Convegni ATI - Accesso riservato soci CTI

Autore: V. Calicchio, G. Langella, C. Noviello

Collana: BT - 34 - Mag 06 - Energy: production, distribution and conservation

Note:
In this paper a cooling process for flue gas, down to H2O vapour condensation, has been analysed. It has been considered to work a regenerative heat exchanger, something like Ljungstrom pre-heater in big industrial boiler systems; more specifically it has been analysed only a section (UNIT 2) of a more complex regenerative heat exchanger designed for a strong flue gas cooling process in order to reach the temperature needed for CO2 condensation and so segregation, emitting only oxygen and nitrogen (water is condensed yet before).
Heat exchanger which has the shape of a drum, has been divided into a great number of bulk elements, energy and mass balance equation have been written so the model can analyse the temperature distribution, the rate of condensed water and the exchanger efficiency in all the operating conditions (inlet temperature and velocity, rpm of the drum, …).
Analysis results are reported and discussed in diagrams of temperature distribution along the drum, efficiency varying drum rpm, heat exchange coefficients and all the other parameters useful to evaluate the best operating condition of the heat exchanger.
Due to the number of parameters affecting the exchanger efficiency (drum length and rpm, gas velocity and temperature) sensitivity analyses have been carried out, varying each of them while keeping constant the others.