Inyong Kang

The Tests of 1 kWe Diesel Reformer and Solid Oxide Fuel Cell System

The high temperatures required to operate solid oxide fuel cells (SOFCs) allow for internal reforming of hydrocarbon fuels over a Ni-based anode. With their capability of being fuel flexible, SOFCs have operated under a wide range of fuels including diesel as examined in this study. But in order to reduce high possibilities of deposit formation in diesel internal reforming, additional external reforming technology was used for our system. The final goal of this research is to develop 1 kWe diesel-powered SOFC systems for residential power generation. Before constructing a complete 1 kWe SOFC system, a series of durability experiments were conducted on individual components of the system including the fuel reformer and stack. After testing the full-scale 1 kWe diesel reformer, deposit formation was visible within the catalyst and on the surface of the reactor head, which seriously degraded the performance. With several individual components tested, the construction of one-box type 1 kWe SOFC system is in progress. In a preliminary six-cell stack test using sulfur-free synthetic diesel, the system initially showed an output power of ∼110 kWe at a 0.8 V average cell potential. However, there was a significant drop off in output power after a few hours of operation, which was likely caused by severe deposit formation on the SOFC stack. Light hydrocarbons such as ethylene and/or “less reformed” heavier hydrocarbons caused by gas reactions under the incomplete fuel mixing upstream of the catalyst were likely responsible for the deposit formation.

Effect of the Molar H 2 O/ and the Molar O 2/C Ratio on Long-Term Performance of Diesel Autothermal Reformer for Solid Oxide Fuel Cell

Solid oxide fuel cell(SOFC) has high fuel flexibility due to its high operating temperatures. Hydrocarbonaceous fuels such as diesel has several advantages such as high energy density and established infrastructure for fuel cell applications. However diesel reforming has technical problems like coke formation in a reactor, which results in catastrophic failure of whole system. Performance degradation of diesel autothermal reforming (ATR) leads to increase of undesirable hydrocarbons at reformed gases and subsequently degrades SOFC performance. In this study, we investigate the degradation of SOFC performance(OCV, open circuit voltage) under hydrocarbon(n-Butane) feeds and characteristics of diesel performing under various ratios of reactants( molar ratios) for improvement of SOFC performance. Especially we achieved relatively high performance of diesel ATR under

kW-class Diesel Autothermal Reformer with Microchannel Catalyst for Solid Oxide Fuel Cell System

H_2O/C

Study on Autothermal Reforming of Diesel

Abstract Solid oxide fuel cell(SOFC) has a higher fuel flexibility than low temperature fuel cells, such as polymer electrolyte fuel cell(PEMFC) and phosphoric acid fuel cell(PAFC). SOFCs also use CO and CH 4 as a fuel, because SOFCs are hot enough to allow the CH 4 steam reformation(SR) reaction and water-gas shift(WGS) reaction occur within the SOFC stack itself. Diesel is a good candidate for SOFC system fuel because diesel reformate gas include a higher degree of CO and CH 4 concentration than other hydrocarbon(methane, butane, etc.) reformate gas. Selection of catalyst for autothermalr reforming of diesel was performed in this paper, and characteristics of reforming performance between packed-bed and microchannel catalyst are compared for SOFC system. The mesh-typed microchannel catalyst also investigated for diesel ATR operation for 1kW-class SOFC system. 1kW-class diesel microchannel ATR was continuously operated about 30 hours and its reforming efficiency was achieved nearly 55%.

Study on Reaction Characteristics and Catalysts to Reform Diesel for Production of Hydrogen

Diesel is one of the best hydrogen storage systems, which has very high volumetric density [kg H2 /m3 ] (>100) and gravimetric density [%H2 ] (>15). Several catalysts were selected for diesel reforming. 3 catalysts (Pt on gadolinium doped ceria, Rh and Ru on the same support, Patent for catalyst formulation of Argonne National Laboratory in U.S.A) and 2 commercial catalysts (FCR-HC14 and FCR-HC35, Sud-Chemie, Inc.) were used to reform diesel. Pt catalyst showed the best performance. Effects of operating conditions such as temperature, O2 /C and H2 O/C on ATR (autothermal reforming) were investigated. In addition, we studied on reaction characteristics for better understanding about ATR reaction by analyzing concentrations of products and temperature profiles along catalyst bed. We found key issues such as fuel delivery and heat transfer between front exothermic part and rear endothermic part of catalyst bed.Copyright

Performance comparison of autothermal reforming for liquid hydrocarbons, gasoline and diesel for fuel cell applications

Diesel is one of the best hydrogen systems, which has very high volumetric density

Autothermal reforming study of diesel for fuel cell application

[kg\;H_2/m^3]\;(>100)\;and\;gravimetric\;density[\%\;H_2]\;(>\;15)

Effects of ethylene on carbon formation in diesel autothermal reforming

Several catalysts were selected for diesel reforming. 3 catalysts of our group (NECS-1, NECS-2, NECS-3) and 2 commercial catalysts (Sud-Chemie, Inc, FCR-HCl4, FCR-HC35) were used to reform diesel. NECS-1 showed the best performance to reform diesel. In addition to these results, we studied on reaction characteristics for better understanding about auto thermal reforming of diesel by investigating product gas concentrations and temperature Profiles along the catalyst bed. We found technological issues such as fuel delivery and thermal configuration between front exothermic part and rear endothermic part.