Thermodynamic and kinetic analysis of an integrated solar thermochemical energy storage system for dry-reforming of methane

• Published in: Energy (Oxford) Vol. 164; pp. 937 - 950
• Main Authors: Xie, Tao, Xu, Kai-Di, He, Ya-Ling, Wang, Kun, Yang, Bo-Lun
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01.12.2018; Elsevier BV
• Subjects: Absorptivity; Alternative energy; Carbon dioxide; Chemical reactions; Conversion; Energy storage; Factor analysis; Flow rates; Flow velocity; Heat transfer; Integrated thermodynamic analysis; Kinetics; Mass transfer; Mathematical models; Methane; Organic chemistry; Parameter optimization; Parameters; Plug flow; Plug-flow kinetic model; Reactors; Reforming; Solar energy; Solar power; Solar thermochemical energy storage; Storage; Temperature; Thermodynamic models; Thermodynamics; Transient operation; Transportation; Solar thermochemical energy storage; Integrated thermodynamic analysis; Parameter optimization; Plug-flow kinetic model
• ISSN: 0360-5442; 1873-6785
• DOI: 10.1016/j.energy.2018.08.209

Thermodynamic analysis for an integrated solar thermochemical energy storage system was conducted to examine its energy and chemical conversion performances. Detailed mathematical description for the transportation process of radiation energy was given to obtain the input solar power to the solar receiver/reactor. Plug-flow model was used to determine the species concentrations and temperature distributions of the solar reactor combined with kinetic models. Then concentrations of species and temperature at outlet of solar reactor were used in the overall thermodynamic model to investigate the effects of key parameters on thermal performance of the system. The results shown that each of the key parameters (initial molar flow rate, diameter and length of reactor, initial molar ratio of CH4/CO2, and absorption coefficient) produced both of positive and negative influences on energy and chemical conversion performances. In order to fully utilize the input energy and feed gas, mass transfer/heat transfer and chemical reaction rate should match with each other. So in both single factor analysis and transient operation condition analysis, the operation parameters were optimized which significantly improved the cycle work efficiency ηcycle (from 17.72% to 34.04% on 12:00 of Summer Solstice, and from 19.53% to 33.37% on 12:00 of Winter Solstice). •Thermodynamic & kinetic analysis was conducted for thermochemical energy system.•Mathematical model for solar transportation & chemical reaction were established.•Effects of key parameters on system performances were investigated.•Operation parameters were optimized to increase the energy conversion efficiency.