Economical analysis of hydrogen production by autothermal reforming of hydrocarbons in a novel membrane reformer. Paper no. IGEC-1-078

The economic evaluation of hydrogen production by steam reforming of hydrocarbons in an earlier suggested novel Autothermal Circulating Fluidized Bed Membrane Reformer (ACFBMR) (Chen and Elnashaie, Chem. Eng. Sci., 2004; Chen and Elnashaie, AIChE, 2004) is performed. Heptane is used as a model component for liquid/heavy hydrocarbons. The specifications and costs of the main units/equipments are determined based on the process calculation and available market data. Using statistical correlations and cost factors, the total capital investment is determined. The economical analysis shows that the hydrogen production cost generally decreases with the increase of plant size. For a small pilot plant with a capacity of 100 kg- H2/day, the hydrogen cost from industrial steam methane reforming is about $9.10/kg-H2, while in this novel autothermal reformer-regenerator system the hydrogen costs are $2.054/kg-H2 for methane feed and $2.224/kg-H2 for heptane feed. The cost reductions are 77.43% and 75.56%, respectively. For a typical industrial large plant of 100,000 Nm3- H2/h (equivalent to 214,286kg-H2/day) (Scholz, Gas Separation and Purification, 7(3), p131-139, 1993), the reported industrial hydrogen production cost by steam methane reforming is about $0.739-0.966/kg- H2, while using this autothermal process, the hydrogen production costs are $0.664/kg-H2 from heptane and $0.501/kg-H2 from methane, respectively. The cost reductions are 10.15%- 31.26% and 32.21%-48.14%, respectively. The comparison of hydrogen production costs shows that the hydrogen production cost using this novel autothermal reformer-regenerator process is lower than the reported cost from the most economical steam methane reforming in fixed-bed reformers. Thus this ACFBMR can be a more efficient and more economical pure hydrogen producer. (author)