First and second law-based thermal optimisation of the Kalina cycle integrated into an existing burner-based cogeneration system using waste chips as fuel

Abstract

Due to increasing energy demand and decreasing fossil resources, the optimisation of existing systems has a critical role to minimise energy consumption and diminish the adverse effect of power systems on the environment. Therefore, the main interest of researchers is mainly focused on developing a new combined system to use energy sources more efficient. In the present study, a KC was integrated into an existing burner, which uses waste chips as fuel for producing steam and drying moist fibre. The KC was analysed based on the first and second law of thermodynamics and thermally optimised. After detailed analyses for varying turbine inlet temperature at 50 bar (up to 330°C) and water-ammonium concentrations (from X = 20% to X = 80%), maximum net power, thermal and exergy efficiencies of KC were found as 348.73 kW, 22.7% and 52.7% at T = 330°C and X = 80%, respectively. For the overall cogeneration system, the maximum thermal and exergy efficiencies were calculated as 71.77% and 77.86% at X = 80%, respectively.