Carbon Capture Costs: FEED & pre-FEED Cost Reports

CO₂ capture from the SMR flue gas stacks located in Plant 01 and Plant 09 of the facility. Combined flue gases from each of the two sources would be collected and transported by ducts to the carbon capture facility. The design of the capture facility is 2,100 – 2,200 tpd of CO₂, including the CO₂ captured from the SMRs and additional flue gas generated from the steam boiler supplying the CCS unit. The CCS unit is to be designed for a minimum 30% plant turndown, this is to ensure the operation of CCS unit when flue gas from Plant 01 is the only feed to the CCS unit. For the purposes of the study the carbon capture facility design, including flue gas pretreatment and downstream CO₂ compression and dehydration, is provided by licensor. Hatch designed the flue gas transportation from the stacks to the Carbon Capture and Sequestration (CCS) unit battery limit, flue gas pressure boosting and Balance of Plant (BOP) which includes all the utility and offsite systems

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.

ION Clean Energy, with Nebraska Public Power District, is conducting a FEED study to retrofit a CO₂ capture system on Unit 2 of the 700 MWe Gerald Gentleman Station in Nebraska. Using ION’s low-aqueous ICE-21 solvent, proven in prior DOE-funded projects to reduce energy use, solvent degradation, and emissions, the design will feature two parallel 350 MWe capture units. The project aims to decarbonize most of Unit 2 while maintaining maximum operational flexibility for the plant.