Research on Heat Conversion Systems for Power and Refrigeration

Transcription

1 Research on Heat Conversion Systems for Power and Refrigeration Prof. Dr. Alberto Coronas Group of Applied Thermal Engineering CREVER Mechanical Engineering Department Universitat Rovira i Virgili, Tarragona Campus of International Excellence Southern Catalonia (CEICS) Forum th November 2011

2 CREVER-URV CREVER is the Group of Applied Thermal Engineering of the Mechanical Engineering Department. CREVER is a multidisciplinary group with 9 doctors, 10 PhD students, several master s students, erasmus students and exchange students from different countries. The tasks and objectives of CREVER are focused on the development of advanced energy conversion technologies in cooperation with partners from industry and public sector. 2

3 Heat Conversion Systems Among all Heat Conversion Systems, CREVER-URV research focuses on absorption heat pumps and chillers driven by thermal energy ( waste heat, solar thermal energy, exhaust combustion gases,.) Most commonly used working pairs are NH 3 /H 2 O and H 2 O/LiBr The technological development of absorption technologies for some interesting applications ( solar air conditioning, solar refrigeration, high efficiency multi-effect systems driven by high temperature thermal heat sources,..) is limited by the physico-chemical properties of the conventional working pairs. 3

4 Absorption technology NH 3 /H 2 O: Industrial refrigeration - Evaporation temperature < 0ºC H 2 O/LiBr : Air-conditioning applications Evaporation temperature > 5ºC Drawbacks of NH 3 /H 2 O - Toxicity - High working pressures - Rectification Drawbacks of H 2 O/LiBr - Crystallization - Corrosion - Restricted temperature lift due to crystallization - Use of cooling towers 4

5 Research on Heat Conversion Systems for Power and Refrigeration New working fluids for absorption systems Determination and Modelling of thermophysical properties of new working fluids and materials Development and simulation of new absorption cycles Study of heat and mass transfer in sorption processes Development of new components for absorption chillers for different working fluids and applications Characterisation, evaluation and modelling of different absorption chillers (prototypes or commercial) in a test bench Analysis, simulation and optimization of polygeneration systems Implementation of polygeneration systems in the framework of different projects

6 New working fluids for absorption systems New working fluids for absorption refrigeration systems developed: - Addition of NaOH to NH 3 /H 2 O to improve the separation of ammonia in the generator and reduce both chiller driving temperature and rectification losses. - Use of NH 3 /LiNO 3 (+H 2 O) to avoid the need of rectification and reduce the driving temperature heat source. - Ionic Liquids as absorbents - Organic salts with no measurable vapor pressure. - Melting points lower than 100 C. - Liquid temp. range K. - Less corrosive than conventional high melting salts. - Tailor-made properties of ILs by selection of cations and anions. Advantages of NH 3 /IL or H 2 O/IL - Non-volatile - Non-corrosive - Thermal stability - Stable towards hydrolysis - Homogeneous mixture with water - Adequate heat and mass transfer - Compatibility with standard materials 6

7 Research on Heat Conversion Systems for Power and Refrigeration New working fluids for absorption systems Determination and Modelling of thermophysical properties of new working fluids and materials Development and simulation of new absorption cycles Study of heat and mass transfer processes in sorption components Development of new components for absorption chillers for different working fluids and applications Characterisation, evaluation and modelling of different absorption chillers (prototypes or commercial) in a test bench Analysis, simulation and optimization of polygeneration systems Implementation of polygeneration systems in the framework of different projects

8 Thermopysical properties of new working fluids and materials EXPERIMENTAL Implementation of new measurement techniques and methodologies. Experimental determination of thermophysical properties of pure fluids and mixtures: Vapour pressure Density Dynamic and kinematic viscosity Solubility of solids in solvents Heat capacity Thermal conductivity Enthalpy of mixing CALCULATIONS Correlation of experimental results. Determination of excess properties. Modeling of phase equilibria PTX, HTX diagrams MODELS Proposal of thermodynamic methods for estimation and prediction of thermophysical properties. 8

