Simulation of Solar Thermo-Chemical Hydrogen Production Techniques

This paper presents material and energy process-step models of hydrogen production via concentrated solar energy using Aspen Plus^®. The paper provides a thorough comparison of solar cracking and solar reforming of methane processes against conventional steam methane reforming. The material and energy balances show that solar cracking is the most environmentally friendly hydrogen production technique. Some of the primary advantages of solar cracking include (1) elimination of CO₂ emission, (2) elimination of costs associated with CO₂ sequestration, transportation, and storage, and (3) generation of two commercially viable products, namely carbon black and hydrogen which can be used both as a fuel and a commodity. Considering the hydrogen shortage for different hydrogenation and fuel upgrading processes that the petrochemical industry is facing today, hydrogen production from solar cracking may offer an alternative solution. Therefore, it is important to find less energy intensive and more environmentally friendly hydrogen production techniques to meet the demand of industry. The results show that solar cracking is a more environmentally friendly and commercially competitive process compared to solar reforming and steam reforming considering that it produces virtually no carbon dioxide, but produces the commercially viable carbon black as a by-product.