Thermodynamic Comparison of alternative Biomass Gasification Techniques for producing Syngas for Gas Turbine Application

In this paper, Aspen Plus® models of biomass gasification process combined with plasma reactor for tar removal and plasma gasification process were developed respectively, validated and analyzed thermodynamically. The analysis shows that plasma technology is capable of producing syngas with acceptable tar content for gas turbine application. However, this comes with a huge energy penalty. For example, within the context of the analysis carried out in this paper, the thermodynamic efficiency of the biomass gasification process combined with plasma tar cleaning was found to be 43.6% while that of the plasma gasification process was 37.3% despite its higher bio-syngas calorific value. The lower efficiency recorded for the plasma gasification process occurs as a result of the higher electrical energy required to attain the high temperature needed for the gasification of the biomass material. As a result of the low efficiency, plasma tar cleaning of raw bio-syngas or plasma gasification, although technologically feasible, may not be a viable route for producing bio-syngas for gas turbine application. However, it may be a viable option for energy storage if the plasma reactor will be powered with electricity from wind and other renewable energy resources during off peak period.