DOE OSTI2015
This report documents a preliminary Techno-Economic Assessment (TEA) for processes utilizing Akermin’s second generation biocatalyst delivery system to enhance AKM24, a non- volatile salt solution for CO 2 capture. Biocatalyst enhanced AKM24 offers the potential to reduce the cost of CO 2 capture in flue gas applications due to its improved equilibrium and stoichiometric properties that result in double the absorption capacity relative to previously demonstrated biocatalyst enhanced solvents. The study assumes a new supercritical pulverized coal fired power plant with a net output of 550 MWe after 90% CO 2 capture and uses the June 2011 cost basis (August 2012 update of Bituminous Baseline Study, or BBS). Power plant modeling, capital cost review, and economic calculations were provided by WorleyParsons. Rate-based CO2 capture process modeling and equipment sizing was performed by Akermin using AspenPlus® V8.4, customized to accurately predict thermodynamics, kinetics, and physical properties of the AKM-24 solvent based on available laboratory data. Equipment capital costs were estimated using Aspen Process Economic Analyzer™ which compared well with published baseline cost estimates. Quotes of equipment costs and power consumption for vacuum blower and CO 2 compression equipment were also provided by Man Diesel & Turbo. Three process scenarios were examined for Akermin biocatalyst enhanced solvent systems including: Case-1A: an absorption-desorption system operated with a reboiler pressure of 0.16 bara (60°C); Case-2A: an absorption-desorption system with moderate vacuum assisted regeneration at 0.40 bara (80°C); and finally, Case-2B: a conventional absorption-desorption system with near atmospheric pressure regeneration at 1.07 bara (105°C). The estimated increases in cost of electricity (ICOE) for these cases were $58.1/MWh, $47.3/MWh and $46.4/MWh, respectively. Case 2B had the best results for this analysis achieving an estimated 30% reduction in ICOE relative to the NETL Case 12 (v2) baseline of $66.3/MWh ICOE. Likewise, Case-2B achieved capture costs of $53.0/tCO2 and 65.7/tCO 2 avoided, which equates to 20.2% and 31.4% savings relative to the Case 12 baseline ($66.4/tCO 2 and $95.9/tCO 2 avoided). While Case 2A and 2B have similar results, Case 2A requires further development. Focus on Case 2B is recommended for this project because its cost performance is closest to the DOE goals, and has it has the best potential to achieve a successful demonstration at the next scale.