Biomass integrated gasification combined cogeneration with or without CO_2 capture - A comparative thermodynamic study

摘要

Fossil fuels presently cater to majority of energy demand of the world. However, due to the climate change problem capture of CO_2 emitted from the use of fossil fuels is emerging as a necessity. Alternately, developing technology with CO_2 neutral fuels may reduce green house gas emission. Possible even better solution may be combining both of these options, i.e., employing CO_2 capture process for energy efficient system using CO_2 neutral fuels, say biomass. In this paper, such cogeneration system with CO_2 capture using amine solution has been proposed. Thermodynamic modeling for the detail process has been implemented using ASPEN Plus~®. Comparative study of performance relative to a similar base case plant without carbon capture has been presented. Results show post combustion CO_2 capture process is better than pre-combustion CO_2 capture process for such plants with net negative CO_2 emission. Also degree of CO_2 capture has to be optimized on the basis of the overall performance of the plant as higher CO_2 capture affects thermodynamic and economic performance of the plant, specifically beyond certain value. In a net CO_2 negative emission plant extent of CO_2 capture is quite flexible and may be decided for optimum performance.