Effect of hydrocarbon fractions, N2 and CO2 in feed gas on hydrogen production using sorption enhanced steam reforming: Thermodynamic analysis. (24th August 2017)

• Record Type: Journal Article
• Authors: S G Adiya, Zainab Ibrahim; Dupont, Valerie; Mahmud, Tariq
• Is Part Of: International journal of hydrogen energy. Volume 42:Number 34(2017)
• Page Start: 21704
• Page End: 21718
• Publication Date: 2017-08-24
• Subjects: Shale gas -- Steam reforming -- Sorption enhancement -- C1–C3 species -- N2 -- CO2; Hydrogen as fuel -- Periodicals; Hydrogène (Combustible) -- Périodiques; Hydrogen as fuel; Periodicals; 665.81
• DOI: 10.1016/j.ijhydene.2017.06.169
• Languages: English
• ISSNs: 0360-3199

Abstract

Abstract: H2 yield and purity from sorption enhanced steam reforming (SE-SR) are determined by temperature, S:C ratio in use, and feed gas composition in hydrocarbons, N2 and CO2 . Gases with high hydrocarbons composition had the highest H2 yield and purity. The magnitude of sorption enhancement effects compared to conventional steam reforming (C-SR), i.e. increases in H2 yield and purity, and drop in CH4 yield were remarkably insensitive to alkane (C1C3) and CO2 content (0.1–10 vol%), with only N2 content (0.4–70 vol%) having a minor effect. Although the presence of inert (N2 ) decreases the partial pressure of the reactants which is beneficial in steam reforming, high inert contents increase the energetic cost of operating the reforming plants. The aim of the study is to investigate and demonstrate the effect of actual shale gas composition in the SE-SR process, with varied hydrocarbon fractions, CO2 and N2 in the feedstock. Highlights: Feedstock for steam reforming was shale gas, of four different compositions. Sorption enhancement (SE) measured by comparison with conventional SR (C-SR). Nature of the alkane gases and CO2 (0–10%) in the feedstock do not affect SE. Highest SE for feed gas with little N2 dilution, no SE above 1050 K at 1 atm. Inhibition of methanation larger for larger N2 content at temperatures below 750 K.