Operation post-processors

Total moles of all sulfur-bearing components present in the system are required by EQPS from data on tabular files output by EQ6 or input from the user. The input modules allow expansion to integrate with other codes as necessary. The choice of a post-processor mode of operation for EQPS, rather than integration into the EQ6 code as for the oxygen and hydrogen isotopic calculations of Bowers and Taylor (4), was made primarily because of the complexities of sulfur chemistry discussed above. By using the post-processor approach the computationally intensive EQ6 code is only run once for each chemical reaction path, while the simpler and much faster EQPS code can be run multiple times to examine the effects of various isotopic reaction constraints. 

The semantic processing of the post-processor is determined by the directives of the operator, by the actual interpretation and, in case of errors by the error handling. 

The post-processor expects at least the following directives from the operator ... 

We describe the design, operation and operational results of the durability system, including the operating conditions for the system, fuel processor subsystem operation over 1000 hours, post-mortem characterization of the catalysts in the fuel processor, and single cell operation. 

Figure 4 shows operation of the fuel processor subsystem on iso-octane for 11 days, after which the fuel was switched to a simulated gasoline of 74% iso-octane, 20% xylene, 5% methylcyclohexane and 1% 1-pentene. After only two days of operation on this simulated gasoline, the pressure drop between the ATR and HTS increased due to carbon formation. Post characterization of the carbon formed showed that a high concentration of solidified hydrocarbons were present in the carbon (30% by weight). To prevent carbon formation between these reactor sections, the HTS water injection was moved from the inlet to the HTS to the outlet of the steam reformer section. 

Current results indicate operational issues for the fuel processor subsystem to meet the DOE durability target of 5000 hours due to carbon formation and catalyst surface area. Upon post-analysis of the fuel processor, carbon formation was observed regardless... 

Yoon, S, Bae, J. A diesel fuel processor for stable operation of solid oxide fuel cell system I. Introduction to post-reforming for the diesel fuel processor. Catal. Today 2010 156 49-57. 

---