Evaluation of performance improvement of the combined biomass gasifier power cycle using low-temperature bottoming cycles: organic Rankine cycle, Kalina and Goswami

A novel combination of a conventional combined power plant and low-temperature power generators as a cogeneration cycle coupled with a biomass gasifier is presented in this study. For this purpose, mathematical modeling of organic Rankine cycle (ORC), Kalina, and Goswami cycles was performed as a bottoming power system. To achieve the goals of sustainable energy development, a portion of the fuel required for the proposed cycle has been provided using renewable biomass fuels. The results indicated that the base cycle heat recovery in all proposed scenarios would increase energy efficiencies by 6.1%, 3.3%, and 1.1%, respectively, to ORC, Kalina, and Goswami cycles. Furthermore, the results of the parametric studies on principal factors such as steam to biomass and equivalence ratios in the gasifier, working fluid types in the ORC, mass fraction of ammonia-water mixture in Kalina and Goswami cycles, as well as thermodynamic properties of the expander and condenser can be highly considered for the energy industry developers.