报告题目：A Multiscale Model for Nickel-based Oxygen Carriers in Chemical-looping Combustion

报告人：Prof. Luis Ricardez-Sandoval

Department of Chemical Engineering,University of Waterloo，Canada

报告地点：能动(原热能系)系馆第一会议室

主办单位：能源与动力工程系 清华大学-滑铁卢大学微纳米能源环境联合研究中心

报告时间：2018年7月30日上午10:00-11:00

Abstract:

Computer modeling is a powerful tool that aids the design and manufacture of nanomaterials. While atomic-scale modeling can provide information on the characteristics of the cluster of atoms or molecules, it is often difficult to simulate the model in time or length scales that are adequate to describe the macroscopic properties of relevant nanomaterials. Therefore, developing a multiscale model that is capable of describing both atomistic and macroscopic phenomena of the nanomaterial can advance the understanding on the effect of atomic structures and properties. Chemical looping combustion (CLC) is an energy-efficient scheme to realize fossil fuel conversion with inherent CO2 capture. Oxygen carrier materials (OC) are used in this process to avoid direct contact between air and fossil fuels, thus eliminating the production of gaseous mixtures (mainly N2 and CO2 in traditional combustion processes). A highly concentrated CO2 stream is generated as a gaseous combustion product to facilitate the CO2 disposal without the need of energy-intensive gas-gas separation processes. Theoretical studies that provide insight on phenomena taking place inside the OC particle are limited. Moreover, studies that couple atomistic and microscopic events inside (and in the vicinity of) the OC particle are currently not available.

In this talk, we will present the efforts conducted in our research group towards the development of a new multiscale modelling framework for nickel-based oxygen carrier (OC) materials used in the chemical looping combustion of gaseous fuels (e.g. syngas). Density functional theory (DFT) analysis is used as a computational tool that can provide insight at the atomistic scales in OC materials, e.g. elementary reaction path mechanisms, oxygen vacancy and neighboring effects, stable model structures and energetic properties of the targeted nickel-based OC particles (e.g. nickel-oxide). Insights from the DFT analysis are key to build highly predictive surface models based on mean field approximations (MFA) and kinetic Monte Carlo (kMC) simulations, which can explicitly take into account surface neighboring effects. Predictions coming from these models will be instrumental to elucidate the microscopic properties and performance of the OC materials. Moreover, MFA or kMC models can be coupled with continuum mass transport equations to couple the surface-gas diffusion effects inside (and in the vicinity of) the OC particles. As it will be shown in this presentation, outcomes from this multiscale modelling approach can lead the design of attractive oxygen carrier materials for the CLC process by providing new insights on the underlying mechanisms affecting the reduction process in OC particles and fossil fuel conversion.

Brief biography:

Dr. Luis Ricardez-Sandoval is a Canada Research Chair in Multiscale Modelling and Process Systems (CRC-Tier II) and an Associate Professor in the Department of Chemical Engineering at the University of Waterloo. He received his B.Sc. from Technological Institute of Orizaba (Mexico) in 1997, his M.Sc. from Technological Institute of Celaya (Mexico) in 2000, and his Ph.D. degree from the University of Waterloo in 2008. During his academic career, Dr. Ricardez-Sandoval has published more than 80 journal articles, 25 full-length peer-reviewed conference papers, 3 book chapters and 1 monograph. His current research interests include multiscale modelling and control of thin film deposition and heterogeneous catalytic systems under uncertainty; optimal design and operations management of systems under uncertainty; design and operation of CO2 capture and advanced power generation technologies with near-zero emissions and process scheduling of industrial-scale systems. Dr. Ricardez-Sandoval’s research has been supported by a network of collaborators from the federal government, private companies and the government of Ontario. Dr. Ricardez-Sandoval has received multiple awards including the 2015 Ontario Early Researchers Award (ERA) and the 2015 Engineering Research Excellence Award. Dr. Ricardez-Sandoval is an Associate Editor of the Canadian Journal of Chemical Engineering (CJChE) and is a member of the Systems and Control division of the Chemical Institute of Canada (CIC) and the American Institute of Chemical Engineers (AIChE).