Process design for H2S Enrichment in physical solvent DMEPEG

Acid gas removal from syngas is an important process upstream of CO2 capture in a pre-combustion IGCC power plant. Enrichment of previously absorbed H2S in DMEPEG solvent (by stripping out the CO2 co-absorbed with H2S) is described in this publication. The unique capability of ProTreat software to conduct rate based mass transfer simulation is described and applied for H2S Enrichment simulation. Non-ionic liquid property model and its implementation in ProTreat software is described. Solubility of CO2 and H2S in DMEPEG solvent is described. Process condition for H2S Enrichment is justified in terms of its integration within the overall IGCC power plant. Sensitivity study is conducted for various important process parameters. systematic development and optimizations of H2S Enrichment process is described considering optimization of techno-economic performance parameters. Interaction and integration of H2S Enrichment with H2S absorption and H2S Stripper is analyzed. Performance and mass balance across H2S Enrichment is described. Limitations of this process design are also described. Various options are suggested for tower internals resulting in similar performance. This kind of detailed process design is necessary for accurate detailed CAPEX assessment (by bottom-up approach) and techno-economic assessment.