Techno-economic assessment of stripping modifications in an ammonia-based post-combustion capture process

Abstract The energy penalty associated with solvent regeneration accounts for the largest part of overall energy consumption in aqueous ammonia (NH3)-based post-combustion capture (PCC) processes. While extensive research focus on the process improvements to reduce the energy burden of solvent regeneration, little attention has been paid to techno-economic assessments that analyse the related energy savings and capital costs. In the present study, we assessed the technical and economic benefits of stripping modifications in an NH3-based PCC process integrated into a coal-fired power station. The stripping configurations included a rich-split process, cold-rich bypass, inter-heating, and combinations of these processes. We used a rigorous, rate-based model in the Aspen Plus® RateSep simulator to determine the technical performance of these new process modifications, while capital investment was estimated with a cost model based on the Aspen Capital Cost Estimator (AACE). All the proposed stripper modifications have technical and economic advantages compared to the reference case. The best configuration was inter-heating integrated with the rich-split process, which reduced reboiler duty by 40.7% and saved 29.2% of annual costs. The sensitivity study suggests that the modified stripping processes can maintain the economic benefits over the wide variations of the important parameters.

[1]  E. Rubin,et al.  A technical and economic assessment of ammonia-based post-combustion CO2 capture at coal-fired power plants , 2011 .

[2]  Kaj Thomsen,et al.  Chilled ammonia process for CO2 capture , 2009 .

[3]  Gary T. Rochelle,et al.  Amine Scrubbing for CO2 Capture , 2009, Science.

[4]  Alfons Kather,et al.  Post-combustion CO2-capture from coal-fired power plants: Preliminary evaluation of an integrated chemical absorption process with piperazine-promoted potassium carbonate , 2008 .

[5]  Moses O. Tadé,et al.  Theoretical and experimental study of NH3 suppression by addition of Me(II) ions (Ni, Cu and Zn) in an ammonia-based CO2 capture process , 2014 .

[6]  Moses O. Tadé,et al.  Rate-based modelling of combined SO2 removal and NH3 recycling integrated with an aqueous NH3-based CO2 capture process , 2015 .

[7]  Kunwoo Han,et al.  Current status and challenges of the ammonia-based CO2 capture technologies toward commercialization , 2013 .

[8]  P. Feron,et al.  A survey of process flow sheet modifications for energy efficient CO2 capture from flue gases using chemical absorption , 2011 .

[9]  Eric Croiset,et al.  Techno-economic study of CO2 capture from an existing coal-fired power plant: MEA scrubbing vs. O2/CO2 recycle combustion , 2003 .

[10]  Alfons Kather,et al.  Evaluating the impact of an ammonia-based post-combustion CO2 capture process on a steam power plant with different cooling water temperatures , 2012 .

[11]  Moses O. Tadé,et al.  Technical and Energy Performance of an Advanced, Aqueous Ammonia-Based CO2 Capture Technology for a 500 MW Coal-Fired Power Station. , 2015, Environmental science & technology.

[12]  Yann Le Moullec,et al.  Process Modifications for Solvent-Based Post Combustion CO2 Capture , 2014 .

[13]  Zhong-yang Luo,et al.  Amine-based absorbents selection for CO2 membrane vacuum regeneration technology by combined absorption–desorption analysis , 2013 .

[14]  Leigh Wardhaugh,et al.  Results from trialling aqueous ammonia-based post-combustion capture in a pilot plant at Munmorah Power Station: Gas purity and solid precipitation in the stripper , 2012 .

[15]  Hai Yu,et al.  Results from trialling aqueous NH3 based post-combustion capture in a pilot plant at Munmorah power station: Absorption , 2011 .

[16]  Gary T. Rochelle,et al.  Cold Rich Bypass to Strippers for CO2 Capture by Concentrated Piperazine , 2014 .

[17]  Leigh Wardhaugh,et al.  Rate-based modelling of CO2 regeneration in ammonia based CO2 capture process , 2014 .

[18]  Shujuan Wang,et al.  Process modeling of an advanced NH₃ abatement and recycling technology in the ammonia-based CO₂ capture process. , 2014, Environmental science & technology.

[19]  Zhong-yang Luo,et al.  Investigation of membrane wetting in different absorbents at elevated temperature for carbon dioxide capture , 2014 .

[20]  Magne Hillestad,et al.  Capital costs and energy considerations of different alternative stripper configurations for post combustion CO2 capture , 2011 .

[21]  L. Øi.  Aspen HYSYS Simulation of CO2 Removal by Amine Absorption from a Gas Based Power Plant , 2007 .