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Brno University of Technology Vysoké Učení Technické V Brně BRNO UNIVERSITY OF TECHNOLOGY VYSOKÉ UČENÍ TECHNICKÉ V BRNĚ FACULTY OF CHEMISTRY FAKULTA CHEMICKÁ INSTITUTE OF CHEMISTRY AND TECHNOLOGY OF ENVIRONMENTAL PROTECTION ÚSTAV CHEMIE A TECHNOLOGIE OCHRANY ŽIVOTNÍHO PROSTŘEDÍ DEGRADATION OF HEAT TRANSFER FLUIDS IN THERMAL SOLAR SYSTEMS AND PROPANE-1,3-DIOL AS A NEW OPTION STÁRNUTÍ TEPLONOSNÝCH KAPALIN V TERMICKÝCH SOLÁRNÍCH SYSTÉMECH A PROPAN-1,3-DIOL JAKO NOVÁ MOŽNOST DOCTORAL THESIS DIZERTAČNÍ PRÁCE AUTHOR Ing. František Mikšík AUTOR PRÁCE SUPERVISOR prof. Ing. Josef Čáslavský, CSc. ŠKOLITEL BRNO 2018 Zadání dizertační práce Ústav: Ústav chemie a technologie ochrany životního prostředí Student: Ing. František Mikšík Studijní program: Chemie a technologie ochrany životního prostředí Studijní obor: Chemie životního prostředí Vedoucí práce: prof. Ing. Josef Čáslavský, CSc. Akademický rok: 2017/18 Název dizertační práce: Stárnutí teplonosných kapalin v termických solárních systémech a propan–1,3–diol jako nová možnost Zadání dizertační práce: 1. Dlouhodobé sledování a analýza provozu experimentálního termického solárního systému. 2. Identifikace procesů stárnutí teplonosných kapalin na bázi glykolů v termických solárních systémech, určení a charakterizace produktů degradace. 3. Analýza fyzikálních vlastností binární směsi propan–1,3–diolu s vodou. 4. Propan–1,3–diol jako moderní nemrznoucí teplonosná kapalina. Termín odevzdání dizertační práce: 8.6.2018 Ing. František Mikšík prof. Ing. Josef Čáslavský, CSc. doc. Ing. Jiří Kučerík, Ph.D. student(ka) vedoucí práce vedoucí ústavu prof. Ing. Martin Weiter, Ph.D. V Brně dne 1.9.2017 děkan Fakulta chemická, Vysoké učení technické v Brně / Purkyňova 464/118 / 612 00 / Brno ABSTRACT Degradation of heat transfer fluids on an organic basis is a long-standing problem known since the beginning of their use. The first part of this dissertation is devoted to a case study of a functional experimental system that was filled with a propan-1,2-diol based heat transfer fluid upon construction and had been observed for a period of 7 years. Analysis of the fluid aging in this system was conducted by following the basic operating characteristics of the fluid, such as density, viscosity, freezing temperature, pH and metals content. Through these properties, the aging of the fluid was tracked indirectly. Direct observation of the degradation process was then performed by analysis of degradation products such as organic acids formation and changes in the composition of the mixture by isotachophoresis and mass spectrometry. For comparison, selected samples from several other systems filled with identical liquid with an evidently advanced form of degradation were also analysed. The second part of this thesis presents the basic physicochemical properties of aqueous propane-1,3-diol mixtures and their analytical evaluation and mathematical modelling for universal use as a new basis for antifreeze heat transfer fluid. Based on available information, the usability of this mixture is assessed. The advantage of propane-1,3-diol is seen mainly in the renewable production and certain physical and chemical properties, which outweigh the glycols used up to now in several areas. ABSTRAKT Stárnutí teplonosných kapalin na organické bázi je dlouhodobým problémem, který je znám od počátku jejich používání. První část této disertační práce je tak věnována případové studii funkčního experimentálního systému, který byl jako nový naplněn teplonosnou kapalinou na bázi propan-1,2-diol a pozorován po období 7 let. Pro analýzu stárnutí kapaliny v tomto systému byly sledovány základní provozní vlastnosti kapaliny jako jsou hustota, viskozita, teplota tuhnutí, pH a obsah kovů. Skrze tyto vlastnosti tak bylo sledováno stárnutí kapaliny nepřímo. Přímé sledování stárnutí bylo posléze provedeno analýzou degradačních produktů, jako jsou organické kyseliny a změny ve složení směsi pomocí izotachoforézy a hmotnostní spektrometrie. Pro srovnání byly taktéž analyzovány vybrané vzorky z několik dalších systémů plněných identickou kapalinou s prokazatelně pokročilou formou degradace. V druhé části práce jsou představeny základní fyzikálně-chemické vlastnosti směsí propan-1,3-diolu s vodou a jejich analytické hodnocení a matematické modelování pro universální použití jakožto nového základu pro nemrznoucí teplonosné kapaliny. Na základě dostupných informací je pak hodnocena použitelnost této směsi. Výhoda propan-1,3-diolu je spatřována především ve výrobě z obnovitelných zdrojů a v některých fyzikálních a chemických vlastnostech, které dle dosavadních poznatků předčívají doposud používané glykolové směsi. KEYWORDS Heat transfer fluid; Antifreeze; Degradation; Thermal solar system; Propane-1,3-diol; Physicochemical properties KLÍČOVÁ SLOVA Teplonosná kapalina; Nemrznoucí kapalina; Degradace; Termický solární systém; Propan-1,3-diol; Fyzikálně-chemické vlastnosti 3 MIKŠÍK, F. Degradation of heat transfer fluids in thermal solar systems and propane-1,3-diol as a new option. Brno: Brno University of Technology, Faculty of chemistry, 2018. 