Performance evaluation of a flexible CO2-ORC and sorbent regeneration integrated novel dry gasification oxy-combustion power cycle for in-situ sulphur capture, CO2 capture and power generation

Abstract

In this work, CO2-Organic Rankine Cycle (CO2-ORC) and sorbent regeneration integrated novel Dry Gasification Oxy-Combustion (DGOC) power cycle has been proposed. Integration of CO2-ORC, a low-temperature heat recovery cycle, further enhances the power cycle efficiency. This work presents the performance evaluation of proposed cycle in terms of optimum conditions of gasifier and regenerator, sulphur capture efficiency, quality of CO2 capture, net plant efficiency, exergy efficiency and economic aspect with different sorbents for in-situ sulphur capture at various operating pressures in the Aspen Plus simulation environment. Results show that optimum gasifier temperature increase with increase in operating pressure and trend is almost similar for all sorbents studied. Optimum regenerator conditions vary significantly with different sorbent and operating pressure. Maximum efficiency was obtained with CuO sorbent of about 39.85%. CuO has the maximum sulphur capture efficiency of 99.98% whereas Fe2O3 has the lowest Sulphur capture efficiency. Exergy analysis shows a similar trend, with CuO having the maximum exergetic efficiency. Economically combined cycle with MnO sorbent performs marginally better than other sorbents.