9 Thermopysical properties of new working fluids and materials Measurement of thermodynamic and transport properties of pure fluids and mixtures (I) Equipment for vapour-pressure measurement Heat capacity measurement Thermal conductivity measurement 9

10 Thermopysical properties of new working fluids and materials Measurement of thermodynamic and transport properties of pure fluids and mixtures (II) Solubility measurement 4 1.Falling ball 2.Type-piston 3.Ubbelhode capillary 4.Vibrating Density measurement Viscosity measurement 10

11 Thermopysical properties of new working fluids and materials Modelling of Thermophysical Properties Thermodynamic Models Phase Equilibria Correlations Source: Herraizm J. Shen, S., Coronas,A. Vapor-Liquid equilibria for the methane + poly(ethylene glycol) 250 dimethil ether Source: Conesa, A; Shen, S; Coronas, A. INTERNATIONAL JOURNAL OF THERMOPHYSICS, Vol 19, 5, ,

12 Thermopysical properties of new working fluids and materials Separation of NH 3 /H 2 O/NaOH mixtures using Reverse Osmosis membranes for low temperature driven absorption chillers Reverse Osmosis Cell Hydraulic pump Experimental Reverse Osmosis Cell at laboratory scale Feed pump 12

13 Research on Heat Conversion Systems for Power and Refrigeration New working fluids for absorption systems Determination and Modelling of thermophysical properties of new working fluids and materials Development and simulation of new absorption cycles Study of heat and mass transfer processes Development of new components for absorption chillers for different working fluids and applications Characterisation, evaluation and modelling of different absorption chillers (prototypes or commercial) in a test bench Analysis, simulation and optimization of polygeneration systems Implementation of polygeneration systems in the framework of different projects

14 Development and simulation of new absorption cycles Simulation of absorption cycles with new mixtures Pressure Q C Q G 0,8 5 P a P b Evaporator Condenser Refrigerant expansion valve VE2 E Q E W Pump 1 C A Q A 2 B HESS G 4 Generator Solution Heat exchanger 5 Solution expansion valve VE1 Absorber COP 0,7 0,6 0,5 0,4 0,3 0,2 0,1 0 Tgen=80 C Tgen=90 C Tgen=100 C Viscosity (mpas) T E T A T G Temperature Tab/cond ( C) COP 0,8 0,7 0,6 0,5 0,4 0,3 0,2 0, Tab/cond ( C) Tgen=80 C Tgen=90 C Tgen=100 C Viscosity (mpas) Ammonia/Lithium nitrate mixture Ammonia/(Lithium nitrate + water) M=

15 Research on Heat Conversion Systems for Power and Refrigeration New working fluids for absorption systems Determination and Modelling of thermophysical properties of new working fluids and materials Development and simulation of new absorption cycles Study of heat and mass transfer in sorption processes Development of new components for absorption chillers for different working fluids and applications Characterisation, evaluation and modelling of different absorption chillers (prototypes or commercial) in a test bench Analysis, simulation and optimization of polygeneration systems Implementation of polygeneration systems in the framework of different projects

16 Study of heat and mass transfer processes Study of heat and mass transfer in sorption processes Heater 3 HEATING Magnetic T T P T CONDENSING CIRCUIT CIRCUIT flowmeter Magnetic T flowmeter P T PRE-HEATER CIRCUIT SECTION TEST T Heater 2 MAIN LOOP Condenser T Coriolis T BP Vortex flowmeter T Heater 1 T P Level TANK Solution Pump Generator and Absorber test bench P Neutralization tank TEST SECTION C T VLS T P T P C Solution tank Neutralization tank Storage tank NH 3 bottle Plate heat exchanger Tap water Mass Absorption Flux [g/s.m 2 ] 9,0 8,0 7,0 6,0 5,0 4,0 3,0 2,0 1,0 Heat trasfer coefficient (kw m -2 K -1 ) q"=50 kw m -2 q"=40 kw m -2 q"=30 kw m -2 q"=20 kw m -2 G=100 kg m -2 s -1 P=15 bar w=0.42 ammonia Mean vapour quality 12,0 11,0 10,0 0,0 0, Solution Mass flow (Kg/h) FAB PHE L FAB PHE H FAB S&THE microf HTC PHE L HTC PHE H HTC S&THE MicroF 9,0 8,0 7,0 6,0 5,0 4,0 3,0 2,0 1,0 Solution Heat Transfer Coefficient [kw/m 2 k] 16