190 p. Supervisor of the doctoral thesis prof. Ing. Josef Čáslavský, CSc. DECLARATION Prohlašuji, že jsem tuto disertační práci vypracoval samostatně a že všechny použité literární zdroje jsem správně a úplně citoval. Disertační práce je z hlediska obsahu majetkem Fakulty chemické VUT v Brně a může být využita ke komerčním účelům jen se souhlasem školitele a děkana FCH VUT. I declare that I have finished this doctoral thesis by myself and all the literature references are fully and correctly cited. The content of this doctoral thesis is a property of Faculty of Chemistry of Brno University of Technology and can be used commercially only with the consent of the supervisor of this thesis or the dean of the Faculty of Chemistry of Brno University of Technology. ………………………..……….. Podpis doktoranda / Sign of the Ph.D. student ACKNOWLEDGEMENT I would like to express my gratitude to my supervisor professor Čáslavský for valuable comments and advises for this thesis. My gratitude also belongs to my supervisor specialist Dr. Kotlik who had the patience to accept me under his wings and stayed with me until the very end. 4 CONTENT 1 INTRODUCTION ........................................................................................................................................ 7 2 WORK OBJECTIVES................................................................................................................................. 8 3 STATE OF THE ART ................................................................................................................................. 9 3.1 ENERGY SOURCES – RENEWABLE ENERGY SOURCES............................................................................................ 9 3.1.1 Planetary forces and movement ............................................................................................. 10 3.1.2 Nuclear energy ....................................................................................................................... 11 3.1.3 Solar energy – solar radiation ................................................................................................. 12 3.2 TECHNOLOGIES FOR DIRECT USE OF SOLAR ENERGY .......................................................................................... 13 3.2.1 Generating electricity ............................................................................................................. 13 3.2.2 Generating thermal energy .................................................................................................... 15 3.3 THERMAL SOLAR SYSTEMS .......................................................................................................................... 15 3.3.1 Types of solar systems ............................................................................................................ 17 3.3.2 Basic Components .................................................................................................................. 18 3.3.3 Additional components ........................................................................................................... 23 4 THEORETICAL BACKGROUND .......................................................................................................... 24 4.1 OVERVIEW OF HEAT TRANSFER FLUID IN THERMAL SOLAR SYSTEMS ..................................................................... 24 4.1.1 Air ........................................................................................................................................... 24 4.1.2 Water ...................................................................................................................................... 24 4.1.3 HTFs based on silicon oils ....................................................................................................... 24 4.1.4 HTFs based on hydrocarbon oils ............................................................................................. 25 4.1.5 HTFs based on mono-alcohols ................................................................................................ 25 4.2 HEAT TRANSFER FLUIDS BASED ON DIOLS ....................................................................................................... 25 4.2.1 Ethane-1,2-diol (CAS 107-21-1) .............................................................................................. 27 4.2.2 Propane-1,2-diol (CAS 57-55-6) .............................................................................................. 27 4.2.3 Propane-1,3-diol
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