4 Advanced steam cycles Text

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COURSE OF ENERGY CONVERSION A 2014/2015 Prof. G. Valenti 4th Project Advanced steam cycles The present project aims at calculating the performance of diverse steam cycle configurations throughout the use of the software package CicVap. Consider as a reference plant configuration the ultra-supercritical steam cycle, namely configuration A; it is characterised by the following main features (as far as the other paramete rs are concerned, make reference to the attached tables): Configuration A - Superheater outlet mass flow rate: 1˙850˙000 kg/h - Superheater outlet steam pressure: 270 bar - n re-heaters: 1 - n pre-heaters (deaereator included) : 8 (4 BP, 4 AP) - n intermediate-pressure two-flow rotors: 2 - n low-pressure two-flow rotors: 4 - last stage blading: 33.5 inches – mean diameter 99.5 inches - steam temperatures: 580C / 580C - condensing pressure: 0.05 bar - fuel: coal - exhaust gases stack temperature 150 C - O2 concentration in exhaust gases at the stack: 5% - economiser water inlet temperature: ~ 315 C Furthermore, consider the following cycle configurations which are different from configuration A by the hereby mentioned characteristics (all the parameters which have not been reported remain equal to the former case A): Configuration B - fuel: natural gas - exhaust gases stack temperature: 120 C - stack O2 concentration in exhausts: 2.5% Configuration E - n regenerators: 4 (2 LP deaereator included, 2 HP) - economiser water inlet temperature: ~ 280 C Configuration C - condensing pressure: 0.1 bar Configuration F - n re-heaters: 2 - steam temperatures: 580°C/580°C/580°C Configuration D - steam temperatures: 640C / 640C The water temperature increase during the regeneration process is assumed to be equally divided among all the regenerators for…