Heat recovery from Diesel engines: a thermodynamic comparison between Kalina and ORC cycles

Paola Bombarda , Costante Invernizzi , Claudio Pietra

In the context of heat recovery for electric power generation, Kalina cycle (a thermodynamic cycle using as working fluid a mixture of water and ammonia) and Organic Rankine Cycle (ORC) represent two different eligible technologies. In this work a comparison between the thermodynamic performances of Kalina cycle and an ORC cycle, using hexamethyldisiloxane as working fluid, was conducted for the case of heat recovery from two Diesel engines, each one with an electrical power of 8900 kW e. The maximum net electric power that can be produced exploiting the heat source constituted by the exhaust gases mass flow (35 kg/s for both engines, at 346°C) was calculated for the two thermodynamic cycles. Owing to the relatively low useful power, for the Kalina cycle a relatively simple plant layout was assumed. Supposing reasonable design parameters and a logaritmic mean temperature difference in the heat recovery exchanger of 50 °C , a net electric power of 1615 kW and of 1603 kW respectively for the Kalina and for the ORC cycle was calculated.

Mots clés: Organic Rankine Cycles; ORC; Ammonia–Water Cycles; Kalina cycles; bottoming cycles; Diesel engines; thermodynamic conversion cycles

Paola Bombarda, Costante Invernizzi, Claudio Pietra. Heat recovery from Diesel engines: a thermodynamic comparison between Kalina and ORC cycles. Applied Thermal Engineering, 2009, 30 (2-3), pp.212. ⟨10.1016/j.applthermaleng.2009.08.006⟩. ⟨hal-00521157⟩