Binary Power Cycles Universitat Rovira i Virgili Doctorate Program in Chemical and Process Engineering Department of Chemical and Mechanical Engineering New Working Fluids For The Binary Power Cycles Tuesday 3 of February 2005, Tarragona Spain. Driss BAHJA 2005 URV New Working Fluids For The Binary Power Cycles Tuesday 3 of February 2005, Tarragona Spain. Driss BAHJA 2005 URV

Binary Power Cycles Contents: Organic Rankine Cycles Ammonia Power Cycles New Working Fluid Conclusion

Binary Power Cycles The goal of our investigation is to improve the thermal efficiency of the power cycles by minimizing the entropy generated. For this purpose we have investigated the using of the NH3-H2O as binary working fluid and other fluids for the Organic Rankine Cycle. The irreversibilities depends on the types of the working fluids and heat sources. A cycle with lower irreversibility results in a better performance.

Binary Power Cycles Organic Rankine Cycle

Binary Power Cycles

Dry and Isentropic Working fluids are the more appropriate for the ORC

Binary Power Cycles The selection of suitable organic fluids for use in (ORC) still deserves intensive thermodynamic and physical study of the working fluids. The thermodynamic characteristics give rise to thermodynamic limitations to the amount of energy that can be extracted from the heat source.

Binary Power Cycles Maximum and minimum pressure for ORC Pc Tc Pmax 120 ºCPmin Bar 25ºC Isobutane 36,4134,7< 25 Bar 3,504 Isopentane 33,7187,2< 10 Bar 0,9169 n-Butane 37,96152< 20 Bar 2,437 n-Hexane 30,58234,7< 5 Bar 0,2026 n-Pentane 33,64196,5< 7 Bar 0,6892 Water 220,6374< 3 Bar 0,03169 R11 44,08198< 12 Bar 1,056 R12 41,14112< 40 Bar 6,511 R114 32,89145,7<20 Bar 2,132 R123 36,68183,7< 12 0,9148 R141b 42,49204,2< 10 Bar 0,7847 R152a 45,2113,3< 40 Bar 5,972 Maximum and minimum pressure for ORC Pc Tc Pmax 120 ºCPmin Bar 25ºC Isobutane 36,4134,7< 25 Bar 3,504 Isopentane 33,7187,2< 10 Bar 0,9169 n-Butane 37,96152< 20 Bar 2,437 n-Hexane 30,58234,7< 5 Bar 0,2026 n-Pentane 33,64196,5< 7 Bar 0,6892 Water 220,6374< 3 Bar 0,03169 R11 44,08198< 12 Bar 1,056 R12 41,14112< 40 Bar 6,511 R114 32,89145,7<20 Bar 2,132 R123 36,68183,7< 12 0,9148 R141b 42,49204,2< 10 Bar 0,7847 R152a 45,2113,3< 40 Bar 5,972

Binary Power Cycles Working fluids performance

Binary Power Cycles Optimization of the ORC n-pentane R11 η 0,1192 0,1496 Q_Boiler KW W_net KW T_max ºC T_min ºC P_max 9,905 13,4 Bar P_min 1,088 1,628 Bar Optimization of the ORC n-pentane R11 η 0,1192 0,1496 Q_Boiler KW W_net KW T_max ºC T_min ºC P_max 9,905 13,4 Bar P_min 1,088 1,628 Bar

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n-pentane n-butane thermal efficiency

Binary Power Cycles n-pentane n-butane Net Work

Binary Power Cycles Comparison of different correlation of NH3-H2O

Binary Power Cycles Variation of the enthalpy Ibrahim Klein

Binary Power Cycles Comparison of Water NH3-H2O HRGV NH3-H2O has better performance the temperature difference between the heat source and the working fluid is small.

Binary Power Cycles Rankine using NH3-H2O thermal efficiency variation

Binary Power Cycles Rankine using NH3-H2O Net work

Binary Power Cycles KSC34 Kalina Cycle

Binary Power Cycles KCS 34 Thermal efficiency variation

Binary Power Cycles Variation of thermal efficiency with the Net Work

Binary Power Cycles KCS11 Kalina Cycle

Binary Power Cycles KCS11 thermal efficiency variation w

Binary Power Cycles KCS11 Net Work Variation

Binary Power Cycles Kalina Cycle as bottoming cycle

Binary Power Cycles Comparison between Rankine and Kalina Cycle as bottoming cycle Maximum power Rankine at 40,98 Bar

Binary Power Cycles Comparison of thermal efficiencies: η = 0,3043 Rankine η = 0,338 Kalina

Binary Power Cycles New Working Fluid For the NH3-H2O Power cycle We will review the VLE data with the objective to identify the new working fluid with wide boiling temperature range. Working fluid will be eliminated if they will be toxic or flammable. We will use the classical equation of states to calculate the thermodynamic properties.

Binary Power Cycles

Conclusion: Our simulation of the ORC and the Kalina cycles have permit us to compare between the two power cycles. The Ammonia-water has the advantage to boil at variable temperature which permit the fluid to match the heat source better than the steam for high pressure and temperature. n-Butane have the better performance as working fluid in the ORC.

Binary Power Cycles Successful development of an alternative to the ammonia- water Kalina cycle will provide new possibilities for improving the cycle efficiency. Identification of a binary mixture, with a wide boiling range that can be adjusted to various temperature heat sources may allow its use not only as working fluid in the primary cycle, but also in bottoming cycles.