Eventos Anais de eventos
ENCIT 2016
16th Brazilian Congress of Thermal Sciences and Engineering
THERMOECONOMIC ANALYSIS OF A KALINA CYCLE FOR WASTE HEAT RECOVERY
Submission Author:
Felipe Raul Ponce Arrieta , MG
Co-Authors:
Gustavo Rodrigues da Costa Horta, Cláudio Silva
Presenter: Felipe Raul Ponce Arrieta
doi://10.26678/ABCM.ENCIT2016.CIT2016-0432
Abstract
Thermoeconomic analysis, based on EES (Engineering Equation Solver) model, of a Kalina cycle for waste heat recovery aims to optimize the exergoeconomic indexes of a modified Kalina Cycle with 2 turbines. The model has as the main objective the optimization to minimize the unit exergetic cots and unit exergoeconomic costs and maximize the electric power generation of the Kalina Cycle using the preheater exhaust gases in a 5000 clink t/d cement plant. We carried out parametric studies in order to evaluate the best operating point as function of turbine inlet pressure and temperature and ammonia mass fraction concentration in the working fluid. The model uses the thermo physical properties of the working fluid provided by the function NH3-H20 of the EES library. We implemented the mass, energy and entropy balances for each equipment and a modification of the exergetic cost structural theory. The model includes cost information curves from National Energy Technology Centre (USA) with values corrected to the end of 2013. In the results, we found that the cycle as able to produce 2 MW of electric power with a cost of 228.7 R$/MW and the unit exergetic cost of 2.322. The optimized parameters of the cycle are ammonia mass fraction of 0.5, the first turbine inlet pressure of 100 bar, the second turbine inlet pressure of 15 bar and the superheating temperature of 598.15 K. We concluded that the use of a second turbine increase in 735 kW the electricity production but implies in a second subsystem of distillation and absorption, rising the investment costs. In spite of it, the power generation cost is competitive in the existing Brazilian’s electric market.
Keywords
thermoeconomic, Waste heat, Exergy Analysis, thermodynamic
