Carbon Capture Costs: FEED & pre-FEED Cost Reports

Prairie State Generating Company is conducting a FEED study for a carbon capture facility on its 816 MWe Unit #2 in Illinois, using Mitsubishi Heavy Industries’ KM CDR Process™ with KS-21™ solvent. Designed to treat all flue gas from the unit, it would be the world’s largest post-combustion capture plant, compressing CO₂ for off-site sequestration. The project will leverage engineering support from Kiewit, Sargent & Lundy, and MHI.

Analysis sets the design and cost-estimating basis for evaluating pulp and board mills with and without CCS. Two base cases are considered: a market pulp mill and an integrated pulp and board mill. Six CCS cases are evaluated, capturing CO₂ from the recovery boiler, multi-fuel boiler, lime kiln, or their combinations. The mills are assumed to be energy independent, with black liquor and bark burned to produce steam and electricity, and excess electricity exported to the grid. The CO₂ capture system uses post-combustion MEA technology with a 90% capture rate, and if on-site electricity is insufficient, an auxiliary boiler firing forest residues will supply the additional energy. Capture of CO2 in both Kraft Boiler & Lime Kiln

Studied the replacement of the SMR units with auto-thermal reforming (ATR) technology. ATRs produce a high concentration CO₂ stream, instead of low concentration combustion flue gases, that is more efficient to capture for sequestration. H₂ production from the unit may also be oversized to provide H₂ as a fuel source for the ATR if target overall CO₂ recovery of the facility is not achieved with the replacement of the SMR alone. The facility capacity is based on the total H₂ production requirements of the existing Plant 01 and Plant 09 ammonia synthesis units. 3 | P a g e Public – Approved for external distribution The scope for the study involves the SMR unit replacement with an integrated ATR and downstream syngas purification including CO₂ capture. The project scope also includes an Air Separation Unit (ASU) to supply oxygen to the ATR unit.