Figure 2. Catalyst packing picture: Reforming catalysts are packed to a reactor for laboratory VTT tests to test the activity of the catalysts and to study the operation window
Figure 3. Catalyst testing picture: The reforming catalysts are tested in laboratory scale with model gases to find operation window and for the basis of the design of the reformer for STAGE-SOFC system in VTT labs
Characterization of the STAGE-SOFC system
In order to reinforce environmentally friendly technologies for small-scale CHP units in the range of 5 to 50 kW, the development of an SOFC based system with high electrical efficiency of up to 45% and an overall efficiency of approximately 85% is intended in the framework of the STAGE-SOFC project.
The idea behind the STAGE-SOFC concept, which is presented in Figure 1, is the serial connection of an exothermal CPOX stage with one or multiple endothermic steam reforming stages. The system will combine the benefits of a simple, robust CPOX layout with high efficiencies achievable using a steam reforming process. This concept has the following advantages:
- No process water requirement (only natural gas and air as input)
- Fuel supply for stage 2 by reforming of natural gas with anode-off gas from stage 1
èNo flow control in hot gases required
èNo recirculation blower required
- Small heat exchangers for cathode air preheating (heat up of stage 2 by hot cathode-off air from stage 1)
- Dynamic operation down to 10% of maximum system load
- High exhaust gas temperature for flexible heat usage
- Electrical efficiency of up to 45% at maximum system load
Figure 4. STAGE-SOFC system layout with main components
A design of STAGE-SOFC PT1 and a testing set up of PT1 are presented in Figures 5 and 6, respectively.
Figure 5. STAGE-SOFC PT1 system
Figure 6. Testing of PT1
Sunfire team in front of the PT1 is shown in Figures 7-8.
Figure 7. Commisioning and safety checks
Figure 8. sunfire team in front of prototype