Membrane reforming in converting natural gas to hydrogen (part one)

• Published in: International journal of hydrogen energy Vol. 33; no. 14; pp. 3700 - 3709
• Main Authors: Barba, D., Giacobbe, F., De Cesaris, A., Farace, A., Iaquaniello, G., Pipino, A.
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01.07.2008; Elsevier
• Subjects: Alternative fuels. Production and utilization; Applied sciences; Energy; Exact sciences and technology; Fuels; Gas turbine; Hybrid system; Hydrogen; Membrane; Natural gas; Reforming; Membrane; Reforming; Gas turbine; Natural gas; Hybrid system; Methane; Energy consumption; Sensitivity analysis; Palladium; Membrane separation; Membrane reactor; Reforming,Membrane,Gas turbine,Natural gas,Hybrid system; Comparative study; Hydrogen production
• ISSN: 0360-3199; 1879-3487
• DOI: 10.1016/j.ijhydene.2008.04.038

Membrane reforming reactors (MRR) could play a key role in converting natural gas into hydrogen. The major advantage of MRR architecture is the possibility to shift the chemical equilibrium toward the right-hand side of the reaction, improving hydrogen production and allowing, the same time high methane conversion at relatively low temperatures such as 650 °C. Such a low operating temperature makes it possible to locate the MRR downstream of a gas turbine, achieving an efficient hybrid system (power+hydrogen) with a significant reduction in energy consumption (around 10%). This paper discusses the whole innovative architecture where conventional tubular reforming is integrated with hydrogen permeable palladium membrane separators. The fundamental concepts are analyzed and integrated into a process scheme; the structural effects of variables design such as reactor temperature outlet, S/C ratio and recycle ratio throughout pinch and sensitivity analysis are described, and a comparison of the process economics with conventional hydrogen technology is presented at the end of the second part of this paper. The production of highly reliable, defect-free and reproducible, Pd-alloy membranes for selective hydrogen separation is a key issue in the proposed hybrid architecture.