17 Study of heat and mass transfer processes Modeling of heat and mass transfer in sorption processes COND Ammonia mass fraction NH 3+LiNO 3+H 2O NH 3+H 2O Case GEN T GENERATOR (C) 17

18 Research on Heat Conversion Systems for Power and Refrigeration New working fluids for absorption systems Determination and Modelling of thermophysical properties of new working fluids and materials Development and simulation of new absorption cycles Study of heat and mass transfer in sorption processes Development of new components for absorption chillers for different working fluids and applications Characterisation, evaluation and modelling of different absorption chillers (prototypes or commercial) in a test bench Analysis, simulation and optimization of polygeneration systems Implementation of polygeneration systems in the framework of different projects

19 Development of new components and prototypes for absorption chillers Design and construction of prototypes 19

20 Research on Heat Conversion Systems for Power and Refrigeration New working fluids for absorption systems Determination and Modelling of thermophysical properties of new working fluids and materials Development and simulation of new absorption cycles Study of heat and mass transfer in sorption processes Development of new components for absorption chillers for different working fluids and applications Characterisation, evaluation and modelling of different absorption chillers (prototypes or commercial) in a test bench Analysis, simulation and optimization of polygeneration systems Implementation of polygeneration systems in the framework of different projects

21 Characterization and modelling of absorption chillers in a test bench Characterisation, evaluation and modelling of different absorption chillers (prototypes or commercial) in a test bench Scheme of the multifuntional test bench implemented in the laboratories of CREVER-URV 21

22 Characterization and modelling of absorption chillers in a test bench Data Reconciliation of Absorption Chillers and Heat Pumps Measurements Data Reconciliation Optimal adjustment of measurements in order to satisfy the mass and energy balances. Optimal operation Empirical models* Fault detection Process control Soft sensors Parameter estimation Thermodynamic Model * Development of empirical or semi-empirical models (such as Characteristic Equation or Artificial Neural Networks) to be integrated into polygeneration optimization packages. 22

23 Research on Heat Conversion Systems for Power and Refrigeration New working fluids for absorption systems Determination and Modelling of thermophysical properties of new working fluids and materials Development and simulation of new absorption cycles Study of heat and mass transfer processes Development of new components for absorption chillers for different working fluids and applications Characterisation, evaluation and modelling of different absorption chillers (prototypes or commercial) in a test bench Analysis, simulation and optimization of polygeneration systems Implementation of polygeneration systems in the framework of different projects

24 Analysis, simulation and optimization of polygeneration systems Analysis and optimization of trigeneration configurations in buildings (I) - Analysis of different trigeneration configurations integrating different CHP systems. Microgas turbine - Modeling of thermodynamic characteristics of different thermally driven refrigeration systems and validation with experimental tests. - Proposition of several configurations for advanced refrigeration systems using waste/heat maximizing the waste heat recovery and optimising the integration of microtrigeneration systems. Internal combustion engine Fuel cell 24

25 Analysis, simulation and optimization of polygeneration systems Analysis and optimization of trigeneration configurations in buildings (II) Schematic diagram of a MGT+DE trigeneration system Analysis and optimization to maximise the Waste Heat Recovery and optimise the integration in buildings Schematic diagram of the MGT+SE trigeneration system Schematic diagram of the FC+SE trigeneration system 25 Schematic diagram of a ICE+SE/DE trigeneration system

