Thermodynamic and economic viability of advanced thermodynamic cycles for power generation in cement plant: case study of Bestway Cement Plant

Cement production significantly contributes to carbon emissions due to energy-intensive processes and escalating demand for construction. Decarbonizing this industry through waste heat recovery is crucial. This study selected three distinct closed thermodynamic cycles for power production utilizing high-temperature waste heat from kiln preheaters of a cement plant located in Pakistan. The analysis is conducted based on thermodynamic assessment considering gross power output and economic assessment considering specific CAPEX as key performance indicators. Considering high ambient temperature conditions at the cement plant site, the cycle gross power output is studied with rise in cycle minimum temperature from 32, 35, and 40
. Moreover, the optimum value of cycle minimum pressure and cycle maximum pressure are determined based on sensitivity analysis. In the realm of economic comparisons, the specific CAPEX of the three layouts is calculated under optimal conditions, considering the harsh scenario of a cycle minimum temperature of 40 °C. The transcritical cycle with a CO2-SO2 mixture appears as the superior choice, exhibiting not only a higher gross power output but also the lowest specific CAPEX, with values of $2713/kWe, $3574/kWe, and $3737/kWe for transcritical CO2 mixture cycle, supercritical CO2 cycle, and Kalina cycle, respectively.