Applications of Process Engineering Principles in Materials Processing, Energy and Environmental Technologies: An EPD Symposium in Honor of Professor Ramana G. Reddy: Energy Storage and Engineering Issues
Sponsored by: TMS Extraction and Processing Division, TMS Light Metals Division, TMS: Energy Committee, TMS: Hydrometallurgy and Electrometallurgy Committee
Program Organizers: Shijie Wang, Rio Tinto Kennecott Utah Copper; Michael Free, University of Utah; Shafiq Alam, University of Saskatchewan; Mingming Zhang, Arcelor Mittal; Patrick Taylor, Colorado School of Mines
Thursday 8:30 AM
March 2, 2017
Location: San Diego Convention Ctr
Corrosion Mitigation Approaches for High Temperature Energy Production: Judith Vidal1; 1National Renewable E
Next-generation concentrating solar power (CSP) applications will require advanced heat-transfer fluids and thermal-storage materials that work from about 550°C to at least 720°C. Several high-temperature fluid candidates–such as molten salts, liquid metals and supercritical CO2–have been identified to work in that range. Advanced components are required for integration with advanced power-conversion systems. There is an agreement that molten-salt thermal energy storage is excellent for CSP systems based on the design’s efficiency, established performance and acceptance in industry. Approaches for corrosion mitigation are being investigated and optimized to drive down corrosion rates to acceptable levels—in the order of tens of micrometers per year—for achieving a long system lifetime of at least 30 years. Corrosion mitigation approaches being evaluated will be presented showing their advantages and disadvantages based on corrosion results, costs associated with the alloys and processes, and feasibility to be established at a pilot- or demonstration-scale.
High-Temperature High-Efficiency Latent Heat Based Thermal Energy Storage System: Development and Performance Testing: Dileep Singh1; 1Argonne National Laboratory
The focus of the presentation is on the development of a high efficiency latent heat based thermal energy storage (LHTES) system. As part of this work, we have impregnated high thermal conductivity, low-density graphite foams with a phase change material (PCM) salt, thereby, offering a composite system with conductivities significantly greater than the salt alone, allowing rapid charge/discharge cycles. Simulations have been conducted for the proposed LHTES system for a 100 MWe concentrating solar electric power (CSP) plant with 8 h storage. Three-dimensional (3-D) heat transfer simulations were conducted for the storage system using commercial software COMSOL. The results show that the graphite foam can considerably enhance the heat transfer performance and round trip efficiencies of the LHTES system. As part of this presentation, experimental results from prototype development and the associated charging and discharging tests will be discussed and compared with the simulations.
Thermal Energy Storage in Orientationally Disordered “Plastic Crystals”: Dhanesh Chandra1; Renhai Shi1; Murli Tirumala1; Daryl Nelson1; 1Uni. of Nevada, Reno
Fossil fuels are increasing carbon footprint in the world; to mitigate this thermal energy storage materials are gaining importance. Thermal energy storage materials in organic “Plastic Crystals” such as C(CH2OH)4-PE, (CH3)C(CH2OH)3-PGand a few others, store a large amount of thermal energy during first order solid state phase transitions. A handful of these materials are commercially available that have fixed phase transition temperatures, so solid solutions are with different phase transition temperatures to make more materials available. We recently found that “Continuous Phase Transitions,” can store significant amount of heat but in a wide range of temperature, mimicking “stepped” first order phase transitions. The CALPHAD calculations allow development of a wide range of materials with optimum energy storage properties. Issues related to extrapolation of Gibbs energy functions from heat capacity data, isotherms of selected ternary systems, pseudo-binary isopleths from the ternaries will be present.
Corrosion Mechanism of Haynes 230 with Ni Crucible in MgCl2-KCl: Yuxiang Peng1; Ramana Reddy1; 1The University of Alabama
The long-term corrosion behavior of Haynes 230 alloy in KCl-MgCl2 salt at 1000oC was evaluated in current study. The test was performed at 1000oC for 500 hours in Ni crucible under an argon cover gas. In this test, Haynes 230 alloy shows good corrosion resistance. In addition, corrosion was noted to occur by depletion of Cr. And the Cr deposition on the Ni crucible proves that corrosion mechanism may be galvanic corrosion. Thus, Gibbs energy of Ni-Cr alloy is studied based on the thermodynamic calculation. And thermodynamic modeling studies are performed with Nernst equation to understand the potential of cathode and anode at 1000oC. To compare with experimental data, tafel prediction is studied based on the known exchange current density and tafel slope.
9:50 AM Break
Functional Syntactic Foams: Titania Coated Glass Microballoons for Environmental Cleanup: Krishan Chawla1; 1University of Alabama at Birmingham
Syntactic foams consist of hollow spheres distributed in a small amount of matrix material. The word syntactic comes from Greek meaning to arrange parts together in a unit. Functional syntactic foams are syntactic foams made for a specific objective other than that of enhanced compressive properties. We have developed titania coated glass microballoons (GMBs) with high surface area. The objective is to use syntactic foams based on titania coated GMBs for water purification. I describe the processing by sol-gel of titania-coated glass microballoons (GMBs) and sintering of these coated microballoons to form functional syntactic foam for environmental applications. Processing of coated GMBs starting with titanium isopropoxide precursor, microstructure of the coated GMBs, and critical materials related issues in environmental cleanup applications are highlighted.
Conceptualization of Doped Black P Thin Films for Potential Use in Photovoltaics with Validation from First Principle Calculations: Sayan Sarkar1; Weizhi Zeng1; Michael Free1; 1University of Utah
Black Phosphorus was recently discovered as a 2D material and it exemplified huge prospects for application in photonics. It is a direct band semiconductor with tunable band gap varying from 0.35 eV (bulk) to 2 eV (single layer). But the layer dependent band gap of black phosphorus restricts it to make use of the full spectra of sunlight for absorption. First principle calculations were performed using ‘QuantumWise Atomistix Toolkit’ package for black phosphorus doped with non-metallic dopants of B,S and Se and metallic dopants of Mg and In. It has been found that doping with non-metallic impurities result in a small diminution of the band gap, whereas doping with metallic impurities decrease the band gap drastically. Thus, black phosphorus with the incorporation of some dopants in appropriate amounts can absorb more visible range of the optical spectra, making it ideal for use in photovoltaics.
Energy Efficiency and Sustainability in Steel Production: Lauri Holappa1; 1Aalto University
Iron and steel making plays a significant role in global energy consumption and carbon dioxide emissions. The target of limiting the global warming until 2050 is extremely challenging for this energy-intensive branch of industry. In order to be responsible for its own share in cutting CO2 emissions great advancements must be done. A brief history, present situation and different scenarios are discussed. Possibilities to decrease CO2 emissions in current processes via improved energy efficiency, alternative process routes, energy sources and recycling are examined. On-going and planned efforts and programs of steel producers and institutions, as well as trends of energy generation in the long run are reviewed and evaluated.
Application of Surface Effect on Metallurgical Processes: Kuo-Chih Chou1; 1University of Science & Technology Beijing
The surface effect is one of fundamental topics in physical chemistry that has been studied over decades. However, its effect has been neglected in metallurgy researches and industry applications in the past years. With the progress of science and technology in metallurgy, the consideration of surface effect to the metallurgical processes has been paid more and more attention. In this report, it is shown that, how this factor affects the physicochemical properties of metallurgical processes and how to derive some new and more correct theoretical formulae for its application. Besides, some new technique related to the application of this factor on the experiment has also been developed for both fundamental research and industry applications. It is hoped that these progresses will promote some new developments both in fundamental and industrial applications for metallurgy processes.