Development of a high-efficiency Hydrogen generator for Fuel cells for Distributed Power Generation

Development of a high-efficiency Hydrogen generator for Fuel cells for Distributed Power Generation

Authors: K. Durai-Swamy, Ph.D., Joshua Mauzey, Lei Wang, Ph.D., & Diane Aagesen, Intelligent Energy, Gregory Smith, Ph.D.,  Yi Liu, Ph.D., & Mingheng Li, Ph.D., California Polytechnic University, Pomona, CA

Correspondence: durai.swamy@intelligent-energy.com

Conventional hydrogen generation by steam methane reforming (SMR), employing a high temperature reformer (~800C), a water gas shift reactor (~300C) and  multiple pressure swing adsorbers, operates at an efficiency of around 65 to 67% based on lower heating value (LHV) of feed and product. This conventional SMR system is not very easy to scale down cost-effectively for supplying 35 to 150 slpm H₂ (to produce 3 to 13 kW electricity).  Intelligent Energy has developed an adsorption enhanced reformer (AER) for the H₂ generation for use in conjunction with fuel cells in the small sizes (3 to 13 kW). This AER has an efficiency of around 80% on LHV basis and operates at lower temperature (~500C) than the SMR.

The AER employs a carbon dioxide (CO₂) capturing material with the reforming catalyst which removes the CO₂ from the products to effect the reactions to go forward such that H₂is produced in one step with little CO and CO₂ impurities. H₂ content in the product is over 98%, the balance being unconverted methane. This paper presents the results from an AER unit with four beds and overall process simulation. The AER unit has been operated with ethanol, natural gas and LPG as feeds. This project is partially supported by US. DOE (contract # DE-FC36-07GO17013).References:

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