Dynamics of Adsorptive Systems for Heat Transformation (eBook)

Dr.-Eng. Alessio Sapienza He graduated in Material Engineering at the University of Messina, Italy, in 2004. He completed his PhD in Chemical and Materials Engineering at the University of Messina in 2012. Currently he has been working as researcher at the Italian National Council of Research - Institute for Advanced Energy Technologies (CNR-ITAE), Messina since 2005. The scientific activity of Dr.-Eng. Alessio Sapienza is mainly focused on the development and characterization of adsorbent materials, components and prototypes for adsorption heat pumps/chillers and on advanced energy systems. He published more than 40 printed papers. Dr.-Eng. Angelo Freni He graduated in Materials Engineering at the University of Messina in 1998. He holds a Ph.D. in Materials and Chemical engineering from the University of Messina. He has been at the Italian National Council of Research - Institute for Advanced Energy Technologies (CNR-ITAE), Messina, since 1998. He has worked on thermally-driven heat pumps, heat and hydrogen storage, has published more than 130 printed papers in the field, plus 3 patents. He has been carrying out and leading scientific activities in the framework of National and International programs, in co-operation with industries and research groups. Currently, he is Head of the research group on “Thermally Driven Heat Pumps” at CNR ITAE. He is the Italian alternate delegate in the Executive Committee of the Heat Pump Programme of the International Energy Agency. He is member of the commission “E2 - Heat pumps, energy recovery” of the IIR – International Institute of Refrigeration Dr.-Eng. Andrea Frazzica He graduated in Material Engineering at the University of Messina, Italy, in 2008. He completed his PhD in Chemical and Materials Engineering at the University of Messina in 2012. Currently he is working as post-doctor researcher at the Italian National Council of Research - Institute for Advanced Energy Technologies (CNR-ITAE), Messina. The scientific activity of Dr.-Eng. Andrea Frazzica is mainly focused on the development and characterization of adsorbent materials and components for TDHPs and on advanced materials and systems for thermal energy storage. He published more than 30 printed papers. Prof. Yuri Aristov He graduated from the Moscow Physical-Technical Institute in 1977 (M.Sc degree). He is a Professor of Physical Chemistry and a Head of Group of Energy Accumulating Materials and Processes at the Boreskov Institute of Catalysis (BIC), Novosibirsk, Russia. He received his Ph.D. (1984) and Doctoral (2003) degrees from BIC. His research contributions were in the field of radiation chemistry, low temperature electron tunneling, fractal analysis of porous solids, thermochemical transformation of heat. He is currently working on novel composite adsorbents for adsorptive heat transformation, gas drying, maintaining relative humidity in museums, as well as on heat and mass transfer in adsorptive heat transformers. He has published c.a. 200 papers and 26 patents.

Acknowledgements 6
Contents 7
1 Adsorptive Heat Transformation and Storage: Thermodynamic and Kinetic Aspects 9
1.1 Thermodynamic Cycles for AHT 11
1.1.1 Temperature-Driven Cycles 12
1.1.2 Pressure-Driven Cycles 13
1.1.3 Other Presentations of the AHT Cycles 15
1.2 The AHT Efficiency 16
1.2.1 The First Law Efficiency 16
1.2.2 The Second Law Efficiency 17
1.3 Dynamics of AHT Cycles 18
1.4 Adsorbents Optimal for AHT 20
1.4.1 The First Law Efficiency 21
1.4.2 The Second Law Efficiency 21
1.4.3 Adsorbent Optimal from the Dynamic Point of View 22
References 24
2 Measurement of Adsorption Dynamics: An Overview 27
2.1 Differential Step (IDS) Method 29
2.2 Large Pressure Jump (LPJ) Method 30
2.3 Large Temperature Jump (LTJ) Method 32
2.3.1 Volumetric Large Temperature Jump Method (V-LTJ) 33
2.3.2 Gravimetric Large Temperature Jump Method (G-LTJ) 35
References 36
3 Experimental Findings: Main Factors Affecting the Adsorptive Temperature-Driven Cycle Dynamics 38
3.1 Adsorbate and Adsorbent Nature 39
3.1.1 Water Sorption Dynamics 40
3.1.2 Methanol Sorption Dynamics 41
3.2 Adsorbent Grain Size 42
3.2.1 Water Sorption Dynamics 43
3.2.2 Methanol Sorption Dynamics 48
3.2.3 Ethanol Sorption Dynamics 51
3.3 Geometry of the Adsorber 55
3.3.1 Water Sorption Dynamics 56
3.3.2 Methanol Sorption Dynamics 56
3.3.3 Ethanol Sorption Dynamics 59
3.4 Cycle Boundary Conditions 64
3.4.1 Methanol Sorption Dynamics 64
3.4.2 Ethanol Sorption Dynamics 67
3.5 Residual Gases 68
3.5.1 Water Sorption Dynamics 69
3.6 Flux of Cooling/Heating Heat Carrier Fluid 72
References 73
4 Optimization of an “Adsorbent/Heat Exchanger” Unit 76
4.1 Optimization of the “Adsorbent—Heat Exchanger” Unit 78
4.1.1 Adsorbent Grain Size 78
4.1.2 The Ratio “Heat Transfer Surface”/“Adsorbent Mass” 81
4.1.3 The Effect of the Flow Rate of External Heat Carrier 83
4.1.4 Comparison of the Model Configurations with Full-Scale AHT Units 85
4.2 Compact Layer Versus Loose Grains 86
4.3 The Effect of Residual Gases 88
4.4 Reallocation of Adsorption and Desorption Times in the AHT Cycle 91
References 92