Validation of a water-gas shift reactor model based on a commercial FeCr catalyst for pre-combustion CO2 capture in an IGCC power plant

In the Nuon/Vattenfall CO2 Catch-up project, a pre-combustion CO2 capture pilot plant was built and operated at the Buggenum IGCC power plant, the Netherlands. The pilot consist of syngas conditioning, sweet water-gas shift, condensate recovery, bulk CO2 separation by physical absorption using dimethylether of poly-ethylene-glycol (DEPEG) as solvent, solvent regeneration and CO2 compression. The project aimed at verifying the technology performance and at generating knowledge in the form of validated models and operational experience. This paper describes the construction and validation of the model for the WGS reactors. A one-dimensional heterogeneous reactor model was developed. The intrinsic kinetics was measured in the lab at 20 bar pressure, 350-450 degrees C and in the presence of 5-20 ppm of H2S. The engineering reactor model is successfully validated against a set of 20 steady-state pilot plant operational periods varying in inlet temperature, syngas composition and throughput. A good fit of the pilot plant data was obtained by moderately tuning the relative catalyst activity in the model to the state of the catalyst in the pilot. This indicates that the lab-scale catalyst ageing procedure effectively mimics the initial catalyst deactivation observed in the pilot plant. (C) 2014 Elsevier Ltd. All rights reserved.