Modelling of a Cascade Organic Rankine Cycle Powered by Exhaust Gas of Benghazi Cement Factory, Libya

We all know that, renewable energy sources such as: solar, wind, geothermal, tidal, and waste heat recovery systems (WHRS) are sustainable and environmentally friendly sources of clean energy. In this paper hot exhaust gases, which were produced by one of Benghazi Cement factories production lines at an elevated temperature of 300 ?C and at mass flow rate of 5660 m3/min, were utilized to power a cascade organic Rankin cycle for electricity generation purposes. In order to fully utilize this wasted energy, a thermodynamic model was schematically constructed using a commercial software package called IPSEpro. The model (using two environmentally friendly refrigerants (R - 123, R - 245fa)), was successfully simulated and validated to produce 1030 kW of electricity at reasonable cycle thermal efficiency of 5.6 %, and also to minimize emissions of harmful gases to the atmosphere.