26 Analysis, simulation and optimization of polygeneration systems Modelling and simulation of combined power and refrigeration absorption systems driven by solar energy Literature review on the current state of the art on absorption and solar thermal systems Identification of parameters useful for comparing cycle configurations based on heat exchangers, heat source & sink characteristics Study of ammonia based working fluid pairs (ammonia/water and ammonia/salts) Selection of cycle configurations for simultaneous generation of power & refrigeration (for buildings & small industries application) Cycle modelling & simulation using different working fluid pairs Detail modelling, simulation and operational parameter optimization of the integrated plant (solar field, absorption power & refrigeration system) for specific thermal boundaries and geographic location 26

27 Analysis, simulation and optimization of polygeneration systems Optimization models for polygeneration systems Development of optimization models using mathematical programming techniques for the optimal design and operation of polygeneration systems including economical and environmental parameters in the objective function. The models can be used to select the type of units to be used in the polygeneration system, the optimal size of each unit or the operation strategy of the system, according to an energy demand and the cost of the energy and the units (cogeneration engines, chillers, energy storage ). The optimization model for each unit is defined inside blocks with several input and outputs, by connecting these blocks any polygeneration system can be defined. Inputs to the model Demand restrictions Use of technologies Operational restrictions Equipment and energy costs Objective function GAMS Inputs / output of the models Outputs Equipment nominal power Operational conditions Operational and investment costs Environmental parameters User friendly interface developed to define the polygeneration system 27

28 Research on Heat Conversion Systems for Power and Refrigeration New working fluids in absorption systems Determination and Modelling of thermophysical properties of new working fluids and materials Development and simulation of new absorption cycles Study of heat and mass transfer processes Development of new components (absorber and generator) for absorption chillers for different working fluids and applications Characterisation, evaluation and modelling of different absorption chillers (prototypes or commercial) in a test bench Analysis, simulation and optimization of polygeneration systems Implementation of polygeneration systems in the framework of different projects

29 Implementation of polygeneration systems in different projects HEGEL Project (I) HEGEL was a project aimed to develop, demonstrate and compare high efficiency applications of micropolygeneration. Three demonstration plants were tested: Combined Cycle Application Installed in Turkey CRF COGENERATOR ICED CHP + Desiccant DuCool Installed in Italy Micro Turbine Capstone C30 MT + Absorption Robur Thermal Oil Driven Installed in Spain ICE-Desiccant A trigeneration plant in Politecnico di Torino (Italy) Combi System A small-size combined-cycle in Middle Technical University, in Ankara (Turkey) MT-Absorption A trigeneration plant in a Districlima in Barcelona (Spain). 29

30 Implementation of polygeneration systems in different projects HEGEL Project (II) Characterisation and integration of a microturbine for microtrigeneration applications. Installation of the microtrigeneration in CREVER-URV pilot plant 30

31 Implementation of polygeneration systems in different projects HEGEL Project (III) Installation of the microtrigeneration system in Districlima (Barcelona) 31

32 Implementation of polygeneration systems in different projects POLYCITY Project (I) The system consists of distributed polygeneration plants including renewable energy sources connected to a district heating and cooling network (DHC) and exporting electricity to the grid. 32

33 Implementation of polygeneration systems in different projects POLYCITY Project (II) District Heating & Cooling Network SE Absorption chillers DE Absorption chillers High efficiency cogeneration Biomass gasification Solar thermal plant 33

34 Implementation of polygeneration systems in different projects POLYCITY Project (III) ST-4 Polygeneration Plant in Cerdanyola del Vallès (Barcelona, Spain) 34

35 Some ongoing Research Projects 35

36 Thank you for your attention Research on Heat Conversion Systems for Power and Refrigeration Prof. Dr. Alberto Coronas Group of Applied Thermal Engineering CREVER Mechanical Engineering Department Universitat Rovira i Virgili, Tarragona Campus of International Excellence Southern Catalonia (CEICS) Forum th November 2011