition of product gas, temperature, efficiency of gasification, amount, and lower heating value of the product gas. The analysis is performed using an equilibrium non-stoichiometric model created in Python, where chemical equilibrium was calculated using the open-source module Reaktoro. Results of the analysis show that the highest volume fractions of combustible components in the product gas are achieved with a 95 % oxygen content in the enriched air. At the same oxygen content and equivalence ratio of 0.26, highest gasification efficiency (87.5 %) and lower heating value of the product gas (13.8 MJ/kg) are also achieved. Taking into account energy consumption for air separation, highest efficiency decreases to 85.7 % and is achieved at 58 % oxygen content, and lower heating value is 11.8 MJ/kg. The analysis also showed that when modelling the composition of the product gas, it is necessary to correctly assume the proportion of solid carbon residue. The assumption of a constant 5 % residue fraction in the entire analysed area overestimates the volume fractions of CH4 and consequently the efficiency and heating value of the product gas in areas of low air ratios.
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