Integration of indirect mechanism autothermal reforming process with chilled methanol scrubbing solution for syngas purification: Power generation exploiting blue hydrogen as fuel

Abstract

This paper focuses on the design of blue hydrogen production through indirect mechanism autothermal reforming of natural gas applied to a combined cycle power plant with 420 MW total gross power generation. Excluding the pre-combustion CO₂ capture, a natural gas combined cycle power plant has been modeled as a reference case. Despite the traditional configuration, all the required heat in stripping towers is generated from the ATR process. Moreover, a double-pressure organic Rankine cycle is coupled with the reforming process through heat integration. Approximately 10.36 kg/s H₂ with 96.137 mol% purity, 67.41 MJ/kg Lower Heating Value, and 78.42% Cold Gas Efficiency is produced by 93.87% CO₂ capture ratio in the Rectisol process with the specific heating consumption of ∼1.59 MJ/kg CO₂. The final plant demonstrates that the total net power generation has improved from 353.24 MW to 382.38 MW, and net efficiency has been ameliorated by 4.17%. Additionally, the energy penalty is remarkably reduced by 7.19% compared to a plant without an organic Rankine cycle. Eventually, the specific CO₂ emission decreased from 31.98 to 29.55 gCO₂/kWh, as well as the annual emission of CO₂ that has declined significantly from 1231.66 to 98.97 ktons/year.