Heat transfer model and scale-up of an entrained-flow solar reactor for the thermal decomposition of methane

✍ Scribed by G. Maag; S. Rodat; G. Flamant; A. Steinfeld

• Publisher: Elsevier Science
• Year: 2010
• Tongue: English
• Weight: 965 KB
• Volume: 35
• Category: Article
• ISSN: 0360-3199
• DOI: 10.1016/j.ijhydene.2010.08.119

✦ Synopsis

The solar thermochemical decomposition of CH 4 is carried out in a solar reactor consisting of a cavity-receiver containing an array of tubular absorbers, through which CH 4 flows and thermally decomposes to H 2 and carbon particles. A reactor model is formulated by coupling radiation/convection/conduction heat transfer and chemical kinetics for a two-phase solidgas reacting flow. Experimental validation is accomplished by comparing measured and simulated absorber temperatures and H 2 concentrations for a 10 kW prototype reactor tested in a solar furnace. The model is applied to optimize the design and simulate the performance of a 10 MW commercial-scale reactor mounted on a solar tower system configuration. Complete conversion is predicted for a maximum CH 4 mass flow rate of 0.70 kg s À1 and a desired outlet temperature of 1870 K, yielding a solar-to-chemical energy conversion efficiency of 42% and a solar-to-thermal energy conversion efficiency of 75%.